An email exchange with Mojib Latif

The following is an email exchange with  Dr. Mojib Latif, Professor for Climate Physics at the Leibniz Institute of Marine Sciences at Kiel University, concerning his recent work in decadal prediction. My original email was written to draw attention to misrepresentations of Latif’s work and recent comments, as discussed in the immediately following post.

Emails have been placed in chronological order. Certain details have been removed for privacy reasons, or to improve clarity.

=====================================

Subject: Possible misrepresentation in Calgary Herald
Date: Fri, 25 Sep 2009 10:24:52
From: [Deep Climate]
To: Mojib Latif

Dear Dr. Latif,

I am a private citizen with a strong interest in climate change, and have an anonymous blog called deepclimate.org.

I would like to bring to your attention what appears to be a gross distortion of your remarks (probably based on Fred Pearce’s New Scientist account).

Consider the following article by Lorne Gunter in the Calgary Herald (Alberta, Canada):

http://www.calgaryherald.com/business/Scientists%20pull%20about%20face%20global%20warming/2010571/story.html

The following excerpts that appear to exaggerate or distort your comments:

Latif conceded the Earth has not warmed for nearly a decade and that we are likely entering “one or even two decades during which temperatures cool.”
The global warming theory has been based all along on the idea that the Atlantic and Pacific Oceans would absorb much of the greenhouse warming caused by a rise in man-made carbon dioxide, then they would let off that heat and warm the atmosphere and the land.

But as Latif pointed out, the Atlantic, and particularly the North Atlantic, has been cooling instead. And it looks set to continue a cooling phase for 10 to 20 more years.

I have not listened to your remarks to determine if the discussion of Atlantic ocean cooling is accurate, but I am quite certain you did not state that we are “likely” entering “one or even two decades during which temperatures cool.”. That would imply two-thirds probability or greater that the coming decade will be cooler than the last on average. Surely that’s not what you said or meant?

I hope you will consider permitting me to publish your remarks on this on my blog and I would be happy to do so. As well, if you have issued any statements on the New Scientist article, I would be interested in those.

Here are some past pieces I wrote on this same author, Lorne Gunter:

http://deepclimate.org/2009/03/05/lorne-gunter-on-global-cooling-part-1/

http://deepclimate.org/2009/03/10/fact-checking-national-post-style-lorne-gunter-on-global-cooling-part-2/

http://deepclimate.org/2009/04/09/the-alberta-oil-boys-network-spins-global-warming-into-cooling/

Thank you in advance for any assistance you may lend me.

All the best,

[Deep Climate]

========================================

Subject: Re: Possible misrepresentation in Calgary Herald
Date: Sat, 26 Sep 2009 08:26:36
From: Mojib Latif
To: [Deep Climate]

[DC],

what I said is that the cooling in the Atlantic and Pacific may offsset global warming for a decade so that there may be not much of an additional warming. I showed a prediction that was published last year in the science magazine “nature”. I also pointed out that the British group issued a competing forecast for the next decade. They predict that global warming will continue at the rate of the last decades. Thus, and I made this very clear, there is quite some uncertainty about the short-term evolution. Yet we all agree that in the long run, say by 2050 and thereafter,  the earth will considerably warm, if we do not considerably reduce global greenhouse gas emissions.

Mojib.

===========================================

Subject: Re: Possible misrepresentation in Calgary Herald
Date: Sat, 26 Sep 2009 14:07:41 -0700
From: [Deep Climate]
To: Mojib Latif

Mojib,
Thank you for patiently answering my questions.

I would submit that “not much of an additional warming” is very different from  “likely entering ‘one or even two decades during which temperatures cool.’” You should be very concerned, even outraged, at this gross distortion of your findings and views. This article was read by tens of thousands in print and has been disseminated far and wide over the internet.

I would like to confirm the actual projected central estimates from the key figure in your Nature article, using average increases over preceding decade. I have presumed that the levels shown in the figure are for the decade average centred on the particular year marked, so that the value at 2005, for example,  is the average for 2000-2010. If you could confirm or correct these, I would be most obliged. Providing the estimates plus 95% bounds to two significant digits would be even better.

In terms of projected HadCRU anomaly and decade-over-decade difference, I get:

1990-2000:  0.19C
2000-2010:  0.29C  0.10C
2010-2020:  0.47C  0.18C
2020-2030:  0.79C  0.32C

It thus also appears that  your model projects that cooling in 2010-2020 is highly unlikely, as measured by decade-over-decade difference.

Many thanks for any assistance you may lend. I want to get this right, as there is already enough misinformation out there.

Thanks,
[DC]

=========================================

Subject: Re: Possible misrepresentation in Calgary Herald
Date: Sun, 27 Sep 2009 08:42:36
From: Mojib Latif
To: [Deep Climate]

[DC],

this is all correct. However, our forecast more than one decade ahead does not have much skill, as we know from hindcasts (retropsective forecasts). I think what is important to convey is that there are short-term fluctuations which are superimposed on the long-term warming trend.
Mojib.
===========================================
Subject: Re: Possible misrepresentation in Calgary Herald
Date: Sun, 27 Sep 2009 10:48:42
From: [Deep Climate]
To: Mojib Latif

Mojib,
The problem I am trying to overcome is that even when you have been quoted correctly, the time scale has been lost. But the graph clearly shows we are speaking of slowed warming or (less probably) actual cooling up to 2015 only. That’s why I think it is important to have clear central estimates for each decade. The idea that you actually projected less warming for 2000-2010 than for 2010-2020 is a significant piece of information that has been totally lost in the coverage, even amomg well-meaning sincere journalists.

I hope you will permit me to disseminate your remarks in their entirety. I believe that would be very useful in clearing up the misunderstandings in play.

Thanks,
[DC]

========================================

——– Original Message ——–

Subject: Re: Possible misrepresentation in Calgary Herald
Date: Mon, 28 Sep 2009 09:07:41
From: Mojib Latif
To: [Deep Climate]
[DC],
we showed the graph more than a decade ahead to see how long the effect of the initial conditions lasts. It is a forecast, but as I pointed out, we do not have much skill at longer lead times. It may well be that the warming will be even stronger.
Mojib.

========================================

Subject: Re: Possible misrepresentation in Calgary Herald
Date: Tue, 29 Sep 2009 09:04:58
From: [Deep Climate]
To: Mojib Latif

Mojib,
I haven’t heard back from you, so I assume you have no objection to publication of your remarks at deepclimate.org. Still, I would prefer that you respond explicitly giving me permission, so I will wait for now. I probably won’t go ahead and publish your remarks until you respond one way or the other, although I may refer in passing to the fact that we have corresponded and that you broadly confirmed my interpretation of the central estimates of decadal warming in Keenlyside et al.

I believe our exchange is very important and will help correct the misinformation that has been propagated concerning your remarks at WCC in Geneva and Keenlyside et al in general.

I look forward to hearing from you as soon as possible – a simple “Yes, go ahead” would suffice.

Many thanks,
[DC]

==================================================

Subject: Re: Possible misrepresentation in Calgary Herald
Date: Tue, 29 Sep 2009 18:12:29
From: Mojib Latif
To: [Deep Climate]
Please go ahead and publish, [DC].
Mojib.
About these ads