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Bulletin
of the
Atomic
Scientists
IT IS 5 MINUTES TO MIDNIGHT
®
Feature
Getting serious about the
new realities of global
climate change
Jennifer A. Burney, Charles F. Kennel, and
David G. Victor
Abstract
For two decades, the central challenge facing climate-change policy makers involved efforts to control emis-
sions of carbon dioxide. While diplomats looked at many different global-warming pollutants, they designed
rules that mostly focused on carbon dioxide. Unfortunately, those efforts have largely failed, which has
created yet another difficult challenge for the global community: how to manage the severe impacts of a
warming world. New diplomatic strategies are needed. Diplomats must work harder on pollutants other than
carbon dioxideÑsuch as sootÑthat will be easier to regulate and can help build credibility in the international
diplomatic regime. New science shows that soot and short-lived climate pollutants actually cause almost half
of current global warmingÑmuch more than thought just a few years ago. Fortuitously, these pollutants are
also relatively easy to manage, and success on this front will help catalyze the political support needed for the
much more difficult, yet essential, task of making deep cuts in carbon dioxide. At the same time, new thinking
will be needed on how to help societies adapt, the authors write, such as building networks of experts and local
officials who are on the front lines of adaptation.
Keywords
carbon dioxide, climate change, emissions, environment, legislation, politics, short lived climate pollutants
S
ince 1989, diplomats from around
the world have been working to
craft agreements to manage the
threats associated with global climate
change. Their efforts have produced
the 1992 United Nations Framework
Convention on Climate Change and the
1997 Kyoto Protocol. The central obliga-
tions under the original Kyoto treaty
expired in 2012, but late last year many
countries agreed to extensions out to the
year 2020. A new round of talks is also
under way to develop yet another treaty.
Along the way there have been numer-
ous communiquŽs, initiatives, and other
grand-sounding programs aimed at miti-
gating the emissions that are now chan-
ging the global climate in increasingly
visible ways.
While diplomacy hasnÕt been in short
supply, it hasnÕt had much practical im-
pact on the rate of emissions. Worldwide,
Bulletin of the Atomic Scientists
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carbon dioxide and other greenhouse-
gas pollution is at its highest level ever.
Emissions of all these gases in 2010 were
31 percent above 1990 levels and still
rising, even though emissions would
need to be cut 50 to 80 percent over the
next few decades to stabilize the climate
(JRC/PBL, 2011). The worldÕs energy and
agricultural systemsÑthe main causes of
human emissions of warming gasesÑare
pointed severely in the wrong direction.
The countries that agreed to make
substantive cuts in emissions under the
original Kyoto Protocol accounted for
just 60 percent of world emissions; by
the time the treaty was ratified, however,
that number fell to less than one-quarter.
The new, extended Kyoto treaty covers
just 14 percent of world emissions.1
Worse, most of the few areas of appar-
ent progress are illusions. Across the
industrialized world, governments are
celebrating the fact that emissions are
now declining slightly. Much of that
achievement, however, stems from fac-
tors like the collapse and restructuring
of Eastern Europe or the unexpected
appearance of cheap and clean natural
gas from shale in the United StatesÑ
developments that have no relationship
to treaties on global warming. Few coun-
tries have intentionally made substantial
cuts in emissions, and no major econ-
omy is even close to being on track for
cuts between 50 and 80 percent. Even
the paragons of greenery are doing less
than meets the eye to address a problem
they consider extremely serious. For ex-
ample, since 1990, emissions from Brit-
ain have declined by one-fifth, but that
big reduction disappears when emissions
from all the products that Britons import
are considered. Such ÒdisplacementÓ of
emissions is rampantÑapproximately one-
quarter of global carbon dioxide emissions
are embodied in traded goods (Davis et al.,
2011). Because climate treaties specify that
nations report emissions occurring only
within their own sovereign borders, such
national accounting games do not change
the global calculus. That is, globalization
has made it harder to get serious about cli-
mate change because it has made it easier
for nations to shift emissions to those coun-
tries where limits are more lax.
