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It’s Canada Day, 2067 — our bicentennial.
In Ottawa, the peach trees have lost their blossoms and young fruit are developing nicely as mockingbirds and blue grosbeaks hop from branch to branch.
The kids are slathered in sunscreen. It’s uncomfortably warm in the city — not very pleasant weather for the Canada 200 ceremony on the Hill — and people are crowding the beaches, despite some early hints of smelly blue-green algae. The catfish are biting nicely. Dad keeps talking about the trout that lived around here, back in his day.
Politicians are debating what to do about the latest flood damage. The Ottawa and Gatineau rivers have once again inundated homes on shorelines and in old sections of Gatineau. You’d think the heat would dry up all that water, people say, but rain just keeps falling. It also washed out a lot of Eastern Ontario’s cornfields — again.
Photos on the wall recall a childhood, decades ago, when people used to skate outdoors. At least there’s road hockey, though in the afternoon the kids have to come inside to cool off.
Police hate this weather. It brings out the worst in people, especially the steamy nights when tempers, like city pavement, get no chance to cool off.
The latest round of climate projections is just out as well. More warming is coming, of course.
Climate change will have an effect on our lives here in the capital. Digital illustration by Rob Cross
This is, admittedly, just one vision of the future and of climate change.
Canadians are often told that the temperature will warm up and the world around us will change, somehow. But government projections tend to be vague on details, or give sweeping forecasts for huge areas of the country all mashed together.
The Citizen set out to ask a question to experts in climate, in natural world issues such as forests and farms and lakes, and in human health: What will Ottawa’s local climate be like later in this century as climate change takes its toll? How will our actions today shape our future lives?
Together they have painted a picture of our region as our grandchildren, or even our children, will see it.
So how many degrees warmer will it be?
There is no single answer, a fact that frustrates policymakers and the public alike. We want someone to tell us: “Ottawa will be 2.3 degrees warmer by a fixed date.” It would give us something to talk about in concrete terms of global warming and climate change. The experts won’t venture into those kinds of specifics.
The reason? We don’t know how much more climate-warming gas our society will produce in future decades.
Experts, you see, believe we get a say, that we have some agency in this unfolding planetary narrative.
So any predictions rely on a range of models — one model for the “business as usual” future, in which we act pretty much as we do today; another for a possible future in which we take some modest new actions; yet another for a future in which everyone enthusiastically stops burning fuel to drive cars, heat homes or generate electricity.
For decades, we’ve been promised new technology to make the future pollution-free.
In 1989, the provincial natural resources ministers agreed to cut 20 per cent in greenhouse gasses. The city of Ottawa promised a cut of 50 per cent a few years later. The Kyoto protocol was an international promise to reduce emissions by more than 30 per cent. There have been global agreements in Copenhagen (minus Canada that time), and in Paris with new targets.
But targets are only good intentions. Actual emissions keep stubbornly rising.
We asked David Phillips, Environment Canada’s senior climatologist, what our future climate will be like. He turned to a group of mathematical modellers at York University, the Laboratory of Mathematical Parallel Systems.
They, in turn, looked through dozens of different computer models of future climates and gave data to Phillips, who asked himself: “What will Ottawa look like in 50 years, on Canada’s 200th birthday?”
Related
The York numbers are projections for two 30-year periods in our future: the middle of the century (2040 to 2069) and the late century (2070 to 2100). Phillips started comparing projections.
For instance, Ottawa has an annual mean temperature — the figure you get by averaging all the highs and all the lows for a year.
Our mean today is 6.4 C — neither hot nor freezing, like a pleasant morning in April. But the mid-century mean, if we continue our present habits, is projected to rise to 9.6 C, and the late century mean is 11.9 C.
That is to say, the average of an entire year’s temperatures is expected to rise by about 5.5 degrees by the end of this century if we keep on burning fuel. That is a greater increase than the global average forecast, which foresees a rise of between 1.8 and four Celsius degrees by 2100.
Of course, we don’t usually think in terms of annual mean temperatures. We think about summer and winter separately, because that is how we experience our years. So, Phillips examined those.
Environment Canada’s senior climatologist Dave Phillips.
You call that winter?
Get ready for skating to be something we usually only do indoors.
The average high in January today is -5.6 C. By mid-century, we can expect average highs of -2.2 C, and by the end of the 2000s it is expected to be 0 C.
Today we get about 80 days each year with a high below freezing. By the mid-century, that’s likely to drop to 56 days, and then 38 days late in the century.
And Phillips says we get about 40 days or nights that drop below -15 C today. Expect that to be reduced to 17 and then all the way to six days in the two later periods. Nights below -15 C are critical for building solid ice in the Rideau Canal, he notes, raising the possibility that the weather will be freezing, but not a really hard freeze.
We get 18 days a year below -20 C, but can expect only three a year in our future — about the same as Toronto gets at the moment. And you know how much outdoor skating they have.
What about snow?
Ottawa’s odds of a white Christmas are traditionally about 85 per cent. But Phillips sees that falling to 40 per cent by the end of the century. (Cruelly, while we’ll get less snow, we can expect slightly more freezing rain in the future.)
