PM2.5 and Ozone Air Pollution Levels Have Not Dropped Consistently Across the US Following Societal Covid Response

Analysis of a large national dataset of fine particulate matter (PM2.5) and ozone air pollution from the US Environmental Protection Agency indicate opposing differences in average concentrations during the covid response period, relative to expected levels. These are the two most important pollutants in terms of public health impacts and regulatory non-attainment in the US. Post-covid response, average PM2.5 levels are slightly higher (~6%) than expected; average ozone levels are slightly lower (~5%). The size of post-response ozone anomaly has decreased with time and by week 6 after the first stay-at-home order was enacted (April 29- May 5, 2020), ozone levels were higher than expected. In addition, no individual US state had lower-than-expected PM2.5 and ozone for all weeks post- covid response. Two non-covid factors, meteorology and regional transport, do not fully explain observed trends. These findings are unexpected given the large reduction in many household’s activities associated with “stay at home” and other covid responses. We hypothesize that this result partly arises from the fact that ozone and the majority of PM2.5 are secondary pollutants formed in the atmosphere from emissions from many sources (i.e., not just traffic). Preliminary analysis of nitrogen dioxide (NO2) data in a few cities reveals substantially lower-than-expected (~30%) concentrations post-covid. NO2 is a primary pollutant and is much more strongly associated with traffic than PM2.5 or ozone.

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PM2.5 and Ozone Air Pollution Levels Have Not Dropped Consistently Across the US Following Societal Covid Response

10.26434/chemrxiv.12275603.v6 ◽

2020 ◽

Cited By ~ 1

Author(s):

Bujin Bekbulat ◽

Joshua S. Apte ◽

Dylan B Millet ◽

Allen Robinson ◽

Kelley C. Wells ◽

...

Keyword(s):

Air Pollution ◽

Environmental Protection Agency ◽

Fine Particulate Matter ◽

Pollution Levels ◽

Secondary Pollutants ◽

The Us ◽

Many Sources ◽

Primary Pollutant ◽

Ozone Levels ◽

At Home

Analysis of a large national dataset of fine particulate matter (PM2.5) and ozone air pollution from the US Environmental Protection Agency indicate opposing differences in average concentrations during the covid response period, relative to expected levels. These are the two most important pollutants in terms of public health impacts and regulatory non-attainment in the US. Post-covid response, average PM2.5 levels are slightly higher (~4%) than expected; average ozone levels are slightly lower (~5%). The size of post-response ozone anomaly has decreased with time and by week 6 after the first stay-at-home order was enacted (April 29- May 5, 2020), ozone levels were higher than expected. In addition, no individual US state had lower-than-expected PM2.5 and ozone for all weeks post- covid response. Two non-covid factors, meteorology and regional transport, do not fully explain observed trends. These findings are unexpected given the large reduction in many household’s activities associated with “stay at home” and other covid responses. We hypothesize that this result partly arises from the fact that ozone and the majority of PM2.5 are secondary pollutants formed in the atmosphere from emissions from many sources (i.e., not just traffic). Preliminary analysis of nitrogen dioxide (NO2) data in a few cities reveals substantially lower-than-expected (~30%) concentrations post-covid. NO2 is a primary pollutant and is much more strongly associated with traffic than PM2.5 or ozone.

Download Full-text

PM2.5 and Ozone Air Pollution Levels Have Not Dropped Consistently Across the US Following Societal Covid Response

10.26434/chemrxiv.12275603.v7 ◽

2020 ◽

Cited By ~ 1

Author(s):

Bujin Bekbulat ◽

Joshua S. Apte ◽

Dylan B Millet ◽

Allen Robinson ◽

Kelley C. Wells ◽

...

Keyword(s):

Air Pollution ◽

Environmental Protection Agency ◽

Fine Particulate Matter ◽

Pollution Levels ◽

Secondary Pollutants ◽

The Us ◽

Many Sources ◽

Primary Pollutant ◽

Ozone Levels ◽

At Home

Analysis of a large national dataset of fine particulate matter (PM2.5) and ozone air pollution from the US Environmental Protection Agency indicate opposing differences in average concentrations during the covid response period, relative to expected levels. These are the two most important pollutants in terms of public health impacts and regulatory non-attainment in the US. Post-covid response, average PM2.5 levels are slightly higher (~3%) than expected; average ozone levels are slightly lower (~4%). The size of post-response ozone anomaly has decreased with time and by week 6 after the first stay-at-home order was enacted (April 29- May 5, 2020), ozone levels were higher than expected. In addition, no individual US state had lower-than-expected PM2.5 and ozone for all weeks post- covid response. Two non-covid factors, meteorology and regional transport, do not fully explain observed trends. These findings are unexpected given the large reduction in many household’s activities associated with “stay at home” and other covid responses. We hypothesize that this result partly arises from the fact that ozone and the majority of PM2.5 are secondary pollutants formed in the atmosphere from emissions from many sources (i.e., not just traffic). Preliminary analysis of nitrogen dioxide (NO2) data in a few cities reveals substantially lower-than-expected (~30%) concentrations post-covid. NO2 is a primary pollutant and is much more strongly associated with traffic than PM2.5 or ozone.

