Water Cycle eq2

Question 1

define drought

Answer 1

extended period of deficient rainfall relative to the statistical average for a region measured iver a very long period of time

Question 2

What are the causes of drought?

Answer 2

1. dams
2. deforestation
3. ENSO cycles
4. changes in precipitation patterns
5. irrigation (65%)

Question 3

4 types of drought

Answer 3

1. agricultural drought
2. socioeconomic drought
3. hydrological drought
4. meteorlogical drought

Question 4

what makes an area more vulnerable?

Answer 4

• if they are directly dependant on the land
• poverty
• lack of preparedness

Question 5

What are the economic impacts of drought?

Answer 5

• reduced water levles
• decreased agricultural productivity

Question 6

What are the environmental impacts of drought?

Answer 6

• fire hazard
• soil erosion

Question 7

What are the social impacts of drought?

Answer 7

food shortages

Question 8

4 key causes of meterorlogical drought

Answer 8

1. natural variations in the atmosphere
2. El Nino events
3. Changing land use
4. Climate change creating regional and local effects

Question 9

3 atmospheric circulation cells

Answer 9

• polar
• ferrel
• hadley

Question 10

intertropical covergence zone

Answer 10

Sometimes the subtropical high pressure zones, associated with the descending parts of the convection cell (Hadley cell) block the high humidity, rain bearing air masses associated with the ITC2, so that the pattern is modified

Question 11

mid-latitudes blocking anticyclones

meterological drought

Answer 11

• low air pressure affected by jett streams
• high pressure areas from tropics move northwards
• stable weather conditions with little precipitation
• block weather systems for up to 2 weeks
• normal precipitation greatly reduced

Question 12

normal conditions in the pacific

Answer 12

• warm water
• Australia
• low pressure
• risk of flooding
• cold water
• south america
• high pressure
• risk of drought

Question 13

El Nino conditions in the pacific

Answer 13

• warm water
• south america
• low pressure
• risk of flooding
• cold water
• australia
• high pressure
• risk of drought

Question 14

El Nina conditions in the pacific

Answer 14

• warm water
• Australia
• low pressure
• risk of flooding
• cold water
• south america
• high pressure
• risk of drought

(enhanced normal conditions)

Question 15

direct human causes of drought

Answer 15

taking water direclt from a store (abstractation)

Question 16

indirect human causes of drought

Answer 16

altering hydrological processes (deforestation)

Question 17

Brazil

Answer 17

• over abstractation of surface-water resources and groundwater aquifers
• drought particularly affected Sao Paulo as groundwater ran low
• people began to drill illegal wels due to high fees
• drought caused stress to amazon

Question 18

The Sahel, Africa

Answer 18

• droughts of the 20th century were cased by air pollution which caused atmospheric cooling
• could have been casued by higher sea level by anthropogenic climate change
• dry areas being converted into farmland to feed high population

Question 19

what are wetlands?

Answer 19

areas of land which is saturated with water either permenantly or seasonallt eg swamps, bogs and fens

Question 20

what are forests?

Answer 20

dense community of trees, highly valuable for goods and services eg carbon sequestation and food

Question 21

droughts impact on wetlands

Answer 21

water supply reduces, leads to habitiat loss

Soil moisture reduced, leads to soil erosion and reduced ability to store water

Question 22

droughts impact on forests

Answer 22

die back of species, regulation of climate change due to carbon sequestation, pine bark beetles attack trees

Question 23

droughts impact on animals in wetlands

Answer 23

birds and bugs show varying responses, can eliminate species, disrupt food webs

Question 24

droughts impact on forest animals

Answer 24

forest fires can lead to death of species eg nearly 3 billion animals habve dies or been dispalced

Question 25

4 types of flooding

Answer 25

1. monsoons 2. prolonged rainfall 3. flash flooding 4. snowmelt

Question 26

monsoons

Answer 26

Occurs across Southeast Asia between May and September. Larger than normal low-pressure systems. The monsoon climate results in high annual rainfall totals exceeding 1.5 m (5 ft) in many places

Question 27

prolonged rainfall

Answer 27

* ground has become saturated from prolonged heavy rainfall * leads to more water entering the river channel, increasing the likelihood of flooding. * Days of intense and prolonged rainfall are likely to increase with global warming. * The 2014 Somerset floods resulted from 350mm of rainfall in one month.

Question 28

flash flooding

Answer 28

* A flood with an exceptionally short lag time - often minutes or hours * Flash floods can carry large debris such as boulders. This combination can cause heavy structural damage to homes making them uninhabitable and can carry away large pieces of property such as vehicles. * Boscastle floods in 2004 - The village of Boscastle in Cornwall experienced flash flooding on 16 August 2004 when an exceptional amount of rain fell over eight hours.

Question 29

snowmelt

Answer 29

* A type of glacial outburst flood that occurs when the dam containing a glacial lake fails. * Rapid snowmelt can trigger landslides and debris flows. * Increased water runoff due to snowmelt was a cause of many famous floods. One well-known example is the Red River Flood of 1997, when the Red River of the North in the Red River Valley of the United States and Canada flooded.

Question 30

urbanisation | anthropogenic causes of flooding

Answer 30

- impermeable surfacees decrease infiltration rates - increase surface runoff into rivers - shortens lag time as water is directed at river - eg by bridges

Question 31

deforestation | anthropogenic causes of flooding

Answer 31

- reduces interception and evapotranspiration - increases surface runoff - exposes soil to erosion - increases river sediment load and deposition - reduces rivers capacity to hold water - eg Tibet deforestation caused flooding in Bangladesh

Question 32

floodplain drainage | anthropogenic causes of flooding

Answer 32

- provides agricultural areas in developed countries - reduces natural capacity of floodplain - land shrinks as it dries out - more susceptible to flooding

Question 33

flooding mis-management | anthropogenic causes of flooding

Answer 33

- alterations at one point of a drainage basin can cause consequences downstream - hard engineering designed to reduce frequency of floods eg channel straightening and embacnkments

Question 34

India

Answer 34

- seasonal monsoons are vital for half the populatio who work in agriculture - major 2017 flood event caused 1200 deaths - long term vulnerability increasedd

Question 35

japan

Answer 35

- 5m deep floods in area already recovering from earthquake - 225 deaths from landslides - trains cancelled left people stranded

Question 36

general impacts of flooding

Answer 36

- lack of productivity - displacemement of people - loss of life - spread of waterborn diseases - strain on emergency servicfes - homelessness - transportation cancelled - damaged infrastructure

Question 37

UKs climate change by 2050

Answer 37

- wetter winters due to low pressure - dryer summers - high water levels due to thermal expansion and melting glaciets

Question 38

snow | UKs climate change by 2050

Answer 38

reduce

Question 39

river flow | UKs climate change by 2050

Answer 39

high and flooding

Question 40

climate models predict tht climate change could cause

Answer 40

- precipitation to become more variable - increased risks of droughts and floods - create uncertain water supply