Migrant workers pick ripe peaches at Tregunno Farms in Niagara-On-the-Lake.
Summer sounds just peachy
Maybe you should consider planting peach trees.
Today we average 13 days per summer above 30 C, though this varies a lot. We had barely any this past summer, but far more than average last year. Still, it’s a starting point.
The models call for an average of 42 such days by mid-century, and 67 each summer — in effect, every day in July and August and a few left over — by the late 2000s.
Phillips is more focused on the nights.
“In a heat wave, it’s the nights that kill people,” he said. The body doesn’t have a chance to cool off, to sleep and to recharge.
Today, we average only seven nights each summer that stay above 20 C. By the late part of the century, look for that to rise to 52 nights, the equivalent of nearly two months.
So who has weather like this today?
Phillips says it’s a pretty close parallel to Columbus, Ohio, where the last major snowfall was in 2008. Average winter highs are a couple of degrees above freezing, and a typical July day reaches 30 C. No one in Canada today has summers like that.
The expected growing season and summer temperatures of Canada in 2067 line up closely with the thin strip of land near Lake Erie, stretching from Windsor to Niagara. (Biologists call this the “Carolinian zone,” and it is already home to warm-weather plants and animals that thrive nowhere else in Canada, such as the tulip tree and barn swallow.)
Gardeners should take note. Ottawa is now in a “plant hardiness zone” called 5B, on a scale where higher numbers indicate longer, warmer growing seasons. Expect a jump to the much warmer zone 7A by the late century, Phillips says. Today the Windsor area and the Niagara fruit belt — a warm region growing wine grapes, cherries, peaches and nectarines — are in 7A. (Note, these are Canadian zones. The U.S. system includes Canada but its numbering is different.)
Heat hits the capital in this 2012 file photo.
Climate change will be deadly
Take today’s annual mean temperature of 6.4 C. In the best of possible futures, it will still rise to 8.4 C by mid-century and stay there until 2100.
In a future with moderate pollution improvements it will rise to 8.9 C and then to 9.6 C late in the century. That’s more than three degrees of increase. It’s less than the worst case (a rise of 5.5 degrees) but still enough to cause trouble.
Most obviously, extra heat is bad for our health.
READ MORE: Age & health are big factors in heat wave deaths, study shows
More Canadians will die in a hotter climate. That’s a harsh statement, but a factual one. While it would be rash to predict numbers, it’s worth noting some proven trends.
For starters, Health Canada uses an analysis of the number of people who die in the city of Winnipeg, related to heat. They don’t count trauma deaths — vehicle accidents, falls, and so on.
Their conclusion: “At approximately 26°C/78.8°F excess mortality begins to increase as ambient temperatures increase; the increase in deaths becomes much more pronounced above 35°C/95°F.” (These are actual temperatures, not humidex.)
The City of Toronto’s public health department estimates that city has 120 deaths a year from heat.
Health Canada notes that “In 2010, Montreal experienced a heat event (July 5 – 11th) where there were 304 reported deaths from all causes in Montreal residents, of which 106 were heat-related.”
As a side note, cities are in a special category. They are known in the climate business as “urban heat islands” whose asphalt and concrete are hotter than rural areas nearby. Cities can be one to three degrees hotter in daytime. But the real difference comes at night. Because pavement and rooftops hold heat, they can be up to 12 degrees warmer at night than the greener countryside. Humidity increases this effect. It also makes the human body less able to lose heat by sweating, because a person is surrounded by moisture, and you’re basically trying to make sweat evaporate into a cloud.
It’s hard to count heat-related deaths, notes Martha Robinson of Ottawa Public Health, because in the emergency room it’s not clear who is suffering from heat alone and who has heart or respiratory trouble. Often, several factors are jointly to blame.
In August of 2003, a two-week heat wave killed more than 14,000 people in France — yes, really. Many cities reported reaching highs of 39 to 40 C during the hot spell, and temperatures throughout the country were mostly five to seven degrees above normal.
Many of those who died were elderly but fit enough be living alone, while the more frail of the elderly were in air-conditioned nursing homes or having someone oversee them.
Elderly people suffer more in heat because their bodies are less efficient at shedding heat. And brick and stone French buildings that are normally efficient at cooling overnight were unable to cool during the heat wave, because the nights stayed warm.
Thousands more died in other countries in Western Europe.
• In the 1995 Chicago heat wave there were 739 heat-related deaths in the city in five days. Most of the victims of the heat wave were elderly poor people, who did not have air conditioning.
• In a far less severe heat wave in Ottawa in 2010, with temperatures of 34 to 35 C for six days, Ottawa’s paramedics reported that the number of calls they received for all causes rose by 18 per cent.
READ MORE: Why humid is worse than hot
One-year-old Nayden cooled off at Lansdowne’s water plaza Sunday September 24, 2017.
Tough rows to hoe
Farming will be harder. Mainly, says the dean of the Ontario Agricultural College in Guelph, it will be more unpredictable, which is the same thing.
