Weather Hazards and Climate Change - Drought

Question 1

What are arid environments?

Answer 1

1. Places which normally have very low rainfall
2. Many arid environments are very hot causing water to evaporate faster than it can be replaced

Question 2

Characteristics of arid environments?

Answer 2

1. Sparse plant growth -> lack of rainfall
2. Hardly any leaf fall -> shallow and infertile soils
3. Soil often dry and dusty

Question 3

What is a drought?

Answer 3

1. A drought is a severe shortage of water in a particular location
2. Water supplies become depleted during a drought because people keep using them but they aren’t replenished
3. Often high temperatures -> increases rate of evaporation and demand for water

Question 4

How can droughts be hazardous?

Answer 4

1. Depletion of water supplies -> shortages of water in surface water stores ->aquatic plants/animals die
2. Lakes and reservoirs become stagnant -> less fresh water to dilute waste materials -> increased risk of contamination and disease
3. Reduced irrigation -> food shortages -starvation and malnutrition
4. Plants die and soils dry out -> topsoil removed by erosion - difficult to grow crops when rain comes back
5. Wildfires more likely due to dry vegetation

Question 5

Meteorological causes of drought?

Answer 5

1. Meteorological factors -> less rainfall than average in an area
2. Changes in atmospheric circulation can mean it doesn’t rain as much for long periods of time
3. Changes in atmospheric circulation can cause annual rains to fail e.g. monsoons in India

Question 6

Hydrological causes of drought?

Answer 6

1. Rivers, lakes, reservoirs, aquifers -> part of hydrological system -> lack of water in these stores -> drought
2. Drought more likely in areas that rely on rainfall and surface water stores -> in warm, dry conditions these stores evaporate quickly so they are depleted quickly
3. These factors can take a while to have an effect but they often have long lasting impacts

Question 7

Human causes of drought?

Answer 7

1. Intensive farming -> irrigation depletes water supplies
2. Farming livestock require lots of water to drink
3. Building dams reduces the flow of water downstream -> causes drought in other ares
4. Deforestation reduces amount of water held in soil -> land dries out more quickly
5. Trees release lots of moisture into the air -> deforestation makes atmosphere drier -> meteorological cause of drought

Question 8

What can the pattern of drought be explained by?

Answer 8

1. The pattern of droughts can be explained by global atmospheric circulation
2. Cool, dry air sinks at 30° north and south of the equator -> creates a belt of high pressure and low rainfall

Question 9

Ethiopia drought background?

Answer 9

1. Ethiopia is a developing country in the Horn of Africa.
2. In 2016, south Ethiopia was hit by one of the most intense droughts for over 30 years
3. The drought was caused by a change in the pattern of global atmospheric circulation -> region was hotter and drier than normal

Question 10

Ethiopia drought impacts on people?

Answer 10

1. 85% of people in Ethiopia depend on agriculture as their main live livelihood -> without rain, crops did not grow -> farmers lost 50-90% of crops in some regions
2. Lack of pasture for livestock -> milk production slowed down - by 2017 up to 2 million animals had died
3. Many people lost jobs in farming -> had to move to cities to find work
4. Lack of food and employment - widespread food insecurity and malnutrition - 70,000 at risk of starvation - in 2017 - 7.8 million people needed emergency assistance to meet basic food needs

Question 11

Ethiopia drought impacts on ecosystems?

Answer 11

1. Water sources dried up - plants died - less food at water available for wildlife
2. Loss of vegetation damaged important habitats - threatening endangered species
3. Areas vulnerable to wildfires and desertification

Question 12

Government response to Ethiopia drought?

Answer 12

1. Distributed food from its national food reserve through productive safety net program
2. Provided people with permanent housing near sources of water

Question 13

Individuals response to Ethiopia drought?

Answer 13

1. People migrated away in search for new livelihoods or to work on the productive safety net program
2. Farmers in some areas switched from growing cereal crops to a more resilient crop called chat

Question 14

Organisations response to Ethiopia drought?

Answer 14

1. Charities/international organisations provided humanitarian aid - fund emergency food, water, medicine
2. The FAO of UN requested $20m for programmes - distributing seeds and preventing pests in crops
3. FAO helped treat livestock that became ill and co-ordinated respondes to make sure help reached people in the worst affected areas

Question 15

Australia drought background?

Answer 15

Australia hit by the “Millennium Drought” in the early 21st century

Question 16

Australia drought impact on people?

Answer 16

1. Water levels in lakes and rivers fell, so water supplies ran low
2. Crop yields fell - crops that rely on irrigation badly affected - rice production fell to 2% of pre-drought totals
3. Increased food prices- Livestock died - number of sheep in Australia fell by 8 million during 2002-03
4. Farmers income fell - over 100,000 lost ther jobs
5. Over 30,000km of land burned from forest fires - 8 people were killed

Question 17

Australia drought impact on ecosystems?

Answer 17

1. Vegetation loss - soil erosion - rivers and lakes suffered from toxic algae outbreaks
2. Rivers, marshlands dried up - water temperatures rose - plants and animals died
3. Wildfires destroyed and damaged habitats

Question 18

Government response to Australia drought?

Answer 18

1. Water conservation measures introduced - 3 million people who rely on the river murray - allocation reduced
2. Cities built desalination plants - turn sea water into drinking water
3. Provided more than 23,000 rural families - 1500 small businesses with income support - help them survive
4. Invested in improving forecasting to help farmers prepare for drought

Question 19

Individuals response to Australia drought?

Answer 19

1. People started using water saving measures - re-using grey water - water efficient showers
2. Farmers used techniques like drip irrigation to reduce water loss
3. People diversified their incomes

Question 20

Organisations response to Australia drought?

Answer 20

1. Schools and media organisations ran campaigns - encouraged people to reduce water use
2. CSIRO teamed up with businesses to breed new drought toleranta varieties of wheat