Atmosphere Ocean Science Colloquium

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A Tale of Two Assassins: Who is responsible for the rising atmospheric burden of methane?

Speaker: Prof. Matthew Hayek, Environmental Studies, NYU

Location: Warren Weaver Hall 1302

Date: Wednesday, May 1, 2024, 3:30 p.m.

Synopsis:

Emissions of both CO2 and methane are contributing to their rising atmospheric concentrations and global warming. Methane has a very short atmospheric lifetime compared to CO2, which has consequences for mitigating climate change. I will present a global overview of methane's emission sources, and plausible scenarios of their future trajectory. I will then discuss how methane "metrics" aim to succinctly capture and compare methane's warming effects relative to CO2. One recent metric aims to more accurately reflect methane's ephemeral nature, but has also been criticized for downplaying the contributions of large emitters. I aim to show how these debates reflect widespread confusion regarding how individual actors contribute to the global atmospheric burden. This has created paralysis in deciding how to attribute responsibility or blame for methane emissions among multiple actors. I aim to resolve this confusion using a simple model of atmospheric methane, historical measurements, and a novel thought experiment--A Tale of Two Assassins. After painting a clearer picture of how to more accurately and responsibly allocate methane emissions among actors, I will conclude with a forward-looking assessment of how we can effectively mitigate warming from methane across time and space.