Searching for a Signal Redux
June 1st, 2009Posted by: Roger Pielke, Jr.
The following comments were first posted on this blog in March, 2006. I am reposting them today in response to an email from a kind fellow who saw my name in the paper and wondered if I had ever “done anything” in this area.
Reactions to Searching for a Signal
Originally published March, 2006
I would love to be the first person to conclusively identify the signal of increasing greenhouse gases in the historical record of disaster losses. I have no doubt that such a study, scientifically solid and peer reviewed, would be widely cited, globally reported, and the author(s) would reach near rock star status in the climate science and advocacy communities. The problem is that I (and a number of colleagues) have been looking for such a signal for more than 10 years, recording our efforts in dozens of papers along the way, and so far the signal hasn’t been found.
On Wednesday this week [March, 2006. The paper that resulted from that talk can be seen here in PDF.] I’ll be giving the NRC Ocean Studies Board’s annual Roger Revelle memorial lecture at the Smithsonian in Washington DC in which I’ll provide an overview of this search and what we’ve found to date. The message of the talk is as follows:
1. Anthropogenic climate change is real.
2. Greenhouse gas reductions make good policy sense.
3. But there is no evidence that energy policies focused on climate change can be an effective tool of disaster mitigation.
4. There is currently no evidence that allows us to attribute to human-caused climate change any part of the decades-long trend of a rising toll of disasters, a record which is dominated by floods and storms.
5. More people are beginning to conduct research in this area and perhaps future research results will tell a different story, but 1-4 above are what can be said today and supported by scientific research.
6. Given the state of the literature, this should not be a controversial conclusion.
7. There are better justifications for GHG reductions than disasters, and there are far better options available to policy makers than energy policies to make a material difference in future impacts of climate and weather extremes.
Of late, as the subject of disasters and climate change has become increasingly salient I have noticed a significant ratcheting up in the intensity of criticism that some leading scientists bring to discussing my work. Some of it, quite frankly, borders on the bizarre. Consider the following recent experiences:
*On several occasions, one in a public forum, a very prominent scientist whose name you would all recognize all but accused me of falsifying my research results in order to hide the global warming signal in disaster losses that he believes must certainly be there. The alternative, that our work is solid, apparently is not a possibility.
*Another prominent scientist whose name you would all recognize quite angrily and nastily accused me in an email of being a climate change denier who refuses to see the truth. I replied with an explanation that I was no denier and I provided a list of a few dozen peer-reviewed papers to support my perspective on climate change and disasters, with no response.
*After giving a lecture at a major U.S. university I had a chance to talk one-on-one with the head of the unit that had invited me (a major unit on campus), who was another big-name-you-would-recognize. His first question for me was to ask my political orientation, stating that it was hard to discern from my talk. I thought it an odd question but I answered him anyway. He had no substantive questions about my talk, so I hope my answer to his political orientation question clarified everything.
*Perhaps most troubling, the editor of a leading scientific journal asked me to “dampen” the message of a peer-reviewed publication for fear that it would be “seized upon” by those seeking to defend their interests in business-as-usual energy policies. I found this incredible – was I really being asked to change scientifically well-supported arguments based on some editorial concerns about politics?!
These sorts of experiences are not completely new for me. In past years I have also described how colleagues have pressured me to be careful about my research because of its supposed political implications for those seeking to justify energy policy action based on reducing disaster impacts. Of course, from where I sit one important message of my research is for advocates of changes in energy policies related to climate change simply to make better arguments and to avoid bad ones. This message would seem to be in everyone’s interests.
Some of the experiences described above can be explained as resulting from interactions with a few hyper-politically-charged scientists, some who are full of anger and vitriol. So perhaps these experiences are only a function of a few bad apples that I have the good fortune to be interacting with. From that perspective perhaps I should not be too concerned by the behavior of these individuals. But given their prominence in the community and its institutions, and the chance that these are not isolated experiences, I do worry that the politicization of climate science is reaching epidemic proportions with profound consequences for the field. From my narrow perspective on the climate science community, viewed through the lens of how my work on disasters is received, it seems that some research is judged not by its content but by how some would like the research to turn out. For my part I will continue searching for a signal of global warming in the disaster record, and if and when I find it you’ll know that I really believe that it is there. And know that I won’t be intimidated, bullied, or pressured into saying otherwise or staying silent.
