Michael C. MacCracken and John C. Topping, Jr
Heat waves. Drenching rains. Disappearing glaciers and retreating Arctic sea ice. Drought and extensive wildfires in the western US. Ice shelf collapse. Melting near the top of the Greenland Ice Sheet. Unprecedented occurrence of powerful hurricanes causing extensive coastal erosion. An increased rate of sea level rise. Deforestation, land cover change and loss of species. Headline after headline reporting on global warming and the changing climate. Are we experiencing just natural fluctuations, or are human activities at least in part, and perhaps in large part, responsible for these events? What more can lie ahead?
In celebration of its 20th Anniversary, the Climate Institute organized the Washington Summit on Climate Stabilization (hereafter, the Summit) to assess the likelihood that human activities are tipping, or near to tipping, the world towards abrupt and highly disruptive climate change. On 19-20 September 2006, with additional workshops on the preceding and following days, the Summit brought together approximately 150 experts in the fields of climate change, environmental and societal impacts, adaptation, and technological, institutional and societal mitigation options. Throughout the Summit, participants explored the present and projected implications of human activities on the environment and reviewed a number of the creative responses that, if implemented more widely, could help the world avoid potentially catastrophic changes in the climate and our environment.
Scientific studies, summarized and evaluated most comprehensively and credibly in the periodic assessments prepared by the UN-sponsored Intergovernmental Panel on Climate Change (IPCC), project that continuing reliance on fossil fuels to supply most of the world's energy will lead to an increase in the global average surface temperature of roughly 1.4 to 5.5°C (about 2.5 to 10°F) by the year 2100, adding to the observed increase of about 0.6°C (about 1.1°F) over the 20th century.
Given that the fall of 2006 (and 2007) were several degrees warmer than normal over much of the US, why should the world be so concerned about a projected global average temperature increase of 'only' a few degrees over the course of the 21st century? Are not climatic conditions that the world will face in 100 years similar to the conditions that prevail several hundred miles to the south? Why should we be concerned if the climate of Washington DC becomes like that of Atlanta, or even Miami? With daily temperature variations being roughly 10°C (18°F) or more, and winter-to-summer differences in the daily average temperature being about 20°C or more (roughly 36°F), can societies not, over time, redesign their buildings and infrastructure to readily adapt to a few degree rise in the annual average temperature? Why is there so much concern?
The first reason for concern is that, while the projected increase in average temperature may seem small in comparison to everyday experience, it is large in the context of past changes in the global climate. Over the time span of human civilization, decadal average surface temperature has varied by relatively small amounts, and these changes were generally quite slow and often only regional in extent; by contrast, the global average temperature rose by about 0.6°C over the 20th century and the increase was larger than this in some regions. The changes in climate and temperature over the next 100 years are likely to be several times larger than the changes in climate and temperature that took place between the last ice age (about 20,000 years ago) and the beginning of the 20th century. The warming is expected to be larger in the middle to high latitudes than in the tropics, larger over land areas than over oceans, and larger in winter than in summer (except in areas that are dried out by summer warming). Significant impacts on natural and managed ecosystems and on water resources are likely in many critical regions. While adaptation to such changes in one place or for one year may be possible, just as the US and Europe survived the heat of the 2006 summer, a multitude of changes simultaneously occurring around the world and persisting for decades (and longer) will create a very challenging situation.
The second reason for concern is the accelerating pace of change, because this acceleration increases the likelihood that various climate thresholds will be crossed before emissions are brought under control. If we could be assured that changes in climate and the associated impacts would occur only slowly and steadily, the potential would exist for orderly, gradual adaptation, even if this became expensive. The problem is that accelerating fossil fuel emissions increases the risk that changes will not be smooth, slow or always as we expect them to occur. Climatic history provides a number of indications that some types of changes can occur abruptly and suggests that 'tipping points' may exist that could lead to very large impacts occurring over years to decades, once thresholds are crossed or particular conditions arise.
The scientific objectives of this Summit were two-fold: first, to explore a number of these potential risks; and second, to evaluate the societal vulnerability, especially in the event of the changes occurring at an accelerated rate or in an abrupt manner. The policy-related objectives of this Summit were to explore the ability of society to deal with possible nonlinearities in environmental systems that could result in unexpectedly rapid rates of change in response to human-induced global warming, and to identify and encourage creative ways of reducing emissions, beginning now or in the very near term. These kinds of rapid, near-term emissions reductions are critical because without them, the risk of rapid and disruptive change increases sharply.
