These are the signs of early spring, no matter what the groundhog says

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On Thursday, a plump groundhog by the name of Punxsutawney Phil will make his annual appearance in front of hundreds of adoring fans to announce when spring will arrive. Phil will whisper the fate of our winter in “groundhogese” for the 137th time. If he sees his shadow on the ground, people can expect six more weeks of winter; if not, spring will come early.

But you don’t need Phil, arguably the most famous weather-forecasting groundhog, to predict when the next season will arrive this year. (Also, he’s only right about 40 percent of the time.) In many areas around the country, people can already see signs that spring is ahead of schedule. The arrival of these signals vary around the country, but the onset of warmer winter temperatures can push the development of plants and animals sooner in the season than normal.

The South typically experiences spring earlier than other regions, but even this year’s season is “20 to 25 days early” there, said Alyssa Rosemartin, an ecologist with the USA National Phenology Network, which tracks plant and animal observations through citizen scientists. “It’s never been that early before, so it is remarkable.”

Western Texas, southern Arkansas, southern Louisiana and eastern Mississippi are all experiencing their earliest spring in 40 years of records from the phenology network, although growth has slowed with a recent cold spell. Spring in Alabama, Georgia, North Carolina and South Carolina arrived 1-2 weeks earlier than average.


Most places east of the Rockies are ahead of schedule for spring

Heat accumulation (accumulated growing degree days) across the U.S. since January 1, compared to the 30-year average (1991-2020).

Source: USA National Phenology Network

TIM MEKO/THE WASHINGTON POST

Most places east of the Rockies are ahead of schedule for spring

Heat accumulation (accumulated growing degree days) across the U.S. since January 1, compared to the 30-year average (1991-2020).

Source: USA National Phenology Network

TIM MEKO/THE WASHINGTON POST

Most places east of the Rockies are ahead of schedule for spring

Heat accumulation (accumulated growing degree days) across the U.S. since January 1, compared to the 30-year average (1991-2020).

Source: USA National Phenology Network

TIM MEKO/THE WASHINGTON POST

In southern Louisiana, early signs of spring include flowering American elms, leaves sprouting from herbaceous thistles and a surge of pollen from bald cypress trees, said Julie Whitbeck, an ecologist at Jean Lafitte National Historical Park and Preserve. There and across the Gulf Coast, red maples have begun to bloom, with helicopter-like fruit decorating their branches with crimson.

Other places are also experiencing early springlike flourish, according to the phenology network. Red alder trees began budding in Oregon and British Columbia in January, its earliest appearance in 14 years of records. Tulip trees in Indiana are flowering more than a month ahead of schedule. Forsythias are breaking leaf buds in Maine, an event that hasn’t been observed on record before March. Quaking aspen trees in Minnesota are producing flower buds, which typically isn’t seen until mid-February to mid-April.

Data suggest these spring signals are the result of consistently mild temperatures since a pre-Christmas intrusion of Arctic air across the country. Many locations east of the Rockies experienced their warmest January on record, according to the Southeast Regional Climate Center. Average temperatures as much as 6 to 10 degrees above normal set records from McAllen, Tex., on the Rio Grande to Houlton, Maine, on the Canadian border.

Those extra degrees make a big difference for some plants and animals.

Heat accumulation is one of the main ways to predict life cycle transitions in plants and animals, according to the phenology network. Many plants and animals need to experience a certain level of sustained warmth to trigger budding or egg hatching, which researchers measure using “growing degree days.” Growing degree days essentially measure the warmth needed to allow an organism to grow.

For an early spring to arrive, it would mean the plants and animals experienced more warmth than usual, more quickly achieving their required number of growing days.

On the other hand, cooler temperatures could push back the development of plants and animals, as seen in California and Arizona, which are lagging about a week later than normal.

It’s not just plants responding to the early warmth — some animals are also already declaring an early spring. Gina Lloyd, citizen science coordinator at the Barataria Preserve south of New Orleans, said she began to hear the chorus of calls from frogs known as spring peepers in late January — sounds that denote the beginning of their breeding season and are associated with heavy spring rains.

“I’ve been seeing a lot more frogs than I usually do in January,” Lloyd said. Snakes, too.

This year’s early spring signs follow a larger warming trend in recent decades. Analysis shows winters are warming faster than any other season in the United States. Over the past 50 years, average winter temperatures have warmed by at least one degree Fahrenheit in every state; 70 percent have seen increases of at least three degrees. The length of winter is also shrinking across the globe, studies show.

“Climate change is increasing the chances of everything related to this: of warmer winters, of shorter winters, of earlier springs,” Rosemartin said.

(Side note: Phil should probably incorporate these climate findings moving forward. Based on Phil’s past predictions since 1887, he is more likely to predict a longer winter — forecasting a longer winter 78 percent of the time and an early spring only 15 percent of the time. )

Early plant growth and active animals could be vulnerable to bouts of severe weather in the winter season.

This winter, many of the same areas along the Gulf Coast where early spring emerged were rocked by severe January thunderstorms, which are much more common in March and April. The storms — fueled by abnormally warm gulf waters — spawned destructive and deadly tornadoes. The National Weather Service’s Storm Prediction Center received 124 preliminary tornado reports last month, mostly in the South. The average January number is closer to 50.

Rosemartin said it’s possible that such destructive storms could bring more damage to budding plant tissues or branches that would otherwise still be dormant.

Still, research shows that while climate change is making winters warmer overall, intense cold snaps are still possible and winter could still bring frosty weather. Meteorological winter continues through the end of February in the Northern Hemisphere, and wintry weather can often occur even into March and April, when meteorological spring begins.

The first measurable snowfall of the season was observed early Wednesday along the Interstate 95 corridor, ahead of a brutal blast of cold expected in the Northeast on Friday and Saturday. In the southern United States, an intrusion of cold air is driving icy weather.

In Texas, winter storm and ice storm warnings covered most of the state on Wednesday, and temperatures were expected to remain below freezing for up to four days. It might not be clear until spring arrives in earnest what, if any, damage that might cause to early plant growth, said Courtney Blevins, Fort Worth regional forester for the Texas Forest Service.

“We don’t usually stay below freezing for more than a day or two,” he said. In past years, freezes have devastated crops that bud early in the South, driving fruit prices up.

In areas where mild January temperatures have kept the ground from freezing, that has allowed water to soak into soil and provide a growth signal for trees, Whitbeck said. It could also help protect those ecosystems from future cold snaps, she added. It takes longer to heat and cool hydrated soil than it does dry soil, so any drop in temperatures would need to be particularly harsh or lasting to freeze saturated ground.

In southern Louisiana, for example, there’s still a risk that such a harsh freeze could materialize. “The first three weeks of February are still fair game for a hard freeze,” Whitbeck said.

Even though there are signs of spring, winter may still bring some frosty weather. That’s a lot of nuance for a groundhog to predict.

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