Chapter #4 - Weather & Climate
Weather vs. Climate
- Solar Energy/Insolation
- Axis Inclination
- Energy Budget
- Environmental Lapse Rate
Air Pressure & Wind
Stages of Development
- The first stage of air mass thunderstorm
development is called the cumulus stage (picture).
- The second stage begins when the updrafts
reach their maximum altitude in the developing cloud, usually 12 to 14
kilometers. The updrafts change their direction 180° and become
downdrafts. This marks the mature stage (picture).
With the downdrafts, precipitation begins to form through collision
and coalescence (picture).
The storm is also at its most intense stage of development and is now
a cumulonimbus cloud The top of the cloud takes on the familiar
anvil shape, as strong stratospheric upper-level winds spread ice
crystals in the top of the cloud horizontally. At its base, the
thunderstorm is several kilometers in diameter. The mature air mass
thunderstorm contains heavy rain, thunder, lightning, and produces
wind gusts at the surface.
Average number of days with thunderstorms
- Lightning (image)
- Tornadoes (air
photo: tornado path)
Climate Soils & Vegetation
- Soil Formation - contains
organic and inorganic material.
How soil is made
- geologic factor - influences
the depth, texture, drainage and nutrient content of a soil.
- climate factor - temperature
and precipitation effects on soil.
- temperature affects:
- length of growing season
- speed of vegetation decay
- rate of evaporation
- precipitation affects:
- type of vegetation that grows
- supply of humus
- topographic factors:
- height of land
- slope aspect
- slope angle
- topographic factors affect:
- cloud cover
- surface runoff of water
- rates of erosion
- biologic factor - living and
dead plants and animals
- chronological factor: length
of time the preceding four factors have been interacting.
- Soil Profiles & Horizons -
soils develop layers that differ in their structure, texture, color.
- O-horizon: fresh, decaying
- A-horizon: fertile,
maximum nutrients, biologic activity and humus. Dark color.
- E-layer: eluviation
(outwashing) layer results from water percolating and removing some of the
organic and mineral matter. Lighter color.
- B-horizon: zone of
illuviation (inwashing). Less organic material than A-horizon.
- C-horizon: where weathering is
slowly transforming bedrock into soil particles.
- R-horizon: unaltered
Soil profile graphic
showing effects of slope
Generalized soil profiles found
in five major ecosystems
- Soil Properties: minerals,
organic matter, water and air interact to produce distinctive soils.
- texture: size of mineral
matter and is determined by proportions of sand, silt and
clay. The best agricultural soils are called loams and consist of
about 40% sand, 40% silt and 20% clay. (Loam
- structure: texture influences
soil structure, the way particles aggregate into larger clumps. The size and
shape of clumps affect the capacity of soil to hold water, air
Soil Classification Map
Natural Vegetation & Climate
- Koppen Climate Classification
- Tropical Wet (Af) Climates
- Arid & Semi-Arid (BW, BS) Climates
- Mid-Latitude C Climates
- D Climates