Saturday, May 19, 2012

Global temperature maps

You may want to bookmark this page if you are often tempted to look at the regional temperatures "right now". Click (or shift-click or CTRL-click) any graph below to zoom in.

First, NOAA's El Niño unit has introduced a new, visually attractive map of the current surface sea temperatures.

It's fun to see how the Gulf Stream makes Europe warmer. Look at the dark blue (cold) color near the East Coast Canadian beaches. Even Northern Norway which is more than 25 degrees of latitude more to the North seems warmer! The temperatures go from less than 32 °F, the freezing point, to 90 °F, a good reason to think that a change by a degree or two can't make a difference.

Now, the temperature anomaly – the difference of the temperatures above minus the average/normal temperature for this season combined with the same place – is mapped below:

We're living in ENSO-neutral conditions as the recent La Niña episode ended a month ago or so, at least the conditions ended. I think that the warm neighborhood of the Western beaches of South America indicate a coming El Niño; the red, warm anomaly is likely to spread to the West in coming months.

Finally, you may want to follow the temperature anomalies on the whole globe, including the land, here:

This map at the server predicts the average temperature anomaly in the coming 8 days and the predictions of these quantities by meteorological models at this timescale have become so good that you will actually not be able to distinguish it from the truth 8 days from now. Note that the land is always much more colorful than the oceans: it is easier to change the temperature of the land, in either direction, while the ocean tends to keep more constant temperatures.

Right now, you see some very cold conditions in the Western continental United States and central Canada, very cold conditions in much of the Antarctica. There is a hot spot in New England, in Russia near the Euro-Asian border, a smaller region in the Antarctica, and a few others. I think you wouldn't be able to say whether the global mean temperature is above the normal or below the normal by looking at a similar graph. The El Niño or La Niña waves seem pretty invisible on this map, too. I think it's always the case but I haven't watched this map for too long so far.

For polar caps, see The Cryosphere today. The global sea ice anomaly is approximately zero right now – the average conditions relatively to recent 30+ years.

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