AP Environmental Science Day 3 Overview

hey everyone welcome back it is day three ap daily live ap environmental science thanks for being here for the third day in this series i'm going to go ahead and start my screen so before we get started let me reintroduce myself my name is lisa bagley i teach in texas right outside of dallas mesquite isd go wranglers what are we going to learn today well funny you should ask on this earth day eve in ap daily live video 3 we're going to answer questions and provide clarification of concepts from video 2. we're going to conduct a brief overview of content for unit 4 earth systems and resources we're going to practice connecting our free response questions to answers uh free response question answers to the science practices in order to maximize score potential and we're going to wrap up with questions and a link to some live practice just a reminder on what these videos are for and how to use them ap daily live videos are designed to help you understand how to demonstrate your environmental science content knowledge via the essential science practices the college board expects you to know these are not specifically content review videos however the ap daily content videos that are presented in the units discussed for each of the review videos will be referenced during the presentations i want to clarify that just a little bit um for this particular unit and whatever unit we're talking about this happens to be unit four um if the content pertains to unit four i will not reference that video because those are those videos because we have just gone over that content but if the content comes from outside of the unit four videos then those videos will be referenced during the free response uh question modeling portion of the videos i'll point out common pitfalls that students often make when answering these exam questions and offer suggestions on how to avoid these and to maximize your scoring potential and as always the videos are best used in conjunction with individual review on your own time because of course you know best what you need to work on so first let's jump into questions and clarifications from this should say video video uh two this is going to be a video two clarifications so um again i want to thank everybody y'all are really amazing when it comes to giving feedback and suggestions like it's really really good and i want to give a shout out to everybody about that so the the first one i want to hit is can you go over the format of the exam please well thanks for asking we did that um back in video one of the series the exam specifics were discussed in detail so if you still need to figure out what is going on with the specifics of the exam please take a look at video one the first part of that video does talk about that in detail all right several of you were questioning about if i'm a paper test taker how do i organize my free response questions and what if i need to skip and come back to a section so shout out to preston h from utah for asking that question the organization of free response questions on the paper exam is best done in the same order as the questions so um for answer for example if you know you're answering question uh prompt a putting prompt at you know putting the a in parentheses and then answering it that's the easiest way for a reader to figure out what you're talking about where your points are however that said if you need to skip a section and come back you can either leave some blank space and then come back and write there or you can put the skipped section at the end of your answer to that question but make sure you label it it just makes it easier for us to find your points when we're scoring it math math and more math lots of questions about the math so can my math setup be different than the model and still earn points the answer to that is yes it can the math setup can be different and you can still earn points but the bottom line is that your ap reader must clearly be able to see both your units in the setup and the answer and they must be able to logically follow your math steps to arrive at the answer that you've given there if the math is not like if the math is not followable is that even a word if the math is not followable or you don't have what's required which are units in setup and answer then it would not be pointable several of you asked for significant figures as for sig figs there's no hard and fast rule usually two sig figs is plenty on the apes exam and no you do not have to put your answer into scientific notation several of you guys were like hey i have this in non-scientific notation because scientific notation freaks me out cool it doesn't matter as long as it's the same answer as we would get with scientific notation no problem whatsoever uh it just makes it easier for us to look at sometimes but still pointable several people asked about how do i show my map in the digital app so here's the deal with the digital app there's you've got the practice app there so one of the things with the practice app is that they have practice problems that are loaded there and i'm going to really highly suggest like really suggest that you guys practice in your digital app um putting those math equations in there just to see how you do it there's nothing in apes that can't be done on a keyboard in terms of math and of course you know you're going to be able to type your units or whatever so you've got a mixture of you know keyboard commands like the divide sign or the multiplication the star for multiplication should be able to do all of that but practice practice so you're not going in cold all right so if we answer a free response question correctly but the answer isn't on the rubric do we still get a point um good question and the answer to that is it depends um if you're so if you if you have an off rubric answer uh we'll evaluate it uh during the reading and if it's deemed to be a legitimate answer to the prompt right then it's up to the question leader as to whether or not that will be pointed the decisions are actually made on an individual basis however if lots of examinations have a similar answer then that answer might actually be added to the scoring rubric as a modification um so generally speaking the rubric is set um but there there is some wiggle room if there is an frq answer that fits but it hasn't been identified on the rubric that's fairly rare however is there anything we should actually memorize for this exam this exam is not um really high on memorization i would suggest knowing some basic stats like how many people are on earth and what's the approximate population of the united states but in general this exam is really about the connection of concepts and phenomena rather than memorized facts and figures the questions that you're modeling are asking for solutions to environmental problems but i don't know these solutions where are they well the solutions to environmental problems are kind of scattered throughout the content of the course and that's according to unit so just a caveat units one through four don't have a lot of solutions to environmental problems and that is because of the nature of units one through four they're mostly focused on basic environmental science concepts right so so um the make a claim you'll see in a lot of these models that make a claim comes from other units in these in these first few units because there's not a lot of making a claim you're going to do with with certain ecology concepts or or systems concepts you'll we are going to see this pick up a lot in unit 5 and continue on through the rest of the videos throughout the rest of the course and unit 5 is going to be covered tomorrow in our live session on april 22nd so you're going to see how that unit how the content of that unit lends itself to environmental solutions and i'll point that out specifically all right so what would be an example of a social solution to an environmental problem i i had mentioned that you need to make sure that you're actually answering the type of solution that they're asking for well good question you could have an education or a public information campaign um citizen science initiatives like what lois gibbs did with love canal or aaron brockovich in hinckley california with you know toxic waste dumping or margie richard in norco louisiana so if you don't know who these people are those are great case studies you might want to look them up hey miss bagley can you model how a make a claim answer would look if you were to write it um thank you for asking in these videos i've just kind of been giving you what the rubric prompt will look like but i haven't modeled exactly what a student response might look like so we're going to talk actually we're going to do several make a claims tonight so here's a modified one you know that i took from today's practice based on the diagram which you'll see later make a claim using evidence that a regulating ecosystem service has been devalued as a result of human activities okay so you've got to make a claim you've got to use evidence from the diagram and you've got to specifically mention regulating ecosystem services three things you gotta hit here the diagram shows a forest that has been clear-cut near stream two intact forests provide humans with many regulating surfaces like erosion control and carbon sequestration so clear cutting a forest devalues the ecosystem services they provide i'm telling you that i saw in the diagram that there is a forest that's been clear cut right and i know that intact forests provide ecosystem services and i gave an example of that and i'm telling how the clear cutting would devalue those ecosystem services that hits all three of those okay so that's how it would look like in narrative format rather than rubric format all right hey what's an eco what's an indicator species again all right an indicator species is one that by its presence by its absence or by its relative abundance can help us understand the health of an ecosystem or the health of an aspect of an ecosystem we did an example of this in video one where we talked about lichens lichens are sensitive to sulfur dioxide they die when they're exposed to too much of it or exposed for it for too long sulfur dioxide is produced by coal burning power plants and it's one of the main causes of acidic precipitation by tracking the health of lichens in an area we can also make inferences about air quality and acidic precipitation there so this indicator species is telling us by its presence absence a relative abundance what's going on with air quality in an area that's what an indicator species is what's rlf rlf is replacement level fertility it refers to the number of children women in a population must have to sustain population levels it's about two in developed nations a little more about 2.1 but it's higher in developing nations like niger is around seven for rlf because niger has a really high infant and child mortality rate so that women have to have more children in order to offset the children that are dying before age five are all generalists are selected so in reality most species in the real world fall somewhere between all the way r and all the way k selected generalists are usually closer to our selected and for this course we're going to go along with that kind of rule of thumb all right here's a specific one for a free response model one from video two and just to refresh you how to mitigate the negative effects of human population growth on forests could selective cutting be an appropriate or okay answer thank you for asking very specific and i love it the answer to that is yes selective cutting is actually part of sustainable forestry techniques and that was the first answer discussed so sometimes the rubric shortcuts this stuff so if you mentioned a specific sustainable forestry technique and you described it correctly because the prompt asks you to describe it then yes it would have been pointable you could have said sustainable forestry techniques or mentioned a specific sustainable forestry technique so yes perfect wonderful and i am proud of you because