More than 95 percent of the Western US is in some level of drought for the past several weeks, and seven states are entirely in drought: California, Nevada, Oregon, Idaho, Utah, Montana, and North Dakota on the list.
More than 100 large wildfires were burning in 12 states as of Thursday, including the Caldor Fire in Northern California, which grew 24 times its size over the course of two days.
Scientists say the multi-year drought is a clear sign of how the climate crisis is affecting not only the weather, but water supply, food production and electricity generation.
Seven states remain entirely in drought conditions, according to the US Drought Monitor: California, Oregon, Nevada, Utah, Idaho, North Dakota and Montana.
A record 22.4% of the country is in the worst two categories of drought this week — extreme and exceptional. This is the third consecutive week this record has been set and is being driven by expanding drought in the Midwest.
Drought worsened significantly in Minnesota, according to the Drought Monitor, where “hydroelectric power generation along the Mississippi River halted near St. Cloud. River levels in the state lowered towards 1988 drought levels, creating a danger for boats to scrape along the bottoms of rivers.
But the worst drought conditions are in the West, with more than 95 percent of the region in some level of drought and nearly two-thirds in extreme or exceptional drought.
In addition to fueling devastating wildfires, drought in the Northwest is having a significant impact on agriculture — with 38% of Washington state and 25% of Oregon are in ‘exceptional’ drought, the highest category, both records for the states.
Monsoon rains relieved the drought in the Southwest, the Drought Monitor reported.
“Widespread improvements in drought conditions occurred in Arizona and New Mexico this week, as heavy monsoonal rains made their return,” the report noted. While long-term drought remains in these states, “recent conditions have been wet enough from a green-up in vegetation.”
As the planet warms, drought and extreme heat will also fuel deadly wildfires. Multiple studies have linked rising carbon dioxide emissions and high temperatures to increased acreage of burning across the West, particularly in California.
The West experienced extremely low rain and snowfall over the past year, compounded by drastically high temperatures. Less rain and increasing heat waves have led directly to drought conditions and water shortages.
As climate change accelerates and winter temperatures increase, snowfall will decrease. High-elevation snowpack serves as a natural reservoir that eases drought, storing water through the winter months and slowly releasing it through the spring melting season.
Stream and river flow
Streamflow, a measure of how much water is carried by rivers and streams, is another significant indicator of drought and its impact.
As drought conditions have worsened in 2021, hundreds of stream and river locations are experiencing below-average flow. More than 50 percent of the western monitoring stations reported lighter-than-usual flows. Fishing restrictions have also been put in place on many rivers in Montana due to low flows and warm waters.
Changes in streamflow affect the water supply for our own municipal use, crop irrigation and power generation.