david

The countries of the G8 today approved a target of 2° C rise in global average temperature above the natural, preanthropogenic climate, that they resolve should be avoided. The Europeans have been pushing for 2 degrees as a target maximum temperature for several years, but this is something of a development for the Americans. We posted recently on two new papers about what it would take to limit global average warming, finding that it would require fairly strong change in trajectory. About 2° C as a target, we wrote,

… even a “moderate” warming of 2°C stands a strong chance of provoking drought and storm responses that could challenge civilized society, leading potentially to the conflict and suffering that go with failed states and mass migrations. Global warming of 2°C would leave the Earth warmer than it has been in millions of years, a disruption of climate conditions that have been stable for longer than the history of human agriculture. Given the drought that already afflicts Australia, the crumbling of the sea ice in the Arctic, and the increasing storm damage after only 0.8°C of warming so far, a target of 2°C seems almost cavalier.

Nevertheless, we view today’s development as a constructive step.

Susan Solomon, ozone hole luminary and chair of the Nobel Prize winning IPCC, and her colleagues, have just published a paper entitled “Irreversible climate change because of carbon dioxide emissions” in the Proceedings of the National Academy of Sciences. We at realclimate have been getting a lot of calls from journalists about this paper, and some of them seem to have gone all doomsday on us. Dennis Avery and Fred Singer used the word Unstoppable as a battle flag a few years ago, over the argument that the observed warming is natural and therefore there is nothing that humanity can do to alter its course. So in terms of its intended rhetorical association, Unstoppable = Burn Baby Burn. But let’s not confuse Irreversible with Unstoppable. One means no turning back, while the other means no slowing down. They are very different words. Despair not!

[Read more…] about Irreversible Does Not Mean Unstoppable

The physical impacts of the global warming forecast can be bracketed with some degree of statistical confidence. Biological effects are more difficult to gauge, except in special cases such as the likely demise of polar bears that would result from the demise of Arctic sea ice. The societal effects, however, are nearly uncharted territory, at least to me. Perhaps the topic of global warming suffers from the same sort of cultural divide as university faculties, between the techies and the touchies; that is the sciences and the humanities. A new report (pdf) called The Age of Consequences, just released by the Center for Strategic and International Studies and the Center for a New American Security, tries to bring the social sciences, in particular history, geography, and political science, into the forecast of climate change in the coming century. It makes for fascinating if frightening reading. [Read more…] about The Forecast in the Streets

The summer of 2007 was apocalyptic for Arctic sea ice. The coverage and thickness of sea ice in the Arctic has been declining steadily over the past few decades, but this year the ice lost an area about the size of Texas, reaching its minimum on about the 16th of September. Arctic sea ice seems to me the best and more imminent example of a tipping point in the climate system. A series of talks aimed to explain the reason for the meltdown. [Read more…] about Notes from The Gathering #5: Arctic sea ice: is it tipped yet?

Just a few minutes ago Chappellaz et al presented the deepest dregs of greenhouse gas concentration data from the EPICA ice core in Antarctica, extending the data back to 800,000 years ago. In Al Gore’s movie you saw what was at that time the longest record of atmospheric greenhouse gas concentrations, back to 650 kyr, and their astonishing correlation with Antarctic temperature. This iconic superstar record has probably consumed as many eyeball-hours as any in climate science, alongside other classics such as the Jones et al. global temperature trends, the Moana Loa recent CO₂ record, and the hockey stick. The Antarctic CO₂ record has spawned countless internet rants about the CO₂ lag behind temperature, and the circle of cause and effect between CO₂ and climate. And the new data say … [Read more…] about Hot off the projector #3: Atmospheric CO₂ to 800 kyr ago

Steve Milloy has let fly with the results of his twisted survey of climate scientists, pretty much as we expected. It’s not worth analyzing in any great depth, I’m sure we all have better ways to spend our time, but one tidbit jumped out at me. [Read more…] about Did we call it or what

Daniel Botkin, emeritus professor of ecology at UC Santa Barbara, argues in the Wall Street Journal (Oct 17, page A19) that global warming will not have much impact on life on Earth. We’ll summarize some of his points and then take our turn: [Read more…] about Global Warming Delusions at the Wall Street Journal

I got an email Climate Expert Survey today from DemandDebate.com, a creation of Steve Milloy. Milloy has practiced to deceive before in the climate arena, and his junkscience.com, claiming to debunk the junk science of others, is actually a terrific source of specious deception in its own right. This survey looks like another such initiative. (Note added later: If you get a copy of this, post a comment or send us an email. We’d like to keep track.)

[Read more…] about The “Have you stopped beating your wife yet (yes/no)” questionnaire