Drought

Picture 1: Drought Picture 2: Drought Picture 3: Drought

A drought is a long phase of months or even years when a region remarks an insufficiency in its water supply. In general, this occurs when a region receives continually lower standard precipitation. The agriculture and the ecosystem of the affected area can suffer substantial impacts because of droughts. The damages of a drought, even a short drought can be devastating in the local and in the economy. This phenomenon has a wide impact on agriculture. ‘The United Nations estimates that an area of fertile soil the size of Ukraine is lost every year because of drought, deforestation and climate instability’.

- Causes

- High pressure systems;
- Winds carrying continental;
- Oceanic air masses;
- High pressure areas;
- Oceanic and atmospheric weather cycles (El Niño-Southern Oscillation);
- Deforestation;
- Erosion;
- Climate change.

- Consequences

- Diminished crop growth or yield production and carrying capacity for livestock;
- Wildfires;
- Shortages of water for industrial users;
- Dust storms;
- Malnutrition, dehydration and related diseases;
- Famine (because of the lack of water for irrigation);
- Social unrest;
- Mass migration, resulting in internal displacement and international refugees;
- War over natural resources, including water and food;
- Reduced electricity production due;
- Reduced water flow because of hydroelectric dams;
- Snakes migration and increases in snakebites;
- Erosion of landscape;
- Damages of terrestrial and aquatic habitat.

- Stages of drought

- Meteorological: when there is a prolonged period with less than average precipitation. This kind of drought usually precedes the other kinds of drought.

- Agricultural: affects crop production or the ecology of the range. This condition can also arise independently from any chance in precipitation levels when soil conditions and erosion provoked by a bad planned agricultural endeavors cause a shortfall in water available to the crops. However, in a traditional drought, it is caused by an extended period of below average precipitation.

- Hydrological: when the water reserves available in sources like aquifers, lakes and reservoirs falls below the statistical average.

- How to prevent?

- Desalination of sea water;
- Drought monitoring;
- Land use (carefully planned to help minimize erosion);
- Rainwater harvesting;
- Recycle water;
- Irrigation in drought-prone areas;
- Water restrictions;
- Cloud seeding;

Source: http://en.wikipedia.org/wiki/Drought#Drought_mitigation_strategies

http://keetsa.com/blog/wp-content/uploads/2007/06/drought.jpg

http://www.naringalchurch.org/images/Drought%20branch.jpg

http://www.rcdnet.org/Documents/Drought/Drought%20Pix.jpg

Carolina