The sections of this book are organized around topics where science and experience are suggesting quite rapid change could occur — either negative changes resulting from sudden climate impacts, or positive changes from effective adaptation or mitigation efforts. Thus, the sections of this book, each starting out with a brief overview from the chair of that session of the Summit, cover the following areas:
Part 1 focuses on the pace of climate change. Scientific studies over the past 25 years have made clear that the responsiveness of the global climate to higher concentrations of CO2 and other greenhouse gases is unlikely to be less than the lower bound of what has been incorporated into the IPCC's estimates, but could well be greater than the upper bound that has been used. Recognizing that much warmer climates have existed in the Earth's distant past, the three chapters (1-3) in this section explore the risk that climate change and its direct health impacts on society will be greater than is generally perceived.
Part 2 focuses on factors that affect the pace of sea level rise. Global sea level is estimated to have risen almost 0.2 m during the 20th century, and recent satellite records suggest that the rate of rise has increased to over 0.3 m per century, presumably as a result of more rapid ocean warming (causing greater thermal expansion) and accelerated melting of mountain glaciers and the edges of the Greenland Ice Sheet. The recent collapse of the Larsen-B ice shelf, and the consequent acceleration of glacial streams that the ice shelf was buttressing, suggest that the loss of grounded ice can occur much faster than has traditionally been assumed. With the Greenland and West Antarctic ice sheets each containing the equivalent of about 6 m (20 feet) of sea level rise, the three chapters (4—6) in this section explore the potential for warming to prompt accelerating changes in the Earth's cryosphere.
Part 3 focuses on the increasing potential for damaging impacts in coastal regions. Coastal wetlands, marshes and estuaries are the breeding grounds and hatcheries for a vast array of marine and terrestrial species, some of which are located there throughout the year, but many of which migrate through in their seasonal pursuit of food and habitats for their young. These regions are vital to the health of the global ecosystem and provide important food and resources for society. Proximity to the resources of both the land and the ocean has led to many of the world's largest cities being located on the coast, often serving as ports, transportation hubs, and centers of trade and commerce. In addition, because the coast is aesthetically attractive, permanent and vacation communities now cover the barrier islands and coastal bluffs in many regions of the world, accepting the risk and damage that comes from existing levels and intensities of storms and storm surges. Climate change, however, will create new stresses, including more powerful tropical cyclones, higher sea levels and higher storm surges. The five chapters (7—11) in this section explore the risk of increasing damage and the steps that may be possible to limit the most severe impacts.
Part 4 focuses on the pace of ecosystem transformation. From southeastern and northeastern forests to the grasslands of the Great Plains and deserts of the southwest, the climate determines the prevailing ecosystem and, to a large extent, the potential for agriculture. As the climate changes, it is often suggested that existing systems will slowly move or seamlessly evolve into new systems with no disruption in the services the ecosystems provide. However, increasing evidence is emerging that pests, disease and fire accelerate the changeover from one system to another. With evidence indicating that the loss of ecosystems, or at least their key species, can occur much more rapidly than their reestablishment, the three chapters (12-14) in this section explore the potential for rapid changes in ecosystems to significantly disrupt biological diversity and the other ecosystem services that society depends on.
Part 5 focuses on the potential for accelerating action to limit climate change. Recognizing that climate change is underway and has the potential to cause damaging impacts for generations into the future, a growing number of efforts are underway to limit its pace. The early enthusiasm for dealing with the climate change issue that led to negotiation of the UN Framework Convention on Climate Change in 1992 and international acceptance of the need to limit 'anthropogenic interference with the climate system' has been replaced by an international process that is struggling to take steps so limited that continuing on this path is likely to produce at least dangerous, and quite possibly catastrophic, consequences. Recognizing this, a distributed and, in many cases, bottom-up effort has started with the intent of saving the world by changing it. The nine chapters (15-23) in this section describe a number of very positive efforts that are getting underway to slow the pace of climate change, proving that the Earth's climate can be stabilized because change is not only possible, but is justified, necessary, and, in many cases, cost effective.
