Spring comes early, bringing balmy days – and climate questions

Spring-like temperatures have arrived between two and three weeks early this month in various parts of the United States. 

First Look

Forget what Punxsutawney Phil’s shadow showed – spring is making its way to large swathes of the country between two and three weeks ahead of schedule, according to a study from a federal agency.

Unseasonably warm temperatures have hit coastal California, southern Nevada, southeastern Colorado, and several Midwestern states as well as parts of the Northeast, according to new maps produced by the USA National Phenology Network, which is led by the United States Geological Survey agency. While shedding some layers and enjoying nice weather in February has come as a treat for many, the unexpected weather changes could pose economic and environmental challenges.

“While these earlier springs might not seem like a big deal – and who among us doesn’t appreciate a balmy day or a break in dreary winter weather – it poses significant challenges for planning and managing important issues that affect our economy and our society,” Jake Weltzin, a USGS ecologist and the executive director of the USA-NPN, said in a statement.

Those include an influx in harmful insects, such as ticks and mosquitos, as well as increased pollen that can create complications for those with allergies. And while an earlier start to growing season could prove a boon for the agriculture industry, a return to seasonal winter temperatures could bring snow or frost, killing crops that started growing too soon.

Further economic impact can come from changes to recreational activities, such as hunting and fishing season and other outdoor activities, according to the USGS statement.

February, which is typically the third-coldest month of the year, saw unusually high temperatures during its first three weeks, shattering more warm-weather records across the country than cold ones.

"For every cold daily-temperature record we've broken in February, we've broken 62 warm daily-temperature records," Jake Crouch, a climate scientist for the National Centers for Environmental Information in Ashville, N.C., told Live Science. "That ratio is very high. In a normal situation, we would expect those to be a 1-to-1 ratio."

With limited data, climate scientists haven’t determined exactly why this February saw warmer temperatures than usual in nearly every part of the US. But they do believe the Arctic polar vortex, which sometimes brings a punch of cold air to the US, instead had greater impact on Russia and northern Europe, which saw “fairly cold” winters, according to Mr. Crouch.

It’s unclear if the average February temperature will set a record, as researchers continue to gather daily data throughout the month. But an unprecedented spring-like February would follow three years of record year-round average temperatures, with 2016 marking the hottest year since researchers started collecting the data in 1880, and continue a trend that has raised concerns among scientists. Scientists have known for more than a decade that climate change has been setting spring into motion earlier than before, according to the USGS. 

“A single warm year is something of a curiosity,” Deke Arndt, the chief of global climate monitoring a the National Oceanic and Atmospheric Administration, told The New York Times last month. “It’s really the trend, and the fact that we’re punching at the ceiling every year now, that is the real indicator that we’re undergoing big changes.”