Dry Droughts
Dry and Deadly
How droughts form
Droughts occur when a region receives consistently below average precipitation. It can have a substantial impact on the ecosystem and agriculture of the affected region.
Brazilian drought
Instead of rain, São Paulo has cracked earth and chaos as a devastating drought is making enemies out of neighbors in Brazil’s largest city, the site of a historic water shortage the likes of which hasn’t been seen in decades. Many residents have gone to drastic measures to hoard the precious commodity in the face of tougher water use restrictions, pinched faucets and declining reservoirs. Local authorities fearing anarchy in the city of 11 million are considering bringing in the military to control what’s quickly spiraling into a war over resources.
Australian drought
Australia is the most drought-prone continent on earth with droughts occurring for 82 of the 150 years since reliable record-keeping began in 1860. Despite this, significant gaps exist in our understanding of the effects of these ‘creeping disasters’ on our waterways and in our ability to manage these effects.
Indian drought
Over a period of two centuries (between 1801 and 2002), India experienced 42 severe droughts, according to the Indian Space Research Organisation. One of these, in 1979, cut food grain production by 20 percent; another, in 1987, damaged 58.6 million hectares of cultivated land, affecting 285 million people
Were droughts can happen
Droughts usually form near warm and dry places
Effects
Periods of droughts can have significant environmental, agricultural, health, economic and social consequences. The effect varies according to vulnerability. For example, subsistence farmers are more likely to migrate during drought because they do not have alternative food sources. Areas with populations that depend on water sources as a major food source are more vulnerable to famine.
Drought can also reduce water quality because lower water flows reduce dilution of pollutants and increase contamination of remaining water sources. Common consequences of drought include:
- Diminished crop growth or yield productions and carrying capacity for livestock
- Dust bowls, themselves a sign of erosion, which further erode the landscape
- Dust storms, when drought hits an area suffering from desertification and erosion
- Famine due to lack of water for irrigation
- Habitat damage, affecting both terrestrial and aquatic wildlife
- Hunger, drought provides too little water to support food crops.
- Malnutrition, dehydration and related diseases
- Mass migration, resulting in internal displacement and international refugees
- Reduced electricity production due to reduced water flow through hydroelectric dams
- Shortages of water for industrial users
- Snake migration, which results in snakebites
- Social unrest
- War over natural resources, including water and food
- Wildfires, such as Australian bushfires, are more common during times of drought and even death of people.
- Exposure and oxidation of acid sulfate soils due to falling surface and groundwater levels.