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

Monday, February 28, 2011

PRELIMINARY February 2011 SST Anomaly Update

I’ve moved to WordPress.  This post can now be found at PRELIMINARY February 2011 SST Anomaly Update
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The February 2011 Reynolds OI.v2 Sea Surface Temperature (SST) data through the NOAA NOMADS website won’t be official until March 7th. Refer to the schedule on the NOAA Optimum Interpolation Sea Surface Temperature Analysis Frequently Asked Questions webpage. The following are the preliminary Global and NINO3.4 SST anomalies for February 2011 that the NOMADS website prepares based on incomplete data for the month. I’ve also included the weekly data through February 23, 2011, but I’ve shortened the span of the weekly data, starting it in January 2004, so that the variations can be seen.

PRELIMINARY MONTHLY DATA

Monthly NINO3.4 SST anomalies reached their seasonal low in January and began the rebound in February. Based on the preliminary data they’re at -1.28 deg C.

http://i53.tinypic.com/11949xj.jpg
Monthly NINO3.4 SST Anomalies
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Monthly Global SST anomalies, according to the preliminary data, have rebounded after their drop last month. The preliminary global SST anomaly is +0.093 deg C.
http://i51.tinypic.com/9argaa.jpg
Monthly Global SST Anomalies
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WEEKLY DATA

The weekly NINO3.4 SST anomalies for the week centered on February 23, 2011 are -1.25 deg C.
http://i56.tinypic.com/1zftnpl.jpg
Weekly NINO3.4 SST Anomalies
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Weekly Global SST Anomalies are presently at +0.11 deg C.
http://i55.tinypic.com/e87gv6.jpg
Weekly Global SST Anomalies
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SOURCES

SST anomaly data is available through the NOAA NOMADS website:
http://nomad1.ncep.noaa.gov/cgi-bin/pdisp_sst.sh
or:
http://nomad3.ncep.noaa.gov/cgi-bin/pdisp_sst.sh?lite=

Thursday, February 24, 2011

Request for Assistance In Assessing an Important Sea Level Study

I’ve moved to WordPress.  This post can now be found at Request for Assistance In Assessing an Important Sea Level Study
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Guest Post by John Droz, Jr.

Friends:

I am asking for help from oceanographers and/or others who have experience with sea level measurements.

I am a physicist (energy expert) who has been involved with several environmental issues over the last thirty years.

I am a traditional scientist in that I am a strong advocate of subjecting hypothesis for solutions to our environmental issues to the Scientific Method. In other words, I would expect that proposed solutions have a comprehensive, independent, transparent and empirical based assessment. (Unfortunately, this now seems to be the minority view among scientists.)

I have written extensively on energy issues, and have given free presentations in some ten states. This is online at EnergyPresentation.Info. There are also several slides about AGW.
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Anyway, the case at hand is that I was recently asked by my local representatives for some scientific assistance.

The brief story is that North Carolina is attempting to be the first state in the nation to impose rather comprehensive and consequential (i.e. expensive) rules and regulations on its coastal communities. This is based on projected substantially increased sea levels, due to the assumed effects of AGW.

But it’s worse than that. The basis for these changes is a 2010 NC Sea Level Assessment Report (http://tinyurl.com/69nzem8).

I have been told that the US federal government funded this study. The stated intention was that they would like that this study be used by the rest of the coastal states (plus the federal government) as a basis for new rules and regulations. If this came about as planned, there would clearly be worldwide implications to this simple report.

As such, it is my view, that it is imperative to get it right.

In my reading of the report, the key assumptions are that:
1 - the IPCC sea level rise projections (15± inches by 2100) are the minimum expected, and
2 - that Rahmstorf (2007: http://tinyurl.com/3bhuzd), is a credible source to use as a high end (55± inches by 2100).

To give the appearance of being reasonable, the report authors (13 esteemed scientists) selected a value near the middle of these numbers: 39± inches by 2100.

Figure 2 (page 11) and the accompanying text in the report shows and explains this.