Download Full-text

PM2.5 and Ozone Air Pollution Levels Have Not Dropped Consistently Across the US Following Societal Covid Response

10.26434/chemrxiv.12275603.v4 ◽

2020 ◽

Cited By ~ 1

Author(s):

Bujin Bekbulat ◽

Joshua S. Apte ◽

Dylan B Millet ◽

Allen Robinson ◽

Kelley C. Wells ◽

...

Keyword(s):

Air Pollution ◽

Environmental Protection Agency ◽

Fine Particulate Matter ◽

Pollution Levels ◽

Secondary Pollutants ◽

The Us ◽

Many Sources ◽

Primary Pollutant ◽

Ozone Levels ◽

At Home

Analysis of a large national dataset of fine particulate matter (PM2.5) and ozone air pollution from the US Environmental Protection Agency indicate opposing differences in average concentrations during the covid response period, relative to expected levels. These are the two most important pollutants in terms of public health impacts and regulatory non-attainment in the US. Post-covid response, average PM2.5 levels are slightly higher (~6%) than expected; average ozone levels are slightly lower (~5%). The size of post-response ozone anomaly has decreased with time and by week 6 after the first stay-at-home order was enacted (April 29- May 5, 2020), ozone levels were higher than expected. In addition, no individual US state had lower-than-expected PM2.5 and ozone for all weeks post- covid response. Two non-covid factors, meteorology and regional transport, do not fully explain observed trends. These findings are unexpected given the large reduction in many household’s activities associated with “stay at home” and other covid responses. We hypothesize that this result partly arises from the fact that ozone and the majority of PM2.5 are secondary pollutants formed in the atmosphere from emissions from many sources (i.e., not just traffic). Preliminary analysis of nitrogen dioxide (NO2) data in a few cities reveals substantially lower-than-expected (~30%) concentrations post-covid. NO2 is a primary pollutant and is much more strongly associated with traffic than PM2.5 or ozone.

Download Full-text

PM2.5 and Ozone Air Pollution Levels Have Not Dropped Consistently Across the US Following Societal Covid Response

10.26434/chemrxiv.12275603.v1 ◽

2020 ◽

Cited By ~ 2

Author(s):

Bujin Bekbulat ◽

Joshua S. Apte ◽

Dylan B Millet ◽

Allen Robinson ◽

Kelley C. Wells ◽

...

Keyword(s):

Air Pollution ◽

Environmental Protection Agency ◽

Fine Particulate Matter ◽

Protection Agency ◽

Pollution Levels ◽

Fine Particulate ◽

Secondary Pollutants ◽

The Us ◽

Many Sources ◽

Primary Pollutant

Analysis of a large national dataset of fine particulate matter (PM2.5) and ozone air pollution from the US Environmental Protection Agency indicate opposing differences in average concentrations during the covid response period, relative to expected levels. These are the two most important pollutants in terms of public health impacts and non-attainment in the US. Post- covid response, average PM2.5 levels are modestly higher (~10%) than expected; average ozone levels are lower (~7%). However, the size of the post-response ozone anomaly is decreasing with time. In addition, no individual US state had lower-than-expected PM2.5 for all weeks post- covid response, and only one US state (California) met that criteria for ozone. Two non-covid factors, meteorology and regional transport, do not fully explain observed trends. These findings are unexpected given the large reduction in many household’s activities associated with “stay at home” and other covid responses. We hypothesize that this result partly arises from the fact that ozone and the majority of PM2.5 are secondary pollutants formed in the atmosphere from emissions from many sources (i.e., not just traffic). Preliminary analysis of nitrogen dioxide (NO2) data in a few cities reveals substantially lower-than-expected (~31%) concentrations post-covid. NO2 is a primary pollutant and is much more strongly associated with traffic than PM2.5 or ozone.

Download Full-text

PM2.5 and Ozone Air Pollution Levels Have Not Dropped Consistently Across the US Following Societal Covid Response

10.26434/chemrxiv.12275603.v2 ◽

2020 ◽

Author(s):

Bujin Bekbulat ◽

Joshua S. Apte ◽

Dylan B Millet ◽

Allen Robinson ◽

Kelley C. Wells ◽

...

