"Ask almost anybody if they think the climate's changed in the last couple of decades and they will all say 'yes' and give you lots of examples." James Lovelock
Most Albertans recall our parents or grandparents telling stories about the weather that start with, "when I was your age..." These stories often included tales of snow banks up to the eaves or having to walk mile after mile in frigid temperatures to get to school or milk a cow. These anecdotes are certainly entertaining but, in order to truly understand climate change, we have to rely on science.
Scientists first observed long term changes in temperature, precipitation (e.g. rain and snow fall), and wind in the mid 1800's (see Keeping Our Cool p.72). Since then, scientists have asked how our climate is changing, what the impacts of climate change are and what is responsible for these changes. Globally, we are asking what we can do to avoid some of these harmful impacts.
Climate change is a long term shift in global weather patterns. Historically, various natural factors such as changes in the Earth's orbit, solar output, volcanic activity and/or variations in ocean currents have changed the Earth's climate. We are still coming out of an ice age, during which most of Alberta was buried underneath a sheet of ice. In other words, the only thing constant about the Earth's climate is that it changes.
From: Natural Resources Canada Source: United Nations Environment Programme. GRID-Arendal. Vital Climate Graphics. ISBN: 8277010095.
While the global climate is naturally variable, the problem is that the current climate is changing at a historically unprecedented rate. If we had millennia to adapt to these changes, we would potentially be able to so with relative ease. Unfortunately, we do not. A study from the National Oceanic and Atmospheric Administration reports that "climate change that takes place due to increases in carbon dioxide concentrations is largely irreversible for 1,000 years after emissions stop." This means that we cannot stall in limiting the amount of carbon dioxide that we release into the atmosphere. We have to change our behaviours and we have to do it soon.
In this guide:
