Nav: Home

Warming waters in western tropical Pacific may affect West Antarctic Ice Sheet

June 13, 2019

Warming waters in the western tropical Pacific Ocean have significantly increased thunderstorms and rainfall, which may affect the stability of the West Antarctic Ice Sheet and global sea-level rise, according to a Rutgers University-New Brunswick study.

Since the mid-1990s, West Antarctica - a massive ice sheet that sits on land - has been melting and contributing to global sea-level rise. That melting has accelerated this century. Wind and weather patterns play a crucial role in governing the melting: Winds push warm ocean water toward the ice sheet and melt it from below, at the same time as winds bring warm air over the ice sheet surface and melt it from above.

The study, in the journal Geophysical Research Letters, found that the South Pacific Convergence Zone, a region of the western tropical Pacific, is a major driver of weather variability across West Antarctica.

"With so much at stake - in coastal communities around the globe, including in New Jersey - it is very important to understand the drivers of weather variability in West Antarctica," said Kyle Clem, a former post-doc who led the research at Rutgers-New Brunswick and is now at Victoria University of Wellington in New Zealand. "Knowing how all regions of the tropics influence West Antarctica, both independently and collectively, will help us understand past climate variability there and perhaps help us predict the future state of the ice sheet and its potential contribution to global sea-level rise."

Rutgers researchers studied how warming ocean temperatures in the western tropical Pacific influence weather patterns around West Antarctica. This century, the Antarctic Peninsula and interior West Antarctica have been cooling while the Ross Ice Shelf has been warming - a reversal of what happened in the second half of the 20th century. From the 1950s to the 1990s, the Antarctic Peninsula and interior West Antarctica were the most rapidly warming regions on the planet, and the Ross Ice Shelf was cooling.

The temperature trends flipped at the start of this century. Coinciding with the flip in West Antarctic temperature trends, ocean temperatures in the western tropical Pacific began warming rapidly. Using a climate model, the researchers found that warming ocean temperatures in the western tropical Pacific have resulted in a significant increase in thunderstorm activity, rainfall and convection in the South Pacific Convergence Zone. Convection in the atmosphere is when heat and moisture move up or down.

A rainfall increase in the zone results in cold southerly winds over the Antarctic Peninsula and warm northerly winds over the Ross Ice Shelf, consistent with the recent cooling and warming in those respective regions. So the West Antarctic climate, although isolated from much of the planet, is profoundly influenced by the tropics. The findings may help scientists interpret the past West Antarctic climate as recorded in ice cores.
-end-
Study co-authors include Benjamin R. Lintner, an associate professor in the Department of Environmental Sciences; Anthony J. Broccoli, a professor who chairs that department; and James R. Miller, a professor in the Department of Marine and Coastal Sciences in the School of Environmental and Biological Sciences.

Rutgers University

Related Ice Sheet Articles:

Thousands of meltwater lakes mapped on the east Antarctic ice sheet
The number of meltwater lakes on the surface of the East Antarctic Ice Sheet is more significant than previously thought, according to new research.
Researchers discover ice is sliding toward edges off Greenland Ice Sheet
They found that ice slides over the bedrock much more than previous theories predicted of how ice on the Greenland Ice Sheet moves.
A clearer picture of global ice sheet mass
Fluctuations in the masses of the world's largest ice sheets carry important consequences for future sea level rise, but understanding the complicated interplay of atmospheric conditions, snowfall input and melting processes has never been easy to measure due to the sheer size and remoteness inherent to glacial landscapes.
Researchers discover more than 50 lakes beneath the Greenland Ice Sheet
Researchers have discovered 56 previously uncharted subglacial lakes beneath the Greenland Ice Sheet bringing the total known number of lakes to 60.
Ice-sheet variability during the last ice age from the perspective of marine sediment
By using marine sediment cores from Northwestern Australia, a Japanese team led by National Institute of Polar Research (NIPR) and the University of Tokyo revealed that the global ice sheet during the last ice age had changed in shorter time scale than previously thought.
Novel hypothesis goes underground to predict future of Greenland ice sheet
The Greenland ice sheet melted a little more easily in the past than it does today because of geological changes, and most of Greenland's ice can be saved from melting if warming is controlled, says a team of Penn State researchers.
Greenland's southwest ice sheet particularly sensitive to warming
The ice fields of southwest Greenland are becoming particularly sensitive to a climate cycle called the North Atlantic Oscillation as global warming proceeds.
Antarctic ice sheet could suffer a one-two climate punch
Variations in the axial tilt of the Earth have significant implications for the rise and fall of the Antarctic Ice Sheet, the miles-deep blanket of ice that locks up huge volumes of water that, if melted, would dramatically elevate sea level and alter the world's coastlines.
The first impact crater found underneath the Greenland ice sheet
A 31-kilometer-wide impact crater underneath about a kilometer of the Hiawatha Glacier's ice is the first of its kind to be discovered in northwest Greenland, scientists report.
Moderate warming could melt East Antarctic Ice Sheet
Parts of the world's largest ice sheet would melt if Antarctic warming of just 2°C is sustained for millennia, according to international research.
More Ice Sheet News and Ice Sheet Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#538 Nobels and Astrophysics
This week we start with this year's physics Nobel Prize awarded to Jim Peebles, Michel Mayor, and Didier Queloz and finish with a discussion of the Nobel Prizes as a way to award and highlight important science. Are they still relevant? When science breakthroughs are built on the backs of hundreds -- and sometimes thousands -- of people's hard work, how do you pick just three to highlight? Join host Rachelle Saunders and astrophysicist, author, and science communicator Ethan Siegel for their chat about astrophysics and Nobel Prizes.