Half-Marathon, Climate Politics, and the Demise of RCP 8.5 Scenario

How does a half-marathon in Ottawa connect to urgent climate projections? A story weaving politics, science, and action.

Photos: Mitchell Beer/The Energy Mix

On a rainy Sunday in Ottawa, a half-marathon took place, but the real story was the backdrop of climate change discussions and the recent retirement of a significant climate projection. The event was intertwined with political activity, as Éric St-Pierre, a Liberal MP and seasoned ultramarathon runner, ran dressed as Parliament’s Peace Tower. This symbolic act coincided with the retirement of RCP 8.5, a climate projection from the Intergovernmental Panel on Climate Change (IPCC) known for its bleak high-emissions scenarios.

St-Pierre’s participation was described as a lighthearted gesture to promote public service and health. However, the political climate around climate change discussions has been far from lighthearted. Earlier this year, climate experts Simon Donner and Catherine Abreu were barred from testifying in a committee focused on Canada’s climate action plan, highlighting tensions among federal parties.

Further complicating the political landscape, 14 Liberal MPs expressed concern to Prime Minister Mark Carney about environmental assessment rollbacks. They emphasized that “climate change remains the greatest threat of our time” in a letter that was not meant for public disclosure, fearing political fallout. St-Pierre’s involvement in this letter is speculative, but his climate advocacy background suggests a possible connection.

The now-retired RCP 8.5 was originally developed to account for uncertainties in climate projections, but it often served as a worst-case scenario in scientific discourse. Although criticized for its improbability, it has been cited extensively in academic papers, leading to some alarmist projections. The recent formal withdrawal of RCP 8.5 reflects advancements in clean technologies and climate policies that have altered emission trajectories.

Despite the retirement of RCP 8.5, scientists stress that more optimistic climate scenarios are also unlikely, with current projections averaging at a global warming of 2.8°C. The path forward requires accelerated carbon reductions and constructive political dialogue, free from partisan gridlock. As Simon Donner pointed out, the political behavior observed in the committee was akin to “junior-high behaviour.”

In this climate of urgency and political maneuvering, the half-marathon in Ottawa served as a metaphor for the need for a cohesive and urgent climate response. The focus must remain on fostering collaboration and effective solutions to address the pressing climate challenges.