When you get a cold snap in the local weather, it means that somewhere else got somewhat warmer. Weather is a case of local shifts in energy balances. Climate changes on the other hand are an overall shifting due to underlying changes in energy inflows and retention. You can really only see them looking at decades of statistical shifts in weather.
However a lot of people confuse weather changes with climate changes.
Such was the case in a shift in the weather in the northern hemisphere and northern polar regions during December. Northern Europe, North America, and Russia had their arses frozen off with up to a 7C drop in normal temperatures in Russia, while Greenland and the north pole had a relatively balmy time with temperatures up to 7C higher than normal.
This weather anomaly is displayed on the north pole centered diagram on the right. The blue to purple shows abnormally low temperatures. The green to red shows abnormally high temperatures. All that happened was a shift in the usual energy levels within a normal statistical variation, albeit one closer to the extremes than usual.
The polar areas got temporarily warmer, and the continental areas around the pole got temporarily colder. The amount of energy involved remained the same.
As the Economist says in Oscilloscope.
To try to make a climatic point either way out of a patch of unusual weather, though, is normally to be on a hiding to nothing, and so it is this winter. No one with any claim on the public’s respect has ever said that all of the natural ups and downs of climate will be ironed out onto a smooth upwards trend by greenhouse gases; their effects are expected to show up not so much in particular events, but in statistics. The reverse of the same coin is that there will still be cold snaps in a warming world.
The rest of the economist article speculates on the implications for the northern sea ice for the next few years. I’m sure those will have the CCDs out talking about weather rather than actual climate change.
So it is always fun looking for the foolish who think that weather is climate. This post comes after reading a rather stupid post by Democracy Mum. I wonder how many similarly scientifically illiterate posts confusing weather with climate have and will be written. I’m sure that there will be links to such posts written since December. Help DM out and add them in comments and I’ll add them to the post to show that she is not alone.
Update: I was reading Poneke’s weblog (looking at his analysis of ‘climategate’) and found this post on the subject on Jan 8th. Like his comments on ‘climategate’, that I will get around to writing a post about, it is clear that he doesn’t understand the science of what he was looking at. He also doesn’t understand scientists. His post on ‘climategate’ makes that perfectly clear.