For those who are interested in my work in this area, the following list of publications focuses primarily on storms and floods and document various ways that we have tried to understand and probe the disaster loss record in these contexts. Of course, there is much research conducted by others on this subject, most of which is referenced in the articles below. We have discussed this subject at length here at Prometheus and new readers can find this discussion under the climate change archives. As in any area of science there is much work in this area remaining to be done, and such research may indeed provide new insights that change the perspectives of today.
PDFs of the articles below, almost all which are peer reviewed, can be found here, and the books should be obtainable from your library. [Papers published since 2005 can be found at the link above.]
Downton, M., J. Z. B. Miller and R. A. Pielke, Jr., 2005. Reanalysis of U.S. National Weather Service Flood Loss Database, Natural Hazards Review, 6:13-22.
Downton, M. and R. A. Pielke, Jr., 2005. How Accurate are Disaster Loss Data? The Case of U.S. Flood Damage, Natural Hazards, Vol. 35, No. 2, pp. 211-228.
Pielke, Jr., R. A., 2005. Are there trends in hurricane destruction? Nature, Vol. 438, December, pp. E11.
Pielke, R. A., 2005. Attribution of Disaster Losses, Science, Vol. 310, December 9, pp. 1615.
Pielke, Jr., R.A., S. Agrawala, L. Bouwer, I. Burton, S. Changnon, M. Glantz, W. Hooke, R. Klein, K. Kunkel, D. Mileti, D. Sarewitz, E. Thompkins, N. Stehr, and H. von Storch, 2005.Clarifying the Attribution of Recent Disaster Losses: A Response to Epstein and McCarthy, Bulletin of American Meteorological Society, Volume 86 (10), pp. 1481-1483.
Pielke, Jr., R. A., C. Landsea, M. Mayfield, J. Laver and R. Pasch, 2005. Hurricanes and global warming, Bulletin of the American Meteorological Society, 86:1571-1575.
Pielke, Jr., R.A. and D. Sarewitz, 2005. Bringing Society back into the Climate Debate, Population and Environment, Volume 26, Number 3, pp. 255-268.
Pielke, Jr., R.A., J. Rubiera, C. Landsea, M. Fernandez, and R.A. Klein, 2003: Hurricane Vulnerability in Latin America and the Caribbean, Natural Hazards Review, 4: 101-114.
Downton, M. and R.A. Pielke, Jr., 2001. Discretion Without Accountability: Politics, Flood Damage, and Climate, Natural Hazards Review, 2(4):157-166.
Downton, M. and R. A. Pielke, Jr., 2001: Politics and disaster declarations. Natural Hazards Observer, 25(4), 1-3.
Changnon, S., R. A. Pielke, Jr., D. Changnon, D., R. T. Sylves, and R. Pulwarty, 2000. Human Factors Explain the Increased Losses from Weather and Climate Extremes, Bulletin of the American Meteorological Society, 81(3), 437-442.
Pielke, Jr., R. A., 2000. Flood Impacts on Society: Damaging Floods as a Framework for Assessment. Chapter 21 in D. Parker (ed.), Floods. Routledge Press: London, 133-155.
Pielke, Jr., R. A. and M.W. Downton, 2000. Precipitation and Damaging Floods: Trends in the United States, 1932-97. Journal of Climate, 13(20),
3625-3637.
Pielke, Jr., R.A., M. Downton, J. Z. B. Miller, S. A. Changnon, K. E. Kunkel, and K. Andsager, 2000: Understanding Damaging Floods in Iowa: Climate and Societal Interactions in the Skunk and Raccoon River Basins, Environmental and Societal Impacts Group, National Center for Atmospheric Research, Boulder, CO, August.
Pielke, Jr., R. A., R.A. Klein and D. Sarewitz, 2000. Turning the Big Knob: Energy Policy as a Means to Reduce Weather Impacts. Energy and Environment, Vol. 11, No. 3, 255-276.
