21 - Drought Flashcards
what is drought
period of drier than normal conditions - can last for days, months or years
what is mega drought
drought lasting 2 decades or more
what is evapotranspiration
transpiration + evaporation
what is the process of transpiration
veg sucks moisture up from ground, and releases vapour through stomata in leaves
what is dry
when evapotranspiration > precipitation
where do droughts generally occur
already arid subtropics but will extend further with global warming
how are rainforests at risk
risk of undergo feedbacks towards a near irreversible savannah/desert state
how much of earths evapotranspiration is transpiration
70%
how does deforestation dry out soils
allows ground level temperature and wind speeds to increase, increasing evaporation, which dries out soils, causing more deforestation
what impacts does drought have
has critical environmental impacts which can then cause impacts for society and economy
what are ways to stop drought
- reduce global warming
- stop deforestation
- regretting decertified areas
what does regretting do
cools the ground, preserves what precipitation occurs, refertilises the soil and improves soil water retention
