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Woops! BBC thought police letting one slip by again!

Yesterday on the 'Today' programme an item about the decline and resurgence of the British butterfly population came on. Why had so many species declined? Among other things, the interviewed expert asserted, was that the summers were so poor! Poor? Poor? What's that mean? Surely it cannot mean NOT HOT ENOUGH?

Re: Woops! BBC thought police letting one slip by again!

In the context of butterflies, a poor summer means a wet summer rather than not being particularly hot. As I understand it, butterflies don't fly in the rain, they shelter while it's raining. So the wetter the summer, the less butterflies fly, and the less flying they do the less they breed.

As far as the Greenies are concerned, they claim that any flooding events in the summer (like Boscastle a few years ago) are evidence of AGW but they also claim any hosepipe ban in the summer is also evidence of AGW. I would imagine that the Greenies at Radio 4 would go along with this incoherent position that summers will be both wetter and drier at the same time due to AGW.

I checked what the position of UK climate scientists is on whether UK summers are predicted to be wetter or drier using this webpage:

link

Using the climate change scenario from 1991 (CCIRG91) they weren't sure whether summers would be wetter or drier, the computer models were giving differing results for the direction of change.

For the climate change scenario of 1996 (CCIRG96) they came to the conclusion that summers in the south of the UK would be drier and in the north of the UK would be wetter. Another study in 1998 (CCIRG9 confirmed the 1996 study.

For the climate change scenario of 2002 (UKCIP02) it was found that the whole of the UK (including Scotland) would experience drier summers. There has been another study in 2009 (UKCIP09) but I haven't bothered to check the results from that one.

Drier summers for the whole UK means that UK climate scientists are predicting that butterflies should be doing very well over the whole of the UK.

Re: Woops! BBC thought police letting one slip by again!

Just for completeness, this is the result for whether summers will be wetter or drier for the most recent study UKCP09 which is summarised on a DEFRA webpage:

link

"Average summer rainfall across the UK may decrease by 11% to 27% by the 2080s

But while this is the average, there will be a big change in rainfall between the seasons, with winters becoming wetter and summers drier.

Under the medium emissions scenario, by the 2080s, rainfall in the South West may be 23% lower in the summer, and 16% higher in the North East in the winter."