Drought Sweeps Nation: Part I
(This article is the first in a two-part series about drought in the 20th century and tools that lessen the impact.)
December 2, 2012
October 2012 ended a 16-month stretch of above-average U.S. temperatures, making the warmth of 2012 one for the history books. This year's unseasonably dry months is anticipated to lower crop harvest, potentially causing farmers, ranchers and other members of the agriculture industry to suffer devastating economic and emotional loss. With millions in damages from brush fires igniting thousands of acres, brown crop fields in the nation's top corn and soybean producers in Iowa, to the drying of the Lower Platte River in Nebraska, this year's extreme heat and wide spread drought invokes images of the great Dust Bowl of the 1930s. In July, the United States Department of Agriculture announced that more than 1,000 counties in 26 states qualified as natural disaster areas.
The NOAA State of the Climate Report for August 2012 indicated that about 62.3 percent of the contiguous U.S. was classified as experiencing moderate to exceptional drought at the end of August. Even the heavy rains from Hurricane Isaac brought little relief in September. NOAA's satellite observing and forecasting tools helped predict the impact of these dry and sweltering heat conditions. Here, we will discuss some drought highlights of the 20th Century and in Part II, tools that may lessen the drought's impact.
What is a Drought?
Drought is the prolonged absence of water, in this case, rain water. This complex, creeping phenomenon is difficult to monitor and define, sneaks up slowly, impacts many sectors of the economy, and operates on many different time scales. As a result, the climatological community has defined four types of drought: 1) meteorological drought, 2) hydrological drought, 3) agricultural drought, and 4) socioeconomic drought. According to NOAA, many different indices have been developed over the decades to measure drought in these various sectors. The U.S. Drought Monitor depicts drought integrated across all time scales and differentiates between agricultural and hydrological impacts. (http://www.ncdc.noaa.gov/climate-monitoring/dyk/drought-definition)
On the Rio Grande—historically the wellspring for more than five million people in Colorado, New Mexico, Texas, and Mexico—coping with scarcity has become a reality, and water management and use in the region may be a leading example of how to adapt to drier times. Read about drought on the Rio Grande at: http://www.climatewatch.noaa.gov/article/2012/drought-on-the-rio-grande.
Some Major 20th Century Droughts in the U.S.
In terms of duration and spatial extent, the 1930s Dust Bowl drought is considered to be the major drought of the 20th century. It lasted for up to seven years and resulted in the mass migration of millions of people from the Great Plains to the western U.S. In the aftermath of the drought, farmers in this region adopted new cultivation methods which lessen the impact of subsequent droughts.
It is no question that the drought of the 1950s hampered the benefits of the post-war economic growth and technological advancements for many Americans. Many residents of the Great Plains and southern United States were suffering from a drought that lasted approximately five years. In three of these years, dry conditions spread from coast to coast. Finally, with the spring rains of 1957, the drought subsided.
But during that time of the drought, crop yields dropped as much as 50 percent and grass became scarce, hay prices skyrocketed, forcing many ranchers to feed their cattle a mixture of prickly pear cactus and molasses. According to published reports, the drought was first felt in the southwestern U.S. in 1950 and spread to Oklahoma, Kansas and Nebraska by 1953. When the drought subsided, many counties across the region were declared a federal drought disaster.
The drought of 1988 also affected much of the nation's corn and soybean growing areas. It began along the west coast and extended into northwestern U.S., with its greatest impact in the northern Great Plains. From the pumping of ground water to almost deletion and to low river levels in the upper Mississippi River Basin creating major barge navigation challenges, this drought also created ideal grounds for furious forest fires. The Yellowstone fire is another known devastating event of the 1988 drought.
In the next update, “Drought Sweeps Nation Part II” we'll look at today's drought and how satellite data are used to study its impacts on America.
Drought Sweeps Nation: Part II
Tracking Climate, Wildfires, and Heavy Rains with NOAA's Satellite Technology