Pielke, Jr., R. A., and R. A. Pielke, Sr. (eds.), 2000: Storms: a volume in the nine-volume series of Natural Hazards & Disasters Major Works published by Routledge Press as a contribution to the International Decade for Natural Disaster Reduction. Routledge Press: London.
Kunkel, K., R. A. Pielke Jr., S. A. Changnon, 1999: Temporal Fluctuations in Weather and Climate Extremes That Cause Economic and Human Health Impacts: A Review. Bulletin of the American Meteorological Society, 80, 6, 1077-1098.
Landsea, C. L., R. A. Pielke, Jr., A. Mestas-Nuez and J. Knaff, 1999. Atlantic Basin Hurricanes: Indicies of Climate Changes. Climate Change, 42, 89-129.
Pielke Jr., R.A., 1999: Nine fallacies of floods. Climatic Change, 42, 413-438.
Pielke, Jr., R. A. and M. Downton, 1999. U.S. Trends in Streamflow and Precipitation: Using Societal Impact Data to Address an Apparent Paradox. Bulletin of the American Meteorological Society, 80(7), 1435-1436.
Pielke, Jr., R.A., and C.W. Landsea, 1999: La Nina, El Nino, and Atlantic Hurricane Damages in the United States. Bulletin of the American Meteorological Society, 80, 10, 2027-2033.
Pielke, Jr., R. A., C. W. Landsea, M. Downton, and R. Muslin, 1999: Evaluation of Catastrophe Models Using a Normalized Historical Record: Why It Is needed and How To Do It. Journal of Insurance Regulation. 18, pp. 177-194.
Pielke, Jr., R. A. and C. W. Landsea, 1998. Normalized Hurricane Damages in the United States: 1925-95. Weather and Forecasting, American Meteorological Society, Vol. 13, 621-631.
Pielke Jr., R. A., 1997: Reframing the U.S. Hurricane Problem. Society and Natural Resources, 10, 485-499.
Pielke, Jr., R. A., and R. A. Pielke, Sr., 1997: Hurricanes: Their Nature and Impacts on Society. John Wiley and Sons Press: London.
June 1st, 2009 at 8:42 pm
“4. There is currently no evidence that allows us to attribute to human-caused climate change any part of the decades-long trend of a rising toll of disasters, a record which is dominated by floods and storms.”
This seems to me a rather strong statement. I have certainly seen many studies that indicate otherwise. Yes, you have studies also. No I haven’t read them. The reason being that in these kinds of disputes, the technicalities are beyond me to evaluate. So I’m not saying you’re right or you’re wrong. I’m saying that the issue seems to me to be in dispute.
Although some AGW activists treat it as resolved and a part of the consensus, I don’t see it as being in that category. All I’m saying is that there is a big difference between listing your extensive published research above and asserting that the signal is not (yet?) visible, and asserting that there is absolutely no evidence for a different point of view.
June 1st, 2009 at 8:54 pm
-1-Dean
I’ve looked and haven’t found or seen any evidence, anyone else who knows different should just show the evidence (and presumably write up an article for Science or Nature!).
June 2nd, 2009 at 9:38 am
Check out, for example, box 14.1 on page 623 (chapter 14) of the IPCC Working Group II report. It describes a number of correlations between climate changes and expanding wildfires. The surrounding text also describes other increases in disaster events (separate from human and cost impacts).
Now admittedly, this doesn’t rise to the level of proving the signal. It is however, a certain level of evidence that moves us toward finding that signal. So are we really just talking about level of burden of proof? You say you haven’t seen _any_ evidence. I found the above in a few minutes, and am sure I could find more such examples, particularly if I had access to a journal library search tool.
Also regarding your #3:
3. But there is no evidence that energy policies focused on climate change can be an effective tool of disaster mitigation.
What level of proof do you think is required to enact public safety policy? Obviously you don’t think we have reached that level yet. But since many public health threats and risks have very long lag times (whether chemical exposures or climate change), we shouldn’t require absolute certainty before enacting policy. Can you put a percentage of certainty that you think should be required (or characterize it some other way)?
PS – I have off-and-on been unable to access comments to Prometheus. The system just hangs. It comes and goes.
