Black Carbon and Other Short-Lived Climate Pollutants (SLCPs): How SLCPs are Altering Our Understanding of the Global Climate System - And How This Will Require the Abandonment of the Standard Climate Metric CO2e

Abstract

Since the Kyoto Protocol, black carbon and other non-gaseous short lived climate pollutants (SLCPs) have played little role in global climate policy making. Over the past ten years, however, there has been an increasing recognition in the climate science literature of their importance for the global climate. Nevertheless, international climate policy making in practice continues to ignore the critical scientific and policy importance of the short lifetimes of these climate pollutants. This includes not only the physical particles but also the gas methane which - with its atmospheric lifetime of 12 years - is also a SLCP. The eventual necessary inclusion of SLCPs will require some major changes in the architecture of global climate policy making. The recent scientific literature, for example, concludes that the standard climate metric of carbon dioxide equivalent (CO2e) cannot validly be calculated for SLCPs (including methane). If the incorporation of SLCPs therefore means that there can be no valid CO2e for key climate pollutants, this will require some basic changes in the methods of formulating and implementing global climate policy.

Keywords: climate change, short-lived climate pollutants, black carbon, methane, carbon dioxide equivalency

JEL Classification: K20, K32, Q00, Q01, Q50, Q54, Q58