By Mary Kuhlman Indiana News Service
---- — INDIANAPOLIS - Indiana and other parts of the nation may be frozen, but an expert says the world is still warming.
Lonnie Thompson, an Ohio State University professor who has studied the effects of climate on glaciers around the globe, said public opinion on climate change tends to shift in response to cold weather patterns.
“We have a tendency to say, ‘Well, if it’s cold here; the world must be getting colder.’ Well, this is not true,” he said. “We live on a huge planet. It’s a complex system, and that natural variability that’s always been with us continues, even though the longer-term trend is toward warming.”
Weather is what is currently happening, Thompson said, while climate figures are averages based on the weather. While the world does go through ice ages and warming periods, he said, it’s the longer-term rate of change that is prompting alarm about the earth’s warming pattern.
Each of the past three decades has been hotter than the one before, Thompson said, and those three decades were hotter than at any time in the previous 1,400 years.
In his travels, Thompson has studied glaciers, tree rings, corals and other bio-records to find the natural indicators of climate change. Scientific data tells the same story, he said.
“If you look at the instrumental records, eight of the nine warmest years in that 132-year record have occurred since 2000,” he said. “So, the world hasn’t stopped warming - it just happens to be cold right now here in Ohio.”
The current frigid temperatures, as well as other so-called “extreme weather events,” could be connected to climate change, he said, adding that some scientists think it’s through a chain reaction starting with the warming of the Arctic.
“A number of papers have been published suggesting that the loss of sea ice in the Arctic has caused larger undulations in our jet stream,” he said, “which allows the Arctic air masses to penetrate farther to the south, and also warm air to move farther to the north.”
When considering the changing climate, he said, it’s important to look at what’s happening on a global scale. While it may have been 15 below zero in Indianapolis on Monday, it was 34 degrees Fahrenheit in Anchorage, Alaska.