Featured Research

from universities, journals, and other organizations

Dramatic climate swings likely as world warms: Ancient El Niño clue to future floods

Date:
July 15, 2011
Source:
University of Oxford
Summary:
Dramatic climate swings behind both last year's Pakistan flooding and this year's Queensland floods in Australia are likely to continue as the world gets warmer, scientists predict. Researchers have discovered that the El Niño Southern Oscillation (ENSO), the sloshing of the warmest waters on the planet from the West Pacific towards the East Pacific every 2-7 years, continued during Earth's last great warm period, the Pliocene. Their results suggest that swings between the two climatic extremes, known as El Niño and La Niña, may even have occurred more frequently in the warmer past and may increase in frequency in the future.

Flooded road in Queensland, Australia.
Credit: © Johan Larson / Fotolia

Dramatic climate swings behind both last year's Pakistan flooding and this year's Queensland floods in Australia are likely to continue as the world gets warmer, scientists predict.

Researchers at the Universities of Oxford and Leeds have discovered that the El Niño Southern Oscillation (ENSO), the sloshing of the warmest waters on the planet from the West Pacific towards the East Pacific every 2-7 years, continued during Earth's last great warm period, the Pliocene.

Their results suggest that swings between the two climatic extremes, known as El Niño and La Niña, may even have occurred more frequently in the warmer past and may increase in frequency in the future. Extreme ENSO events cause droughts, forest fires and floods across much of the world as well as affecting fishery production.

Reporting in the journal Paleoceanography, the team of geochemists and climate modellers use the Pliocene as a past analogue and predictor of the workings of Earth's future climate.

The Pliocene (which lasted from 5 to 3 million years ago) had carbon dioxide levels similar to the present day, with global mean temperatures about 2-3ºC higher, so it is a useful test-ground for climate research.

Lead Scientist Nick Scroxton from Oxford University's Department of Earth Sciences said: 'We know from previous studies that the mean state of the Pacific during the warm Pliocene was similar to the climate patterns observed during a typical El Niño event that we see today.

'However, until recently it was believed that a warmer Pacific would reduce the climate swings that cause the dramatic weather extremes throughout the region leading to a permanent state of El Niño. What we didn't expect was that climatic variability would remain strong under these warmer conditions.'

The team combined experiments performed on the Met Office Hadley Centre climate model, HadCM3, with the analysis of the chemical composition of lots of individual shells of small organisms, known as foraminifera.

These were collected from a deep sea sediment core in the East Equatorial Pacific, and provided a record of temperature in the upper layer of the ocean through time. They discovered that the range of temperatures experienced by these organisms during the Pliocene, was higher than what would be expected from just the seasonal cycle.

The extra variation in temperature can be explained by the additional extreme temperature swings provided by the El Niño/La Niña system.

The authors say the agreement in findings from both ocean data and modelling leaves little doubt that ENSO will persist in a warmer world. Earlier this year a team from Japan studying corals from the same period showed climatic variability in the western Pacific on a similar scale to today, questioning the idea of a permanent El Niño during the Pliocene.

This new study goes further, showing that the oscillation is Pacific-wide, and is likely to be caused by the El Niño/La Niña. This suggests that our warmer future will continue to be dogged, maybe even more regularly, by extreme climatic events.


Story Source:

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


Journal Reference:

  1. N. Scroxton, S. G. Bonham, R. E. M. Rickaby, S. H. F. Lawrence, M. Hermoso, A. M. Haywood. Persistent El Niño–Southern Oscillation variation during the Pliocene Epoch. Paleoceanography, 2011; 26 (2) DOI: 10.1029/2010PA002097

Cite This Page:

University of Oxford. "Dramatic climate swings likely as world warms: Ancient El Niño clue to future floods." ScienceDaily. ScienceDaily, 15 July 2011. <www.sciencedaily.com/releases/2011/07/110714103249.htm>.
University of Oxford. (2011, July 15). Dramatic climate swings likely as world warms: Ancient El Niño clue to future floods. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2011/07/110714103249.htm
University of Oxford. "Dramatic climate swings likely as world warms: Ancient El Niño clue to future floods." ScienceDaily. www.sciencedaily.com/releases/2011/07/110714103249.htm (accessed October 20, 2014).

Share This



More Earth & Climate News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) — He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

3BL Media (Oct. 20, 2014) — Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-fuel Impala Video provided by 3BL
Powered by NewsLook.com
White Rhino's Death In Kenya Means Just 6 Are Left

White Rhino's Death In Kenya Means Just 6 Are Left

Newsy (Oct. 20, 2014) — Suni, a rare northern white rhino at Ol Pejeta Conservancy, died Friday. This, as many media have pointed out, leaves people fearing extinction. Video provided by Newsy
Powered by NewsLook.com
Beijing Marathon Runners Brave Hazardous Air Pollution

Beijing Marathon Runners Brave Hazardous Air Pollution

AFP (Oct. 19, 2014) — Tens of thousands of runners battled thick smog at the Beijing Marathon on Sunday, with some donning masks as the levels of PM2.5 small pollutant particles soared to 16 times the maximum recommended level. Duration: 00:54 Video provided by AFP
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:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

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