Looking at it now, I think I should have used different colours for the text, and maybe not have written it by hand, still, you get the idea.
I took the mean sea level data from all available tide gaurges in 1991 and from 2008, worked out a yearly average for each location, then calculated the average yearly sea level rise. It's not the most scientific method, I ought to have pulled all the data and found the yearly rise for every year, and figured out the averages from that. But, sadly I'm not a research scientist, I'm just one of those unemployed chaps passing my time.
Some of the tide gauge data was missing, I guess back in 1991 not all locations had gauges, and sometimes they cock up, so I've culled any really bad data, to maintain integrity. This is a table which I used for the map above.
|Location||Sea level change|
between 1991 and 2008
|Mean sea level rise|
Its all over the shop, I guess there are local geological features which cause this, other than anthropogenic climate change caused sea level rises. In some places regions are sinking, or rising, some places get more of a battering from fetches and waves, or building policy has cause the land to sink, all outwith climate change.
I can't remember on which blog it was, possibly many of them, but in the comments someone was criticising IPCC data, and saying "but sea levels are only rising by 3.3mm/year", I thought I'd look into this a bit closer.
In the UK, there's only one or two places with that sort of average sea level rise. Maybe 3.3mm/year is the global average, but that's not very helpful for the people of Milford Haven or Cromer who are seeing rises about three times more rapid than that. There's just so much variation around the UK alone, that one average figure is no use to anyone but national newspaper headline writers, and positively misleading for anyone making longterm planning decisions.