The change of season from winter to spring is a welcome time of year, with our ice-covered Valley landscape a distant memory. Although we routinely benefit and suffer from the attributes of ice, we pretty much take it for granted.
There are trays of it in our refrigerators. We cool drinks with it and use it to soothe injured muscles. We express our artistic side by making ice sculptures and figure skating. There’s an adrenaline rush when our cars skid on it, and we curse the ice-covered driveway as we shuffle to the mailbox to get the newspaper. Ice, a liquid turned solid, is all around us.
Keeping perishables cool a century ago was not as easy as heading to the refrigerator. Last February at the Easthampton Winterfest I met with Westfield historian Dennis Picard, an ice-harvesting expert. As Picard explained at his Nashawannuck Pond ice-harvesting demonstration, “One hundred men could harvest three acres a day, laying a grid over a pond to guide the cutting of 100-pound blocks. Nashawannuck’s ice house could hold 6,000 to 8,000 tons of ice in a season.”
Ice was provided year-round to railroads for shipping perishables or delivery to homes for iceboxes. With the advent of electrification and refrigeration technology, the demand for harvested ice declined in the early 1900s and large commercial harvesting operations gradually disappeared. Fossil fuels used to create electricity replaced the brawn of humans and animals alike, as the United States shifted from an agrarian to industrial economy.
Although ice harvesting is a thing of the past, water freezing into ice is a basic fact of the Earth’s chemistry. Liquid water molecules — H2O — are always moving, speeding up and slowing down depending on temperature. The hotter the water, the faster the molecules move. The opposite happens as water freezes at 32 degrees Fahrenheit. The molecules slow down and through their natural attraction to each other, line up together to form crystals, a solid. Those 100-pound ice blocks were water molecules that slowed way down and stuck together.
With last winter’s cold snap there were plenty of examples of ice across the Pioneer Valley landscape. The Connecticut River froze for miles. Along Route 2 the Deerfield River overflowed with ice, depositing car-sized floes along its banks. Ice fishers were scattered across lakes and ponds. These local conditions link us to a larger global system, the “cryosphere,” or places on the planet where ice and snow exists for all or part of the year. Within the cryosphere, the Arctic and Antarctic regions stand out for their vast expanses of ice and snow.
Although similar in size — about one-third larger than the continental U.S. — the Arctic and Antarctic are very different regions. Antarctica is one of the seven continents and surrounded by ocean. A massive, permanent ice sheet covers the continent and its South Pole. The Arctic is predominately the ice-covered Arctic Ocean,surrounded by the land areas of seven nations, including the United States. The North Pole is actually in the Arctic Ocean. Historically, large areas of the Arctic Ocean have been covered with sea ice year-round, with the maximum extent of ice expanding in the winter and shrinking in summer.
The Arctic was in the news this past winter due to its having unusually warm temperatures. In the depth of winter, temperatures around northern Greenland historically averaged -4 F. This past February, temperatures spiked well above freezing at 43 F. That was the same temperature the day of the Easthampton Winterfest, 4,000 miles south. On the northern coast of Alaska, temperatures reached 31 F, where the average temperature is -7.3 F — well above the normal range.
Rising temperatures are melting ice at a time of year when, historically, ice is being created and reaching its annual maximum extent. The National Weather Service in Alaska reported that in the last two weeks of February, in the Bering Sea, an area of ice the size of Minnesota disappeared.
Nashawannuck Pond ice forms every winter with freezing temperatures, melting each spring. That’s normal. So, why worry about melting ice in the Arctic? The Arctic is considered one of the planet’s air conditioners and sea ice plays a critical role in maintaining the planet’s climate. Sea ice is a bright surface that reflects warming sunlight back into the atmosphere. As sea ice diminishes, more of the darker ocean surface is exposed, absorbing more of the sun’s energy and melting ever more ice. As this cycle continues, NASA is reporting a sea ice decline of over 13 percent per decade since 1980 and an increasingly warmer Arctic.
A warmer Arctic Ocean impacts the millennia-old movement of weather and climate regulating atmospheric and ocean currents around the globe. It also affects Arctic weather systems such as the Polar Vortex, a pattern of wind currents that traps cold air in the Arctic. When these Arctic systems change or falter due to warming, we get what are being classified as extreme weather events.
This past February, as the Polar Vortex broke down, Europe experienced extended subfreezing temperatures, including a rare snowfall in Rome. Simultaneously the Arctic had a heat wave, and our Winterfest was less than “wintry.” As Walt Meir, a scientist at the National Snow and Ice Data Center, put it, “The Arctic isn’t Las Vegas. What happens in the Arctic doesn’t stay in the Arctic.”
Tom Litwin is a conservation biologist and former Director of the Clark Science Center at Smith College. He is recently retired from the Jackson Laboratory in Bar Harbor, Maine and Farmington, Connecticut, where he served as the Vice President for Education, and continues as a visiting scholar. More on Litwin’s Arctic and Bering Sea Thin Ice research.
Earth Matters, written by staff and associates of the Hitchcock Center for the Environment at 845 West St., Amherst, appears every other week in the Daily Hampshire Gazette. For more information, call 413-256-6006, or write to us.