The State of Global Climate Change in Maine 2004

Brendan J. Carroll

 

Global Climate Change: The Issue in Context

Introduction

Global climate change, popularly known as “global warming,” has the potential to greatly impact the natural environment and human society in many significant ways. In the last two hundred years, both global temperatures and atmospheric concentrations of greenhouse gases have accelerated, compared to rates observed on a geologic timeframe10-12. While a growing body of scientific consensus has determined that changes in the climate system are unmistakably human in origin, a great deal of uncertainty still exists as to the extent of future changes and impacts. The high profile of the science and its dire implications have caught the attention of policymakers the world over. An international strategy to address the issue has been in the works for over ten years, although the perceived high costs of policy changes have stalled these efforts. Still, governments at all levels, businesses, and other organizations around the world have enacted substantive climate policies.

            The basic science behind global climate change involves many complex interactions among the chemicals and energy of the sun, the earth, and its atmosphere10-14. Solar radiation travels towards the earth, some is reflected immediately upon reaching the atmosphere, and the remainder passes through. This energy is then absorbed into the climate system – by the oceans, land, and biota, which re-emit the energy. Some of this passes through the atmosphere but some is absorbed by the atmosphere. Since more energy penetrates the atmosphere than passes out of the atmosphere, a natural “greenhouse effect” heats the earth. The gases in the earth’s atmosphere that trap this energy are known as greenhouse gases, and include water vapor, carbon dioxide, methane, nitrous oxides, and several chemically complex gases. Without this natural greenhouse effect, the earth would be at least 33˚C cooler.

While this natural greenhouse effect is necessary for life on earth as we know it today, a growing consensus among scientists has shown that human activities since the industrial revolution have resulted in an increased greenhouse effect10-14. An international body of climate experts, the Intergovernmental Panel on Climate Change (IPCC), has synthesized this consensus into three scientific assessment reports, each with more detailed and certain conclusions and predictions10-12. According to the IPCC, human activities emit greenhouse gases that have raised atmospheric concentrations of carbon dioxide by 31 percent over the 20th century. While concentrations of other greenhouse gases have changed as well, carbon dioxide stays in the atmosphere for tens to hundreds of years, thus impacting the climate system long after its associated human activity has emitted the gas. This increased greenhouse effect has led to a rise of 0.6ْC in the global mean temperature in the 20th century. The increase has not been evenly distributed around the world. The latest scientific assessment report has indicated that this relatively rapid change in the climate system is caused by greenhouse gases released from human activities, and all major scientific studies and reviews have validated this point11,13,14.

            Predicting the future is no easy task for any scientific assessment. The large amount of uncertainty regarding feedback effects, nonlinearity, complex interactions, and human societal changes make predicting future scenarios for human-induced climate change particularly problematic11,13,14. The IPCC predicts a further rise in mean temperature between 1.4 and 5.8˚C. While the estimates and predictions of the IPCC are accepted by the vast majority of climate scientists, a small but vocal minority of climate skeptics present different models for the future, based on different scenarios for growth in emissions and the notion of a robust rather than fragile world15,16.

            The impacts from this changing climate are likely to be very severe and widespread, impacting virtually all human and natural systems, according to the IPCC and other scientific reviews13,14,17,18. Higher average temperatures that expand the volume of the world’s oceans along with melting polar ice will accelerate natural sea level rise. The IPCC predicts a sea level rise of between 0.09 and 0.88 meters by the end of the next century. Low-lying islands and coastal countries, as well as coastal communities, are particularly at risk from higher sea levels. Millions of people likely will be displaced by the end of the next century18. Other significant impacts of a changing global climate are likely to include droughts, increased frequency and severity of weather events, and extinction or migration for many vulnerable species18-21. Fears of abrupt climate change, resulting from such possible events as a breakdown in the North Atlantic Oscillation, a sea temperature and salinity dependent system that determines weather in the North Atlantic, have aroused the attention of scientists outside of the IPCC14,22.

            Growth in human activities such as transportation and consumption, as well as growth in human population will determine how much climate will change11,13,14. The IPCC estimates that three quarters of anthropogenic emissions of greenhouse gases stem from fossil fuel combustion. The burning of fossil fuels to create energy to power our cars, appliances, machines, and virtually everything that runs on electricity has become a necessary part of the modern life. This is particularly true for the United States, the single largest emitter of greenhouse gases, whose carbon dioxide emissions account for twenty-five percent of the world’s total23. If fossil fuel consumption continues to rise, climate change will continue to accelerate. Consequently, any policy designed to seriously limit future impacts on the global climate system will involve changes in the way society generates energy24,25. Such policies will require shifts toward renewable energy sources in addition to reductions in energy use.

