Estimated Read Time: 5 minutes 30 seconds
Welcome to the High Lonely
Where the trees end and the tundra begins is where life gets simple and the climate gets complicated.
If you look at a map of the Robson Valley, you’ll notice it covered with arbitrary lines – town limits, park borders, highways and railways.
Guess which of those lines is understood by all of nature? Zero. They’re all human constructs.
But there is one line on a map that is comprehensible to all life: the tree line.
Okay, technically it’s not a hard line – it’s a transition zone between the sub-alpine and the alpine eco-regions and the correct wording will earn you bonus points during Wednesday Night Science Trivia Hour. But the point remains: all life – whether human, plant, fungi or animal – understands there is a place where the trees end.
(Okay, technically, trees don’t suddenly stop either, they just shrink to scrubby shrubs, which technically are trees, but, well, they don’t look like trees – they look like shrubs. Anyway, you get the gist.)
In Canada, we mostly think of the tree line as the place where the boreal forest ends and the arctic tundra begins – the vast, barren land where permafrost and caribou reign supreme.
And while that’s true, the tundra also exists right here in Mount Robson.
The high lonely – the area above it all in mountain landscapes like this one – is no different from the arctic, minus the location and plus a few metres.
You see, when our landscape gains elevation, the temperature drops and mimics the same conditions you find in the north: a cold, cold desert.
And like a desert, only the heartiest of creatures can survive and that’s why the alpine tundra matters: it’s our best barometer of the limitations of life on Earth and a bellwether for our climate.
Covering 3% of the Earth’s land surface, the alpine tundra generally starts where you’d find snow even on the warmest day in July – the 1950 metre mark of Mount Robson.
Why?
Tree cells struggle to reproduce below seven degrees Celsius and even the ‘tree’ shrubs that do grow here, usually just grow on one side because the fierce winds stunt growth on the other.
The result? A landscape that can resemble the moon – a place carved by the Robson, Berg, Bennington, Scarp and other glaciers and seemingly only loved by wolverines.
But underneath the lichen and permafrost are over 10,000 types of microorganisms that live in the soil – bacteria and fungi that ensure there is life above the trees; bacteria and fungi that store 90% of this eco-region’s carbon.
So even here, nature is working to help us.
That’s the
good news.
The better
news?
As the climate warms, the high alpine warms the fastest and this formidable landscape is becoming increasingly fertile ground for new plant species.
In fact, some studies suggest that by the year 2100, the high lonely won’t be that lonely – more and more species will be able to adapt and thrive at current alpine tundra elevations and some will be able to survive 600 metres higher than where organisms are currently found.
Here’s the not-so-great news:
Soil isn’t a speedy adapter to massive change – and for soil, our climate is changing rapidly. That means it will take centuries before soil will be created from the rocks in the landscape above the today’s high alpine.
Who cares, it’s just soil, right?
Wrong.
Even though more species – like carbon storing plants – will take root in the high alpine, the changing temperatures will cause existing soil to release the carbon it’s currently holding. And because new carbon-capturing, higher-elevation soil will take centuries to form, studies suggest no matter how many new plants take root, it won’t off-set the carbon released from the melting permafrost.
Then there is the weather itself.
Mount Robson is tall enough to create its own weather and as the climate changes and glaciers retreat and snow becomes rain at higher elevations, the physical landscape will morph.
Not overnight, of course, but increased weathering of sedimentary rock mountains, like Mount Robson, will put more sediment into the rivers that start here – like the Fraser.
That might mean more mineral-rich, fertile land down river and more vegetation on hillsides to armour it from the weather.
It also might mean increased flooding and increased droughts for those down river, due to changing hillside hydraulics and a smaller winter snowpack that will melt faster.
Almost certainly, it will change the types of eco-regions found in Mount Robson – and that means different species will have to adapt to changing habitats.
In fairness, all wildlife has evolved within the habitats they’re found. And most species can adapt and evolve as those habitats change again.
But, once more, the issue is the speed of change: Some species will be able to adapt to a friendlier high alpine and others will be pushed to the brink.
White-tailed ptarmigan, for example, base their nesting on the weather. In Rocky Mountain National Park in the US, studies have proven that chicks are now hatching 12 days earlier than they were a half-century ago. Which doesn’t seem like a big deal until you consider the insects they eat don’t hatch based on the weather. As these two events become more spread out, there is the risk of ptarmigan young starving and the population declining, leading to an infestation of insects. And if you know something about the pine beetle, you know how that story ends.
Which is not to say it will end poorly, it’s just that when we upset the delicate balance of biodiversity, we begin to lose the fail-safe mechanisms that give us a margin for error.
So, will the caribou suddenly find more lichen and more area to search for lichen in an expanded high alpine? Or will the high alpine eco-regions become too fragmented and make the caribou too vulnerable to predation as they navigate from one area to the next?
Will wolverines quickly learn to move to the new high alpine? Or will their food sources not evolve as quickly as the wolverine, forcing them into more conflicts with grizzlies and other predators for a shrinking slice of the prey pie?
