I’ve moved to WordPress: http://bobtisdale.wordpress.com/

Friday, October 9, 2009

Update of NODC (Levitus et al 2009) OHC Data Through June 2009

I’ve moved to WordPress.  This post can now be found at Update of NODC (Levitus et al 2009) OHC Data Through June 2009
###############
UPDATE (October 16, 2009):
This post contains erroneous data that was posted by the NODC at their website. The graphs have been updated in the post "NODC Corrections to Ocean Heat Content (0-700m) Part 3". I have left this post intact for those who wish to compare the graphs of the individual basins.

Earlier updates to this post are now located at the end.

UPDATE (October 11, 2009):
Joe Romm of ClimateProgress noted in his reply to my comment on his post “Skeptical Science explains how we know global warming is happening: It’s the oceans, stupid!”, “Heck you don't even link to the article, which was "published 11 April 2009" (!!) whereas all the data you list is subsequent to that.”

For those who are incapable of clicking on the NODC links that I do provide in the following post and discovering that Levitus et al (2009) is linked there, here’s a direct link to the paper:
ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/PUBLICATIONS/grlheat08.pdf

Note: Joe’s closing clause in the quote above (“…whereas all the data you list is subsequent to that.”) is curious. It reflects his misunderstanding of what I presented or it reflects his attempt to misdirect his readers. Either way, he missed the mark. In the following post, I graphed the updated NODC data that’s available through KNMI. And that’s really all the post is about. It’s an update. Nothing more, nothing less. It includes all of the base Levitus et al (2009) data from January 1955 to December 2008 PLUS the recently released updated data from January 2009 through June 2009. Based on Joe Romm’s reasoning, we should disregard all climate data (SST, TLT, TSI, sea level, etc.) that are posted after the paper that introduces the dataset or maybe Joe is suggesting that all updates need to be peer reviewed.

##########

INTRODUCTION
On October 1, KNMI updated the NODC Ocean Heat Content (Levitus et al 2009) data that’s available on Climate Explorer.
http://climexp.knmi.nl/selectfield_obs.cgi?someone@somewhere

These updates are not shown on the NODC’s Global Ocean Heat Content webpage:
http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/index.html

The updates also aren’t shown in the table of Global Analyzed Fields (ASCII files):
http://www.nodc.noaa.gov/cgi-bin/OC5/3M_HEAT/heatdata.pl?time_type=yearly700

But the single 22.4 MB dataset at the top of the table does contain the January through March and the April through June data, which were updated (added) on September 14, 2009:
ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/DATA_ANALYSIS/3M_HEAT_CONTENT/DATA/heat_3month/HC_0-700-3month.tar.gz

GLOBAL, HEMISPERIC, AND OCEAN BASIN GRAPHS

Global OHC has dropped back to its 2003 levels.


http://i34.tinypic.com/dev5ld.png
Global OHC

North Atlantic OHC is continuing to decline from its 2004 peak.
http://i36.tinypic.com/ddkeas.png
North Atlantic OHC

The recent drop in the South Atlantic OHC was sizeable, but not outside of the range of its normal variability.
http://i36.tinypic.com/2m5fais.png
South Atlantic OHC

And of the remaining OHC datasets, the only two that showed increases over the past six months are the South Pacific and Southern Ocean OHC
http://i35.tinypic.com/1ys415.png
South Pacific
############
http://i38.tinypic.com/34f19p2.png
Southern Ocean

Here are the remaining OHC subsets without commentary.
http://i38.tinypic.com/j79h1i.png
Northern Hemisphere
############
http://i35.tinypic.com/cqr13.png
Southern Hemisphere
############
http://i37.tinypic.com/2wlxz09.png
North Pacific
############
http://i38.tinypic.com/6e0oax.png
Indian Ocean
############
http://i38.tinypic.com/9u417d.png
Arctic Ocean

CLOSING
Two earlier posts illustrated the impacts of natural variables on OHC. These included the ENSO-induced step changes in the OHC of numerous oceans and the effects of the NAO on high-latitude North Atlantic OHC:

1. ENSO Dominates NODC Ocean Heat Content (0-700 Meters) Data
2. North Atlantic Ocean Heat Content (0-700 Meters) Is Governed By Natural Variables
UPDATE (October 11, 2009):
Joe Romm of ClimateProgress noted in his reply to my comment on his post “Skeptical Science explains how we know global warming is happening: It’s the oceans, stupid!”, “Heck you don't even link to the article, which was "published 11 April 2009" (!!) whereas all the data you list is subsequent to that.”
For those who are incapable of clicking on the NODC links that I do provide in the following post and discovering that Levitus et al (2009) is linked there, here’s a direct link to the paper:
ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/PUBLICATIONS/grlheat08.pdf
Note: Joe’s closing clause in the quote above (“…whereas all the data you list is subsequent to that.”) is curious. It reflects his misunderstanding of what I presented or it reflects his attempt to misdirect his readers. Either way, he missed the mark. In the following post, I graphed the updated NODC data that’s available through KNMI. And that’s really all the post is about. It’s an update. Nothing more, nothing less. It includes all of the base Levitus et al (2009) data from January 1955 to December 2008 PLUS the recently released updated data from January 2009 through June 2009. Based on Joe Romm’s reasoning, we should disregard all climate data (SST, TLT, TSI, sea level, etc.) that are posted after the paper that introduces the dataset or maybe Joe is suggesting that all updates need to be peer reviewed.
##########

