lecture 03 - environmental variations Flashcards
what does climate create in the environment?
variation (physical traits of environment and animal variation in environment)
what are the tropics of cancer and capricorn
the maximum latitudes where the sun are directly overhead (around 23 degrees)
where the tropical rainforest and savannahs are
what is climate
long term average of weather
importance of the sun
vital for ecological processes
warm air = air currents = different ecosystems
what is weather
day to day state of our atmosphere
why is the equator hotter compared to the poles?
energy hits a smaller surface compared to the higher latitudes, the distance between the sun and earth and will be hotter
why are the poles colder than the equator?
energy is scattered across a larger surface compared to the equator, distance between the sun and earth is longer and will be colder
what causes global air circulation?
the uneven distribution of solar energy per unit area across latitude acts like a motor that sustains major air circulations on our planet
what are the 3 atmospheric circulation cells
hadley cell, ferrel cell, polar cell
how are hadley cells formed?
warm air rising, cooling and forming condensation at the equator
what happens to the cells at 30 degree latitude
airmasses descend, warm up and absorb moisture which cause heavy rainfall. cool air then falls back down with dry air and absorbs moisture from the environment which creates desert
how are ferrell cells formed?
they are not maintained by cooling or warming effects, but rather by the strong energy of the other cells (pulling them in both N and S
how are polar cells formed?
form due to warming and cooling of air. airmasses rise to 60 degrees and cool down closer to the poles, where they descend as very cold air
what is the coriolis effect?
winds that flow from the poles in different directions and deflections
where do the trade winds come from?
from hadley cells and come from the NE and SE
where do the westerlies winds come from?
from ferrel cells
what are the westerlies winds?
air pushed down from the west that suck up moisture
where do the polar easterlies winds come from?
from polar cells that come from the east
what does topographic mean?
arrangements of the physical features of an area
what are gyres
circulation systems created by horizontal surface currents across the ocean, driven by winds, the coriolis effect and land masses, gyres also exchange water, energy, salts and nutrients
what are coastal upwellings?
wind-driven off-shore movement of water
