Going beyond carbon: An "Earth System Impact" score to better capture corporate and investment impacts on the Earth system

Abstract

Corporations are responsible for a significant portion of observed impacts on the Earth system, including green-house gas (GHG) emissions, but also water extraction, landuse change and other pressures on nature. These nature-related impacts are essential to consider and capture because they have local impacts on a range of ecosystem functions on which companies and economies depend, but they also fundamental affect our ability to mitigate and adapt to a changing climate. Furthermore, climate, land and water interact and affect each other in various ways, such that climate change can be exacerbated by degraded ecosystems, which in turn are dependent on water.

This paper tests a novel metric developed to capture corporate Earth system impact (ESI) beyond merely direct GHG emissions, and explores how such a tool could be used to improve assessments of corporate environmental impacts and support decisions on where to direct public and private investments. We use the mining sector as a test case to illustrate the applicability of the ESI score and examine the impact of the ten largest (by market cap) mining companies in the non-precious and non-precious metal mining sector. We find that many of the mining assets have non-negligible impacts on land and water, and can show that the ESI metric identifies a different set of asset for targeted action than conventional carbon intensity scores would do.

Keywords: Earth system, planetary boundaries, corporate impact, sustainable investments, carbon intensity