UPDATE 2 (October 11, 2009):
Those of you who read my comment at Joe Romm’s ClimateProgress…
http://climateprogress.org/2009/10/10/skeptical-science-global-warming-not-cooling-is-still-happening-ocean-heat-content/comment-page-1/#comment-155154
…will note that I referred to my earlier reply to dhogaza. Hmmm. Not too surprisingly, that comment never made it to the thread. Having posted comments there before and having had them deleted, I now keep copies. Here’s what I wrote:

8. Bob Tisdale says:
Your comment is awaiting moderation.
October 11, 2009 at 5:21 am

dhogaza: I presume your remark (3.) “Lessee… MIT-trained physicist vs. a high-school trained weather reader. I wonder which is more likely to understand the science” is to tallbloke (2.) above, in which he included a link to the WUWT post that I wrote. My original version is here:
http://bobtisdale.blogspot.com/%202009/%2010/%20update-of-nodc-levitus-et-al-2009-ohc.html
If not, disregard this comment.

That post uses NODC OHC data. As noted above, it shows a drop in OHC from January 2009 to June 2009. It was prepared as part of Levitus et al (2009):
ftp://ftp.nodc.noaa.gov/%20pub/%20data.nodc/%20woa/%20PUBLICATIONS/%20grlheat08.pdf
I don’t believe there’s a “high-school trained weather reader” among S. Levitus, J. I. Antonov, T. P. Boyer, R. A. Locarnini, H. E. Garcia, and A. V. Mishonov.

Their update is available here:
ftp://ftp.nodc.noaa.gov/%20pub/%20data.nodc/%20woa/%20DATA_ANALYSIS/%203M_HEAT_CONTENT/%20DATA/%20heat_3month/%20HC_0-700-3month.tar.gz

If you can’t work with the NODC’s Global Analyzed Fields above, the data is also available on a more user-friendly basis through the KNMI Climate Explorer:
http://climexp.knmi.nl/%20selectfield_obs.cgi?someone@somewhere
Simply scroll down to “Heat content” and select “1955-now: NODC 0-700m”.

If the drop in OHC concerns you, I suggest you contact Levitus et al. After you explain why you called them high school-trained weather readers, I’m sure they’ll be happy to answer your questions.

Have a nice day.

18 comments:

John said...

This is rather significant, no? I remember a posting on Pielke Sr.'s website that Hansen et al expected a continuously increasing OHC as a marker of AGW.

A flattening was one thing, but a decrease? That really seems to fly in the face of Hansen's belief of the ocean as a store of GHG-influenced heat, right?

Sorry if I am misreading, and thank you, as always, for the post.

Bob Tisdale said...

John: You're not misreading. The recent drop in global OHC is significant, as is the multiyear drop in the North Atlantic OHC.

Anonymous said...

This data seems to contradict the recent update of Shuckmann et al. (2009, http://tinyurl.com/ygt782h ), who calculate OHC using the full ARGO data down to 2000m.
One can see their plot here: http://tinyurl.com/yj458te

Was this previous data only using ARGO down to 700m? If so, I think that might be significant, as some new observations are showing that the deepwaters are actually warming, and that 700m may not be sufficient to measure OHC.

Alessandro Patrignani said...

Thank yo Bob, great post ! I reported the same data from Climate Explorer in my italian language Blog and I mentioned you: http://globalwarming.blog.meteogiornale.it/2009/10/10/il-dato-piu-importante-per-il-gw-lohca-review/

I think it's really important, for the Arctic, the OHCA reducing in NAtl area (as AMO too). I suggest you looking at the study I mentioned on this post: http://globalwarming.blog.meteogiornale.it/2009/10/01/artico-il-minimo-del-2007-e-la-corrente-west-spitzbergen/

Ciao.

Bob Tisdale said...

Anonymous: You wrote, "This data seems to contradict the recent update of Shuckmann et al. (2009, http://tinyurl.com/ygt782h ), who calculate OHC using the full ARGO data down to 2000m."

I'm not sure how YOU can visually compare a graph of OHC from January 1950 to June 2009 to a graph of OHC from January 2003 to December 2008 and find that the two contradict one another.

