Harvard Climate Seminar

Sonia I. Seneviratne Professor, Department of Environmental Systems Science ETH Zurich, Land-Climate Dynamics Institute for Atmospheric and Climate Science  

Climate extremes at 1.5°C vs 2°C global warming: The IPCC SR15 report and underlying evidence

In this presentation I will provide an overview on changes in climate extremes at 1.5°C vs 2°C global warming, as assessed in the recent IPCC special report on 1.5°C global warming (http://ipcc.ch/report/sr15/). In particular, I will address the differences in climate extremes that can be distinguished at these two warming levels, as well as associated impacts. Some impacts are irreversible when reaching a 2°C global warming, highlighting the importance of avoiding a possible overshoot in emissions trajectories towards this limit. I will also highlight how changes in extremes can be related to mean global warming, why regional hot extremes warm more than the global mean temperature, and the role of land processes and land use changes in these projections.

References: IPCC, 2018: Global warming of 1.5°C - Summary for Policymakers (available from: http://report.ipcc.ch/sr15/pdf/sr15_spm_final.pdf) Seneviratne, S.I., et al. 2018: The many possible climates from the Paris Agreement's aim of 1.5°C warming. Nature, 558, 41-49. Seneviratne, S.I., et al. 2016: Allowable CO2 emissions based on regional and impact-related climate targets. Nature, 529, 477-483.

 

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