Northern seasons are shifting: study
March 28, 2014 3:00AMSCIENTISTS have discovered a shift in the northern seasons, with spring arriving early and autumn being delayed.
Peter Atkinson, professor of geography at the University of Southampton, has examined satellite images of vegetation across the northern hemisphere from the past 25 years and found signs that winter is being shrunk.
Earlier this month, supermarkets Waitrose and Tesco both announced that English strawberries were ripening early and hitting the shelves a week earlier than last year.
"There is much speculation about whether our seasons are changing and if so, whether this is linked to climate change. Our study is another significant piece in the puzzle, which may ultimately answer this question," Atkinson said.
The researchers examined a range of vegetation types with forests which have not been affected by human intervention acting as the best signifier for the changing seasons.
The most pronounced change found by the researchers was in the broad-leaved deciduous and needle-leaved deciduous forest groups, showing that autumn is becoming significantly later with an early onset of spring.
"Previous studies have reported trends in the start of spring and end of autumn, but we have studied a longer time period and controlled for forest loss and vegetation type, making our study more rigorous and with a greater degree of accuracy," Atkinson said.
"Our research shows that even when we control for land cover changes across the globe, a changing climate is significantly altering the vegetation growth cycles for certain types of vegetation.
"Such changes may have consequences for the sustainability of the plants themselves, as well as species which depend on them, and ultimately the climate through changes to the carbon cycle."
The project, which involved scientists from the Department of Remote Sensing at the Birla Institute of Technology in India, is published in the journal Remote Sensing of the Environment.