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Sample records for 8-hour ozone national

  1. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  2. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  3. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ozone NAAQS are codified in 40 CFR part 81. ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  4. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... with respect to the 1997 ozone NAAQS are codified in 40 CFR part 81. ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  5. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... with respect to the 1997 ozone NAAQS are codified in 40 CFR part 81. ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  6. 75 FR 57220 - Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: New Source Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-20

    ..., e-mail address, and telephone and fax numbers. Questions concerning the August 24, 2010 (75 FR 51960... holding the public hearing was published in the Federal Register on August 24, 2010 (75 FR 51960), and is... AGENCY 40 CFR Part 51 RIN 2060-AP30 Rule To Implement the 1997 8-Hour Ozone National Ambient Air...

  7. 77 FR 28423 - Final Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-14

    ... based.'' The process for making these adjustments is described at 69 FR 23863 et seq. (April 30, 2004... rulemaking (74 FR 2936). \\1\\ 74 FR 2936, January 16, 2009. III. This Action A. Classification of 8-Hour Ozone... Determination, pursuant to 40 CFR 51.918, 70 FR 71702). The obligation to complete and submit those...

  8. 75 FR 51960 - Proposed Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: New...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-24

    ... designation (for most areas the effective date of the 1997 8-hour designation was June 15, 2004). 40 CFR 51... (69 FR 23951, April 30, 2004). The rule further provides that an area remains subject to these applicable requirements until the area attains the 1997 8-hour NAAQS. 40 CFR 51.905(b). Additionally,...

  9. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... purposes of the 8-hour ozone NAAQS? (a) What is the attainment demonstration requirement for an...

  10. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... purposes of the 8-hour ozone NAAQS? (a) What is the attainment demonstration requirement for an...

  11. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... purposes of the 8-hour ozone NAAQS? (a) What is the attainment demonstration requirement for an...

  12. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... purposes of the 8-hour ozone NAAQS? (a) What is the attainment demonstration requirement for an...

  13. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  14. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  15. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  16. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  17. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  18. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 2 2014-07-01 2014-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  19. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 2 2012-07-01 2012-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  20. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  1. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 2 2013-07-01 2013-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  2. 76 FR 54412 - Determination of Nonattainment and Reclassification of the Baltimore 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... Part 81 Air pollution control, National parks, Wilderness areas. Authority: 42 U.S.C. 7401 et seq... Baltimore Area) did not attain the 1997 8-hour ozone national ambient air quality standard (NAAQS) by its... Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103. D. Hand Delivery: At...

  3. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? Upon...

  4. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? Upon...

  5. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? Upon...

  6. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? Upon...

  7. 75 FR 79302 - Determination of Nonattainment and Reclassification of the Dallas/Fort Worth 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-20

    ...-Hour Ozone Nonattainment Area; Texas AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule... nonattainment area failed to attain the 1997 8-hour ozone national ambient air quality standard (NAAQS or... Federal Regulations (CFR) for moderate nonattainment areas. This final determination is based on...

  8. 76 FR 13289 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard in the Baltimore...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-11

    ...).) List of Subjects in 40 CFR Part 81 Environmental protection, Air pollution control, National parks... Baltimore nonattainment area, which is classified as moderate for the 1997 8-hour ozone National Ambient Air....S. Environmental Protection Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania...

  9. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas? The requirements for new source review for the 8-hour ozone standard are located in § 51.165 of this part....

  10. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas? The requirements for new source review for the 8-hour ozone standard are located in § 51.165 of this part....

  11. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas? The requirements for new source review for the 8-hour ozone standard are located in § 51.165 of this part....

  12. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas? The requirements for new source review for the 8-hour ozone standard are located in § 51.165 of this part....

  13. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas? The requirements for new source review for the 8-hour ozone standard are located in § 51.165 of this part....

  14. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918 Section 51.918 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements...

