Friday, July 27, 2012

Deny This: Contested Himalayan Glaciers Really Are Melting, and Doing So at a Rapid Pace-Kind of Like Climate Change

Remember when climate change contrarians professed outrage over a few errors in the UN Intergovernmental Panel on Climate Change's last report? One of their favorite such mistakes involved an overestimation of the pace at which glaciers would melt at the "Third Pole," where the Indian subcontinent crashes into Asia. Some contrarians back in 2010 proceeded to deny that the glaciers of the Himalayas and associated mountain ranges were melting at all. But now, using satellites and on-the-ground surveys, scientists note that 82 glaciers in the Tibetan Plateau are retreating, 15 glaciers have dwindled in mass, and 7,090 glaciers have shrunk in size.

Why? The culprits include rising average temperatures characteristic of ongoing global warming and changes in precipitation, another sign of climate change, according to Lonnie Thompson of Ohio State University and his colleagues from the Chinese Academy of Sciences. The study appeared online in the journal Nature Climate Change on July 15 and is bad news for the hundreds of millions of people who rely on such glaciers to feed water into major rivers such as the Ganges, Mekong or Yangtze.

But climate contrarians have moved on, of course. This June, atmospheric scientist Richard Lindzen of the Massachusetts Institute of Technology, one of the only remaining climate contrarians actually trained in climate science, dismissed the documented 0.8 degree Celsius rise in average temperatures in the past 150 years or so as a small change during a talk at Sandia National Laboratory. Yet, that small change has resulted in events like chunks of ice double the size of Manhattan breaking free of the ancient Greenland ice sheet last week. Just a few years ago, an even bigger ice-massif crashed into the sea. Events that once happened every few decades in Greenland now happen every year or so.

That "small change" has also been enough for weird weather to play havoc around the world, whether it be the epic drought currently over-baking Midwestern corn crops or the torrents of rain unleashed this year on Beijing, killing at least 77 people, according to the Xinhua news agency. The list of weather-related disasters continues to get longer with each passing year and, while no single weather event can be tied directly to climate change, our continuing fossil-fuel burning loads the climate dice in favor of more and more snake-eye rolls such as deadly floods or searing droughts. It's all unfolding pretty much as predicted by climate scientists in the 1980s.

What's also unfolding pretty much as demanded by climate contrarians is a dearth of efforts to address the problem, maybe because we're all in denial. Global emissions of the greenhouse gases responsible for all this continue to grow, after taking a brief dip due to the Great Recession. Political and policy efforts to address the climate crisis, whether at the national or international level, seem spent (although there is some hope in efforts to buy time to combat climate change by cutting back on soot). Witness the climate talks in Durban, Cancun or Copenhagen. In the U.S. about the only leader still advocating for action to halt climate change is Bill McKibben, who has become somewhat of a climate Quixote, tilting for windmills and against the fossil fuel industry.

That industry, particularly titans such as ExxonMobil, has expressly achieved the goals laid out in an American Petroleum Institute memo from the 1990s recently reproduced in Steve Coll's book Private Empire:

- Average citizen "understands" (recognizes) uncertainties in climate science
- Recognition of uncertainties becomes part of the "conventional wisdom"
- Media "understands" (recognizes) uncertainties in climate science
- Media coverage reflects balance on climate science and recognition of the validity of viewpoints challenging current "conventional wisdom"
- Those promoting the Kyoto treaty [a global effort to reduce greenhouse gas emissions] on the basis of extant science appear to be out of touch with reality.

All five of those items on the list can be checked off. That's a big part of the reason why climate change has not featured as an issue in this year's U.S. presidential election.

What hope there is at present for addressing climate change in the U.S. lies in natural gas, dismissed as a nuisance for decades by the oil and coal industries. The "last fossil fuel," primarily the molecule known as methane, is itself a potent greenhouse gas. However, burning natural gas to generate electricity produces roughly half as much carbon dioxide the most ubiquitous greenhouse gas as burning coal does. Already, this year, burning natural gas accounts for as much electricity as burning coal for the first time in U.S. history, and its use has helped drop U.S. emissions by 430 million metric tons over the past five years, according to the International Energy Agency.

If fracking for shale gas can work for China too, global emissions could begin to drop (though it appears more likely at present that the U.S. will export highly polluting coal to China in greater quantities than any shale gas know-how). And if there's enough natural gas and there certainly is if we can learn to tap the methane molecules ensconced in icy cages throughout the world's oceans we might even use it to displace oil as the primary fuel for our cars and trucks.

At the same time, renewables, such as solar and wind, continue to grow by leaps and bounds, and nuclear power, though it may be moribund in the U.S., is gathering a renewed head of steam in countries such as China.

None of this will happen fast enough to reduce greenhouse gas emissions at a sufficiently dramatic pace to stop climate change. After all, burning natural gas still means more CO2 molecules in the atmosphere trapping heat. Cheap natural gas will also likely slow the race to develop and deploy alternative energy as well as the sprint (in geologic terms) to a global warming of more than 2 degrees Celsius. We're on track to achieve that over the next 40 years or so, with natural gas or without it.

That means that the people of 2100, or even 2500, will have us to blame if they don't like the weather. In the shorter term, we'll all have to learn to adapt to more sea level rise, weird weather, acidified oceans and other climate change impacts. The Earth is different now and will change even more fewer and fewer glaciers at the Third Pole, less ice at the North Pole and, who knows, a few hardy plants taking root in Antarctica for the first time in millennia. There's just no denying it.

Image: NASA Earth Observatory

Follow Scientific American on Twitter @SciAm and @SciamBlogs. Visit ScientificAmerican.com for the latest in science, health and technology news.
© 2012 ScientificAmerican.com. All rights reserved.




This article is brought to you by ONLINE DATING.

No comments:

Post a Comment