El Niño Heats Up

El Niño is growing stronger:



This image, from the NASA/JPL Ocean Surface Topography Team, is based on measurements taken from a US/French satellite over ten days around November 1.

Says NASA:

El Niño is experiencing a late-fall resurgence. Recent sea-level height data from the NASA/French Space Agency Ocean Surface Topography Mission/Jason-2 oceanography satellite show that a large-scale, sustained weakening of trade winds in the western and central equatorial Pacific during October has triggered a strong, eastward-moving wave of warm water, known as a Kelvin wave. In the central and eastern equatorial Pacific, this warm wave appears as the large area of higher-than-normal sea surface heights (warmer-than-normal sea surface temperatures) between 170 degrees east and 100 degrees west longitude. A series of similar, weaker events that began in June 2009 initially triggered and has sustained the present El Niño condition.

This image... shows a red and white area in the central and eastern equatorial Pacific that is about 10 to 18 centimeters (4 to 7 inches) above normal. These regions contrast with the western equatorial Pacific, where lower-than-normal sea levels (blue and purple areas) are between 8 to 15 centimeters (3 and 6 inches) below normal. Along the equator, the red and white colors depict areas where sea surface temperatures are more than one to two degrees Celsius above normal (two to four degrees Fahrenheit).

"In the American west, where we are struggling under serious drought conditions, this late-fall charge by El Niño is a pleasant surprise, upping the odds for much-needed rain and an above-normal winter snowpack," said JPL oceanographer Bill Patzert.

Swell. More here, including a map animation.

A Season of Storms

A beautiful animation of the entire 2008 Atlantic hurricane season:



It was produced by NOAA's National Hurricane Center and can be downloaded here.

Here's a map of all the tropical storms and hurricanes from that busy year. This year, by constrast, has been rather quiet.

Things Change

Yankee Magazine crowd-sources autumn:



Reports are made by people (qualification: have color vision!) around the northeastern US, who write in and say stuff like

Hi folks, Things around here are really starting to look diferent around here [sic]. We had those last few nights that got alittle [sic] cooler and it seemed like the swamp maples took the hint. Like popcorn when it starts to pop [sic]. The colors realy [sic] started to show, see ya for now [sic]

which you can read by clicking on the map. You can also register to do it yourself. It all strikes me as somehow breathtakingly wholesome.

I also like the existential connotations of the map legend.

Via Andrew Sullivan

Snow

NASA's Earth Observatory has a map animation of global snow cover from 1999-2009.



It's surprising how much of the world's land area spends a big chunk of the year under a layer of frozen water. Guess we really are still in an ice age.

Temperature Anomalies and Global Warming

Weather Underground updates this map every month.



It shows the temperature anomalies around the globe for January 2009 relative to the average between 1961 and 1990. As has usually been the case over the last ten or fifteen years, the global average temperature was above average for the month; it was the 7th warmest January on record, in fact. (And look at Siberia: it's been looking like that a lot lately - the climate seems to be changing there really dramatically.) However, among the few areas of the world that were below average were Western Europe and the Northeastern and Midwestern United States. For the US as a whole, it was only the 59th warmest January out of the last 114. (Note, too, the coolish temperatures over the central Pacific: a symptom of La Nina.)

One inevitable consequence of cold snaps during the winter is that global warming skeptics will say sarcastic things about the weather. And some people become more receptive to denialist claims - claims by people like George Will who recently wrote a denialist editorial that was pretty much entirely composed of falsehoods. But of course the fact that the temperature of the planet is gradually rising doesn't mean there will never again be any temperatures anywhere that are below average - and you can see clearly enough that a significant cold snap in some of the densely populated parts of the industrialized world is perfectly consistent with the world having temperatures somewhere in the neighborhood of the 5% warmest ever.

Ricky Rood makes a related point at his blog on Weather Underground, where he shows these maps of the continental US temperature anomalies from the Januaries of 2008 (top) and 2009. It so happened that in 2008, most of the big cities in the US were warmer than average, and this year they were colder (the major exception being the cities on the west coast). Overall, though, the months were similar for the country as a whole, and near average. But for two reasons, the denialists have had more fodder this year: 1) the colder weather disproportionately hit the places where lots of people live - if the map were a cartogram (which would make no sense) it would be overwhelmingly blue, including in big media centers where opinions tend to get amplified; and 2) the colder weather this year hit places that are naturally colder, which makes it seem more dramatic. Record lows in Oregon are gonna be chilly for the folks there, but not freezing; it's a lot more startling when it hits -40 degrees in Maine. As Rood says, "I don’t remember a lot of rhetoric that 'global warming is spurious' coming out in 2008, from say, Seattle."

Well, these points probably seem obvious to most people. And for that committed minority who don't believe in anthropogenic global warming, there is an entire industrial-media apparatus (of which George Will is obviously a card-carrying member) designed to confirm their views, and no amount of data is likely to win them over. But maps like these are still a good corrective to the impulse we all have to extrapolate global trends from the anecdotal events we read about in the news.