I’ve moved to WordPress. This post can now be found at Multiple Wrongs Don’t Make A Right, Especially When It Comes To Determining The Impacts Of ENSO
############The 2009 Foster et al paper (In Press) “Comment on ‘Influence of the Southern Oscillation on tropospheric temperature’ by J. D. McLean, C. R. de Freitas, and R. M. Carter” was written by a who’s who of climate scientists. The authors include G. Foster, J. D. Annan, P. D. Jones, M. E. Mann, B. Mullan, J. Renwick, J. Salinger, G. A. Schmidt, and K. E. Trenberth. Their comment is summarized by a sentence in the abstract: “Their [McLean, Freitas, and Carter’s] analysis is incorrect in a number of ways, and greatly overstates the influence of ENSO on the climate system.”
Link to Preprint (The Google link to the pdf version of the preprint is no longer operational):
http://74.125.47.132/search?q=cache:0hqurMRrw2UJ:www.cgd.ucar.edu/cas/Trenberth/trenberth.papers/FosteretalJGR09.pdf+Comment+on+%E2%80%9CInfluence+of+the+Southern+Oscillation+on+tropospheric+temperature%E2%80%9D+by+J.+D.+McLean,+C.+R.+de+Freitas,+and+R.+M.+Carter+(Foster+et+al+2009)&cd=1&hl=en&ct=clnk&gl=us
This post does not discuss the analysis by Carter et al nor does it examine the methods used by Foster et al to critique it. This post lists the papers cited by Foster et al that determine “the connection between ENSO and large-scale temperature variability, particularly with regard to the role of ENSO in any long-term warming trends, that has been carried out over the past two decades,” and discusses the errors that are common to those papers.
THE PAPERS CITED BY FOSTER ET AL
Jones, P.D., (1989), The influence of ENSO on global temperatures, Climate Monitor, 17, 80–89.
(I have not found a link to this paper. Since I haven’t read it, I can’t comment about it. It is, therefore, excluded from my post.)
Santer, B.D., Wigley, T.M.L., Doutriaux, C., Boyle, J.S., Hansen, J.E., Jones, P.D., Meehl, G.A., Roeckner, E., Sengupta, S., and Taylor K.E. (2001), Accounting for the effects of volcanoes and ENSO in comparisons of modeled and observed temperature trends, J. Geophys. Res., 106, 28033–28059.
Link:
http://pubs.giss.nasa.gov/docs/2001/2001_Santer_etal.pdf
Thompson, D. W. J., J. J. Kennedy, J. M. Wallace, and P. D. Jones (2008), A large discontinuity in the mid-twentieth century in observed global-mean surface temperature, Nature, 453, 646–650, doi:10.1038/nature06982.
http://www.nature.com/nature/journal/v453/n7195/abs/nature06982.html
Trenberth, K.E., J.M.Caron, D.P.Stepaniak, and S.Worley, (2002), Evolution of El Nino-Southern Oscillation and global atmospheric surface temperatures, J. Geophys. Res., 107 (D8), 4065, doi:10.1029/2000JD000298
http://www.cgd.ucar.edu/cas/papers/2000JD000298.pdf
Wigley, T. M. L. (2000), ENSO, volcanoes, and record-breaking temperatures, Geophysical Res. Lett., 27, 4101–4104.ENSO, volcanoes and record‐breaking temperatures
http://www.agu.org/pubs/crossref/2000/2000GL012159.shtml
COMMON ERRORS IN PAPERS CITED BY FOSTER ET AL
The authors of the papers used different statistical tools and ENSO indices to remove the ENSO signal from Global Temperature and TLT records, and they all failed to account for the multiyear aftereffects of significant El Nino events. This was discussed in detail in my post “Regression Analyses Do Not Capture The Multiyear Aftereffects Of Significant El Nino Events”. That post also appeared at WattsUpWithThat as “Why regression analysis fails to capture the aftereffects of El Nino events.” The post included a detailed discussion of the processes that take place before, during, and after significant El Nino events under the heading “EL NINO OVERVIEW”.
That overview was supplemented by my post “La Nina Events Are Not The Opposite Of El Nino Events.” Briefly, a La Nina event is an exaggeration of ENSO-neutral conditions that occurs when the coupled ocean-atmosphere processes attempt to return to “normal” after a traditional El Nino.
The statistical techniques used in the papers cited by Foster et al also do not address the differences between traditional El Nino events and El Nino Modoki. El Nino Modoki events were discussed in my posts “There Is Nothing New About The El Nino Modoki” and “Comparison of El Nino Modoki Index and NINO3.4 SST Anomalies.”
And the papers that Foster et al cite do not account for “The Reemergence Mechanism,” which should integrate the effects of ENSO events.
ALSO IN PREPRINT RELEASE: THOMPSON ET AL (2009) REPEATS THE ERROR
The 2009 Thompson et al paper “Identifying signatures of natural climate variability in time series of global-mean surface temperature: Methodology and Insights” has been accepted for publication by the Journal of Climate. In it, Thompson et al repeat the errors made by Thompson et al 2008.
