“There has been a series of extreme weather incidents. That is not a political statement but a factual statement. Anyone who says there’s not a dramatic change in weather patterns, I think, is denying reality, and I would like to say this is probably the last occurrence of this type of event we will have. But I don’t believe that. … We have a 100-year flood every two years now. … We have a new reality when it comes to these weather patterns.”
New York Gov. Andrew Cuomo, Oct. 30, 2012
After years of climate change being a minor issue, Hurricane Sandy has elevated this issue to the front page. As Cuomo notes, we now live in a world with a changed climate. Sandy is no longer an aberration but part of the new normal. Sandy’s devastating impact will likely prove to be the most expensive storm ever (estimates already exceed $50 billion). Regardless of what we do to reduce carbon dioxide emissions over the next decades, the disruption of weather will continue to accelerate over the next 100 years and beyond.
How did climate change contribute to the devastation caused by Hurricane Sandy? First, all weather events are affected by climate change because the context in which they occur is on an increasingly warmer and wetter planet. What are some of the climate-related factors that contributed to the ferocity of Sandy? The increasing temperatures in the oceans cause thermal expansion of the water, which contributes to sea level rise. There are also changes in circulation patterns of the North Atlantic Ocean that increase sea level even more along our part of the coastline, about four times greater than the global average. Therefore, storm surges occur on top of an already higher sea level. In the case of Sandy, there was also an astronomical high tide — which is not related to climate change — that further exacerbated the situation.
When sea surface temperatures are higher, more water vapor enters the atmosphere, which increases rainfall. The greater energy from higher temperatures and water vapor make storms bigger and more intense. September had the second-highest global ocean temperatures on record. In our case, ocean temperatures along Sandy’s track were higher than usual, about 5 degrees Fahrenheit above normal. This helped to sustain Sandy as a hurricane along her entire track to the New Jersey coastline. There was even a substantial bump upward in her strength (with winds going from 75 to 90 mph) when she took a left turn and crossed the even warmer Gulf Stream.
Sandy’s unusual track was caused by a very strong blocking high-pressure system over Greenland, a highly negative North Atlantic Oscillation. Such blocking highs have been unusual in the fall, occurring about 2 percent of the time in the past record, but these blocking events have increased in recent years, and this has been linked to the warming climate (especially strong in the Arctic). The jet stream pattern was also very unusual, and these kinds of patterns have recently been linked to a decline in the Arctic sea ice. The lowest amount of sea ice ever observed was seen this summer. These aspects are new discoveries and still in the speculative realm. Much additional research is needed to link ocean and atmosphere circulation patterns.
Climate scientists have been warning about the increase in these devastating events on a warming planet for many years. Our planet is already locked into a lot more warming owing to the increasing carbon dioxide levels during this century and beyond, likely 7 degrees Fahrenheit (4 degrees Celsius) or more by 2100. Sea levels will certainly continue to rise, and changes in oceanic and atmospheric circulation patterns will certainly continue to occur. Alarmingly, scientists’ worst-case scenarios are already occurring. We must pay a lot more attention to these warnings and support the work that informs the models that allow us to predict with a higher degree of certainty what our future world will look like. We must all do what we can to reduce anthropogenic emissions of carbon dioxide and other greenhouse gases.
Will “superstorms” such as Sandy happen again? Yes. The question is what will be the frequency of such extreme events? The climate continues to warm, with all of its consequences also increasing in scope: heavier precipitation, flash flooding, increased hurricane activity, heat waves, droughts and wildfires. Sandy was unusual in almost all respects — the term ‘unprecedented’ was used very frequently. Unfortunately, such massive storms are predicted to become the new normal.
What does this mean for higher education? As one of his first acts, Drexel University President John A. Fry signed the American College and University Presidents’ Climate Commitment. A critical part of this document obligates Drexel to exercise leadership on the climate issue. The specific wording of the pledge states:
“We believe colleges and universities must exercise leadership in their communities and throughout society by modeling ways to minimize global warming emissions and by providing the knowledge and the educated graduates to achieve climate neutrality. Campuses that address the climate challenge by reducing global warming emissions and by integrating sustainability into their curriculum will better serve their students and meet their social mandate to help create a thriving, ethical and civil society. These colleges and universities will be providing students with the knowledge and skills needed to address the critical, systemic challenges faced by the world in this new century and enable them to benefit from the economic opportunities that will arise as a result of solutions they develop.”
This ambitious commitment needs to be met. It is clear to us that students need to be educated to address the climate change issue across the curriculum. This involves devising ways to minimize and eventually eliminate carbon dioxide emissions. At the same time, we need to develop means to adapt to the new normal of a warming planet. Under President Fry’s leadership, the environmental science and policy programs are now engaged in a rebuilding effort after 10 years of neglect. President Fry’s environmental initiative provides an opportunity to fully meet this commitment by engaging in a thorough, impartial and transparent evaluation of our environmental programs and how they address climate change through a joint partnership between the administration and faculty who are actively engaged in research and teaching in this area. We need to engage in a rebuilding of these critical academic programs. This is what Drexel has committed itself to and what it owes its students.
Susan S. Kilham is a professor of environmental science in the Department of Biodiversity, Earth and Environmental Science.
Robert Brulle is a professor of sociology and environmental policy in the Department of Culture and Communication, and is presently on sabbatical leave as a fellow at the Center for Advanced Study in the Behavioral Sciences at Stanford University. They can be reached at [email protected].