How unhealthy is the drought within the western United States? A surprising depiction of the report dry spell is available in pictures of Lake Mead, the reservoir fashioned by the Hoover Dam on the Colorado River. NASA satellite tv for pc pictures, beneath, from Landsat 7 and Landsat 8 present the distinction in lake ranges between August 2000 and August 2021.
Comparative Landsat satellite tv for pc pictures of Lake Mead from August 7, 2000 (left) and August 9, 2021 (proper). Credit score: NASA
In keeping with the U.S. Bureau of Reclamation, the water stage within the reservoir — which provides ingesting water to thousands and thousands of individuals in California, Arizona, Nevada, and a part of northern Mexico — was measured at its lowest stage for the reason that lake was created with the damming of the Colorado River in 1935.
Information exhibits that as of August 22, 2021, Lake Mead was stuffed to simply 35 % of its capability. The low water stage comes at a time when 95 % of the land in 9 Western states is affected by some stage of drought (64 % is excessive or worse). It continues a 22-year megadrought which may be the area’s worst dry spell in twelve centuries.
The picture from 2021 exhibits tan “fringes” alongside the shoreline in 2021, that are areas of the lakebed that might be underwater when the reservoir is stuffed nearer to capability. This phenomenon is also known as a “bathtub ring.”
The lake elevation knowledge, proven beneath, says that on the finish of July 2021, the water elevation on the Hoover Dam was 1067.65 toes (325 meters) above sea stage, the bottom since April 1937, when the lake was nonetheless being stuffed. The elevation on the finish of July 2000—across the time of the Landsat 7 pictures – was as 1,199.97 toes (341 meters).
Information by way of the U.S. Bureau of Reclamation and NASA.
At most capability, Lake Mead reaches an elevation 1,220 toes (372 meters) close to the dam and would maintain 9.3 trillion gallons (36 trillion liters) of water. The lake final approached full capability within the summers of 1983 and 1999. It has been dropping ever since.
Lake Mead is the most important reservoir in america and a part of a system that provides water to at the least 40 million folks. The report low ranges within the reservoir means much less water will likely be portioned out to some states within the 2022 water yr, and the U.S. Bureau of Reclamation stated that “the reductions characterize the primary “scarcity” declaration—demonstrating the severity of the drought and low reservoir situations.”
Sources and additional studying: NASA Earth Observatory, U.S. Bureau of Reclamation