  15. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  16. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  17. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  18. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  19. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  20. 40 CFR 52.1393 - Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the 1997 8-hour ozone and PM2.5 NAAQS. 52.1393 Section 52.1393 Protection of Environment ENVIRONMENTAL... (CONTINUED) Montana § 52.1393 Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS. The... Section 110(a)(2)(D)(i) for the 8-hour ozone and PM2.5 NAAQS promulgated in July 1997. The...

  1. 40 CFR 52.1393 - Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the 1997 8-hour ozone and PM2.5 NAAQS. 52.1393 Section 52.1393 Protection of Environment ENVIRONMENTAL... (CONTINUED) Montana § 52.1393 Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS. The... Section 110(a)(2)(D)(i) for the 8-hour ozone and PM2.5 NAAQS promulgated in July 1997. The...

  2. 40 CFR 52.1393 - Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the 1997 8-hour ozone and PM2.5 NAAQS. 52.1393 Section 52.1393 Protection of Environment ENVIRONMENTAL... (CONTINUED) Montana § 52.1393 Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS. The... Section 110(a)(2)(D)(i) for the 8-hour ozone and PM2.5 NAAQS promulgated in July 1997. The...

  3. 40 CFR 52.1393 - Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the 1997 8-hour ozone and PM2.5 NAAQS. 52.1393 Section 52.1393 Protection of Environment ENVIRONMENTAL... (CONTINUED) Montana § 52.1393 Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS. The... Section 110(a)(2)(D)(i) for the 8-hour ozone and PM2.5 NAAQS promulgated in July 1997. The...

  4. 40 CFR 52.2499 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.2499 Section 52.2499 Protection of Environment ENVIRONMENTAL PROTECTION...) Washington § 52.2499 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On January 17, 2007,...

  5. 40 CFR 52.97 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.97 Section 52.97 Protection of Environment ENVIRONMENTAL PROTECTION....97 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On February 7, 2008, the...

  6. 40 CFR 52.97 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.97 Section 52.97 Protection of Environment ENVIRONMENTAL PROTECTION....97 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On February 7, 2008, the...

  7. 40 CFR 52.97 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.97 Section 52.97 Protection of Environment ENVIRONMENTAL PROTECTION....97 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On February 7, 2008, the...

  8. 40 CFR 52.2499 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.2499 Section 52.2499 Protection of Environment ENVIRONMENTAL PROTECTION...) Washington § 52.2499 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On January 17, 2007,...

  9. 40 CFR 52.97 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.97 Section 52.97 Protection of Environment ENVIRONMENTAL PROTECTION....97 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On February 7, 2008, the...

  10. 40 CFR 52.2499 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.2499 Section 52.2499 Protection of Environment ENVIRONMENTAL PROTECTION...) Washington § 52.2499 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On January 17, 2007,...

  11. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of... Air Quality Standard § 51.917 What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  12. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of... Air Quality Standard § 51.917 What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  13. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of... Air Quality Standard § 51.917 What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  14. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of... Air Quality Standard § 51.917 What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  15. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of... Air Quality Standard § 51.917 What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  16. Trends analyses of 30 years of ambient 8 hour ozone and precursor monitoring data in the South Central U.S.: progress and challenges.

