Global Warming Impacts Health

Climate change threatens to trigger a widespread and devastating health crisis in Canada. Why are medical professionals and policy-makers slow off the mark?

by Alex Roslin

Canadian Geographic

October 2010

[This article won a gold prize from the National Magazine Awards in the Editorial Package category and was a finalist for a second National Magazine Award in the Health & Medicine category.]

Monday, July 5, 2010, was the kind of sticky, pavement-shimmering Montréal day that only kids at a water park could appreciate. And that is just where 14-year-old Mathieu Thibodeau-Ross found himself, heading for the whitewater rafting ride at the Mont Saint-Sauveur Water Park, 75 kilometres northwest of Montréal.

The humidex was approaching 40°C a little after 11 a.m. when Mathieu started up the stairs to access the ride. He never made it to the top. Witnesses would later report that the teen started to wheeze and then collapsed. He was pronounced dead at the hospital, a victim of cardiac arrest.

It will likely take several months for the Quebec coroner’s office to determine what role the high heat and humidity may have played in Mathieu’s fate. But it is already clear that the number of deaths spiked to unusually high levels during the hot spell which began on that blazing July day. By Thursday, Environment Canada was calling it the most intense heat wave on record in Montréal. With thick smog blanketing the city all week, 80 people died in Montréal from various causes on that Thursday alone — double the typical daily total. ...

[Read the rest of this story here.]

Plenty to Carp About

CLIMATE FILES

Trying to hold the line against a big, hungry fish that would thrive in our ever-warmer waters

By Alex Roslin

Canadian Wildlife

May/June 2010

A highly invasive fish that could devastate the Great Lakes ecosystem has penetrated into Lake Michigan for the first time, and fish biologists say climate change will likely exacerbate its onslaught.

“It’s a potential knockout blow for the Great Lakes,” says Scott Parker, a Parks Canada biologist who monitors invasive species at the Fathom Five National Marine Park in Georgian Bay. “They’ll dominate (native species) and have a huge impact.”

The notorious Asian carp, a voracious plankton-eater sometimes called the aquatic vacuum cleaner, grows to 45 kilograms and consumes up to 40 per cent of its weight daily. It has already decimated the ecosystems of the Mississippi and Illinois rivers and their once-diverse fisheries. Carp, which are virtually worthless commercially, now make up 90 per cent of the fish caught in those rivers.

While a live Asian carp has yet to be found in Lake Michigan, a test used to detect the species’ DNA in water indicates a live fish was very likely present in the immediate area, says Jennifer Nalbone, an invasive species specialist at Great Lakes United, a joint Canada-U.S. environmental group. This despite the fact that American authorities put up an underwater electric barrier in April 2009 in the Chicago Sanitary and Ship Canal, the only link between the carp-infested Mississippi River and the Great Lakes, to prevent the species from reaching the Great Lakes.

Carp DNA was first detected beyond the barrier in August. In subsequent months, more of it was found further down the canal and in two rivers that drain into Lake Michigan. This past January, the DNA was detected in Chicago’s Calumet Harbor in the lake itself. [See the carp's progress on this map.]

The discoveries have set off panic among Canadian and U.S. fish scientists, environmentalists and the $7-billion Great Lakes fishery. In mid-February, the White House hosted a summit on ways to stop the carp invasion. And Michigan and Ontario authorities have gone to court to get the state of Illinois to block the canal. Illinois opposes the idea, saying it would hurt the state’s economy.

“The DNA evidence has certainly raised the sense of urgency,” says Nalbone, who faults authorities for not moving quickly enough and calls for a “very aggressive monitoring and eradication plan.”

Asian carp—a term that encompasses several invasive species of the fish such as bighead and silver carp—were imported to control nuisance algae in the southern states, but escaped into the Mississippi River during floods.

Apart from displacing native fish, silver carp are infamous for jumping out of the water when startled by watercraft [see video], something Becky Cudmore, a biologist and invasive species expert with the Fisheries and Oceans Canada, experienced first-hand when she and other carp scientists headed out on the Illinois River. Carp started flying out of water all around, some soaring as high as three metres and many landing in the boat.

One five-kilogram specimen smashed into Cudmore’s calf. “It left a good mark and numbed my leg for four hours,” she says. “It was very sobering. We really wouldn’t want them in Canada.”

Asian carp are a temperate-water fish, well suited to existing climactic conditions in the Great Lakes, even without global warming. But climate change will likely make the lakes even more susceptible to a carp invasion, says Bryan Neff, a biologist at the University of Western Ontario.

“Climate change can destabilize the natural ecosystem in the lakes and make it more susceptible to invaders,” he says. “The ability of a native ecosystem to repel invaders would diminish.”

With climate change, for example, Great Lakes water levels will likely fall, which could in turn “cause native species to become more sensitive and susceptible to invasive species,” Neff says.

Cudmore agrees. “Climate change will certainly help—not hinder—invasive species like the Asian carp.”

Alex Roslin is an award-winning journalist in Lac Brome, Qc., and writes a blog on investigative reporting at AlBloggedUp.Blogspot.com.