y'all's brains are getting so strong yay [Music] all right just some exam information reminders so if you're joining us for the first time today please please please take a moment to watch ap daily live video one for important information regarding exam dates and exam formats this is really important stuff and i want you guys to be prepared for whatever type of exam you're taking so that you can launch off wonderfully all right and as always i'm going to provide you with the helpful links for exam information if this is your first time here if you need information about general exam dates and times there's your url if you need information specifically about the ap environmental exam there's your url if you are taking the digital exam and you're not sure what to expect there's your digital testing guide right there now some of that is you know with student-friendly and some of that pertains to people that aren't students so take that with a little bit of grain of salt there and then the preview of the digital exam including how to get your device ready and the practice app is available at this app i'm also going to go ahead and mention there is a youtube video by the college board that is giving that will give you information about the digital exam and how to get yourself ready you can actually just search it up it's right there in the in the channel for the college board so give it a try take a look um get all your stuff that you need to get all right so let's do some content review for earth systems and i know like this is sometimes kids are like what the what coriolis effect huh what thermo salon circulation huh but trust me this guy was going to be a geologist so you're in good hands let's get started all right plate tectonics plate tectonics is the theory explaining the movement of earth's rigid lithospheric plates that's the result of convection processes convection processes in the underlying partially molten mantle right so the plates are moving because there's convection that's spreading them apart or bringing them together due to the result of the the molten mantle this is um a little map of our lithospheric plates here on earth these lithospheric plates have distinctive features where they either come together which is converging pull apart which is diverging or push against each other i want to talk about each of those convergent boundaries occur where two plates come together two plates come together features of convergent boundaries depend on the types of crusts that are converging oceanic or continental oceanic or under the oceans and continental are under the continents and their relative densities convergent boundaries create mountains island arcs earthquakes and volcanoes and you need to be able to identify those on a map so be sure you can identify the geographic examples of convergent boundaries on a world map like island arcs volcanoes and mountains island arcs there in the pacific japan down to indonesia volcanoes in the pacific northwest and the andes divergent boundaries occur where two plates are pulling apart pulling apart divergent boundaries can result in seafloor spreading rift valleys and also earthquakes and volcanoes transform boundaries occur where two plates are trying to slide past each other usually horizontally we're at an angle but they're not diverging and they're not converging they're trying to kind of slide past each other and they're under pressure transform boundaries often result in earthquakes earthquake occurs when the stress on these lithospheric plates overcomes a fault that is locked resulting in a slip and a release of energy be sure you can identify geographic examples of divergent boundaries on a world map like this seafloor spreading in the mid-atlantic rift yes i know that that circle looks like it's circling nothing but that's the mid-atlantic rift and the rift valley in east africa and be sure that you can identify geographic examples of transform boundaries on a world map earthquakes occur that's the san andreas fault and earthquakes are occurring there in the himalayas as well now obviously there's a lot more examples geographically that we could give for each one of these faults so these aren't the only ones that you could see i'm just given a couple of overview examples all right let's talk about soil so it's a jump from lithospheric uh plates to soil but soil is really the connection between these abiotic lithospheric plates and the living biosphere that were that we're going to study soil is formed when parent material is weathered transported and deposited soils are categorized by horizons based on composition and organic content yay soil horizons so um here this is like a cross section of a soil horizon we've got our organic layer or o horizon at the top top soil which is our a horizon comes next i'm going to skip the e for right now b is our subsoil and c is the partially weathered parent rock not all soils have an e layer it depends on the climate and it also depends on the age of the soil but you might actually see an e-layer on the exam as well soils are of course an important natural resource that must be protected and there's a lot of questions that pertain to soil health soil erosion because soil really is that link between biotic and abiotic conditions soil can be eroded by wind and water and the protection of soil from erosion can actually help protect water quality because soil helps to filter and clean water ecosystem service and soil erosion into bodies of water can create turbidity it can also reduce the penetration of sunlight which reduces photosynthesis which of course is the basis of the trophic structure in an ecosystem and it can clog the gills of aquatic organisms the soil is pretty darn important in ap environmental science so you do a good favor to yourself by going back and reviewing your soil stuff all right different types of soil have different physical and chemical properties water holding capacity is the total amount of water that a soil can hold different soil types have different water holding capacities depending on their texture the percentage of sand silt and clay and we're going to get to that in a minute and their organic content the ability of a soil to retain water contributes of course to agricultural productivity and we'll talk more about that in unit 5 tomorrow soil texture can affect porosity permeability and the fertility of a soil hey it's a soil triangle texture is quantified by the amount of sand down there at the bottom silt right hand side and clay on the left-hand side particles that a soil contains you do need to know how to read a soil triangle this is in our unit 4 videos we'll take you through it so please please please if this is if this is the first time you've seen a soil triangle and your mind is blown go go back and look the physical chemical and biological properties of soil can be tested by various methods hint experimental design soil tests can help determine agricultural irrigation needs and fertilizer requirements there's your soil texture triangle and it can help you identify the type of soil based on its texture or its percentage of sand silt and clay all right let's move from soil to the atmosphere earth's atmosphere is made of about 78 nitrogen 21 oxygen and about one percent other gases including carbon dioxide and water vapor this is a little side view of the temperature gradients of the atmosphere the layer the layers of the atmosphere are based on temperature gradients the troposphere let's talk about the troposphere if you look at the diagram there the troposphere is the layer that is closest to the earth the temperature in the troposphere drops with altitude meaning it gets colder as we go higher the all weather happens in the troposphere so if we're talking about weather we're talking about the troposphere so your water vapor your clouds all the weather has happened in the troposphere it is also your most dense atmospheric layer because the most particles exist here the particles of air exist here the stratosphere is above the troposphere this is where the ozone layer is located and you can kind of see this in the diagram and that little s that little straight up and down in the lower stratosphere is where the ozone layer is but above the ozone layer the temperature of the stratosphere actually increases with altitude and you can see that that zigzags back from the troposphere there is very little horizontal or vertical mixing of the particles within the stratosphere so what goes up there gets stays up there and that has some implications when it comes to um chlorofluorocarbons and and bromated fluorocarbons and all that good stuff it is less sense than the troposphere there is less atmospheric particles up there and we got the mesosphere and you can see that the mesosphere actually also gets colder with altitude as we go up it gets colder we've got the thermosphere and finally the exosphere the exosphere is our least dense and it fades off into space um the troposphere and stratosphere are going to be your biggies for environmental science and you do need to know what happens there global wind patterns are the result of differential heating of the earth's surface by the sun yay global wind patterns the most intense solar radiation arrives at the equator causes surface heating which leads to density differences in the air and these different density differences lead to our tri-cellular model of atmospheric circulation so let's talk a little bit about that tricely model so we have this direct incoming solar radiation at the equator and this warm air rises at the equator and it condenses and spreads out and this is due to the rotation of the earth take a look at this picture right here this is a diagram of a hadley cell so you can see there at the equator you've got really intense solar radiation that warm surface air rises and then it spreads out uh to the north and to the south away from the center line of the equator the precipitation from this condensation falls between 30 0 and 30 degrees north and south latitude that's our that's our latitude for our hadley cell right and that creates a tropical rainforest biome in that 0 to 30 degrees north and south latitude you can see there that the red obviously indicates warm moist air and the blue indicates cool dry air so at 30 degrees north and south latitude that cooler drier air comes back down to the surface and that has implications for climate there at 30 degrees north and south latitude we find many of earth's major deserts and that is because the cooler drier air from the hadley cell descends at those latitudes this pattern of heating rising condensing precipitation and descent also occurs at our mid-latitudes those are our feral cells and at the poles which are the polar cells so just a quick reminder if you can't remember which one's which um here's a little memonic the hadley happens where it's hot at the equator hadley is hot all right large air masses are influenced by earth's rotation it's spinning on its axis the deflection of air masses from a true northward or true southward path due to this rotation is called the coriolis effect objects any object including air masses are deflected to the right in the northern hemisphere and to the left in the southern hemisphere due to the coriolis effect the spinning of the earth on its axis the spinning of cyclonic storms which is counterclockwise in the northern hemisphere and clockwise in the southern is also the result of the coriolis effect all right we're moving from the atmosphere back down watersheds or drainage basins are discrete areas that drain all of the streams and precipitation in an area to a common outlet whatever that outlet happens to be it could be a lake it could be the ocean this is what a watershed looks like okay so we've got rainfall and you can see that there's lots of stuff going on here there's a river there's got groundwater infiltration there's some farms there's forests there's a lot going on here there's a town characteristics of a given watershed include its area its length the slope does it have a high slope or a low slope the soil types that underlay