Like a giant green scarf, the boreal forest embraces the globe. It's home to a cold but living, breathing community of plants, animals and humans. Marked by mountains, over a million lakes and other waterways, muskeg and human settlements, it sprawls over the vast expanse of the northern hemisphere. Every third tree on the planet (mostly evergreen) is found there, making it one of Earth's largest remaining ecosystems. One-half of this immense, wooded habitat is found in Russia. One third of it is here in Canada, where it occupies more than half of our entire land mass. The rest is shared by Alaska and Scandinavia.
Part of the "boreal plains" of western Canada. A PinP photo. |
An Important Gathering - an Ominous Conclusion
Every two or three years, the International Boreal Forestry Research Association (IBFRA) meets to assess the overall health of the region. Delegates include government and university specialists in various fields relating to forests such as fire, disease, insects and the changing climate. It’s an opportunity to pool valuable and diverse knowledge and recommend ways for policy-makers to proceed with overall forest management.
IBFRA’s most recent prognosis is sobering; the forest is “at risk.” It’s future - “highly uncertain.”
Wildfire in the Northwest Territories - Canada, 2014.
Along with the Arctic, the boreal is already at the epicentre of climate change. Concentrations of carbon dioxide, the most common greenhouse gas, increased in the region by one-half since 1960, a magnitude that has startled many scientists. While the planet’s entire surface temperature has risen .8 degrees Celsius since the 1870s, already a significant amount, the boreal region has warmed almost 4 times as much; 3 degrees C in that same period.
Up to 5 billions birds, like this Cape May warbler, nest in the boreal forest. In 2001, 85,000 migratory bird nests were lost to logging. (Source, Cdn. Geographic). |
A dramatic example of individual warming happened in July, 2013. That’s when parts of the Siberian forest were 16 degrees C above normal for a week.
But this pales in comparison to what might lie ahead. According to wide-ranging scenarios, the boreal could warm up another 4 to 9 degrees C above present levels before the end of the century. It all depends on the volume of greenhouse gases emitted by then. But this would not just be for a limited period like a week or so. This would represent an average, long-term increase that could become a "new normal” our great-grandchildren will have to endure!
A herd of bison, North America's largest land mammal in Riding Mountain National Park, Manitoba - where the boreal meets aspen parkland and fescue prairie. |
Summarising the IBFRA findings, Werner Kurz, Senior Researcher with the Canadian Forest Service says, simply to keep warming to the lower end of the range, human-produced greenhouse gases would need to peak in about a decade, then actually decline before 2100! In other words, more carbon would have to be removed from the atmosphere by then than we would be adding from all human sources.
“This would require heroic efforts and technological changes,” Dr. Kurz observes. “We’re not saying it’s impossible,” he adds, optimistically. “It would just require big efforts.”
Worsening wildfires could bring a transition of the forest to more broad leaf tree cover, even grassland. Photos by PinP. |
Paying the Price “as we speak.”
Drought conditions resulting from a warming climate have already led to increases in the extent of wildfires. Despite torrential rains and flooding elsewhere in Canada last year, several boreal regions of British Columbia and the Northwest Territories were like tinderboxes, suffering “infernos” which consumed 4.5 million hectares of woodlands, three times the national average.
Preliminary satellite data from Russia reveal, if anything, an even more alarming trend there. In 2012, fire consumed about 40 million hectares of Russian forest. That's 40 times as large as the area burned there in 1979!
In an e-mail, Dr. Kurz tells PinP, "In areas that are affected by increases in forest fires, and where communities exist" (whether they are First Nations villages, fishing or mining camps), "the risks from fire will increase."
But warming forests won't be all bad news, he adds. "In some areas, warming will enhance tree growth, but bring losses in other areas where fires and drought impacts increase. The net impacts of these opposing trends cannot yet be determined, but will vary across the many regions of the circumboreal forests."
Photos by PinP.
In an e-mail, Dr. Kurz tells PinP, "In areas that are affected by increases in forest fires, and where communities exist" (whether they are First Nations villages, fishing or mining camps), "the risks from fire will increase."
But warming forests won't be all bad news, he adds. "In some areas, warming will enhance tree growth, but bring losses in other areas where fires and drought impacts increase. The net impacts of these opposing trends cannot yet be determined, but will vary across the many regions of the circumboreal forests."
