Report on the observed climate, projected climate, and projected biodiversity changes for Grasslands National Park of Canada under differing levels of warming

Grasslands National Park is among the bottom 39% of all non-marine protected areas, globally. All areas of the park will require substantial adaptation efforts, starting at 1.5°C. Averaged over the entire area of this park, with 4°C warming (global, above pre-industrial), the area is projected to remain climatically suitable for 42.2% of its terrestrial biodiversity (fungi, plants, invertebrates, and vertebrates), with none of its area remaining an overall refugia (remaining climatically suitable for >75% of the species) for biodiversity. If warming levels were held to 2°C, still none of the area would remain a climatic refugia and the area would remain climatically suitable for 66.5% of its terrestrial biodiversity. Even with warming levels of 1.5°C, only 12% of the area is a climatic refugia for biodiversity.

Between 1961-1990 and 1991-2020 the average monthly temperature has increased by -0.7° (October) - +1.9°C (January). With warming levels of 2.0°C the new average monthly temperature for May through October is equivalent to that only seen 1 in 3 years in 1961-1990, except for July having a new average temperature equivalent to that experienced 1 in 20 years. Five months have seen decreases in precipitation (December-January, August-September, and March) with the rest seeing increases. Models project that all months except July-September will become wetter. The combination of wetter winters, with warmer and drier summers suggests an increase in fire risk. The number of months classified as being in severe drought have decreased between 1961-1990 and 1986-2015. Under the climate change scenarios examined, the number of months in severe drought are projected to increase substantially (doubling by 2°C) with droughts lasting longer than two years projected with 3°C warming and above.    

Business-as-usual conservation by itself will not be adequate even with 1.5°C warming and additional adaptation actions will be needed. With warming above 1.5°C the habitats within the park will begin to transform.  While some taxa (e.g., birds) show resilience, the loss of habitat and insects will have indirect impacts.  Mammals show even less overall resilience than plants with increasing warming and adaptation options to maintain existing species may be limited by 4°C warming.