Fast on the heels of the hottest June to September on record*, NASA’s Goddard Institute for Space Studies reports that last month was tied for the second hottest September on record (after 2005).

Unlike NOAA, which announced its October global analysis with a major “State of the Climate” monthly update, NASA just quietly updates its data set (here).  So you have to do a little math to see that for the June through October period, 2009 now tops both 1998 (easily) and 2005 (just barely, hence the asterisk).

For NOAA, it was the sixth warmest October on record, and the fifth-warmest January-through-October period:

NCDC 10-09

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Yes, the one place in the world where it warmed the least is, of course, the good old (continental) U.S. of A. — though it was the wettest October on record for the lower-48 (see WWF’s U.S. Sees Wettest October on Record; Arkansas Records are Washed Away).

That’s the continental United States, of course.  Once again, the geographical distribution of the warming continues to be bad news for those worried about the permafrost permamelt, since temps even in the summer ran upwards of 5°C (9°F) warmer than the 1961-1990 norm over much of Siberia and parts of Alaska and Canada.  Siberia contains probably the world’s largest amount of carbon locked away in the permafrost (see here).

As for the NASA data showing its been the hottest June to October on record, I’m not cherry-picking these last four months, but rather ENSO-picking them.  The reason 1998 was so anomalously warm even beyond the human-caused trend was the uber-El Niño.  Back in January, NASA had predicted:  “Given our expectation of the next El Niño beginning in 2009 or 2010, it still seems likely that a new global temperature record will be set within the next 1-2 years, despite the moderate negative effect of the reduced solar irradiance.”

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Then, back in early June NOAA put out “El Niño Watch,” which I noted meant that “record temperatures are coming and this will be the hottest decade on record.”  So here we are.

What makes these record temps especially impressive is that we’re at “the deepest solar minimum in nearly a century,” according to NASA.  It’s just hard to stop the march of anthropogenic global warming, well, other than by reducing GHG emissions, that is.

Finally, NOAA again reports on the temperature trend from the lower troposphere (”the lowest 8 km (5 miles) of the atmosphere”) — the satellite data that began in 1979 analyzed by the University of Alabama in Huntsville (UAH) and Remote Sensing Systems (RSS).  NOAA reports that the lower troposphere warming trend for October is

  • +0.14°C/decade (UAH)
  • +0.16°C/decade (UAH

So yes, the satellite data also shows that the lower atmosphere is warming, contrary to what you may have heard.  As the AP reported last month:

“The last 10 years are the warmest 10-year period of the modern record,” said NOAA climate monitoring chief Deke Arndt. “Even if you analyze the trend during that 10 years, the trend is actually positive, which means warming.”

“To talk about global cooling at the end of the hottest decade the planet has experienced in many thousands of years is ridiculous,” said Ken Caldeira, a climate scientist at the Carnegie Institution at Stanford.

h/t Nick Sundt

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