Judith Curry: Climate change can be categorized as a “wicked problem.”, praises blogosphere and cites a need for acknowledgement

Curry – Testimony on Rational Discussion of Climate Change

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STATEMENT TO THE

SUBCOMMITTEE ON ENERGY AND ENVIRONMENT

OF THE UNITED STATES HOUSE OF REPRESENTATIVES

Hearing on

“Rational Discussion of Climate Change: the Science, the Evidence, the Response”

17 November 2010

Judith A. Curry

Georgia Institute of Technology

curryja@eas.gatech.edu

I thank the Chairman and the Committee for the opportunity to offer testimony today on “Rational

Discussion of Climate Change.” I am Chair of the School of Earth and Atmospheric Sciences at the

Georgia Institute of Technology. As a climate scientist, I have devoted 30 years to conducting research

on a variety of topics including climate feedback processes in the Arctic, energy exchange between the

ocean and the atmosphere, the role of clouds and aerosols in the climate system, and the impact of

climate change on the characteristics of hurricanes. As president of Climate Forecast Applications

Network LLC, I have been working with decision makers on climate impact assessments, assessing

and developing climate adaptation strategies, and developing subseasonal climate forecasting

strategies to support adaptive management and tactical adaptation. Over the past year, I have been

actively engaging with the public (particularly in the blogosphere) on the issue of integrity of climate

science, and also the topic of uncertainty.

The climate change response challenge

Climate change can be categorized as a “wicked problem.”1 Wicked problems are difficult or

impossible to solve, there is no opportunity to devise an overall solution by trial and error, and there

is no real test of the efficacy of a solution to the wicked problem. Efforts to solve the wicked problem

may reveal or create other problems.

The United Nations Framework Convention on Climate Change (UNFCCC) and the Intergovernmental

Panel on Climate Change (IPCC) have framed the climate change problem (i.e. dangers) and its

solution (i.e. international treaty) to be irreducibly global. Based upon the precautionary principle, the

UNFCCC ’s Kyoto Protocol has established an international goal of stabilization of the concentrations

of greenhouse gasses in the atmosphere. This framing of the problem and its solution has led to the

dilemma of climate response policy that is aptly described by Obersteiner et al.2:

The key issue is whether “betting big today” with a comprehensive global climate policy

targeted at stabilization “will fundamentally reshape our common future on a global scale to

our advantage or quickly produce losses that can throw mankind into economic, social, and

environmental bankruptcy.”

1 Rittel, Horst, and Melvin Webber; “Dilemmas in a General Theory of Planning,” pp. 155–169, Policy

Sciences, Vol. 4, Elsevier Scientific Publishing Company, Inc., Amsterdam, 1973.

Click to access Rittel+Webber+Dilemmas+General_Theory_of_Planning.pdf

2 http://helda.helsinki.fi/bitstream/handle/1975/292/2001-Managing_climate_risk.pdf?sequence=1

Curry – Testimony on Rational Discussion of Climate Change

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In a rational discussion of climate change, the question needs to be asked as to whether the framing of

the problem and the early articulation of a preferred policy option by the UNFCCC has marginalized

research on broader issues surrounding climate change, and resulted is an overconfident assessment of

the importance of greenhouse gases in future climate change, and stifled the development of a broader

range of policy options.

The IPCC/UNFCCC have provided an important service to global society by alerting us to a global

threat that is potentially catastrophic. The UNFCCC/IPCC has made an ambitious attempt to put a

simplified frame around the problem of climate change and its solution in terms of anthropogenic

forcing and CO2 stabilization polices. However, the result of this simplified framing of a wicked

problem is that we lack the kinds of information to more broadly understand climate change and

societal vulnerability.

Uncertainty in climate science

Anthropogenic climate change is a theory in which the basic mechanism is well understood, but in

which the magnitude of the climate change is highly uncertain owing to feedback processes. We know

that the climate changes naturally on decadal to century time scales, but we do not have explanations

for a number of observed historical and paleo climate variations, including the warming from 1910-

1940 and the mid-20th century cooling. The conflict regarding the theory of anthropogenic climate

change is over the level of our ignorance regarding what is unknown about natural climate variability.

