By Terri-Lee Reid
It seems as though people use the terms climate change and global warming interchangeably these days. But they’re not quite the same thing. It’s time to clear the air!
What is Climate Change?
Climate change is a long-term shift in weather conditions that includes changes in precipitation, winds and temperature. While a global problem, climate change impacts can vary from one region to another. One place may be having heavy rainstorms whereas another place could be experiencing severe drought. It could include melting glaciers, thawing permafrost, more intense storm patterns, rising sea levels, coastal flooding, ocean acidification, the freezing of lakes and rivers occurring later and thawing earlier and heat waves.
It is important not to confuse weather with climate. As already mentioned, climate change is a long-term shift or trend. Weather, in comparison, is what we see every day when we peer out our windows or step outside; a very short term event.
What is Global Warming?
Global warming, on the other hand, is the increase in the Earth’s average surface temperature and is attributed to an increase in greenhouse gases in the atmosphere – mostly caused by human activities. Greenhouse gases trap heat in the atmosphere, causing surface temperatures to be higher than they would normally be.
Over most of the Earth’s history, there have been ice ages and warm periods. However, these changes were a result of natural processes such as changes in the sun’s intensity, changes in the Earth’s orbit or the amount of volcanic activity. The warming that has been observed since the mid-20th century is highly linked to human influences and it is proceeding at an unprecedented rate.
Climate Change in Action
Climate change is already affecting many species in Canada. For instance:
- Tree swallows in North America are laying their eggs more than a week earlier than they used to. This could impact the survival of the young as insects may not yet be plentiful.
- Milder winters and warmer summers has caused Mountain Pine Beetles to expand well beyond their historic range, extending into northern British Columbia and into the boreal forest in north-central Alberta, killing millions of hectares of pine forests. Mountain Pine Beetles are not only killing Lodgepole Pines but now they are reproducing in Jack Pines.
- Different animal species are hybridizing, for example Northern Flying Squirrels and Southern Flying Squirrels.
- Black-legged Ticks that carry and transmit Lyme disease has expanded into southern and western Ontario as well as Manitoba, Quebec and the Maritime Provinces.