Climate Classification and Biomes

Introduction

Regional issues, long-term changes, distribution of climates in the US and globally
Goal: Interpret and explain a climate classification chart

Data Used: Temperature and Precipitation Patterns
Earth-Sun Relationships: Latitude Impact
- Average temperature decreases moving towards poles
- Greater temperature spread away from the equator
Other Influences on Climate
- Solar angle, incoming solar radiation
- Specific heat, heat capacity (e.g., proximity to oceans vs. continental interiors)

Moving away from equator: Increased seasonality, higher temperature ranges
Interior continents: Can get very warm or very cold due to lack of moderating ocean influence

Annual Rainfall and Seasonal Patterns
- Some regions have distinct wet/dry seasons
Precipitation Lifting Mechanisms
- ITCZ (Inter-Tropical Convergence Zone): High precipitation
- Orographic Uplift: Windward side wet, leeward side dry
- Continental Interiors: Generally drier due to lack of moisture source
High Precipitation Regions
- Amazon rainforest, Southeastern Asia monsoons
Low Precipitation Regions
- Deserts (Namib, Sahara, Atacama, Outback, Desert Southwest in the US)
Subtropical and Polar Regions: Dominated by high pressure, generally drier

Air masses dominate regional climates
Examples:
- Gulf Coast (MT air masses)
- Desert Southwest (CT air masses)
- Northern regions (CP air masses)

Important to differentiate consistent precipitation vs. seasonal variations (e.g., monsoon climates)

Focus on names of climates, not letter designations
Letters help map climates but real-world understanding is based on climate names (Rainforest, Desert, Mediterranean, etc.)
Climate names relate to biomes and dominant plant life

Named for prevailing climate and dominant vegetation
High correlation between climate and natural vegetation
Examples:
- Tropical Rainforest: Central America, South America, parts of Africa, Southeastern Asia
- Deserts: Atacama, Southwest US, Sahara
- Tundra: Extremely cold, minimal vegetation
- Taiga: Coniferous forest belt
North America Examples
- Southeastern US: MT air mass, similar vegetation (East Texas to Georgia)
- Marine rainforest in Pacific Northwest
- Warm and cool deserts in the Southwest
- Deciduous and coniferous mixed forests in the northern regions

Temperature and Aridity: Key factors in climate classification
Soil Types Related to Climate
- Example: Grassland soils: Rich in organic matter, good for crops
- Arid soils: Low organic matter, high in calcium carbonate

Components
- Line graph: Temperature
- Bar graph: Precipitation
Example: Houston, Texas
- Temperature never drops below freezing
- 50 inches of annual rain
Understanding Houston's climate helps in comparing other climates