            The transportation sector is one of the largest and fastest growing sources of greenhouse gas emissions worldwide. The sector accounts for 20 percent of the world’s carbon dioxide emissions, and a large share of its emissions of nitrous oxides and other greenhouse gases26. Light truck and automobile transportation accounts for 50 percent of all transportation emissions26. Since the oil crisis of the 1970s, considerable fuel efficiency gains have led to reductions in emissions of carbon dioxide per vehicle, but these improvements have not kept up with rapid growth in vehicle transport. In only fifty years, the global fleet increased from 46 million vehicles at the end of World War II to 641 million in 199626. US total and per capita fuel consumption from transportation exceeds that of any other nation, as total travel activity in the US is larger than other nations, and US vehicles are much more fuel intensive27. Consequently, many local, national, and international policies aimed at reducing greenhouse gas emissions focus on the transportation sector.

Historical Context

            Scientists associate rising carbon dioxide and other greenhouse gas emissions with changes in human activities over the past two-hundred years11. Since the industrial revolution of the late 18th century, humans have generated millions of tons of carbon dioxide through combustion of fossil fuels. Since then, technology has allowed greater productivity and higher living standards for the countries that industrialized rapidly. This revolution required coal, oil, and other carbon-intensive inputs to fuel production. As a result, atmospheric concentrations of greenhouse gases have increased18.

 

Recent Issues

The increasing awareness by scientists and policymakers of climate change as a serious issue has generated an international dialogue aimed at mitigating this threat to our climatic system26,28-30. In 1992, heads of state and environmental ministers from around the world gathered at an environmental summit in Rio de Janeiro, Brazil, drafting the first international treaty aimed at addressing the threat of global climate change31. The United Nations Framework Convention on Climate Change (UNFCCC), ratified by virtually all nations, became the framework through which further policy dialogues would take place. A major component of this framework treaty required that all parties to the convention submit national inventories of emissions. The framework set a goal of reducing emissions to a level that would not be harmful for future generations, but did not set a timetable and so this goal has neither been met nor even credibly attempted by policy measures in most countries28,29.

            Five years later the parties to the Convention met in Kyoto, Japan to draft a Protocol to the convention that would set emissions targets and timetables32. They set a goal to reduce world greenhouse gas emissions by 8 percent from 1990 levels, by the first commitment period of 2008 to 2012, to be shared among all countries that ratified the treaty. For some countries, particularly the former communist states of Eastern Europe, this meant an increase in emissions, as emissions there have decreased significantly since 1990. For others, such as the United States, this meant a substantial decrease in emissions. Legislators and policymakers in the US deemed this too costly for the US economy, and so the US has refused to ratify the treaty33. Some contend a new approach to international climate agreements is necessary to lead to a stabilization of atmospheric greenhouse gas concentrations through inclusion of the US34-36.

With ratification by Russia, the Kyoto Protocol will go into effect in February of 2005, binding countries representing only 62 percent of the world’s total emissions to emissions reductions in the next ten years37. Developing countries were exempt from reductions in this round of negotiations in order to promote economic development, despite their growing share of the world’s emissions. As a result, rising emissions in both the US and developing countries will undermine the success of the Kyoto Protocol in achieving its goal of lowering atmospheric concentrations of greenhouse gases.

            The US has remained a part of the Kyoto process only as an observer since 2002. The predicted costs to the US economy were judged by the federal government as too high to offset the benefits38. Other analysts argue that these benefits (i.e., the future costs of inaction) were underestimated, and the costs were not easily understood, and hence overestimated33. Since then, climate change policy has taken a more voluntary form in the US39,40. Businesses have engaged in voluntary emissions trading schemes to reduce their emissions, with tax credits and other incentives provided by the federal government39.