I have been raising concerns3 since 2003 about how uncertainty surrounding climate change is

evaluated and communicated. The IPCC’s efforts to consider uncertainty focus primarily on

communicating uncertainty, rather than on characterizing and exploring uncertainty in a way that

would be useful for risk managers and resource managers and the institutions that fund science. A

number of scientists have argued that future IPCC efforts need to be more thorough about describing

sources and types of uncertainty, making the uncertainty analysis as transparent as possible.

Recommendations along these lines were made by the recent IAC4 review of the IPCC.

Because the assessment of climate change science by the IPCC is inextricably linked with the

UNFCCC polices, a statement about scientific uncertainty in climate science is often viewed as a

political statement. A person making a statement about uncertainty or degree of doubt is likely to

become categorized as a skeptic or denier or a “merchant of doubt,”5 whose motives are assumed to be

ideological or motivated by funding from the fossil fuel industry. My own experience in publicly

discussing concerns about how uncertainty is characterized by the IPCC has resulted in my being

labeled as a “climate heretic”6 that has turned against my colleagues.

Climate change winners and losers

A view of the climate change problem as irreducibly global fails to recognize that some regions may

actually benefit from a warmer and/or wetter climate. Areas of the world that currently cannot

adequately support populations and agricultural efforts may become more desirable in future climate

regimes.

3 http://curry.eas.gatech.edu/climate/pdf/crc-102103.pdf

4 http://reviewipcc.interacademycouncil.net/

5 Oreskes, N. and E.M. Conway, 2010: Merchants of Doubt: How a Handful of Scientists Obscured the

Truth on Issues from Tobacco to Global Warming. Bloomsbury Press, 368 pp.

6 http://www.scientificamerican.com/article.cfm?id=climate-heretic

Curry – Testimony on Rational Discussion of Climate Change

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Arguably the biggest global concern regarding climate change impacts is concerns over water

resources. This concern is exacerbated in regions where population is rapidly increasing and water

resources are already thinly stretched. China and South Asia (notably India, Pakistan, and Bangladesh)

are facing a looming water crisis arising from burgeoning population and increasing demand for water

for irrigated farming and industry. China has been damming the rivers emerging from Tibet and

channeling the water for irrigation, and there is particular concern over the diversion of the

Brahmaputra to irrigate the arid regions of Central China. China’s plans to reroute the Brahmaputra

raises the specter of riparian water wars with India and Bangladesh.

The IPCC AR4 WGII makes two statements of particular relevance to the water situation in central

and south Asia:

“Freshwater availability in Central, South, East and South-East Asia . . . is likely to decrease

due to climate change, along with population growth and rising standard of living that could

adversely affect more than a billion people in Asia by the 2050s (high confidence).”7

“Glaciers in the Himalaya are receding faster than in any other part of the world and, if the

present rate continues, the likelihood of them disappearing by the year 2035 and perhaps

sooner is very high if the Earth keeps warming at the current rate. Its total area will likely

shrink from the present 500,000 to 100,000 km2 by the year 2035 (WWF, 2005).”8

The lack of veracity of the statement about the melting Himalayan glaciers has been widely discussed,

and the mistake has been acknowledged by the IPCC.9 However, both of these statements seem

inconsistent with the information in Table 10.2 of the IPCC AR4 WG II and the statement:

“The consensus of AR4 models . . . indicates an increase in annual precipitation in most of

Asia during this century; the relative increase being largest and most consistent between

models in North and East Asia. The sub-continental mean winter precipitation will very likely

increase in northern Asia and the Tibetan Plateau and likely increase in West, Central,

South-East and East Asia. Summer precipitation will likely increase in North, South, South-

East and East Asia but decrease in West and Central Asia.” 10

Based on the IPCC’s simulations of 21st century climate, it seems that rainfall will increase overall in

the region (including wintertime snowfall in Tibet), and the IPCC AR4 WGII does not discuss the

impact of temperature and evapotranspiration on fresh water resources in this region. The importance

of these omissions, inconsistencies or mistakes by the IPCC is amplified by the potential of riparian

warfare in this region that supports half of the world’s population.

