The end of a drought can occur as gradually as it began. Dry periods can last for 10 years or more. During the 's, most of the United States was much drier than normal. In California, the drought extended from to In Missouri, the drought lasted from to That extended dry period produced the "Dust Bowl" of the 's when dust storms destroyed crops and farms.
The first evidence of drought usually is seen in records of rainfall. Within a short period of time, the amount of moisture in soils can begin to decrease. The effects of a drought on flow in streams and reservoirs may not be noticed for several weeks or months. Water levels in wells may not reflect a shortage of rainfall for a year or more after a drought begins Moreland, A period of below-normal rainfall does not necessarily result in drought conditions.
Some rain returns to the air as water vapor when water evaporates from water surfaces and from moist soil. Plant roots draw some of the moisture from the soil and return it to the air through a process called transpiration. The total amount of water returned to the air by these processes is called evapotranspiration. Sunlight, humidity, temperature, and wind affect the rate of evapotranspiration.
When evapotranspiration rates are large, soils can lose moisture and dry conditions can develop. During cool, cloudy weather, evapotranspiration rates may be small enough to offset periods of below-normal precipitation and a drought may be less severe or may not develop at all Moreland, Rainfall in any form will provide some drought relief. A good analogy might be how medicine and illness relate to each other.
A single dose of medicine can alleviate symptoms of illness, but it usually takes a sustained program of medication to cure an illness. Likewise, a single rainstorm will not break the drought, but it may provide temporary relief. A light to moderate shower will probably only provide cosmetic relief. It might make folks feel better for awhile, provide cooling, and make the vegetation perk up. During the growing season, most of the rain that falls will be quickly evaporated or used by plants.
Its impact is short term. A thunderstorm will provide some of the same benefits as the shower, but it also may cause loss of life and property if it is severe. Thunderstorms often produce large amounts of precipitation in a very short time, and most of the rain will run off into drainage channels and streams rather than soak into the ground. If the rain happens to fall upstream of a reservoir, much of the runoff will be captured by the reservoir and add to the available water supply.
No matter where the rain falls, stream levels will rise quickly and flooding may result. Also, because the rainfall and runoff can be intense, the resulting runoff can carry significant loads of sediment and pollutants that are washed from the land surface. Each time you run the dishwasher, you use 4 to 6 gallons of water.
Droughts are a sign of a stressed and imbalanced ecosystem. If we each take the time to really understand what causes drought and acknowledge the consequences it can have on mankind, we can begin to become part of the solution, rather than continuing to add to the problem. The at-home tips for conserving water are actionable, easy to implement, and necessary. And, along with saving water, you can also try to reduce your carbon footprint which reduces climate change, the root cause of droughts.
Deborah Tayloe is a freelance content writer and blogger who often contributes to GutterBrush. Edited by: Hugh. Mining remains an essential and growing part of the modern industry. However, many mining techniques still in use can have serious impacts on both the mining site itself and…. Get out there, and help the Earth. Save Money!
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There are now more gadgets than the number of people around the world. This site uses Akismet to reduce spam. Learn how your comment data is processed. Water is a renewable resource because it travels through the oceans, rivers, ground, and atmosphere; it is always moving!
It falls from the sky as rain or snow into our oceans, lakes, and rivers and onto land. Precipitation that falls on the land enters the groundwater through percolation or travels to streams, rivers, and lakes as runoff. Water in streams and rivers is carried to the oceans, where it evaporates and forms clouds—where the cycle starts all over again! Water is also a limited resource.
We will always have the same amount of water on the earth, but we can't always use as much as we need. One reason is that 97 percent of the earth's water is saltwater, and saltwater is not good for people and wildlife and many plants. Of the remaining 3 percent, which is freshwater, nearly 75 percent is frozen in glaciers, making it unavailable to us. Another reason that water is a limited resource is that pollution , increased human demand for water, and changes in precipitation patterns can decrease both the quality and amount of water available to people, plants, and wildlife.
Water evaporating from the oceans, lakes, rivers, and streams moves to the atmosphere. Air carries the moisture up, and if conditions are right, it forms clouds. Wind moves these clouds around the globe. The wind that carries the clouds that bring rain is called the jet stream. The jet stream changes its pattern with each season. In other words, the jet stream will carry weather patterns, such as precipitation and temperature, in different directions or over different routes during each season.
When the jet stream hits a road block or takes a certain detour and is not bringing the clouds that produce rain, a drought can occur. This is called a flash drought. A drought is caused by drier than normal conditions that can eventually lead to water supply problems.
Really hot temperatures can make a drought worse by causing moisture to evaporate from the soil. Just because a region is hot and dry doesn't necessarily mean it is going through a drought. Droughts only occur when an area is abnormally dry.
Here's why:. Some regions are routinely wet and others are routinely dry. From season to season — and from year to year — the amount of rain or snow in a location can vary. However, over a period of many years, the average amount of precipitation in a region is fairly consistent. For example, in the deserts of the American Southwest, the average precipitation is less than 3 inches per year.
But, the average yearly precipitation in Atlanta is about 50 inches.
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