all right let's move on to worldwide title patterns take a look at this figure here it's in your book what you'll see is that different cosines deal with different title patterns all right so we've got three different title patterns that i want you to know that we're going to get into diurnal okay look here you can see the gulf there there's there's a diurnal title pattern also up here everywhere where it's yellow those are diurnal title patterns okay you can come back to this after we talk about what diurnal means then semi-diurnal you'll see oh right along you know in uh central america and then into south america as well as all through africa right you'll see semi-diurnal okay new zealand as well right and then mixed oh that's what we've got okay mixed tides perfect now we get it all right so that's where they are throughout the world okay and you can see that there's different title patterns throughout the world all right if you focus in on where we live this is what i want you to know i want you to know that the west coast of the united states has mixed tides okay check it out mixed tides blue is mixed right now i want you to know the east coast united states has semi-diurnal tides okay semi-diurnal tides and then i also want you to know that the gulf right here has diurnal tides so west coast mixed east coast semi-diurnal golf diurnal now what do those mean what in the heck do those mean all right here we go title patterns notice this is a i want you to look at all three of these figures here okay we got a high tide here okay low tide here so the y-axis is all about the height that the tide is all right and the x-axis here is in time so this is a zero to 24-hour scale but we've got to add 50 minutes because of that lag time because the moon is orbiting the earth and we got to catch up to it right that extra 50 minutes so what we got going on here is we got one high tide one low tide and then back to a high tide so we got one high tide one low tide per 24 hours all right in this one we've got one high tide one low tide oh two high tides two low tides and then we're back to square one so this and this are the same therefore two highs two lows and they're the same highs and lows in this case we've got a high tide a low tide another high tide another low tide and then we're back to where we started okay notice that this high tide is different from this high tide this is kind of a high high tide and this is kind of a mid high tide this one's a low low tide this is kind of a mid low tide all right so what is diurnal diurnal is one high and one low per tidal day this is happening in the gulf of mexico right that's what i said into the gulf here's the gulf of mexico that's diurnal now how about this next one semi-diurnal we got two highs one two two lows one two back to exactly the same high tide so we don't count this one per tidal day meaning 24 hours and 50 minutes the successive highs and lows are of similar height notice high tide and high tide are pretty much exactly the same they're on the same height as well as the low tide same height okay mixed we've got two highs and two lows per tidal day but the successive highs and lows are different heights okay so this is what we have here on the west coast united states semidiurnal this is on the east coast so look at the high tide and the high tide they're at different heights see that and the low tides are at different heights as well that's a mixed title pattern so now those are the three title patterns i want you to know and you will be asked questions on those see here i put low low high high now um if we looked at a uh graph of the tides around here okay so this is for like the west coast the united states for california we've got height once again this is in feet so zero three six all right and uh the zero here represents just what they decide to be the mean low low water okay we'll talk about that a little bit but it's just kind of something we decided and what you'll see here right the general so this is let's just get into it now the general term to describe the zero point so zero right here that red line is uh the mean lower low water okay it's not mean sea level it's just the averages of all the low tides throughout the year that's all that it is it's just the averages or the mean for all the low tides throughout the year so that's what they choose to be zero so therefore we can have negative tides look at negative 1.1 all right so if we look at this we've got a nice tidal pattern we can see that there is a high tide here's a low right here's a mid low here's a high high here's a low low here's another mid high that's a full tidal pattern then we're back to exactly where we were here okay so these are mixed tides okay now if we look at this graph this is to check your understanding this is a tie graph from alaska so let's see if you can figure out the difference here okay between a b and c okay so let's start with c the title range is smaller than that of san diego okay the title range means how high or how low the range is so if you look on the y-axis we've got 0 9 and 19. this is in feet by the way and we could see okay well it actually does get up to nineteen and zero feet if we look back at the san diego calendar all we see is zero three and six so that's actually much less right title change difference here in san diego is the largest we're going to get is like seven or eight feet so we could have a highest high of about seven and the lowest low about negative one negative two so maybe nine feet total that'd be the largest title title range we got if we look here in alaska we've got something that can go up 19 and go down below zero well below zero negative 3.9 so we're talking up to 25 maybe even 30 feet alright so see the title range is smaller than that of san diego that is false right because we're doing much bigger tidal ranges look at a the type of tide is semi-diurnal well semi-diurnal means that there are two highs and two lows per day and that the highs are the same height and the lows are the same lows so if we look here let's look at the highs and highs well here's one high tide and we move along we get a low tide and then back to high tide if i look at these these are not the same same with the low tides here's a low tide here's a low tide these are not the same either so therefore they're very different so that doesn't that doesn't work out semi-diurnal doesn't work out let's look at b new or full moon meaning okay that's when the moon the earth and the sun are lined up that's when we have our largest tidal ranges our spring tides right likely occurs on the 10th well let's look at the sixth sixth everything seems to be pretty mellow okay the tides are getting more and more extreme if we start looking here right a higher tide is at 17.2 and our low is at negative two that's like 19 feet if we look here at the six it was only about 14 feet okay from the high to the low and looking at this 15.3 and 1.1 and subtracting here i've got 19 feet because i got a negative 2 so i'm adding that in i look to the ninth 18.2 and negative 3.2 oh man now i'm at 21.4 feet and then if i look over here on the 10th wow it's getting even bigger now we're at 19 feet and 4 feet that's 23 feet difference pretty much right here so i would say that b new or full moon that sounds most likely the case because we have the largest title ranges when it's new or full moon exactly right when the earth the moon and the sun are all lined up so b would be my answer could you do that let's try another one all right so if a point on the coast experiences a semi-diurnal tide what does the daily type record show semi-diurnal what does semi-diurnal mean we just talked about it i'm going to give you a second to take a look at this all right let's look at a together process of elimination right one high tide and one low tide per day that's not what semi-darinal means that is a diurnal type right like we have in the gulf of mexico that's not what's happening here that we're looking for a semi-diurnal type all right b one high tide half a tide okay one day and one low tide the next we that's not even one of the title patterns that we've talked about so no a and b are gone now we're just between c d and e okay c either one or two high tides each day as long as they don't change much okay once again this is not talking about any of the title patterns that i've told you exist on planet earth so that's out of its mind we're not that's not we're not going to consider that so c is gone now between d and e so we got a 50 50 shot now right d two nearly equal high tides and two nearly equal low tides each day ooh that does sound right so semi-diurnal tide that sounds like it like that's that's what we're talking about diurnal is just one high and one low and that was a so we know that's not the case and we're looking good here on d and then mixed right let's look at e two unequal high tides and two unequal low tides each day that's for mixed tides so d two nearly equal high tides into nearly equal low tides each day is what semi-journal means perfect we got it take a look back at those slides rewind this video go back to it watch it all over again and try and get that totally settled in your mind okay so i'll be asking more questions coming up soon all right so now you can see right once again we got mixed tides and purple all along this entire realm that we live right here in california we've got semidurnal tides here on the east coast of the u.s and then within the gulf of mexico we've got some blue spot uh some yeah blue spots which are diurnal tides so there you go there's your diurnal tides okay