*NOAA on the 2005 bleaching event

I shouldn’t have been so paranoid. The NOAA site never went away; my googling skills must have slipped badly for a bit. The page is here, with chart and multiple maps. A more comprehensive report is promised once the quantitative data is tallied.

Requiem for a canary

The day this blog began, the AP carried an extensive story titled “Caribbean coral suffers record death“:

A one-two punch of bleaching from record hot water followed by disease has killed ancient and delicate coral in the biggest loss of reefs scientists have ever seen in Caribbean waters.

Researchers from around the globe are scrambling to figure out the extent of the loss. Early conservative estimates from Puerto Rico and the U.S. Virgin Islands find that about one-third of the coral in official monitoring sites has recently died.

The official reef monitoring sites are sufficiently widespread to justify confidence that at least one third of the coral in the Caribbean has died in just the past year. This is, quite simply, the most important news story of the decade. It was relegated to the inside pages of the few newspapers that carried it, and to the Science News ghetto of the major news media web pages.
What did it take to bring the Caribbean to this pass? A total of fourteen degree-days in which ocean temperatures exceeded the mean monthly maximum. (I learned this from a superb detail-laden map and discussion on the NOAA coral reef website; they seem to have been pulled since yesterday. In fact, today I could find no mention of the story at all on their pages.*) That was a statistically unusual excursion; but when temperatures warm another degree C, and even if not another gallon of gasoline were ever burned again, they are certain to warm that far, such excursions will not be unusual.

The simple fact is this: coral reefs in the Caribbean are doomed. One third of them died this year; the rest are as good as dead. (Most species of coral may well survive, of course, thanks to genetic variation and robustness of particular individuals; but it will be thousands of years before reefs like those of Jacques Cousteau’s day re-appear.) Since reefs are to the oceans what the Amazon rainforest is to the land – the mother lode of biological diversity – the next two decades will see numerous extinctions. Since reefs shelter many kinds of young organisms from predators until they come of age, the next two decades will see population crashes in a lot of species that do survive. And that in turn will threaten the existence of top level predators, the sorts of fish we humans love to eat.

We have effectively killed a small ocean. The deed is done, the mortal blow has been struck. The time when we could have taken effective action to prevent it was ten or fifteen years ago, and all we can do now is stand around the ICU murmuring condolences until it flatlines. Larger oceans hang in the balance. Is it already too late for them as well? Perhaps it isn’t. But it certainly is, unless all of us begin to change our way of living immediately.

By itself, the news is devastating, a catastrophe a little slower but far more severe than Pearl Harbor, or 9/11, or Katrina. But it carries a lesson: when the bills for ignoring global warming finally fall due, they may arrive with breathtaking swiftness. Climate systems, ocean systems, and biological systems all partake of nonlinear dynamics. That is to say, they are subject to equations in which a small change may lead to a small result; but the next small change can lead to sweeping consequences. There are no guarantees that outputs will remain proportional to inputs.

The news from the reefs is the second major story in two months to indicate that “climate change” is entering a nonlinear phase. In mid-February, we learned that the Greenland ice sheets are accelerating, flowing and melting into the North Atlantic at twice the speed they had clocked just a decade ago. See Real Climate (which I am adding to Tinsel Wing’s permanent link list) for the best in continuing discussion of global warming from actual climatologists.

We all live in this coal mine, and we have no means of leaving it. The canary just died. It’s a long, long way to the sweet air of the surface.

Brothers and sisters, let’s dig.