Those who participated in the Summit came away enthusiastic and excited about what could be done, and committed to making changes happen through their efforts and through their collaborations and participation with the many other organizations and efforts of which they were and are a part. It was their enthusiasm and requests that led us to assemble the perspectives offered at the Summit into this book. We hope that the following collection of articles, which cover topics across the spectrum of climate science, environmental and societal impacts, and actions and programs to limit emissions, will inspire others to join the effort to limit climate change and do what needs to be done.
Already the Summit has begun to bear fruit in both Latin America and in small island nations. Just as the Summit opened, the Director General of Mexico's National Instituto Nacional de Astrofisica, Optica y Electronica (INAOE) wrote to the Climate Institute inviting it to join in building a High Altitude Climate Observatory in Pico De Orizaba National Park near the Large Millimeter Telescope operated by INAOE. Led by the efforts of Luis Roberto Acosta of the Climate Institute, plans and funding have solidified for this effort, and construction is expected to begin in the summer of 2007 with the High Altitude Climate Center operational by mid-2008. Co-location of the climate observatory and the radio telescope greatly increased interest in climate change in the Mexican news media. The Climate Institute's office in Mexico City is now working closely with the environmental awareness group, CICEANA (Centro de Información y Comunicación Ambiental de Norte América), to launch a national climate awareness campaign focused on actions that individuals can take to reduce energy use and greenhouse emissions. Wal-Mart, which has 2.6 million daily customers in Mexico, has indicated its willingness to disseminate public service messages on internal store video systems, and Televisa, Mexico's largest television network, has agreed to incorporate these public service messages into its programming. Two major museums in Mexico City are also now working with the Climate Institute to develop exhibits that will communicate the urgency and importance of climate change and practical steps individuals and society can take to respond to it.
This effort extends well past consciousness-raising to encompass practical steps in scientific cooperation, anticipatory adaptation, building design and siting, and energy use and design. The International Leadership Alliance for Climate Stabilization, the public—private partnership announced at the Washington Summit, is working to set up a flexible framework for North—South cooperation in creatively adapting to climate change and reducing greenhouse gas emissions. Already the Dominican Republic and Mexico's State of Quintana Roo appear eager to participate in the Leadership Alliance. Iceland, the Government of Mexico City and several English-speaking small island nations in the Caribbean appear interested in similar cooperative endeavors. Among the possible areas of cooperation would be an island-to-island initiative in which smaller island nations could learn from the success of Iceland in geothermal and hydropower development and the promising beginnings of the Dominican Republic in bioenergy, adaptation of the state-of-the-art storm surge mapping developed by the International Hurricane Research Center in Miami for use in vulnerable island nations or states such as Quintana Roo, use of vetiver grass to preserve beaches and roads from erosion and destruction in severe storms, and development of building practices to optimize energy use and survivability. A key to success in both adaptation and greenhouse emissions reduction is thinking smart from the outset. Some of these measures may in fact provide not only sizable reductions in greenhouse gas emissions, but also yield cost savings to industry and consumers.
The success of the Summit was built on the efforts of many people, to all of whom we offer our sincere thanks. These include the speakers and session chairs, whose names are indicated in the Table of Contents and whose brief biographies appear in an appendix, those who came and participated in the very lively discussions in and around the conference, those who helped to fund the Summit and its related events, and especially those individuals who helped to organize the conference. Details on many of these individuals and institutions are provided in the Acknowledgements section in the appendices.
For 20 years, the Climate Institute has sought to increase awareness of the climate change issue and to propose and encourage positive approaches to addressing it — ways around which we can all come together to treasure the world that we have and to create a society that lives more sustainably. The Climate Institute will be continuing these efforts over coming decades, and we invite everyone to join in - check for information about our ongoing activities at www.climate.org.
The Potential for Rapid Changes to the Weather and Climate
Was this article helpful?
Your Alternative Fuel Solution for Saving Money, Reducing Oil Dependency, and Helping the Planet. Ethanol is an alternative to gasoline. The use of ethanol has been demonstrated to reduce greenhouse emissions slightly as compared to gasoline. Through this ebook, you are going to learn what you will need to know why choosing an alternative fuel may benefit you and your future.