“We are less worried about the term global warming (than) global climate change,” said Rene Van Acker. “In agriculture what really worries us, and the insurance companies can bear this out, is the variation around the mean and the decreasing predictability of what the weather will do. Irma frightens us in agriculture because (Hurricane) Irma is an example of the increasing strength of storms that comes with changing climate.
Irma, the strongest Atlantic hurricane since 2005, caused enormous devastation across the Caribbean in early September.
“We know in agriculture that our crop failures are driven typically by too much water or not enough water. Variations around that, and more extremes, are a tremendous challenge for us.”
If it were just a case of a slow rise in temperature, this wouldn’t bother farmers. Seed companies are used to breeding new hybrids; they already produce a range of corn and soybeans, for instance, that are suited to warmer and cooler regions within Ontario.
“But we know it’s not that.”
Ellie Renaud at her farm east of Village of Frankville, Ont. She and other local farmers will face climate-change challenges in the years ahead, experts predict.
You’re less likely to travel along a highway beside a uniform cornfield that stretches for miles, and more likely to a patchwork of different crops as farmers diversify their crops to diffuse the risk. Hybrid crops that are more drought resistant are also likely.
But you may also see crops that exist today only in the lab. One example: Perennial grains.
Today a farmer must plant corn, wheat and other grains every year. But there are prototypes of perennial cash crops — wheat and flax in particular — that offer the hope of more sustainable farming.
“Not that we would shift everything to perennials but we might want a short-term perennial in our rotation, Van Acker said.
“Those crops will respond differently to an extreme year than an annual crop,” he said.
Perennial plants have deeper roots than annual plants. “It is growing in the ‘shoulders’ of the season — early spring and late fall. It has a fundamentally different resilience” to insect pests.
“It tends to be more tolerant of both drought and excess water,” likely due to the more developed root structure.
If a perennial crop grows for several years in a row and is then replaced by another crop in a scheduled rotation, it even helps the new crop, because the perennial often keeps weeds in check.
Van Acker learned this as an undergraduate. He had a summer job selling herbicides and found dairy farmers were a tough sell: They grew alfalfa for three or four years as part of their rotation. It is a perennial “and alfalfa can do a lot to decrease your weed population. So the annuals they would plant after those alfalfa crops would almost not need herbicide. It’s just one example, but crop rotation is a fundamental tool for all kinds of problems we face.”
The impact means a less stable food supply and higher insurance costs for farmers. If crops fail more often, or if some crops become to undependable to plant in the first place, Canada becomes more dependant on imported food, and an important sector of our economy loses strength.
READ MORE: Rainy summer a ‘disaster’ for local farmers
Residents of Parc de la Riviera in Gatineau had to be evacuated after a rainfall washed out the streets.
Get ready for more flooding
Rivers will flow faster at times, more slowly at others.
The Mississippi Valley Conservation Authority is in luck. Back in the early 1900s, someone had the bright idea of measuring the flow of the Mississippi River at Appleton, and the records provide a century-long data set that is rare in this country.
The conservation authority feels that the pattern that is well established from all these years of data is going to change.
The spring runoff will start a couple of weeks earlier, in the future.
Hotter weather means that even with a rainier future our streams and rivers will flow even more slowly in late summer and early fall than they do today.
But by late fall the authority is expecting a surge upward in river flows, a result of two changes: more precipitation falling than today, and more of it falling as rain rather than snow once December arrives. The more extreme highs and lows in river flows mean bigger swings in water levels — greater chances of flooding in spring, and of water shortages in summer.
And more rains mean more floods. In late October, when floods once again swept through the Outaouais, Gatineau Mayor Maxime Pedneaud-Jobin told a radio interviewer flatly: “Our infrastructure isn’t designed for this.”
And he said he expects heavy downpours more often in future years.
The mayor of Chelsea, Caryl Green, says it’s time for municipalities to start building bigger culverts to prevent road washouts that seem to be increasing in frequency.
Algae photographed on Upper Rideau Lake in this file photo.
Algae and the affect on our lakes
The Rideau Lakes and others like them may look the same on top in 50 years, give or take some changing water levels as the lakes adjust to both greater rainfall and more evaporation.
The real change will be evident deeper down.
“One of the first things you’ll see is we are going to have less ice cover,” says John Smol of Queen’s University. He studies change in Eastern and Arctic lakes, and also studies lake sediments, which preserve the record of climates since the last Ice Age in the single-celled fossilized organisms that become more or less common as environmental conditions change.
“The easiest way to describe it is the summer is getting longer. That’s partly because of decreased ice cover, partly because ice comes off earlier,” he said.
Lakes are already showing hints of what is to come. They are forming layers that last longer, and these have an effect on what lives in the lakes, especially algae.
“Deeper lakes stratify into three layers,” Smol explains. “If you are ever treading water and suddenly your toes feel cold, that is because you have got into the deeper, cold water. Cold water is denser, warm water is less dense.”
They form distinct layers that do not mix, like a cocktail with different coloured liqueurs in layers (an effect that is also caused by differences in density.)
“You have isolated the lake into three sections much longer than you used to, even weeks longer. Blue-green algae really like it hot. And they do better under stratified (layered) unmixed water.” They also have a longer growing season if the ice cover doesn’t last as long, because there’s a longer period of sunlight shining into the water. Algae are plants and they use photosynthesis to get energy.