At the regional, state, and local levels, innovative voluntary initiatives have set targets and policies for reducing emissions41,42. Twenty-eight states and Puerto Rico have created policies to reduce emissions in sectors over which these states have significant authority, including taxation, land-use, utilities, and transportation40. Some of these efforts comprehensively address climate change, as exemplified by the Climate Action Plans of Maine and Connecticut. Other initiatives, such as the California auto emissions standards, are more narrowly focused. Many initiatives will have additional benefits, including cleaner air and lower energy costs40. Although still in their infancy, if these initiatives are carried out to their targets, many greenhouse gas producing activities in the US will be under emissions limitations.

 

Global Climate Change: The Issue in Maine

Introduction

Global climate change will leave no area unchanged. In Maine, where so much identity and so many livelihoods are strongly tied to the natural world, this global issue has already impacted human and natural systems. Recent estimates of future climate change predict even more visible and devastating effects on the state43. Early recognition of the need to address this problem has generated a noteworthy local policy response to a problem of global origins. While Maine cannot single handedly prevent further degradation of its environment by climate change, lessons from its groundbreaking approach can inform policymakers everywhere.

Maine’s traditional ties to its coasts, weather, and wildlife make its people vulnerable to stresses in the natural world. Current computer simulation models used to predict future climatic changes cannot easily predict impacts at such small scale as Maine itself or even New England. However, from what broad changes scientists can estimate from larger scale models, many predicted changes will have spillover effects on Maine’s economy and identity44. Many of these changes will be both costly and irreversible.

            Maine’s most noteworthy geographic feature, its coastline of 3,000 miles, traces a line through many of the state’s communities, is responsible for millions of dollars of Maine’s economy, and provides immeasurable symbolic value to the state. Thermal expansion of the world’s oceans, resulting from rising sea temperatures, coupled with melting polar ice caps, are predicted to raise sea levels significantly by the end of this century18. People who live along Maine’s coastline will witness the encroachment of the sea on their communities. Although scientists have been unable to predict the exact extent of this sea level rise, the EPA estimates that a 14-inch rise in Rockland and a 19-inch rise in Portland are both likely by the end of this century43,45. The increased frequency and severity of storm events will magnify the effects of a rising sea, as flooding and storm surges will be more frequent and devastating. Although seaside communities will have a limited ability to adapt to these conditions, vulnerable coastal wetlands will face even greater difficulty in surviving. In the Casco and Saco Bay areas, 10 to 20 percent of local wetlands are likely to be lost under widely accepted scenarios46.

            The cost of sea level rise to these coastal communities is significant. A 20-inch rise, well within scientists’ estimates for the next century, would flood 80 acres of land in Old Orchard Beach, where out-of-state tourists and Maine resident vacationers inject money into the local economy every summer46. In some areas, where expensive beachfront property already clings precipitously to the land, coastal erosion and storm surges may plunge hundreds of homes into the rising sea in the next hundred years. The cost of insuring coastal property has doubled since the 1970s; one study estimates that 286 million dollars of Maine’s insurance costs in the 1990s were weather-related47. In addition to residential areas, public infrastructure such as sewage treatment plants and underground storage tanks are also at risk from flooding.

            Further inland, changes in the nature and timing of Maine’s weather will impact natural systems throughout the state. Although scientists have been unable to predict with certainty future changes in the amount of precipitation the state receives, a recent study by the US Geological Survey (USGS) has shown evidence that over the past century, Maine’s precipitation has turned increasingly from snow to rain43,44,48. Throughout the past century, the ice-out dates for many rivers and lakes throughout the state have occurred earlier and earlier in the season, and river ice thickness has been decreasing49,50. Additional, unpredicted changes are also likely to occur.

 

Historical Context

Fossil fuel combustion, and hence carbon dioxide emissions, became a part of Maine’s economy more slowly than in the rest of New England. Traditionally, and still to a greater extent than anywhere else in New England, water has provided Maine’s power. When steam power generated from oil or coal reached the industrial cities of southern New England in the 1820s, the high cost of transporting the fuel to Maine and Maine’s abundant water power kept fossil fuel power from Maine for decades51. These sources of power became more widely used when electricity came to Maine in 188051.

            On the other hand, fossil fuel use in the transportation sector has played a major role in Maine since the first steam-powered railroads laid their tracks in the 1830s52. By 1912, over 2,000 miles of track crisscrossed the state, carrying passengers and cargo from York to Aroostook52. The railroad gave way to the automobile in the early 20th century. The opening of the Maine Turnpike, from Kittery to Portland in 1947 and then to Augusta in 1955 spurred rapid growth in automobile use in Maine53