• different organisms have different cellular tolerances for cold and heat
• organism classification based on temperature source and regulation:
  • ectotherm - obtains heat primarily from the environment
  • endotherm - obtains heat primarily from metabolic reactions
  • poikilotherm - temperature regulated primarily by environment
  • homeotherm - temperature regulated primarily by internal homeostatic mechanisms
• contributes to erosion & creation of soil

• challenge of water balance in terrestrial and freshwater environments
• animals that have secondarily returned to marine environments face osmotic challenges, as the ocean is now saltier than when their ancestors left it.
• important component in erosion & creation of soils

• intensity
• daily duration
• angle of incidence of the sun (seasonal changes)
• competition for light is an important selective factor in many environments, and this has driven selection of many species
• photosynthesis wavelengths primarily in the blue & red regions of spectrum; understory and underwater regions have varying levels of these wavelengths, with red light being lost first, and blue light last.
• photoperiodicity can be diurnal, seasonal, etc. (Circadian rhythms)

• contributes to erosion
• affects perceived temperature via evaporation & convection
• affects desiccation rate
• affects growth form of plants

• topography creates habitat
• mineral (inorganic nutrient) content of rock affects flora
• pH of rock/soil affects flora
• substrate composition affects any water in contact with that substrate

• Here's a nice overview of how SOIL comes to be...

• fire
• severe storms (hurricanes, tornadoes, etc.)
• volcanic activity
• oh, heck. Comets, too.

GLOBAL PATTERNS OF CLIMATE

The ultimate source of climate is the sun, which provides not only the majority of energy on earth, but also creates climatic events when its randomizing energy interacts with the earth.

• the TROPICS lie between the Tropic of Cancer (23.5^o N) and the Tropic of Capricorn (23.5^o S). These receive the highest annual input of solar energy, and are the only place on earth that the sun ever shines directly overhead (on the equinoxes, March 21 and September 21).

• the SUBTROPICS lie between the Tropic of Cancer and 30^oN in the northern hemisphere, and between the Tropic of Capricorn and 30^oS in the southern hemisphere. (Miami is in the subtropics)

• the TEMPERATE regions lie between 30^oN and 60^oN in the Northern Hemisphere and between 30^oS and 60^oS in the Southern Hemisphere.

• the POLAR REGIONS lie above 60^oN and S

Flora and fauna are profoundly affected by environmental and seasonal changes in solar intensity and spectral distribution. Note also that because the sun is tilted 23.5^o on its axis (defining those tropical latitudes), there are seasonal changes solar irradiation in both hemispheres:

Solar warming of earth creates

• Warm, high levels of precipitation: Tropics
• Relatively warm, arid: subtropics and temperate regions
• Cool, high levels of precipitation: just below polar area; coniferous forests dominate
• Cold, arid: polar regions (Arctic and Antarctic)

Climate can be affected locally by

This creates smaller, localized ecosystems within large, ecologically distinct areas known as biomes.

Climate is the primary factor that determines what organisms can live in any given habitat. Therefore, climate is what causes certain areas of the earth to become distinctive BIOMES.