it vegetation types and divides or boundaries with other watersheds watersheds and water quality of course are affected by human activities we're going to actually model this with a free response question today incoming solar radiation which is also called insolation is the not insulation like in your attic but insolation incoming solar radiation is the main energy source for nearly all earth processes the intensity of insulation varies by season and by latitude because these factors affect the angle of the incoming rays all right so this is a little graphic talking about the angle of incoming solar radiation so let's pretend that the sun is a flashlight like and if you have a piece of paper and you shine your flashlight directly right you get a nice round uh piece a nice round uh beam of light there but if you tilt your paper right you're going to have an oblique angle there and so the same amount of incoming solar radiation is going to have to uh spread out over a greater geographical area so at any given area your intensity will be lower the earth is a sphere surprise it's a sphere so the equator receives the most intense solar radiation since it's mostly horizontal to the incoming rays at each latitude away from the equator both north and south the intensity of this insulation lessens so the poles north and south have the least intense solar radiation the tilt of the earth's axis causes the seasons there she blows tilt it also determines the amount of daylight and darkness in a particular location during a particular season on earth and again we will practice this today along with the intensity of incoming solar radiation climate in an area is affected by geographic features and these include mountains and proximity to large bodies of water normally warm surface air rises and cools as it moves up into the troposphere but we have a phenomenon called a thermal inversion a thermal inversion occurs when cooler air at the surface becomes trapped by a layer of warmer air above it remember that this is all caused by density differences and warmer air rises and so that's going to stay on top of your more dense cooler air this is a problem because thermal inversions increase the intensity of surface air pollution it traps the ability of that air pollution to rise up into the troposphere and spread out and thermal inversions are more common in areas that are surrounded by mountains so again geographic features are going to influence the intensity of your thermal inversions let's talk about rain shadows a rain shadow is a drier area of land adjacent to or in the shadow of a higher elevation the higher elevation like a mountain blocks the precipitation from reaching this area and there's a picture that's the big island of hawaii and you can see that one area is very green and lush and the other side is actually kind of brown and dry and that is your rain shadow side so the precipitation is falling on one side and then all of the by the time the air gets to the downward slope all of its moisture is gone ocean surface temperatures help to drive oceanic circulation patterns surface temperatures fluctuate in part due to changes in the prevailing winds which we talked about a few slides ago so two things that you need to know are el nino and la nina conditions the el nino southern oscillation or enso is a periodic non-anthropogenic phenomenon that means it's not created by man and it occurs in the southern pacific ocean so what we would call the normal conditions would be our la nina conditions but i don't want to really classify as normal or abnormal because el nino is just a periodic naturally occurring event however it does cause disruptions during el nino events changes to patterns of rainfall wind and ocean circulation occur that can cause significant climatic environmental and economic disruptions so basically what happens here is the prevailing winds coming off the co over the andes and through the the plains of south america weaken and when they do um they do they're not able to push this warmer surface water across the south pacific over to australia and the indonesian area normally we've got these strong surface winds that push our warm surface water across to the opposite side of the pacific so we get our cold upwelling that comes from the deeper layers we've got this thermocline and our cold upwelling brings nutrient-rich waters to the coast of south america which helps the fishing grounds there it also makes sure that that that warm moist air that's needed for precipitation across in australia and the indonesian area gets pushed over that way keeps those conditions drier the coast of south america but when those prevailing winds weaken then our thermocline declines we don't have that upwelling and our warm moist surface air um gets trapped here over the coast of south america we have wet conditions things prone to mudslides there and then we also have a lack of fishing because those those cold nutrient-rich waters don't come up on the coast so you do need to know what happens for climatic environmental and economic disruptions during an el nino event all right so let's talk about skills associated with this unit remember that any skill can be tested in any unit but there are certain units that lend themselves to certain skills so practice one concept explanation watersheds practice two there's a lot of practice two in unit four i wanna talk a lot about that plate tectonics earth's atmosphere global wind patterns solar radiation and the earth seasons earth's geography and climate practice for scientific investigations soil formation and erosion soil composition and properties and finally our environmental solutions where we're providing solutions and justifying those el nino and la nina all right let's take a look at our first example for today the diagrams below illustrate seasonal variations in global wind direction so i'm going to start with this this unit is visual model heavy and these visual models can be overwhelming when you first look at them you look at this and you're like what is happening here so we need to take them apart so that we can understand what is happening here and look at what the prompt is telling us and hone in on exactly what's going on don't get overwhelmed they deep breath okay so seasonal variations in global wind direction so we've got one that's for january and one that's for july okay we're ready to go question one based on the information in the diagrams describe the seasonal changes in global wind patterns between january and july at location one all right so first we gotta find january location one all right got it then we gotta find july location one got it so location one is india right and we've got uh january and july so the arrows are showing us our wind patterns so what's going on with the winds in january well they come they look like they're coming off the continent they're kind of out through the deccan plains and and down into kind of moving down from the from the continent down into the indian ocean and then in july they're going the opposite way all right cool so in january the winds at location one come from the north and in july the winds at location one come from the southwest and all you're doing there is describing what direction those arrows are showing don't get overwhelmed all right based on the information in the diagrams explain why the days at location five there it is have more hours of daylight in december than the days in location two have in december so we're talking december we're in the southern hemisphere okay so there's our equator december is summer in the southern hemisphere so location five will have more hours of daylight than location two due to the tilt of the earth at that time you could also say due to the angle of the incoming sunlight right so you got to remember in the southern hemisphere we've got our seasons reversed wow for us in the northern northern hemisphere if you're in the southern hemisphere they're normal or location 5 is near the south pole where the sun never really sets during the summer which is december for them location two is closer to the equator so we'll have less daylight during december all right based on the information in the diagrams explain how the seasonal wind direction could affect local weather at location one so we're talking about weather right and we're talking about location one so we're back to location one and we're talking about seasonal wind direction so we've gotta compare january and july all right in january the winds at location one are coming of course down off the continent so winds coming off a continent are going to be bring cooler and drier air but this location is pretty close to the equator so the weather will still be relatively warm because it's close to the equator in july the prevailing winds are coming up off the indian ocean which is going to make the weather hot and humid okay for winds in the southern hemisphere that blow out of the south and are directed northward towards the equator as shown in the diagrams and this is what the arrows show boop identify the direction towards which they are deflected and explain why this deflection occurs okay we're talking coriolis effect here so here we go in the southern hemisphere winds blowing northward will be deflected to the left which is westward and the deflection is due to the coriolis effect now do you have to describe the coriolis effect nope you have to explain why the deflection occurs and it is the result of the coriolis effect which is that deflection is is due to the earth spinning on its axis every few years in the southern hemisphere the winds over the pacific ocean as shown in the diagrams weaken or reverse direction describe the typical change to the weather pattern that happens along the northwestern coast of south america during those years so if you've been following along this is going to be an el nino question so first orient yourself on the map right so we're talking about um the coast of the northwestern coast of south america and we i had mentioned that those prevailing winds weakened a reverse direction so prevailing winds weaken periodically due to the enzo that el nino southern oscillation when this happens there's an increase in the temperature and the amount of rain because surface temperature of the water stagnates and increases the weather is warmer and there are more storms there can be major flooding in parts of south america which sometimes leads to pretty severe mudslides all right so any of those right you're going to you're going to kind of describe what happens during an el nino southern oscillation event so again you might want to go back and take a look at that um in your content all right all of these parts that we just went through a through e are visual representations they are based on analysis of a map um that you are taking a look at and again this is uh unit four is visual representation heavy all right so describe an economic problem that's the result of the weather change that you described in part e so what's an economic problem that happens due to el nino this is concept explanation since el nino events cause warmer weather and heavy rains in coastal south america and they reduce cold water upwelling along the coast any of the following economic issues could occur we could have a reduction in fishery production we could have a reduction in fertilizer production like what well less crops are being grown so less need for fertilizer we could have property damage from flooding or property damage from landslides there will be a decrease in tourism because of flooding landslides or maybe just a lack of fishing we might have damage to crops from extreme weather any of those could be economic issues finally increased health care costs or loss of productivity meaning that people aren't working from the spread of vector-borne or water-borne infectious diseases if the water is stagnant you're going to have more malaria dengue fever or any warmer waterborne diseases they would increase in this area all right identify a characteristic of the expected climate on the slope of a mountain farthest from the ocean