Global warming a killer to reefs?

[aquabeAnz]

Coral reefs around the world could expand in size by up to a third because of increased ocean warming, according to a new Australian study which contradicts the long-held belief that global warming is destroying the reefs.

Previous research has predicted a decline of between 20 and 60 percent in the size of coral reefs by 2100 relative to pre-industrial levels because of increasing carbon dioxide (CO2) levels caused by the greenhouse effect in ocean surface waters.

But the newly published research, by a team led by oceanographer Ben McNeil of Sydney's University of New South Wales, suggests that present coral reef calcification rates are not in decline and are equivalent to late 19th century levels.

"Our analysis suggests that ocean warming will foster considerably faster future rates of coral reef growth that will eventually exceed pre-industrial rates by as much as 35 percent by 2100," McNeil said in a statement Monday.

"Our finding stands in stark contrast to previous predictions that coral reef growth will suffer large, potentially catastrophic, decreases in the future."

The research has been published in the latest edition of the journal Geophysical Research Letters by McNeil and colleagues Richard Matear of the government's Commonwealth Scientific and Industrial Research Organisation (CSIRO) and David Barnes of the Australian Institute of Marine Science, at Townsville in north-eastern Australia.

Experts say seawater surface temperatures and the quantity of carbonate in seawater dictate the growth rate of coral reefs which are built from calcium carbonate when red algae cement together a framework of coral skeletons and sediments.

The Australian scientists have observed the calcification-temperature relationship at significant reef-building colonies around the world in the Indo-Pacific and at massive Porites reef colonies in Australia, Hawaii, Thailand, the Persian Gulf and the South Pacific island of New Ireland.

They say the predicted increase in the rate of coral reef calcification is most likely due to an enhancement in coral metabolism and/or increases in photosynthetic rates of red algae.

They used projections of ocean warming and CO2 concentration from a CSIRO climate model that accounts for atmosphere-ice and ocean carbon cycles.

A report released earlier this year by scientists at Queensland University found that the brightly-coloured corals that make up the world-renowned Great Barrier Reef, one of the world's natural wonders, would be largely dead by 2050 because of rising sea temperatures.

[lightningstrike]

sooner, if all nations do not abide by the kyoto protocol, the future generations (which could well be ur children or grandchildren) will suffer the effects of global warming, El Nino, etc.

[blueheaven]

Well as long as temperatures do not reach 30 degrees celcius in the reefs, its still ok but can how does global warming cause an increase in CO2 levels in the sea?

[Achilles Tang]

CO2 is a gas, a byproduct of industrialization & global warming and will dissolve in water, causing acidic water.... which means trouble for calcium carbonate... aka corals.

[blueheaven]

Oh I think I get it

More CO2 in the air=more concentrated=steeper concentration gradient=faster diffusion

Is this right?

[huanjie]

CO2 is release by industry when fossil fuels are burnt.

CO2 is belive to be the reason of global warming as it will trap heat in the atmosphere and causing the well-known "green house" effects.

I don't think coral reef would be threaten at all by the CO2 level, at the rate it goes, the coral would be given enough time to evolve .. some of these fellas survive the last ice age...

But the question is .....is the temperature really rising ?

The earth has been around for billions of years, the data collected is like catching a 2 seconds snap shots from a 2 hours movies , too little to model, too much assumption.....

I am more worried about human being as a species when the fossil fuels runs out and there is no replacement for it.

Maybe I am reading too much of the "state of fear" by micheal critchton...haha..