Keyword Climate models

Climate and weather are intimately connected. As the climate around us changes, it will have a dramatic impact on the weather. But if we try to understand climate on the basis of how we think about weather, it’s easy to misinterpret the science and underestimate the risks of climate change.

Roy McLaren has a lifetime of farming experience: he’s farmed in southwest Manitoba for over 70 years. He looks at the Climate Atlas maps of climate projections with concern. “That is pretty bad,” he says, looking at maps showing a huge increase in very hot weather. “With that kind of heat,” McLaren muses, “we’d have to change our farming methods. We’d have to adopt new crops.”

The most powerful computers on Earth are used to run climate models. Scientists use these models to understand how Earth’s climate works and to make predictions about how it might change in the future.

Earth’s atmosphere is made up of many different gases, some of which are “greenhouse” gases. They are called that because they effectively act like a greenhouse or a layer of insulation for Earth: they trap heat and warm the planet. For the past couple of hundred years, human activities (such as burning coal to generate electricity and fuelling our vehicles with gas and diesel) have been changing the atmosphere by adding a huge volume of greenhouse gases. This has caused the greenhouse effect to become stronger, and is making the planet warmer.

Earth’s climate has changed many times and many ways. We know a lot about the natural causes and effects of ancient climate change, and this knowledge helps us state with confidence that modern climate change is a product of human activity.

Weather records from across Canada show that every year since 1998—that’s 20 years ago now—has been warmer than the 20th century average [1]. This means that a whole generation of Canadians has never experienced what most of modern history considered a “normal” Canadian climate. But it’s not just Canada, of course. The whole planet is getting warmer.