This is not my area of expertise, so I can not make a technical critique of Rahmstorf's work, or the referenced Church & White (2006) report. If anyone can provide some scientific evidence, pro or con, regarding these documents, it would be greatly appreciated.

Again, what happens about this in NC will likely be a precursor to other coastal states (and countries), so this is an international big deal.

Feel free to email me directly at "aaprjohn@northnet.org".

THANK YOU!

john droz, jr.
physicist & environmental advocate
Morehead City, NC

Sunday, February 20, 2011

The Recent Drop In The Sea Surface Temperatures Of U.S. Coastal Waters

I’ve moved to WordPress.  This post can now be found at The Recent Drop In The Sea Surface Temperatures Of U.S. Coastal Waters
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This post illustrates the recent drop in the SST anomalies of the U.S. coastal waters. We’ll represent this subset with the coordinates of 20N-50N, 130W-65W. I’ve used those coordinates in at least one earlier post about the SST Anomalies of U.S. “Coastal” Waters. Figure 1 is the December 2010 Reynolds OI.v2 SST anomaly map with those coordinates highlighted. The cooling appears to be an exaggerated response to the 2010/11 La Niña.
http://i51.tinypic.com/ny902e.jpg
Figure 1

Figure 2 is the Reynolds OI.v2-based time-series graph for this subset. After the two-month flattening in September and October 2010, at approximately -0.24 deg C, the SST anomalies dropped more than 0.65 deg C by January 2011. The January 2011 reading for the U.S. Coast Waters is the lowest on record for the satellite-based Reynolds Oi.v2 SST dataset.
http://i55.tinypic.com/2hqe9hu.jpg
Figure 2

Note: This is not a post about global sea surface temperature (SST) anomalies, nor is it a post about the SST anomalies of the individual ocean basins. For those refer to the January 2011 SST Anomaly Update.

Figures 3, 4, and 5 show the long-term SST anomalies for the U.S. Coastal Waters using the HADISST, ERSST.v3b, and HADSST2 datasets. They provide a different perspective on the magnitude of the recent drop. For the HADISST and ERSST.v3b datasets, one has to go back to the April 1971 to find similar SST anomalies, and back to July 1933 with HADSST2 data.
http://i53.tinypic.com/339o96f.jpg
Figure 3
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http://i54.tinypic.com/30w5e6v.jpg
Figure 4
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http://i56.tinypic.com/29e54s6.jpg
Figure 5

The weekly data for this subset, Figure 6, show that the SST anomalies are rebounding. I’ll add this dataset to the monthly update for a few months to assure it rebounds fully.
http://i52.tinypic.com/11lmsuw.jpg
Figure 6

SOURCE
The map and all data presented in this post are available through the KNMI Climate Explorer:http://climexp.knmi.nl/selectfield_obs.cgi?someone@somewhere

Thursday, February 17, 2011

GISS Has Removed ERSST.v3b As An Option On Its Map-Making Webpage

I’ve moved to WordPress.  This post can now be found at GISS Has Removed ERSST.v3b As An Option On Its Map-Making Webpage
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I had noted the addition of ERSST.v3b SST dataset to the GISS Global Maps webpage almost a year ago in the February 25, 2010 post WHEN DID GISS ADD ERSST.v3b DATA TO THEIR MAP-MAKING WEB PAGE? In a follow-up post a month later, GISS Acknowledges Addition of ERSST.v3b Data To Their GISTEMP Options, I provided a link to the draft of Hansen et al (2010) which explained the reason for the inclusion of the ERSST.v3b data on its website, even though GISS uses a combination of HADISST and Reynolds OI.v2 SST data in their GISS Land-Ocean Temperature Index (LOTI) dataset. Basically, GISS was evaluating the two SST datasets (and awaiting additional analysis), but they would continue to use the combined HADISST/Reynolds OI.v2 data “unless and until verifications show ERSST to be superior.”