“So I think (this is) one of the reasons why we are seeing all these algal blooms, especially in August. … The blue-green algae can also form toxins for humans and other organisms.”
Another problem: starving fish of oxygen.
“The longer you keep the lake stratified in those three layers, the more you start losing oxygen in the deep waters. It is not being recirculated with the air up above. So a lot of the fish people like, like lake trout — they are being more and more stressed.” Trout and salmon are cold-water fish but they do need oxygen. “So we may start losing some of our most prized fish. That’s something we are already seeing happening.”
“Episodic” weather — heavy rains that cause flooding, and droughts that dry up wetlands — will cause bigger swings in water levels than we are used to.
And even massive forest fires affect lakes, especially on shorelines.
“The climate is like a big threat multiplier,” Smol said. “Almost everything is worse under a warmer climate.”
There’s already data showing that Muskoka lakes have a shorter ice season.
Green undergrowth is flourishing at the site of a forest fire near Moodie Drive in the summer of 2012.
Pining for the forest of old
At the University of Minnesota Center for Forest Ecology, Lee Frelich has concluded oaks and white pines will probably adapt well to climate change and that their populations may expand.
Beeches and red pines will not do as well.
“Oaks, through their evolutionary history, are well set up to take advantage of longer summers and more dry spells. They are drought-tolerant and they are able to use a six-or seven-month growing season a lot more efficiently than other tree species that you have there,” the veteran tree scientist says.
The white pine “can grow in a long summer or a short summer and it is very drought-tolerant.”
But his main point is that diseases and bugs that thrive on warmer temperatures, and also the increase risk of fires, are as much a threat to trees as the increased heat itself.
“There are just so many insect pests and diseases (in trees), you wouldn’t believe it. We have something like 471 of them that are present in North America now.”
He also points out that although trees can move farther north in a warmer climate, but they cannot adapt and move as fast as birds. Faced with a sudden and large-scale change in climate, he says, some forests will just die.
While his research is in Minnesota and Wisconsin, Frelich is also familiar with the forests of our region — an extension of the Great Lakes hardwood forests. He believes the future here will look a lot like what he studies at home.
“I think a lot of surprises are in store no matter how smart you are. A lot of surprises are in store.”
A robin hunts for supper in Ottawa.
Expect some ruffled feathers
Most birds around Ottawa will likely adapt, in time.
Still, migration is already becoming a struggle for some birds, says Bridget Stutchbury of York University.
“There are tons of studies showing earlier nesting, especially in species like the robin who don’t migrate very far — or at all. So, for instance, robins can sense our earlier springs because they only go a short distance south. In migratory terms, they don’t really leave our neighbourhood. But species that fly all the way to South America are not expected to notice, and adapt, as spring begins earlier.
“One of the big questions in climate change for songbirds is how quickly the long-distance migrants can adapt to warmer springs,” she says.
Migrating birds have been slowly adapting since the end of the last ice age, and they are experts today at flying north when the time is right. This is crucial to their ability to eat: Insect eaters have to arrive in Canada when there are insects to catch, for instance.
“Eventually they will (adapt),” Stutchbury believes. “It may take a generation, or two or three or four. There will be some time lag,” she predicts.
But in our hotter future, you may see birds nesting at the wrong time, missing the food bonanza that will happen a few weeks earlier than it did way back in 2017.
“The idea that there is a peak season when you can feed your kids. The peak in food abundance occurs at a particular time and the birds would time their egg-laying so that their kids would hatch out during that peak. And some research in Europe shows that there is (today) a mismatch between the peak of food and peak demand on the birds’ part.
“That will affect reproductive success, productivity. They won’t producing as many kids as they could if they nested in the optimal time of year.
“We know that will self-correct over time,” because each species has some early birds and some late arrivals every year, and eventually the early birds will be the ones raising lots of babies. So in the long run, Stutchbury sees most of our local bird species learning to live with change, but they may go through tougher times until that happens.
You may also see new birds at your feeder, southern residents that are pushing northward as the cardinal already has. (The first cardinal in Ottawa was recorded in 1945.)
Northern mockingbirds may come to Ottawa, Stutchbury believes. So may hooded warblers, which today live only in the southern fringe of Ontario near Lake Erie. The mockingbird is a grey, slender extrovert with a big personality and all kinds of different calls and songs. The hooded warbler is a little black and yellow forest bird.
“When it comes to birds, the (climate) concern is really not so much the birds we have around here. It’s more the Arctic birds and seabirds,” she said.
And so the view from Canada 200 is steamy, humid, but not without hope. Climate has never stayed completely stable, and humans have the ability to endure hardship and adapt to changing patterns of rainfall, terrible storms, changing conditions for agriculture, and waves of heat.
Today, since it seems unlikely that we will stop climate change, we can prepare for the next test of our ability to adapt to our changing Earth.