when the prevailing winds carry air from the ocean over land up the slope of a mountain and down over the other side rain shadow they literally described it for you the okay so the the expected climate on the slope of a mountain furthest from the ocean will be cooler and drier that's the definition of the rain shadow okay finally a community is we're heading over here to um experimental design a community is considering switching from coal-fired plants using wind energy to generate electricity in order to decide what type of wind turbine is best for the area an investigation was concluded are conducted to compare the amount of electricity generated using different blade lengths a series of wind turbines were assembled at a location at a location near the community and tested to compare the amount of electricity each wind turbine could produce care was taken to make sure that each turbine was positioned to be exposed to the same wind direction and speed so those are our constants all right other than positioning the turbines to be exposed to the same wind direction and speed identify a variable that would have been held constant in this investigation all right again here we are in practice four remember that constants and an investigation are the factors that must be identical in each trial so that the researcher is certain that the results observed come only from the manipulation of the independent variable so and a variable could be the height of the turbine the material of the turbine the number of the turbine blades the width of the blades the angle or the pitch of the blades and the duration of the test all of these must be held constant or you can't be sure that you're getting results from what you think you are identify a hypothesis for the investigation okay the wind turbine with the longest blades will generate the most electricity or the wind turbine with blades that are balanced between length and mass will generate the most electricity or blade length will have no effect on the amount of electricity generated null hypothesis is always fine describe how a proposed change from coal to wind could decrease the ecological footprint of the community all right so ecological footprints are topic 5.11 we've asked about these several times in the past so um good to review it so switching from coal-fired power plants to wind energy would reduce an ecological footprint by reducing the phospho fuel combustion our greenhouse gas emissions reducing the mining processes needed to extract coal reducing acidic precipitation or deposition because the reduction of burning coal results in reduced sulfur emissions all right so we're going to go a little faster through the second one you kind of got the idea and this one is fairly similar in the terms of how it's structured here we go it's a diagram it shows a watershed around an underground underground mine steam stream three runs from the top of the mountain down to the lake the entire watershed is underlaid by bedrock that contains some metal there's a town on the lakeshore that's concerned because there are there's an increasing amount of metal contaminants in the lake so we're gonna again this is a very detailed visual model and we're going to take it apart all right here we go based on the diagram describe how human activities could have increased the amount of metal contaminants in stream four so first off let's find stream four there it is okay notice that it's close to the mine stream four is adjacent to the mine and exposed mine tailings which you see there in the picture the metals could leach out of the tailings and into the stream okay same uh same uh diagram that we're working on explain why stream one would have less suspended sediment than stream two first off let's orient ourself there's stream one and there's stream two all right so you notice that stream one has an intact forest next to it and stream two has a clear-cut forest stream two runs through a clear-cut forest clear cutting increases soil erosion and sediment deposition so the stream's gonna have more suspended than sediment than stream one but stream one also meanders more the word meander means to weave back and forth and stream one meanders more than stream two and meandering streams are less prone to bank erosion than straighter streams so stream one might have less suspended sediment than stream two due to that either one of those are acceptable same diagram different prompt based on the diagram make a claim using evidence that a regulating ecosystem service has been devalued as the result of human activities now we modeled this in the beginning so here we go with the actual model that you can see so we need a regulating ecosystem service right and we need to talk about the devaluation of that so when we look at this diagram the best choice for this answer right is our clear-cut forest this is topic 2.2 which is regulating ecosystem services so intact foresters forests offer many regulating surfaces clear cutting trees devalues those surfaces and these include erosion control filtration of air and water flood control carbon sequestration or pest mitigation so when you clear cut a forest you devalue its regulating service same diagram different prompt describe how the precipitation at high elevations would impact sedimentation in the lake so here's our rain up at high elevations lake is down below what's going to happen when it rains up top down in the lake well precipitation at high elevations will cause increased soil erosion downslope right which is going to lead to increased sedimentation down in the lake and this actually may be this process may be increased due to the clear cutting that you see around stream two explain how soil composition may affect levels of metal contamination in the area now caveat when you look at this diagram here they don't tell you anything really about the soil uh composition in the area so you have to kind of go with what you know about soil composition here so smaller soil particles like clay have a greater ability to hold onto metals so if the soil has a high proportion of clay which you don't know based on this diagram there may also be a higher level of metal contamination in the area so this is based on what you already know about soils some of the miners assess assert that the area in which the ore is being mined must have been located at a convergent plate boundary make a claim using evidence from the diagram that supports or opposes the minor's assertion okay there's our same visual prompt okay okay let's take a look well if you're gonna support the miners claim you can see that there's a volcanic rock right there in the um in the visual volcanic rock can form at a conversion plate boundary because we said volcanoes of course are a feature convergent plate boundaries and notice that there's an elevation change there so mountains can also form a convergent plate boundary so you do have evidence of that in the graph but you could also refute the miners claim because you know what volcanic rock can also form at a divergent plate boundary so you can give evidence from the graph for either supporting or refuting the miners claim all right a through f here again visual representations and that's pretty heavy in this unit all right the mining company claims that they cannot extract enough ore from the mine and wants permission to convert the mine into a strip mine other than the extraction of ore describe an advantage to converting the mine into a strip mine okay well strip mining is less hazardous to miners than subsurface mining people don't have to go underground they don't have to breathe coal dust less hazardous strip mining is less expensive than subsurface mining due to labor costs health care costs for minors and increased efficiency strip mining results in greater production rates than subsurface mining and any of those would be evidence right to um to describe for describing an advantage to converting your mind the subsurface mind that you see in the in the diagram into a strip mine all right last little bit here and that of course is our experimental design scientists are interested in investigating the possibility that plants can be used to remove heavy metals from contaminated soil phytoremediation they divide a sample of soil with heavy metal contamination into five different pots and plant five different species of grass they believe will take metal up into their roots and leaves they also plant the same grasses in five pots with uncontaminated soil after allowing the grasses to grow for a month they cut the grass and then measure the concentration of metals in milligrams per kilogram what's the control and what's a valid hypothesis those are both scientific investigation questions so remember that the control group is going to be the group that's closest to the normal conditions or receives no treatment and that of course would be the group of plants growing in the uncontaminated soil a good hypothesis for the investigation i want to model this really quickly you could say different species of grasses will remove different will remove heavy metals from contaminated soil at different rates but if you want to put it in an if then i gave this to you too if different species of grasses are grown in contaminated soil then the grasses will remove heavy metals from the soil at different rates do you have to do if then no but if you're used to doing that in your science classes that's a way to take that answer and model it and if then finally after determining the species of grass that removes the most metal it is planted in the area that was logged in addition to removing metals from the soil describe an advantage to the soil of planting grass in the area well when you plant grass you decrease soil erosion easy peasy yay all right so what should we take away things to remember when answering free response questions with a visual model as a stimulus you must be sure to reference the model in your answers as you read a prompt with an experimental setup determine the independent and the dependent variables even if the question doesn't ask you to identify these because this is going to help you mentally frame the setup of the experiment complex wording of a question doesn't necessarily indicate that the question is looking for a complex answer so take it apart visual models for unit 4 may be detailed and they can seem overwhelming at first glance take a breath read the prompts and look closely at the diagram and you'll realize they're not as scary as you think all right questions where can i provide more information clarification and all that good stuff here's our wonderful google feedback form and your qr code for that i'm always always interested in your feedback it makes things better and i'd love to answer your questions and again of course you might get a shout out at the beginning of next video so be sure to tune in uh daily video for preview we're gonna have clarifications and answers to submitted questions for ap daily live video three which was today content review for land and water use which is unit 5 free response modeling focused on connecting content knowledge with our science practices which we've been doing all week and interactive practice on concepts in video 4. so join our kahoot to test out what you know from today's video test what you got folks there's your kahoot link and your qr code today's game pin is zero zero six zero seven four four four eight let's see how you do let me give that to you for a sec let you grab it all right thanks for watching everybody and i'll see you tomorrow bye

