Tuesday, April 19, 2016

No, the Sun Isn't in Long-term Rapid Cooling

The WUWT crowd are excited because of this graph:


The Sun is rapidly cooling! So global warming will start reversing any day now, and by 2020 we'll be back to zero anomalies and this AGW crap can be put to bed and the legal prosecutions of scientists can begin. (Or something like that, I guess.)

Sorry, but the Sun goes through dips and spikes like this several times a year, typically (though I don't know the reason.) Here is a graph of the same data as above, but starting in Jan 2014 instead of Jan 2016:

By starting the graph in Jan 2016, WUWT makes it look like the first spike of the year is something unusual. But it's just business as usual....  (I commented on this at WUWT, but -- cowards -- they deleted my comment.)

Reminder: anyway, the climate's sensitivity to changes in solar irradiance is very low, ≈ 0.1 W/m2 or less.

PS: Leif Svalgaard of Stanford says these spikes are due to large sunspots.


EliRabett said...

There was a big sunspot recently. Sunspots are much colder than the surface. QED

David in Cal said...

David, you might have mentioned that Anthony Watts pretty much said what you did.

"A look at the sun itself suggests it may simply be due to a very, very, large sunspot rotating through the Earth-View. My guess is we’ll see a rebound in TSI once it crosses the horizon. Occam’s Razor. If nothing else, this demonstrates that sunspots can have quite a large, if only temporary, forcing on TSI and Earth’s received energy budget."


David Appell said...

Watts' headline gave a very differnt impression. As always, he had to be contrary, no matter what.