Precipitation and Climate Regions

All forms of water that fall from the atmosphere

Convectional PrecipitationLighter, warmer air absorbs more moistureWhen the air cools, excess water is released,

forming cloudsWhen clouds become “full,” water is released

(rain, snow, sleet, or hail)Common in the tropics

Precipitation

Precipitation comes down and finds its way down to the lowest point through Ground run-off rivers and streamsSubsurface run-off

Back into the atmosphere throughEvaporation (liquid into gas) from bodies of

waterTranspiration – evaporation from plants

Hydrologic Cycle

Orographic – warm air is forced upwards by mountainsReleases moisture on windward side of the

mountain. The leeward side (away from the wind) is in a rain shadow.

Frontal – two air masses, or fronts, collide. The colder one forces the warmer one up higher.

2 Other Kinds of Precipitation

Most classification systems use temperature and precipitation as major factors

What influences climate?Distance from water- coastal areas often have a

milder climate than inland areas.Elevation-temperature drops about 3.5 degrees

for every 1000 feet of elevationLandforms-any tall structures can effect

climate, creating micro-climates

World Climate Regions

Tropical- Either Wet or Dry. Hot all year long, up to 100 inches/year in precipitation.

Dry-Arid or SemiaridHot days, cool to cold nights18 inches of pre/year at the most

Climate Regions

Moderate- Mediterranean, Humid Subtropical, Marine West CoastHot summers, cool wintersModerate amounts of precipitation

Continental- Humid or subarcticWarm/cool summers and cold/very cold wintersModerate precipitation

Polar- Tundra or Ice CapDuh, it’s cold.Precipitation- snow. Lots of snow.

Plant Community- natural grouping of plants that can survive successfully in a particular environment

Biome- Environment, plants, and animals are well-suited to one another.

Vegetation Regions

Tropical Rain ForestNear the equatorLarge amounts of rainTall trees form a canopy, or a thick covering of

foliage that blocks out much of the sun. (A “tree-roof”)

Forest Regions

Mid-Latitude ForestTemperate climatesDeciduous trees- shed their leaves during one

seasonConiferous Forest

“Cone-iferous” – cones protect seedsColder areas“Needle” trees – Pine, Spruce, Fir. Thin, long

leaves expose only a small surface to the cold.

ChaparralCalifornia and northern MexicoSmall evergreens and low bushes (“scrub”)Found in other Mediterranean climates under

different names

Tropical – SavannasSome trees; far enough apart to prevent a

canopy.Constant sunlight Plants can survive the dry seasons

Temperate- PrairiesTrees grow near rivers and streamsMostly in North America – the Great PlainsFarmlands

Grasslands

Plants that have adapted to almost no moistureSome, like the cactus, store waterSmall leaves – almost no evaporationSeeds that lie dormant for yearsLong roots

Desert Vegetation

High elevations are cool even when sunnyTree-Line: point after which no trees will

growSmall plants grow in sheltered areasPlants must be able to deal with little sun,

short growing season, and permafrost (permanently frozen layer of soil)

Tundra