Keyword(s):

Air Pollution ◽

Environmental Protection Agency ◽

Fine Particulate Matter ◽

Protection Agency ◽

Pollution Levels ◽

Fine Particulate ◽

Secondary Pollutants ◽

The Us ◽

Many Sources ◽

Primary Pollutant

Analysis of a large national dataset of fine particulate matter (PM2.5) and ozone air pollution from the US Environmental Protection Agency indicate opposing differences in average concentrations during the covid response period, relative to expected levels. These are the two most important pollutants in terms of public health impacts and non-attainment in the US. Post- covid response, average PM2.5 levels are modestly higher (~10%) than expected; average ozone levels are lower (~7%). However, the size of the post-response ozone anomaly is decreasing with time. In addition, no individual US state had lower-than-expected PM2.5 for all weeks post- covid response, and only one US state (California) met that criteria for ozone. Two non-covid factors, meteorology and regional transport, do not fully explain observed trends. These findings are unexpected given the large reduction in many household’s activities associated with “stay at home” and other covid responses. We hypothesize that this result partly arises from the fact that ozone and the majority of PM2.5 are secondary pollutants formed in the atmosphere from emissions from many sources (i.e., not just traffic). Preliminary analysis of nitrogen dioxide (NO2) data in a few cities reveals substantially lower-than-expected (~31%) concentrations post-covid. NO2 is a primary pollutant and is much more strongly associated with traffic than PM2.5 or ozone.

Download Full-text

Changes in criteria air pollution levels in the US before, during, and after Covid-19 stay-at-home orders: evidence from regulatory monitors

10.26434/chemrxiv.12275603.v8 ◽

2020 ◽

Author(s):

Bujin Bekbulat ◽

Joshua S. Apte ◽

Dylan B Millet ◽

Allen Robinson ◽

Kelley C. Wells ◽

...

Keyword(s):

Air Pollution ◽

Environmental Protection Agency ◽

Protection Agency ◽

Normal Range ◽

Economic Changes ◽

Pollution Levels ◽

National Monitoring ◽

Criteria Pollutants ◽

The Us ◽

At Home

The widespread and rapid social and economic changes from Covid-19 response might be expected to dramatically improve air quality. However, national monitoring data from the US Environmental Protection Agency for criteria pollutants (PM2.5, ozone, NO2, CO, PM10) provide inconsistent support for that expectation. Specifically, during stay-at-home orders, average PM2.5 levels were slightly higher (~10% of its multi-year interquartile range [IQR]) than expected; average ozone, NO2, CO, and PM10 levels were slightly lower (~30%, ~20%, ~27%, and ~1% of their IQR, respectively) than expected. The timing of peak anomaly, relative to the stay-at-home orders, varied by pollutant (ozone: 2 weeks before; NO2, CO: 3 weeks after; PM10: 2 weeks after); but, by 5-6 weeks after stay-at-home orders, the concentration anomalies appear to have ended. For PM2.5, ozone, CO, and PM10, no US state had lower-than-expected pollution levels for all weeks during stay-at-home-orders; for NO2, only Arizona had lower-than-expected levels for all weeks during stay-at-home orders. Our findings show that the enormous changes from the Covid response have not lowered PM2.5 levels across the US beyond their normal range of variability; for ozone, NO2, CO, and PM10 concentrations were lowered but the reduction was modest and transient.

Download Full-text

Changes in criteria air pollution levels in the US before, during, and after Covid-19 stay-at-home orders: evidence from regulatory monitors

10.26434/chemrxiv.12275603 ◽

2020 ◽

Cited By ~ 2

Author(s):

Bujin Bekbulat ◽

Joshua S. Apte ◽

Dylan B Millet ◽

Allen Robinson ◽

Kelley C. Wells ◽

...

Keyword(s):

