Climate change suspended coral reef growth for 2,500 years

Jul 05, 2012
Coral Reefs

Climate change drove coral reefs to a total ecosystem collapse lasting thousands of years, according to a paper published this week in Science. The paper shows how natural climatic shifts stopped reef growth in the eastern Pacific for 2,500 years. The reef shutdown, which began 4,000 years ago, corresponds to a period of dramatic swings in the El Niño–Southern Oscillation (ENSO). "As humans continue to pump greenhouse gases into the atmosphere, the climate is once again on the threshold of a new regime, with dire consequences for reef ecosystems unless we get control of climate change," said coauthor Richard Aronson, a biology professor at Florida Institute of Technology.

Doctoral student Lauren Toth and Aronson, her adviser at Florida Tech, led the study of how past episodes of climate change influenced tropical reefs of the eastern Pacific. Toth, Aronson and a multi-institutional research team drove 17-foot, small-bore aluminum pipes deep into the dead frameworks of coral reefs along the Pacific coast of Panama and pulled out cross-sections of the reefs. By analyzing the corals in the cores, they were able to reconstruct the history of the reefs over the past 6,000 years.

"We were shocked to find that 2,500 years of reef growth were missing from the frameworks," said Toth. "That gap represents the collapse of reef ecosystems for 40 percent of their total history." When Toth and Aronson examined reef records from other studies across the Pacific, they discovered the same gap in reefs as far away as Australia and Japan.

Toth linked the coral-reef collapse to changes in ENSO. ENSO is the climate cycle responsible for the weather conditions every few years known as El Niño and La Niña events. The timing of the shutdown in reef growth corresponds to a period of wild swings in ENSO. "Coral reefs are resilient ecosystems," said Toth. "For Pacific reefs to have collapsed for such a long time and over such a large geographic scale, they must have experienced a major climatic disturbance. That disturbance was an intensified ENSO regime."

Scenarios of climate change for the coming century echo the climate patterns that collapsed reefs in the eastern Pacific 4,000 years ago. The reefs off Panama are on the verge of another collapse. "Climate change could again destroy coral-reef ecosystems, but this time the root cause would be the human assault on the environment and the collapse could be longer-lasting," said Aronson. "Local issues like pollution and overfishing are major destructive forces and they need to be stopped, but they are trumped by climate change, which right now is the greatest threat to ."

Toth noted more hopefully that reefs have proven resilient in the past, so the potential for recovery should be good if can be mitigated or reversed.

Explore further: US delays decision on Keystone pipeline project

More information: "ENSO Drove 2500-Year Collapse of Eastern Pacific Coral Reefs," by L.T. Toth; R.B. Aronson; et al., Science, 2012.

Related Stories

Climate will damage reefs at 'different rates'

Jul 22, 2011

(PhysOrg.com) -- Climate change and acidifying ocean water are likely to have a highly variable impact on the world's coral reefs in space, time and diversity, according to an international team of coral scientists, ...

Ongoing collapse of coral reef shark populations

Dec 04, 2006

Investigators have revealed that coral reef shark populations are in the midst of rapid decline, and that "no-take zones" -- reefs where fishing is prohibited -- do protect sharks, but only when compliance with no-take regulations ...

Recommended for you

US delays decision on Keystone pipeline project

Apr 18, 2014

The United States announced Friday a fresh delay on a final decision regarding a controversial Canada to US oil pipeline, saying more time was needed to carry out a review.

New research on Earth's carbon budget

Apr 18, 2014

(Phys.org) —Results from a research project involving scientists from the Desert Research Institute have generated new findings surrounding some of the unknowns of changes in climate and the degree to which ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

tadchem
3 / 5 (2) Jul 05, 2012
Were they able to trace the history of ocean acidity over that interval?
NotParker
2.6 / 5 (5) Jul 05, 2012
4,000 years ago ....

Minoan Warming
Roman Warming
Medieval Warming

http://jonova.s3....-new.png

All natural. All warmer than today.

More news stories

China says massive area of its soil polluted

A huge area of China's soil covering more than twice the size of Spain is estimated to be polluted, the government said Thursday, announcing findings of a survey previously kept secret.

UN weather agency warns of 'El Nino' this year

The UN weather agency Tuesday warned there was a good chance of an "El Nino" climate phenomenon in the Pacific Ocean this year, bringing droughts and heavy rainfall to the rest of the world.

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Ex-Apple chief plans mobile phone for India

Former Apple chief executive John Sculley, whose marketing skills helped bring the personal computer to desktops worldwide, says he plans to launch a mobile phone in India to exploit its still largely untapped ...

Filipino tests negative for Middle East virus

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...