    PubMed

    Sather, Mark E; Cavender, Kevin

    2016-07-13

    In the last 30 years ambient ozone concentrations have notably decreased in the South Central U.S. Yet, current ambient ozone concentrations measured over the past three years 2013-2015 in this area of the U.S. are not meeting the U.S. 2015 8 hour ozone standard of 70 parts per billion (ppb). This paper provides an update on long-term trends analyses of ambient 8 hour ozone and ozone precursor monitoring data collected over the past 30 years (1986-2015) in four South Central U.S. cities, following up on two previously published reviews of 20 and 25 year trends for these cities. All four cities have benefitted from national ozone precursor controls put in place during the 1990s and 2000s involving cleaner vehicles (vehicle fleet turnover/replacement over time), cleaner fuels, cleaner gasoline and diesel engines, and improved inspection/maintenance programs for existing vehicles. Additional ozone precursor emission controls specific to each city are detailed in this paper. The controls have resulted in impressive ambient ozone and ambient ozone precursor concentration reductions in the four South Central U.S. cities over the past 30 years, including 31-70% ambient nitrogen oxides (NOx) concentration declines from historical peaks to the present, 43-72% volatile organic compound (VOC) concentration declines from historical peaks to the present, a related 45-76% VOC reactivity decline for a subset of VOC species from historical peaks to the present, and an 18-38 ppb reduction in city 8 hour ozone design value concentrations. A new challenge for each of the four South Central U.S. cities will be meeting the U.S. 2015 8 hour ozone standard of 70 ppb. PMID:27282109

  17. 75 FR 68733 - Approval and Promulgation of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    ... for a 1-year extension, the Philadelphia Area's 4th highest daily 8-hour monitored ozone value during...), as required by 40 CFR 51.907(a). The highest-reading monitoring site had a 4th high value for 2009 of... Control Measure'' proposed July 22, 2010 (75 FR 42672); and (2) The maximum 4th highest daily...

  18. 76 FR 33647 - Approval and Promulgation of Determination of Attainment for the 1997 8-Hour Ozone Standard...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-09

    .... Louis (MO-IL) metropolitan nonattainment area on February 28, 2011 (76 FR 10815). A detailed discussion... that the area has attained the NAAQS during the 2008- 2010 monitoring period. On March 27, 2008 (73 FR... addressed this 2008 revised standard and proposed to set the primary 8-hour ozone standard within the...

  19. 76 FR 2859 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Adoption of 8-hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-18

    ... of 8-hour Ozone Standard and Related Reference Conditions, and Update of Appendices AGENCY... reference conditions, and updating the list of appendices under ``Documents Incorporated by Reference.'' In... Reference Conditions, and Update of Appendices,'' that is located in the ``Rules and Regulations''...

  20. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... classified as moderate or higher under subpart 2 pursuant to § 51.903? An area classified as moderate or... area subject only to subpart 1 in accordance with § 51.902(b)? An area subject to § 51.902(b) shall be... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection...

  1. 76 FR 10815 - Approval and Promulgation of Determination of Attainment for the 1997 8-Hour Ozone Standard...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-28

    ... 12898 (59 FR 7629, February 16, 1994). In addition, this proposed 8-hour ozone clean NAAQS data... that the area has attained the NAAQS during the 2008-2010 monitoring period. On March 27, 2008 (73 FR... by the Office of Management and Budget under Executive Order 12866 (58 FR 51735, October 4,...

  2. 40 CFR 52.1989 - Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS. 52.1989 Section 52.1989 Protection of Environment ENVIRONMENTAL... (CONTINUED) Oregon § 52.1989 Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS....

  3. 78 FR 65877 - Approval and Promulgation of Implementation Plans; Atlanta, Georgia 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... noted, EPA has already approved Rule (jjj). See 64 FR 67491 and 74 FR 62249. This rulemaking does not... Georgia's ROP plan for the 1-hour ozone NAAQS for the Atlanta Area on April 26, 1999. See 64 FR 20196. \\3..., Paulding, and Rockdale. See 56 FR 56694, November 6, 1991. \\4\\ Seven additional ``ring'' counties...

  4. 78 FR 32135 - Approval and Promulgation of Implementation Plans; Atlanta, Georgia 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-29

    ... the 1-hour ozone NAAQS for the Atlanta Area on April 26, 1999. See 64 FR 20196. \\3\\ The 13-County... Area's original attainment date was June 15, 2007. See 69 FR 23951, April 30, 2004. The Atlanta Area.... See 73 FR 12013, March 6, 2008. When an area is reclassified, a new attainment date for...

