Time to tweak the deniers again. Here are a few articles about climate change science.
First, it’s been widely reported that the Sun seems to be going into quiet mode, and the right-wing blogosphere is full of posts about the coming of a mini ice age. Well, that’s just not going to happen and this detailed article in RealClimate explains why.
It remains to be seen whether this prognosis turns out to be true (there have been some doubts expressed), but since grand minima of solar activity did occur in the past, it is certainly interesting to explore what effects such a minimum might have on 21st century climate if it did occur. This is precisely the question Stefan Rahmstorf and I investigated in a study published last year (see also our press release. (Earlier estimates for the size of this effect can be found here andhere.) In our study we find that a new Maunder Minimum would lead to a cooling of 0.3°C in the year 2100 at most – relative to an expected anthropogenic warming of around 4°C. (The amount of warming in the 21st century depends on assumptions about future emissions, of course).
Another widely-held denier belief is that volcanoes are the primary contributor of carbon dioxide to the atmosphere. That’s not the case.
In compiling all the studies that have looked at global annual volcanic CO2 emissions, Gerlach offers a range of 0.13-0.44 billion metric tons (gigatons) per year. To further refine the range, Gerlach chooses an annual average of 0.15-0.26 gigatons. This includes all subaeral and submarine eruptions worldwide. That sounds like a lot, doesn’t it? We’re talking hundreds of millions of tons of carbon dioxide released each year. Where do humans stand in comparison? Oh, merely 35 gigatons. Yes, 35. That makes volcanoes look like small fry.
Let’s look at one more. Arctic sea ice is coming back after a period of decline. Well, not quite.
It’s been known for some time that the ice sheet in the arctic is thinning. And now, a new study(PDF) by the Arctic Monitoring and Assessment Program lays this out in grim detail.
The report lists 15 key findings about the changes at the Earth’s northern regions.Fifteen. Here are four that alarmed me particularly:
1) The past six years (2005–2010) have been the warmest period ever recorded in the Arctic. Higher surface air temperatures are driving changes in the cryosphere.
3) The extent and duration of snow cover and sea ice have decreased across the Arctic. Temperatures in the permafrost have risen by up to 2 °C. The southern limit of permafrost has moved northward in Russia and Canada.
7) The Arctic Ocean is projected to become nearly ice-free in summer within this century, likely within the next thirty to forty years.
That should do for now. I’m sure I could come up with a few more worthwhile articles if I had the time.