Interitus

People are focusing too much on ice extent - it is not especially significant at this time of year as it reaches its maximum in March. Even if the arctic is essentially ice-free in summer, as has been predicted could be the case by 2030, it would largely refreeze with thin ephemeral ice each winter. What is significant is that now it is largely thin first year ice which will be unlikely to survive to next winter even if the summer is not as warm as last year. The lower albedo of the darker sea surface then reinforces the warming of the area and delays ice recovery. The signs are that we are seeing a depletion in the overall ice volume which is a function of area and thickness. As for thickness measurements there is little fresh data to hand at the moment, but this is almost an irrelevance. It seems to be the opinion here that "the ice has recovered now where's the problem?" but on the contrary, any judgement of recovery should be reserved until the ice reaches it's next minimum.

I know nobody wants to hear it but Grey-Wolf is correct - January 2008 Northern Hemisphere sea ice extent was the fifth lowest on record for the month of January, 8% below its extent in 1979 when satellite measurements began, according to the National Snow and Ice Data Center. January was the third straight month that a new monthly minimum Arctic sea ice record was not set, following a string of five months in a row where monthly records were set. However, while the ice extent is not at a record low this month, the volume of the arctic ice is probably at a record low for January. The ice is exceptionally thin across the Arctic this winter, and the edge of this thin first-year ice extends all the way to the North Pole.

Those who think that winters haven't changed and the memories of the past are viewed through rose tinted specs might like a quick look at this - http://www.derbysulzers.com/200179.html No, I am not a gricer!

Here in north Cheshire we had sleet from between about midnight and 4 am last night and was a bit of a suprise to see the widespread development of precipitation in NW England, Southern Scotland and N.Ireland on the radars - though looking at the charts on the retrocast thread the possibility maybe might have been spotted. Certainly they hinted at more development than was expected further south. All in all though, just a few flakes here passes for excitement, pathetic. The forecast for the Californian Sierras this weekend is for up to 10 FEET of snow.

However Flash is exposed whereas Wanlockhead is in a valley so is probably the colder location purely on topography.

Yes Google earth is handy good point, but I wasn't totally sure to the accuracy and resolution of it's source data and the OS maps show give fairly definitive information, cheers

Click the Streetmap links - Wanlockhead lies between 400 and 430 metres. Flash lies above 460 metres.

It is thought that winter refreezing would only be circa 50%

I have to say that reading this discussion that marginally higher ice coverage than last year is some sort of refutation of GW is clutching at straws. For example the charts posted of this year vs last can be neatly explained by the AO - notice last year's ice-free Svalbard countered by a snow covered Europe, the reverse of this year. Moreover, this ice is ephemeral - it will all melt by the end of the summer. There is now very little 'old' ice (>10 years) and of course all talk of areal coverage misses the fact that the ice has drastically reduced in thickness also. I would recommend anyone interested may care to read the last few Jeff Masters blogs on wunderground. There are serious concerns that within 30-40 years the arctic will be essentially ice-free.

Since 1979 ice coverage is about 10% less in winter and 20% in summer - it reached record lows for November and December last year. More alarmingly between 1958 and 1997 its thickness reduced by 40% - though this may have averaged more like 10-15% if it had been measured at different times - it's hard to be consistent as the ice is constantly moving. There is an interesting article about this on the wunderground site at the moment.

The warmth of December and January was far too extensive to be explained by any jet oscillations. The finger points towards late freezing of the Arctic sea ice.

Sorry o/t love that abbreviated link It's been sleet here in North Cheshire for a couple of hours, but I don't think it's purely ground temps as has been suggested because dew points are low. There is a complicated layer of advected milder air above judging by the make up of the precipation - no flakes are present, but partially thawed crystals that appear to have melted/frozen and melted again.

For those worried about the temperature rise in southern areas, you might take heart from the reports from Dunkeswell in Devon.

Depending on the easterly wind I wouldn't be surprised to see the typical bifurcation of this precipitation where the east and west parts of northwest England see significant snowfall whereas in the centre - Wigan, Warrington etc this is substantially reduced by subsidance over the Pennines. Happens as often as not - watch those radar sigs.

Hi, coconut palms struggle even if grown indoors because of lack of light and humidity. But they are not hard to get hold of - they are quite often sold in the big diy chains as houseplants. If you would like to try a palm of similar appearance the closest may be the Mule pale, xButiagrus nabonnandii - a cross between a butia and a syagrus. Forget the 'polar palms' they are just trachycarpus fortunei which are agreed to be perfectly hardy for most of the country.

No, as a keen grower of 'exotic' or sub-tropical plants I would have to say that the USDA climate zone maps based on average absolute winter minima only give at best a simplistic comparison of climates. Certainly, there is no serious similarity to any Floridian climate anywhere in these isles. They can be a starting point though, giving encouragement to grow many plants that may not be expected to survive - but often that's all they will do because while our lowest temps might not kill them, a combination of persistantly low temperatures, damp and low light levels will prevent them from thriving. As for palms, there are many which are being grown with a degree of success - for example varieties of trachycarpus, butia, washingtonia, jubaea, brahea, chamaerops and indeed phoenix like the Canary date palm to name but a few. However, the hardiest species generally agreed to be the needle palm, rapidophyllum, is considered pretty much a waste of time growing here because whilst it tolerates temperatures as low as the UK record, it does not receive enough summer heat to make any serious growth.

For weather in this area the Tromso University website has a wealth of data, including a fabulous archive of timelapse webcam video. It's a stunningly beautiful place.

Very interesting stuff Iztok. For years I have never understood why people in this country haven't gone out to deliberately try and find record-breaking minimum temperatures.

Yes, but that's in the last 12 hours. Look at the time that the Middlesbrough depth was posted. It's not impossible obviously, but I would just hope that people take their reading with the appropriate rigour, if they're to be believed. The raingauge network is far more extensive than people might imagine.

Slightly dubious I feel. The highest rainfall figure yesterday was 8.8mm at Leconfield.