EQ1 the global hydrological cycle statistics Flashcards Preview

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Flashcards in EQ1 the global hydrological cycle statistics Deck (10)
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1

what percentage of water on earth occurs as fresh water?

2.5%

2

what percentage of this fresh water is accessible and where is the majority of the worlds fresh water located??

1% accessible
2/3 rds of world's freshwater is locked up in the cryosphere

3

TROPICAL RAINFORESTS HYDROLOGY
what % of precip. is consumed by dense vegetation and how much is l returned by evapotrans. ?

75% of precipitation
50-75% is returned by evapotrans.

4

TROPICAL RAINFOREST HYDROLOGY
annual precipitation is how much?

2000 mm

5

POLAR HYDROLOGY
what is the annual precipitation?

less than 200 mm

6

where is most of the world's water located and how much?

96.5% in the oceans

7

what % of water is in the ice caps?

nearly 2%

8

what water store has the longest residence time?

groundwater - 10,000 years
ice cap- 15,000 years depending on size

9

DEFORESTATION IN AMAZON FOREST
Effects of deforestation in Amazon basin?

- Reduction of nearly around 324km^3 of river runoff by deforestation & human regulation of river flow
- reduction of vegetation = increased surface run off and less infiltration = higher river levels after rainfall
- drop in green water stores and increase in blue water stores
- conventional and frontal rainfall/ precipitation recycling is not able to occur due to decrease in evapotranspiration

10

WATER ABSTRACTION IN THE ARAL SEA
What happened to the Aral Sea?

- Diversion of rivers that fed it = shrinking of sea by 10% in 1999 - splitting it into 4 lakes for Soviet irrigation projects
- By 2014 most of Aral Sea had dried up only the eastern basin remains