Wednesday, 27 February 2008

Quakey-Wakey!


The biggest earthquake to hit the UK for 25 years struck last night at 0:56 and I was awake to witness it here in Withington, Manchester!

I felt the entire building shaking and saw items moving for several seconds. I kinda had a hunch on what it was after witnessing the Manchester Earthquake swarm of 2002. A couple of my neighbours popped out of their flats and I told them, yeah I'd seen it all before: this was a 3-point-something earthquake and we can all go to sleep.

But I went back and started looking for reports of it on the news. The BBC was ticker-taping about a tremor in the West Midlands, but I quickly found a Wikipedia article about it being written as I was refreshing the page. It first said it was a Manchester earthquake with unknown magnitude, but as the list of reports came in it quickly settled on being a 4.7 to 5.0 earthquake in England. Turns out it was a 5.3 in Lincolnshire. It's even reported on CNN (they found an American chap living in a timber-frame Tudor house to interview, of course!)

Sunday, 24 February 2008

Arctic Valentine

The Arctic has given us a Warm-hearted Valentine's gift!

This is going to be a short post - I keep watching Cryosphere today in order to monitor current sea ice extent. Summer's sea-ice extent loss was so dramatic I posted a couple of items, the second one being one where I predicted the amount of sea-ice for the coming winter.

Actually it looks like the majority of the winter has been better than I expected. That is, the winter was almost a record low for maximum extent wheras I expected it to be lower. In fact, for about a week, during a cold spell at the beginning of February the ice-extent was greater than a year ago by about 50k to 100k Km2.


The surprise comes in the middle of February. The Extent appears to have dropped by a stunning 700,000 Km2 in one day! When I saw it yesterday I thought it was a data error, but the extent has followed on from there instead of returning to it's previous point. So anyway, I've included an enlarged picture. It's one taken from the site, but I've enlarged it 2x and chopped out the rest of the graph. It may be that it's an error, but to give you an indication of how massive this is, it's about 5x greater than the worst single-day drop around this time last year and about 25% greater than the worst single-day drop in the record-breaking summer 2007. It means that the ice-extent (in mid-Feb) is currently at the same position as it was last April! It could go above 13M Km2, again, but given the current weather conditions near the end of February (it's quite a bit warmer than I'd expect); I'd be surprised!