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Inuit All Along

Inuit climate petition against U.S. is rejected Is climate change a human-rights issue? The Inter-American Commission on Human Rights decided to dodge the question. Arctic Inuit submitted a petition to the commission a year ago, accusing the U.S. government of violating Native peoples’ rights to their traditional ways of life by declining to regulate greenhouse-gas […]

The Great White Hopeless

Chinese white dolphin is likely extinct The baiji, a white dolphin found only in China’s Yangtze River, appears to have gone extinct. Lipotes vexillifer has been swimming China’s longest river for some 20 million years, but in the end it was no match for China’s surging economy. In the last few decades, the Yangtze’s shallows […]

Don’t Have a Cow

About 20 percent of farm-animal breeds* are endangered, says FAO Word association time: What comes to mind when you think “endangered animals”? Odd-looking tropical frogs and obscure birds with funny names? Time to adjust your thinking: The U.N. Food and Agriculture Organization estimates that one in five breeds of farm animal are in danger of […]

He shoulda been MotY

Congrats, you guys, for being named Person of the Year.

Personally, I think it's ridiculous Time didn't give that particular encomium to Al Gore. Has any individual ever before so fundamentally changed public debate on so technical a subject in such a short period of time? Not to mention the personal drama of his redemption, etc. Guess the folks at Time didn't want to get political ... oh, wait.

On a related note, Mr. Gore would like you to send a postcard.

‘Vineland was full of grapes’–Or was it an early advertising campaign?

(Part of the How to Talk to a Global Warming Skeptic guide)

Objection: Newfoundland was so warm in the Medieval Warm Period that when the Vikings landed they called it Vineland and brought boatloads of grapes back to Europe.

Answer: Once again: you can't draw conclusions about global climate from an anecdote about a single region, or even a few regions. You need detailed analysis of proxy climate indicators from around the world. These proxy reconstructions have shown that the Medieval Warm Period (around the time the Vikings are said to have discovered North America) was not as pronounced or as warm as today's warmth. From NOAA's paleoclimate website comes these quotes:

A look back

Here are the first five of my "Top 10 climate stories of 2006," in no particular order.

National Academy hockey stick report: I'm not sure if this helped or hurt the cause, but it did confirm what many scientists already thought: it's hard to figure out the temperature of the earth 1,000 years ago. The IPCC's 2001 report said there was a 3 in 4 chance that the 1990s were the warmest decade, and 1998 the warmest year, of the last 1,000. According to the academy report, subsequent research suggests it's really a 50-50 proposition. In the end, we just don't know whether it was hotter 1,000 years ago or not. None of that, of course, affects our conclusion that humans are warming the climate.

‘The hockey stick is broken’–Well, no … but who’s playing hockey anyway?

(Part of the How to Talk to a Global Warming Skeptic guide)

Objection: The Hockey Stick graph -- the foundation of global warming theory -- has been shown to be scientifically invalid, perhaps even a fraud.

Answer: The first order of business here is to correct the mischaracterization of this single paleoclimate study as the "foundation" of global warming theory.

What's going on today is understood via study of today's data and today's best scientific theories. Reconstructions of past temperatures are about, well, the past. Study of the past can be informative for scientists, but it is not explanatory of the present nor is it predictive of the future. The scientific foundation of global warming theory contains much more than a few tree-rings and the temperature during the Medieval Warm Period.

RealClimate has an interesting article about what it would mean for today's climate theories if the MWP had indeed been warmer than today.

Now, about that pesky bit of sporting equipment ...

Yes, the last ice age started thawing over 20,000 years ago, but that stopped a long time ago

(Part of the How to Talk to a Global Warming Skeptic guide)

Objection: Global warming has been going on for the last 20,000 years.

Answer: It is true that 20,000 years ago the temperature was some 8 to 10° C colder than it is today. But to draw a line from that point to today and say, "look, 20K years of global warming!" is dubious and arbitrary at best.

If you have look at this graph of temperature, starting at a point when we were finishing the climb out of deep glaciation, you can clearly see that rapid warming ceased around 10,000 years ago (rapid relative to natural fluctuations, but not compared to the warming today, which is an order of magnitude faster). After a final little lift 8,000 years ago, temperature trended downward for the entire period of the Holocene. So the post-industrial revolution warming is the reversal of a many-thousand-year trend.

‘Greenland used to be green’–Don’t judge a book by its cover, much less a land by its name

(Part of the How to Talk to a Global Warming Skeptic guide)

Objection: When the Vikings settled it, Greenland was a lovely, hospitable island, not the frozen wasteland it is today. It was not until the Little Ice Age that it got so cold they abandoned it.

Answer: First, Greenland is part of a single region. It can not be necessarily taken to represent a global climate shift. See the post on the Medieval Warm Period for a global perspective on this time period. Briefly, the available proxy evidence indicates that global warmth during this period was not particularly pronounced, though some regions may have experienced greater warming than others.

Second, a quick reality check shows that Greenland's ice cap is hundreds of thousands of years old and covers over 80% of the island. The vast majority of land not under the ice sheet is rock and permafrost in the far north. How different could it have been just 1,000 years ago?

Below is a brief account of the Viking settlement, based on Jared Diamond's "Collapse".

What we’ve learned from the biofuels series

Future or folly? Photo: iStockphoto After spending much of the last several months thinking about the biofuels boom and its implications in preparation for this special series, we’ve come to a few conclusions. Like other energy sources, biofuels have significant environmental liabilities. Boosters’ rhetoric about “renewable energy” aside, topsoil — from which biofuel feedstocks spring […]