Study links changing winds to warming in Pacific

  • By JEFF BARNARD
  • Monday, September 22, 2014 10:50pm
  • News

A new study released Monday found that warming temperatures in Pacific Ocean waters off the coast of North America over the past century closely followed natural changes in the wind, not increases in greenhouse gases related to global warming.

The study compared ocean surface temperatures from 1900 to 2012 to surface air pressure, a stand-in for wind measurements, and found a close match.

“What we found was the somewhat surprising degree to which the winds can explain all the wiggles in the temperature curve,” said lead author Jim Johnstone, who did the work while a climatologist at the Joint Institute for the Study of the Atmosphere and Ocean at the University of Washington.

ADVERTISEMENT
0 seconds of 0 secondsVolume 0%
Press shift question mark to access a list of keyboard shortcuts
00:00
00:00
00:00
 

“So clearly, there are other factors stronger than the greenhouse forcing that is affecting those temperatures,” he added.

The study released by the online edition of the peer-reviewed journal Proceedings of the National Academy of Sciences does not question global warming, but argues there is evidence that in at least one place, local winds are a more important factor explaining ocean warming than greenhouse gases.

It was greeted with skepticism by several mainstream climate scientists, who questioned how the authors could claim changes in wind direction and velocity were natural and unrelated to climate change.

They pointed out that the study sees a correlation but did not do the rigorous statistical and computer analysis to show that the cause of the wind changes were natural — the kind of analysis done when scientists attribute weather extremes to global warming.

“This may say more about the state of climate modeling than it says about causes of warming in the Pacific Northwest,” Ken Caldeira, an atmospheric scientist at the Carnegie Institution for Science’s Department of Global Ecology, said in an email. “The authors … have not established the causes of these atmospheric pressure variations. Thus, claims that the observed temperature increases are due primarily to ‘natural’ processes are suspect and premature, at best.”

Johnstone and co-author Nathan Mantua, a research scientist with the NOAA Fisheries Service in Santa Cruz, California, pointed to the fact that one steep ocean warming period from 1920 to 1940 predates the big increases in greenhouse gases, and an ocean cooling period from 1998 to 2013 came while global average temperatures were at or near all-time highs.

They also noted that the wind changes consistently preceded the ocean surface temperature variations by about four months, showing the wind was causing the changes to temperature, not the other way around.

James Overland, a research oceanographer at the NOAA Pacific Marine Environmental Laboratory, said the study reinforced findings that the North Pacific has a lot of natural variability in 5- to 20-year time scales, and he reached the same conclusions on changes in the Bering Sea.

“Natural variability cannot be ruled out as an important mechanism,” he said in an email.

During the entire period from 1900 to 2012, there has been an increase of about 1 degree Fahrenheit in ocean surface temperatures in the area from Hawaii to Alaska, and down the coast to British Columbia, Washington, Oregon and California, according to the study.

The wind acts to change temperature through speed and direction. When the wind blows faster across the water, evaporation increases, and like sweat drying on the skin, cools the water surface. Winds from the south drive warmer air and water to the region. Winds from the north drive in colder air and water.

Mantua said he and Johnstone took the potential inaccuracy of the data into account, comparing it to several other sources, including land surface air temperatures along the coast, which also agreed.

“It just seems to us it’s a pretty simple story,” Mantua said. “Yet it’s going to take people by surprise, because it is ingrained in our minds that if the climate warms up in the course of the century, it’s probably because of global warming, the increase in the concentration of greenhouse gases and other things humans have done that have pushed it in a warming direction.”

AP Science Writer Seth Borenstein contributed to this report.

More in News

Robert Weaver was last seen at the Doroshin Bay public use cabin on June 25, 2025. (Photo provided by the Kenai National Wildlife Refuge)
Kenai wildlife refuge seeking information on missing man

Robert Weaver was last seen near Skilak Lake on June 25.

The Alaska Dive Search Rescue and Recovery Team conducts a training mission in Seward, Alaska in 2024. Photo courtesy of the Alaska Dive Search Rescue and Recovery Team
Anchor Point fundraiser to benefit Alaska rescue and recovery group

Alaska Dive Search Rescue and Recovery Team is an all-volunteer nonprofit organization established in 2016.

Kachemak Bay Family Planning Clinic staff (left to right) Angie Holland, RN; Jane Rohr, Sonja Martin Young, CNM; Robin Holmes, MD; and Cherie Bole, CMA provide an array of reproductive and sexual health services. (Photo provided by KBFPC)
Kachemak Bay Family Planning Clinic releases report on STI trends on the Kenai Peninsula

The report pulls from data gathered from 2024 to early 2025.

Pool manager and swim coach Will Hubler leads a treading water exercise at Kenai Central High School in Kenai, Alaska, on Tuesday, June 17, 2025. (Jake Dye/Peninsula Clarion)
Swimmers, parents call on Kenai to support Kenai Central pool

The KPBSD Board of Education last week said communities will need to step up and take over administration of pools within the next year.

Traffic passes by South Spruce Street in Kenai, Alaska, on Tuesday, June 10, 2025. (Jake Dye/Peninsula Clarion)
Kenai drops effort to rename South Spruce Street

The resolution would have changed the name to make it clear which road led to North Kenai Beach

Gov. Mike Dunleavy compares Alaska to Mississippi data on poverty, per-pupil education spending, and the 2024 National Assessment of Education Progress fourth grade reading scores during a press conference on Jan. 31, 2025. Alaska is highlighted in yellow, while Mississippi is in red. (Jasz Garrett / Juneau Empire)
Dunleavy calls special session for August

Lawmakers on Wednesday said they were surprised by the move.

A makeshift coffin decrying the risks of Medicaid funding cuts is seen on Thursday, June 26, in front of the Blazy Mall in Soldotna. The cuts were included in legislation passed by the U.S. Senate early Tuesday morning. (Photo by Jonas Oyoumick/Peninsula Clarion)
Ahead of Senate vote, Soldotna protesters defend Medicaid funding

Cuts to the program were included in legislation passed by the U.S. Senate early Tuesday morning.

Board President Zen Kelly speaks during a meeting of the Kenai Peninsula Borough School District’s Board of Education in Soldotna, Alaska, on Monday, Dec. 2, 2024. (Jake Dye/Peninsula Clarion)
Kenai Peninsula Borough school board to finalize budget

The new budget designed by the committee will be considered at a public hearing during the full board meeting on Monday evening.

Most Read