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F2009JCLI3089.1
Preprint Version:
http://www.atmos.colostate.edu/ao/ThompsonPapers/TWJK_JClimate2009_revised.pdf
Thompson et al were kind enough to post the data that resulted from their analyses for those who like to review findings:
http://www.atmos.colostate.edu/~davet/ThompsonWallaceJonesKennedy/
CLOSING
As long as climate scientists continue to neglect the multiyear aftereffects of significant El Nino events, they will continue to incorrectly conclude, as Foster et al concludes, “the general rise in temperatures over the 2nd half of the 20th century is very likely predominantly due to anthropogenic emissions of greenhouse gases.”
3 comments:
par5: You wrote, “So, a ‘la nina’ event will not take us from neutral to cool because it can only take us from warm to neutral?”
Not even close to a rewording of what I wrote. My sentence about La Ninas in the post , “a La Nina event is an exaggeration of ENSO-neutral conditions that occurs when the coupled ocean-atmosphere processes attempt to return to ‘normal’ after a traditional El Nino,” pertained to trade winds, currents, etc., in the tropical Pacific, not the impact of a La Nina on global temperature. It is explained in detail in the linked post. Here’s the link again:
http://bobtisdale.blogspot.com/2009/08/la-nina-events-are-not-opposite-of-el.html
Regards
Hi Bob- sorry I screwed up my question. I was not speaking of global temps but the conditions of the event. I got into a lengthy debate two days ago about heat dissipation in the oceans. If energy travels from hot to cold, which way does the heat energy go from the sea surface? Both ways, right? Since gravity has nothing to do with heat rising, we thought that the majority of heat would travel toward the lowest temp- which is down, not up. We could not agree on the percentage, however. Why wouldn't the currents drive more heat downwards?
par5: You wrote, “So, a ‘la nina’ event will not take us from neutral to cool because it can only take us from warm to neutral?”
Not even close to a rewording of what I wrote. My sentence about La Ninas in the post , “a La Nina event is an exaggeration of ENSO-neutral conditions that occurs when the coupled ocean-atmosphere processes attempt to return to ‘normal’ after a traditional El Nino,” pertained to trade winds, currents, etc., in the tropical Pacific, not the impact of a La Nina on global temperature. It is explained in detail in the linked post. Here’s the link again:
http://bobtisdale.blogspot.com/2009/08/la-nina-events-are-not-opposite-of-el.html
Regards
Hi Bob, sorry I screwed up my question. I was not speaking of global temps, just the conditions of the events. I was in a rather lengthy discussion the other day about heat energy dissipation in the oceans. Since energy always travels from hot to cold, we finally agreed that sea surface heat travels in both directions, up and down. Because the sea is colder than the atmosphere above, we decided to accept that a majority of this heat travels downwards. Do stronger trade winds pull more heat up and out? Do currents drive more heat up or down?
par5: Your questions here appear to be rewordings of the questions you asked over on the "La Nina Events Are Not The Opposite of El Nino Events" thread. I'll repeat the answers here.
Regarding tropical Pacific trade winds during La Nina events, the trade winds are higher than normal during ENSO-neutral conditions. They pick up more heat and moisture as they travel west, which would cool the ocean surface more than normal. But the increase in trade winds also decrease cloud amounts in the eastern tropical Pacific, don’t they? This would increase downwelling shortwave radiation and increase the OHC. Pavlakis et al found that DSR was the greatest contributor to net heat flux into ocean and that total cloud amount over the tropical Pacific dictated DSR.
http://www.atmos-chem-phys-discuss.net/8/6697/2008/acpd-8-6697-2008-print.pdf
The following is from my post “Recharging the Pacific Warm Pool Part 2”
http://bobtisdale.blogspot.com/2009/02/recharging-pacific-warm-pool-part-2.html
Pavlakis et al state, “The net heat flux into the ocean is a small residual of four terms; the net shortwave radiation at the surface (NSR), the latent heat loss, the sensible heat transfer and the net downwelling longwave radiation at the Earth’s surface (NSL). The NSL is the difference between the downward longwave radiation (DLR) at the Earth’s surface and the Earth’s surface thermal emission.”
They continue, “The NSR is the difference between the downwelling shortwave radiation (DSR) and the reflected radiation from the ocean surface. However, the reflected term is more than one order of magnitude smaller than the DSR, since the ocean albedo is less than 0.07. Thus, DSR dominates the net shortwave flux budget. The variability of DSR, the component of the net heat into the ocean with the largest magnitude, reflects mostly fluctuations in cloud cover caused by variations in atmospheric circulation and thus, it is very important in order to describe and study the intensity or duration of ENSO events.”
Regarding your question about currents, I haven’t studied all of the subsurface currents (and there are many) in tropical Pacific to answer this. But if they’re causing warmer- or cooler-than-normal water to be subducted in one location, water is rising in another.
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