The Experts below are selected from a list of 374523 Experts worldwide ranked by ideXlab platform
Joseph S Shapiro - One of the best experts on this subject based on the ideXlab platform.
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the low but uncertain measured benefits of us water Quality Policy
Proceedings of the National Academy of Sciences of the United States of America, 2019Co-Authors: Joseph S ShapiroAbstract:U.S. investment to decrease pollution in rivers, lakes, and other surface waters has exceeded $1.9 trillion since 1960, and has also exceeded the cost of most other U.S. environmental initiatives. These investments come both from the 1972 Clean Water Act and the largely voluntary efforts to control pollution from agriculture and urban runoff. This paper reviews the methods and conclusions of about 20 recent evaluations of these policies. Surprisingly, most analyses estimate that these policies’ benefits are much smaller than their costs; the benefit/cost ratio from the median study is 0.37. Yet existing evidence is limited and undercounts many types of benefits. We conclude that it is unclear whether many of these regulations truly fail a benefit/cost test or whether existing evidence understates their net benefits; we also describe specific questions that when answered would help eliminate this uncertainty.
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the low but uncertain measured benefits of us water Quality Policy
Proceedings of the National Academy of Sciences of the United States of America, 2019Co-Authors: David A Keiser, Joseph S Shapiro, Catherine L KlingAbstract:US investment to decrease pollution in rivers, lakes, and other surface waters has exceeded $1.9 trillion since 1960, and has also exceeded the cost of most other US environmental initiatives. These investments come both from the 1972 Clean Water Act and the largely voluntary efforts to control pollution from agriculture and urban runoff. This paper reviews the methods and conclusions of about 20 recent evaluations of these policies. Surprisingly, most analyses estimate that these policies’ benefits are much smaller than their costs; the benefit–cost ratio from the median study is 0.37. However, existing evidence is limited and undercounts many types of benefits. We conclude that it is unclear whether many of these regulations truly fail a benefit–cost test or whether existing evidence understates their net benefits; we also describe specific questions that when answered would help eliminate this uncertainty.
T D Fairlie - One of the best experts on this subject based on the ideXlab platform.
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variability in surface ozone background over the united states implications for air Quality Policy
Journal of Geophysical Research, 2003Co-Authors: Arlene M Fiore, Daniel J Jacob, Hongyu Liu, Robert M Yantosca, T D FairlieAbstract:average) may be unattainable. We show that a 3-D global model of tropospheric chemistry reproduces much of the observed variability in U.S. surface O3 concentrations, including the springtime high-O3 events, with only a minor stratospheric contribution (always 2 km). It declines from spring to summer and further decreases during O3 pollution episodes. The 40 ppbv background assumed by EPA thus actually underestimates the risk associated with O3 during polluted conditions. A better definition would represent background as a function of season, altitude, and total surface O3 concentration. Natural O3 levels are typically 10– 25 ppbv and never exceed 40 ppbv. International controls to reduce the hemispheric pollution background would facilitate compliance with an AOT40-type standard (cumulative exposure to O3 above 40 ppbv) in the United States. INDEX TERMS: 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305); 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry; 0368 Atmospheric Composition and Structure: Troposphere—constituent transport and chemistry; 9350 Information Related to Geographic Region: North America; KEYWORDS: background ozone, air Quality, hemispheric pollution
Arlene M Fiore - One of the best experts on this subject based on the ideXlab platform.
