Climate change is spurring a new, deep dive into a complex, little-studied weather system blamed for creating billions of dollars in flood damage across the western U.S.
Atmospheric rivers are narrow ribbons of concentrated moisture that originate in the Pacific and can flow thousands of miles before dropping rain and snow on land. Scientists are ramping up their research into the systems this winter fearful that warmer temperatures tied to climate change will boost the moisture they carry, supercharging them moving forward.
“Hurricane hunter” planes are set to fly at least 12 missions directly into the systems, double last year’s number, to gather a wide range of meteorological data. At the same time, 100 new ocean buoys will monitor how the systems form. The goal: Better warning processes to stave off flooding.
“It is 100% completely saturated air,” said Rich Henning, a flight director for the National Oceanic and Atmospheric Administration who conducts onboard weather observations. “If you’re ever wondering how six feet of snow can fall in the Cascades in one day, this is exactly how all that moisture is transported.” (...)
A study released in December by Scripps and the Army Corps of Engineers found that atmospheric rivers caused 84% of the flood damage suffered in 11 western states over 40 years through 2017. The average annual cost: $1.1 billion, according to the report.
“In a warmer climate,” the study concluded, atmospheric rivers will be “more intense as they become wetter, longer, and wider; there is some indication that this is already happening.”
It won’t take much of a temperature change to boost their moisture content, according to John Dickson, a flood researcher who is the chief executive officer of Aon Edge, a Montana-based flood insurance provider. A rise of just 1.8 degrees Fahrenheit can boost water vapor in the air by 7%, he said.
“Our world continues to change and our land use practices are constantly evolving,” Dickson said., “Yet we rely on risk management tools that are decades old to navigate the current times.”
Besides helping forecasts in the western U.S., the new data will have international significance, since the rivers can originate in oceans worldwide.
“There has been an amazing amount of research on the hurricane problem and tornadoes and nor’easters,” said Marty Ralph, a Scripps scientist. “But it turns out atmospheric rivers are a real issue on the West Coast, and they have not really had that much attention.”
Atmospheric rivers are narrow ribbons of concentrated moisture that originate in the Pacific and can flow thousands of miles before dropping rain and snow on land. Scientists are ramping up their research into the systems this winter fearful that warmer temperatures tied to climate change will boost the moisture they carry, supercharging them moving forward.
“Hurricane hunter” planes are set to fly at least 12 missions directly into the systems, double last year’s number, to gather a wide range of meteorological data. At the same time, 100 new ocean buoys will monitor how the systems form. The goal: Better warning processes to stave off flooding.
“It is 100% completely saturated air,” said Rich Henning, a flight director for the National Oceanic and Atmospheric Administration who conducts onboard weather observations. “If you’re ever wondering how six feet of snow can fall in the Cascades in one day, this is exactly how all that moisture is transported.” (...)A study released in December by Scripps and the Army Corps of Engineers found that atmospheric rivers caused 84% of the flood damage suffered in 11 western states over 40 years through 2017. The average annual cost: $1.1 billion, according to the report.
“In a warmer climate,” the study concluded, atmospheric rivers will be “more intense as they become wetter, longer, and wider; there is some indication that this is already happening.”
It won’t take much of a temperature change to boost their moisture content, according to John Dickson, a flood researcher who is the chief executive officer of Aon Edge, a Montana-based flood insurance provider. A rise of just 1.8 degrees Fahrenheit can boost water vapor in the air by 7%, he said.
“Our world continues to change and our land use practices are constantly evolving,” Dickson said., “Yet we rely on risk management tools that are decades old to navigate the current times.”
Besides helping forecasts in the western U.S., the new data will have international significance, since the rivers can originate in oceans worldwide.
“There has been an amazing amount of research on the hurricane problem and tornadoes and nor’easters,” said Marty Ralph, a Scripps scientist. “But it turns out atmospheric rivers are a real issue on the West Coast, and they have not really had that much attention.”
by Brian K. Sullivan, Bloomberg | Read more:
Image: NOAA Environmental Visualization Laboratory