A serious assessment is needed of vulnerabilities, region by region, in the context of possible climate

change scenarios, demographics, societal vulnerabilities, possible adaptation, and current adaptation

deficits. A few regions have attempted such an assessment. Efforts being undertaken by the World

Bank Program on the Economics of Adaptation to Climate Change to assess the economics of

adaptation in developing countries are among the best I’ve seen in this regard. This is the kind of

information that is needed to assess winners and losers and how dangerous climate change might be

relative to adaptive capacities.

7 http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch10s10-es.html

8 http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch10s10-6-2.html

9 http://www.ipcc.ch/pdf/presentations/himalaya-statement-20january2010.pdf

10 http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch10s10-3.html#10-3-1

Curry – Testimony on Rational Discussion of Climate Change

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Climate surprises and catastrophes

The uncertainty associated with climate change science and the wickedness of the problem provide

much fodder for disagreement about preferred policy options. Uncertainty might be regarded as cause

for delaying action or as strengthening the case for action. Low-probability, high-consequence events

in the context of a wicked problem provide particular challenges to developing robust policies.

Extreme events such as landfalling major hurricanes, floods, extreme heat waves and droughts can

have catastrophic impacts. While such events are not unexpected in an aggregate sense, their frequency

and/or severity may increase in a warmer climate and they may be a surprise to the individual locations

that are impacted by a specific event. Natural events become catastrophes through a combination of

large populations, large and exposed infrastructure in vulnerable locations, and when humans modify

natural systems that can provide a natural safety barrier (e.g. deforestation, draining wetlands). For

example, the recent catastrophic flooding in Pakistan11 apparently owes as much to deforestation and

overgrazing as it does to heavy rainfall. Addressing current adaptive deficits and planning for climate

compatible development will increase societal resilience to future extreme events that may be more

frequent or severe in a warmer climate.

Abrupt climate change12 is defined as a change that occurs faster than the apparent underlying driving

forces. Abrupt climate change, either caused by natural climate variability or triggered in part by

anthropogenic climate change, is a possibility that needs investigation and consideration. Catastrophic

anthropogenic climate change arising from climate sensitivity on the extreme high end of the

distribution has not been adequately explored, and the plausible worst-case scenario has not be

adequately articulated. To what extent can we falsify scenarios of very high climate sensitivity based

on our background knowledge? What are the possibilities for abrupt climate change, and what are the

possible time scales involved? What regions would be most vulnerable under this worst-case scenario?

Weitzmann13 characterizes the decision making surrounding climate change in the following way:

“Much more unsettling for an application of expected utility analysis is deep structural

uncertainty in the science of global warming coupled with an economic inability to place

a meaningful upper bound on catastrophic losses from disastrous temperature changes.

The climate science seems to be saying that the probability of a system-wide disastrous

collapse is non-negligible even while this tiny probability is not known precisely and

necessarily involves subjective judgments.”

When a comprehensive decision analysis includes plausible catastrophes with unknown probabilities, the

policy implications can be radically different from those suggested by optimal decision making strategies

targeted at the most likely scenario. Weitzmann argues that it is plausible that climate change policy

stands or falls to a large extent on the issue of how the high impact low probability catastrophes are

conceptualized and modeled. Whereas “alarmism” focuses unduly on the possible (or even impossible)

worst-case scenario, robust policies consider unlikely but not impossible scenarios without letting them

completely dominate the decision.

In summary, the IPCC focus on providing information to support the establishment of an optimal CO2

stabilization target doesn’t address two important issues for driving policy:

• reducing vulnerability to extreme events such as floods, droughts, and hurricanes

• examination of the plausible worst case scenario.

11 http://judithcurry.com/2010/09/20/pakistan-on-my-mind/

12 http://www.nap.edu/openbook.php?isbn=0309074347

13 http://dash.harvard.edu/bitstream/handle/1/3693423/Weitzman_OnModeling.pdf?sequence=2

Curry – Testimony on Rational Discussion of Climate Change

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There are no “silver bullet” solutions

Xu, Crittenden et al.14 argue that “gigaton problems require gigaton solutions.” The wickedness of the

climate problem precludes a gigaton solution (either technological or political). Attempts to address

the climate change problem through a U.N. treaty for almost two decades have arguably not been

successful. The climate change problem now walks hand-in-hand with the ocean acidification

problem, the link between the two problems being the proposed stabilization of atmospheric CO2. The

proposed solution to the wicked climate problem and ocean acidification in terms of stabilization of

atmospheric CO2 has revealed and created new problems in terms of energy policy. Energy policy is

driven by a complicated mix of economics and economic development, energy security, environmental

quality and health issues, resource availability (e.g. peak oil), etc.