hey everyone welcome back it is day three ap daily live ap environmental science thanks for being here for the third day in this series i&#39;m going to go ahead and start my screen so before we get started let me reintroduce myself my name is lisa bagley i teach in texas right outside of dallas mesquite isd go wranglers what are we going to learn today well funny you should ask on this earth day eve in ap daily live video 3 we&#39;re going to answer questions and provide clarification of concepts from video 2. we&#39;re going to conduct a brief overview of content for unit 4 earth systems and resources we&#39;re going to practice connecting our free response questions to answers uh free response question answers to the science practices in order to maximize score potential and we&#39;re going to wrap up with questions and a link to some live practice just a reminder on what these videos are for and how to use them ap daily live videos are designed to help you understand how to demonstrate your environmental science content knowledge via the essential science practices the college board expects you to know these are not specifically content review videos however the ap daily content videos that are presented in the units discussed for each of the review videos will be referenced during the presentations i want to clarify that just a little bit um for this particular unit and whatever unit we&#39;re talking about this happens to be unit four um if the content pertains to unit four i will not reference that video because those are those videos because we have just gone over that content but if the content comes from outside of the unit four videos then those videos will be referenced during the free response uh question modeling portion of the videos i&#39;ll point out common pitfalls that students often make when answering these exam questions and offer suggestions on how to avoid these and to maximize your scoring potential and as always the videos are best used in conjunction with individual review on your own time because of course you know best what you need to work on so first let&#39;s jump into questions and clarifications from this should say video video uh two this is going to be a video two clarifications so um again i want to thank everybody y&#39;all are really amazing when it comes to giving feedback and suggestions like it&#39;s really really good and i want to give a shout out to everybody about that so the the first one i want to hit is can you go over the format of the exam please well thanks for asking we did that um back in video one of the series the exam specifics were discussed in detail so if you still need to figure out what is going on with the specifics of the exam please take a look at video one the first part of that video does talk about that in detail all right several of you were questioning about if i&#39;m a paper test taker how do i organize my free response questions and what if i need to skip and come back to a section so shout out to preston h from utah for asking that question the organization of free response questions on the paper exam is best done in the same order as the questions so um for answer for example if you know you&#39;re answering question uh prompt a putting prompt at you know putting the a in parentheses and then answering it that&#39;s the easiest way for a reader to figure out what you&#39;re talking about where your points are however that said if you need to skip a section and come back you can either leave some blank space and then come back and write there or you can put the skipped section at the end of your answer to that question but make sure you label it it just makes it easier for us to find your points when we&#39;re scoring it math math and more math lots of questions about the math so can my math setup be different than the model and still earn points the answer to that is yes it can the math setup can be different and you can still earn points but the bottom line is that your ap reader must clearly be able to see both your units in the setup and the answer and they must be able to logically follow your math steps to arrive at the answer that you&#39;ve given there if the math is not like if the math is not followable is that even a word if the math is not followable or you don&#39;t have what&#39;s required which are units in setup and answer then it would not be pointable several of you asked for significant figures as for sig figs there&#39;s no hard and fast rule usually two sig figs is plenty on the apes exam and no you do not have to put your answer into scientific notation several of you guys were like hey i have this in non-scientific notation because scientific notation freaks me out cool it doesn&#39;t matter as long as it&#39;s the same answer as we would get with scientific notation no problem whatsoever uh it just makes it easier for us to look at sometimes but still pointable several people asked about how do i show my map in the digital app so here&#39;s the deal with the digital app there&#39;s you&#39;ve got the practice app there so one of the things with the practice app is that they have practice problems that are loaded there and i&#39;m going to really highly suggest like really suggest that you guys practice in your digital app um putting those math equations in there just to see how you do it there&#39;s nothing in apes that can&#39;t be done on a keyboard in terms of math and of course you know you&#39;re going to be able to type your units or whatever so you&#39;ve got a mixture of you know keyboard commands like the divide sign or the multiplication the star for multiplication should be able to do all of that but practice practice so you&#39;re not going in cold all right so if we answer a free response question correctly but the answer isn&#39;t on the rubric do we still get a point um good question and the answer to that is it depends um if you&#39;re so if you if you have an off rubric answer uh we&#39;ll evaluate it uh during the reading and if it&#39;s deemed to be a legitimate answer to the prompt right then it&#39;s up to the question leader as to whether or not that will be pointed the decisions are actually made on an individual basis however if lots of examinations have a similar answer then that answer might actually be added to the scoring rubric as a modification um so generally speaking the rubric is set um but there there is some wiggle room if there is an frq answer that fits but it hasn&#39;t been identified on the rubric that&#39;s fairly rare however is there anything we should actually memorize for this exam this exam is not um really high on memorization i would suggest knowing some basic stats like how many people are on earth and what&#39;s the approximate population of the united states but in general this exam is really about the connection of concepts and phenomena rather than memorized facts and figures the questions that you&#39;re modeling are asking for solutions to environmental problems but i don&#39;t know these solutions where are they well the solutions to environmental problems are kind of scattered throughout the content of the course and that&#39;s according to unit so just a caveat units one through four don&#39;t have a lot of solutions to environmental problems and that is because of the nature of units one through four they&#39;re mostly focused on basic environmental science concepts right so so um the make a claim you&#39;ll see in a lot of these models that make a claim comes from other units in these in these first few units because there&#39;s not a lot of making a claim you&#39;re going to do with with certain ecology concepts or or systems concepts you&#39;ll we are going to see this pick up a lot in unit 5 and continue on through the rest of the videos throughout the rest of the course and unit 5 is going to be covered tomorrow in our live session on april 22nd so you&#39;re going to see how that unit how the content of that unit lends itself to environmental solutions and i&#39;ll point that out specifically all right so what would be an example of a social solution to an environmental problem i i had mentioned that you need to make sure that you&#39;re actually answering the type of solution that they&#39;re asking for well good question you could have an education or a public information campaign um citizen science initiatives like what lois gibbs did with love canal or aaron brockovich in hinckley california with you know toxic waste dumping or margie richard in norco louisiana so if you don&#39;t know who these people are those are great case studies you might want to look them up hey miss bagley can you model how a make a claim answer would look if you were to write it um thank you for asking in these videos i&#39;ve just kind of been giving you what the rubric prompt will look like but i haven&#39;t modeled exactly what a student response might look like so we&#39;re going to talk actually we&#39;re going to do several make a claims tonight so here&#39;s a modified one you know that i took from today&#39;s practice based on the diagram which you&#39;ll see later make a claim using evidence that a regulating ecosystem service has been devalued as a result of human activities okay so you&#39;ve got to make a claim you&#39;ve got to use evidence from the diagram and you&#39;ve got to specifically mention regulating ecosystem services three things you gotta hit here the diagram shows a forest that has been clear-cut near stream two intact forests provide humans with many regulating surfaces like erosion control and carbon sequestration so clear cutting a forest devalues the ecosystem services they provide i&#39;m telling you that i saw in the diagram that there is a forest that&#39;s been clear cut right and i know that intact forests provide ecosystem services and i gave an example of that and i&#39;m telling how the clear cutting would devalue those ecosystem services that hits all three of those okay so that&#39;s how it would look like in narrative format rather than rubric format all right hey what&#39;s an eco what&#39;s an indicator species again all right an indicator species is one that by its presence by its absence or by its relative abundance can help us understand the health of an ecosystem or the health of an aspect of an ecosystem we did an example of this in video one where we talked about lichens lichens are sensitive to sulfur dioxide they die when they&#39;re exposed to too much of it or exposed for it for too long sulfur dioxide is produced by coal burning power plants and it&#39;s one of the main causes of acidic precipitation by tracking the health of lichens in an area we can also make inferences about air quality and acidic precipitation there so this indicator species is telling us by its presence absence a relative abundance what&#39;s going on with air quality in an area that&#39;s what an indicator species is what&#39;s rlf rlf is replacement level fertility it refers to the number of children women in a population must have to sustain population levels it&#39;s about two in developed nations a little more about 2.1 but it&#39;s higher in developing nations like niger is around seven for rlf because niger has a really high infant and child mortality rate so that women have to have more children in order to offset the children that are dying before age five are all generalists are selected so in reality most species in the real world fall somewhere between all the way r and all the way k selected generalists are usually closer to our selected and for this course we&#39;re going to go along with that kind of rule of thumb all right here&#39;s a specific one for a free response model one from video two and just to refresh you how to mitigate the negative effects of human population growth on forests could selective cutting be an appropriate or okay answer thank you for asking very specific and i love it the answer to that is yes selective cutting is actually part of sustainable forestry techniques and that was the first answer discussed so sometimes the rubric shortcuts this stuff so if you mentioned a specific sustainable forestry technique and you described it correctly because the prompt asks you to describe it then yes it would have been pointable you could have said sustainable forestry techniques or mentioned a specific sustainable forestry technique so yes perfect wonderful and i am proud of you because y&#39;all&#39;s brains are getting so strong yay [Music] all right just some exam information reminders so if you&#39;re joining us for the first time today please please please take a moment to watch ap daily live video one for important information regarding exam dates and exam formats