Published December 12. 2011 4:00AM
Weather is always a topic that people like to talk about, and 2011 is certainly providing plenty of fodder. Not only has the country suffered a dozen billion-dollar-or-more weather disasters this year, but Wednesday's drencher in the state made 2011 the wettest year in Connecticut in 106 years of record keeping.
Climate variability is not the sole reason for these shattered records. At some point, disbelievers are going to have to acknowledge that human activity is playing a role in global warming and our changing weather.
Connecticut has received 66.91 inches of rain this year, a figure that includes the melted liquid equivalent of snow. The state got walloped by a tough, snowy winter, Tropical Storm Irene in August and the unprecedented snowstorm in late October. Nationwide, tornadoes, droughts, heat waves, wildfires in tinder-dry forests, hurricanes, blizzards and flooding have killed hundreds and resulted in $52 billion in damages.
Warming global temperatures are altering traditional weather patterns, making it warmer and dryer in some places and, counterintuitively, sometimes colder and snowier than normal in others.
While the National Oceanic and Atmospheric Administration said increased populations and development in flood-prone areas has contributed to the monetary losses linked to weather-related calamities, it noted "there is evidence that climate change may affect the frequency of certain extreme weather events."
Some of that evidence comes in a paper recently published in Nature Geoscience, authored by two Swiss climate modelers, that states that at least 74 percent of the Earth's warming is a result of human activity.
A story on the study in Scientific American reports that since 1950, the average global surface air temperature has increased by more than 0.5 degree Celsius, or nearly 1 degree Fahrenheit. While it may not sound like much, on a global scale it results in significant changes to Earth's climate.
To separate human and natural causes of warming, the Swiss team analyzed changes in the balance of heat energy entering and leaving Earth - a new "attribution" method for understanding the physical causes of climate change.
Their findings, which Scientific American said are strikingly similar to results produced by other attribution methods, provide an alternate line of evidence that greenhouse gases, and in particular carbon dioxide, are by far the main cause of recent global warming.
The report will surely not end the debate over the cause of extreme and severe weather - the most expensive disaster in U.S. history, Hurricane Katrina in 2005, caused 1,800 deaths and $145 billion in damages - but it can help to guide the discussion. There is a reason for what is happening. To some degree at least, global warming is contributing to an increase in freak storms that are pummeling people and property and those changes are due in large measure to human behavior.
Critics will dispute that, but the science says otherwise. Policy on a global scale should aim toward reductions in greenhouse gas production. To do otherwise invites greater disasters to come.