As some 60 million Americans on the east coast prepare for the worst nor’easter in a decade, nearly 84 million across the US are experiencing some level of drought.
The west and southwest areas were hit with a drought this past spring that continued and intensified through the summer, fall and now into the winter months.
A number of southwest states, including Arizona, Utah, Colorado, New Mexico and west Texas, are experiencing an exceptionally prolonged period of abnormally low rain fall – 30 percent of the US is currently ranked at this level.
Benjamin Cook, a climate scientist at NASA’s Goddard Institute for Space Studies, said: ‘Compared to late 2019 and early 2020, when there was very little drought in the continental United States, this is quite an extreme single-year event that developed rapidly over the course of 2020.’
‘But if you look over longer time scales, I would argue this is really a continuation of a multi-decadal event that began around 2000.’
‘There have been some breaks, but the Southwest has been in more-or-less continuous drought conditions since then.’
A number of southwest states, including Arizona, Utah, Colorado, New Mexico and west Texas, are experiencing an exceptionally prolonged period of abnormally low rain fall – 30 percent of the US is currently ranked at this level
MLive suggests that the continuing droughts could foreshadow summer of next year, which will be a hurdle for the agriculture industry that populates these areas.
NASA shared maps designed with data from the Drought Monitor that show how levels progress across the nation in shades of organ to red on December 8.
States in the center of the US, like Michigan and South Dakota, are listed as ‘Abnormally Dry,’ but the shades become dark as it moves west.
Parts of Utah, Wyoming, New Mexico and west Texas are in an ‘Exceptional Drought,’ and nearly all of Arizona is a dark red.
A second map depicts percentage of groundwater, with the same states showing the lowest amount. The colors highlight the wetness percentile, showing how the levels of groundwater compare to long-term records for the month
A second map depicts percentage of groundwater, with the same states showing the lowest amount.
The colors highlight the wetness percentile, showing how the levels of groundwater compare to long-term records for the month.
Blue areas have more abundant water than usual, and orange and red areas have less.
The darkest reds represent dry conditions that should occur only two percent of the time (about once every 50 years).
Christopher Hain, a research meteorologist at NASA’s Marshall Space Flight Center, said: ‘The Southwest monsoon was underwhelming this year, and many places in that region rely on that precipitation as part of their water budgets.’
‘Given the La Niña happening now, there is a higher-than-normal chance that winter rains will not help much and below-average precipitation will further exacerbate the drought.’
‘That could set the stage for even worse conditions next spring, summer and fall.’
La Niña—cooler than normal sea-surface temperatures in the central and eastern tropical Pacific Ocean—tends to cause dry weather in the southwest.
The associated weather patterns push the jet stream north and cause it to curve, driving storms to the Pacific Northwest and the Great Plains instead.
‘The long-term, multi-decadal drought is largely driven by precipitation deficits connected to persistently cold sea surface temperatures in the eastern tropical Pacific—in essence a string of years with long-lasting and intense La Niñas,’ said Cook.
‘However, there is strong evidence from climate models and centuries of tree ring data that suggest about one-third to one-half of the severity of the current drought can be attributed to climate change.’