Monthly Archives: September 2010

Is There Agreement Amongst Climate Scientists On The IPCC AR4 WG1? By Brown Et Al 2008

As a follow up to the post

Survey Of Climate Scientists Announced On Hans von Storch’s Weblog “Die Klimazwiebel”

I have posted today on the survey that Fergus Brown, James Annan and I completed two years ago which we reported in

Brown, F., J. Annan, and R.A. Pielke Sr., 2008: Is there agreement amongst climate scientists on the IPCC AR4 WG1?. The summary plot of our data is given below using the following choice of answers:

1. There is no warming; it is a fabrication based on inaccurate/inappropriate measurement. Human activity is not having any significant effect on Climate. The data on which such assumptions are made is so compromised as to be worthless. The physical science basis of AGW theory is founded on a false hypothesis.
2. Any recent warming is most likely natural. Human input of CO2 has very little to do with it. Solar, naturally varying water vapour and similar variables can explain most or all of the climate changes. Projections based on Global Climate Models are unreliable because these are based on too many assumptions and unreliable datasets.
3. There are changes in the atmosphere, including added CO2 from human activities, but significant climate effects are likely to be all within natural limits. The ‘scares’ are exaggerations with a political motive. The undue emphasis on CO2 diverts attention away from other, important research on climate variability and change.
4. There is warming and the human addition of CO2 causes some of it, but the science is too uncertain to be confident about current attributions of the precise role of CO2 with respect to other climate forcings. The IPCC WG1 overestimates the role of CO2 relative to other forcings, including a diverse variety of human climate forcings.
5. The scientific basis for human impacts on climate is well represented by the IPCC WG1 report. The lead scientists know what they are doing. We are warming the planet, with CO2 as the main culprit. At least some of the forecast consequences of this change are based on robust evidence.
6. The IPCC WG1 is compromised by political intervention; I agree with those scientists who say that the IPCC WG1 is underestimating the problem. Action to reduce human emissions of CO2 in order to mitigate against serious consequences is more urgent than the report suggests. This should be done irrespective of other climate and environmental considerations.
7. The IPCC WG1 seriously understates the human influence on climate. I agree with those scientists who say that major mitigation responses are needed immediately to prevent catastrophic serious warming and other impacts projected to result from human emissions of CO2. We are seriously damaging the Earth’s climate, and will continue to face devastating consequences for many years.

Our conclusions were

1. The largest group of respondents (45-50%) concur with the IPCC perspective as given in the 2007 Report.
2. A significant minority (15-20%), however, conclude that the IPCC understated the seriousness of the threat from human additions of CO2.
3. A significant minority (15-20%), in contrast, conclude that the IPCC overstated the role of human additions of CO2 relative to other climate forcings.
4. Almost all respondents (at least 97%) conclude that the human addition of CO2 into the atmosphere is an important component of the climate system and has contributed to some extent in recent observed global average warming.

Our report is discussed further in these posts

Weblogs By My Coauthors Of Our Rejected EOS Forum Article

Of consensus and consistency

Your opinions, please

Our survey is consistent with that reported on Hans von Storch’s weblog in that there is a wider diversity of views on the role of humans within the climate system than is commonly reported. Our survey [which was not permitted to be published in EOS; see] is also another example of the suppression of attempts to  poll the climate science community with respect to their views of natural climate variability and change, and of the role of humans in the climate system than has been communicated by the IPCC.

To my knowledge, no professional organization, such as the American Meteorological Society, the American Geophysical Union, and the European Geosciences Union, as just three examples, have undertaken such surveys of their membership in the preparation of their statements on climate science. This is a very much overdue requirement for the next IPCC assessment.

