Drought

Countries affected: Niger, Mali, Sudan, Chad and Burkina Faso. 10-20 million people were affected.

The drought:

• made the landscape very bare and arid
• made it so crops couldn't grow in the try land - made worse by there being a bad harvest that year - lack of crops also meant livestock starved
• shortage of food led to malnutrition - children are most at risk of sickness and weakness because of this
• food prices increase because of increased demand and decreased supply - affected poor people the most

The Red Cross and The Red Crescent provided aid but it could not come sooner as people waiting until the last minute when people were dying and desperate to donte. Rain may not help the drought as it might not come quick enough or there might not be enough - it can also block roads and access to aid. Drought resistant seeds are a solution as they require less moisture to grow.

The Sahel region is South of the Sahara Desert and contains countries like Ethiopia, South Sudan and Burkina Faso. It is between the Tropic of Cancer and the Equator (south of the Tropic of Cancer and north of the Equator)

Drought may be made worse in the Sahel by the process of desertification. This process is:

• Livestock such as sheep, cattle and goats are left to graze on the grass
• The grass is eaten before it has chance to reach its full height
• This means the roots are small and are therefore unable to anchor the soil
• Soil is also exposed when the grass is grazed close to the ground
• The soil is more easily eroded by wind and water which leads to desertification
• The cycle then continues

Reversal of the normal winter ocean currents in the Pacific Ocean - happens every 11 years or so

10 steps of El Nino:

• The ocean current reverses so there is cold water in the west by Australia
• Warmer water in the east by the coast of South America
• Trade winds blow east over the Pacific Ocean and pick up moisture
• Air rises over the South American coast
• Air cools and condenses
• This forms rainclouds over South American
• Heavy rain and thunderstorms occur on the South American coast
• Trade winds blow back over the Pacific Ocean, travelling west and losing moisture
• Air descends over the Australian coast
• Droughts occur in Australia

Rainclouds don't form in high air pressure because the air is pushing down and it doesn't rise, cool and condense which is necessary for raincloud formation

Key words:

• Drought = a period of time when an area is without water so there is not enough of it to support crops or people
• Arid = land that is without water or moisture and therefore is extremely dry
• Precipitation = water falling from the sky eg. rain, hail, snow, sleet, etc.
• Evaporation = the process where water changes from liquid to water vapour
• Transpiration = liquid water being put back into the atmosphere as water vapour
• Effective precipitation = the difference between precipitation and evapotranspiration

Drought occurs when there is less precipiation than there is evapotranspiration over a period of time. This is known as negative evapotranspiration.

Rainwater storage tanks:

• stores water and prevents evaporation which ensures the water supply lasts long into the future
• for everyone as local communities have access to clean, safe water
• people don't have to travel long distances for a long time to collect water
• free water source
• cost effective as it is cheap and simple to build and maintain

Groundwater supply pump:

• everyone has access to clean and safe water
• it's cheap and simple for the community to maintain
• no long distance travel to collect water
• small scale so it isn't as harmful to the environment