I’m currently in Cape Breton for a gathering to inter the ashes of some beloved family members. Along the route to get here, the ongoing drought in Eastern Canada was very apparent. The vegetation was faded and dry. There were big electronic banners across the Trans-Canada Highway through Nova Scotia announcing the total burn ban in effect with a $25,000 fine for violations.
Drought conditions in Eastern Ontario and the Ottawa Valley are considered severe right now. My good friend Bob Dobson reports that he has never seen the level of the Snake River, adjacent to his fifth generation family farm near Cobden, so low. Many of the Snake’s tributary creeks are dry. Other people are sharing similar observations.
The curious among us want to know what is causing these drought conditions.
A simplistic explanation, often tacked on to the bottom of news articles, says: “Cliimate change, driven by the burning of fossil fuels, has increased the likelihood and severity of drouught.” But is this the full story or only a small part of it?
It’s true that a warmer atmosphere causes higher rates of evaporation of moisture from the land, but putting the blame for drought on burning of fossil fuels leaves out a really big part of the story, the story of the “living climate” that has been touched on in previous Watershed Ways columns.
Greenhouse gases like carbon dioxide do trap heat, but they don’t cause heat. The sun’s rays are the source of heat and it really matters a lot what kind of surface the sun’s rays fall on at ground level. If they fall on a mature mixed forest or other healthy diverse plant life, much of the sunlight is absorbed by the plants and used to make carbohydrates and transpire water vapour. Transpired water vapour carries embodied heat high into the atmosphere where some of it can be released to outer space. Healthy forest ecosystems also seed clouds causing much of the transpired water vapour to fall back down as rain thus keeping moisture in the local area and replenishing groundwater.
Conversely, when the sun’s rays fall on surfaces that have been cleared of their natural healthy vegetation, the resulting heat builds up, heating man made surfaces and the ambient air making our environment hotter. This hotter air gets trapped by the greenhouse gas layer and warms the atmosphere. Human land use patterns of draining, paving, deforesting and ploughing have thus prevented the movement of heat to the upper atmosphere by plants and have interfered with local moisture cycling. They have also dried out the land and reduced its water-holding capacity leaving less water in watercourses, soil and aquifers.
Transpiration of water vapour and seeding of clouds by mature mixed forests is part of the cycling of water locally and around the planet in large and small water cycles. The scientists who study these water cycles suggest they are elegant and sophisticated mechanisms for regulating Earth’s climate that have developed over millions of years. Some scientists suggest that mature forests are intelligent and time their transpirations to maximize water retention and recycling.
These scientists are telling us that water cycles are broken. Too much of the Earth’s surface has been stripped of healthy mature forests and replaced with asphalt and monoculture plantations.*
They say we need to preserve all of the healthy, climate-regulating forests that we have left on Earth. We also need to distinguish between mature, climate-regulating forests and “tree plantations.” The latter simply do not have the same ability to regulate the climate and are more susceptible to forest fires and droughts.
If you’d like to know more about the complex ways that humans are causing drought and how we can reverse the trends, check out the recent interview with scientist Anastasia Makarieva on YouTube entitled “Why we need forests: their Vital Role in Climate Dynamics, Rain, and The Biotic Pump.” Another excellent source of information about the new science of the “Living Climate” is the substack called “The Climate Water Project.”
*According to Earth.org, more than 75 percent of the Earth’s land surface has been altered and degraded by human activities and nearly half of the world’s trees have been purposefully cleared by humans in the last 12,000 years
About the author: Lynn Jones is a founding member of the Ottawa River Institute, a non-profit, charitable organization based in the Ottawa Valley. ORI’s mission is to foster sustainable communities and ecological integrity in the Ottawa River watershed.
Photo submitted. This article was originally published in Watershed Ways (2025,Sept.)
Climate change is an undeniable fact. It must be viewed as a long range trend and not what is happening currently. What we experience daily and seasonally is weather and it is irregular enough to support both sides of the argument over climate change. Simply put, climate change has been ongoing since the early days of planet Earth. There ire sceptics who will debate rather or not human activities are contributing to this change in the form of accelerated global warming but there are historical records going back to when we began keeping such records that prove, beyond any reasonable doubt, that our planet is warming. We can debate the causes but not these facts. Given that human activities such as fossil fuel burning add greenhouse gasses add other nasty stuff to the air we breath, there are plenty of good reason to do less of it regardless of our politics.
Actually, the current drought in this region is part of a cycle recurring circa every 20 years and dominated by the “Bermuda High” sitting over the Atlantic Ocean between Mauritania and Virginia. It’s much stronger in summer and weakens in winter and its maximum strength varies from year to year depending on a variety of factors but every ca 20 years it will be quite strong for 2 to 3 years. It slowly rotates clockwise (looking down) and when it’s strong it pulls up dry desert air from northern Mexico and Arizona which gives us those very hot and very dry days in mid-Summer which can last for months at a time. The last such hot droughts in this area, which I can remember, were in 2003 to 2005, 1981-1983, and 1963-1965. However there is always a drought here in mid-Summer altho usually only from mid-June to mid-August. As the Bermuda High weakens it pulls up more humid air from the Gulf of Mexico which brings us our rain and sometimes in some years we get “hosed” with torrential rains and massive snowfalls. Total annual precipitation in this year is ca 850mm and this is surprisingly constant so watch out, we might get plenty of snow over the coming winter to offset the summer drought! The effects of forest transpiration and deforestation and global warming are also certainly important but these are complex phenomena which are slower acting:- our summer drought is part of a long-standing cycle which goes back thousands of years. One reason that historically pine-and-oak forests have dominated in this area has been their ability to cope with deep sandy soils and intermittent droughts and especially in mid-Summer. However, instead of just passively and abstracting talking about trees it would be more useful to go out and plant a few in your spare time although the traditional tree-planting methods leave much to be desired:- those 6’x6′ red pine plantations are (ahem) a bit idiotic:- visit the federal forest-research station near Petawawa just off Hwy 17 and you will find 14’x14′ works much better and actually randomized mixed plantings of red-oak and red-pine on a wide spacing would give very good results both in terms of eventual timber yield and aesthetics.