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              Table
              of Contents & front matter
              Overview
              
              
              The current financial crisis cannot be an excuse to put climate on the back burner. 
              On average, a financial crisis lasts less than two years and results in a 3 percent
               loss in gross domestic product (GDP) that is later offset by more than 20 percent 
               growth over eight years of recovery and prosperity. So for all the harm they cause, 
               financial crises come and go. Not so with the growing threat imposed by a changing climate. Why?
Because time is not on our side. The impacts of greenhouse gases released into the atmosphere will be felt 
for decades, even millennia, making the return to a “safe” level very difficult. This inertia in the climate
system severely limits the possibility of making up for modest efforts today with accelerated mitigation 
in the future. Delays also increase the costs because impacts worsen and cheap mitigation options disappear
as economies become locked into high-carbon
infrastructure and lifestyles—more inertia.
Immediate action is needed to keep warming as close as possible to 2°C. That amount of warming is 
not desirable, but it is likely to be the best we can do. There isn’t a consensus in the economic 
profession that this is the economic optimum. There is, however, a growing consensus in policy and 
scientific circles that aiming for 2°C warming
is the responsible thing to do. This Report endorses such a position. From the perspective 
of development, warming much above 2°C is simply unacceptable. But stabilizing
at 2°C will require major shifts in lifestyle, a veritable energy revolution, and a 
transformation in how we manage land and forests. And substantial adaptation would still 
be needed. Coping with climate change will require all the innovation and ingenuity
that the human race is capable of.
              
              
              1.
              Understanding the links between climate change and development
              
              
              Societies have always depended on the climate but are only now coming to grips with 
              the fact that the climate depends on their actions. The steep increase in greenhouse
gases since the Industrial Revolution has transformed the relationship between people and the environment. 
In other words, not only does climate affect development
but development affects the climate.
Left unmanaged, climate change will reverse development progress and compromise
the well-being
of current and future generations. It is certain that the earth will get warmer on average, 
at unprecedented speed. Impacts will be felt everywhere, but much of the damage will be in 
developing countries. Millions of people from Bangladesh
to Florida will suffer as the sea level rises, inundating settlements and contaminating
freshwater. Greater rainfall variability
and more severe droughts in semiarid Africa will hinder efforts to enhance food security 
and combat malnourishment.5 The hastening disappearance of the Himalayan and Andean glaciers—which 
regulate river flow, generate hydropower, and supply clean water for over a billion of people on farms
 and in cities—will threaten rural livelihoods
and major food markets (map 1.1).
That is why decisive, immediate action is needed. Even though the debate about the costs 
and benefits of climate change mitigation continues, the case is very strong for immediate
 action to avoid unmanageable
increases in temperature. The unacceptability
of irreversible and potentially catastrophic impacts and the uncertainty about how, and how soon, they could occur
              
              
              Focus
              A: the science of climate change
              
              
              The climate is changing—that is now indisputable. There is a scientific consensus that the world 
              is becoming a warmer place principally attributable to human activities. In the words of the 
              Intergovernmental Panel on Climate Change (IPCC) in its fourth assessment report:
               “Warming of the climate system is unequivocal.”1 For nearly 1 million years before 
               the Industrial Revolution, the carbon dioxide (CO2) concentration in the atmosphere 
               ranged between 170 and 280 parts per million (ppm). Levels are now far above that 
               range—387 ppm—higher than the highest point in at least the past 800,000 years, 
               and the rate of increase may be accelerating.2 Under high-emissions
scenarios, concentrations by the end of the 21st century could exceed those experienced on 
the planet for tens of millions of years.
              
              
              Part I
              2.
              Reducing human vulnerability: helping people help themselves
              
              
              Further climate change is unavoidable. It will stress people physically and economically, 
              particularly in poor countries. Adapting requires robust decision making—planning over 
              a long time horizon and considering a broad range of climate and socioeconomic scenarios. 
              Countries can reduce physical and financial risks associated with variable and extreme weather.
               They can also protect the most vulnerable. Some established practices will have to be 
               expanded—such as insurance and social protection—and others will have to be done
                differently—such as urban and infrastructure planning. These adaptation actions
                 would have benefits even without climate change. Promising initiatives are emerging, 
                 but applying them on the necessary scale will require money, effort, ingenuity, and information.
              
              
              Focus
              B: Biodiversity and ecosystem services in a changing climate
              
              
              Earth
supports a complex web of 3 million to 10 million species of plants and animals and an even greater number of microorganisms.
For the first time a single species, humankind, is in a position to preserve or destroy the very functioning of that
              web.  In people’s daily lives only a few species appear to matter. A few dozen species provide most basic nutrition—20 percent of human calorie intake comes from
              rice, 20 percent comes from wheat; a few species of cattle, poultry, and pigs supply 70 percent of animal protein. Only among the 20 percent of animal protein from fish and shell fish is a diversity of dietary species
              found. Humans are estimated to appropriate a third of the Sun’s energy that is converted to plant
              material.
              But human well-being
depends on a multitude of species whose complex interactions within well-functioning
ecosystems purify water, pollinate flowers,
decompose wastes, maintain soil fertility, buffer water flows and weather extremes, 
and fulfill social and cultural needs, among many others (box FB.1). 
The Millennium Ecosystem Assessment concluded that of 24 ecosystem services examined, 15 are being degraded or used unsustainably (table FB.1). The main drivers of degradation are land-use
conversion, most often to agriculture
or aquaculture; excess nutrients; and climate change. Many consequences 
of degradation are focused in particular regions, with the poor disproportionately
affected because they depend most directly on ecosystem services.
              
