At a time when many consider climate change to be one of the most pressing challenges facing the world’s population, it remains unclear which course of action will do the most good for the planet and its inhabitants. Michael Greenstone, the 3M Professor of Environmental Economics at the Massachusetts Institute of Technology, and director of the Hamilton Project, discussed this issue during a lecture from The Sustainability Program of the Arthur Levitt Public Affairs Center.
Greenstone’s talk, “Is Adaptation the Only Solution to Climate Change?” attracted many interested in economics as well as the environment. Greenstone served as the chief economist for President Obama’s Council of Economic Advisors in the first year of his administration. He also served as an editor of The Review of Economics and Statistics and as a member of the EPA Science Advisory Board’s Environmental Economics Advisory Committee.
Greenstone’s research and involvement in issues of climate change lead him to believe that, out of the possible approaches that we have developed to address climate change, adaptation appears to be the most inevitable. He demonstrated this conclusion through a series of seven “observations about climate change,” which provided a brief outline of where the planet stands in relation to this issue at the moment, both politically and environmentally.
Greenstone’s first observation is that “climate change is projected to alter the environment in dramatic ways.” The most obvious of these alterations is rising mean annual global temperatures, a trend which has been documented extensively in recent years and is expected to continue rising.
According to Greenstone, the mean annual global temperature is projected to rise 18 percent between 2000 and 2100. This could mean a drastic increase in the average annual number of days a U.S. resident can expect to experience temperatures over 90 degrees Fahrenheit. Currently, U.S. residents experience relatively few days of such high temperatures each year on average, though this could increase to approximately 40 days at the current rate of change. Such temperatures could have negative repercussions for mortality rates and agriculture around the world.
Greenstone's second observation is “the potential costs of climate change are substantial.” Some countries or areas may stand to gain from climate change, while other areas stand to lose. Potential losses include increased water stress, a greater number of extinct animal species, and stronger storms. Overall, the losses are expected to outweigh any potential benefits.
With the first two observations in mind, Greenstone’s third observation states that there are four known climate changes policy categories used internationally to address climate change. The first of these is funding of basic research and development, which involves research to lower the high costs of alternative fuels or to develop new forms of fuel. However, this policy type is problematic because it is difficult to achieve from a political standpoint.
The second policy type is geo-engineering, which would attempt to physically lower the earth’s temperature by adding certain chemicals into the atmosphere. According to Greenstone, this method is still not developed enough to know the full consequences of altering the atmosphere. Furthermore, different countries would have varied interests in what average temperatures the earth should be kept at, which introduces further political complexity.
The third possible approach to climate change policy is mitigation, or lowering total usage of the highest carbon-releasing fuels, though this too has not been embraced by the developed world anywhere but in the EU. As Greenstone explains, developing countries have the fastest-growing fuel consumption of any group of nations, and so those countries will be most hesitant to mitigate fuel usage.
This leaves the fourth policy type, adaptation, which requires humans to find innovative strategies to cope with the inevitabilities of climate change, such as higher temperatures, in new ways. However, the difficulty with this method is lack of research.
The fifth and sixth observations of the presentation had to do with the role of developing countries in causing, and stopping, climate change. For these countries, a significant reduction in energy consumption could lead to huge losses in overall growth. For example, China could stand to lose trillions of dollars if it were to significantly cut its energy consumption. Examples such as this tie into the seventh observation, which states that there are many practical issues regarding reaching global consensus on climate change.
For all these reasons, Greenstone finds adaptation to be not just necessary, but in fact the only course of action that is bound to happen. He went on to describe the effects that climate change can have on developing countries, contrasting the U.S. with India as an illustration. In the U.S., there is a negligible percent change in mortality rates for each additional day above the average of temperatures higher than 90 degrees. But in India, each additional very hot day corresponds with a .05% decrease in agricultural output and a 1 percent increase in the mortality rate. For those whose incomes depend strongly on agriculture, these changes can be devastating. By the end of the century, climate change may be responsible for a 3 percent mortality increase in the U.S., but a 46 percent increase in the mortality rate in India.
In the U.S., many people deal with very hot days by using air conditioners and other electric tools. Greenstone hopes that, through adaptation, we might be able to improve prospects for people around the world using a similar approach, though without such high costs to the environment. He believes that if enough research is put into developing an adaptation plan that can work for all countries cheaply, future lives can be saved.