On Monday, 21 September 2015 19:32:37 UTC+1, Graham Easterling wrote:
SNIP
Graham

The data originates from the Met Office but it looks like it's only updated monthly which is probably the right interval to look for changes, of course anomalies are only as good as the accuracy of both the SST and the long-term average they use to produce it. I can only imagine the extraordinary detail comes from satellite observations.

Bruce.

That's a good point about long term averages, I have some concerns over their accuracy.

Also it would be good to know exactly how the anomaly maps are arrived at.. Is the one you use purely satellite, or does it also include surface measurements? Maybe the other Graham (P Davis) can shed some light on this. Whenever I see tightly packed SST isotherms, as off Brittany, I'm a bit wary. It reminds me of the tightly packed isobars you get on say XCWeather when they get an incorrect pressure reading, or the MetO rainfall actual/anomaly maps for west Cornwall when Scilly double recorded rainfall for a few months.

Maybe I'm just naturally suspicious!

Graham

I use XCWeather a lot and it has many good points. But the algorithm used for drawing isobars has no "brain" whatever. You can get geostrophic wind speeds that are several times the speed of sound.

Tudor Hughes, Warlingham, Surrey.