. 24/7 Space News .
ICE WORLD
Changing atmospheric conditions may contribute to stronger ocean waves in Antarctica
by Staff Writers
Fort Collins, CO (SPX) Jan 17, 2017


CSU researchers, including Rob Anthony (pictured), measured seismic signals generated by ocean waves in Antarctica. Image courtesy Rob Anthony, USGS.

Over the past few years, a large fracture has grown across a large floating ice shelf on the Antarctic Peninsula. The world is watching the ice shelf, now poised to break off an iceberg the size of Delaware into the ocean.

It's not a new phenomenon; this "thumb" of Antarctica, which juts out into the stormy Southern Ocean, has lost more than 28,000 square kilometers of floating ice - almost as large as Massachusetts - over the past half-century. This has included the complete disintegration of four ice shelves, the floating extensions of glaciers.

Now, a new study led by Colorado State University provides important details on the extent of sea ice, which can protect ice shelves from the impacts of ocean storms, in the Antarctic Peninsula.

El Nino-like weather patterns in Antarctica
Scientists have long thought that a shift in the Southern Annular Mode, which describes a large-scale pattern of atmospheric variability for the Southern Hemisphere similar to El Nino in the tropics, may produce conditions that can lead to the collapse of ice shelves.

The CSU-led research team offers important details on how the Southern Annular Mode affects storm activity and the extent of sea ice surrounding the Antarctic Peninsula. Sea ice may protect ice shelves from the impacts of ocean storms by weakening wave intensity before it reaches the coastline.

The researchers utilized a novel approach of studying long-term variations in seismic signals, called microseisms, generated by ocean waves in the region. The findings have implications for the wave environment of the Southern Ocean and, potentially, for factors driving the collapse of ice shelves, which can lead to an accelerated increase in global sea level.

More than two decades of data analyzed
Robert Anthony, who recently received a Ph.D. from CSU's Department of Geosciences and is now a Mendenhall Research Fellow at the U.S. Geological Survey's Albuquerque Seismological Laboratory, said that the team looked at 23 years of seismic data from Palmer Station on the Antarctic Peninsula and East Falkland Island near South America. They looked specifically at seismic signals generated by ocean waves.

"We were able to show that storm and ocean wave activity in the Drake Passage, the ocean basin between the Antarctic Peninsula and South America, increases during positive phases of the Southern Annular Mode, " he explained.

"We were also able to verify that sea ice cover does indeed impede ocean swell from reaching the coastline by showing which regions of sea ice impact the intensity of microseisms. This type of analysis may be useful for future applications of using seismic records to track the strength of sea ice over large regions, which has been difficult to determine from satellite observations."

Anthony, lead author of the study, said that based on the findings, the positive phase of the Southern Annular Mode may contribute to ice shelf weakening and potential collapse events by:

+ increasing air temperatures on the Antarctic Peninsula, which can enhance surface melting of ice shelves,

+ driving off sea ice, which enables ocean waves to directly impact ice shelves, and

+ generating stronger wave events.

Researchers had previously speculated on a link between ice shelf collapse and the Southern Annular Mode, based mainly on elevated air temperatures. But the CSU team now suspects that the reduction of sea ice and strong wave events in the Drake Passage could also play a role in rapid collapse events, such as the dramatic collapse of the Larsen A ice shelf in 1995 and, perhaps, the ongoing fracturing of the Larsen C ice shelf.

The team's next steps include looking more closely at specific ocean swell events and sea ice conditions during known ice shelf collapses and large iceberg calving events.

Research paper


Comment on this article using your Disqus, Facebook, Google or Twitter login.


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


.


Related Links
Colorado State University
Beyond the Ice Age






Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
ICE WORLD
Tracking Antarctic adaptations in diatoms
Washington DC (SPX) Jan 17, 2017
Diatoms are a common type of photosynthetic microorganism, found in many environments from marine to soil; in the oceans, they are responsible for more than a third of the global ocean carbon captured during photosynthesis. This leads to a significant amount of sequestered carbon ending up in the sediments at the bottom of the ocean. In both freshwater and marine ecosystems, the base of th ... read more


ICE WORLD
French, US astronauts install batteries outside space station

NASA to rely on Soyuz for ISS missions until 2019

'Hidden Figures' soars in second week atop box office

Lomonosov Moscow State University to Launch 'Space Department' in 2017

ICE WORLD
When One launch is not enough: SpaceX Return To Flight

2017 Rocket Campaign Begins in Alaska

Ruptured oxidant tank likely cause of Progress accident

Next Cygnus Mission to Station Set for March

ICE WORLD
Mars Rover Curiosity Examines Possible Mud Cracks

Opportunity Continues Its Journey South Along Crater Rim

New Year yields interesting bright soil for Opportunity rover

HI-SEAS Mission V crew preparing to enter Mars simulation habitat

ICE WORLD
China's first cargo spacecraft to leave factory

China launches commercial rocket mission Kuaizhou-1A

China Space Plan to Develop "Strength and Size"

Beijing's space program soars in 2016

ICE WORLD
Shaping the Future: Aerospace Works to Ensure an Informed Space Policy

Iridium-1 NEXT Launched on a Falcon 9

Russia-China Joint Space Studies Center May Be Created in Southeastern Russia

EchoStar 19 positioned in orbital slot

ICE WORLD
China's quantum communication satellite delivered for use

U.S. Army taps Leidos for training and simulation equipment

Thales supplying Crowsnest radar system to Royal Navy

Swiss air force upgrading surveillance radars

ICE WORLD
SF State astronomer searches for signs of life on Wolf 1061 exoplanet

Looking for life in all the right places with the right tool

Could dark streaks in Venusian clouds be microbial life

VLT to Search for Planets in Alpha Centauri System

ICE WORLD
Public to Choose Jupiter Picture Sites for NASA Juno

Pluto Global Color Map

Lowell Observatory to renovate Pluto discovery telescope

Flying observatory makes observations of Jupiter previously only possible from space









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.