Unit 10: Climate Classification
Tropical/sub-tropical moist climates (A Climates)
-All have monthly ave. temperature above 18C (64F) -Af= Tropical wet, rainforest *consistently moist because of Hadley cells and sub solar point *further from equator= more seasonality -Aw= Tropical wet and dry, savanna *summer wet, winter dry *Transition zone between forests and grasslands -Am= Tropical Monsoon, monsoon Forests *India
What is the main climatic control that makes Mediterranean climates have a more pronounced summer dry period?
-Almost no rain in summer -cold ocean currents bring dry air
Arid Sub-Climates (B Climates)
-Bw= Dry arid, true desert *Bwh= low latitudes *Bwk= mid latitudes -Bs= Dry semi-arid, steppes
What factors contribute to arid climates?
-Centralized in West near Tropic of Cancer -potential evapotranspiration exceeds precipitation; barren -consistent high pressure + continentality makes area very dry -Highest variability in precipitation -Descending air of Hadley Cells -Driest towards West because of Easterlies -e.g., Calahari, Sahara, interior of Asia
Class C sub-climates
-Cf (Marine)= Perpetually moist temperate climates *Cfa= humid subtropical *Marine Climates: Cfb=mild winter Cfc=cold winter -Cs (Mediterranean)= Summer Dry; -Cw= Winter Dry
What factors lead to dry climates?
-Descending air/Proximity to Hadley Cells -Continentality -Easterlies
Class D sub-climates
-Df= no dry season -Dw= winter-dry, continental
Polar/Arctic subcategories
-Et= Polar tundra -Ef= Polar Ice cap, eternal frost *below freezing all year *no vegetation
Mild Mid-Latitudes with Moderate Temperatures (C Climates)
-known for variation -In close proximity to coast -summer temps are warm to hot and winters are mild -coldest month ave. temp 18C (64F)- -3C (27F) -East+West Coast of North America, China, Japan
Highland Climates (H Climates)
-severely affected by altitude -different from places of similar altitudes at lower elevations
Major Severe Midlatitude/ Humid Continental Climates (D Climates)
-stable cold air over long period of time -cold and dry bc severe continentality -situated further from coast= affected by easterlies -summers warm, winters cold -average temp. of warm months is greater than or equal to 10C (50F) -ave. temp. of cold months is less than or equal to -3C (27F)
Polar/Arctic Climates (E Climates)
-very cold winters with virtually no summer season -highest ave. temperature of warmest month= below 10C (50F)
Westerlies
Dominant winds of the mid-latitudes. These winds move from the subtropical highs to the subpolar lows from west to east.
Tundra
Frozen soil
Easterlies
Global winds that flow from the east to the west;Winds between North pole and 60 degrees
sub solar point
Point on the planet where the sun's rays are exactly perpendicular to the surface *oscillates between tropics *corresponds to equinoxes and solstices
Pros and Cons of climate classification systems
Pros: simplifies our examination of climate, so we can group things together that are similar and make general understanding fairly rapidly. Cons: human construct; simplification of a much richer reality; different ways you could classify things.
Continentality
The effect of distance from the moderating influence of the sea on climate
Hadley Cells
a large-scale atmospheric convection cell in which air rises at the equator and sinks at medium latitudes, typically about 30° north or south. *transfers heat from equator towards poles
What happens if potential evapotranspiration exceeds precipitation?
hard to grow plants
Potential Evapotranspiration
how much water COULD be evaporated if available
Transpiration
regards water evaporated/released from plants
Climograph
tool used to track various patterns (such as temperature and precipitation) over months
What's the difference between weather and climate?
weather tracks short term present day phenomena whereas climate tracks the phenomena ina region over decades.
What effects climate?
wind patterns, water currents, and geography/ topography, continentality, temperature, precipitation
Hundredth Meridian
Area that runs through the middle of the Great Plains, where rain isn't as plentiful; separates two major climates in US