The May/June issue of Weatherwise, our annual Almanac, gives us a chance to look back at the previous year of weather across the United States and the rest of the world. While the information contained within is fascinating in its own right, it also provides us with a chance to compare recent weather with previous years to see how the climate might be changing. We try to show how each year's events compare to previous years.
Heat, drought, and Superstorm Sandy headlined 2012. The warmest year on record in the United States featured one of the most extreme summer heat waves, the warmest spring in over a century, the most extensive drought in more than half a century, and the second most expensive cyclone of all time. In Europe, some of the most extreme wintry weather of the past several decades bore down early in the year and was then followed by extreme heat and dryness in the spring and summer. Hurricanes Isaac and Sandy left a trail of destruction in the Caribbean, while a number of land-falling typhoons created havoc in the western Pacific.
Such extreme weather events seem to point to a climate that is getting more dramatic and creating more violent storms. Yet other data are less clear. For example, 2012 was far less active for tornado activity than the record-breaking 2011. In 2012, there were 936 tornadoes, which is just 82 percent of normal. Meanwhile, there was an average amount of tropical cyclone activity during the 2012 eastern North Pacific hurricane season, with few landfalls and little damage.
So what to think? Is climate change resulting in more extreme weather? As usual, the answer is not cut and dried, and we cannot jump to any conclusions based on one year alone. But that is the beauty of the annual Weatherwise Almanac. We catalogue the weather each year so that comparisons and contrasts can be made.
I hope you enjoy—and learn a lot from—this edition of the Weatherwise Almanac. As always, we welcome feedback from our readers and would love to hear your thoughts on how the weather has changed through the years and the pages of the magazine.