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Comment The press will correctly say it was "government" (Score 1) 435

no US agency has said anything of the kind

Wrongo bongo. Here's the Joint DHS and ODNI Election Security Statement. It begins: The U.S. Intelligence Community (USIC) is confident that the Russian Government directed the recent compromises of e-mails from US persons and institutions, including from US political organizations.

Comment Historical context (Score 5, Informative) 99

The Great Barrier Reef has been monitored by AIMS since 1980. The first mass bleaching event occurred in (then) record warm year 1998 when 50 per cent of the reefs suffered bleaching. The next in 2002 where 60 per cent of reefs were affected. In both events, about five per cent of the Great Barrier Reef's coral reefs were severely damaged. (compared to 22% now)

The impact from this most recent bleaching event, the most widespread and severe ever recorded on the Great Barrier Reef, is still unfolding.

Comment Re:we were just heading back into an ice age. (Score 1) 221

No. Since the last interglacial 120000 years ago (the Eemian, warmer than the current) and the one we're living in (the Holocene) there has only been a glacial period (cold ... ).

My mistake. Thanks for correcting.

"Current global temperatures of the past decade have not yet exceeded peak interglacial values but are warmer than during ~75% of the Holocene temperature history."

XKCD would have done well to include the error bars. They do illustrate this additional variability towards the right side between 16,000 and 15,500. If you include the error bars you can see that there is no contradiction. Even still, Marcotte was published in 2013. We're about 0.3C hotter now than the hottest observed temperature at that time: . That may very well exceed even the error bars and cover that last 25%.

Comment We're committed - but not to the extent she says (Score 2) 221

I took away from her study that, as far as she could extrapolate from the available data on climate/temperature cycles going back 2 million years, that we were pretty much smack at the point of the two curves one would expect during this point in time

Not quite. We reached the peak of the current interglacial about 8000 years ago. That peak is the result of Milankovitch cycles and the carbon, albedo, and other feedbacks - just as the peaks that came before. Temperatures have been falling slowly since then until the last 150 years when we increased atmospheric CO2 by about 70% by burning fossil fuels. Temperatures have risen along with the recent CO2 increase, just as you'd expect. The question she's trying to answer is, if we stopped releasing CO2 today, how much more warming would we observe just due to the CO2 we've already released. She uses the CO2 and temperature correlation over the previous glacial/interglacial periods to estimate the impact of CO2 on temperatures.

Gavin Schmidt shows why this is flawed and, given our current circumstances, likely to overestimate the impact. Here is a snippet: "In the previous post, I outlined how the combination of carbon cycle feedbacks to the Milankovitch forcing and the climate system response to CO2 gives rise to this correlation and that – by itself – it can’t be used to define the latter term. Furthermore, because the regression is being defined over ice age cycles where the biggest changes are related to the (now disappeared) North American and Fenno-Scandanavian ice sheets, the regression might well be much less for situations where only Greenland and West Antarctica are 'in play'."

Comment Re:we were just heading back into an ice age. (Score 5, Informative) 221

There have been several glacial/interglacial periods over the last 120,000 years. The peak of the current interglacial occurred about 8000 years ago. Since then temperatures have been slowly falling... up until about 150 years ago when something happened and temperatures dramatically reversed course.. Here's just the last 20,000 years by XKCD:

Comment Re:She's right (Score 4, Informative) 221

I think the XKCD comic is rather more clever as he uses peer reviewed science. Your other perspective presumes that temperatures in Greenland represent temperatures around the world. That's not going to work. It looks like he snipped only certain parts though as using the whole core wouldn't fool "even the dimmest denier at WUWT" as Sue explains here:

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