Another climate impact comes faster than predicted
Energy companies remove the tops of entire mountains. Now it turns out humanity’s use of that coal is removing the tops of entire glaciers.
Climate models have repeatedly underestimated the speed and scale of major climate change impacts (see list below). That is why climate scientists — and indeed everyone but the blinkered deniers — are increasingly desperate that the we cut emissions sharply and quickly.
A major new study by leading international cryosphere scientists, including American’s own
rock ice star, Lonnie Thompson, “Mass loss on Himalayan glacier endangers water resources” ($ub. req’d), finds yet another key impact occurring faster than predicted — the melting of the Naimona’nyi Glacier in the Himalaya (Tibet). The study concludes ominously:
If Naimona’nyi is characteristic of other glaciers in the region, alpine glacier meltwater surpluses are likely to shrink much faster than currently predicted with substantial consequences for approximately half a billion people.
The study notes that Naimona’nyi is the highest glacier (6 kilometers above sea level) “documented to be losing mass annually.” MSNBC reports:
Lonnie Thompson of Ohio State University and a team of researchers traveled to central Himalayas in 2006 to study the Naimona’nyi glacier, expecting to find some melting … But when the team analyzed samples of glacier, what they found stunned them.
The glacier was being literally decapitated like a West Virginia coal mountain:
Glaciers around the planet are usually dated by looking for two pulses of radioactivity buried in the ice. These are the leftovers from American and Russian atomic bomb testing in the 1950’s and 1960’s.
In the Naimona’nyi samples, there was no sign of the tests. In fact, the glacier had melted so much that the exposed surface of the glacier dated to 1944.
“We were very surprised not to find the 1962-1963 horizon, and even more surprised not to find the 1951-1952 signal,” Thompson said. In more than twenty years of sampling glaciers all over the world, this was the first time both markers were missing …
“At the highest elevations, we’re seeing something like an average of 0.3 degrees Centigrade warming per decade,” Thompson said. “The Intergovernmental Panel on Climate Change (IPCC) projects 3 degrees of warming by 2100. But that’s at the surface; up at the elevations where these glaciers are there could be almost twice as much, almost 6 degrees.”
Lonnie, Lonnie, Lonnie. The IPCC does not project 3Â°C of warming by 2100. It projects a range of warming that depends primarily on whether and how fast humanity reduces projected emissions. On the current path of unrestricted emissions — a rate of increase in CO2 faster than even the most pessimistic IPCC scenario — the IPCC projects total warming at the surface would likely exceed 5Â°. And that, of course, assumes the IPCC models don’t in general underestimate future impacts, which all evidence suggests that they do. But I digress.
“I have not seen much as compelling as this to demonstrate how some glaciers are just being decapitated,” Shawn Marshall of the University of Calgary said …
Marshall, who studies glaciers in North America, said it’s striking how much worse glaciers near the equator are than those in the Canadian Rocky and Cascade mountain ranges.
The finding has ominous implications for the hundreds of millions of people who depend on the waters of the Naimona’nyi and other glaciers for their livelihoods. Across the region, no one know just how much water the Himalayas have left, but Thompson said it’s dwindling fast.
“You can think of glaciers kind of like water towers, ” he said. “They collect water from the monsoon in the wet season, and release it in the dry season. But how effective they are depends on how much water is in the towers.”
“The science is beyond dispute … Delay is no longer an option. Denial is no longer an acceptable response.”
Other climate impacts happening faster than the models had projected:
- “The recent [Arctic] sea-ice retreat is larger than in any of the (19) IPCC [climate] models” [PDF] — and that was a Norwegian expert in 2005. The retreat has accelerated in the past two years.
- The ice sheets appear to be shrinking “100 years ahead of schedule.” That was Penn State climatologist Richard Alley in March 2006. In 2001, the IPCC thought that neither Greenland nor Antarctica would lose significant mass by 2100. They both already are.
- Sea-level rise from 1993 and 2006 — 3.3 millimetres per year as measured by satellites — was higher than the IPCC climate models predicted.
- The ocean carbon sink is saturating sooner than expected.
- The subtropics are expanding faster than the models project.