Here's a graph of the NODC Global OHC data from 2003 to 2008. It shows an upward trend.
http://i33.tinypic.com/2ynq7v8.png
But when you include the past six months, the trend flattens:
http://i38.tinypic.com/300d3dl.png

You asked, "Was this previous data only using ARGO down to 700m?"

ARGO float deployment began in 2000, but there are a number of problems with the data. Refer to the ARGO webpage here:
http://www.argo.ucsd.edu/global_change_analysis.html

They write, "The global Argo dataset is not yet long enough to observe global change signals. Seasonal and interannual variability dominate the present 5-year globally-averaged time series. Sparse global sampling during 2004-2005 can lead to substantial differences in statistical analyses of ocean temperature and trend (or steric sea level and its trend, e.g. Leuliette and Miller, 2009). Analyses of decadal changes presently focus on comparison of Argo to sparse and sometimes inaccurate historical data. Argo's greatest contributions to observing the global oceans are still in the future, but its global span is clearly transforming the capability to observe climate-related changes."

You wrote, "If so, I think that might be significant, as some new observations are showing that the deepwaters are actually warming, and that 700m may not be sufficient to measure OHC."

The problem is data availability. The further back in time you go, the less temperature-at-depth readings there are.

Bob Tisdale said...

Alessandro: Thanks for the acknowledgement and the links.

lucia said...

Very interesting!

Mike M. said...

I had to laugh. Normally, you are as close to a Vulcan as there is in this discussion. Joe Romm is so irritating he even gets under your skin. Joe Romm is so irritating, he must be a Karl Rove plant sent to help ruin the AGW movement!

Keep up the great work, Bob.

John said...

Bob -

Do you know if this drop is reflected in the other non-Levitus data sets (which had showed lower OHC than Levitus?) Domingues, etc?

Bob Tisdale said...

John: I have not seen any other 2009 OHC data. It's not to say it doesn't exist.

Bob Tisdale said...

Lucia: I'm honored by your visit.

Bob Tisdale said...

Mike M: I assume being close to a Vulcan is a good thing. And, yes, Joe's comment was...enlightening.

Anonymous said...

Ah, thank you for the zoomed in plots. That's a very interesting drop. It will be interesting to see what evolves over the next 6 months and if it is also reflected in the other data sets.

tallbloke said...

Hi Bob, looks like my crayon remark stirred Joe's braincell around a bit eh? ;-)

May you blog long and prosper.

tallbloke said...

Hi Bob,
according to Cazenave et al 2008, the steric component of sea level has been dropping since 2006:

Ocean Heat content:
Sea Level Budget over 2003–2008: A Reevaluation from GRACE Space Gravimetry, Satellite Altimetry and Argo by Cazenave et al. 2008

http://sciences.blogs.liberation.fr/home/files/Cazenave_et_al_GPC_2008.pdf

“The steric sea level estimated from the difference between altimetric (total) sea level and ocean mass displays increase over 2003-2006 and decrease since 2006. On average over the 5 year period (2003-2008), the steric contribution has been small (on the order of 0.3+/-0.15 mm/yr), confirming recent Argo results (this study and Willis et al., 2008).”

Bob Tisdale said...

tallbloke: Thanks for the Cazenave et al 2008 link. I know just where to use it. Nope, not ClimateProgress. It'll be useful at Accuweather on a two- or three-day-old thread. Thanks again.

Unknown said...

i tried to replicate the global result, and while i can roughly match your result from 2000-2008, the 2009 data isn't showing cooling:

http://www.scriptkiddie.org/2009ohc.png

Bob Tisdale said...

lamont: Refer to the October 16 update at the top of the page. It reads:

This post contains erroneous data that was posted by the NODC at their website. The graphs have been updated in the post "NODC Corrections to Ocean Heat Content (0-700m) Part 3". I have left this post intact for those who wish to compare the graphs of the individual basins.

The link to the updated graphs is here:
http://bobtisdale.blogspot.com/2009/10/nodc-corrections-to-ocean-heat-content_16.html

Donations

Tips are now being accepted.

Comment Policy, SST Posts, and Notes

Comments that are political in nature or that have nothing to do with the post will be deleted.
####
The Smith and Reynolds SST Posts DOES NOT LIST ALL SST POSTS. I stopped using ERSST.v2 data for SST when NOAA deleted it from NOMADS early in 2009.

Please use the search feature in the upper left-hand corner of the page for posts on specific subjects.
####
NOTE: I’ve discovered that some of the links to older posts provide blank pages. While it’s possible to access that post by scrolling through the history, that’s time consuming. There’s a quick fix for the problem, so if you run into an absent post, please advise me. Thanks.
####
If you use the graphs, please cite or link to the address of the blog post or this website.