Even if climate change is not the primary driver in energy policy, the climate-energy nexus is a very

important one. Not just in the sense of anthropogenic climate change motivating energy policy, but

weather and climate are key drivers in energy demand and even supply. On the demand side, we have

the obvious impact of heating and cooling degree days. On the supply side, we have oil and gas supply

disruptions (e.g. hurricanes in the Gulf of Mexico) plus the dependence of hydro, solar, and wind

power on weather and climate. What is perhaps the most important connection, and one often

overlooked, is the energy-water nexus, whereby power plants requiring water for cooling compete with

domestic, agricultural, industrial, and ecosystems for the available water supply.

The complexity of both the climate and energy problems and their nexus precludes the gigaton “silver

bullet” solution to these challenges. Attempting to use carbon dioxide as a control knob to regulate

climate in the face of large natural climate variability and the inevitable weather hazards is most likely

futile. In any event, according to climate model projections reported in the IPCC AR4, reducing

atmospheric CO2 will not influence the trajectory of CO2 induced warming until after 2050. The

attempt to frame a “silver bullet” solution by the UNFCCC seems unlikely to succeed, given the size

and the wickedness of the problem. The wicked gigaton climate problem will arguably require

thousands of megaton solutions and millions of kiloton solutions.

Moving forward

Climate scientists have made a forceful argument for a looming future threat from anthropogenic

climate change. Based upon the background knowledge that we have, the threat does not seem to be an

existential one on the time scale of the 21st century, even in its most alarming incarnation. It is now up

to the political process (international, national, and local) to decide how to contend with the climate

problem. It seems more important that robust responses be formulated than to respond urgently with a

policy that may fail to address the problem and whose unintended consequences have not been

adequately explored.

The role for climate science and climate scientists in this process is complex. In the past 20 years,

dominated by the IPCC/UNFCCC paradigm, scientists have become entangled in an acrimonious

scientific and political debate, where the issues in each have become confounded. This has generated

much polarization in the scientific community and has resulted in political attacks on scientists on both

sides of the debate, and a scientist’s “side” is often defined by factors that are exogenous to the actual

scientific debate. Debates over relatively arcane aspects of the scientific argument have become a

substitute for what should be a real debate about politics and values.

14 http://www.spp.gatech.edu/faculty/marilynbrown/sites/default/files/attachment/Gigaton%20Problems

%20Need%20Gigaton%20Solutions.pdf

Curry – Testimony on Rational Discussion of Climate Change

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Continuing to refine the arguments put forward by the IPCC that focus on global climate model

simulations projections of future climate change may have reached the point of diminishing returns for

both the science and policy deliberations. Further, the credibility of the IPCC has been tarnished by the

events of the past year. It is important to broaden the scope of global climate change research beyond

its focus on anthropogenic greenhouse warming to develop a better understanding of natural climate

variability and the impact of land use changes and to further explore the uncertainty of the coupled

climate models and the capability of these models to predict emergent events such as catastrophic

climate change. And far more attention needs to be given to establishing robust and transparent climate

data records (both historical and paleoclimate proxies).

Regional planners and resource managers need high-resolution regional climate projections to support

local climate adaptation plans and plans for climate compatible development. This need is unlikely to

be met (at least in the short term) by the global climate models. In any event, anthropogenic climate

change on timescales of decades is arguably less important in driving vulnerability in most regions

than increasing population, land use practices, and ecosystem degradation. Regions that find solutions

to current problems of climate variability and extreme weather events and address challenges

associated with an increasing population will be better prepared to cope with any additional stresses

from climate change.

Hoping to rely on information from climate models about projected regional climate change to guide

adaptation response diverts attention from using weather and climate information in adaptive water

resource management and agriculture on seasonal and subseasonal time scales. Optimizing water

resource management and crop selection and timing based upon useful probabilistic subseasonal and

seasonal climate forecasts has the potential to reduce vulnerability substantially in many regions. This

is particularly the case in the developing world where much of the agriculture is rain fed (i.e. no

irrigation). It would seem that increasing scientific focus on seasonal and subseasonal forecasts could

produce substantial societal benefits for tactical adaptation practices.

