A December for the weather books

Monday, January 11, 2016

by SUSAN MANN

All of that December warmth and Environment Canada's prediction of a return to milder or normal temperatures in most of Ontario for the rest of winter may prove a boon to Ontario’s apple and tender fruit trees.

So far, this winter’s fluctuating warmth and cold have not damaged fruit trees or grape vines. In fact, Charles Stevens, chair of the Ontario Apple Growers board, says all that warmth may be good for apple trees.

“The apple trees haven’t had to use as much energy to keep warm as they have in other years,” he explains. Stevens says apple trees store carbohydrates built up during the summer in their bark and use “that to keep alive in the winter time.”

Similarly, tender fruit trees are also doing okay. “I’ve been talking to growers and there’s no concerns,” says Sarah Marshall, manager of Ontario Tender Fruit Growers.

The trees are still naturally going into hibernation despite the temperatures, she explains. “They are showing that they are still resilient to really low temperatures.”

Marshall says the tender fruit board monitors how hardy the trees are in the winter. “We monitor the low temperatures. If it got to be -20 C for several days, then there might be some concerns.”

For grape vines, Debbie Zimmerman, CEO of Grape Growers of Ontario, “things are looking okay.”

Icewine producers caught a break earlier this month when there were a couple of cold snaps so “the majority of the icewine grapes are off,” she says.

Icewine is made from fully mature grapes left on the vines to freeze and then they are picked and pressed while frozen. Temperatures must drop to -8 C or lower before the grapes can be harvested for icewine.

Environment Canada senior climatologist Dave Phillips says “I’ve been in this business for 48 years and I shake my head about what we saw in December. Often we break records by a tenth of degree and I get excited.”

However in December, warm temperature records in some cases were broken by more than two degrees, he says.

Phillips says December’s warm temperatures hit all areas of the province.  “It wasn’t just about a Toronto urban heat island or down in Windsor.”

He notes it was 19 C in Cornwall on Christmas Eve. “That would have been warmer than what you’d expect in Tallahassee, Florida at that time.”

The average temperature for Windsor in December was 4.7 C, beating the old record of 3.1 C by one and a half degrees, Phillips says. In Toronto, the average temperature for December was 5.1 C, while the previous record was 3.2 C.

For Ottawa, December’s average temperature was 1.2 C, while the previous record was — 1.4 C. That is almost “three degrees warmer than the previous record,” he notes.

Phillips says it was El Niño that caused the warm weather anomaly in December. El Niño is an irregular climatic event that occurs when there is unusually warm water in the Pacific Ocean near the regions of Peru and Ecuador.

“It was clearly El Niño in action,” he says. BF