Global warming unequivocal in its advance, says NCAA expert

record year for glacier melting in Greenland, as observed by satellite.”

With some exceptions, he said, glaciers are melting substantially around the globe. “Since the 1960s,” he said, “ocean heat content, humidity, temperatures near just above the sea surfaces and the temperatures over land and oceans have increased substantially. Meanwhile, snow cover, glaciers and sea ice have decreased.”

As for what is causing the changes shown by his graphs, he said, “Natural variations [used in models] do not explain climatic change. Climate model simulations with just natural ‘forcing,’ including volcanic and solar, do not reproduce warming. However, when the increase in greenhouse gases is included, models do reproduce the global warming patterns. We consider this a ‘smoking gun’ proof.”

Adding the effects of aerosols to climate models further improves their agreement with the temperature-warming trends of the last decades, he said.

Slow computing initially handicapped experiments to simulate climate change, he said. Much faster computing speeds have led to more accurate models.

Still, Washington said, international meetings about climate with politicians in Copenhagen, Cancun, Mexico, and Durban, South Africa, “haven’t gotten very far. Basically, there’s a lot of inertia in making big changes in our energy profile.”

He postulated several reasons for this. “Many skeptics claim that climate change is a hoax and we have some sort of secret agenda to fool the public. Obviously, I believe there’s no conspiracy, that climate change is not a hoax and that the advice we give the policymakers is honest and good science,” Washington said.

Later in his talk, he said, “We’re faced by a lot of people whose business interests are affected by climate change mitigation.”

Washington’s simulations showed that cutting back on carbon emissions and concentrations in the atmosphere would help curb future temperature rises. But he called some proposed geoengineering measures unlikely to do much. These include space mirrors to reflect light away from Earth and stratocumulus cloud seeding to brighten them so that more solar radiation is reflected out to space.

He said more realistic possibilities include sequestration of carbon — sending it underground or to the ocean bottom. For the short-term, he mentioned the positive effect of reducing the amount of airborne methane and other non-greenhouse gases such as Freon.

“Climate system models are far from being perfect,” he said, “but are the best indicator of our science knowledge of how the climate system works.”

The release notes that Sandia scientist Mark Taylor came in for special praise from the speaker for a significant climate simulation on the Argonne National Laboratory supercomputer Blue Gene/P that produced a geographic resolution of twelve kilometers. “Sandia has played a major part in getting the climate community a brand new tool to study climate change,” said Washington.

Later, he said, “Scientists like Mark Taylor and others have turned to techniques like using a cubed sphere grid to make calculations parallel and therefore solvable on modern systems.” Old-fashioned maps showing latitude and longitude converged at the poles, making them hard to work with.

The talks are sponsored by Sandia’s Climate Security Program.