Snow report / Welcome to 2017

[bungo]

Another year, another data point.

Year First snow

2016 Not till 2 Jan 2017
2015 22 November
2014 11 December
2013 Don't know, out of town
2012 1 December
2011 Not till 24 Jan 2012
2010 24 November

This snow report continues from http://bungo.livejournal.com/135261.html

Comments

[bungo]

I don't feel like it's been an especially warm winter so far, but my impression of the first few winters here, a decade ago, is that they were colder.

The data is inspired, somewhat, by that collected at the large, shallow Müggelsee lake on the eastern side of Berlin.

http://www.igb-berlin.de/en/monitoring/mueggelsee

For a time I watched this closely in winter, as the lake often freezes over, but the vagary of details affects whether the ice thickness will be enough to support a skater's weight or not. There used to be nice graphs showing that thickness over several winters, and how quickly a few warm days make it go to zero. I'm disappointed to see they're gone.

(*Sigh* Open data in the natural sciences is a problem.)

All I can say about this data is that there might be two clusters: a mid-November group, prevalent until 2010, and now a "late" cluster. With so few points in each cluster, I won't say anything about significance yet. I expect this "first snow day" variable to have high variability - you need cold temperatures, moist air masses etc. all to be in the right place on the day. Move the jet streams by a few tens of kilometres on an impropitious day, and instead of snow, you'll get rain, or nothing. So this is more anecdotal data than stuff you'd drive your climate model with.

[dalmeny]

Are historical records from the Müggelsee available for comparison? (Er, don't go to any effort, I just couldn't immediately see it at the link.)

I'm pretty sure I know someone who works at the IGB.

[bungo]

Yes, they were available, IIRC. The ice thickness graphs in particular were certainly there for many (>5) years - so that it was hard to read the different years' time series: they were running out of distinct colours overlaid on a black background.

That they are down now suggests to me that IGB, or their Leibnitz parent, is getting savvier (okay, maybe more paraniod) about intellectual property. Reading between the lines on that web page, I'd imagine the price of access would be co-authorship, or at least an acknowledgement in any publication. E-mail to the two people shown would be where I would start, after a search for publications.

Since they seem to be building a network of similar lake monitoring stations, there may well be an Australian lake, and/or an Australian partner agency - CSIRO?

For general climate data, I'd start with the Deutscher Wetterdienst, [www.dwd.de] - I have no idea how open they are though. For snazzy high-profile climate change indicators, you might try the Potsdam Institut für Klimaänderungen [www.pik-potsdam.de]