Paul Homewood has a must-read article describing a Met Office briefing paper he obtained under FOI. You should definitely read the whole thing, but here's a taster.
There have been many attempts recently to blame just about every bit of bad weather on declining Arctic sea ice. Julia Slingo, herself, told a Parliamentary Committee last year:-
“There is increasing evidence in the last few months that depletion of ice, in particular in the Bering and Kara seas, can plausibly impact on our winter weather and lead to colder winters over northern Europe".
(This, of course, came a few months after previous predictions of warmer, wetter winters, and a few months before Slingo decided Arctic ice was responsible for heavier rainfall).
The private briefing document totally demolishes her argument and that of others:-
It has been suggested that the decline of Arctic Sea Ice may drive low pressure over the UK, although this remains very uncertain at present.
And
In the long term, most climate models project drier UK summers – but it is possible there could be other influences of a changing climate which could override that signal on shorter timescales.
If low levels of Arctic sea ice were found to be affecting the track of the jet stream, for example, this could be seen as linked to the warming of our climate – but this is currently an unknown.
The Met Office Hadley Centre, working with climate research centres around the world, is making strides in determining how the odds of extreme weather happening have been influenced by climate change. However, it is very difficult to do this type of analysis with such highly variable rainfall events, so it may take many years before we could confirm how the odds of this summer’s wet weather happening have been altered by greenhouse gases.
So why did Slingo give the testimony she did to Parliament?