Coastal Observatories to Watch Atmospheric Rivers
A partnership that includes the California Department of Water Resources is installing the first of four weather stations designed to study “atmospheric rivers,” a weather pattern that brings sustained heavy rainfall and the potential for flooding.
An atmospheric river dumped several inches of rain and snow in Northern California last weekend. This winter weather pattern is characterized by a narrow band of concentrated precipitation that can stretch for hundreds or thousands of miles.
This month scientists affiliated with the National Oceanic and Atmospheric Administration began installing a custom-built weather instrument array in Bodega Bay, to be followed by three more at Eureka, Point Sur and Goleta. The work is expected to be finished in early 2014.
DWR, NOAA, Scripps Institution and the University of California at San Diego are partnering on this project, according to an announcement by NOAA.
The four coastal observatories will carry standard meteorological instruments, GPS that measures the total water vapor above, and a Doppler system capable of measuring the speed and direction of wind at several altitudes.
The wind data will be particularly valuable because weather satellites and offshore detectors don’t collect data on strong low-altitude winds, a signature of an approaching atmospheric river.
“With our new sensors, we’ll be able to measure those winds and more, to understand just how much moisture is moving in, which largely controls how extreme the precipitation inland will become,” stated Martin Ralph, a research meteorologist and branch chief in NOAA’s Earth System Research Laboratory in Boulder, Colo. “This information will ensure that meteorologists and emergency managers have additional information to keep the public informed about these potentially destructive storms.”
The four coastal observatories should help California officials anticipate whether incoming storms will bring snow, heavy rain or floods. The observatories eventually will be integrated into a statewide weather monitoring system of soil moisture sensors and snow-level radar that tracks atmospheric rivers and other weather systems producing heavy precipitation.