Domestic Mitigation of Black Carbon From Diesel Emissions

• Date: 01 February 2011
• Author: Hannah Chang

41 ELR 10126 ENVIRONMENTAL LAW REPORTER 2-2011

Domestic

Mitigation of

Black Carbon

From Diesel

Emissions

by Hannah Chang

Hannah Chang wrote this Article while a Fellow at

Columbia Law School’s Center for Climate Change Law.



Black carbon, a component of soot and particulate

matter, competes closely with methane as the larg-

est anthropogenic contributor to global warming

after carbon dioxide. Regulation of black carbon ha s

been identied as an aordable, politically feasible,

fast-action means to mitigate the warming tempera-

tures caused by climate change. With an emphasis on

domestic mitigation, this Article examines how emis-

sions are controlled under the CAA and what EPA,

states, and municipalities can do to mitigate black car-

bon emissions further.

Black carbon (BC), a component of soot and particu-

late matter (PM), competes closely with methane

as the largest anthropogenic contributor to global

warming after carbon dioxide (CO2).1 Both domestically

and internationally, BC can be mitigated by aordable tech-

nologies that already exist. Moreover, such mitigation has

nearly immediate eects, as BC remains in the atmosphere

for mere days or weeks, in contrast to CO2, which remains

in the atmosphere for a century or more.2 BC is linked to

cardiovascular symptoms and decrea sed lung fu nction, so

mitigation also produces tremendous public health ben-

ets. As a result, BC’s prole as the “lowest hanging of the

low-hanging fruit”—an aordable, politically feasible, fast-

action means to mitigate the warming temperatures caused

by climate change3—has risen in recent years, especially in

the arena of international mitigation.4

BC emissions from dierent sources have dierent

warming eects, however. Whereas fossil fuel soot is clearly

warming, biomass soot has a lesser warming eect on the

climate and may even have a net cooling eect. Conse-

quently, one of the key conclusions drawn at an April 2010

Yale Climate and Energy Institute workshop on BC was

that diesel emissions, a prime source of fossil fuel soot,

should be the target of mitigation eorts, rather than emis-

sions f rom biofuel-burning cookstoves, which have been

the center of attention to date.5

Although the United States is a relatively small contrib-

utor to worldwide BC emissions, it has per capita emissions

comparable to t hose in developing regions where the vast

majority of BC is emitted.6 Moreover, diesel emissions—

the sort of emissions that have an undeniable warming

1. Jessica Seddon Wallack & Veerabhadran Ramanathan,  

, 88 F A. 105,

106 (2009).

2. Id. at 107.

3. Andrew Childers, Environmental Groups Discuss Ways to Reduce Impact of

Black Carbon, BNA Daily Env’t Rep. A-1 (Mar. 6, 2009).

4. e United Nation Environment Programme’s Integrated Assessment on

Black Carbon and Ozone, a report that aims to dene the climate, air pol-

lution, health, and agriculture impacts of BC and ozone and examines the

temperature impacts of feasible mitigation measures, is expected to be re-

leased in February 2011.

5. Bidisha Banerjee, -

(July 2010), available at http://www.yaleclimatemediafo-

rum.org/2010/07/black-carbons-grey-areas/, and http://www.yaleclimate-

mediaforum.org/2010/07/black-carbons-grey-areas-pt2/.  , Flavia

Krause-Jackson & Peter S. Green,  

Clean Energy Cookstoves, Bloomberg, Sept. 20, 2010, http://www.bloom-

berg.com/news/2010-09-20/shell-u n-to-back-100-million-plan-for-clea n-

energy-cookstoves.html.

6.     

and Global Warming, 111th Cong. 5 (2010) (statement of V. Ramanathan,

Scripps Institution of Oceanography); John-Michael Cross, 

to Reduce Black Carbon Emissions (Climate Inst. 2009), available at http://

www.climate.org/publications/Climate%20Alerts/Autumn2009/BCreduc-

tions.html.

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