An editorial by professors Cameron Wake of the Climate Change Research Center (CCRC) and Barry Rock of the Complex Systems Research Center (CSRC) published in the Februrary 6, 2004 edition of the Union Leader. |
Science shows winters in New England are shrinking
By DR. CAMERON WAKE and DR. BARRY ROCK
SOLID SCIENCE is built upon solid data. When it comes to nailing down the workings of New England weather, the only sure thing is that it varies from day to day and from region to region. As Mark Twain said in 1876, "One of the brightest gems in the New England weather is the dazzling uncertainly of it."
Because of this, the best way to accurately document regional climate change is to look at broad regions over long periods of time rather than day-to-day or year-to-year changes in one area. Pat Michaels, in a recent column in The Union Leader, chose instead to focus on an isolated piece of data to dismiss evidence of regional climate change. If he had looked at the broader collection of data from New England he would have seen a very different picture than the one he presents.
Science, in fact, shows that New England has been warming over the past 100 years, especially during winter months.
Detailed analysis of instrumental temperature records from 56 stations in the northeastern United States indicates that the average annual temperature has increased by 1.8 degrees Fahrenheit in the last century. Moreover, the 1990s were the warmest decade on record both globally and in the northeast United States. Average winter temperatures (December to February) for the Northeast have increased 2.9 degrees in the last century.
Wintertime lake ice also reflects this warming trend. Rather than look at a single lake, as Michaels does, we have analyzed data from many lakes in northern New England. For example, the average ice-out date on Lake Winnipesaukee occurs eight days earlier today than it did in the late 1800s. In recent decades, Sebago Lake in southern Maine has had a decrease of 14 days in the length of time it is covered with ice each year. Today, Lake Champlain freezes over an average of eight days later than in did 100 years ago. Even more remarkable is the fact that between 1815 and 1950, the lake failed to freeze over completely only six times, while since 1950 it has failed to freeze over 25 times.
Other data are clearly indicative of the warming trend we are experiencing. Over the last century, growing seasons across the region have gotten longer by an average of nine days. Sea surface temperatures from the Gulf of Maine and off the Connecticut coast have warmed by at least 8 percent, with springtime warming almost 20 percent. Maple sap flow, a process that requires freezing nights and above freezing days, is occurring earlier in the winter months, and lilacs across the region are blooming earlier.
After analysis of the best climate science, the Intergovernmental Panel on Climate Change, an international body consisting of hundreds of scientists, and the United States National Research Council?s Committee on the Science of Climate Change concluded that the warming that has occurred over the last 30 years is most likely due to the increase in heat-trapping gases resulting from human activities, primarily the burning of fossil fuels.
Pat Michaels would have us just stick our heads in the sand and hope the global warming problem goes away. However, the data are clear. The climate of New England is warming up and we are going to have to deal with its consequences. In the meantime, voters would be well advised to stay attuned to the fact that Pat Michaels is only reporting data that supports his viewpoint, not the data that reflects broad scale climate trends in New England.