              
              3.
              Managing land and water to feed nine billion people and protect
              natural systems
              
              
              Climate change will make it harder to produce enough food for the world’s 
              growing population, and will alter the timing, availability, and quality of 
              water resources. To avoid encroaching into already-stressed ecosystems, 
              societies will have to almost double the existing rate of agricultural
productivity growth while minimizing the associated environmental damage. This requires
 dedicated efforts to deploy known but neglected practices, identify crop varieties able
  to withstand climate shocks, diversify rural livelihoods, improve management of forests,
   and invest in information systems. Countries will need to cooperate to manage shared water 
   resources and fisheries and to improve food trade. Getting basic policies right matters,
    but new technologies and practices are also emerging. Financial incentives will help. 
    Some countries are redirecting their agricultural subsidies to support environmental 
    actions, and future credits for carbon stored in trees and soils could benefit
     emission reductions and conservation goals.
              
              
              4.
              Energizing development without compromising the climate
              
              
              Solving the climate change problem requires immediate action in all countries and a fundamental
transformation of energy systems—significant improvement in energy efficiency, a dramatic shift 
toward renewable energy and possibly nuclear power, and widespread use of advanced technologies
 to capture and store carbon emissions. Developed countries must lead the way and drastically cut 
 their own emissions by as much as 80 percent by 2050, bring new technologies to market, and help 
 finance developing countries’ transition onto clean energy paths. But it is also in developing
  countries’ interests to act now to avoid locking into high-carbon infrastructure. Many changes—such 
  as removing distortionary price signals and increasing energy efficiency—are 
  good both for development and the environment.       
              
              Part II
              5.
              Integrating development into a global climate regime
               
              
              A global problem on the scale of climate change requires international coordination. Nevertheless,
implementation depends on actions within countries. Therefore, an effective international 
climate regime must integrate development concerns, breaking free of the environment-versus-equity dichotomy. 
A multitrack framework for climate action, with different goals or policies for developed 
countries and developing countries, may be one way to move forward; this framework would
 need to consider the process for defining and measuring success. The international 
 climate regime will also need to support the integration of adaptation into development.
              
              
              Focus
              C: Trade and climate change
              
              The interaction between the international trade and climate change regimes
               has potentially major implications for developing
countries. While there are positive reasons for exploring synergies between the two 
regimes and for aligning policies that could stimulate production, trade, and investment 
in cleaner technology options, instead much focus has been on using trade measures as 
sanctions in the global climate negotiations.
              
              
              
              6.
              Generating the funding needed for mitigation and adaptation
               
              
              Developed countries must take the lead in combating climate change. 
              But mitigation will be neither effective nor efficient without abatement 
              efforts in developing countries.
Those are two key messages of earlier chapters. But there is a critical third dimension 
to meeting the climate challenge: equity. An equitable approach to limiting global 
emissions of greenhouse gases has to recognize that developing countries have legitimate
 development needs, that their development may be jeopardized by climate change, and that
  they have contributed little, historically, to the problem.
Flows of climate finance, both fiscal transfers and market transactions, 
from developed to developing countries represent
the principal way to reconcile equity with effectiveness and efficiency 
in dealing with the climate problem. Financial flows can help developing
 countries reduce their greenhouse gas emissions and adapt to the effects of 
 climate change. In addition, there will be financing needs related to developing
  and diffusing new technologies. Mitigation, adaptation, and the deployment of 
  technologies have to happen in a way that allows developing countries to continue 
  their growth and reduce poverty. This is why additional financial flows to developing
countries are so crucial.
The funding required for mitigation, adaptation, and technology is massive. In 
developing countries mitigation could cost $140 to $175 billion a year over the 
next 20 years (with associated financing needs of $265 to $565 billion); over the 
period 2010 to 2050 adaptation investments could average $30 to $100 billion a year
 (in round numbers). These figures can be compared with current development assistance 
 of roughly $100 billion a year. Yet efforts to raise funding for mitigation and 
 adaptation have been woefully inadequate, standing at less than 5 percent of projected needs.
              
              
              7.
              Accelerating innovation and technology diffusion
               
              
              Windmills peppered European
landscapes to provide
energy for agricultural activities long before the discovery
of electricity. Thanks to the forces of innovation and technology diffusion,
 wind is now powering the first stages of what could become a veritable energy 
 revolution. Between 1996 and 2008 the global installed wind capacity increased 
 twentyfold to stand at more than 120 gigawatts, displacing an estimated 158 million 
 tons of carbon dioxide
(CO2) a year while creating some 400,000 jobs (figure 7.1).1 Much of this growth 
is attributable to government incentives and to publicly and privately funded 
research, driving down the cost of wind technology and driving up efficiency.
And although most installed capacity is in Europe and the United States, the pattern
is shifting. In 2008 India and China each installed more wind capacity than any other 
country except the United States, and together they host nearly 20 percent of the world’s 
capacity. An Indian company, Suzlon, is one of the world’s leading wind turbine manufacturers, 
employing 13,000 people across Asia. So the global takeoff of wind technology is setting an early precedent
for climate-smart
development. And complementary advances, such as global geospatial
 wind resource information, are making siting decisions easier (map 7.1).
              
              
              8.
              Overcoming behavioral and institutional inertia
               
              
              Achieving results in tackling the climate challenge requires going beyond 
              the international mobilization of finance and technology, by addressing 
              the psychological, organizational, and political barriers to climate action.
               These barriers stem from the way people perceive and think about the climate
                problem, the way bureaucracies work, and the interests shaping government action. 
                Policy change requires shifting political incentives and even organizational responsibilities.
And it requires the active marketing of climate policies, tapping into social norms and behaviors,
 in order to translate the public’s concern into understanding and understanding into action—starting at home.
              
              
              Glossary
              Selected
              Development Indicators                              
              Charts
              and Graphics