In message , Dave Cornwell
writes
Looking at the historic charts earlier I noticed that there were
several, especially early on, that didn't look that cold. I know there
were several threatened thaws (probably based on expected evolution of
those charts)that didn't happen. After a very snowy start I seem to
remember much of the UK and Europe remained snow covered. How much
would that have depressed the temperature had there not been such
widespread cover?

I think that, especially when winds are light, a deep snow cover can
depress temperatures quite a lot, though I'm reluctant to try to put a
figure on it.

I wonder if the same charts showed up now whether the same expectation
of cold would materialise. I doubt it, with Europe being relatively
mild still, sea temperatures warmer and I suppose +1C for GW.

Yes, sea temperatures must have a big effect.
--
I'm not paid to implement the recognition of irony.
(Taken, with the author's permission, from a LiveJournal post)