Featured Research

from universities, journals, and other organizations

Circulation changes in a warmer ocean

Date:
February 22, 2013
Source:
Uni Research
Summary:
In a new study, scientists suggest that the pattern of ocean circulation was radically altered in the past when climates were warmer.

Simulated changes in sea surface temperature (oC, contours) with comparison to reconstructed changes (circles) in the North Atlantic.
Credit: Image courtesy of Uni Research

In a new study, scientists suggest that the pattern of ocean circulation was radically altered in the past when climates were warmer.

Ancient warm periods offer useful insights into potential future warming and its impacts. The mid-Pliocene, ~3 million years ago, was a relatively recent period of global warmth that is often considered as an analog for our future.

During this warm period, unusually warm surface conditions existed in the North Atlantic, which has often been simply explained by the intensification of the existing pattern of ocean circulation. However, reproducing these changes with climate models has eluded researchers for more than a decade -- suggesting either that there was something wrong with the long-standing explanation or with the models used to predict the behavior of warmer oceans.

An alternative pattern of warm ocean circulation

A team of Bergen scientists reevaluated the existing observations and used the Norwegian Earth System model (NorESM) to carry out simulations to better understand ocean circulation during the warm mid-Pliocene.

They illustrated that the largest changes occurred in the deep Southern Ocean, but not in the North Atlantic, indicating that the existing explanation was not adequate. They found that the data and simulations pointed toward an altogether different pattern of ocean circulation, with Antarctic waters playing a stronger role due to faster renewal of the deeper water masses in the Southern Ocean during the mid-Pliocene. This alternative explanation provided a solution to the long standing discrepancy between reconstructions of ocean circulation at the time and available model simulations.

North Atlantic warming

The team also addressed the unusual warmth in the North Atlantic during the warm mid-Pliocene. The observed high latitude warmth was shown not to require the intensification of todays ocean circulation and the transport of ocean heat to the north, rather it was a direct response to changes in insolation and atmospheric carbon dioxide levels at the time. The study highlights just how differently ocean circulation was when the planet was warmer and carbon dioxide levels were high.

The study by Zhongshi Zhang, Kerim Nisancioglu and Ulysses Ninnemann from the Bjerknes Centre for Climate Research in Bergen was published Feb. 19 in Nature Communications.


Story Source:

The above story is based on materials provided by Uni Research. Note: Materials may be edited for content and length.


Journal Reference:

  1. Zhongshi Zhang, Kerim H. Nisancioglu, Ulysses S. Ninnemann. Increased ventilation of Antarctic deep water during the warm mid-Pliocene. Nature Communications, 2013; 4: 1499 DOI: 10.1038/ncomms2521

Cite This Page:

Uni Research. "Circulation changes in a warmer ocean." ScienceDaily. ScienceDaily, 22 February 2013. <www.sciencedaily.com/releases/2013/02/130222083023.htm>.
Uni Research. (2013, February 22). Circulation changes in a warmer ocean. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2013/02/130222083023.htm
Uni Research. "Circulation changes in a warmer ocean." ScienceDaily. www.sciencedaily.com/releases/2013/02/130222083023.htm (accessed July 31, 2014).

Share This




More Earth & Climate News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Big Waves In Arctic Ocean Threaten Polar Ice

Big Waves In Arctic Ocean Threaten Polar Ice

Newsy (July 30, 2014) — Big waves in parts of the Arctic Ocean are unprecedented, mainly because they used to be covered in ice. Video provided by Newsy
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) — Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com
Amid Drought, UCLA Sees Only Water

Amid Drought, UCLA Sees Only Water

AP (July 30, 2014) — A ruptured 93-year-old water main left the UCLA campus awash in 8 million gallons of water in the middle of California's worst drought in decades. (July 30) Video provided by AP
Powered by NewsLook.com
In Virginia, the Rise of a New Space Coast

In Virginia, the Rise of a New Space Coast

AP (July 30, 2014) — Every summer, tourists make the pilgrimage to Chincoteague Island, Va. to see wild ponies cross the Assateague Channel. But, it's the rockets sending to supplies to the International Space Station that are making this a year-round destination. (July 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



      Save/Print:
      Share:  

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile iPhone Android Web
      Follow Facebook Twitter Google+
      Subscribe RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins