The Case of the Shifting Snow
Feb 5, 2020
Our new report analyzes long-term snow trends, shows what’s happening in your region of the country, and discusses how declining snowfall affects our climate, economy, and lives.
Climate Central’s analysis of fifty years of snow data found snow levels decreasing in the fall and spring across most of the nation, while winter showed a mixed record.
Results of examining long-term seasonal trends from 145 locations showed that 116 stations (80%) had decreased snowfall before December, and 96 stations (66%) had decreased snowfall after March 1. Winter proved to have a mixed record, with more snow in northern climates and decreasing snow in the southern regions.
Comparing average annual snowfall totals in the first (1970-79) and last decade (2010-19) of the study period allowed us to rank cities with the largest losses or gains in snowfall:
|Top 5 cities with snow losses||Top 5 cities with snow gains|
|Nashville, Tenn. (59%)||Mitchell, S.D. (77%)|
|Knoxville, Tenn. (52%)||Atlantic City, N.J. (71%)|
|El Paso, Texas (52%)||New York City (66%)|
|Albuquerque/Santa Fe, N.M. (50%)||Newark, N.J. (51%)|
|Springfield, Mo. (46%)||Marquette, Mich. (45%)|
WHAT YOU NEED TO KNOW
A warmer climate affects snowfall, melting snow into rain as it falls and when it’s on the ground. In the United States, winters are the fastest warming season for much of the country, the longest cold snaps are becoming shorter, and the number of days with temperatures below 32°F is expected to continue to decline across the country.
Counterintuitively, climate change is causing increased snowfall in some colder climates. Warmer temperatures cause more evaporation. Because warmer air “holds” more moisture—about an additional four percent of water evaporates per degree (F)—that additional moisture can fall as snow when temperatures are below freezing.
Snow (or the lack of it) has direct impacts on the economy, with consumer spending by snowboarders, skiers and snowmobilers adding an estimated $20.3 billion to the U.S. economy in the 2015-16 winter season.
HOW WE GOT THE DATA
Total annual and seasonal (fall, winter, and spring) snowfall data from 1970-2019 were obtained from the Applied Climate Information System. Average annual snowfall in the first (1970-1979) and last (2010-2019) decade of the study period was compared at each location that receives an average annual snowfall of at least five inches. Stations with more than 20% missing daily data (2 years) in either the first or last decade were excluded from the analysis. For the seasonal analysis that spanned the full fifty-year period, stations missing more than 20% of daily data (10 years) for any season over the study period were excluded. Seasonal snowfall trends were analyzed using linear regression analysis.
POTENTIAL LOCAL STORY ANGLES
What’s the snow forecast for where you live?
The National Weather Service’s Winter Page provides maps and forecasts for snow and ice in your area. Their Winter Weather Desk provides twice-daily updated forecasts for snow, freezing rain, and other wintry conditions around the country.
How is climate change impacting winter activities and tourism near you?
Last year, Climate Central issued the report On Thin Ice, about winters heating up with serious consequences for America’s cold-weather sports economy. Protect Our Winters, a non-profit advocacy group concerned with climate change’s effect on winter sports and recreation, published a 2018 economic analysis that contains state-level data. And here are links to national winter sports organizations that have searchable databases to find sources or activities near you:
And if you have a professional hockey team near you, check for local initiatives at NHL Green, the National Hockey League’s sustainability program that aims to lower emissions, conserve water and reduce waste so future generations can continue the tradition of playing hockey outdoors.
Tools for reporting on winter weather events near you:
Warmer temperatures can make winter storms more complicated, with sleet and freezing rain. Criteria for winter storm watches, advisories, and warnings can vary by region so check out your local National Weather Service office. The NWS also provides helpful information on how to stay safe in winter conditions, wind chill charts, and an explanation of the polar vortex. And the National Snow and Ice Data Center (NSIDC) has just about everything you need to know about snow.
LOCAL INTERVIEW IDEAS
The SciLine service, 500 Women Scientists or the press offices of local universities may be able to connect you with local scientists or climatologists who have expertise on the impacts of climate change on weather trends in your area.
NATIONAL INTERVIEW SUGGESTIONS
Jan 23, 2019
Despite the recent cold snap, warming is transforming America’s winters.
Jan 22, 2020
After the hottest decade on record, it’s clear that all seasons are feeling the warming effects of climate change. Winter cold snaps have been getting shorter across the U.S.
Nov 15, 2017
Lake effect snow is paradoxically trending upward as the Great Lakes warm, but as the atmosphere warms further in the coming decades, the snowfall trend will reverse.