Humans, ocean shaped North American climate over past 50 years, says NOAA

Science Daily, via NOAA: Greenhouse gases play an important role in North American climate, but differences in regional ocean temperatures may hold a key to predicting future U.S. regional climate changes, according to a new NOAA-led scientific assessment. The assessment is one in a series of synthesis and assessment reports coordinated by the U.S. Climate Change Science Program.

This latest assessment, Reanalysis of Historical Climate Data for Key Atmospheric Features: Implications for Attribution of Causes of Observed Change, describes what has changed—and why—in North America’s climate over the past half century. The assessment addresses the likelihood and extent to which human activity or natural variations have driven surface warming, precipitation, droughts, and floods.

“A major implication of this assessment is that improving predictions of regional sea-surface temperatures will be crucial to predicting climate variability across the U.S. from years to decades, as well as projecting long-term regional climate changes,” said Randall Dole, lead author and a scientist at NOAA’s Earth System Research Laboratory in Boulder, Colo.

…Drought impacts have likely become more severe as surface temperatures warmed, increasing evaporation, reducing soil moisture, and causing other water stresses. The scientists found no long-term trends in where or how often droughts occur or in how much rain or snow has fallen on average each year.

…“Using reanalysis and attribution methods we can now say with more confidence what’s driving some of the extreme climate conditions of the past few years: whether it’s global warming, El Niño, La Niña, or some other pattern,” said NOAA scientist Martin Hoerling, also of the Earth System Research Laboratory and a lead author on the report. “That’s the information policymakers and the public ask for.” Hoerling also heads NOAA’s climate attribution team….


Adriaen van der Kabel (1659-1705), "Stormy sea with boats and nearby cliff"