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2010 Pakistan Floods: Climate Change Or Natural Variability?” by Madhav L Khandekar

I have been alerted to an excellent article by Madhav L. Khandekar from the latest edition of the CMOS Bulletion.  The article is titled

2010 Pakistan Floods: Climate Change Or Natural Variability?”  [this article was also posted on ICECAP]

The article starts with the text

“Among the extreme weather events of summer 2010, the extensive floods in Pakistan and their widespread impacts garnered maximum attention in the media as well as in the scientific community. Several climate scientists expressed concern about such weather extremes becoming more common with future climate change, while the WMO (World Meteorological Organization) issued a statement that theThe extensive weather related cataclysms of July and August ( 2010) fit patterns predicted by climate scientists. Damage due to floods and plight of thousands of people marooned over waterlogged areas were graphically covered in heart-wrenching details by most newspapers and TV news stories in Canada. Per latest estimates, the floods have claimed over 1500 human fatalities so far and over two million more have been rendered homeless. From a personal perspective, the TV footage of women & children in knee-deep water brought back poignant memories of a similar situation I witnessed in Pune, my former home-town (a city 200 km southeast of Mumbai, the largest Indian city on the west coast) in July 1961 when incessant monsoon rains in the first week of July 1961 led to the breaking of a dam resulting in massive flooding of the city, destroying hundreds of homes and drowning dozens of people living along the riverside. Several other cities and regions suffered from similar flooding during the 1961 summer monsoon. As it turned out, the 1961 summer monsoon over India and vicinity was the rainiest monsoon season in the 150-year instrument data which caused extensive flooding and loss of life and property in many regions of the country (India Meteorological Department 1962). This year’s monsoon has been quite vigorous since the third week of July 2010 and heavy rains have caused flooding in the peninsular regions of India and also in the northwest regions bordering with Pakistan. Has the vigorous Indian monsoon of 2010 led to the historic floods in Pakistan? Let us briefly consider the monsoon climatology.”

His conclusion includes the text

“A rapid transition of the ENSO phase from El Niño to La Niña between spring and summer of 2010 appears to be the key element in triggering a vigorous monsoon of 2010 over the Indian subcontinent…….the 2010 Pakistan floods, although seemingly unprecedented, were well within natural variability of monsoonal climate over the Indian subcontinent.”

Read the full article here.

Madhav sent me the e-mail below also when I alerted him that I was posting on his new article

Dear Roger

I look forward to seeing my article on your webblog.

May I suggest, you also want to post my earlier article ” the notoriously unpredictable monsoon” along with the latest one? You did post it a few months ago.

This may enable readers of your blog to realize how Indian ( and possibly south Asian) monsoon which was about 25% below average last summer ( 2009) is about 5% above normal this ( 2010) summer, a dramatic flip from ‘drought’ to ‘flood’ in just one year!

This means that just in one year, the total land-based rains increased by about 30% ( of normal value of about 890 cm). This translates to about 25 cm of rains over the entire land-area of India, about 3.3 million sq km! This represents a huge increase in amount of water falling, from last summer to this summer in four summer months and cannot be fully explained by a simple “global warming & increased atmospheric moisture” hypothesis.

For ready reference, [here is] the PDF of my earlier article which appeared in CMOS Bulletin December 2009.

Regards

Madhav

Khandekar, M., 2009: The Notoriously Unpredictable Monsoon, CMOS Bulletin SCMO Vol.37, No.6

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Report On Sea Level Rise And Ground Water Extraction

There is a news article from the University of Utrecht [thanks to Erik for alerting us to this!] titled

Rising sea levels attributed to global groundwater extraction

The article starts with the text

“Large-scale groundwater extraction for irrigation, drinking water or industry results in an annual rise in sea levels of approximately 0.8 mm, accounting for about one-quarter of total annual sea-level rise (3.1 mm). According to hydrologists from Utrecht University and the research institute Deltares, the rise in sea levels can be attributed to the fact that most of the groundwater extracted ultimately winds up in the sea. The hydrologists explain their findings in an article to be published in the near future in the journal Geophysical Research Letters.”

The article is based on the paper

Y. Wada, L.P.H. van Beek, C.M. van Kempen, J.W.T.M. Reckman, S. Vasak, and M.F.P. Bierkens (2010), Global depletion of groundwater resources, Geophysical Research Letters, doi:10.1029/2010GL044571, in press.

