Evaluating Societal Impacts Related to Air Quality and Climate

Thanks to many colleagues, especially Greg Faluvegi & Yunha Lee

Drew Shindell

Nicholas School of the EnvironmentDuke University

Comparing impacts & robustness

Pollutant Climate Damages Health Damages Ag Damages

CO2 Very large (certain) None Medium

SO2 Opposite (global) Very large Opposite*

HFCs Large (very likely) None Very Large

Methane Large (certain) Medium Large

BC+ Moderate and/or Very large Very Largelarge uncertainty

How to decide what is best to do where?

Lock in new CO2-intenstive capital

stockReduce SO2 and NOx

(both with net cooling effects)

Avoiding Pitfalls

Currently...

To get the most out of labour, capital, and other resources, countires need to allocate them efficiently across different sectors of the economy, and to achieve this, product prices need to reflect not only the cost of supplying those products, but also any environmental costs of using them. We think prices paid by users of energy, or energy-related products, need to reflect the full range of environmental costs (air pollution, road traffic congestion…), not just global warming.

International Monetary Fund Director Christine Lagarde, 2015

Currently...Obama Administration executive order for all federal agencies to include Social Cost of Carbon (SCC) analysis: “intended to include (but not limited to) changes in net agricultural productivity, human health, property damages from increased flood risk, and the value of ecosystem services due to climate change.”

EU has the Emissions Trading System

All impacts assumed proportional to global mean annual average radiative forcing or temperature change

Air Quality falls under a variety of rules, costs typically analyzed for major legislation

Develop a broader Social Cost that includes impacts on human health, agriculture, etc. via climate & air quality; includes all the key pollutants causing both problems

Model response to emissions of one pollutant at a time

Climate impacts of pollutants other than carbon dioxide

Same valuation methodology for air quality and climate(similar work for methane/ozone/health in Sarofim, Waldhoff & Anenberg, Environ. Res. Econ., 2015)

Valuing Emissions:

Social Cost of Atmospheric Release (SCAR)

Valuing Clean Air

Generation costs from US Energy Information Administration, 2012

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Policy Benefits: US

Clean Energy & Transportation Consistent with 2°C

Shindell et al., Nature Climate Change, 2016

Policy Benefits: US

Clean Energy: Avoids ~175,000 premature deaths by 2030 (-50%/+450%; ~80% PM2.5, 20% O3)

Clean Transportation: ~120,000 lives by 2030 (-36%/+360%; ~66% PM2.5, 33% O3)

Policy Benefits: US

Implementation costs ~$100-210B (2030 economy-wide)

Shindell et al., Nature Climate Change, 2016

How Well do we Know the Values

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How Well do we Know the Values

GISS-E2 CESM1 HadGEM3

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GISS-E2 CESM1 HadGEM30

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DKasoar et al., ACPD, 2016

Need to define broad targets (e.g. UN Sustainable Development Goals)

Need to relate specific actions to broad targets (wider metrics)

Need to target efforts to improve quantification of key sources of uncertainty influencing valuation

How can policy & research maximize societal benefits?