Climate Change

What is it?

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Climate change is the long-lasting alteration of the global climate. While the process may occur naturally, the current changes are chiefly due to human activity. The average global temperature increased by 0.74°C in the past 100 years (essentially in the years following the industrial revolution). The northern hemisphere is now considerably warmer than in any other period in the last millennium. In addition, eleven of the past twelve years (1995-2006) posted the highest temperatures recorded since 1850.

What causes climate change?

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Scientists have advanced that the main cause of climate change, the greenhouse effect, is a natural phenomenon that is accelerated by human activity. The greenhouse gases (GHGs) released into the atmosphere increase the effect’s potential to capture heat (greenhouse effect), leading to higher global temperatures. Today, the atmosphere contains 32% more carbon dioxide (CO2)—one of the major GHGs—than it did at the start of the industrial age. This is largely attributable to the combustion of fossil fuels such as coal, oil and gas. Deforestation and intensive modern agricultural methods also contribute to the problem.

What are greenhouse gas emissions?

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Greenhouse gases (GHG) are atmospheric gases that have the ability to trap the sun’s heat and warm the surface of the earth. The presence of a certain amount of these gases make the earth habitable, since it would otherwise be covered in ice. However, human activity has dramatically increased the concentration of certain greenhouse gases, like carbon dioxide, by releasing additional carbon that was previously stored in the ground as coal or unrefined oil.
The result is global warming. The Kyoto Protocol attempts to avert harmful climate change by creating a framework for the international regulation of the six most important greenhouse gases resulting from human activity: carbon dioxide, methane, nitrous oxide, hydrofluorocarbons (HFCs), perfluorocarbons, (PFCs) and sulphur hexafluoride.

What are the effects?

Even a small increase in the earth’s average global temperature (0.74°C) has already had significant impacts.

Arctic and Antarctic
In the Arctic and Antarctic, warmer than average temperatures have led to the acceleration of the melting rates of permafrost and polar ice sheets. Northern peoples and animals are already dealing with major problems—houses with foundations built on once-solid permafrost are collapsing, the number of days per year that there is sufficient freezing to allow vehicle travel on ice roads is shrinking, and the disappearance of sea ice is forcing polar bears to swim long distances in open water to catch their food.
In British Columbia, slightly warmer winters and hotter and drier summers have created ideal conditions for the mountain pine beetle. The result is the devastation of the interior forests. Currently, 9.2 million hectares are affected, and the beetles are moving into Alberta. This has important consequences for natural biodiversity and the communities that are dependent on these forests as a source of income.
The oceans are warming and becoming more acidic, absorbing both heat and carbon dioxide, which transforms into carbonic acid. Degraded coral reefs in the Caribbean and off the coast of Australia mean reduced marine biodiversity and economic losses for fisheries and tourism.
Extreme and unusual weather events are becoming more and more common: the droughts in Australia, lack of snow in the Alps and central Canada in the winter and more intense tropical storms and hurricanes are just a few examples.
Act now
As global warming increases, the impacts will become more acute. It is important to understand that even a rise of a few degrees in the average global temperature will have a dramatic effect on the earth’s climate, triggering unpredictable feedback cycles and processes that will likely be far more impactful than what has been observed to date.