Weatherdem's Weblog

Bridging climate science, citizens, and policy

NASA & NOAA: Global September Temperatures Nearly Broke All-Time Record

Leave a comment

In the past week or so, NASA released data and NOAA released a report confirming climate activists’ fears: 2009 is going to challenge global temperature records.  There are a number of reasons this is especially troubling to me, which I’ll get to below.

First, the news is this.  Two independent scientific agencies confirm that September 2009 had the 2nd highest surface temperatures on record.  Dating back to 1880, the only warmer September occurred in 2005.  From NOAA: the combined global land and ocean surface temperature was 1.12 degrees F above the 20th century average of 59.0 degrees F.  NASA’s measurement, probably the best in the world, indicated a 1.17F anomaly, very much in line with NOAA’s calculation.

These readings follow an additional announcement from NOAA that global sea surface temperatures broke the record for warmest in August.  The June-July-August averaged temperatures were also the warmest ever recorded.

So let’s get the most obvious result out of the way.  Contrary to climate change denyers, global warming hasn’t slowed down, stopped or reversed.  To the contrary, it’s as strong as it has been all decade, and looking like it could start setting records again soon.  That’s pretty bad news.

The first reason this news is troubling is the continuation of the current solar minimum, the longest in nearly a century.  Despite a 2-year time-period of constant low solar irradiance, Earth’s surface temperatures continue to rise.  That’s exactly the opposite of what the denyers said was going to happen, so they’re left with manufacturing nonsensical trends and explanations.

So what’s causing the most recent temperature recordings?  Well, in addition to the increasing warming that our species is driving, other temporary strong signals are coming through.  In this case, it’s an El Niño, the second troubling news.  It’s troubling because so far, this El Niño is weaker than it was forecasted to be late this summer.  That by itself isn’t too surprising – accurately forecasting El Niño intensity is notoriously difficult.  But if the El Niño were stronger, the recorded warming would likely be even higher.  What remains to be seen over the winter is whether the El Niño strengthens like models are indicating it will.  It is expected to reach peak strength around December/January.

Now, it’s also important to realize that surface temperatures lag behind forcings like El Niño.  What that means is that while El Niño should peak in the next couple of months, the full warming signal in atmospheric temperatures probably won’t happen for 3-6 months beyond that.  So on a month-by-month basis, I fully expect global temperatures to break records within the next year as El Niño winds down.

Unfortunately, I don’t expect much relief after that.  Like I wrote above, the human forcing still hasn’t been exhausted.  We’re already seeing 1.1-1.2F warming with low solar input and a weak El Niño.  As positive feedbacks kick in and get stronger, 1F warming is going to seem pleasant.  Moreover, the 2000s are going to be the warmest decade in recorded history.  Even with a moderate La Niña and low solar irradiance, the 2008 was the 2nd coolest year of the 2000s, but 10th highest on record.  Without quick, concentrated action, the 2010s aren’t going to be any better.

Cross-posted at SquareState.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s