John Smol, a leading lake expert and pioneer of the field of “paleolimnology” looks at core samples pulled up out of deep lake sediments and can pinpoint environmental shifts over the course of millennia. A Fellow and medallist of The Royal Canadian Geographical Society, Queen’s University biologist and Canada Research Chair in Environmental Change, his decades of fieldwork in bodies of water across the Arctic and much of the world have helped teach us much about the realities of climate change. Here, he talks to Canadian Geographic about the potential designation of a new epoch on the Geologic Time Scale, one tied to humanity’s permanent influence on the Earth and its natural systems — the Anthropocene.
On declaring a new epoch
Well, whenever you get international in scope, things tend not to go fast — I can tell you that. But I think there’s a lot of pressure on the [committees of the International Union of Geological Sciences] to decide on a date. There are people whose job it is to argue about where those lines are drawn — as in, exactly how long the Cretaceous is or where the Precambrian ends.
Part of the pressure to agree on a date may be coming from the fact that there are already whole scientific journals named for the Anthropocene and numerous other references to the period out there. Scientists — and other people, for that matter — are going to start using it, official or not. And that can cause problems too. Otherwise you could end up with a widely accepted date simply through use, the way words become officially acceptable or change because of common usage.
On the timing of the new epoch
They’re getting close to defining this. The 1940s are coming out as a probable time for this official designation because of nuclear weapons testing and other post-war changes. You can actually clearly track when cesium 137 — completely human-made isotopes — started appearing. I had originally thought the Anthropocene’s start date would be the 1850s, because we certainly see widespread human impacts by then [related to stages in the Industrial Revolution]. But what’s really important is just acknowledging how much humans have changed things, and how rapidly.
On impacts of the Anthropocene in Canada
Well, there’s pretty well nothing we haven’t contributed to! If you look at the list of 10 or 15 things most people talk about in relation to major human impacts, we’ve got them all. Think about it: exotic species, species extinction and extirpation, over-fertilization of lakes and other water bodies, plastics in the environment and new chemicals being released, unalterably disrupted bio-geochemical cycles and so on. The ocean acidification we’re monitoring, for example, is directly linked to carbon dioxide emissions, and the food web is falling apart because of small changes in pH due to release of greenhouse gases. That alone means billions of dollars of potential protein disappearing.
On the evidence he’s seeing in the field
In my 30 years studying in the North the most striking is the fact that my research sites, these Arctic lakes and ponds, are evaporating away. We know from the paleo-record that they’ve been there for thousands of years, and because it’s so much warmer there now, they just evaporated away, and in the last 10 years. They are no longer “permanent.”
The Arctic in general is a good place to study these changes. It’s a relatively clean page and you can actually see things more clearly. But bear in mind that what’s happening there is also happening down in southern Ontario, and everywhere else, too.
On how this effects the rest of us
It’s a good question. Because while it’s ostensibly happening so scientists can divide the history of time, it is actually an acknowledgement that humans are the dominant forces on this planet — and not in a positive way. There are still many out there who say “Climate change is a natural process,” and it’s time to give up on that. The climate change we are experiencing is not natural. Natural processes are occurring, but we must acknowledge that humans are dominating many of those processes. We must acknowledge that we are the problem and therefore could be the solution as well.
It’s not simply practical, either. What defined the Holocene [the current epoch] have changed. It was the epoch during which the Earth was coming out of glaciation. We’ve overtaken that period, to the point that by now our climate should be getting colder. But because of greenhouse gases, it isn’t. Think about it — we’ve learned to change the physics and chemistry of the atmosphere of our planet, let alone of our water and soil.