As the nation basks in some of the warmest February weather it has seen in decades, the U.S. Geological Survey has been quick to point out that the early spring conditions are another symptom of climate change.
On Thursday, the USGS shared a new analysis just released by the USA-National Phenology Network, which the agency helps to fund, showing that an early spring has already swept through the Southeast and is continuing to work its way across the country. As the agency points out, the new analysis reaffirms a fact scientists have known for at least a decade now — that “climate change is variably advancing the onset of spring across the United States.”
The analysis relies on a special “spring index,” which defines the start of spring as the point when temperatures allow for certain early-season events in plants, such as the emergence of leaves and blooms. The index was created using data that has been collected for a citizen science project over the past few decades, according to Jake Weltzin, executive director of the USA-National Phenology Network and an ecologist with the U.S. Geological Survey, which helped fund the project.
Since the 1950s, volunteers have been collecting information about the leafing and blooming of certain plants, such as lilacs and honeysuckle, Weltzin said. More recently, climatologist Mark…