It's been a bit cold

My garden in the winter of 2009/2010

Last winter was unusually cold and snowy in Glasgow, UK. Already this winter seems to be even colder.

In the last two weeks we had two significant snow falls and temperatures plummeted to -15oC, staying below -10oC for almost two days.

Many countries are used to this kind of weather, but this is quite exceptional in Glasgow and so no-one - authorities nor residents - knows quite how to handle it.

Have a look at this graph of temperatures from Glasgow airport:


(View the spreadsheet of data originally from wunderground.com.)

To see just how exceptional these temperatures are, consider the mean min and max temperatures for Glasgow in December: 2.2oC and 7.0oC respectively. Compare these with Oxford's min and max December temperatures of 2.1oC and 7.4oC.

Glasgow is about 4 degrees north of Oxford in latitude and so it should show lower winter temperatures. In reality it doesn't because Glasgow benefits more from being on the receiving end of heat brought across the Atlantic by the Gulf Stream.

Apart from the obvious problems of clearing snow and ice, such low temperatures present completely new issues. At about -15oC diesel significantly thickens as the paraffin and other constituents of the fuel solidify. This blocks the fuel filter and causes the engine to lose power or fail to start, as happened in some parts of the country.

Salt also becomes less effective at preventing ice formation at lower temperatures and I saw that several major roads within the city that were certainly treated with grit (rock salt) were not free from ice. In fact, at about -21oC, no amount of salt can prevent water ice from forming.

The other issue that was seen during last year's winter and that is still evident a year on is the damage caused when water repeatedly freezes and thaws in cracks and cavities in the road. This happens because water expands when it freezes, which breaks concrete, rock, cement, asphalt and tarmac. The results are huge potholes and sunken manholes on almost every road.

I do tire of hearing people complain that our political leaders should have been better prepared under such extreme conditions. The resignation of Scotland's transport minister seemed to be more about poor media handling on his part, skillful (but ultimately pointless) attacks from the opposition and some bad luck in exactly when the snow fell (peak of rush hour on a Monday rush hour). Perhaps he did make some mistakes, but I can't tell what they were after reviewing the media coverage. On the upside, I'm no fan of this SNP government so if this speeds their exit, I will not complain.

But, all this raises the question: after two winters of unusually severe weather, should we (that is the government and individuals) now prepare for such eventiualities every winter? I'm starting to think so and I think I'll see if I can find some explanation for why our mild Scottish winter climate might be changing.