Canada’s Changing Climate Report (CCCR)
Scientists from Environment and Climate Change Canada, Fisheries and Oceans Canada and Natural Resources Canada, and university experts collaborated to produce Canada’s Changing Climate Report (CCCR). Released at the beginning of April, this report is about why Canada’s climate has changed, how it is changing, and what changes the future holds. This document is the first of a series to be released as part of a National Assessment to look at the impacts of climate change on Canadians and possible adaptation measures. It covers changes across Canada in temperature, precipitation, climate extremes, snow, ice, permafrost, freshwater availability, and sea level and other changes to our oceans.
This report quickly made headlines with the news that Canada is, on average, warming twice as fast as the global average. Canada’s North is one of the fastest warming regions on the planet, seeing an average temperature rise of 2.3°C since 1948, bringing the national average to approximately 1.7°C (since 1948). The report tells us that future warming in Canada will continue to be about double the magnitude of global warming, with the human factor the dominant contribution to this change.
To keep future warming as low as possible (for example, following the low emission scenario known as RCP2.6) the report highlights that global greenhouse gas emissions need to peak almost immediately, and that rapid and deep reductions in these emissions must follow.
In regards to precipitation, the report notes that in general, because of warming, there has been a shift to more rain and less snow, with observations indicating that Canada’s annual precipitation has increased since 1948. This trend is expected to continue.
As for climate extremes, warming means that heat extremes will become more severe, while cold extremes will lessen. In the future, heat extremes will become more frequent and intense, resulting in a risk of increased drought and wildfires. Alongside these predictions of increased drought extremes, there is a prediction that more intense rainfall events will increase the potential for urban flooding.
The authors state that observed changes in snow and ice in Canada are consistent with a warming climate, with a decrease in fall and spring snow cover and summer sea ice extent, and a warming of permafrost. These trends are expected to continue. Glaciers are also thinning, and it is estimated that even under a medium emissions scenario, most small ice caps and ice shelves in the Canadian Arctic will disappear by 2100.
Freshwater supply is also threatened, as the changing seasonal availability of freshwater means an increased risk of water supply shortages in summer.
Canada’s adjacent oceans have warmed, and are projected to continue to warm. They have also become more acidic, and less oxygenated. The authors give a very clear warning about the risk here:
“Ocean warming and loss of oxygen will intensify with further emissions of all greenhouse gases, whereas ocean acidification will increase in response to additional carbon dioxide emissions. These changes threaten the health of marine ecosystems.”
Local sea-level rise is also going to increase the risk of coastal flooding as sea level is projected to continue to rise along many of our coastlines, increasing the frequency and magnitude of extreme high water-level events. In some areas, Hudson Bay for example, the land is uplifting faster than the global sea level is rising and therefore in these areas the local sea level is projected to fall.
The report concludes with a chapter on our future, and the fact that the choices we make right now will directly impact the extent of climate change.
“The rate and magnitude of climate change under high versus low emission scenarios project two very different futures for Canada…Beyond the next few decades, the largest uncertainty about the magnitude of future climate change is rooted in uncertainty about human behaviour…”
CMOS commends the work of Canada’s research community in bringing the kind of high quality and rigorous scientific information embodied in this report to the attention of Canadians. We believe that this and upcoming reports will benefit Canada’s decision makers and its broader public, at all levels and in all regions. Such reports make us aware of the present and ongoing risks associated with climate change, the need to adapt to anticipated climate change and the timescales involved, and the importance of rapid action using, for example, the Pan-Canadian Framework on Clean Growth and Climate Change, to reduce greenhouse gas emissions and do our part to mitigate the most dangerous impacts of climate change.
Comments on the Report from our Experts
“The CCCR 2019 report presents a careful and detailed assessment of past and future climate across Canada. The main messages from this report tie in closely with the picture of a warming global climate, and with the picture of climate change over North America, that has been presented by the Intergovernmental Panel on Climate Change (IPCC) in their series of five comprehensive assessment reports since the 1990s. However, what is novel in the CCCR 2019 is the central focus on Canada, and the integrative assessment of projected changes in extreme weather, mean climate, freshwater resources and Canada’s ocean waters.
From my own research perspective, the projections for snow and ice are very closely aligned with work that I was involved with from the Canadian Sea Ice and Snow Evolution (CanSISE) network. That network concluded that Canada is likely to experience significant, and accelerating, changes to its cryosphere over the coming century. CanSISE also evaluated Canada’s earth system model (CanESM2), and concluded that the model does a very good job when compared with other models from its generation, and therefore Canada is in a strong position scientifically to make progress on quantifying changes in snow and ice.”
– Dr. Chris Fletcher, Climate modelling and analysis group, Department of Geography and Environmental Management, University of Waterloo
“Although I am more involved with weather prediction research and development, interactions and collaborations with climate change experts over the decades have convinced me that human induced climate change is serious and requires national and international cooperation. This report highlights that we need open, democratic discussion and decisive action as we wrestle with the accelerating changes that face us within Canada and globally.”
– Dr. Hal Ritchie, Meteorological Research Division, Environment and Climate Change Canada (ECCC)
“This report highlights the ongoing changes and concerns in ocean chemistry, and thus how ocean acidification may be a major issue in the waters around Canada in the near future.
With rising sea level, it also highlights that where there will be relative sea level rise (e.g. Beaufort in the Arctic and much of the Atlantic and Pacific coasts), this higher baseline combined with increased likelihood of major storms will mean the frequency and magnitude of extreme high water level events will increase.”
– Dr Paul Myers, Dept. of Earth and Atmospheric Sciences, University of Alberta, and Chair of the Canadian National Committee for the Scientific Committee on Oceanic Research (CNC-SCOR)
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Canada’s Changing Climate Report, CCCR, climate change, ECCC, Pan-Canadian Framework