The coral is dying, the Great Lakes are heating up

Speaking of those natural indicators of climate change I mentioned in my review of Henry Pollack’s A World Without Ice, we have two more examples:

Coral reefs suffer mass bleaching:

High ocean temperatures this year are being blamed for the bleaching, which experts fear could be worse than a similar event in 1998 which saw an estimated 16 per cent of the world’s reefs being destroyed.

Dr Mark Eakin, coordinator of the National Oceanic and Atmospheric Administration’s Coral Reef Watch, said: “The bleaching is very strong throughout south east Asia and the central Indian Ocean.

“The reports are that it is the worst since 1997/1998. This is a really huge event and we are going to see a lot of corals dying.”

Coral reefs provide refuge and food to nearly a quarter of all marine species, making them among the most biologically diverse habitats on the planet. Bleaching can also rob fish and other species of important shelter and food sources.

Although reefs can often recover from bleaching, it leaves the coral vulnerable to damage from storms, infections and other environmental stress, increasing the risk of deaths.

Coral reef monitoring teams have reported mass bleaching of coral reefs off the coast of Thailand, Malaysia, Vietnam, Cambodia and Indonesia while the Maldives, Sri Lanka and reefs off the coast of east Africa have also been hit.

With ocean temperatures reaching record levels and combined with the end of an El Nino episode, scientists fear there could be even more damage to corals as the year continues.

Scientists in Thailand have reported reefs suffering 90% of their corals being bleached and up to 20% of the corals dead.

Olivia Durkin, who is leading the bleaching monitoring at the Centre for Biodiversity in Peninsular Thailand, said: “This year’s severe coral bleaching has the potential to be the worst on record.

“Extensive bleaching, death and disease are reported not only in corals, but giant clams, sea anemones and soft corals are also losing their symbiotic algae.”

…

Research published on Friday in the journal Science showed that coral growth in the Red Sea has declined by a third over the past 12 years due to rising temperatures and warned that coral there would cease growing entirely by 2070 if warming continues.

Volunteers in Cambodia say this year they have seen bleaching of 90% to 100% of the shallow water reefs around the country’s coast Koh Rong and Koh rong Semleon Islands after water temperatures rose by 3 degrees.

Half of the reefs off Weh, in Indonesia have seen 80% of their corals bleached.

Lake Superior, a Huge Natural Climate Change Gauge, Is Running a Fever (emphasis added):

As the world’s largest freshwater system warms, it is poised to systematically alter life for local wildlife and the tribes that depend on it, according to regional experts. And the warming could also provide a glimpse of what is happening on a more global level, they say.

“The Great Lakes in a lot of ways have always been a canary in the coal mine,” Cameron Davis, the senior adviser to the U.S. EPA on the Great Lakes, said last week. “Not just for the region or this country, but for the rest of the world.”

And it seems the canary’s song is growing ever more halting.

Lake Superior, which is the largest, deepest and coldest of the five lakes, is serving as the “canary for the canary,” Davis said at a public meeting of the Interagency Climate Change Adaptation Task Force last week, pointing to recent data trends.

Total ice cover on the lake has shrunk by about 20 percent over the past 37 years, he said. Though the change has made for longer, warmer summers, it’s a problem because ice is crucial for keeping water from evaporating and it regulates the natural cycles of the Great Lakes.

But the warming shows no sign of abatement. This year, the waters in Lake Superior are on track to reach — and potentially exceed — the lake’s record-high temperatures of 68 degrees Fahrenheit, which occurred in 1998.

Analysis of several buoys that measure temperatures in the lake reveal that the waters are some 15 degrees warmer than they would normally be at this time of year, Jay Austin, a professor of physics at the University of Minnesota, Duluth’s Large Lakes Observatory, said in a recent interview.

His analysis of National Oceanic and Atmospheric Administration data indicates that summer for the lake, which happens at about a 40-degree threshold, came about a month early this year.