this is really important stuff and i want you guys to be prepared for whatever type of exam you&#39;re taking so that you can launch off wonderfully all right and as always i&#39;m going to provide you with the helpful links for exam information if this is your first time here if you need information about general exam dates and times there&#39;s your url if you need information specifically about the ap environmental exam there&#39;s your url if you are taking the digital exam and you&#39;re not sure what to expect there&#39;s your digital testing guide right there now some of that is you know with student-friendly and some of that pertains to people that aren&#39;t students so take that with a little bit of grain of salt there and then the preview of the digital exam including how to get your device ready and the practice app is available at this app i&#39;m also going to go ahead and mention there is a youtube video by the college board that is giving that will give you information about the digital exam and how to get yourself ready you can actually just search it up it&#39;s right there in the in the channel for the college board so give it a try take a look um get all your stuff that you need to get all right so let&#39;s do some content review for earth systems and i know like this is sometimes kids are like what the what coriolis effect huh what thermo salon circulation huh but trust me this guy was going to be a geologist so you&#39;re in good hands let&#39;s get started all right plate tectonics plate tectonics is the theory explaining the movement of earth&#39;s rigid lithospheric plates that&#39;s the result of convection processes convection processes in the underlying partially molten mantle right so the plates are moving because there&#39;s convection that&#39;s spreading them apart or bringing them together due to the result of the the molten mantle this is um a little map of our lithospheric plates here on earth these lithospheric plates have distinctive features where they either come together which is converging pull apart which is diverging or push against each other i want to talk about each of those convergent boundaries occur where two plates come together two plates come together features of convergent boundaries depend on the types of crusts that are converging oceanic or continental oceanic or under the oceans and continental are under the continents and their relative densities convergent boundaries create mountains island arcs earthquakes and volcanoes and you need to be able to identify those on a map so be sure you can identify the geographic examples of convergent boundaries on a world map like island arcs volcanoes and mountains island arcs there in the pacific japan down to indonesia volcanoes in the pacific northwest and the andes divergent boundaries occur where two plates are pulling apart pulling apart divergent boundaries can result in seafloor spreading rift valleys and also earthquakes and volcanoes transform boundaries occur where two plates are trying to slide past each other usually horizontally we&#39;re at an angle but they&#39;re not diverging and they&#39;re not converging they&#39;re trying to kind of slide past each other and they&#39;re under pressure transform boundaries often result in earthquakes earthquake occurs when the stress on these lithospheric plates overcomes a fault that is locked resulting in a slip and a release of energy be sure you can identify geographic examples of divergent boundaries on a world map like this seafloor spreading in the mid-atlantic rift yes i know that that circle looks like it&#39;s circling nothing but that&#39;s the mid-atlantic rift and the rift valley in east africa and be sure that you can identify geographic examples of transform boundaries on a world map earthquakes occur that&#39;s the san andreas fault and earthquakes are occurring there in the himalayas as well now obviously there&#39;s a lot more examples geographically that we could give for each one of these faults so these aren&#39;t the only ones that you could see i&#39;m just given a couple of overview examples all right let&#39;s talk about soil so it&#39;s a jump from lithospheric uh plates to soil but soil is really the connection between these abiotic lithospheric plates and the living biosphere that were that we&#39;re going to study soil is formed when parent material is weathered transported and deposited soils are categorized by horizons based on composition and organic content yay soil horizons so um here this is like a cross section of a soil horizon we&#39;ve got our organic layer or o horizon at the top top soil which is our a horizon comes next i&#39;m going to skip the e for right now b is our subsoil and c is the partially weathered parent rock not all soils have an e layer it depends on the climate and it also depends on the age of the soil but you might actually see an e-layer on the exam as well soils are of course an important natural resource that must be protected and there&#39;s a lot of questions that pertain to soil health soil erosion because soil really is that link between biotic and abiotic conditions soil can be eroded by wind and water and the protection of soil from erosion can actually help protect water quality because soil helps to filter and clean water ecosystem service and soil erosion into bodies of water can create turbidity it can also reduce the penetration of sunlight which reduces photosynthesis which of course is the basis of the trophic structure in an ecosystem and it can clog the gills of aquatic organisms the soil is pretty darn important in ap environmental science so you do a good favor to yourself by going back and reviewing your soil stuff all right different types of soil have different physical and chemical properties water holding capacity is the total amount of water that a soil can hold different soil types have different water holding capacities depending on their texture the percentage of sand silt and clay and we&#39;re going to get to that in a minute and their organic content the ability of a soil to retain water contributes of course to agricultural productivity and we&#39;ll talk more about that in unit 5 tomorrow soil texture can affect porosity permeability and the fertility of a soil hey it&#39;s a soil triangle texture is quantified by the amount of sand down there at the bottom silt right hand side and clay on the left-hand side particles that a soil contains you do need to know how to read a soil triangle this is in our unit 4 videos we&#39;ll take you through it so please please please if this is if this is the first time you&#39;ve seen a soil triangle and your mind is blown go go back and look the physical chemical and biological properties of soil can be tested by various methods hint experimental design soil tests can help determine agricultural irrigation needs and fertilizer requirements there&#39;s your soil texture triangle and it can help you identify the type of soil based on its texture or its percentage of sand silt and clay all right let&#39;s move from soil to the atmosphere earth&#39;s atmosphere is made of about 78 nitrogen 21 oxygen and about one percent other gases including carbon dioxide and water vapor this is a little side view of the temperature gradients of the atmosphere the layer the layers of the atmosphere are based on temperature gradients the troposphere let&#39;s talk about the troposphere if you look at the diagram there the troposphere is the layer that is closest to the earth the temperature in the troposphere drops with altitude meaning it gets colder as we go higher the all weather happens in the troposphere so if we&#39;re talking about weather we&#39;re talking about the troposphere so your water vapor your clouds all the weather has happened in the troposphere it is also your most dense atmospheric layer because the most particles exist here the particles of air exist here the stratosphere is above the troposphere this is where the ozone layer is located and you can kind of see this in the diagram and that little s that little straight up and down in the lower stratosphere is where the ozone layer is but above the ozone layer the temperature of the stratosphere actually increases with altitude and you can see that that zigzags back from the troposphere there is very little horizontal or vertical mixing of the particles within the stratosphere so what goes up there gets stays up there and that has some implications when it comes to um chlorofluorocarbons and and bromated fluorocarbons and all that good stuff it is less sense than the troposphere there is less atmospheric particles up there and we got the mesosphere and you can see that the mesosphere actually also gets colder with altitude as we go up it gets colder we&#39;ve got the thermosphere and finally the exosphere the exosphere is our least dense and it fades off into space um the troposphere and stratosphere are going to be your biggies for environmental science and you do need to know what happens there global wind patterns are the result of differential heating of the earth&#39;s surface by the sun yay global wind patterns the most intense solar radiation arrives at the equator causes surface heating which leads to density differences in the air and these different density differences lead to our tri-cellular model of atmospheric circulation so let&#39;s talk a little bit about that tricely model so we have this direct incoming solar radiation at the equator and this warm air rises at the equator and it condenses and spreads out and this is due to the rotation of the earth take a look at this picture right here this is a diagram of a hadley cell so you can see there at the equator you&#39;ve got really intense solar radiation that warm surface air rises and then it spreads out uh to the north and to the south away from the center line of the equator the precipitation from this condensation falls between 30 0 and 30 degrees north and south latitude that&#39;s our that&#39;s our latitude for our hadley cell right and that creates a tropical rainforest biome in that 0 to 30 degrees north and south latitude you can see there that the red obviously indicates warm moist air and the blue indicates cool dry air so at 30 degrees north and south latitude that cooler drier air comes back down to the surface and that has implications for climate there at 30 degrees north and south latitude we find many of earth&#39;s major deserts and that is because the cooler drier air from the hadley cell descends at those latitudes this pattern of heating rising condensing precipitation and descent also occurs at our mid-latitudes those are our feral cells and at the poles which are the polar cells so just a quick reminder if you can&#39;t remember which one&#39;s which um here&#39;s a little memonic the hadley happens where it&#39;s hot at the equator hadley is hot all right large air masses are influenced by earth&#39;s rotation it&#39;s spinning on its axis the deflection of air masses from a true northward or true southward path due to this rotation is called the coriolis effect objects any object including air masses are deflected to the right in the northern hemisphere and to the left in the southern hemisphere due to the coriolis effect the spinning of the earth on its axis the spinning of cyclonic storms which is counterclockwise in the northern hemisphere and clockwise in the southern is also the result of the coriolis effect all right we&#39;re moving from the atmosphere back down watersheds or drainage basins are discrete areas that drain all of the streams and precipitation in an area to a common outlet whatever that outlet happens to be it could be a lake it could be the ocean this is what a watershed looks like okay so we&#39;ve got rainfall and you can see that there&#39;s lots of stuff going on here there&#39;s a river there&#39;s got groundwater infiltration there&#39;s some farms there&#39;s forests there&#39;s a lot going on here there&#39;s a town characteristics of a given watershed include its area its length the slope does it have a high slope or a low slope the soil types that underlay it vegetation