Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search

 


Coral bands reflect Pacific Ocean 20-30 year climate swings

MEDIA RELEASE

Coral bands reflect Pacific Ocean 20-30 year climate swings

13 January 2014

University of Queensland researchers have found physical evidence in Great Barrier Reef corals of a little-known, long-term climate pattern in the Pacific Ocean.

The Pacific Decadal Oscillation –discovered and named only in the 1990s – describes phases of warm and cool sea surface temperatures that alternate between the Pacific Ocean’s east and west, usually over periods of 20 to 30 years.

Lead researcher Dr Alberto Rodriguez-Ramirez, of UQ’s School of Earth Sciences, said the team shone ultraviolet light on longitudinal sections of coral colonies to see their luminescent “growth bands”, and found a record of flood plumes from central Queensland’s Fitzroy River at times coinciding with the Pacific Decadal Oscillation pattern over the past century.

“We have demonstrated that this oscillation pattern is a key driver of river runoff impacting on the Great Barrier Reef,” Dr Rodriguez-Ramirez said.

“Our study suggests that this oscillation will influence the frequency and intensity of future extreme events such as floods – as well as ecological processes – in the region.”

Co-author Professor Jian-xin Zhao, also from UQ’s School of Earth Sciences, said it was well understood that shorter-term phenomenon such as El Niño and La Niña influenced climate in the southern Great Barrier Reef.

“But this work shows that the region also feels the effects of the slower-moving Pacific Decadal Oscillation,” Professor Zhao said.

“This is a significant advance in our understanding of climate variability.”

Co-author Professor John Pandolfi, from UQ’s School of Biological Sciences, said the study examined century-old coral colonies – “bommies” – around the Keppel Islands, 50km from the Fitzroy River mouth.

“As a result of this research, we now know that corals from this area have great potential for reconstructing even longer-term historical evolution of the Pacific Decadal Oscillation,” Professor Pandolfi said.

“Some bommies are five to six metres tall and 400 years old. They can provide us with much longer-term information than is available from satellite-based data, which goes back only 40-50 years.

“This will help refine future models for predicting this important climate phenomenon.”

Dr Rodriguez-Ramirez said that although floods were not new in the region, increased human activity in the Fitzroy catchment since the mid-20th century had increased the impact of extreme weather events on reef ecosystems.

“Our findings are timely, given that extreme weather conditions – associated with La Niña and a ‘negative’ Pacific Decadal Oscillation phase – caused severe negative impacts on human populations along the east coast of Australia in 2011 and 2013,” he said.

After work by other scientists in the 1990s, it is generally understood that a “negative” or “cool” phase occurs when the east Pacific Ocean surface cools and the west warms.

A “positive” or “warm” phase occurs when the pattern reverses.

Like the growth rings found in tree trunks that give year-by-year records of climate and environmental conditions during the tree’s life, longitudinal slices from corals provide a similarly accurate environmental record when viewed under ultraviolet light.

This study produced the first coral core evidence of the massive 2011 floods.

The research was published last week in PLOS ONE, a peer-reviewed, open-access resource produced by the Public Library of Science.

Researchers from NIOZ Royal Netherlands Institute for Sea Research and The University of Western Australia’s Oceans Institute/School of Earth and Environment also worked on the research.

Funding for the project came from the Marine and Tropical Science Research Facility, the NERP Tropical Ecosystems Hub, as well as from the Australian Research Council Discovery Projects scheme, the Endeavour International Postgraduate Research Scholarship scheme, the UQ Living Allowance Scholarship, the UQ Graduate School International Travel Award, and the PADI Foundation.


© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

Maritime: Navigation Safety Review Raises Big Issues For The Govt

Shipping Federation: "The reports makes it clear that the ratification of the Maritime Labour convention (MLC) is long overdue. Only when the MLC is ratified will Maritime NZ be able to inspect and enforce the labour conditions on international ships visiting our ports." More>>

ALSO:

100 Years After Einstein Prediction: Gravitational Waves Found

For the first time, scientists have observed ripples in the fabric of spacetime called gravitational waves, arriving at the earth from a cataclysmic event in the distant universe. This confirms a major prediction of Albert Einstein’s 1915 general theory of relativity and opens an unprecedented new window onto the cosmos. More>>

ALSO:

Farming: Alliance Plans To Start Docking Farmer Payments

Alliance Group, New Zealand's second-largest meat cooperative, plans to start withholding some stock payments to its farmers from next week to bolster its balance sheet and force suppliers to meet their share requirements. More>>

ALSO:

Gambling: SkyCity First Half Profit Rises 30%, Helped By High Rollers

SkyCity anticipates the Auckland business will benefit from government gaming concessions which were triggered on Nov. 11 in recognition of SkyCity’s $470 million Convention Centre development. Morrison said the concessions would allow the Auckland business to lift its activity during peak period, noting it had a record revenue week over the Christmas and New Year period. More>>

ALSO:

Money For Light: Kiwi Scientists Secure Preferential Access To Synchrotron

Science and Innovation Minister Steven Joyce today announced a three-year investment of $2.8 million in the Australian Synchrotron, the largest piece of scientific infrastructure in the Southern Hemisphere, to secure preferential access for Kiwi scientists. More>>

Telco Industry Report: Investment Hits $1.7 Bln A Year

Investment in the telecommunications sector is $1.7 billion a year, proportionately one of the highest levels in the OECD, according to a report released today on the status of the New Zealand sector. More>>

ALSO:

PGPs: New Programme Sets Sights On Strong Wool

A new collaboration between The New Zealand Merino Company (NZM) and the Ministry for Primary Industries (MPI), announced today, aims to deliver premiums for New Zealand's strong wool sector... More>>

ALSO:

Get More From Scoop

 
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news