Scientist Ted Scott observed significant changes in summer conditions in Minnesota due to climate change. In collaboration with researchers from the University of British Columbia, he studied how summer has transformed in 10 cities worldwide, finding that summer conditions are now arriving earlier, lasting longer, and feeling more intense due to anthropogenic global warming.
The study, published in Environment Research Letters, revealed that the length of summer has increased by an average of six days every decade globally, with Minneapolis experiencing a nine-day increase and Sydney seeing a dramatic fifteen-day increase. Scott noted his childhood summers in Minnesota felt different, with seasons changing more rapidly and feeling more intense.
The researchers analyzed historical temperature data to establish a threshold for what constitutes summer in each city. For instance, Sydney’s summer, once starting on January 6 and ending on March 9 in the 1960s, has shifted to starting almost a month earlier and lasting 125 to 130 days compared to only 65 days in the past.
The study also highlighted that seasonal transitions are becoming more abrupt. Scott emphasized that people’s perceptions align with the data, which affects various aspects of life, including agriculture and sports. Dr. Andrew Watkins, an adjunct professor, noted that relying on globally aggregated datasets could miss local variations, but concluded that longer summers and shorter winters are consistent with climate science. He raised concerns about the increased frequency of extreme weather events tied to climate change, urging for a reduction in fossil fuel usage. Professor Sarah Perkins Kirkpatrick from the Australian National University also affirmed the study’s findings, emphasizing the need for localized observations to validate these results.
