One of the greatest damages of global warming is felt in the oceans, rivers and lakes, since the rise in temperature of the water itself damages the ecosystems. On the other hand, it is in the waters that many of the less-thought-of actions of human beings take place: dumping plastics or garbage in general into nature that then ends up in the oceans, thus affecting all aquatic fauna and flora.
Dr. Jesse C. Vermaire, Associate Professor Environmental Science & Geography and Environmental Studies at Carleton University, in Ottawa, has developed his work around studying the impact of climate change on freshwater streams and lakes, particularly here in Canada. He will help us understand what needs to be done urgently to try to stop the destruction of the planet.
Milénio Stadium: In recent times the world has observed a number of extreme weather phenomena. As a scientist who follows and studies the impact of climate change on freshwater courses, have the recent events of extreme floods (in central Europe, China and in England), and of rising air temperatures to unusual levels surprised you?
Dr. Jesse C. Vermaire: It is always shocking when you see these events but none of this is really surprising as these are the types of events that have been predicted to occur as a result of climate for some time now.
MS: Can we really say that everything the world has seen this year is a consequence of climate change or are there other reasons that could justify these phenomena?
JCV: Many of the extreme climate events we have witnessed this year are much more likely to occur under a warming climate and models have shown that some of them would have been unlikely to occur without recent warming. Of course, there have always been heatwaves and large storms but the frequency and intensity of these events are predicted to increasing with a warming planet and that is what we are seeing occur.
MS: In your area of study – how are the streams, rivers and lakes being affected with the phenomena we have seen? In Canada’s case, what impact are high temperatures, droughts and fires having on the course and quality of the water and its ecosystems?
JCV: For rivers and lakes in Canada floods and draughts definitely are a climate related impact we are seeing but we are also seeing some other surprising changes we are still working to understand. For example, warmer temperatures are increasing the length of the ice-free season in many Canadian lakes and this is increasing the length of thermal stratification in some deeper lakes. This longer growing season and change in the thermal stratification is promoting the growth of certain types of algae like cyanobacteria (blue-green algae) that can produce toxins that are dangerous to humans and other animals. To me this is one of the more alarming climate-related changes we are seeing in Canadian lakes.
MS: Are plastics, their overuse and lack of care in their post-life treatment (recycling), still one of the major sources of pollution of freshwater courses and consequently the sea? Now we might have to add masks as well…
JCV: Yes, for sure covid has increased the use of disposable products like masks but this is really just a small amount of the plastics we use. We need to reduce the amount of plastics that is making its way into our lakes, rivers, and oceans and this will involve reducing the use of single use plastics, improving recycling, and cleaning up litter all of which will be required to reduce plastic litter in our waterways.
MS: After so many years of the public concerns of scientists about the damage that humans have caused on Earth; after so many information campaigns about the need to change human behavior… Why are we still talking about plastics flooding rivers and oceans? What remains to be done?
JCV: I think that people have really only started to notice the amount of plastic that is ending up in our waterways and I have been very impressed on how people and government are taking action to help reduce some of these problems. Of course, there are many environmental problems that we need to address but I am an naturally optimist and there are examples where we have been moving in the right direction in conserving natural lands and reducing air pollution. In many cases, science has given us methods to understand environmental problems but sometimes implementing solutions can be slower for both technological and social reasons, but I am confident we are moving in the right direction, maybe just a little slower than is truly needed for problems like climate change.
MS: Nature has the magnificent power of renewal and even adaptation to new realities, but what could happen in the coming years if more drastic measures are not taken? And what measures need to be taken?
JCV: I think the two biggest measures we need to take is to reduce greenhouse gas emissions and conserve land to reduce biodiversity loss. Of course, climate change will impact all species but in many ways it is also a very human problem. Our actions are causing climate change and we will feel the pain of climate change most acutely when it impacts people, whether that is towns flooding or being endangered by wildfires or people struggling with heatwaves. Even in cities where we often feel removed from nature we will be impacted by climate change and it is important to take steps to reduce greenhouse gasses and mitigate these climate change impacts.