Fewer Rainy Days Are Bringing Earlier Springs
TUESDAY, March 1, 2022 (HealthDay News) — No matter what the calendar says, your plants will tell you when spring is coming. And even in the northern regions, they are withering earlier than ever in recent decades due to climate change. IN new study Researchers attribute early gardening to two key factors: warmer temperatures and fewer rainy days.”This contrasting effect at the beginning of the year makes the plants think it’s spring and begin to leaf out earlier and earlier,” study co-author Jian Wang said in a press release from Ohio State University. He is a doctoral student at the Faculty of Geography.
“Scientists have basically looked at how temperature affects the appearance of the first leaves, and if they were looking at rainfall at all, it was only rainfall,” said study co-author Desheng Liu, a professor of geography at Ohio State. “But the most important thing is not the total rainfall, but how often it rains.”
For the study, the researchers analyzed data from the US, Europe, and China, as well as satellite imagery showing when vegetation began to turn green from 1982 to 2018.
With fewer rainy days over the years, spring arrived earlier in most parts of the Northern Hemisphere. The only exception was pastured in semi-arid regions, where the season was slightly delayed.
The researchers proposed two key reasons why fewer rainy days result in an earlier start of spring for plants.
Rainy days are overcast days, so less of them in late winter and early spring means plants get more sunlight early in the year, which encourages leaf growth.
Fewer cloudy days also mean daytime temperatures are warmer and nighttime temperatures cool faster and clouds don’t hold heat.
The results were recently published in the journal Nature climate change.
The US National Park Service has more information on climate change and plants.
SOURCE: Ohio State University press release February 17, 2022