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variability in surface ozone background over the united states implications for air Quality Policy
Journal of Geophysical Research, 2003Co-Authors: Arlene M Fiore, Daniel J Jacob, Hongyu Liu, Robert M Yantosca, T D FairlieAbstract:average) may be unattainable. We show that a 3-D global model of tropospheric chemistry reproduces much of the observed variability in U.S. surface O3 concentrations, including the springtime high-O3 events, with only a minor stratospheric contribution (always 2 km). It declines from spring to summer and further decreases during O3 pollution episodes. The 40 ppbv background assumed by EPA thus actually underestimates the risk associated with O3 during polluted conditions. A better definition would represent background as a function of season, altitude, and total surface O3 concentration. Natural O3 levels are typically 10– 25 ppbv and never exceed 40 ppbv. International controls to reduce the hemispheric pollution background would facilitate compliance with an AOT40-type standard (cumulative exposure to O3 above 40 ppbv) in the United States. INDEX TERMS: 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305); 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry; 0368 Atmospheric Composition and Structure: Troposphere—constituent transport and chemistry; 9350 Information Related to Geographic Region: North America; KEYWORDS: background ozone, air Quality, hemispheric pollution
Daniel J Jacob - One of the best experts on this subject based on the ideXlab platform.
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systematic bias in evaluating chemical transport models with maximum daily 8 hour average mda8 surface ozone for air Quality applications
Geoscientific Model Development Discussions, 2019Co-Authors: Katherine Travis, Daniel J JacobAbstract:Abstract. Chemical transport models typically evaluate their simulation of surface ozone with observations of the maximum daily 8-hour average (MDA8) concentration, which is the standard air Quality Policy metric. This requires successful simulation of the surface ozone diurnal cycle including nighttime depletion, but models are generally biased high at night because of difficulty in resolving the stratified conditions near the surface. We quantify the problem with the GEOS-Chem model for the Southeast US during the NASA SEAC4RS aircraft campaign in August–September 2013. The model is unbiased relative to the daytime mixed layer aircraft observations but has a +5 ppb bias relative to MDA8 surface ozone observations. The model also does not capture observed occurrences of
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variability in surface ozone background over the united states implications for air Quality Policy
Journal of Geophysical Research, 2003Co-Authors: Arlene M Fiore, Daniel J Jacob, Hongyu Liu, Robert M Yantosca, T D FairlieAbstract:average) may be unattainable. We show that a 3-D global model of tropospheric chemistry reproduces much of the observed variability in U.S. surface O3 concentrations, including the springtime high-O3 events, with only a minor stratospheric contribution (always 2 km). It declines from spring to summer and further decreases during O3 pollution episodes. The 40 ppbv background assumed by EPA thus actually underestimates the risk associated with O3 during polluted conditions. A better definition would represent background as a function of season, altitude, and total surface O3 concentration. Natural O3 levels are typically 10– 25 ppbv and never exceed 40 ppbv. International controls to reduce the hemispheric pollution background would facilitate compliance with an AOT40-type standard (cumulative exposure to O3 above 40 ppbv) in the United States. INDEX TERMS: 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305); 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry; 0368 Atmospheric Composition and Structure: Troposphere—constituent transport and chemistry; 9350 Information Related to Geographic Region: North America; KEYWORDS: background ozone, air Quality, hemispheric pollution
Hongyu Liu - One of the best experts on this subject based on the ideXlab platform.
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variability in surface ozone background over the united states implications for air Quality Policy
Journal of Geophysical Research, 2003Co-Authors: Arlene M Fiore, Daniel J Jacob, Hongyu Liu, Robert M Yantosca, T D FairlieAbstract:average) may be unattainable. We show that a 3-D global model of tropospheric chemistry reproduces much of the observed variability in U.S. surface O3 concentrations, including the springtime high-O3 events, with only a minor stratospheric contribution (always 2 km). It declines from spring to summer and further decreases during O3 pollution episodes. The 40 ppbv background assumed by EPA thus actually underestimates the risk associated with O3 during polluted conditions. A better definition would represent background as a function of season, altitude, and total surface O3 concentration. Natural O3 levels are typically 10– 25 ppbv and never exceed 40 ppbv. International controls to reduce the hemispheric pollution background would facilitate compliance with an AOT40-type standard (cumulative exposure to O3 above 40 ppbv) in the United States. INDEX TERMS: 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305); 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry; 0368 Atmospheric Composition and Structure: Troposphere—constituent transport and chemistry; 9350 Information Related to Geographic Region: North America; KEYWORDS: background ozone, air Quality, hemispheric pollution