Hansen et al (2010) was published on December 10, 2010, “Global surface temperature change”. [Rev. Geophys., 48, RG4004, doi:10.1029/2010RG000345] (PDF). Then, approximately two months later, GISS removed ERSST.v3b SST data as an option on its map-making webpage. See Figure 1.

http://i56.tinypic.com/10cj3bs.jpg
Figure 1

This of course raises a number of questions. Does it mean that “verifications” did not “show ERSST to be superior”? If so, in what publication was this presented? Or was the webpage simply updated incorrectly and the update failed to include the ERSST.v3b option in the drop-down menu?

Monday, February 14, 2011

NINO3.4 SST Anomalies Have Started Their La Niña Rebound

I’ve moved to WordPress.  This post can now be found at NINO3.4 SST Anomalies Have Started Their La Niña Rebound
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Figure 1 shows weekly NINO3.4 SST anomalies from January 7, 2004 through February 9, 2011. The central equatorial Pacific SST anomalies have risen significantly in the last week.
http://i51.tinypic.com/epnha9.jpg
Figure 1

Figure 2 compares the SST anomalies for the transitions from El Niño to La Niña events, during the years of 1988/89, 1998/99, 2007/08, and 2010 through February 9, 2011. At first glance, it appears this rebound started early, but the rebound from the 1988/89 La Niña actually started rising from its minimum a few weeks earlier.
http://i51.tinypic.com/14x2mmr.jpg
Figure 2

And since we’re looking at weekly data, Figure 3 shows the Global SST anomalies from January 7, 2004 through February 9, 2011.
http://i56.tinypic.com/213403k.jpg
Figure 3

SOURCE
The Optimally Interpolated Sea Surface Temperature Data (OISST) are available through the NOAA National Operational Model Archive & Distribution System (NOMADS).
http://nomad1.ncep.noaa.gov/cgi-bin/pdisp_sst.sh
or
http://nomad3.ncep.noaa.gov/cgi-bin/pdisp_sst.sh

Monday, February 7, 2011

January 2011 SST Anomaly Update

I’ve moved to WordPress.  This post can now be found at January 2011 SST Anomaly Update
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MONTHLY SST ANOMALY MAP

The map of Global OI.v2 SST anomalies for January 2011 downloaded from the NOMADS website is shown below. There was a mix of variations in ocean basin SST anomalies this month. The Arctic, South Atlantic, and South Pacific rose; the rest fell. The result was a decrease in global SST anomalies (-0.033 deg C). They are presently at +0.067 deg C.

Note the pattern in the Pacific. It is not a typical La Niña pattern. Note also the elevated anomalies in mid-latitude South Atlantic and in the South Pacific, in what could be described as an extension of the South Pacific Convergence Zone (SPCZ).

http://i54.tinypic.com/33wm8ly.jpg
January 2011 SST Anomalies Map (Global SST Anomaly = +0.067 deg C)

MONTHLY OVERVIEW

Monthly NINO3.4 SST anomalies are still varying at or near the seasonal low for this La Niña. The Monthly NINO3.4 SST Anomaly is -1.59 deg C.

The drop in Northern Hemisphere this month (-0. 060 deg C) is significantly larger than the Southern Hemisphere (-0.011 deg C). Globally, there was a healthy decline (-0.033 deg C).
http://i53.tinypic.com/ic7pzd.jpg
Global
Monthly Change = -0.033 deg C
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http://i52.tinypic.com/11lhg86.jpg
NINO3.4 SST Anomaly
Monthly Change = -0.063 deg C

EAST INDIAN-WEST PACIFIC
The SST anomalies in the East Indian and West Pacific took a major nose dive this month.