  5. 40 CFR 51.906 - Redesignation to nonattainment following initial designations for the 8-hour NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality... subsequently redesignated to nonattainment for the 8-hour ozone NAAQS, any absolute, fixed date applicable...

  6. 40 CFR 51.906 - Redesignation to nonattainment following initial designations for the 8-hour NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality... subsequently redesignated to nonattainment for the 8-hour ozone NAAQS, any absolute, fixed date applicable...

  7. 40 CFR 51.906 - Redesignation to nonattainment following initial designations for the 8-hour NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality... subsequently redesignated to nonattainment for the 8-hour ozone NAAQS, any absolute, fixed date applicable...

  8. 40 CFR 51.906 - Redesignation to nonattainment following initial designations for the 8-hour NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality... subsequently redesignated to nonattainment for the 8-hour ozone NAAQS, any absolute, fixed date applicable...

  9. 75 FR 8331 - Adequacy Status of the Cincinnati, Ohio/Indiana Submitted 8-Hour Ozone Redesignation and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-24

    ... submitted SIP budgets in our July 1, 2004, preamble starting at 69 FR 40038, and we used the information in... (NOx) as precursors to ozone in the Ohio and Indiana portions of the Cincinnati-Hamilton,...

  10. 76 FR 2829 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Adoption of 8-hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-18

    ... NAAQS for ozone on March 27, 2008 (73 FR 16436). II. Summary of SIP Revision On September 27, 2010, the... Budget under Executive Order 12866 (58 FR 51735, October 4, 1993); Does not impose an information...); Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August...

  11. 75 FR 47746 - Determination of Nonattainment and Reclassification of the Dallas/Fort Worth 1997 8-hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-09

    .... It is not usually emitted directly into the air, but at ground level is created by a chemical reaction between volatile organic compounds (VOCs) and oxides of nitrogen (NO X ) in the presence of... is more protective than the previous 1-hour ozone standard (62 FR 38855) that was established by...

  12. 40 CFR 51.913 - How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.913... designated nonattainment for the 8-hour ozone NAAQS and for any area in a section 184 ozone transport region...) A section 182(f) NOX exemption granted for the 1-hour ozone standard does not relieve the area...

  13. 40 CFR 51.915 - What emissions inventory requirements apply under the 8-hour NAAQS?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.915 What... emissions inventories for these areas, the ozone-relevant data element requirements under 40 CFR part...

  14. 40 CFR 51.915 - What emissions inventory requirements apply under the 8-hour NAAQS?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.915 What... emissions inventories for these areas, the ozone-relevant data element requirements under 40 CFR part...

  15. 40 CFR 51.915 - What emissions inventory requirements apply under the 8-hour NAAQS?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.915 What... emissions inventories for these areas, the ozone-relevant data element requirements under 40 CFR part...

  16. Eastern Texas Air Quality Forecasting System to Support TexAQS-II and 8-hour Ozone Modeling

    NASA Astrophysics Data System (ADS)

    Byun, D. W.

    2005-12-01

    The main objective of the Second Texas Air Quality Study (TexAQS-II) for 2005 and 2006 is to understand emissions and processes associated with the formation and transport of ozone and regional haze in Texas. The target research area is the more populated eastern half of the state, roughly from Interstate 35 eastward. Accurate meteorological and photochemical modeling efforts are essential to support this study and further enhance modeling efforts for establishing the State Implementation Plan (SIP) by Texas Commission on Environmental Quality (TCEQ). An air quality forecasting (AQF) system for Eastern Texas has been developed to provide these data and to further facilitate retrospective simulations to allow for model improvement and increased understanding of ozone episodes and emissions. We perform two-day air quality forecasting simulations with the 12-km Eastern Texas regional domain, and the 4-km Houston-Galveston area (HGA) domain utilizing a 48-CPU Beowulf Linux computer system. The dynamic boundary conditions are provided by the 36-km resolution conterminous US (CONUS) domain CMAQ simulations. Initial meteorological conditions are provided by the daily ETA forecast results. The results of individual runs are stored and made available to researchers and state and local officials via internet to study the patterns of air quality and its relationship to weather conditions and emissions. The data during the pre- and post-processing stages are in tens of gigabytes and must be managed efficiently during both the actual real-time and the subsequent computation periods. The nature of these forecasts and the time at which the initial data is available necessitates that models be executed within tight deadlines. A set of complex operational scripts is used to allow automatic operation of the data download, sequencing processors, performing graphical analysis, building database archives, and presenting on the web.

