GEO Precipitation in Extreme Environments Flashcards
Why are deserts dry?
Deserts are dry because of the direction of the wind. In the Sahara desert, the wind has blown over hot land so the winds are hot and dry
What are rainshadows?
Rainshadows are when rain falls over mountains before reaching the desert
Where do deserts lie?
Deserts lie at the tropics. Tropic of Cancer and Tropic of Capricorn
Why is there no rain in deserts?
There is no rain because cold air is sinking and warming. There is no moisture so there are no clouds, and therefore no rain
Why are polar regions dry?
Polar regions are dry because the air pressure is high, which means that cold air is sinking.
Why are there very little precipitation in polar regions?
Cold air is sinking, this means there is no condensation and no clouds and therefore very little precipitation
Why are polar regions cold?
It is cold because of the direction of the wind. In Antarctica, the cold Katabatic winds blow down from the mountains, so the winds are cool and dry.
What are katabatic winds?
Katabatic winds are strong winds that blow downhill
Why are rainforests wet?
It rains daily because rainforests are located where warm air is rising. The intense heat from the sun heats the land in the morning, and in turn the air next to the ground is heated and warm air rises upwards.
Why is the air moist in rainforests?
The air is moist due to evaporation, from the rivers, swamps, and vegetation. This water vapour makes conditions very humid.
Why are there heavy rainfalls in the afternoon (TRF) ?
Because air cools as it gets higher in the atmosphere, and Cumulonimbus clouds form as the water vapour cools and condenses. We then get Convectional Rainfall.
Explain how TRFs help control the earth’s climate
Tropical rainforests control the earth’s climate by absorbing carbon dioxide from the atmosphere. When deforestation happens carbon dioxide is let out into the atmosphere again, which contributes to greenhouse gases. When it is burned, the same thing happens and all the carbon dioxide in the wood and leaves are let out. Tropical rainforests are factors that are needed to keep the human race alive.
What percentage of greenhouse gas emissions come from TRF deforestation?
20%