This is yet another paper that shows the interconnection among the components of the climate system. The attribution of a climate effect (in this case sea level rise) to just one cause (e.g. ocean warming and glacial melt due to positive radiative forcing from anthropogenic greenhouse gases) is too narrow of a perspective.

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Comments On NOAA’s Report Of Deep Ocean Warming

I was alerted by Leonard Ornstein to a NOAA news article titled

Scientists Find 20 Years of Deep Water Warming Leading to Sea Level Rise

The article includes the text

“Scientists analyzing measurements taken in the deep ocean around the globe over the past two decades find a warming trend that contributes to sea level rise, especially around Antarctica.

Greenhouse gases in the atmosphere, such as carbon dioxide, cause heating of the Earth. Over the past few decades, at least 80 percent of this heat energy has gone into the ocean, warming it in the process.

“Previous studies have shown that the upper ocean is warming, but our analysis determines how much additional heat the deep ocean is storing from warming observed all the way to the ocean floor,” said Sarah Purkey, an oceanographer at the University of Washington and lead author of the study.

This study shows that the deep ocean – below about 3,300 feet – is taking up about 16 percent of what the upper ocean is absorbing. The authors note that there are several possible causes for this deep warming: a shift in Southern Ocean winds, a change in the density of what is called Antarctic Bottom Water, or how quickly that bottom water is formed near the Antarctic, where it sinks to fill the deepest, coldest portions of the ocean around much of the globe.

The scientists found the strongest deep warming around Antarctica, weakening with distance from its source as it spreads around the globe….”

I wrote in the paper

Pielke Sr., R.A., 2003: Heat storage within the Earth system. Bull. Amer. Meteor. Soc., 84, 331-335.

“An assessment of the heat storage within the earth’s climate system offers a unique perspective on global change. If the heat actually remains within the earth system in the deeper ocean, for example, while the heat content of the remainder of the heat reservoirs in the earth system remains unchanged, sudden transfers of the heat between components of the system (from the ocean into the atmosphere) could produce rapid, unanticipated changes in global weather. “

Since I wrote that statement, I have become convinced that since deep ocean heating is diffused through relatively large volumes of the ocean (as indicated in the NOAA study), it cannot suddenly reappear in the atmosphere.  Indeed, we can now monitor with the Argo network in order to assess if there are large amounts of heat (in Joules) migrating towards the surface of the ocean.

There are several  comments and questions that result from this study:

  1. First, since the warming is concentrated in the higher southern latitudes, how did was this heat transferred through the upper ocean without being sampled by the Argo network or in the satellite measurements of ocean surface temperatures?
  2. If a significant fraction of the radiative forcing is transferred deep into the ocean, it is effectively “sequestered” and is not easily available to affect atmospheric climate.
  3. The heating of the deeper ocean does assist in part with explaining sea level rise in the absence of upper ocean heating.
  4. The fraction of heating that is within the deeper ocean reduces the magnitude of heat available to increase the global average surface temperature.

Since the data density of this study was relatively coarse, however, further study is needed to confirm their values. Nonetheless, this is the type of diagnosis we need, along with the Argo network, to obtain a more accurate diagnosis of global warming and cooling.

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Filed under Climate Change Metrics, Climate Science Reporting

Invited Letter Now Rejected By Nature Magazine

UPDATE: September 27 2010 – see the post  “You Are Invited To Waste Your Time”

I was invited by Nature magazine to write a Letter in response to the September Exeter meeting http://www.surfacetemperatures.org/home, and have been working with a member of their staff on edits over the past two weeks.

This morning, I received the startling e-mail below from Nature’s Chief Commissioning Editor. Quite frankly, the only way I can interpret this behavior is as an example of the continued bias in Nature’s reporting of climate issues. Their statement that “We have now reflected on the matter, and on some information from attendees at the meeting in question”  is a remarkable admission.

Dear Professor Pielke,
 
Thank you very much for taking the time to write to Nature, upon request. And for the revisions you’ve made, again at our request.
 
We have now reflected on the matter, and on some information from attendees at the meeting in question. We have, I’m afraid concluded that we cannot offer publication on this occasion. We feel that there are too many nuances to this situation to be properly communicated by a short item (or items) on our letters page.
 