  17. 77 FR 65490 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Fredericksburg 8-Hour...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-29

    ... ambient air quality standard (NAAQS) for ozone. This action is being taken under the Clean Air Act (CAA... requirements of Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272...; Fredericksburg 8-Hour Ozone Maintenance Area Revision to Approved Motor Vehicle Emissions Budgets...

  18. 40 CFR 51.915 - What emissions inventory requirements apply under the 8-hour NAAQS?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.915 What... emissions inventory requirement in section 172(c)(3) of the Act shall apply, and an emission inventory SIP... emissions inventories for these areas, the ozone-relevant data element requirements under 40 CFR part...

  19. A Procedure for Inter-Comparing the Skill of Regional-Scale Air Quality Model Simulations of Daily Maximum 8-Hour Ozone Concentrations

    EPA Science Inventory

    An operational model evaluation procedure is described to quantitatively assess the relative skill among several regionalscale air quality models simulating various percentiles of the cumulative frequency distribution of observed daily maximum 8-h ozone concentrations. Bootstrap ...

  20. 40 CFR 51.913 - How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... provisions apply for the 8-hour NAAQS? 51.913 Section 51.913 Protection of Environment ENVIRONMENTAL... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.913... petition the Administrator for an exemption from NOX obligations under section 182(f) for any...

  1. 40 CFR 51.913 - How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... provisions apply for the 8-hour NAAQS? 51.913 Section 51.913 Protection of Environment ENVIRONMENTAL... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.913... petition the Administrator for an exemption from NOX obligations under section 182(f) for any...

  2. 75 FR 2935 - Extension of Deadline for Promulgating Designations for the 2008 Ozone National Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ..., 2008, EPA promulgated revised 8-hour primary and secondary ozone NAAQS (73 FR 16436; March 27, 2008... Protection Agency 40 CFR Parts 50, 58 and 81 Ozone National Ambient Air Quality Standards; Final Rule and... Designations for the 2008 Ozone National Ambient Air Quality Standards AGENCY: Environmental Protection...

  3. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  4. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  5. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  6. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  7. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  8. 40 CFR 52.1989 - Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Act section 169A and 40 CFR 51.308(e) regarding Best Available Retrofit Technology and the requirements of 40 CFR 51.308(d)(2) and (d)(4)(v) regarding the calculation of baseline and natural conditions... National Park, Diamond Peak Wilderness Area, Three Sisters Wilderness Area, Strawberry Mountain...

  9. 40 CFR 52.1989 - Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Act section 169A and 40 CFR 51.308(e) regarding Best Available Retrofit Technology and the requirements of 40 CFR 51.308(d)(2) and (d)(4)(v) regarding the calculation of baseline and natural conditions... National Park, Diamond Peak Wilderness Area, Three Sisters Wilderness Area, Strawberry Mountain...

  10. 75 FR 80420 - Reasonable Further Progress Requirements for the 1997 8-Hour Ozone National Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-22

    ... discussion of EPA's rationale for applying this interpretation in the Phase 2 Rule, see 70 FR at 71647- 49... FR 71612, November 29, 2005). \\2\\ The memorandum is available on the EPA Technology and Transfer... approach for crediting reductions from outside nonattainment areas (``outside'' reductions). See 72...