Meanwhile, many emerging econo-
mies have been growing rapidly, mainly
powered by the most emission-intensive
of all fossil fuels: coal (Victor and Morse,
2009). Indeed, most future projections
suggest that all growth in emissions will
come from these countries. The Interna-
tional Energy Agency in Paris, for exam-
ple, projects that 60 percent of emissions
growth between now and 2035 will come
from one coal-intensive country alone:
China (IEA, 2012). Looking at such fore-
casts, the rich industrialized countries
blame developing countries for their
failure to restrain their emissions; the
developing countries blame the indus-
trialized world for failing to acknow-
ledge its historical responsibility for
most of the warming societies are com-
mittedtotoday.Neither wantstotakethe
lead without the other. In all this diplo-
matic gridlock, the only clear fact is that
theclimateiswarmingandpoisedtogeta
lot warmer.
It is time to face new realities
and shift strategies
Two decades ago the central challenge
for policy makers was to coordinate eff-
orts to control emissions. They failed.
That challenge remains, but now there
is a new one: managing the economic
and social risks of unchecked climate
change that have emerged because the
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world missed the chance to act early.
Getting serious about these twin chal-
lenges will require a new mind-set. It
will also require engaging new actors
in the policy process.
Efforts are needed on two fronts
First, diplomats must fix the central
problem in international climate talks:
low credibility. ThereÕs no question
that climate change is one of the hardest
problems that the international commu-
nity has ever faced (Victor, 2011), but
international negotiators have unwit-
tingly made a difficult problem even
more so by focusing heavily on one pol-
lutant: carbon dioxide. While it is true
that the Kyoto treaty covers multiple
pollutants, what countries actually em-
phasize when monitoring and reportingÑ
that is, the accounting system that gov-
erns the Kyoto capsÑare long-lived pol-
lutants, particularly carbon dioxide.
Those choices reflected good intentions
at the time. However, while no climate
solution is possible without solving the
problem of carbon dioxide, the seem-
ingly exclusive emphasis on this green-
house gas has diverted attention from
other ways in which near-term progress
to slow climate change is greater.
The politics of getting to long-term
solutions requires tackling a cruel
logic. Carbon dioxide lasts more than a
century in the atmosphere (and when
dissolved in the oceans lasts 1,000
years) (Solomon et al., 2009). Any pro-
gram to cut carbon dioxide will be
expensive since most carbon emissions
come from burning fossil fuels and alter-
natives arenÕt ready at scale. And even if
those big costs are paid, there will be no
tangible impact on climate warming for
decades. Societies, as a general rule,
arenÕt good at tackling problems that
have high immediate costs, require sus-
tained effort over decades, and provide
few tangible benefits to those who must
first bear the costs.
Boosting credibility therefore re-
quires focusing on parts of the climate
problem where reasonably quick, tan-
gible success is possible. Some opportu-
nities to do this exist. Over the past few
years, scientists in San DiegoÑworking
with colleagues around the worldÑhave
suggested a strategy to achieve visible
results in a few years: launch an aggres-
sive program to tackle soot and other
short-lived climate pollutants (Molina
et al., 2009; Shindell et al., 2012; Victor
et al., 2012; Wallack and Ramanathan,
2009). It has become clear that these pol-
lutantsÑsoot in particularÑplay a much
larger role in changing the climate than
was thought five years ago (Bond et al.,
2013; Jacobson, 2001; Ramanathan and
Carmichael, 2008; Ramanathan and
Feng, 2008). Slightly less than half of
current global warming is due to four
categories of non-carbon dioxide pollu-
tants: dark soot particles often called
black carbon, methane gas, lower atmos-
pheric ozone, and industrial gases such
as the hydrofluorocarbons used as cool-
ants. Nearly all have life spans of a few
weeks to a decade, much shorter than
carbon dioxide. Yet they are potent war-
mers. Emitting one ton of black carbon,
for example, has the same immediate
effect on warming as emitting 500 to
2,000 tons of carbon dioxide.
A second front in a new climate-
policy strategyÑadaptationÑis also es-
sential. Reducing emissions largely fails
without international coordination, but
the politics of adaptation to the effects
of climate change is quite different.
Almost all adaptation is a solitary act.
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Each country or city or neighborhood
can make the calculus on its own.
Whether San Diego builds seawalls,
nourishes its beaches to compensate
for sand lost to higher seas, or improves
wildfire management is mainly a calcu-
lation that San Diegans make (San Diego
Foundation, 2012). The costs are in-
curred locally, and so are the benefits.