I’ve added this dataset in an attempt to draw attention to what appears to be the upward steps in response to significant El Niño events that are followed by La Niña events.
http://i51.tinypic.com/rsv7nn.jpg
East Indian-West Pacific (60S-65N, 80E-180)
Monthly Change = -0.171 deg C

Further information on the upward “step changes” that result from strong El Niño events, refer to my posts from a year ago Can El Niño Events Explain All of the Global Warming Since 1976? – Part 1 and Can El Niño Events Explain All of the Global Warming Since 1976? – Part 2

And for the discussions of the processes that cause the rise, refer to More Detail On The Multiyear Aftereffects Of ENSO - Part 2 – La Niña Events Recharge The Heat Released By El Niño Events AND...During Major Traditional ENSO Events, Warm Water Is Redistributed Via Ocean Currents -AND- More Detail On The Multiyear Aftereffects Of ENSO - Part 3 – East Indian & West Pacific Oceans Can Warm In Response To Both El Niño & La Niña Events

The animations included in post La Niña Is Not The Opposite Of El Niño – The Videos further help explain the reasons why East Indian and West Pacific SST anomalies can rise in response to both El Niño and La Niña events.

NOTE ABOUT THE DATA
The MONTHLY graphs illustrate raw monthly OI.v2 SST anomaly data from December 1981 to January 2011.

MONTHLY INDIVIDUAL OCEAN AND HEMISPHERIC SST UPDATES http://i55.tinypic.com/2utgoav.jpg
Northern Hemisphere
Monthly Change = -0.060 deg C
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http://i53.tinypic.com/2a9y73a.jpg
Southern Hemisphere
Monthly Change = -0.011 deg C
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http://i55.tinypic.com/f06irn.jpg
North Atlantic (0 to 75N, 78W to 10E)
Monthly Change = -0.002 deg C
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http://i51.tinypic.com/11ke0dz.jpg
South Atlantic (0 to 60S, 70W to 20E)
Monthly Change = +0.054 deg C

Note: I discussed the upward shift in the South Atlantic SST anomalies in the post The 2009/10 Warming Of The South Atlantic. It does not appear as though the South Atlantic will return to the level it was at before that surge. That is, it appears to have made an upward step.

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http://i53.tinypic.com/r6wyms.jpg
North Pacific (0 to 65N, 100 to 270E, where 270E=90W)
Monthly Change = -0.053 Deg C
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http://i53.tinypic.com/v6rucg.jpg
South Pacific (0 to 60S, 145 to 290E, where 290E=70W)
Monthly Change = +0.021 deg C
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http://i51.tinypic.com/wcnthv.jpg
Indian Ocean (30N to 60S, 20 to 145E)
Monthly Change = -0.135 deg C
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http://i55.tinypic.com/35jvx37.jpg
Arctic Ocean (65 to 90N)
Monthly Change = +0.013 deg C
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http://i55.tinypic.com/2vb0y0x.jpg
Southern Ocean (60 to 90S)
Monthly Change = -0.046 deg C

WEEKLY SST ANOMALIES



The weekly NINO3.4 SST anomaly data portray OI.v2 data centered on Wednesdays. The latest weekly NINO3.4 SST anomalies are -1.49 deg C.
http://i56.tinypic.com/nby7wl.jpg
Weekly NINO3.4 (5S-5N, 170W-120W)
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The weekly global SST anomalies are at +0.080 deg C.
http://i53.tinypic.com/al6zis.jpg
Weekly Global

SOURCE
The Optimally Interpolated Sea Surface Temperature Data (OISST) are available through the NOAA National Operational Model Archive & Distribution System (NOMADS).
http://nomad1.ncep.noaa.gov/cgi-bin/pdisp_sst.sh
or
http://nomad3.ncep.noaa.gov/cgi-bin/pdisp_sst.sh

Thursday, February 3, 2011

Comments On Tamino’s AMO Post

I’ve moved to WordPress.  This post can now be found at Comments On Tamino’s AMO Post
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UPDATE (3-16-11): Refer to the update at the end of the post.

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Tamino’s AMO post is a response to my post Removing The Effects of Natural Variables - Multiple Linear Regression-Based or “Eyeballed” Scaling Factors (hereinafter referred to as the “Removing” post). Tamino took exception to my inclusion of the AMO as one of the datasets used to explain the rise in GISS Land-Ocean Temperature Index (60S-60N) during the satellite era. Please read Tamino’s AMO post before continuing.