We will however continue to track the evolving story for news or leaders, as appropriate.
 
We apologise for having taken up your time in this way.
 
Sincerely,
 
Sara Abdulla
Chief Commissioning Editor
Opinion [incl Correspondence and Books & Arts]
Nature

Temperature dataset effort vulnerable to problems

by Roger A. Pielke Sr.
 
Peter Stott and Peter Thorne recently conducted a meeting in Exeter to improve the quality control and archival procedures for global surface temperature data, at which I was not present. I applaud the aim of this meeting (doi:10.1038/4661040d) — to solicit multiple views from the climate community on how to create confidence in raw data and metadata, and to provide a set of blind benchmarking tools for the assessment of data adjustment algorithms. But I worry that the group seemingly has yet to tackle some valid concerns about that data.
 
I was glad to see in the meeting notes several candid admissions of the shortcomings of existing surface temperature data assessments. The group acknowledged the problem of undocumented changes to temperature records and a lack of international exchange of detailed stations histories,  as well as the recognition that non-traditional climate scientists are now playing a significant role in constructing a better climate dataset. They recognized that there may be important, unresolved systematic biases and uncertainties in the current data, and acknowledged the value of efforts such as www.surfacestations.org, which has prodded the US National Climatic Data Center and others to examine their analyses more rigorously. The group’s commitment to quantifying and reporting statistical uncertainties and data adjustments is to be commended.
 
But the meeting notes suggest that the group did not sufficiently address other valid concerns about data collection [Pielke et al 2007]. These include the need to  improve the improve the documentation of humidity at temperature stations [e.g. Davey et al 2006; Fall et al 2010],  the height of the observations [Klotzbach et al 2009, Lin et al 2007] and to pay more attention to the siting of surface stations. Many stations still have not been documented with photographs, for example – this is a simple problem that should be addressed immediately.  
 
I would like to see the Exeter group address these issues explicitly, and, importantly, make a commitment to having all analyses and findings from these data sets assessed by independent scientists [Mahmood et al 2010]. All too often in the past, results have been assessed by scientists associated with the agencies that performed the analyses. This should not continue.
 
References
 
Pielke Sr., R.A., C. Davey, D. Niyogi, S. Fall, J. Steinweg-Woods, K. Hubbard, X. Lin, M. Cai, Y.-K. Lim, H. Li, J. Nielsen-Gammon, K. Gallo, R. Hale, R. Mahmood, S. Foster, R.T. McNider, and P. Blanken, 2007: Unresolved issues with the assessment of multi-decadal global land surface temperature trends. J. Geophys. Res., 112, D24S08, doi:10.1029/2006JD008229.
 
Davey, C.A., R.A. Pielke Sr., and K.P. Gallo, 2006: Differences between near-surface equivalent temperature and temperature trends for the eastern United States – Equivalent temperature as an alternative measure of heat content. Global and Planetary Change, 54, 19–32.
 
Fall, S., N. Diffenbaugh, D. Niyogi, R.A. Pielke Sr., and G. Rochon, 2010: Temperature and equivalent temperature over the United States (1979 – 2005). Int. J. Climatol., DOI: 10.1002/joc.2094.

Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2009: An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., 114, D21102, doi:10.1029/2009JD011841.
 
Lin, X., R.A. Pielke Sr., K.G. Hubbard, K.C. Crawford, M. A. Shafer, and T. Matsui, 2007: An examination of 1997-2007 surface layer temperature trends at two heights in Oklahoma. Geophys. Res. Letts., 34, L24705, doi:10.1029/2007GL031652.
 