For years it has been taboo to talk
about adaptation because advocates for
climate mitigation feared that adapta-
tion signaled defeat; once politicians
started bracing for climate change, they
wouldnÕt focus on mitigation (Pielke
et al., 2007). This ÒcanÕt walk and chew
gumÓ theory of politics has always been
wrong and yet is very popular among
analysts and activists because it leads
to simple advice for politicians. (It has
also been applied to short-lived climate
pollutantsÑto this day, many advocates
for action on carbon dioxide abhor dis-
cussion of short-lived pollutants based
on the warped logic that those pollutants
will distract politicians from the need to
cut carbon dioxide.)
These amateurish theories fail to take
into account that politics isnÕt a zero-
sum game. Decades of failed diplomacy
have done little but foster disbelief in
the possibility of success in fighting
climate change. And pretending that
adaptation is not a looming challenge
has just made the impacts of climate
change even more dangerous for unpre-
pared societies.
Getting results with short-lived
climate pollutants
The perennial failure to get much done
in climate diplomacy is now feeding on
itself. When major diplomatic events
like the 2009 Copenhagen conference
end in failure, people lose faith that ser-
ious solutions are feasible. Firms no
longer believe that regulation of cli-
mate-altering gases is inevitable, and
they cut back on clean-energy research
and development. Politicians think they
can ignore the problem without much
public reproachÑas is evident espe-
cially in the United States, which has
historically led on so many other inter-
national environmental issues but lags
conspicuously on climate change. Envir-
onmental groups pare back climate-
advocacy efforts and start talking about
other topics, like energy security, while
hoping that the climate agenda can be
sneaked in. Even individual consumers
throw up their hands: Why bother
making climate-conscious (and often
more expensive) choices with no sign
of support from leaders or institutions?
Failure begets failure.
Dealing with short-lived climate pol-
lutants can bring visible success to the
climate-change fight because the politics
of managing these pollutants is easier for
most countries to fathom. For example,
managing the most noxious short-lived
climate pollutants goes hand in hand
with improving local air quality (Barker
et al., 2007). Because methane, ozone,
and aerosols interact with one another,
a change in the concentration of one
changes the others. Methane, a precursor
of tropospheric ozone, is a major pollu-
tant and threat to human health as well as
a strong warming agent;similarly, sulfate
pollutants affect the warming rate from
black carbon (Ramana et al., 2010). Thus,
when air-quality managers act to reduce
theformsofairpollution theyarealready
familiar with, they also have a large
impact on climate change and improve
public health and agriculture (Auff-
hammer et al., 2006). In short, efforts to
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cut short-lived climate pollutants yield
tangible, local benefits that can help
even reluctant nations take action. The
other bit of good news is that scientists
have learned many new ways to regulate
short-lived pollutants.
Societies know how to make deep cuts
in soot because a few have already done
so. For example, CaliforniaÕs successful
program to limit emissions from diesel
engines, power plants, and other sooty
sources cut black-carbon emissions in
half in just two decades. The costs of
soot emissions reduction are not zero,
but they are manageable (EPA, 2005;
UNEP, 2011). These dramatic reductions
were achieved through a suite of policies
that capped particulate-matter emissions
across vehicle types and encouraged use
ofdieselparticulatefiltersandalternative
fuels. In China and India, perhaps the
worldÕs biggest emitters of soot, emission
controls will be even cheaper, because
those countries can start by making the
least expensive cuts while also taking
advantage of technologies already devel-
oped elsewhere in the world.
While the stars are now aligning for
serious action on short-lived climate
pollutants, efforts to manage carbon
dioxide remain mired in political diffi-
culties. Until new technologies are
available and international institutions
build much higher credibility, efforts to
manage this greenhouse gas will involve
swimming upstream against heavy polit-
ical currents. Not only are the costs and
benefits of carbon controls mismatched
in time, but the geography of costs and
benefits is also toxic to politicians. Most
of the harm caused by each nationÕs
carbon dioxide is felt in other countries.
Each nation, thinking about its own
costs and benefits, becomes reluctant
to take action on carbon dioxide unless
confident that all others are engaged in a
similar program. Getting serious about
cutting soot and other short-lived cli-
mate pollutants wonÕt be easy, but the
effort is less likely to be derailed by self-
ish, short-sighted logic. Much of the
harm from short-lived climate pollutants
is felt within each nation, and so is much
of the benefit of reductions.