My “Removing” post, as discussed in its opening paragraph, was the second in a series follow-ups to the earlier post Can Most Of The Rise In The Satellite-Era Surface Temperatures Be Explained Without Anthropogenic Greenhouse Gases? (hereinafter referred to as the “Can Most” post). The first follow-up was Notes On Polar Amplification.

And for those new to the Atlantic Multidecadal Oscillation (AMO) refer to the post An Introduction To ENSO, AMO, and PDO -- Part 2.

THE REAL CLIMATE DESCRIPTION OF THE AMO

Tamino wrote in his post, “Bob Tisdale (and others) simply can’t wrap their brains around the fact that global warming is the cause, not the effect, of much of the changes in N.Atl SST anomaly. Therefore global warming is the cause, not the effect, of much of the variation in the AMO.”

My AMO posts typically include the RealClimate description of the Atlantic Multidecadal Oscillation (“AMO”), but I failed to include it in “Removing” post. RealClimate states, “A multidecadal (50-80 year timescale) pattern of North Atlantic ocean-atmosphere variability whose existence has been argued for based on statistical analyses of observational and proxy climate data, and coupled Atmosphere-Ocean General Circulation Model (“AOGCM”) simulations. This pattern is believed to describe some of the observed early 20th century (1920s-1930s) high-latitude Northern Hemisphere warming and some, but not all, of the high-latitude warming observed in the late 20th century. The term was introduced in a summary by Kerr (2000) of a study by Delworth and Mann (2000).”

Tamino’s opinion contradicts the opinions of his associates at RealClimate, or at least the opinion of the author of the RealClimate AMO webpage. RealClimate describes the AMO as being responsible for some, but not all, of the warming, but Tamino states it’s the other way around, that the global warming signal is the cause of the AMO variability.

Tamino’s RealClimate associates must be among “the others” who “simply can’t wrap their brains around the fact that global warming is the cause, not the effect, of much of the changes in N.Atl SST anomaly.”

A NOTE ABOUT THE SST DATASET USED IN THIS POST
GISS uses two SST anomaly datasets in its Land-Ocean Temperature (LOTI) product: HADISST from January 1880 to November 1981 and Reynolds OI.v2 from December 1981 to present. There is little difference between the HADISST and Reynolds OI.v2 data for the North Atlantic during the satellite era, as shown in Figure 1. So my use of HADISST data in the short-term will not influence the results of this post.

http://i52.tinypic.com/fxyvwp.jpg
Figure 1

However, there is a significant difference between the long-term Kaplan North Atlantic SST data used by the ESRL (and Tamino) and the HADISST data used by GISS. Refer to Figure 2. Keep in mind my use of the ESRL data was only for the AMO index in the short term, not the long-term SST data used by Tamino. (Note: I confirmed via email that the ESRL uses the coordinates of 0-70N and 80W-0 for its AMO data.)
http://i51.tinypic.com/28atkzb.jpg
Figure 2

And the difference does impact Tamino’s post. He uses the wrong North Atlantic SST anomaly dataset when he subtracts global temperatures from it. That is, assuming Tamino did not switch to the HADISST version of the North Atlantic, he biased the results in his last graph by the difference in the trends of the HADISST data (used by GISS) and the Kaplan data (used by ESRL) shown in Figure 2.

ON THE NONLINEARITY OF THE WARMING SIGNAL

The natural multidecadal variability of the North Atlantic SST anomalies is significantly greater than that of the Global (90S-90N) SST anomalies. This is very apparent if we compare detrended North Atlantic SST anomalies (AMO) to detrended Global SST data, Figure 3. The data have been smoothed with a 121-month running-average filter.
http://i54.tinypic.com/xnuvbq.jpg
Figure 3

Tamino opens his post with a discussion of the how the AMO is calculated by detrending North Atlantic SST anomalies, and he notes that the Wikipedia definition warns about the nonlinearity of the actual warming signal. The nonlinearity of the detrended global SST signal is shown clearly in my Figure 5 above. Based on his presentation, Tamino concludes, “Variations in the forced signal do leak into the AMO definition.”

