Module: Climate change
How fast is Canada warming?
Canada’s annual average temperature has risen by about 2.5 °C since 1948, roughly twice the global rate. Warming is fastest in winter and in the North, which matters for permafrost, ice roads, fisheries, agriculture and wildfire.
- Trend since 1948
- +2.5°C
- +0.33 °C per decade
- 2024 departure
- +3.1°C
- Relative to 1961–1990
- Warmest years
- 2010, 2024, 2023
- +3.1 °C, +3.1 °C, +2.9 °C
- Last decade vs first
- +2.1°C
- Mean of 10 most recent vs 1948–1957
Year-to-year noise around a clear trend
Annual temperature departure from the 1961–1990 average, Canada
°C. Blue years were colder than the reference, red years warmer. The fitted trend is +0.33 °C per decade.
- Colder than 1961–1990
- Warmer than 1961–1990
- Linear trend
Winters are warming fastest
Warming by season, 1948–2024
Linear trend in seasonal mean temperature, °C over the full period.
Why economists care
Exercises
How many of the last 20 years were colder than the 1961–1990 average? Use the table view.
Check your reasoning
Count the negative departures from 2005 to 2024. In this series there are none: every year since 2005 is at or above the reference.
Download the CSV and fit departure = a + b × year in a spreadsheet or Python. Do you get the slope shown on the chart? Then fit it only for 1980 onwards. Is warming speeding up?
Show a hint
In Python: numpy.polyfit(years, departures, 1). The slope is in °C per year; multiply by 10 for per decade.
Check your reasoning
Over the full period the slope is about 0.33 °C per decade. Fitting from 1980 onward gives a steeper slope, which is consistent with acceleration, although a shorter window also has more uncertainty.
Why does the chart use departures from a reference period instead of absolute temperatures?
Check your reasoning
Departures (anomalies) remove the effect of where stations are located. A mountain station and a coastal station have very different absolute temperatures but similar anomalies, so anomalies can be averaged across the country meaningfully.
Pick one Canadian sector (northern transport, Prairie agriculture, or forestry). List one cost and one benefit of a warmer winter, and propose an adaptation investment with how you would evaluate it.
Check your reasoning
Example: northern transport. Cost: shorter ice-road seasons raise freight costs for remote communities. Benefit: longer ice-free shipping seasons. Adaptation: all-season roads, evaluated by comparing discounted construction and maintenance costs with avoided airfreight costs over the asset life.