READ MORE: Will we never learn? Tom Spears looks at the hot air that abounds when politics meets greenhouse gasses
tspears@postmedia.com
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In Ottawa, the peach trees have lost their blossoms and young fruit are developing nicely as mockingbirds and blue grosbeaks hop from branch to branch.
The kids are slathered in sunscreen. It’s uncomfortably warm in the city — not very pleasant weather for the Canada 200 ceremony on the Hill — and people are crowding the beaches, despite some early hints of smelly blue-green algae. The catfish are biting nicely. Dad keeps talking about the trout that lived around here, back in his day.
Politicians are debating what to do about the latest flood damage. The Ottawa and Gatineau rivers have once again inundated homes on shorelines and in old sections of Gatineau. You’d think the heat would dry up all that water, people say, but rain just keeps falling. It also washed out a lot of Eastern Ontario’s cornfields — again.
Photos on the wall recall a childhood, decades ago, when people used to skate outdoors. At least there’s road hockey, though in the afternoon the kids have to come inside to cool off.
Police hate this weather. It brings out the worst in people, especially the steamy nights when tempers, like city pavement, get no chance to cool off.
The latest round of climate projections is just out as well. More warming is coming, of course.
•
Climate change will have an effect on our lives here in the capital. Digital illustration by Rob Cross
This is, admittedly, just one vision of the future and of climate change.
Canadians are often told that the temperature will warm up and the world around us will change, somehow. But government projections tend to be vague on details, or give sweeping forecasts for huge areas of the country all mashed together.
The Citizen set out to ask a question to experts in climate, in natural world issues such as forests and farms and lakes, and in human health: What will Ottawa’s local climate be like later in this century as climate change takes its toll? How will our actions today shape our future lives?
Together they have painted a picture of our region as our grandchildren, or even our children, will see it.
So how many degrees warmer will it be?
There is no single answer, a fact that frustrates policymakers and the public alike. We want someone to tell us: “Ottawa will be 2.3 degrees warmer by a fixed date.” It would give us something to talk about in concrete terms of global warming and climate change. The experts won’t venture into those kinds of specifics.
The reason? We don’t know how much more climate-warming gas our society will produce in future decades.
Experts, you see, believe we get a say, that we have some agency in this unfolding planetary narrative.
So any predictions rely on a range of models — one model for the “business as usual” future, in which we act pretty much as we do today; another for a possible future in which we take some modest new actions; yet another for a future in which everyone enthusiastically stops burning fuel to drive cars, heat homes or generate electricity.
For decades, we’ve been promised new technology to make the future pollution-free.
In 1989, the provincial natural resources ministers agreed to cut 20 per cent in greenhouse gasses. The city of Ottawa promised a cut of 50 per cent a few years later. The Kyoto protocol was an international promise to reduce emissions by more than 30 per cent. There have been global agreements in Copenhagen (minus Canada that time), and in Paris with new targets.
But targets are only good intentions. Actual emissions keep stubbornly rising.
We asked David Phillips, Environment Canada’s senior climatologist, what our future climate will be like. He turned to a group of mathematical modellers at York University, the Laboratory of Mathematical Parallel Systems.
They, in turn, looked through dozens of different computer models of future climates and gave data to Phillips, who asked himself: “What will Ottawa look like in 50 years, on Canada’s 200th birthday?”
Related
•
The York numbers are projections for two 30-year periods in our future: the middle of the century (2040 to 2069) and the late century (2070 to 2100). Phillips started comparing projections.
For instance, Ottawa has an annual mean temperature — the figure you get by averaging all the highs and all the lows for a year.
Our mean today is 6.4 C — neither hot nor freezing, like a pleasant morning in April. But the mid-century mean, if we continue our present habits, is projected to rise to 9.6 C, and the late century mean is 11.9 C.
That is to say, the average of an entire year’s temperatures is expected to rise by about 5.5 degrees by the end of this century if we keep on burning fuel. That is a greater increase than the global average forecast, which foresees a rise of between 1.8 and four Celsius degrees by 2100.
Of course, we don’t usually think in terms of annual mean temperatures. We think about summer and winter separately, because that is how we experience our years. So, Phillips examined those.
Environment Canada’s senior climatologist Dave Phillips.
You call that winter?
Get ready for skating to be something we usually only do indoors.
The average high in January today is -5.6 C. By mid-century, we can expect average highs of -2.2 C, and by the end of the 2000s it is expected to be 0 C.
Today we get about 80 days each year with a high below freezing. By the mid-century, that’s likely to drop to 56 days, and then 38 days late in the century.
And Phillips says we get about 40 days or nights that drop below -15 C today. Expect that to be reduced to 17 and then all the way to six days in the two later periods. Nights below -15 C are critical for building solid ice in the Rideau Canal, he notes, raising the possibility that the weather will be freezing, but not a really hard freeze.
We get 18 days a year below -20 C, but can expect only three a year in our future — about the same as Toronto gets at the moment. And you know how much outdoor skating they have.
What about snow?
Ottawa’s odds of a white Christmas are traditionally about 85 per cent. But Phillips sees that falling to 40 per cent by the end of the century. (Cruelly, while we’ll get less snow, we can expect slightly more freezing rain in the future.)