Let’s compare the short-term linear trends of the North Atlantic SST anomalies to the trends of the other ocean basins. This is a general discussion of the AMO, so I’ve left in the Arctic and Southern Ocean data. Keep in mind that my “Removing” and “Can Most” posts only dealt with the period starting in 1982, which is the satellite era for SST data. As shown in the spaghetti graph, Figure 4, the SST anomaly linear trend of the North Atlantic is significantly higher than all other SST basins. The linear trend of the Arctic Ocean SST anomalies comes in second, in part because those two datasets overlap and due to the influence of the North Atlantic on the Arctic Ocean. Regardless, the North Atlantic linear trend is almost twice that of the Arctic Ocean. The North Atlantic trend is more than 3 times higher than the trends of the North Pacific and Indian Oceans and more than 5 times higher than the trends of the South Atlantic and South Pacific. And of course, the Southern Ocean linear trend is negative. (Note: The impact of the Southern Ocean cooling is so substantial that the trend is basically flat for all HADISST anomaly data south of 40S, or about 35% of the global oceans, since 1982.)
http://i56.tinypic.com/vo0ck0.jpg
Figure 4

This difference in linear trends can also be seen in the comparison of North Atlantic SST anomalies and the SST anomalies for the rest of the world. To determine the rest-of-the-world data (identified as “Global Without No Atlantic” in Figure 5), I approximated the North Atlantic surface area as a percentage of the global oceans. The Atlantic represents approximately 30% of the surface area of the global oceans. I assumed the North Atlantic made up half of that, or 15%, before scaling the North Atlantic data and subtracting it from the global data for Figure 5. The linear trend of the North Atlantic SST anomalies is more than 5 times greater than the average of the other ocean basins.
http://i53.tinypic.com/ml1jz9.jpg
Figure 5

In fact, the contribution of the North Atlantic is so great, without it, the global trend drops by 45%, Figure 6.
http://i56.tinypic.com/2zhei46.jpg
Figure 6

Tamino did not suggest how to account for the global warming signal in his AMO post, unless the last graph in which he subtracts global GISS LAND-Ocean Temperature Index data from North Atlantic SEA Surface Temperature data is his recommendation. But he did make a suggestion on his earlier How Fast is Earth Warming? thread. He wrote in response to a January 23, 2011 at 4:42 pm comment, “It might be interesting to correlate AMO to short-term global temperature fluctuations, if AMO is detrended nonlinearly, or if only the modern era (1975 to present) is detrended separately. But then: the denialists' claim disappears.”

To account for the nonlinear signal, Trenberth and Shea (2006) proposed subtracting the global (60S-60N) SST data from the North Atlantic in “Atlantic hurricanes and natural variability in 2005”. But the North Atlantic represents a major portion (almost 50%) of the recent rise in global SST anomalies (90S-90N) since 1982, Figure 6. Therefore, Trenberth and Shea are suggesting the subtraction of a dataset with a strong North Atlantic signal from the North Atlantic SST data itself. Why not subtract the SST anomalies of the rest of the world from the North Atlantic? It’s the additional variability of the North Atlantic, above and beyond the rest of the world, that’s of interest, not a signal that’s been suppressed by itself.