In part, the gridlock on global warm-
ingforthepasttwodecadesreflectsbasic
political logic. Climate scientists, wor-
ried about long-term global warming,
have asked politicians to take heroic
actions that no one keen on re-election
would be wise to embrace. Instead
of imagining politics in the mode of
Mr. Smith Goes to Washington, a smarter
strategy finds ways to align the climate
problem with the logic of real-world pol-
itics. Short-lived climate pollutants can
help immensely on that front, because
the political logic for action on soot and
other such pollutants involves swim-
ming with the current.
Success with short-lived climate pol-
lutants can help fix the problem of cred-
ibility in international climate-change
policy. By demonstrating that countries
can work together to make visible im-
provements to the climate, mitigation of
short-lived climate pollutants can help
build credibility along with practical
experience that will be essential for the
much harder problem of tackling carbon
dioxide. Working hard on these short-
lived emissions, starting now, is not a
substitute for serious action on long-
lived pollutants like carbon dioxide. Poli-
tically and environmentally they are
complements; swift action on short-
lived climate pollution could slow by a
few decades some of the more severe
effects of climate warming, such as a
rise in sea level (Hu et al., 2013).
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Adaptation is not a
four-letter word
After decades of inaction, the planet is
nearing the cusp of what may be major
tipping points in the climate system. For
example, by increasing the absorption of
sunlight by the Arctic Ocean, the retreat
of Arctic sea ice and snow cover is chan-
ging the pattern of polar warming and
increasing its rate. The consequences for
weather patterns around the world are
beginning to be felt (Liu et al., 2012;
Screen and Simmonds, 2010). By working
to cut short-lived climate pollutants, major
countries can delay these and other recon-
figurations of the climate system. Even so,
the need for adaptation is inescapable.
Climate adaptation isnÕt a discrete act.
Done well, it is part of an overall risk-
management strategy. Risk is conven-
tionally defined as the product of the
probability of a given event and the mag-
nitude of its impact. For decades, climate-
change policy makers have focused on the
first part of the equation, by focusing on
mitigation. While continued efforts to
reduce the probability of catastrophic cli-
mate changes remain essential, it is foolish
to ignore the second factor. Adaptation
helps cut the costs of climate warming,
which is critical for reducing the human
toll of climate change.
Because adaptation to climate change
is mostly an intensely local activity, it
has a cruel political logic of its ownÑa
logic that has profound implications for
climate policy. The countries most vul-
nerable to changing climate tend to be
poor. Poor countries have fewer re-
sources to invest in adaptation; their
economies also tend to be based more
heavily on agriculture, the economic
sector most immediately vulnerable to
changes in climate and weather. The
poor countries by and large are least
responsible for causing climate change
in the first place, but they find them-
selves on the front lines of an economic
disaster they didnÕt create.
There is a compelling moral argument
to help these countries adapt. Just send-
ing money, however, isnÕt very practical.
Most adaptation involves things that
countries should do anywayÑfor exam-
ple, some are already investing in better
storm-warningandcrop-forecasting sys-
tems, since those help farmers and others
on the front lines deal with the vagaries
of weather while, over the long term,
probably also make them more adaptive.
Calculating the Òagreed incremental
costÓ of those programsÑthe normal
standard for international financing,
widely used in other international envir-
onmental treatiesÑis all but impossible.
WhatÕs needed, instead, is a big invest-
ment to help spread information about
best practicesÑan idea that in other stu-
dies has been called Òknowledge action
networksÓ (Kennel et al., 2012). Direct
technical funding also plays a role, but
effective organization of knowledge-
sharing is the key missing ingredient
(Kennel, 2009; Kennel and Daultrey,
2010; Rosenzweig and Wilbanks, 2010).
If, or when, it appears that warming is
too rapid and the costs of adjustment too
great, then even more aggressive efforts
to mitigate emissions will be needed.
Here, too, short-lived climate pollutants
have a prominent role to play. Cutting
them is the only means of mitigation
that can slow warming on a time scale
that is relevant for practical adaptation.
Indeed, delaying some climate impacts
by just a decade or two could make adap-
tation much more tractable, because
it would allow adjustments with the
normal turnover of human infrastructure.
