At Large : Meaningless data
By Doug Cabral
Published: January 28, 2010
I keep informal track of ocean water temperatures nearby. The changing array of temperatures over time seems meaningful, but applying a theory to the data, never mind a conclusion, is impossible. At least for me.
For instance, early in the year in 2006, the surface water temperature in Woods Hole was 40 degrees. Today, it's 37. Then, measured offshore, southeast of the Vineyard, it was warmer, about 44. Today, off South Beach, it's 37. Have we been warming or cooling?
Studies of coastal sea surface temperatures, done by scientists from the University of Rhode Island and the Woods Hole Oceanographic Institution, and reaching back through nearly continuous records from 1886, show that there was no significant trend up or down at Woods Hole until the mid-1940s, when water began to warm a little. Then there was a bit of cooling during the 1960s, but after that, Woods Hole heated up during the years 1970-2002, at an annual rate of less than four hundredths of a Centigrade degree. I don't know if that's rapid heating or not.
Puzzlingly, the scientists found that during this period, summers weren't significantly warmer or cooler, and winters not significantly cooler or warmer. Plus, seasonal warming and cooling haven't appeared earlier or later each year. So, I ask you, what do you make of that?
This winter, December 2009, ought to have had a mean daily temperature of 35 degrees Fahrenheit. Instead, December was a snowy, frigid bear of a month. This month, January 2010, ought to have been colder, because historically January's mean temperature is 28 degrees. But, it's been milder. These are not scientifically compelling data points, of course, and they do not suggest anything at all about global warming. But, if you measure the quality of any particular winter the way I do, winter 2009-2010 has already been colder and harder than many, and surprisingly, milder and wetter than some. Of course, the late chapters have yet to be written.
For me, a wicked winter is one in which there is harbor ice to chop in Vineyard Haven, a jam of ice in Woods Hole when the current is ebbing, and a mosaic of ice and sea smoke over Nantucket Sound. When winter has met each of these standards, you can be sure it's been terrifically cold for a long time. There may even be skating and ice boating ice on Squibnocket Pond. That's a wicked winter. In forty years of informal, occasional, unscientific, undocumented observation, I can say with confidence that such winters have been rare.
Sometimes winter is cold and snowy, but there's no ice in the harbor or the sound, and sometimes winter is mostly benign but three February weeks of nasty cold and harsh northwesters will depress water temperatures and cause ice to build in both places. All weather - and I'm talking about weather, not climate - is, like politics, local.
Another distinguishing characteristic of a wicked winter is ice gathered around the pilings that support docks along the Eastville shore. After a cold front passes, the northwest wind whips the water against the pilings, and each splash freezes until all the pilings wear spats, frozen in place. I suspect the wind turbines planned for Horseshoe Shoals will sport some icy duds during parts of some winters.
Aboard fishing vessels, wind chills are more than mere couturiers. Scallopers and draggers that fish offshore find the water warmer than inshore. Except that they often get caught in winter storms, the conditions in which they fish on George's Bank and vicinity are more benign than we might imagine. But, bound home, shouldering the northwesterlies and the frigid sea, and deep with a heavy, profitable trip, these 90-footers hurl up spray that freezes on deck, bulwarks, superstructure, and in the rigging, adding weight where it's dangerous. The crew will have to chop the ice away. Nasty work, at six knots, plunging into a frigid head sea, with 100 sea miles to run to get to market, all of it upwind.
With temperatures in the thirties and forties this month, gentle January has taken a big bite out of winter. A February deep freeze could turn winter around, but harbor ice is unlikely to form, no matter what. My prediction. Many winters, snowy as they were, made no significant salt water ice, but the winter of 2003-2004 froze the west end of the Lagoon Pond solid and Vineyard Haven Harbor as well. For several days, a seal sunbathed on an ice floe (bear with me) just off the beach near the office. Some days you could paddle out to your boat at her mooring behind the breakwater. A few days of westerlies and the ferry's passage into and out of her slip freed ice from behind the breakwater and shifted it toward the outer harbor. Other days, six inches of soft, undulating, saltwater ice surrounded the boat. It looks as if it would support someone intrepid enough to step from the skiff onto the ice sheet, but of course it would not. The boat was unapproachable, held by the ice, her stern to the wind, just beyond reach.
This year, the early snow has succumbed to January, and the anti-winter crowd among us search for green shoots in the perennial garden in front of the house. The garden attracts rabbits who scatter like the trails of tracer rounds in the dark as we arrive home from work. We fondle the buds on the bushes near the house - and dream of May. The deer drop by every day also, looking for anything young and green. Of course the dogs never notice. They are shams who hold themselves out as family guardians, but it's a joke. It's not a winter like last winter, nor like the one before. It's a snowy, rainy, frigid, mild, icy, ice-less winter, better than some I can remember, not as nice as others, and it may change altogether next month.