The reason that method hasn’t been suggested becomes obvious when one compares that dataset to the AMO data based on detrended North Atlantic SST anomalies. Refer to Figure 7. (The “Rest of the World” data is calculated the same as the “Global Without North Atlantic” from Figures 5 & 6.) Note how the curves mimic one another from 1905 to the early 1980s. They diverge from time to time, but the curves are similar. But note how VERY similar the two curves are after 1982. That’s the period of the AMO data used in my “Removing” post.
http://i53.tinypic.com/2v1ukg5.jpg
Figure 7

Let’s look at the satellite-era portion (1982 to present) of those two datasets, Figure 8. The trends are basically the same, and the year-to-year variability of the two signals mimic one another with small divergences and lags. Based on Figure 10, the “Variations in the forced signal do leak into the AMO definition,” as Tamino notes, but they have had little impact on the results of my “Removing” post.
http://i54.tinypic.com/kdpe7c.jpg
Figure 8

THE DIFFERENCE BETWEEN THE KAPLAN AND HADISST NORTH ATLANTIC SST ANOMALIES
The Kaplan and HADISST versions of the North Atlantic SST anomalies were illustrated together in Figure 2. There was a significant difference in their linear trends. For Figure 9, I subtracted the HADISST version of the North Atlantic SST anomalies from the Kaplan SST anomalies used by ESRL (and Tamino for his last graph). Note the similarities between Figure 9 and Tamino’s final graph in his AMO post.
http://i53.tinypic.com/2806uqx.jpg
Figure 9

TAMINO’S FINAL COMPARISONS

Tamino’s post included a comparison graph of Global (90S-90N) GISS LOTI and the North Atlantic SST anomalies he created from the data on the ESRL AMO webpage. The last illustration was a graph of the difference. While I can’t find fault is his not knowing there was a shift in the Kaplan North Atlantic SST data, I can find fault in his using the wrong SST dataset. GISS does not use Kaplan SST.

There is little difference between the HADISST and Reynolds OI.v2 versions of the North Atlantic SST data, as shown in Figure 1. To assure the following comparisons were correct, for the following graphs I spliced those two North Atlantic SST anomaly datasets using the method described by GISS in Step 4 on their current analysis webpage. Had Tamino used the HADISST/Reynolds OI.v2-based GISS SST anomalies for the North Atlantic in his comparison, Figure 10, the difference between it and the Global GISS LOTI data would have maintained the appearance of the AMO.
http://i53.tinypic.com/2hofas0.jpg
Figure 10

And had Tamino detrended both datasets and smoothed them with 121-month filters, Figure 11, he would have noted that the multidecadal variability of the North Atlantic far exceeds that of the Global GISS LOFTI data—even with the additional land surface temperature variability in the LOTI data—even with the exaggeration of polar amplification in the LOTI data—even with the bias caused by GISS’s deletion of polar sea surface temperature data in the LOTI data.
http://i52.tinypic.com/3149sm9.jpg
Figure 11

I’ll respond to his comments about “eyeballing” in another post.

SOURCES
With the exception of the ESRL North Atlantic SST data (linked numerous times in the post), all data are available through the KNMI Climate Explorer:
http://climexp.knmi.nl/selectfield_obs.cgi?someone@somewhere

UPDATE 3-16-11
In this post, one method used to determine the AMO was to calculate it as the difference between the North Atlantic and the Rest of the World SST anomalies. I had used 15% as the scaling factor of the North Atlantic. The 15% was 1/2 of the 30% represented by the surface area of the Atlantic (North and South) when compared to the rest of the world, BUT this excluded the Arctic and Southern Oceans. That is, using the surface areas (Source Wikipedia) of the Atlantic (106.4 million sq. km), Indian (73.5 million sq. km) and Pacific (165.2 million sq. km) Oceans, the Atlantic represents about 30% of the surface area of those ocean basins. Half of that is obviously 15%. Excluding the Arctic and Southern Oceans seemed appropriate for the ballpark number since GISS deletes most of the Southern and Arctic Oceans, and the original post in the series was Can Most Of The Rise In The Satellite-Era Surface Temperatures Be Explained Without Anthropogenic Greenhouse Gases? However, if the Southern and Arctic Oceans are included, the North Atlantic surface area ballpark percentage would drop to around 12%. If you include only the surface area of the coordinates used in the post, that scaling factor for the North Atlantic would drop to around 11.5%.

I will clarify this in another post and illustrate the minimal effect this has on the AMO when the AMO is calculated as the difference between the North Atlantic and Rest of the World SST anomalies.