  11. 77 FR 75386 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Fredericksburg 8-Hour...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-20

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION...; Fredericksburg 8-Hour Ozone Maintenance Area Revision to Approved Motor Vehicle Emissions Budgets AGENCY: Environmental Protection Agency (EPA). ] ACTION: Final rule; correcting amendment. SUMMARY: This...

  12. 40 CFR 51.907 - For an area that fails to attain the 8-hour NAAQS by its attainment date, how does EPA interpret...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.907 For an area that... 40 Protection of Environment 2 2012-07-01 2012-07-01 false For an area that fails to attain the 8... the CAA? 51.907 Section 51.907 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  13. 40 CFR 51.907 - For an area that fails to attain the 8-hour NAAQS by its attainment date, how does EPA interpret...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.907 For an area that... 40 Protection of Environment 2 2014-07-01 2014-07-01 false For an area that fails to attain the 8... the CAA? 51.907 Section 51.907 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  14. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... decimal place of the computed value is rounded, with values equal to or greater than 5 rounding up. Thus....089 0.086 0.084 0.080 1995 98% 0.087 0.085 0.083 0.080 0.075 Average 98% (2) As shown in example...

  15. The National Ozone Expedition, 1986

    SciTech Connect

    Solomon, S. )

    1987-01-01

    Eighteen scientists from four separate institutions came to McMurdo Station during the period from August to November, 1986, to carry out an intensive stratospheric measurement program aimed at obtaining further data on the antarctic ozone hole. The results from the composite of experiments strongly suggest that chemistry (specifically, the chemistry of anthropogenically produced halocarbon species) probably plays an important role in the development of the antarctic ozone hole. If the antarctic ozone hole is due to mankind's use of chlorofluorocarbons, then it represents the first time that the environment has been shown to be sensitive to man's activities on a global scale.

  16. 40 CFR 51.915 - What emissions inventory requirements apply under the 8-hour NAAQS?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... emissions inventories for these areas, the ozone-relevant data element requirements under 40 CFR part 51... nonattainment area subject only to title I, part D, subpart 1 of the Act in accordance with § 51.902(b), the... apply under the 8-hour NAAQS? 51.915 Section 51.915 Protection of Environment ENVIRONMENTAL...

  17. High ozone concentrations in the Great Smoky Mountains National Park

    SciTech Connect

    Mueller, S.F.

    1994-12-31

    The Great Smoky Mountains National Park (GSMNP) is located in the southern Appalachian Mountains of eastern Tennessee and western North Carolina. Concern over the impact of ambient ozone on sensitive vegetation in the park has prompted a more detailed study of the cause and extent of this pollutant. The National Park Service (NPS) and the Tennessee Valley Authority (TVA) are cooperating on a joint study of ozone and its effects.

  18. 40 CFR 51.906 - Redesignation to nonattainment following initial designations for the 8-hour NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... following initial designations for the 8-hour NAAQS. 51.906 Section 51.906 Protection of Environment... Standard § 51.906 Redesignation to nonattainment following initial designations for the 8-hour NAAQS. For any area that is initially designated attainment or unclassifiable for the 8-hour NAAQS and that...

  19. Update of national ozone study: Where are we now?

    SciTech Connect

    Mathur, B.

    1996-12-31

    This paper is one of three keynote presentations given at the conference. It addresses the issue of national ozone research in focusing on the regional task force, Ozone Transport Assessment Group (OTAG). The overall objectives of the OTAG initiatives are reported. These include development of a comprehensive regional emissions inventory, selection of research models and protocols, identification of criteria for selecting emissions control strategies, and development of a framework for a NO{sub x} trading system. Findings from preliminary modeling runs and analyses are presented. 15 figs., 15 tabs.