•
Migrant workers pick ripe peaches at Tregunno Farms in Niagara-On-the-Lake.
Summer sounds just peachy
Maybe you should consider planting peach trees.
Today we average 13 days per summer above 30 C, though this varies a lot. We had barely any this past summer, but far more than average last year. Still, it’s a starting point.
The models call for an average of 42 such days by mid-century, and 67 each summer — in effect, every day in July and August and a few left over — by the late 2000s.
Phillips is more focused on the nights.
“In a heat wave, it’s the nights that kill people,” he said. The body doesn’t have a chance to cool off, to sleep and to recharge.
Today, we average only seven nights each summer that stay above 20 C. By the late part of the century, look for that to rise to 52 nights, the equivalent of nearly two months.
So who has weather like this today?
Phillips says it’s a pretty close parallel to Columbus, Ohio, where the last major snowfall was in 2008. Average winter highs are a couple of degrees above freezing, and a typical July day reaches 30 C. No one in Canada today has summers like that.
The expected growing season and summer temperatures of Canada in 2067 line up closely with the thin strip of land near Lake Erie, stretching from Windsor to Niagara. (Biologists call this the “Carolinian zone,” and it is already home to warm-weather plants and animals that thrive nowhere else in Canada, such as the tulip tree and barn swallow.)
Gardeners should take note. Ottawa is now in a “plant hardiness zone” called 5B, on a scale where higher numbers indicate longer, warmer growing seasons. Expect a jump to the much warmer zone 7A by the late century, Phillips says. Today the Windsor area and the Niagara fruit belt — a warm region growing wine grapes, cherries, peaches and nectarines — are in 7A. (Note, these are Canadian zones. The U.S. system includes Canada but its numbering is different.)
•
Heat hits the capital in this 2012 file photo.
Climate change will be deadly
Take today’s annual mean temperature of 6.4 C. In the best of possible futures, it will still rise to 8.4 C by mid-century and stay there until 2100.
In a future with moderate pollution improvements it will rise to 8.9 C and then to 9.6 C late in the century. That’s more than three degrees of increase. It’s less than the worst case (a rise of 5.5 degrees) but still enough to cause trouble.
Most obviously, extra heat is bad for our health.
READ MORE: Age & health are big factors in heat wave deaths, study shows
More Canadians will die in a hotter climate. That’s a harsh statement, but a factual one. While it would be rash to predict numbers, it’s worth noting some proven trends.
For starters, Health Canada uses an analysis of the number of people who die in the city of Winnipeg, related to heat. They don’t count trauma deaths — vehicle accidents, falls, and so on.
Their conclusion: “At approximately 26°C/78.8°F excess mortality begins to increase as ambient temperatures increase; the increase in deaths becomes much more pronounced above 35°C/95°F.” (These are actual temperatures, not humidex.)
The City of Toronto’s public health department estimates that city has 120 deaths a year from heat.
Health Canada notes that “In 2010, Montreal experienced a heat event (July 5 – 11th) where there were 304 reported deaths from all causes in Montreal residents, of which 106 were heat-related.”
As a side note, cities are in a special category. They are known in the climate business as “urban heat islands” whose asphalt and concrete are hotter than rural areas nearby. Cities can be one to three degrees hotter in daytime. But the real difference comes at night. Because pavement and rooftops hold heat, they can be up to 12 degrees warmer at night than the greener countryside. Humidity increases this effect. It also makes the human body less able to lose heat by sweating, because a person is surrounded by moisture, and you’re basically trying to make sweat evaporate into a cloud.
It’s hard to count heat-related deaths, notes Martha Robinson of Ottawa Public Health, because in the emergency room it’s not clear who is suffering from heat alone and who has heart or respiratory trouble. Often, several factors are jointly to blame.
In August of 2003, a two-week heat wave killed more than 14,000 people in France — yes, really. Many cities reported reaching highs of 39 to 40 C during the hot spell, and temperatures throughout the country were mostly five to seven degrees above normal.
Many of those who died were elderly but fit enough be living alone, while the more frail of the elderly were in air-conditioned nursing homes or having someone oversee them.
Elderly people suffer more in heat because their bodies are less efficient at shedding heat. And brick and stone French buildings that are normally efficient at cooling overnight were unable to cool during the heat wave, because the nights stayed warm.
Thousands more died in other countries in Western Europe.
• In the 1995 Chicago heat wave there were 739 heat-related deaths in the city in five days. Most of the victims of the heat wave were elderly poor people, who did not have air conditioning.
• In a far less severe heat wave in Ottawa in 2010, with temperatures of 34 to 35 C for six days, Ottawa’s paramedics reported that the number of calls they received for all causes rose by 18 per cent.
READ MORE: Why humid is worse than hot
One-year-old Nayden cooled off at Lansdowne’s water plaza Sunday September 24, 2017.
Tough rows to hoe
Farming will be harder. Mainly, says the dean of the Ontario Agricultural College in Guelph, it will be more unpredictable, which is the same thing.