Ultimately, this has no impact on the conclusion of this post, which was that Tamino had used the wrong SST dataset in his post. To illustrate that fact, I subtracted the Global Land+Ocean Temperature anomalies from the North Atlantic SST anomalies, not the AMO.

Tuesday, February 1, 2011

PRELIMINARY January 2011 SST Anomaly Update

I’ve moved to WordPress.  This post can now be found at PRELIMINARY January 2011 SST Anomaly Update
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Sorry for the delay. Snow (lots of it) and family obligations have kept me from posting and responding to comments on posts for a few days. And yes, I'll be responding to Tamino.

The January 2011 Reynolds OI.v2 Sea Surface Temperature (SST) data through the NOAA NOMADS website won’t be official until February 7th. Refer to the schedule on the NOAA Optimum Interpolation Sea Surface Temperature Analysis Frequently Asked Questions webpage. The following are the preliminary Global and NINO3.4 SST anomalies for January 2011 that the NOMADS website prepares based on incomplete data for the month. I’ve also included the weekly data through January 26, 2011, but I’ve shortened the span of the weekly data, starting it in January 2004, so that the variations can be seen.

PRELIMINARY MONTHLY DATA
Monthly NINO3.4 SST anomalies have taken another drop. Based on the preliminary data they’re at -1.6 deg C.

http://i51.tinypic.com/2rqoadc.jpg
Monthly NINO3.4 SST Anomalies
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Monthly Global SST anomalies, according to the preliminary data, have dropped a healthy 0.04 deg C. The preliminary global SST anomaly is 0.055 deg C.
http://i54.tinypic.com/qqs77l.jpg
Monthly Global SST Anomalies
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A NOTE ABOUT THE YEAR-TO-YEAR VARIABILITY
The following is a repeat of a discussion from the past updates

As noted in the November 2010 SST Anomaly Update, the global SST anomalies do not appear as though they will drop to the level they had reached during the 2007/08 La Niña, even if one were to account for the differences in NINO3.4 SST anomalies. This of course will be raised by alarmists as additional proof of anthropogenic global warming.

But the reason the global SST anomalies have warmed in that time is due primarily to the fact that the East Indian and West Pacific Oceans (about 25% of the surface area of the global oceans) can warm in response to both El Niño and La Niña events. Refer to Can El Niño Events Explain All of the Global Warming Since 1976? – Part 1 and Can El Niño Events Explain All of the Global Warming Since 1976? – Part 2, and the video included in La Niña Is Not The Opposite Of El Niño – The Videos. In addition, the North Atlantic also remains at elevated levels during La Niña events in response to the ENSO-related warming of the Kuroshio-Oyashio Extension. This was discussed and illustrated in the recent post The ENSO-Related Variations In Kuroshio-Oyashio Extension (KOE) SST Anomalies And Their Impact On Northern Hemisphere Temperatures.

Keep in mind, the warm water released from below the surface of the Pacific Warm Pool doesn’t simply vanish at the end of the El Niño.

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WEEKLY DATA
The weekly NINO3.4 SST anomaly data are continuing to cycle up and down at what appears to be the low end of the 2010/11 La Niña. They are at -1.68 deg C.
http://i53.tinypic.com/2edoxo6.jpg
Weekly NINO3.4 SST Anomalies
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Weekly Global SST Anomalies have dropped slightly, and it appears they also might have reached the seasonal low. Will they drop more? They are presently at +0.069 deg C.
http://i55.tinypic.com/jidk6c.jpg
Weekly Global SST Anomalies
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SOURCES
SST anomaly data is available through the NOAA NOMADS website:
http://nomad1.ncep.noaa.gov/cgi-bin/pdisp_sst.sh
or:
http://nomad3.ncep.noaa.gov/cgi-bin/pdisp_sst.sh?lite=

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Comment Policy, SST Posts, and Notes

Comments that are political in nature or that have nothing to do with the post will be deleted.
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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.

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