Mahmood, R., R.A. Pielke Sr., K.G. Hubbard, D. Niyogi, G. Bonan, P. Lawrence, B. Baker, R. McNider, C. McAlpine, A. Etter, S. Gameda, B. Qian, A. Carleton, A. Beltran-Przekurat, T. Chase, A.I. Quintanar, J.O. Adegoke, S. Vezhapparambu, G. Conner, S. Asefi, E. Sertel, D.R. Legates, Y. Wu, R. Hale, O.W. Frauenfeld, A. Watts, M. Shepherd, C. Mitra, V.G. Anantharaj, S. Fall,R. Lund, A. Nordfelt, P. Blanken, J. Du, H.-I. Chang, R. Leeper, U.S. Nair, S. Dobler, R. Deo, and J. Syktus, 2010: Impacts of land use land cover change on climate and future research priorities. Bull. Amer. Meteor. Soc., 91, 37–46, DOI: 10.1175/2009BAMS2769.1

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Weather And Climate – Well Summarized By On Tomas Milanovic On Climate Etc.

Tomas Milanovic has a accurate succinct summary of the relationship between weather and climate on the weblog post The Uncertainty Monster at Climate Etc.

The comment reads

“Weather is chaotic, nobody disputes that. The “climate” is exactly the same system, obeying to the same laws and described by the same equations like weather. The only difference being that the variables of the system “climate” are space and time averages instead of the instantaneous values. In addition for practical purposes the weather time scale is defined in days so that many slow variables are considered constant what spares computing time. However it is clear that if the system is chaotic with these constant coefficients , it will be chaotic with variable coefficients on longer time scales too.”

The issue of what is climate is discussed further in the article

Pielke, R.A., 1998: Climate prediction as an initial value problem. Bull. Amer. Meteor. Soc., 79, 2743-2746

where I wrote

“….weather prediction is a subset of climate prediction. Societally useful (i.e. reliable, accurate,etc.) requires that all of the feedbacks and other physical processes included in weather prediction be represented in the climate prediction model. In addition, longer-term feedback and physical processes must be included. This makes climate prediction a much more difficult problem than weather prediction.”

Indeed, climate models must not only be able to simulate weather features such as high and low pressure systems including tropical cyclones are well as operational numerical weather prediction models, but must be able to accurately simulate a diverse variety of physical, chemical and biological processes. Even then, nonlinear interactions between the many components of the climate system (e.g. as illustrated in Figure 1 in Rial et al 2004) can result in limiting skillful prediction decades into the future.  The Milanovic comment on Climate Etc. effectively summarizes this issue. A subject that is not properly assessed in the 2007 IPCC report.

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Survey Of Climate Scientists Announced On Hans von Storch’s Weblog “Die Klimazwiebel”

A detailed survey of climate scientists has just been announced by Hans von Storch on his website Die Klimazwiebel in a post titled

CliSci Survey – results documented

The report, by Dennis Bray and Hans von Storch is titled

GKSS-Report 2010/9: CliSci2008: A Survey of the Perspectives of Climate Scientists Concerning Climate Science and Climate Change.

There is quite a lot of  useful survey information and I will comment on some of the results in a later post.

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New Paper “On Potential Causes For An Under-Estimated Global Ocean Heat Content Trend In CMIP3 Models” By Cai Et Al 2010

There is a new paper on the comparison of model and observed global ocean heat content changes for the period 1951 to 1999 (thanks to Josh Willis for alerting us to it!). The paper is

Cai, W., T. Cowan, J. M. Arblaster, and S. Wijffels (2010), On potential causes for an under-estimated global ocean heat content trend in CMIP3 models, Geophys. Res. Lett., 37, L17709, doi:10.1029/2010GL044399.

“Trends in global oceanic heat content (OHC) over the late 20th century as simulated by climate models that incorporate all radiative forcing factors are smaller than the observed, but the causes are not clear. Given the cooling effect associated with increasing anthropogenic aerosols and natural forcing (i.e., volcanic aerosols), we examine their respective roles in the simulated global OHC trend and the associated ocean temperature structure, using targeted experiments from two models, designed to separate the individual impacts of these forcing components. We show that it is more likely that the indirect effect of aerosols, not volcanic aerosols alone, is the reason for the bulk of weaker  modelled OHC trends. Further, anthropogenic aerosols are essential for simulating the structure of the observed temperature changes, including a concentrated cooling in the Southern Hemisphere subtropical latitudes, consistent with a more stable global Conveyer, a greater strengthening of the subtropical gyre circulation, and a stronger Southern Annular Mode trend in targeted experiments with anthropogenic aerosol forcing.”