“We are less worried about the term global warming (than) global climate change,” said Rene Van Acker. “In agriculture what really worries us, and the insurance companies can bear this out, is the variation around the mean and the decreasing predictability of what the weather will do. Irma frightens us in agriculture because (Hurricane) Irma is an example of the increasing strength of storms that comes with changing climate.
Irma, the strongest Atlantic hurricane since 2005, caused enormous devastation across the Caribbean in early September.
“We know in agriculture that our crop failures are driven typically by too much water or not enough water. Variations around that, and more extremes, are a tremendous challenge for us.”
If it were just a case of a slow rise in temperature, this wouldn’t bother farmers. Seed companies are used to breeding new hybrids; they already produce a range of corn and soybeans, for instance, that are suited to warmer and cooler regions within Ontario.
“But we know it’s not that.”
Ellie Renaud at her farm east of Village of Frankville, Ont. She and other local farmers will face climate-change challenges in the years ahead, experts predict.
You’re less likely to travel along a highway beside a uniform cornfield that stretches for miles, and more likely to a patchwork of different crops as farmers diversify their crops to diffuse the risk. Hybrid crops that are more drought resistant are also likely.
But you may also see crops that exist today only in the lab. One example: Perennial grains.
Today a farmer must plant corn, wheat and other grains every year. But there are prototypes of perennial cash crops — wheat and flax in particular — that offer the hope of more sustainable farming.
“Not that we would shift everything to perennials but we might want a short-term perennial in our rotation, Van Acker said.
“Those crops will respond differently to an extreme year than an annual crop,” he said.
Perennial plants have deeper roots than annual plants. “It is growing in the ‘shoulders’ of the season — early spring and late fall. It has a fundamentally different resilience” to insect pests.
“It tends to be more tolerant of both drought and excess water,” likely due to the more developed root structure.
If a perennial crop grows for several years in a row and is then replaced by another crop in a scheduled rotation, it even helps the new crop, because the perennial often keeps weeds in check.
Van Acker learned this as an undergraduate. He had a summer job selling herbicides and found dairy farmers were a tough sell: They grew alfalfa for three or four years as part of their rotation. It is a perennial “and alfalfa can do a lot to decrease your weed population. So the annuals they would plant after those alfalfa crops would almost not need herbicide. It’s just one example, but crop rotation is a fundamental tool for all kinds of problems we face.”
The impact means a less stable food supply and higher insurance costs for farmers. If crops fail more often, or if some crops become to undependable to plant in the first place, Canada becomes more dependant on imported food, and an important sector of our economy loses strength.
READ MORE: Rainy summer a ‘disaster’ for local farmers
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Residents of Parc de la Riviera in Gatineau had to be evacuated after a rainfall washed out the streets.
Get ready for more flooding
Rivers will flow faster at times, more slowly at others.
The Mississippi Valley Conservation Authority is in luck. Back in the early 1900s, someone had the bright idea of measuring the flow of the Mississippi River at Appleton, and the records provide a century-long data set that is rare in this country.
The conservation authority feels that the pattern that is well established from all these years of data is going to change.
The spring runoff will start a couple of weeks earlier, in the future.
Hotter weather means that even with a rainier future our streams and rivers will flow even more slowly in late summer and early fall than they do today.
But by late fall the authority is expecting a surge upward in river flows, a result of two changes: more precipitation falling than today, and more of it falling as rain rather than snow once December arrives. The more extreme highs and lows in river flows mean bigger swings in water levels — greater chances of flooding in spring, and of water shortages in summer.
And more rains mean more floods. In late October, when floods once again swept through the Outaouais, Gatineau Mayor Maxime Pedneaud-Jobin told a radio interviewer flatly: “Our infrastructure isn’t designed for this.”
And he said he expects heavy downpours more often in future years.
The mayor of Chelsea, Caryl Green, says it’s time for municipalities to start building bigger culverts to prevent road washouts that seem to be increasing in frequency.
Algae photographed on Upper Rideau Lake in this file photo.
Algae and the affect on our lakes
The Rideau Lakes and others like them may look the same on top in 50 years, give or take some changing water levels as the lakes adjust to both greater rainfall and more evaporation.
The real change will be evident deeper down.
“One of the first things you’ll see is we are going to have less ice cover,” says John Smol of Queen’s University. He studies change in Eastern and Arctic lakes, and also studies lake sediments, which preserve the record of climates since the last Ice Age in the single-celled fossilized organisms that become more or less common as environmental conditions change.
“The easiest way to describe it is the summer is getting longer. That’s partly because of decreased ice cover, partly because ice comes off earlier,” he said.
Lakes are already showing hints of what is to come. They are forming layers that last longer, and these have an effect on what lives in the lakes, especially algae.
“Deeper lakes stratify into three layers,” Smol explains. “If you are ever treading water and suddenly your toes feel cold, that is because you have got into the deeper, cold water. Cold water is denser, warm water is less dense.”
They form distinct layers that do not mix, like a cocktail with different coloured liqueurs in layers (an effect that is also caused by differences in density.)
“You have isolated the lake into three sections much longer than you used to, even weeks longer. Blue-green algae really like it hot. And they do better under stratified (layered) unmixed water.” They also have a longer growing season if the ice cover doesn’t last as long, because there’s a longer period of sunlight shining into the water. Algae are plants and they use photosynthesis to get energy.
