The Reefgeneration Organization
For the Future of Coral Reefs
Coral Past, Present, and Future
Coral reefs provide habitat for marine critters, as well as food and storm protection for local people. Consequently, they are currently and have always been very important components of the ecosystem.
Coral reefs are under threat by greenhouse gas (carbon dioxide) emissions, which increase ocean acidity and temperature (see "reefs in danger" page). Both of these are detrimental to coral reefs.
Complicating predictions of future coral reef health is that greenhouse gases don't immediately change environmental conditions in the ocean. Circulation and other issues mean that there is a lag period between atmospheric dumping and effects on the ocean.
Simon Donner (University of British Columbia, Canada) has used computer models to ask whether or not coral reefs will withstand possible future shifts in world climate, taking into account this lag period, different predicted greenhouse gas emissions scenarios, as possible coral reef adaptation to increased ocean temperatures. He has concluded that atmospheric greenhouse gas levels may need to be reduced below what they are now to save coral reefs, unless they adapt naturally or through human intervention.​
A mathematical model was used to study how 9,000 coral reefs from around the world would respond to rising levels of carbon dioxide and increasing ocean acidity, Dr Silverman of the Carnegie Institution of Science in Washington told the American Association for the Advancement of Science in San Diego.
"A global map produced on the basis of these calculations shows that all coral reefs are expected to stop their growth and start to disintegrate when atmospheric CO2 reaches 560 parts per million – double its pre-industrial level – which is expected by the end of the 21st-century," he told the meeting.
Thus coral reef ecosystems may be severely reduced within less than 100 years.
According to fossil records, corals have existed for over 400 million years, and have evolved into modern reef building forms over the last 25 million years. Australia's great barrier reef, for example, is considered a younger reef, with newer portions being only 8,000 years old.
courses.knox.edu
Coral Reef Fossils
Coral Reef Ecosystem
Images showing the decrease in aragonite saturation levels in the ocean, and future predictions. Aragonite is a mineral consisting of calcium carbonate, which composes coral's hard structure.
theotherco2problem.wordpress.com