Question Period Note: Climate Science

Climate Science

• Environment and Climate Change Canada undertakes a comprehensive program of scientific research on the climate system and climate change.
• The science produced by the Climate Research Program provides the scientific basis for information to support adaptation and mitigation decision-making in Canada.
• Human activity is driving unprecedented changes in the earth’s climate, posing serious risks to the health and well-being of Canadians, communities, and the economy.
• Canada’s climate is warming twice as fast as the global average, with even larger warming in northern Canada.
• Climate change is affecting the frequency, duration, and intensity of many climate disasters around the world, like floods, wildfires, and droughts. A warmer climate will intensify some weather extremes in Canada.
• We all have a role to play in taking climate action. By working together, we can tackle climate change and protect the future of our kids and grandkids.

o Working with national and international partners, Environment and Climate Change Canada scientists generate and disseminate new knowledge and data to improve our understanding of climate system behaviour, the human influence on climate, future climate changes globally and in Canada, and associated impacts on natural and human systems.

o The scientific evidence is clear:
• Warming of the Earth’s climate system is unequivocal. Warming of Canada’s climate is also unequivocal and has been about double the magnitude of global warming, with even larger warming in northern Canada. This warming differential will continue with additional warming.
• The main cause of observed global warming is human emissions of Carbon dioxide (CO2) and other greenhouse gases (GHGs). This is also true for warming in Canada. This warming is effectively irreversible due to the long atmospheric lifetime of CO2 and inertia in the climate system.
• Additional emissions of GHGs will cause further warming and changes in all components of the climate system. Some additional emissions are inevitable; therefore, adaptation is imperative both to reduce the adverse effects of current warming and unavoidable future warming.
• Impacts of climate change are already observed and the severity and scale of future impacts, both on natural and human systems, are tied to the magnitude of future global warming. Adaptation can reduce the risks of climate change impacts, but there are limits to its effectiveness, especially with greater magnitudes and rates of climate change.
• Climate change is increasingly exacerbating the impact of other anthropogenic drivers (i.e., changes in land and sea use, direct exploitation of organisms), on nature and human well-being.
• To stabilize global temperature, global anthropogenic carbon emissions must become net zero (emissions and removals are balanced). The timing of ‘net zero’ depends on the global temperature target.
• The Paris Agreement commitment is to hold the increase in global average temperature to well below 2˚C above pre-industrial levels and pursue efforts to limit the temperature increase to 1.5˚C above pre-industrial levels recognizing this would significantly reduce the risks and impacts of climate change.
• Emission pathways that meet the global temperature target of the Paris Agreement of well below 2˚C, begin declining in the next few years and reach net zero global carbon emissions (‘carbon neutrality’) early in the second half of the century. Deep emission reductions in other GHGs (e.g. methane, nitrous oxide) are also required, as well as black carbon.
• All emission paths consistent with achieving low temperature targets require net negative carbon emissions in the second half of the century after reaching net zero carbon emissions. Negative emissions involve permanent removal of CO2 from the atmosphere, and are required to offset hard to mitigate emissions and to lower global temperature in the case of overshooting the temperature target.
• There are many opportunities to link mitigation, adaptation and the pursuit of other societal objectives through integrated responses.

o Changes specific to Canada’s climate are outlined in Canada’s Changing Climate Report, which was released in April 2019. Led by Environment and Climate Change Canada, Canada’s Changing Climate Report is a result of collaboration between ECCC, Fisheries and Ocean Canada, Natural Resources Canada, and Canadian university experts. Canada’s Changing Climate Report is national in scope and provides the Canadian context to the global issue of climate change. The findings are consistent with the broad international scientific understanding of climate change.

Question Period notes as provided by the Department to the Minister’s Office