The global climate modeling effort directed at the IPCC/UNFCCC paradigm has arguably reached the

point of diminishing returns in terms of supporting decision making for the U.N. treaty and related

national policies. At this point, it seems more important to explore the uncertainties associated with

future climate change rather than to attempt to reduce the uncertainties in a consensus-based approach.

It is time for climate scientists to change their view of uncertainty: it is not just something that is

merely to be framed and communicated to policy makers, all the while keeping in mind that doubt is a

political weapon in the decision making process. Characterizing, understanding, and exploring

uncertainty is at the heart of the scientific process. And finally, the characterization of uncertainty is

critical information for robust policy decisions.

Engagement of climate researchers with regional planners, economists, military/intelligence

organizations, development banks, energy companies, and governments in the developing world to

develop a mutual understanding about what kind of information is needed can promote more fruitful

decision outcomes, and define new scientific challenges to be addressed by research. The need for

climate researchers to engage with social scientists and engineers has never been more important.

Further, there is an increasing need for social scientists and philosophers of science to scrutinize and

analyze our field to prevent dysfunction at the science-policy interface.

And finally, climate scientists and the institutions that support them need to acknowledge and engage

with ever-growing groups of citizen scientists, auditors, and extended peer communities that have

become increasingly well organized by the blogosphere. The more sophisticated of these groups are

challenging our conventional notions of expertise and are bringing much needed scrutiny particularly

Curry – Testimony on Rational Discussion of Climate Change

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into issues surrounding historical and paleoclimate data records. These groups reflect a growing public

interest in climate science and a growing concern about possible impacts of climate change and

climate change policies. The acrimony that has developed between some climate scientists and

blogospheric skeptics was amply evident in the sorry mess that is known as Climategate. Climategate

illuminated the fundamental need for improved and transparent historical and paleoclimate data sets

and improved information systems so that these data are easily accessed and interpreted.

Blogospheric communities can potentially be important in identifying and securing the common

interest at these disparate scales in the solution space of the energy, climate and ocean acidification

problems. A diversity of views on interpreting the scientific evidence and a broad range of ideas on

how to address these challenges doesn’t hinder the implementation of diverse megaton and kiloton

solutions at local and regional scales. Securing the common interest on local and regional scales

provides a basis for the successful implementation of climate adaptation strategies. Successes on the

local and regional scale and then national scales make it much more likely that global issues can be

confronted in an effective way.

Curry – Testimony on Rational Discussion of Climate Change

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Short Biography

Judith Curry

Chair and Professor, School of Earth and Atmospheric Sciences

Georgia Institute of Technology

Atlanta, GA 30332-0349

curryja@eas.gatech.edu

Dr. Judith Curry is Professor and Chair of the School of Earth and Atmospheric Sciences at the

Georgia Institute of Technology and President of Climate Forecast Applications Network

(CFAN). Dr. Curry received a Ph.D. in atmospheric science from the University of Chicago in

1982. Prior to joining the faculty at Georgia Tech, she has held faculty positions at the University

of Colorado, Penn State University and Purdue University. Dr. Curry’s research interests span a

variety of topics in climate; current interests include air/sea interactions, climate feedback

processes associated with clouds and sea ice, and the climate dynamics of hurricanes. She is a

prominent public spokesperson on issues associated with the integrity of climate science, and has

recently launched the weblog Climate Etc. Dr. Curry currently serves on the NASA Advisory

Council Earth Science Subcommittee and has recently served on the National Academies Climate

Research Committee and the Space Studies Board, and the NOAA Climate Working Group. Dr.

Curry is a Fellow of the American Meteorological Society, the American Association for the

Advancement of Science, and the American Geophysical Union.

.

For more information:

http://curry.eas.gatech.edu/

http://www.cfanclimate.com/

http://judithcurry.com

Wikipedia: http://en.wikipedia.org/wiki/Judith_Curry

Sourcewatch: http://www.sourcewatch.org/index.php?title=Judith_Curry