“So I think (this is) one of the reasons why we are seeing all these algal blooms, especially in August. … The blue-green algae can also form toxins for humans and other organisms.”
Another problem: starving fish of oxygen.
“The longer you keep the lake stratified in those three layers, the more you start losing oxygen in the deep waters. It is not being recirculated with the air up above. So a lot of the fish people like, like lake trout — they are being more and more stressed.” Trout and salmon are cold-water fish but they do need oxygen. “So we may start losing some of our most prized fish. That’s something we are already seeing happening.”
“Episodic” weather — heavy rains that cause flooding, and droughts that dry up wetlands — will cause bigger swings in water levels than we are used to.
And even massive forest fires affect lakes, especially on shorelines.
“The climate is like a big threat multiplier,” Smol said. “Almost everything is worse under a warmer climate.”
There’s already data showing that Muskoka lakes have a shorter ice season.
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Green undergrowth is flourishing at the site of a forest fire near Moodie Drive in the summer of 2012.
Pining for the forest of old
At the University of Minnesota Center for Forest Ecology, Lee Frelich has concluded oaks and white pines will probably adapt well to climate change and that their populations may expand.
Beeches and red pines will not do as well.
“Oaks, through their evolutionary history, are well set up to take advantage of longer summers and more dry spells. They are drought-tolerant and they are able to use a six-or seven-month growing season a lot more efficiently than other tree species that you have there,” the veteran tree scientist says.
The white pine “can grow in a long summer or a short summer and it is very drought-tolerant.”
But his main point is that diseases and bugs that thrive on warmer temperatures, and also the increase risk of fires, are as much a threat to trees as the increased heat itself.
“There are just so many insect pests and diseases (in trees), you wouldn’t believe it. We have something like 471 of them that are present in North America now.”
He also points out that although trees can move farther north in a warmer climate, but they cannot adapt and move as fast as birds. Faced with a sudden and large-scale change in climate, he says, some forests will just die.
While his research is in Minnesota and Wisconsin, Frelich is also familiar with the forests of our region — an extension of the Great Lakes hardwood forests. He believes the future here will look a lot like what he studies at home.
“I think a lot of surprises are in store no matter how smart you are. A lot of surprises are in store.”
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A robin hunts for supper in Ottawa.
Expect some ruffled feathers
Most birds around Ottawa will likely adapt, in time.
Still, migration is already becoming a struggle for some birds, says Bridget Stutchbury of York University.
“There are tons of studies showing earlier nesting, especially in species like the robin who don’t migrate very far — or at all. So, for instance, robins can sense our earlier springs because they only go a short distance south. In migratory terms, they don’t really leave our neighbourhood. But species that fly all the way to South America are not expected to notice, and adapt, as spring begins earlier.
“One of the big questions in climate change for songbirds is how quickly the long-distance migrants can adapt to warmer springs,” she says.
Migrating birds have been slowly adapting since the end of the last ice age, and they are experts today at flying north when the time is right. This is crucial to their ability to eat: Insect eaters have to arrive in Canada when there are insects to catch, for instance.
“Eventually they will (adapt),” Stutchbury believes. “It may take a generation, or two or three or four. There will be some time lag,” she predicts.
But in our hotter future, you may see birds nesting at the wrong time, missing the food bonanza that will happen a few weeks earlier than it did way back in 2017.
“The idea that there is a peak season when you can feed your kids. The peak in food abundance occurs at a particular time and the birds would time their egg-laying so that their kids would hatch out during that peak. And some research in Europe shows that there is (today) a mismatch between the peak of food and peak demand on the birds’ part.
“That will affect reproductive success, productivity. They won’t producing as many kids as they could if they nested in the optimal time of year.
“We know that will self-correct over time,” because each species has some early birds and some late arrivals every year, and eventually the early birds will be the ones raising lots of babies. So in the long run, Stutchbury sees most of our local bird species learning to live with change, but they may go through tougher times until that happens.
You may also see new birds at your feeder, southern residents that are pushing northward as the cardinal already has. (The first cardinal in Ottawa was recorded in 1945.)
Northern mockingbirds may come to Ottawa, Stutchbury believes. So may hooded warblers, which today live only in the southern fringe of Ontario near Lake Erie. The mockingbird is a grey, slender extrovert with a big personality and all kinds of different calls and songs. The hooded warbler is a little black and yellow forest bird.
“When it comes to birds, the (climate) concern is really not so much the birds we have around here. It’s more the Arctic birds and seabirds,” she said.
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And so the view from Canada 200 is steamy, humid, but not without hope. Climate has never stayed completely stable, and humans have the ability to endure hardship and adapt to changing patterns of rainfall, terrible storms, changing conditions for agriculture, and waves of heat.
Today, since it seems unlikely that we will stop climate change, we can prepare for the next test of our ability to adapt to our changing Earth.
READ MORE: Will we never learn? Tom Spears looks at the hot air that abounds when politics meets greenhouse gasses
tspears@postmedia.com
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