types and divides or boundaries with other watersheds watersheds and water quality of course are affected by human activities we&#39;re going to actually model this with a free response question today incoming solar radiation which is also called insolation is the not insulation like in your attic but insolation incoming solar radiation is the main energy source for nearly all earth processes the intensity of insulation varies by season and by latitude because these factors affect the angle of the incoming rays all right so this is a little graphic talking about the angle of incoming solar radiation so let&#39;s pretend that the sun is a flashlight like and if you have a piece of paper and you shine your flashlight directly right you get a nice round uh piece a nice round uh beam of light there but if you tilt your paper right you&#39;re going to have an oblique angle there and so the same amount of incoming solar radiation is going to have to uh spread out over a greater geographical area so at any given area your intensity will be lower the earth is a sphere surprise it&#39;s a sphere so the equator receives the most intense solar radiation since it&#39;s mostly horizontal to the incoming rays at each latitude away from the equator both north and south the intensity of this insulation lessens so the poles north and south have the least intense solar radiation the tilt of the earth&#39;s axis causes the seasons there she blows tilt it also determines the amount of daylight and darkness in a particular location during a particular season on earth and again we will practice this today along with the intensity of incoming solar radiation climate in an area is affected by geographic features and these include mountains and proximity to large bodies of water normally warm surface air rises and cools as it moves up into the troposphere but we have a phenomenon called a thermal inversion a thermal inversion occurs when cooler air at the surface becomes trapped by a layer of warmer air above it remember that this is all caused by density differences and warmer air rises and so that&#39;s going to stay on top of your more dense cooler air this is a problem because thermal inversions increase the intensity of surface air pollution it traps the ability of that air pollution to rise up into the troposphere and spread out and thermal inversions are more common in areas that are surrounded by mountains so again geographic features are going to influence the intensity of your thermal inversions let&#39;s talk about rain shadows a rain shadow is a drier area of land adjacent to or in the shadow of a higher elevation the higher elevation like a mountain blocks the precipitation from reaching this area and there&#39;s a picture that&#39;s the big island of hawaii and you can see that one area is very green and lush and the other side is actually kind of brown and dry and that is your rain shadow side so the precipitation is falling on one side and then all of the by the time the air gets to the downward slope all of its moisture is gone ocean surface temperatures help to drive oceanic circulation patterns surface temperatures fluctuate in part due to changes in the prevailing winds which we talked about a few slides ago so two things that you need to know are el nino and la nina conditions the el nino southern oscillation or enso is a periodic non-anthropogenic phenomenon that means it&#39;s not created by man and it occurs in the southern pacific ocean so what we would call the normal conditions would be our la nina conditions but i don&#39;t want to really classify as normal or abnormal because el nino is just a periodic naturally occurring event however it does cause disruptions during el nino events changes to patterns of rainfall wind and ocean circulation occur that can cause significant climatic environmental and economic disruptions so basically what happens here is the prevailing winds coming off the co over the andes and through the the plains of south america weaken and when they do um they do they&#39;re not able to push this warmer surface water across the south pacific over to australia and the indonesian area normally we&#39;ve got these strong surface winds that push our warm surface water across to the opposite side of the pacific so we get our cold upwelling that comes from the deeper layers we&#39;ve got this thermocline and our cold upwelling brings nutrient-rich waters to the coast of south america which helps the fishing grounds there it also makes sure that that that warm moist air that&#39;s needed for precipitation across in australia and the indonesian area gets pushed over that way keeps those conditions drier the coast of south america but when those prevailing winds weaken then our thermocline declines we don&#39;t have that upwelling and our warm moist surface air um gets trapped here over the coast of south america we have wet conditions things prone to mudslides there and then we also have a lack of fishing because those those cold nutrient-rich waters don&#39;t come up on the coast so you do need to know what happens for climatic environmental and economic disruptions during an el nino event all right so let&#39;s talk about skills associated with this unit remember that any skill can be tested in any unit but there are certain units that lend themselves to certain skills so practice one concept explanation watersheds practice two there&#39;s a lot of practice two in unit four i wanna talk a lot about that plate tectonics earth&#39;s atmosphere global wind patterns solar radiation and the earth seasons earth&#39;s geography and climate practice for scientific investigations soil formation and erosion soil composition and properties and finally our environmental solutions where we&#39;re providing solutions and justifying those el nino and la nina all right let&#39;s take a look at our first example for today the diagrams below illustrate seasonal variations in global wind direction so i&#39;m going to start with this this unit is visual model heavy and these visual models can be overwhelming when you first look at them you look at this and you&#39;re like what is happening here so we need to take them apart so that we can understand what is happening here and look at what the prompt is telling us and hone in on exactly what&#39;s going on don&#39;t get overwhelmed they deep breath okay so seasonal variations in global wind direction so we&#39;ve got one that&#39;s for january and one that&#39;s for july okay we&#39;re ready to go question one based on the information in the diagrams describe the seasonal changes in global wind patterns between january and july at location one all right so first we gotta find january location one all right got it then we gotta find july location one got it so location one is india right and we&#39;ve got uh january and july so the arrows are showing us our wind patterns so what&#39;s going on with the winds in january well they come they look like they&#39;re coming off the continent they&#39;re kind of out through the deccan plains and and down into kind of moving down from the from the continent down into the indian ocean and then in july they&#39;re going the opposite way all right cool so in january the winds at location one come from the north and in july the winds at location one come from the southwest and all you&#39;re doing there is describing what direction those arrows are showing don&#39;t get overwhelmed all right based on the information in the diagrams explain why the days at location five there it is have more hours of daylight in december than the days in location two have in december so we&#39;re talking december we&#39;re in the southern hemisphere okay so there&#39;s our equator december is summer in the southern hemisphere so location five will have more hours of daylight than location two due to the tilt of the earth at that time you could also say due to the angle of the incoming sunlight right so you got to remember in the southern hemisphere we&#39;ve got our seasons reversed wow for us in the northern northern hemisphere if you&#39;re in the southern hemisphere they&#39;re normal or location 5 is near the south pole where the sun never really sets during the summer which is december for them location two is closer to the equator so we&#39;ll have less daylight during december all right based on the information in the diagrams explain how the seasonal wind direction could affect local weather at location one so we&#39;re talking about weather right and we&#39;re talking about location one so we&#39;re back to location one and we&#39;re talking about seasonal wind direction so we&#39;ve gotta compare january and july all right in january the winds at location one are coming of course down off the continent so winds coming off a continent are going to be bring cooler and drier air but this location is pretty close to the equator so the weather will still be relatively warm because it&#39;s close to the equator in july the prevailing winds are coming up off the indian ocean which is going to make the weather hot and humid okay for winds in the southern hemisphere that blow out of the south and are directed northward towards the equator as shown in the diagrams and this is what the arrows show boop identify the direction towards which they are deflected and explain why this deflection occurs okay we&#39;re talking coriolis effect here so here we go in the southern hemisphere winds blowing northward will be deflected to the left which is westward and the deflection is due to the coriolis effect now do you have to describe the coriolis effect nope you have to explain why the deflection occurs and it is the result of the coriolis effect which is that deflection is is due to the earth spinning on its axis every few years in the southern hemisphere the winds over the pacific ocean as shown in the diagrams weaken or reverse direction describe the typical change to the weather pattern that happens along the northwestern coast of south america during those years so if you&#39;ve been following along this is going to be an el nino question so first orient yourself on the map right so we&#39;re talking about um the coast of the northwestern coast of south america and we i had mentioned that those prevailing winds weakened a reverse direction so prevailing winds weaken periodically due to the enzo that el nino southern oscillation when this happens there&#39;s an increase in the temperature and the amount of rain because surface temperature of the water stagnates and increases the weather is warmer and there are more storms there can be major flooding in parts of south america which sometimes leads to pretty severe mudslides all right so any of those right you&#39;re going to you&#39;re going to kind of describe what happens during an el nino southern oscillation event so again you might want to go back and take a look at that um in your content all right all of these parts that we just went through a through e are visual representations they are based on analysis of a map um that you are taking a look at and again this is uh unit four is visual representation heavy all right so describe an economic problem that&#39;s the result of the weather change that you described in part e so what&#39;s an economic problem that happens due to el nino this is concept explanation since el nino events cause warmer weather and heavy rains in coastal south america and they reduce cold water upwelling along the coast any of the following economic issues could occur we could have a reduction in fishery production we could have a reduction in fertilizer production like what well less crops are being grown so less need for fertilizer we could have property damage from flooding or property damage from landslides there will be a decrease in tourism because of flooding landslides or maybe just a lack of fishing we might have damage to crops from extreme weather any of those could be economic issues finally increased health care costs or loss of productivity meaning that people aren&#39;t working from the spread of vector-borne or water-borne infectious diseases if the water is