The incredible dryness of cold

Frosted gingerbread roof

I’m not about to express surprise at the fact that it’s cold in winter. By the standards of a LOT of people I can think of, the temperatures we’re facing this week – an average of about -7°C during the day – are temperate, mild, even balmy by comparison with quite extensive other parts of the world.

But what never ceases to amaze me in Southern Germany is just how dry cold can be. Having spent my formative years in the insular climate of lowland areas of the UK, especially on the coast, I’m used to cold being accompanied by wet. I expect a daytime thaw even when there’s snow on the ground, and so the fact of the snow just staying the same for days on end, simply because it remains frozen and can’t go anywhere or change its consistency, is quite weird. It strikes me as eerily Groundhog-Day-like, so maybe it’s appropriate that I’m writing this post today of all days!

What’s struck me particularly today is that even though there is absolutely no snow or visible patches of ice on the streets here in the middle of the city (the picture above is of the North-facing roof of the house), the street surfaces nevertheless have an odd look to them, a pale, dusty, almost mildewed-looking grey. It’s like a thin salt crust or sprinkling of talcum, very dull and matte, and not in the least slippery. I’m guessing the tiny moisture droplets in the air are simply freezing on contact with the frozen ground and causing this strange effect. It’s definitely not salt as it darkens and then disappears if you warm it.

It’s odd how little details of a place’s climate can astonish you even after many years of living there, but at the same time it’s pleasing to be able to marvel at something that must strike many other people as ordinary or insignificant.

Postscript: Following on from a discussion of this with Rolf on Twitter, I have now been reminded that this phenomenon is called deposition or desublimation – in this case the direct transformation of water vapour (i.e. gas, not droplets) into ice in sub-freezing conditions. Thanks Rolf!

Gerbera

Oh dear, I seem to have missed almost a whole week of posting here. I’m not going to gnash my teeth and feel too guilty, though – it’s been a horrendously busy week and I’m just pleased to have reached the end of it still standing.

The semester began and brought a larger than usual flood of last-minute e-mails, phone calls and door knocks from desperate students wanting into this, that or the other class (and not even just my classes, either), and on top of that, I picked up a cold that has not impacted on my work particularly but has left me feeling rather drained.

In somewhat lesser concerns, I was feeling a little sad that the tulip season seemed to be drawing to an end – I’ve managed to have fresh tulips in the flat constantly since the beginning of their availability in the shops in early spring and seem to have gone through the entire palette of colours. However, today there were gerberas, a type of flower whose shape seems to take us so much closer to summer. I now have a yellow bunch on the living room window sill (as pictured) and a vase of gorgeous burnt orange ones in my orange and green hideyhole-cum-work-area upstairs (I must take some pictures of those tomorrow when daylight is back).