The introduction starts with the text

“An ensemble mean of 20th century model experiments (submitted as part of the Coupled Model Intercomparison Project Phase 3 (CMIP3)) forced with all forcing factors
(ALL) such as time‐varying well‐mixed greenhouse gases, anthropogenic and volcanic aerosols, ozone depletion, and solar irradiance, produces a linear trend in the upper 300m OHC over 1961–1999 that is 28% smaller than the observed [Domingues et al., 2008].”

An excerpt from the conclusion reads

“A subgroup of CMIP3 20th century experiments with all forcing factors produces a global OHC trend since 1951– 1999 that is too weak when compared with the observed,
whereas another subgroup without natural forcings overestimates the global OHC trend.”

This study is the type we need to test the IPCC model projections. This study, of course, is for the period 1951 to 1999. There is a need to include the last 11 years in this assessment, since the last few years have seen little, if any warming, as diagnosed by the upper ocean heat content changes; i.e. see

R. S. Knox, David H. Douglass 2010: Recent energy balance of Earth  International Journal of Geosciences, 2010, vol. 1, no. 3 (November) – In press doi:10.4236/ijg2010.00000.

In addition,  the Cai et al 2010 paper is not only puzzling because it examined only up through 1999, they also could only look at modeled natural variability, not the real world variability, the later of which is clearly larger than the models have so far been able to replicate. Moreover, despite their claim that the “Coupled Model Intercomparison Project Phase 3 (CMIP3)) [is] forced with all forcing factors“, it is not, as we document in the 2005 NRC report

National Research Council, 2005: Radiative forcing of climate change: Expanding the concept and addressing uncertainties. Committee on Radiative Forcing Effects on Climate Change, Climate Research Committee, Board on Atmospheric Sciences and Climate, Division on Earth and Life Studies, The National Academies Press, Washington, D.C., 208 pp.
http://www.nap.edu/openbook/0309095069/html/

An update of the Cai et al  study to 2010 would be of considerable value, as well as the identification of what climate forcings and feedbacks are incompletely modelled and/or are left out of the models.

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Filed under Climate Change Metrics, Research Papers

Comment To Andy Revkin On The Dot Earth Post “A-Sharp-Ocean-Chill-And-20th-Century-Climate”

Dot Earth has a post titled A Sharp Ocean Chill and 20th Century Climate

David W. J. Thompson, John M.Wallace, John J. Kennedy & Phil D. Jones, 2010: An abrupt drop in Northern Hemisphere sea surface temperature around 1970. Nature. doi:10.1038/nature09394

The abstract reads

“The twentieth-century trend in global-mean surface temperature was not monotonic: temperatures rose from the start of the century to the 1940s, fell slightly during the middle part of the century, and rose rapidly from the mid-1970s onwards. The warming– cooling–warming pattern of twentieth-century temperatures is typically interpreted as the superposition of long-term warming due to increasing greenhouse gases and either cooling due to a mid-twentieth century increase of sulphate aerosols in the troposphere, or changes in the climate of the world’s oceans that evolve over decades (oscillatory multidecadal variability). Loadings of sulphate aerosol in the troposphere are thought to have had a particularly important role in the differences in temperature trends between the Northern and Southern hemispheres during the decades following the Second World War2–4. Here we show that the hemispheric differences in temperature trends in the middle of the twentieth century stem largely from a rapid drop in Northern Hemisphere sea surface temperatures of about 0.3 C between about 1968 and 1972. The timescale of the drop is shorter than that associated with either tropospheric aerosol loadings or previous characterizations of oscillatory multidecadal variability. The drop is evident in all available historical sea surface temperature data sets, is not traceable to changes in the attendant metadata, and is not linked to any known biases in surface temperature measurements. The drop is not concentrated in any discrete region of the Northern Hemisphere oceans, but its amplitude is largest over the northern North Atlantic.”

