Saturday, July 17, 2010

Hotting up?

Following on from this post, the latest headlines on hot global temperatures are a bit surprising to me. The Torygraph reports that the first half of the year was the hottest Jan-June on record, surpassing even 1998. The headline to that article is forecasting a new record for the whole year too, but the person quoted seems rather less confident of that. This is all based on the NCDC analysis, not HadCRUT which I've bet on. Neither is it GISS which has the well-known polar extrapolation, though, so I'm not sure why it is quite so hot. The pattern of temperature anomalies on the Grauniad page also doesn't really look much like an ENSO pattern (to my inexpert eye at least), with warming pretty much everywhere apart from the Eastern Pacific.


Steve Bloom said...

Here's the source document.

crandles said...

I estimate the probability at just over 50% of 2010 being warmest based on this record so I think 'on course' is quite acceptable. "Expected" might be pushing it a little so "it's possible that we will not" seems a sensible caveat.

The map is versus 1971-2000 base period rather than ENSO neutral or conditions 6 months earlier. So perhaps it isn't surprising that it is relatively hot in most places?

Looks like you may have accepted the wrong record to bet on.

James Annan said...

Thanks for the link Steve.

Chris, I agree hot in most places is not unexpected, but the pattern is if anything la-nina like, which is normally associated with relative cold. OTOH given the lag between enso and global mean temp, I suppose the enso pattern itself is not so strongly linked to warmth.

My big bet with the russians is actually based on this data set IIRC. Though I'm looking like winning that comfortably enough on all data sets - except perhaps tree rings :-)

crandles said...

Well it is of June 2010 when the ONI index is approx -0.47 so it is of very early in a La Nina pattern. I think the temperature effects at the start should show strongly in the Nino regions. Later on, the effects spread out to lots of other regions.

The following is the map from June 2009 when the recent El Nino had just started:

That shows more like an El Nino pattern. So to me it looks like these do show the expected patterns.

crandles said...

The weekly ONI for nino 3.4 region is down to -1.

So my previous "Assuming MEI for May/June is -0.2 and for the rest of the year -0.5 seems quite optimistic assumptions for you." is definitely looking too optimistic.

Using -1 as the MEI estimate for the rest of the year: Now out of 40 years, 2 years were warmer than the multiple linear regression estimate by sufficient and 1 year got close. So this suggests it might only be a 10% for James this year.

Brian said...

"My big bet with the russians is actually based on this data set IIRC."

You do indeed RC:

Given the research scientist mega-salaries that I keep hearing about from skeptics, I'm not surprised that you're hazy about the details over a mere $10k.

EliRabett said...

His wife works. OTOH she has a knitting habit.

skanky said...

Do the Japanese not do a free needle programme?

Hank Roberts said...

psst -- your move, I believe.
Though your opponent's time-traveling citation ploy failed to impress, so I could understand if you left the game.

Hank Roberts said...

Oh, never mind, she'll find you in the journals:

".... our understanding and characterization of the uncertainties surrounding climate change is inadequate. I am currently completing a journal article ....

.... our current projections of 21st climate change erroneously anchor to a range that is too narrow.... A key failure of the current IPCC strategy is inadequate attention to characterizing the plausible worst case scenario .... How this issue should be addressed is also covered in the new paper i am working on...."

Steve Bloom said...

"How this issue should be addressed is also covered in the new paper i am working on...."

Phew, that was close. If any more time had gone by Jules and James would be forced to do all that work they... kind of already did.

OTOH I'm sure James and everyone else in the field will appreciate Judy's fresh new perspective.

I'll predict now that Judy's treatment of the worst-case scenario will be mainly in the service of flogging a best-case scenario based on very low sensitivity.

James Annan said...

If she had a fresh perspective, I'd certainly be interested - and I don't completely rule out the possibility a priori. However, to date I've been very disappointed with her purported "third way" which, as many have noted, seems to consist of channeling standard sceptic myths under a tissue-thin veneer of deniability which she uses to run away when challenged.

I'm certainly not averse to a bit of well-aimed criticism of the IPCC and may present some more of my own shortly...

Hank Roberts said...

Please. Someone should organize and help footnote the outside-critics commentariat, it's about time. Please include links to the various points in the develoment toward the 5th report where outside comments were solicited, and any further opportunities that are coming up.

Extra points for organization that matches the IPCC's outline format, for ease of xreference.

If the outside comments can be kept timely, well cited to facts, and well correlated with what's really happening, that would be really helpful and teach all us outside amateurs a lot about what's going on and how it's being done this time.
I recommend you try to get Kate from Climatesight to moderate such a forum, if she doesn't have any other plans for the next few years. She's very good at moderation.

(No, I'm not going to do anyblog of the sort myself. I've got 50 acres of wildland restoration work to pursue, as my first priority

Of course, good moderation would leave the people who want to post outdated claims, uncited beliefs, and fantasy scenarios to go somewhere else for their traditional shitstorm-in-a-wind-farm mess.

Hank Roberts said...


which says in part:
would be interested to see what mathematicians and physicists here make out of this debate on the science side:

• Annan and Hargreaves, Using multiple observationally-based constraints to estimate climate sensitivity, Geophys. Res. Lett., 33, L06704, (and comment by author who has a useful blog with climate posts interspersed with photos)