Scripps climate scientist Marty Ralph is an expert in atmospheric rivers , a vital water resource .
Climate change has come to affect nearly every facet of human life — from economics to public health and safety .
Mike Dettinger , research hydrologist at Scripps Institution of Oceanography , has cited historic precedent for potential “ megafloods ” in California .
“ The short answer is we ’ re doing pretty much nothing globally ,” says Victor , in response to how various changes are likely to impact the future world , from rising sea levels to increased precipitation .
In a controversial Nature editorial coauthored with Scripps Director Emeritus Charles Kennel , Victor suggests that widely accepted success metrics for mitigation are a large part of the complacency problem . For a decade , the general consensus has been to limit the global surface air temperature increase to 2 degrees Celsius ( 3.6 degrees Fahrenheit ). The fact that temperature growth has flatlined since 1998 has encouraged a dismissive attitude among the public and policymakers , never mind the many possible explanations . Scripps researchers have linked the flatline to the last major El Niño warming event , for example .
“ Scientifically , there are better ways to measure the stress that humans are placing on the climate system than [ this ] growth ,” argue Victor and Kennel . “ It ’ s allowed governments to ignore the need for massive adaptation to climate change .”
The researchers suggest using other indicators , or “ vital signs ,” such as studying the ocean , which absorbs 93 percent of Earth ’ s excess heat , and a greater scrutiny of areas that are more sensitive to climate change , such as the Arctic , which has rapidly warmed since 1998 .
Aastating floods .
Boots on the Ground , Eyes in the Air
Atmospheric rivers are corridors of concentrated moisture that deliver as much as half of the precipitation received by California and the West during short , intense bursts that last only a matter of days . They drop rain and snow that is crucial to water supplies , especially in parched areas like the Southwest . But their promise does come at a price , as the largest , strongest atmospheric rivers can cause extreme rainfall and dev-
Climate scientist Marty Ralph is director of the new Center for Western Weather and Water Extremes at Scripps . His research is focused on atmospheric rivers and their role in the global water cycle , including water vapor transportation , precipitation and runoff . He was also an integral part of the multiagency CalWater 2015 campaign in February , which included one of the largest projects ever devoted to an individual atmospheric river event .
Ralph says adequate forecast accuracy for atmospheric rivers could perhaps give water
reserve managers more flexible control over resources , while at the same time offering more protection from flooding .
Ralph ’ s colleague at Scripps , Mike Dettinger , described what such a flood might look like in a prominent Scientific American feature , “ The Coming Megafloods .” The piece opens with an ominous reference to 1861 , when rain started pounding the state on Christmas Eve and didn ’ t abate for 43 days , turning California ’ s Central Valley into a 300-mile-long inland lake . Thousands of people died in the deluge , along with a quarter of the state ’ s 800,000 cattle . Raging floodwaters washed away everything in their path , including entire communities . The state went bankrupt .
“ If such a storm hit today , we ’ d experience something like $ 500-700 billion in damages and economic destruction ,” says Ralph . “ Those are huge numbers compared to [ Hurricanes ] Katrina ($ 100 billion ) and Sandy ($ 200 billion ). It ’ s a major challenge . These types of storms are out there , and they will happen eventually .”
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