Unlike with sudden weather events such as hurricanes, tornadoes, and thunderstorms, it is often difficult to pinpoint when a drought has started or when it has ended. The initial effects of a drought may be difficult to identify right away, so it may take weeks or months to determine that a drought has started.
The end of a drought is hard to identify for the same reason. A drought may last for weeks, months, or even years. Sometimes, drought conditions can exist for a decade or more in a region. The longer a drought lasts, the greater the harmful effects it has on people.
Droughts affect people in a several ways. Access to clean drinking water is essential for all life, and sources of water may dwindle during a drought. Without the presence of water, people must bring in enough water from elsewhere to survive. Water is also needed for crops to grow. When not enough precipitation falls to naturally water crops, they must be watered by irrigation. Irrigation is possible only when there is enough water in nearby rivers, lakes, or streams, or from groundwater.
During a drought, these water sources are diminished and may even dry up, preventing crops from being irrigated and causing them to die off. She started Blue Legacy to raise awareness that we live on a water planet and must take care of it. Cousteau, the granddaughter of the famed ocean explorer Jacques Cousteau, believes that water will be a crucial issue in this century.
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When water from wet soil evaporates, it contributes to the formation of rain clouds, which return the water back to the earth. When land is drier than usual, moisture still evaporates into the atmosphere, but not at a volume adequate to form rain clouds.
The land effectively bakes, removing additional moisture and further exacerbating dry conditions. While drought occurs naturally, human activity—from water use to greenhouse gas emissions—is having a growing impact on their likelihood and intensity.
Climate change—and global warming , specifically—impacts drought in two basic ways : Rising temperatures generally make wet regions wetter and dry regions drier. For wetter regions, warm air absorbs more water, leading to larger rain events. But in more arid regions, warmer temperatures mean water evaporates more quickly.
In addition, climate change alters large-scale atmospheric circulation patterns, which can shift storm tracks off their typical paths. This, in turn, can magnify weather extremes, which is one reason why climate models predict the already parched U. Southwest and the Mediterranean will continue to get drier.
Drought often reflects an imbalance in water supply and demand. Regional population booms and intensive agricultural water use can put a strain on water resources, even tipping the scale enough to make the threat of drought a reality. One study estimates that from to , the human consumption of water increased the frequency of drought in North America by 25 percent. Meanwhile, demand for water supplied by upstream lakes and rivers, particularly in the form of irrigation and hydroelectric dams, can lead to the diminishing or drying out of downstream water sources, which may contribute to drought in other regions.
When trees and plants release moisture into the atmosphere, clouds form and return the moisture to the ground as rain. When forests and vegetation disappear, less water is available to feed the water cycle, making entire regions more vulnerable to drought. As a result, soil dries out faster which can induce agricultural drought , and less groundwater is replenished which can contribute to hydrological drought.
Indeed, experts believe the s Dust Bowl was caused in large part by poor agricultural practices combined with the cooling of the Pacific and the warming of the Atlantic by as little as a few tenths of a degree. The Intergovernmental Panel on Climate Change IPCC did not see a global trend toward increasing dryness or drought across the world in , when it released its most recent assessment.
But global temperatures have unequivocally become hotter, and hotter conditions precipitate extreme weather —including severe drought. Hotter conditions also reduce snowpack, which provides a key source of water supply and natural water storage in many regions.
Regionally, the driest parts of the earth are getting drier, while the wettest parts are getting wetter. Looking forward, as temperatures continue to rise, the IPCC and other researchers anticipate an intensification of those regional trends. But by limiting our climate change contributions, reducing water waste, and using water more efficiently, we can prepare for —and maybe even curb—future dry spells.
The impact of climate change, including more severe drought, can be mitigated only when countries, cities, businesses, and individuals shift away from the use of climate-warming fossil fuels to cleaner renewable energy sources. It will succeed only if countries go beyond their commitments, and that includes the United States. Fortunately, American states and cities , as well as more than 2, U.
Actions include speaking to local and congressional leaders about regional environmental policies and finding ways to cut carbon pollution from your daily life. Aging infrastructure—faulty meters, crumbling pipes, leaky water mains—costs the United States an estimated 2. Meanwhile, a single leaky faucet—releasing just three drips a minute—wastes more than gallons of water in a year. States, cities, water utilities, businesses, and citizens can curb water waste by investing in climate-smart strategies.
These include repairing leaky infrastructure from utility pipes to the kitchen faucet , boosting water efficiency with the use of water- and energy-efficient technologies and appliances such as clothes washers , and adopting landscape design that makes use of drought-tolerant plants and water-efficient irrigation techniques.
In California, these strategies alone could reduce water use by as much as 60 percent. Transparency and accountability. How money is spent. Annual reports. How we are governed. Codes and policies. Supply chain. Donate to Concern. Through to 2. Hunger crisis appeal. Donating by post and phone. Corporate giving. Make a corporate donation. Partner with us. Payroll giving. Emergency support. Other ways to give. Women of Concern. Donate in memory.
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London Marathon. Climb for Concern. Start your own fundraiser. Charity fundraising tips. Schools and youth. Debate resources. Become a Hunger Hero. Defining a drought can be tricky. They can happen over a long period and can be devastating to both the economy and human life. During a drought, there is so little rain that an entire region can start to dry out.
When little or no rain occurs, plants and crops can die because the soil is too dry for them to grow. When rainfall is less than normal for several weeks, months, or even years, water levels start to fall dramatically.
If dry weather continues and water-supply problems develop, the dry period can become a drought.
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