June 2nd, 2009 at 9:49 am
PS – This post – http://www.realclimate.org/index.php/archives/2009/02/bushfires-and-climate/#more-654 – on RC, lists a number of papers that indicate a contribution (as opposed to being the “cause”) from climate change to the firestorm in Australia earlier this year.
Again, no claim that this is the missing signal, but it strikes me as initial evidence with which to search for that signal, and seems to contradict your assertion that there is no evidence.
June 2nd, 2009 at 10:01 am
-3-Dean
Thanks. IPCC Table 14.1 deals with wildfire and ecosystem disturbance. It does not deal with loss of life or property damage from extreme events, which is the focus of this post. There is some research that has looked at wildfires in Australia from the standpoint of economic losses, climate change and attribution:
http://sciencepolicy.colorado.edu/prometheus/trends-in-homes-lost-to-autralian-bushfires-4950
As far as what level of certainty is needed to improve adaptation, we crossed that threshold long ago. I’ve been arguing for more attention to adaptation for 15 years.
What I (and others) object to, is the idea that mitigation policies can be an effective tool in reducing disaster losses. There are plenty of good reasons for mitigation policies that do not require making false claims about attribution. Dan Sarewitz and I took this on, among other places, in The New Republic in 2005:
http://sciencepolicy.colorado.edu/admin/publication_files/resource-1694-2005.01.pdf
June 2nd, 2009 at 10:06 am
-4-Dean
I’ll ask about the comments, thanks for the heads up.
With respect to the RC post, it does not change the fact that there is no long-term increase in losses from bushfire in Australia. So whatever the role of climate change may actually be, it has not been so large as to emerge from all of the other factors that lead to bushfire losses. This is not to say that there is no signal, only that whatever signal there may be, cannot be seen in the impacts data. Nonetheless, tehre are plenty of good reasons to improve bushfire policies in Australia, as argued by mcAneney et al. in the link above.
June 2nd, 2009 at 10:31 am
“Thanks. IPCC Table 14.1 deals with wildfire and ecosystem disturbance. It does not deal with loss of life or property damage from extreme events, which is the focus of this post.”
The subject is a climate change connection to disasters. Wildfires can be a disaster.
“With respect to the RC post, it does not change the fact that there is no long-term increase in losses from bushfire in Australia.”
This was not the subject of the post. There are many areas where risk to the public has decreased dramatically in recent years. An impact from climate change does not require that it initially be tied to absolute numerical increases in economic or mortality impact since at first it may just be countering improvements from better science and technology.
It seems to me that you’re debating in circles. Is climate change having an impact on disaster occurance? The proof is not absolute, but there is evidence that it is contributing to disasters (as opposed to causing them). Is that level of evidence adequate such that it helps to justify mitigation policies? That depends on the burden of proof required, which is not a scientific question. For you, the burden of proof has already been met, but not by any climate-disaster connection.
But I still say that it is not accurate to say that there is no evidence tyng climate change to frequency and severity of disasters, including extreme weather events. But I agree that no climate signal has been positively identified yet. The evidence that exists now is part of the process of finding that signal. If and when a paper publishes a claim to finding that signal that stands the test of time, it will build upon the evidence that currently exists.
June 2nd, 2009 at 10:39 am
-7-Dean
“Wildfires can be a disaster”
Yes they can. They certainly were in Australia in February. And yet there is no evidence to support the hypothesis that GHG emissions have led to an increase in wildfire disasters. Here I’ll remind you of what we are talking about, my assertion #4:
“There is currently no evidence that allows us to attribute to human-caused climate change any part of the decades-long trend of a rising toll of disasters, a record which is dominated by floods and storms.”
You dismiss the increasing trend when you write:
“An impact from climate change does not require that it initially be tied to absolute numerical increases in economic or mortality impact . . .”
But it is the specifically documented increase in disaster losses that is the focus of this thread.
We seem to have reached a point where we are debating the semantics of the word “evidence” – we are in agreement when you say:
“I agree that no climate signal has been positively identified yet. he evidence that exists now is part of the process of finding that signal. If and when a paper publishes a claim to finding that signal that stands the test of time, it will build upon the evidence that currently exists.”
Fair enough. We still await that paper