stagnant you&#39;re going to have more malaria dengue fever or any warmer waterborne diseases they would increase in this area all right identify a characteristic of the expected climate on the slope of a mountain farthest from the ocean when the prevailing winds carry air from the ocean over land up the slope of a mountain and down over the other side rain shadow they literally described it for you the okay so the the expected climate on the slope of a mountain furthest from the ocean will be cooler and drier that&#39;s the definition of the rain shadow okay finally a community is we&#39;re heading over here to um experimental design a community is considering switching from coal-fired plants using wind energy to generate electricity in order to decide what type of wind turbine is best for the area an investigation was concluded are conducted to compare the amount of electricity generated using different blade lengths a series of wind turbines were assembled at a location at a location near the community and tested to compare the amount of electricity each wind turbine could produce care was taken to make sure that each turbine was positioned to be exposed to the same wind direction and speed so those are our constants all right other than positioning the turbines to be exposed to the same wind direction and speed identify a variable that would have been held constant in this investigation all right again here we are in practice four remember that constants and an investigation are the factors that must be identical in each trial so that the researcher is certain that the results observed come only from the manipulation of the independent variable so and a variable could be the height of the turbine the material of the turbine the number of the turbine blades the width of the blades the angle or the pitch of the blades and the duration of the test all of these must be held constant or you can&#39;t be sure that you&#39;re getting results from what you think you are identify a hypothesis for the investigation okay the wind turbine with the longest blades will generate the most electricity or the wind turbine with blades that are balanced between length and mass will generate the most electricity or blade length will have no effect on the amount of electricity generated null hypothesis is always fine describe how a proposed change from coal to wind could decrease the ecological footprint of the community all right so ecological footprints are topic 5.11 we&#39;ve asked about these several times in the past so um good to review it so switching from coal-fired power plants to wind energy would reduce an ecological footprint by reducing the phospho fuel combustion our greenhouse gas emissions reducing the mining processes needed to extract coal reducing acidic precipitation or deposition because the reduction of burning coal results in reduced sulfur emissions all right so we&#39;re going to go a little faster through the second one you kind of got the idea and this one is fairly similar in the terms of how it&#39;s structured here we go it&#39;s a diagram it shows a watershed around an underground underground mine steam stream three runs from the top of the mountain down to the lake the entire watershed is underlaid by bedrock that contains some metal there&#39;s a town on the lakeshore that&#39;s concerned because there are there&#39;s an increasing amount of metal contaminants in the lake so we&#39;re gonna again this is a very detailed visual model and we&#39;re going to take it apart all right here we go based on the diagram describe how human activities could have increased the amount of metal contaminants in stream four so first off let&#39;s find stream four there it is okay notice that it&#39;s close to the mine stream four is adjacent to the mine and exposed mine tailings which you see there in the picture the metals could leach out of the tailings and into the stream okay same uh same uh diagram that we&#39;re working on explain why stream one would have less suspended sediment than stream two first off let&#39;s orient ourself there&#39;s stream one and there&#39;s stream two all right so you notice that stream one has an intact forest next to it and stream two has a clear-cut forest stream two runs through a clear-cut forest clear cutting increases soil erosion and sediment deposition so the stream&#39;s gonna have more suspended than sediment than stream one but stream one also meanders more the word meander means to weave back and forth and stream one meanders more than stream two and meandering streams are less prone to bank erosion than straighter streams so stream one might have less suspended sediment than stream two due to that either one of those are acceptable same diagram different prompt based on the diagram make a claim using evidence that a regulating ecosystem service has been devalued as the result of human activities now we modeled this in the beginning so here we go with the actual model that you can see so we need a regulating ecosystem service right and we need to talk about the devaluation of that so when we look at this diagram the best choice for this answer right is our clear-cut forest this is topic 2.2 which is regulating ecosystem services so intact foresters forests offer many regulating surfaces clear cutting trees devalues those surfaces and these include erosion control filtration of air and water flood control carbon sequestration or pest mitigation so when you clear cut a forest you devalue its regulating service same diagram different prompt describe how the precipitation at high elevations would impact sedimentation in the lake so here&#39;s our rain up at high elevations lake is down below what&#39;s going to happen when it rains up top down in the lake well precipitation at high elevations will cause increased soil erosion downslope right which is going to lead to increased sedimentation down in the lake and this actually may be this process may be increased due to the clear cutting that you see around stream two explain how soil composition may affect levels of metal contamination in the area now caveat when you look at this diagram here they don&#39;t tell you anything really about the soil uh composition in the area so you have to kind of go with what you know about soil composition here so smaller soil particles like clay have a greater ability to hold onto metals so if the soil has a high proportion of clay which you don&#39;t know based on this diagram there may also be a higher level of metal contamination in the area so this is based on what you already know about soils some of the miners assess assert that the area in which the ore is being mined must have been located at a convergent plate boundary make a claim using evidence from the diagram that supports or opposes the minor&#39;s assertion okay there&#39;s our same visual prompt okay okay let&#39;s take a look well if you&#39;re gonna support the miners claim you can see that there&#39;s a volcanic rock right there in the um in the visual volcanic rock can form at a conversion plate boundary because we said volcanoes of course are a feature convergent plate boundaries and notice that there&#39;s an elevation change there so mountains can also form a convergent plate boundary so you do have evidence of that in the graph but you could also refute the miners claim because you know what volcanic rock can also form at a divergent plate boundary so you can give evidence from the graph for either supporting or refuting the miners claim all right a through f here again visual representations and that&#39;s pretty heavy in this unit all right the mining company claims that they cannot extract enough ore from the mine and wants permission to convert the mine into a strip mine other than the extraction of ore describe an advantage to converting the mine into a strip mine okay well strip mining is less hazardous to miners than subsurface mining people don&#39;t have to go underground they don&#39;t have to breathe coal dust less hazardous strip mining is less expensive than subsurface mining due to labor costs health care costs for minors and increased efficiency strip mining results in greater production rates than subsurface mining and any of those would be evidence right to um to describe for describing an advantage to converting your mind the subsurface mind that you see in the in the diagram into a strip mine all right last little bit here and that of course is our experimental design scientists are interested in investigating the possibility that plants can be used to remove heavy metals from contaminated soil phytoremediation they divide a sample of soil with heavy metal contamination into five different pots and plant five different species of grass they believe will take metal up into their roots and leaves they also plant the same grasses in five pots with uncontaminated soil after allowing the grasses to grow for a month they cut the grass and then measure the concentration of metals in milligrams per kilogram what&#39;s the control and what&#39;s a valid hypothesis those are both scientific investigation questions so remember that the control group is going to be the group that&#39;s closest to the normal conditions or receives no treatment and that of course would be the group of plants growing in the uncontaminated soil a good hypothesis for the investigation i want to model this really quickly you could say different species of grasses will remove different will remove heavy metals from contaminated soil at different rates but if you want to put it in an if then i gave this to you too if different species of grasses are grown in contaminated soil then the grasses will remove heavy metals from the soil at different rates do you have to do if then no but if you&#39;re used to doing that in your science classes that&#39;s a way to take that answer and model it and if then finally after determining the species of grass that removes the most metal it is planted in the area that was logged in addition to removing metals from the soil describe an advantage to the soil of planting grass in the area well when you plant grass you decrease soil erosion easy peasy yay all right so what should we take away things to remember when answering free response questions with a visual model as a stimulus you must be sure to reference the model in your answers as you read a prompt with an experimental setup determine the independent and the dependent variables even if the question doesn&#39;t ask you to identify these because this is going to help you mentally frame the setup of the experiment complex wording of a question doesn&#39;t necessarily indicate that the question is looking for a complex answer so take it apart visual models for unit 4 may be detailed and they can seem overwhelming at first glance take a breath read the prompts and look closely at the diagram and you&#39;ll realize they&#39;re not as scary as you think all right questions where can i provide more information clarification and all that good stuff here&#39;s our wonderful google feedback form and your qr code for that i&#39;m always always interested in your feedback it makes things better and i&#39;d love to answer your questions and again of course you might get a shout out at the beginning of next video so be sure to tune in uh daily video for preview we&#39;re gonna have clarifications and answers to submitted questions for ap daily live video three which was today content review for land and water use which is unit 5 free response modeling focused on connecting content knowledge with our science practices which we&#39;ve been doing all week and interactive practice on concepts in video 4. so join our kahoot to test out what you know from today&#39;s video test what you got folks there&#39;s your kahoot link and your qr code today&#39;s game pin is zero zero six zero seven four four four eight let&#39;s see how you do let me give that to you for a sec let you grab it all right thanks for watching everybody and i&#39;ll see you tomorrow bye

Transcript for:AP Environmental Science Day 3 Overview

Transcript for:
AP Environmental Science Day 3 Overview