In response to Andy’s alerting me to this post, I replied 

Hi Andy

 This is a very good Dot Earth post. The Thompson et al paper is an example of what we discussed in our paper

Rial, J., R.A. Pielke Sr., M. Beniston, M. Claussen, J. Canadell, P. Cox, H. Held, N. de Noblet-Ducoudre, R. Prinn, J. Reynolds, and J.D. Salas, 2004: Nonlinearities, feedbacks and critical thresholds within the Earth’s climate system. Climatic Change, 65, 11-38.
http://pielkeclimatesci.files.wordpress.com/2009/10/r-260.pdf.

As we wrote in the abstract

“The Earth’s climate system is highly nonlinear: inputs and outputs are not proportional, change is often episodic and abrupt, rather than slow and gradual, and multiple equilibria are the norm. While this is widely accepted, there is a relatively poor understanding of the different types of nonlinearities, how they manifest under various conditions, and whether they reflect a climate system driven by astronomical forcings, by internal feedbacks, or by a combination of both.”

We present examples of this nonlinear behavior across a variety of space and time scales in our paper.

Among our conclusions is that we recommend to

“[i]mprove our vision of the climate’s future through a better understanding of its history. Paleoclimate and hydroclimate records exhibit abrupt changes in the form of rapid warming events, the irregular oscillations of ENSO, catastrophic floods, sustained droughts, and many other nonlinear response characteristics. Extracting, identifying, categorizing, modeling and understanding these nonlinearities will greatly help our ability to understand the present and future state of the climate”

and

“Understand the global connectivity and variability of ocean-atmosphere coupled phenomena, such as the North Pacific Oscillation (NPO), the Pacific Decadal Oscillation (PDO), the Arctic Oscillation (AO), the North Atlantic Oscillation (NAO), and the El Niño/Southern Oscillation (ENSO).”

In the comments on Dot Earth, I note that there remains an impression that models can be used to explain the observations. However, models are only hypotheses which must be tested in terms of their skill at prediction. It is clear that the multi-decadal global models remain unable to skillfully simulate regional ocean/atmospheric features such as exemplified in the Thompson et al paper.

I also agree with the comments of Carl Wunsch that there is a limited selection of papers that are highlighted. We need a way to be more inclusive and your weblog is serving as an excellent venue for this purpose.

Best Regards

Roger Sr.

P.S. My comment above can be posted if you chose to.

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Filed under Climate Change Forcings & Feedbacks, Climate Science Reporting

Further Confirmation Of Klotzbach Et al 2009

In

Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2009: An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., 114, D21102, doi:10.1029/2009JD011841.

Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2010: Correction to: “An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., 114, D21102, doi:10.1029/2009JD011841″, J. Geophys. Res., 115, D1, doi:10.1029/2009JD013655

we concluded

“This paper investigates surface and satellite temperature trends over the period from 1979 to 2008. Surface temperature data sets from the National Climate Data Center and the Hadley Center show larger trends over the 30-year period than the lower-tropospheric data from the University of Alabama in Huntsville and Remote Sensing Systems data sets. The differences between trends observed in the surface and lower-tropospheric satellite data sets are statistically significant in most comparisons, with much greater differences over land areas than over ocean areas. These findings strongly suggest that there remain important inconsistencies between surface and satellite records.”

In our paper,

Christy, J.R., Herman, B., Pielke, R., Sr., Klotzbach, P., McNider, R.T., Hnilo, J.J., Spencer, R.W., Chase, T., and Douglass, D. What Do Observational Datasets Say about Modeled Tropospheric Temperature Trends since 1979?. Remote Sens. 2010, 2, 2148-2169.

in which this issue was explored further we reported that

“However, at this time, the evidence implies that in the satellite era, the relationship between the surface and tropospheric trends in the tropics is significantly different between observations and models. This result is consistent with that of [7,8] who compared global surface and tropospheric trends between observations and models and found significant differences over composites of both land and ocean.”  [references 7 and 8 are Klotzbach et al 2009 and 2010].

An ideal candidate for explaining this divergence between the lower tropospheric and surface temperature records is a systematic warm bias in the surface temperature trend data. As presented yesterday (see), even the research groups who are using this data to admit to a lack of information on the siting history of these surface (GHCN) observing locations.

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