Large wild animals need sizeable tracts of wilderness to thrive. That wilderness is being increasingly divided by logging roads and seismic lines. |
The Carbon Bomb.
Even the ominous term, "carbon bomb" has crept into the usually understated scientific literature. And, for a reason. The peat bogs and permafrost which underlie the boreal regions (and the Arctic), contain one-third of Earth’s terrestrial (in-the-ground) carbon stocks, twice as much as that in the atmosphere.
And, they're melting!
This could release up to 250 billion more tonnes of carbon into the air by 2100, a huge amount that is not even taken into account in the current scientific modelling. This would surely be a “tipping point” beyond which all bets are off.
As Dr. Kurz puts it, “There is potential for terrestrial feed backs that are far greater than currently assumed. It is therefore critically important to understand how the global boreal forests will act, either as a net source (emitter) or net sink (absorber) of carbon in the future. The more carbon that is released from these old pools, the more these forests act as carbon sources; the greater mitigation efforts (those that reduce emissions, the root causes of climate change) will be required in all other sectors.”
Global Warming and the Mountain Pine Beetle.
What Will the Future Hold?
A section of the mountain boreal region in western Canada,
possibly showing early signs of pine beetle infection.
Warmer winters have already meant higher survival rates for highly destructive mountain pine beetles. Native to British Columbia, they swept through that province some two decades ago, killing about half of the province’s commercial pine trees, notably lodgepole and ponderosa. It was the worst outbreak ever recorded anywhere. Then, the bugs spread into Alberta to the east, decimating thousands of additional hectares there.
And, they're still on the move. It's estimated they have marched at least 400 kilometres to the north and the east in the past five years or so. The consensus is, “In the absence of control, (even) further range expansion is likely.”
Lower impacts are expected through Saskatchewan and Manitoba. But that news is cold comfort to those provinces. It is now known that the bugs can and have spread to jack pine, a more common species in the forests here.
A Government of Manitoba website notes, for example, that large sections of forests destroyed by the beetles in B.C., harvested and exported in salvage operations, may still be infested with live beetles. So there are fears of a similar “epidemic” here.
Increasing Human Activity Complicates the Boreal's Future,
Many parts of the boreal are experiencing ramped-up levels of industrial activity such as mining (for metals, minerals and peat moss), logging, oil sands extraction and power generation. (Even though the impact that a warming planet will have on our future ability to generate hydro-power is anyone's guess, the province of Manitoba, for example, is spending billions of dollars on new hydro transmission lines and generating stations.)
A waterfall in the Canadian Rockies. What will a changing climate do to it and the aquatic life it nurtures? |
David Kreutzweiser of Natural Resources Canada, refers to these activities as “environmental stresses,” which place unknown pressure on the vast water resources of the boreal and the biodiversity of the aquatic creatures they sustain.
This surely raises the question, might this increasing activity itself be an example of how our politicians are barging ahead, without even bothering to read the kind of scientific research so readily available to them? The conference was told many of them either can't understand the research or believe it has nothing to do with the issue at hand.
It’s a poorly-kept secret that many scientists feel frustrated with this kind of political response.
This frustration has not been helped by the actions of Stephen Harper's federal government government in recent years. It has fired many researchers while others have been forbidden to speak out about their work. So the wording of the final communique out of the IBFRA conference is, perhaps, understandable for its remarkable restraint.
In a practise called "slashing," trees growing on land wanted for agriculture, are bulldozed and burned, eating away at the edges of the boreal in central Manitoba. |
Where To From Here?
Phil Comeau of the University of Alberta's Department of Renewable Resources was a co-chair at the IBFRA conference. In an interview with PinP, Prof. Comeau puts it this way.
"It is already too late to stop change from happening, but if we can find effective ways to seriously reduce greenhouse gas emissions now, we may be able to reduce the level of long-term impacts. As one questioner put it: 'We are driving at breakneck speed towards the edge of a cliff, but we still may have a chance to avoid going over that clifcliff."
Muuch of the information for this article was gleaned from material published online by IBFRA and The Canadian Journal of Forest Research.
(Except where noted, all photos are by the author. )
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One top scientist has just warned that we are all "f*cked" if global warming releases gigantic amounts of methane gas from the arctic tundra. The UN knows this is one of several catastrophic climate threats we're facing, and is bringing world leaders to New York for a major summit on this global emergency.
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