Unexpected slowdown of US pollutant emission reduction in the past decade.
Proc Natl Acad Sci U S A
; 115(20): 5099-5104, 2018 05 15.
Article
em En
| MEDLINE
| ID: mdl-29712822
ABSTRACT
Ground and satellite observations show that air pollution regulations in the United States (US) have resulted in substantial reductions in emissions and corresponding improvements in air quality over the last several decades. However, large uncertainties remain in evaluating how recent regulations affect different emission sectors and pollutant trends. Here we show a significant slowdown in decreasing US emissions of nitrogen oxides (NO x ) and carbon monoxide (CO) for 2011-2015 using satellite and surface measurements. This observed slowdown in emission reductions is significantly different from the trend expected using US Environmental Protection Agency (EPA) bottom-up inventories and impedes compliance with local and federal agency air-quality goals. We find that the difference between observations and EPA's NO x emission estimates could be explained by (i) growing relative contributions of industrial, area, and off-road sources, (ii) decreasing relative contributions of on-road gasoline, and (iii) slower than expected decreases in on-road diesel emissions.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Emissões de Veículos
/
Monóxido de Carbono
/
Monitoramento Ambiental
/
Poluentes Atmosféricos
/
Poluição do Ar
/
Material Particulado
/
Óxidos de Nitrogênio
Limite:
Humans
País/Região como assunto:
America do norte
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2018
Tipo de documento:
Article