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Something strange in the atmosphere

From correspondent Gras Albert:

AMSU's global temperature web page, if accurate, is showing an abrupt climate change event, Channel 5 (600mb, 14,000ft) is showing a 0.8degC drop in global average temperature in just 9 days. This is remarkable, not repeated anywhere in the satellite record, let alone in March which is typically a warming month.

Similar, though not quite so severe drops are shown in Channel 6 (400mb, 25,000ft) and 7 (250mb, 36,000ft) indicating that it is troposphere deep, perhaps a Super Tropospherical Cooling event!

Although as my correspondent continues, it could just be a problem with the satellite. Here's the image. The AMSU page is here.

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Reader Comments (29)

Try the plot with 2002, 2008, 2009, 2011 and 2013 selected at 400mb.

Mar 25, 2013 at 12:19 PM | Unregistered CommenterNiels

It only needs the upside-down treatment made famous by Michael Mann and Tiljander. Unprecedented.

Mar 25, 2013 at 12:21 PM | Registered CommenterRichard Drake

Looks broke to me.

Mar 25, 2013 at 12:26 PM | Registered Commenterrhoda

The character of the signal doesn't hint at instrument malfunction and three readings result trend lines seemingly concurring (from the same instrument?) seems to indicate an observed rather than an instrument induced effect. After some small scouring I've yet find the recipe for the wiggly lines - one has to assume that they are massaged composites of the array of sensors on Aqua and that the contribution from any single sensor has significant filtering and weighting applied.

It may well be an instrument malfunction masked by filtering in the delivered "product" - but if it isn't and it keeps plunging as it is presently on the satellite data Java app - an extraordinary event unfolding?

Interesting - but as Niels says - not wholly unique... - let's see where it goes :)

No doubt CO2 induced </sarc>

Mar 25, 2013 at 12:30 PM | Registered Commentertomo

Roy Spencer has responded

We won’t know till we compare the recent drop to the other 2 satellites. It looks suspicious to me. The noise in that channel has been rising for a couple years now, and it could be it’s close to failure.

Mar 25, 2013 at 12:33 PM | Unregistered CommenterGras Albert

2013 looks kind of similar to 2007.

Mar 25, 2013 at 12:34 PM | Unregistered CommenterJeff Norman

I repeat:

Try the plot with 2002, 2008, 2009, 2011 and 2013 selected at 400mb, there is nothing unusual about this, and nothing wrong with the measurement.

Mar 25, 2013 at 12:35 PM | Unregistered CommenterNiels

Ooh-er, it uses Java! OT: People should be aware that Java in the browser (as opposed to Javascript, which is different) is dangerous and can and does lead to your computer getting hijacked. Turn if off! See Sophos or PC Mag or search for yourself. If you must use it, use it in a virtual machine (Virtual Box, VMWare).

Mar 25, 2013 at 12:35 PM | Unregistered CommenterBitBucket


you actually have to trust somebody, sometimes... I know knowledgeable but paranoid folk who have Javascript turned off by default ..

Using a VMs as a sandpit is not a bad thing - but beyond your average user. Awareness that web browsers can be (trivially in some cases) hijacked and that it's important to keep them patched up to date is the prime message about web security to my mind at least.

Mar 25, 2013 at 12:51 PM | Registered Commentertomo

A Freezington Event.

Mar 25, 2013 at 12:52 PM | Unregistered Commenterkim

Tomo, I too disable Javascript. I use a VM to post here. The thing about trusting people is that you can't. It is not that the website owners are dishonest but that attackers are many steps ahead. Many websites serve up malware without the owner's knowledge. You only have to look at the latest research on open Telnet servers to know that sysadmins cannot be trusted to get it right.

Mar 25, 2013 at 1:09 PM | Unregistered CommenterBitBucket

"Looks broke to me."

And me. I see that little square as the satellite about to burn up on re-entry.. :-)

Mar 25, 2013 at 1:15 PM | Registered Commenterjamesp


The Aqua data starts in June 2002, no data for March??? Are you aware that the Aqua satellite has been suffering from sensor drift resulting in a warm bias which Dr Spencer suggests is now about 0.2degC at 600mb? In any case absolute temperatures are not relevant, it is the rate and magnitude of the decline that is unusual.

