Every ecosystem depends on the equilibrium of the elements. A Vancouver Island rainforest, a perfect illustration of the natural balance of growth and decomposition, based on carbon... element 6 on the Periodic Table, element 1 in the laboratory of life. "All life as we know it on this planet is based on chemical compounds of carbon, and there's an immense amount of carbon involved in the living systems of this planet. This West Coast forest ecosystem is a perfect example of that." Dr. Mike Apps is a leading authority on the carbon cycle: "These trees, the forest floor, and all the dead materials lying on the forest floor contain an immense amount of carbon. All the vegetation that we see on the forest floor, that's composed of carbon, and below all of that there's the soil which also contains a lot of carbon."
Trees and plants use solar energy to absorb carbon dioxide as organic materials that are the building blocks for growth. When these organic tissues decompose or are burned, the energy is released, and the stored carbon is recycled. "The leaves take up the carbon, but most of it is released back to the atmosphere, and that's done at the individual plant level and at the whole ecosystem level. So, we have a process where carbon is coming in from the atmosphere as carbon dioxide, being embedded in the tissues of forest ecosystems and other living systems for a while, but then released back to the atmosphere over time. We have, therefore, a continuous flow of carbon from the atmosphere, through the living system, back to the atmosphere."
For at least the last 450 thousand years that cycle remained fairly stable. But by the end of the 19 th century the balance had begun to shift, and as we moved into the 21 st century, there was over 30% more carbon in Earth's atmosphere than there should have been. And it's increasing at an unprecedented rate.
Dr. Apps explains: "Where's this extra carbon coming from? It's not because the plants are breathing out more. The primary cause is, in fact, our use of fossil fuel. We're burning fossil fuel, and when we burn fossil fuel we introduce new carbon dioxide into this active carbon cycle." Each carbon atom combines with 2 oxygen molecules to form carbon dioxide. This CO 2 then becomes part of a thin blanket of gases which help hold the Sun's heat in our atmosphere. It's called the Greenhouse Effect.
In a new report published in the scientific journal, Nature, researchers with the Smithsonian Tropical Research Institute have found that these rising levels of carbon dioxide are fertilizing the Amazon rainforests and increasing competition for light, water and soil nutrients, meaning that while the growth of large trees has increased over the past 20 years, the growth of smaller ones has slowed. This could change the fragile balance of rainforest ecology which in turn could affect rare species of wild animals and plants. Similar effects are expected in other forests, including those of Canada . Dr Apps points out, however, that for Canada 's forests, the changes in climate are expected to have a far greater effect. "We may already be seeing some of those effects in the increased fires and insect outbreaks that have plagued our forests in the last few years", he said.
We didn't set out to upset Earth's climate when we began burning coal for warmth, and oil for power. But one fact is clear... carbon dioxide, the main byproduct of industrial progress, is causing the heat that's driving the changes we're seeing.
"The amount of fossil fuel that we burn every year releases something over 6 gigatons of carbon as carbon dioxide into the atmosphere. Just to put it in perspective, that's equivalent to burning every tree in Canada , completely, every two years."
Rainfall patterns are also shifting in the time of The Great Warming, and that means more and more of the trees of northern Europe , western Canada , and the United States are burning up, releasing more stored carbon and accelerating The Great Warming. It's not hard to imagine a future where crisis centers spend much of the year confronting forest fires, and managing the impact of drought and disease on our forests.
"Climate change is thought to be driven by increasing concentrations of greenhouse gases. The principle greenhouse gas of concern is carbon dioxide or CO2. Humans take in oxygen and exhale carbon dioxide. Trees on the other hand take in carbon dioxide and release oxygen. It's part of the magic that keeps the global ecosystem in balance."
Leaves also filter the air we breathe by removing dust and other particulates. Trees help conserve energy through cooling and wind reduction. They reduce runoff, act as noise buffers, and are important because we like trees around us because they make life more pleasant. They provide habitat for wildlife, and one UK study showed for example that a maple tree provided a home for 26 species of insects.
"We are now certain we are detecting climate change as a result of human activity. As scientists, we may feel good to see that our models work, but the implications are sobering. We cannot stop climate change quickly, as imbalances have created a momentum for change, but we must attempt to avert future disaster by reducing emissions and increasing carbon "sinks," those factors which draw carbon out of the atmosphere."
At 59, Mike says that his interest in science was awakened by a grade 9 science teacher who was describing a scientific process that he found 'weird but wonderful'. "It was so weird, I wanted to understand more!" he said. "I believe that it's critical to give challenges to kids and young people. This is what makes science fun as well as rewarding."
The second milestone in his life, happened 12 years ago, when he found himself in conflict with an unyielding and bureaucratic supervisor, and he realized that he wasn't happy with the direction his professional life was taking.
"You spend so much of your life working, you should really love what you're doing. I decided that from that point forward, work had to be fun, challenging, and mean something. The reward is not what you get paid, or whether you have pleased your supervisor, but getting to see your work making a real difference in people's lives, that's what it's all about."
While Dr. Apps agrees that we need to cut back on our individual use of energy and resources, he believes that we need to work together because the problems caused by global warming are problems with our global systems and the way society operates. "We need to have incentives for more fuel efficient vehicles, we need to encourage and fund better mass transit. We need sustained social marketing that changes the way we perceive ourselves in the world. And each one of us needs to get out and vote to ensure we have the best leaders and leadership for our social system."
At the turn of the last century, we still thought the world was infinite. However, today, humans already control more than one half of the world's natural resources, leaving little room for errors. If we make very small mistakes, these may evoke very big changes, and that moves us one step closer to a long fall off a steep cliff."
ow a senior research scientists with Natural Resources Canada, Canadian Forest Service at the Pacific forest Centre and an adjunct professor in forestry faculties at both the University of Alberta and Lakehead University, Dr. Mike Apps is one of the local heroes featured in The Great Warming, a three part documentary. The first episode will be broadcast on the Discovery Channel on Earth Day, 22 nd April 2004.