WARM UNWELCOME

Invasive species of wildlife and plants, which already cost $120 billion annually in the United States alone, are far more able to adapt to climate change than native species, a new study in the journal PLoS One says.

Two Harvard scientists studied plant-flowering data going back 150 years in Massachusetts, including information collected by conservationist Henry David Thoreau around the famed Walden Pond.

As the average temperature increased 2.4 degrees Celsius over this period, invasive plant species were able to advance their flowering time to be 11 days earlier than native species.

As a result, invasive species have significantly increased their population significantly more than native plants like lilies and orchids, with nearly two-thirds of the species Thoreau documented seeing sharp declines or disappeared.

“These results demonstrate for the first time that climate change likely plays a direct role in promoting non-native species success,” co-author and Harvard biologist Charles Davis told ScienceDaily.com.

Creeping Desert

Will climate change push fertile prairie to desolate wasteland?

By Alex Roslin
Canadian Wildlife, September/October 2009

Water is the lifeblood of the Canadian Prairies—essential for its ecosystems, drinking and economy. But water experts say life could be turned upside down there as climate change brings severe drought, dried-up rivers and near-desertification to the Prairies in coming decades. Some of the impacts are already well underway.

“There is going to be tremendous stress on ecosystems,” says James Byrne, chair of the geography department at the University of Lethbridge. “It’s going to require substantial adjustment.”

“There will be a fair amount of problems in terms of agricultural production,” says Suren Kulshreshtha, an agricultural economist at the University of Saskatchewan. Impacts could include a 10 to 30 per cent drop in crop yields across the Prairies, according to Environment Canada.

Temperatures across the Prairies have already gone up by between one and four degrees Celsius in the past century, depending on the region. By 2100, they’re expected to go up a further 6.5 degrees under a median climate-change forecast in a landmark study coauthored by University of Alberta biologist David Schindler in 2006. He found that temperatures in northern Fort McMurray will be warmer than they are now in Lethbridge, 1,000 kilometres to the south.

Warmer temperatures, in turn, are behind a few parallel trends that are combining to imperil the Prairie water supply: melting glaciers and diminishing snowpacks in the Rocky Mountains, and increased evaporation of soil moisture.

Some of the hardest hit glaciers are in Montana’s Glacier National Park, which also sprawls into British Columbia and Alberta. Ice fields there help feed the South Saskatchewan River, whose waters meander across the Prairies and ultimately drain into Lake Winnipeg. This watershed is the main source of freshwater in a vast expanse of the southern Prairies.

But high up in the Rockies, rising temperatures over the past century have slowly melted 67 per cent of Glacier National Park’s icesheet. Scientists from the U.S. Geological Survey now estimate the last glaciers there will disappear by 2020—a decade earlier than initial estimates because warming is happening faster than expected.

“All of a sudden the park needs to be renamed because there are no glaciers,” says Stefan Kienzle, a University of Lethbridge hydrologist who studies climate-change impacts in the Prairies and in the mountain headwaters of the region’s rivers. Kienzle worked with other leading Canadian scientists to coauthor a landmark review of those impacts for Natural Resources Canada in 2007. They concluded that rising temperatures will bring widespread drought to the Prairies, especially in late summer, and that there will also be more frequent severe droughts.

Many rivers and streams will dry up, and wildlife that depends on them will be devastated. “A large number of Prairie aquatic species are at risk of extirpation,” the review said.

Byrne, who was one of the lead authors of the study, says the Prairies will eventually turn into an arid tropical zone like Arizona, especially in summertime, with near-desert conditions in some areas. “Overall, the biggest concern is we’re going to see a big increase in variability (of the Prairie climate),” he says.

River flows in the three Prairie provinces are already down substantially. A severe drought in 2001 and 2002 caused an estimated $5.8-billion drop in Canada’s gross domestic product and 41,000 lost jobs, mostly in the Prairies. A study commissioned for Agriculture and Agri-Food Canada tied it to climate change and called for better preparedness to counter “the increasing threat of drought risk."

One of the key unanswered questions is the fate of the massive Columbia Icefield straddling the Alberta and B.C. border. This 365-metre-thick chain of glaciers is the largest mass of ice and snow in the Rockies and helps feed a watershed that spans the central and northern Prairies.

But this icefield is also retreating. One of its main components, the Saskatchewan Glacier, which is the primary water source for the North Saskatchewan River, has retreated 1.4 kilometres in the last 100 years. Another component, the Athabaska Glacier, has lost half its volume.

Low river flow in the late summer will have significant implications for wildlife in the watershed, says Kienzle. “It will put more stress on the ecosystem and on all species that depend on the rivers.”

LOW FLOW

Climate change is already affecting rivers in the Canadian Prairies. Summer river flows are 20 to 84 per cent lower than 100 years ago, according to a 2006 study coauthored by University of Alberta biologist David Schindler, which appeared in the Proceedings of the National Academy of Sciences.

“We were shocked by how extreme the changes in river flows had been,” a profile of Schindler in the journal quoted him saying. He added that the decline of Canada’s freshwater “might be the largest crisis facing that nation in the upcoming century,” the article said.