Joe Bastardi is a weather forecaster who is “skeptical” of the claim that the burning of fossil fuels is leading to dangerous global warming.
Is it skepticism or is it denialism?
Neven over at Arctic Sea Ice Blog posts the following tweet from Bastardi:
August 26th is about when 2012 passed 2007 as the year with the least amount of ice ever recorded. The pictures sure make it seem like the ice has recovered quite a bit since then, don’t they?
But anyone who’s been paying attention to arctic sea ice would find this implausible, since sea ice area and sea ice extent are still decreasing even now in mid-September. If we go to DMI’s Centre for Ocean and Ice website (where Bastardi got his image), we find the following image” of yesterday’s sea ice concentration:
No sign of the “Ice increase” mentioned in Bastardi’s tweet. Why is that?
Well, a big part of the explanation seems to be that Bastardi’s tweeted pictures are not pictures of ice at all. They are instead depictions of the surface temperature of the arctic sea. Ocean water freezes at zero degrees Celsius (that’s why Celcius set the zero of his scale there — since salt water is widely available), but this doesn’t mean that the temperature readings depicted give an accurate account of where ice is and where it isn’t.
If you want to know where the ice is, you need to look at satellite images and see where there’s ice and where there’s water. Which is exactly what the scientists do to generate the extent and concentration maps like the one above. (Neven has a nice animation of the difference between August 26th and September 13th here.)
A few further tidbits on Bastardi to help us evaluate whether he should be counted as a denialist:
Here Bastardi argues that the fact that submarines have been able to surface at the North Pole in previous decades shows that current sea ice decline is nothing unusual. What’s missing from his article is a discussion of the relationship between holes in the ice and the amount of overall ice that is present in the arctic. Notice, for example, in the below concentration map, that there is very little dark purple.
Those dark purple patches are the only regions that have 90% to 100% ice coverage. There is currently a whole lot of room for submarines to surface.
Also notice this comment by Bastardi where he claims, “By all counts, so-called “greenhouse gases” cool the earth and the atmosphere.” This betrays a profound misunderstanding of basic physics.