Channel 6 (400mb) for 2004 & 2007 have similar deltaT declines for shorter periods and of less magnitude, there has never before been a recorded decline so large so fast.

0.8degC is about 4% of 600mb temperature, what possible physical mechanism could explain troposphere heat content declining by something approaching 4% in 9 days?

Mar 25, 2013 at 1:30 PM | Unregistered CommenterGras Albert

I hear you - but there is a point of diminishing returns. There are some truly frightful vulnerabilities in common "user" software and I concur the server side things aren't much better.

If penetration is to be really successful - the user won't be aware - at all. The only way to see what's happening is constantly sniffing network traffic and even then a novel exploit might well conceal itself well enough to pass through the net :-)

In essence - the only way to protect from catastrophe is to ensure effective data redundancy...

Mar 25, 2013 at 1:31 PM | Registered Commentertomo

"Tomo, I too disable Javascript. I use a VM to post here. The thing about trusting people is that you can't..."
Mar 25, 2013 at 1:09 PM | Unregistered CommenterBitBucket

You'll make a fine sceptic yet, BB.

Mar 25, 2013 at 1:54 PM | Unregistered Commentermichael hart

VM? disbaled JS? Proxied IP address? ... BB you are FOIA

Mar 25, 2013 at 2:05 PM | Unregistered CommenterJiminy Cricket

Gras Albert:

Yes, you are right; something is brewing.

Mar 25, 2013 at 2:25 PM | Unregistered CommenterNiels

and as usual, BB derailed the thread. This time, I really do not understand why.

Mar 25, 2013 at 3:14 PM | Unregistered Commenterdiogenes

me neither, perhaps it would be appropriate on Unthreaded, or better still a Propeller Head blog.

Mar 25, 2013 at 4:02 PM | Unregistered CommenterSandyS

I don't trust reported surface temperatures because I understand how the instruments work. I am loathe to trust reported satellite temperatures because I don't understand how the instruments work.

Mar 25, 2013 at 4:08 PM | Unregistered Commenterdearieme

"Aqua AMSU ch. 5 Bites the Dust"

According to Roy's article of today.

Mar 25, 2013 at 4:12 PM | Unregistered CommenterZer0th

"0.8degC is about 4% of 600mb temperature"

So the temperature at 600 MB is 20 K? Actually it is about 250 K and 0.8 degrees is about 0.32 % of that.

Mar 25, 2013 at 5:58 PM | Unregistered Commentertty


So the temperature at 600 MB is 20 K? Actually it is about -20C and 0.8 degrees is about 4 % of that.

Mar 25, 2013 at 7:05 PM | Unregistered CommenterGras Albert

Dr Spencer confirms that Channel 6 & 7 are unaffected by the Channel 5 failure and, together with his plot of the two NOAA satellites AMSU5 shows around 0.4degC fall in troposphere GAT over the past 9 days.

While unusual, a fall of this rate/magnitude in March is not unprecedented, see March 2004 & 2007 for similar events. It will be interesting to watch what happens for the rest of the month.

On an unrelated matter, March CET in the UK is now on target to be the coldest since 1962 and among the coldest five March months for a century

Mar 25, 2013 at 7:23 PM | Unregistered CommenterGras Albert

Asymptotic curve, headed down.

Something's broke.

Mar 25, 2013 at 8:13 PM | Unregistered Commentermojo

The scare is moving on to 'we know that increasingly unpredictable events will increasingly happen'

Mar 25, 2013 at 9:11 PM | Registered CommenterPharos

This is Dr. Spencer's discussion of the problem.

Mar 25, 2013 at 11:54 PM | Unregistered CommenterEntropic man

Gras Albert

The mainland US are also having a late spring.

Mar 26, 2013 at 12:28 AM | Unregistered CommenterEntropic man

Ch #5 is going to spoil the autoscale if they don't do something :-)

Mar 26, 2013 at 12:28 PM | Registered Commentertomo

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