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Asking cities to deal with imminent unex-
pected impacts from higher sea levels and
storms, or changing agricultural methods
under similar hurried conditions, is
expensive. Given enough time, the costs
can be folded into infrastructure and
maintenance budgetsÑan outcome that
is not just economically more efficient
but also politically more feasible. And
systems made more resilient will prob-
ably perform better, day by day.
Getting serious about climate risk
management will also require looking
closely at other taboos, such as those
related to geoengineering. In an emer-
gency, the ability to quickly respond to
climate change with crude offsetting
measuresÑfor example, injecting re-
flective particles into the upper atmos-
phere to cool the planet, as volcanoes
do periodicallyÑcould be useful. Such
measures are fraught with the danger
of unintended consequences, but un-
checked catastrophic changes in climate
could be even worse. The odds of truly
catastrophic changes in climate are
rising, and the world needs insurance
against truly horrible outcomes (Parson
and Keith, 2013; Victor et al., 2009).
The new realities of climate change,
however, are first and foremost political
in impact. For years, it has been conveni-
ent for both deniers and activists to
focus on science (Oreskes and Conway,
2010). Deniers have set standards for sci-
entific proof that canÕt be met, while sup-
porters have claimed that the science is
so ÒsettledÓ that no further motivation
for action is needed. Deniers claim that
the science is full of holes, not good
enough to prompt immediate action.
Supporters of action react by redoubling
their efforts to bolster the scientific case.
Indeed, each successive report from the
Intergovernmental Panel on Climate
ChangeÑthe international body that
does a full assessment of climate science
every five to seven yearsÑhas made
increasingly definitive warnings. If those
warnings were sufficient, there would
have been political action already. In prac-
tically every grand and difficult topic in
science, the experts disagree on many
matters. Scientific uncertainties are not
cause for paralysis. Instead, they are fun-
damental to understanding the chal-
lenges of climate change as matters of
risk management.
Inaction on climate change reflects
the lack of a political strategy that
rewards those who take action; it is not
the product of scientific doubt. The
beauty of science is that it is never
settled; last yearÕs results are precursors
to next yearÕs discoveries. The trick for
climate scientists of the warming gener-
ationÑjust as it was for the atomic scien-
tists of the bomb generationÑis to marry
good science with smart politics.
Funding
David G. Victor leads the Laboratory on International
Law and Regulation at the School of International
Relations and Pacific Studies and is funded by the
University of California, San Diego; BP PLC; the Elec-
tric Power Research Institute; and the Norwegian
Research Foundation. Charles F. Kennel is funded
by the University of California; Jennifer A. Burney
is funded by the University of California and the
Center on Food Security and the Environment at
Stanford University.
Note
1. See United Nations (1997, 2012) and BP
(2012). Fractions computed based on carbon
dioxide emissions data reported in BP (2012)
for emissions from fossil fuels. If carbon
dioxide emissions from changes in land use,
such as deforestation, were included, the
coverage of Kyoto would be proportionally
smaller.
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Author biographies
Jennifer A. Burney is an assistant professor
at UC San Diego, where her research focuses
on simultaneously achieving global food secur-
ity and mitigating climate change. A physicist
by training, she is particularly interested in the
science, technology, and policy of short-lived
climate pollutants and the role that mitigation
of these compounds can play in meeting both
climate and food security objectives.
Charles F. Kennel was educated in astronomy
and astrophysics at Harvard and Princeton and
taught physics at UCLA for many years. He
became the ninth director of the Scripps Insti-
tution of Oceanography and Vice Chancellor
and Dean of Marine Sciences at UC San Diego
in 1998, stepping down in late 2006. In 2005,
Kennel founded the UC San Diego Environ-
ment and Sustainability Initiative, embracing
teaching, research, campus operations, and
public outreach. He is now professor emeritus
at Scripps, as well as a visiting fellow at Christ's
College, Cambridge.
David G.Victor is a professor at the School of
International Relations and Pacific Studies at
the University of California, San Diego, and dir-
ector of the schoolÕs new Laboratory on Inter-
national Law and Regulation. His research
focuses on how the design of regulatory law
affects issues such as environmental pollution
and the operation of major energy markets.
Prior to joining the faculty at UC San Diego,
Victor served as founding director of the Pro-
gram on Energy and Sustainable Development
at Stanford University, where he was also a pro-
fessor at Stanford Law School.
Burney et al. 9