Air Pollution ◽

Environmental Protection Agency ◽

Protection Agency ◽

Normal Range ◽

Economic Changes ◽

Pollution Levels ◽

National Monitoring ◽

Criteria Pollutants ◽

The Us ◽

At Home

The widespread and rapid social and economic changes from Covid-19 response might be expected to dramatically improve air quality. However, national monitoring data from the US Environmental Protection Agency for criteria pollutants (PM2.5, ozone, NO2, CO, PM10) provide inconsistent support for that expectation. Specifically, during stay-at-home orders, average PM2.5 levels were slightly higher (~10% of its multi-year interquartile range [IQR]) than expected; average ozone, NO2, CO, and PM10 levels were slightly lower (~30%, ~20%, ~27%, and ~1% of their IQR, respectively) than expected. The timing of peak anomaly, relative to the stay-at-home orders, varied by pollutant (ozone: 2 weeks before; NO2, CO: 3 weeks after; PM10: 2 weeks after); but, by 5-6 weeks after stay-at-home orders, the concentration anomalies appear to have ended. For PM2.5, ozone, CO, and PM10, no US state had lower-than-expected pollution levels for all weeks during stay-at-home-orders; for NO2, only Arizona had lower-than-expected levels for all weeks during stay-at-home orders. Our findings show that the enormous changes from the Covid response have not lowered PM2.5 levels across the US beyond their normal range of variability; for ozone, NO2, CO, and PM10 concentrations were lowered but the reduction was modest and transient.

Download Full-text

Changes in criteria air pollution levels in the US before, during, and after Covid-19 stay-at-home orders: evidence from regulatory monitors

10.26434/chemrxiv.12275603.v10 ◽

2020 ◽

Author(s):

Bujin Bekbulat ◽

Joshua S. Apte ◽

Dylan B Millet ◽

Allen Robinson ◽

Kelley C. Wells ◽

...

Keyword(s):

Air Pollution ◽

Environmental Protection Agency ◽

Protection Agency ◽

Normal Range ◽

Economic Changes ◽

Pollution Levels ◽

National Monitoring ◽

Criteria Pollutants ◽

The Us ◽

At Home

The widespread and rapid social and economic changes from Covid-19 response might be expected to dramatically improve air quality. However, national monitoring data from the US Environmental Protection Agency for criteria pollutants (PM2.5, ozone, NO2, CO, PM10) provide inconsistent support for that expectation. Specifically, during stay-at-home orders, average PM2.5 levels were slightly higher (~10% of its multi-year interquartile range [IQR]) than expected; average ozone, NO2, CO, and PM10 levels were slightly lower (~30%, ~20%, ~27%, and ~1% of their IQR, respectively) than expected. The timing of peak anomaly, relative to the stay-at-home orders, varied by pollutant (ozone: 2 weeks before; NO2, CO: 3 weeks after; PM10: 2 weeks after); but, by 5-6 weeks after stay-at-home orders, the concentration anomalies appear to have ended. For PM2.5, ozone, CO, and PM10, no US state had lower-than-expected pollution levels for all weeks during stay-at-home-orders; for NO2, only Arizona had lower-than-expected levels for all weeks during stay-at-home orders. Our findings show that the enormous changes from the Covid response have not lowered PM2.5 levels across the US beyond their normal range of variability; for ozone, NO2, CO, and PM10 concentrations were lowered but the reduction was modest and transient.

Download Full-text

Changes in criteria air pollution levels in the US before, during, and after Covid-19 stay-at-home orders: evidence from regulatory monitors

10.26434/chemrxiv.12275603.v9 ◽

2020 ◽

Author(s):

Bujin Bekbulat ◽

Joshua S. Apte ◽

Dylan B Millet ◽

Allen Robinson ◽

Kelley C. Wells ◽

...

Keyword(s):

Air Pollution ◽

Environmental Protection Agency ◽

Protection Agency ◽

Normal Range ◽

Economic Changes ◽

Pollution Levels ◽

National Monitoring ◽

Criteria Pollutants ◽

The Us ◽

At Home

The widespread and rapid social and economic changes from Covid-19 response might be expected to dramatically improve air quality. However, national monitoring data from the US Environmental Protection Agency for criteria pollutants (PM2.5, ozone, NO2, CO, PM10) provide inconsistent support for that expectation. Specifically, during stay-at-home orders, average PM2.5 levels were slightly higher (~10% of its multi-year interquartile range [IQR]) than expected; average ozone, NO2, CO, and PM10 levels were slightly lower (~30%, ~20%, ~27%, and ~1% of their IQR, respectively) than expected. The timing of peak anomaly, relative to the stay-at-home orders, varied by pollutant (ozone: 2 weeks before; NO2, CO: 3 weeks after; PM10: 2 weeks after); but, by 5-6 weeks after stay-at-home orders, the concentration anomalies appear to have ended. For PM2.5, ozone, CO, and PM10, no US state had lower-than-expected pollution levels for all weeks during stay-at-home-orders; for NO2, only Arizona had lower-than-expected levels for all weeks during stay-at-home orders. Our findings show that the enormous changes from the Covid response have not lowered PM2.5 levels across the US beyond their normal range of variability; for ozone, NO2, CO, and PM10 concentrations were lowered but the reduction was modest and transient.

Download Full-text