Friday, April 18, 2014

California Suffers Astonishingly Fast Snowpack Melt as Drought Intensifies

The dry bed of the Stevens Creek Reservoir is seen on Thursday, March 13, 2014, in Cupertino, Calif.
IMAGE: MARCIO JOSE SANCHEZ/ASSOCIATED PRESS


California Suffers Astonishingly Fast Snowpack Melt as Drought Intensifies
ANDREW FREEDMAN, April 18, 2014  mashable.com

The severe drought that threatens water supplies and a potentially devastating wildfire season is deepening and locking into place across much of the far West, Southwest and Southern Plains, according to new climate data released Thursday.

In California's Sierra Nevada Mountains, where runoff from the spring snowpack provides much-needed water supplies during the dry season, half of the snowpack's liquid water equivalentmelted in just the past week in some areas, due to temperatures that soared as high as 12 degrees Fahrenheit above average of early April, according to the U.S. Drought Monitor.

To make matters worse, the sudden snow melt in California barely boosted reservoir supplies, which remain well below average across the state.

Officials already knew that the snowpack was unusually thin and would provide below average amounts of water when it melted, considering that the state had its third-driest winter on record, following its driest calendar year in 2013. However, they did not anticipate it would melt so quickly.

The California state snow survey on April 1 found that the snowpack contained just 32% of the average water content at that time of year, when snowpack typically reaches its annual peak. This placed 2014 as among the lowest water-content years on record since such data began in 1930.

The California drought is part of a broader regional drought that encompasses parts of Oregon, Nevada, Colorado, Utah, Arizona, New Mexico, Texas and Oklahoma, among other areas. In a conference call with reporters on Thursday, scientists from the National Oceanic and Atmospheric Administration (NOAA) said the California drought is likely to persist throughout the summer, after average precipitation fell during March. This precipitation failed to make up for the deep precipitation deficits the state had been running.
Southern Plains Drought

According to NOAA, drought has expanded and intensified in the Southern Plains as well, where parts of Oklahoma and Texas have been stuck in devastatingly arid conditions since 2010. The geographic extent of extreme and exceptional drought has increased nearly four-fold in Texas, more than five-fold in Oklahoma, and nearly six-fold in New Mexico since the beginning of winter, according to David Brown, a NOAA climate specialist.

New Mexico has had its third-driest start to the year, and Oklahoma and Texas have each had their sixth-driest starts to the year, Brown says.

Nearly two million Southern Plains residents are currently living in areas with "extreme" or "exceptional" drought conditions, which are the two worst categories on the Drought Monitor's scale. The number of affected residents more than doubled since the start of winter, according to Brown. Most of these people are in west Texas and the Texas panhandle, including the cities of Lubbock, Amarillo and Wichita Falls.

Drought Monitor image showing the extent and severity of drought conditions across Texas on April 17, 2014. The dark red areas are where the drought is most intense. IMAGE: U.S. DROUGHT MONITOR

In Wichita Falls, city officials are preparing to raise their water restrictions to an unprecedented "Stage 5" emergency, which would trigger dramatic restrictions on water use. The city also plans to spend $300,000 on cloud seeding this spring, to try to increase rainfall production from thunderstorms. Cloud seeding, which can increase rainfall slightly under specific circumstances, has no chance of alleviating the drought itself, but it could provide some short-term benefits.

Since the start of the drought in October 2010, Wichita Falls has had about 58 inches of rain (and melted snow and ice), Brown said. The typical amount for that period of time is 100 inches. This means that the city needs to make up about a year and a half's worth of precipitation.
Alleviating the drought this spring and summer, Brown says, "would really take an unprecedented amount of spring rainfall.”Alleviating the drought this spring and summer, Brown says, "would really take an unprecedented amount of spring rainfall.”

Victor Murphy, a NOAA meteorologist, gave Mashable further details on Wichita Falls' plight. He said data shows that the past 42 months have been the driest such consecutive period on record in that city, eclipsing any of the drought years in the 1950s and the 1930s "Dust Bowl" era. For water planning purposes, the early 1950s drought is considered to be the drought of record, meaning that the current drought is worse than what policymakers may have prepared for.

The drought is raising concerns about wildfires and massive dust storms this summer, and has already caused an agricultural disaster in the Southern Plains. Texas cattle herds have thinned out, as ranchers are forced to send them to meat plants earlier than planned, or move them northward to states that have water. In response to the drought conditions from Oklahoma to California, meat prices have spiked to their highest level since 1987, and egg prices have also risen by nearly 10% compared to last year, according to the March Consumer Price Index report. Avocado prices are also going up in response to the California drought.

Although May and June are Texas and Oklahoma's wettest months on average, there is such a big rainfall deficit in parts of these states that the drought will almost certainly not be fully eliminated.

If an El NiƱo event develops as expected by the fall, it could lead to unusually wet conditions from California to Texas next winter, but that is neither guaranteed to happen, nor would it be of any help in the short-term.

While the drought conditions in California and Texas were likely initially triggered by natural variability, such as ocean temperature patterns in the Pacific and Atlantic Oceans, studies show that manmade global warming can intensify such conditions by raising temperatures and increasing evaporation. In addition, a new study found that manmade global warming likely intensified the weather pattern that has kept California so dry since 2013.

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