There has been a lot of talk about the ‘Indian Summer’ that arrived in the UK at the end of September. I have discovered that the term refers, not to colonial Britain and the days of the Raj as I had assumed, but to the Native American Indian andwarm weather between September and November.
I was asked by another blogger what my thoughts on it were and I wasn’t that impressed because I first heard the term when I was a kid and remembered going back to school in September from my summer holidays in some glorious ‘Indian Summer’ weather. I’m also very aware of the accusations of climate cowboy 'skeptics', often justified, that every time there is warm weather it is global warming and every time it is cold it becomes just weather.
The Indian Summer weather is due to break tomorrow from temperatures in the high 20s Centigrade to the high teens which are still fairly mild if more average for the time of year. But as the week has gone on I have become more impressed. It’s not like 2010/2011 being the coldest winter in 15 years but we are recording some of the hottestdays ever and certainly in living memory. We have had a Barbecue Autumn! When it comes to temperatures these have been real outliers on any bell curve constructed for temperatures, pushing for a new warmer average.
So is it Global Warming?
Yes and No. We really need to get away from generally attributing weather events to man made climate change. This is because even if temperatures are the ‘warmest in a century’ or similar types of record, climate cowboy ‘skeptics’ will always retort that; ‘It was just as warm over a century ago, so who was driving SUVs then?’ Even if extreme events are truly record breaking, according to instrument records, it is unlikely that similar have never occurred something in the past.
The case that needs to be made is that the frequency of extreme weather events can be predicted using a bell curve. It is reasonable to say that something is a once in a century type event for example according to the records. It can now be seen that such rare events are now occurring more often than they should be. Both hot and cold records are still occurring but the situation now developing is that there are more heat related extreme records that cold, which is exactly what has been predicted by AGW theory.
So recorded warmer weather or any climate extreme is NOT global warming or climate change they are new data point pushing the average conditions toward a changed and warmer climate.
Good post.
ReplyDeleteI didn't realise it referred to North American 'Indians'.
I do tend to disagree with the idea that individual weather events can't be associated with AGW. Although I agree that to do so it must be done with care. And one must always be careful about falling for the tendency to associate anything unusual with what you're looking for. Confirmational bias is a danger to be wary of.
However I agree with Stu Ostro that we're starting to see events that can be associatd with AGW. And I think I've done that regarding the low pressure dominated summers we've been having in the UK, link.
I have thought a lot about this and there is now some published research linking global warming to specific weather events. They do conclude that the events were either caused or at least made worse by GW and this is usually given by a 'more likely'. For example;
ReplyDeletehttp://news.bbc.co.uk/weather/hi/news/newsid_9399000/9399694.stm
So it is probably fair to say that since there is an almost certainty that man's emissions have caused global warming, all weather, every day, extreme or not, must have a component that is due to our influence.
But I think if asked by anyone, skeptic or not, if any specific events are due to warming I'd say it can't really be shown but that event provides a data set that is now added to the overall trend of climate and we know which way that trend is going.