  20. Ozone in Spain's national parks and protected forests.

    PubMed

    Sanz, María J; Sanz, Francisco; Calatayud, Vicent; Sanchez-Peña, Gerardo

    2007-01-01

    In general, it is difficult to measure air pollutant concentrations in remote areas, as they are mostly national parks and protected areas. Passive samplers provide an accurate and inexpensive method for measuring cumulative exposures of different air pollutants. They have been used to collect ozone data in both laboratory and field at different geographical scales. The objective of the present study is to fill the knowledge gap regarding air quality in remote areas of Spain, such as national parks and protected areas. Because there were no systematic data sets on the main air pollutants that could affect these areas, an air quality measurement network was established between 2001 and 2004 on 19 locations inside Spanish national parks and protected areas. The data collected suggest that ozone levels in mountainous areas are high enough to affect sensitive vegetation. Most of the locations registered moderate-to-high ozone levels, with important interannual variability. Altitudinal ozone gradients were observed in most of the parks with complex topography due to the establishment of local circulations that incorporate polluted air masses from polluted airsheds or even long-range transport (i.e., Canary Islands). Different latitude-dependent, yearly cycles were also observed, showing two, one, or no clear peaks depending on the region. These findings extend to the most southerly locations, except in the Canary Islands, where pollution transported from other regions in the upper transport layers probably led to the high concentrations observed.

  1. 75 FR 80340 - Approval and Promulgation of Implementation Plans; New Jersey; 8-Hour Ozone Control Measures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-22

    ... consists of two new rules, Subchapter 26, ``Prevention of Air Pollution From Adhesives, Sealants, Adhesive Primers and Sealant Primers,'' and Subchapter 34, ``TBAC Emissions Reporting,'' (TBAC means tertiary butyl acetate or t-butyl acetate) and revisions to Subchapter 23, ``Prevention of Air Pollution...

  2. 75 FR 9781 - Determination of Nonattainment and Reclassification of the Atlanta, Georgia, 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ... standard, was approved by EPA on March 6, 2008 (73 FR 12013). However, EPA inadvertently excluded Hall... this action. Statutory and Executive Order Reviews Under Executive Order 12866 (58 FR 51735, October 4... Use'' (66 FR 28355, May 22, 2001). This action merely corrects an inadvertent error of omission in...

  3. 78 FR 45188 - Agency Information Collection Activities; Proposed Collection; Comment Request; 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-26

    ... Protection Agency, T.W. Alexander Drive, Research Triangle Park, NC 27711; telephone number: (919) 541-2363...., Monday through Friday, excluding legal holidays. The telephone number for the Reading Room is 202-566... information, including the validity of the methodology and assumptions used; (iii) enhance the...

  4. 78 FR 47572 - Disapproval of State Implementation Plan; Infrastructure Requirements for the 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-06

    ... restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are..., section 110(a)(2)(E)(ii), is described in detail in our proposal of May 31, 2013 (78 FR 32613). The...

  5. 78 FR 32613 - Disapproval of State Implementation Plan; Infrastructure Requirements for the 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-31

    ... 0.12 parts per million (ppm) to 0.08 ppm (62 FR 38856). By statute, SIPs meeting the requirements of..., 2007, which was determined to be complete on March 27, 2008 (73 FR 16205), and another dated December 22, 2009. On May 19, 2011 (76 FR 28934), EPA published a notice of proposed rulemaking (NPR) for...

  6. 78 FR 32222 - Approval and Promulgation of Implementation Plans; Atlanta, Georgia 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-29

    ... 73 FR 16436. The current action, however, is being taken to address requirements under the earlier..., Gwinnett, Hall, Henry, Newton, Paulding, Rockdale, Spalding and Walton Counties in Georgia. EPA is...

  7. 78 FR 44439 - Approval and Promulgation of Implementation Plans: Atlanta, Georgia 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ... institute a second comment period on this action. DATES: The direct final rule published at 78 FR 32135 on... May 29, 2013 (78 FR 32135), EPA published a direct final rulemaking to approve Georgia's October 21... action, also published on May 29, 2013 (78 FR 32222). EPA will not institute a second comment period...

  8. 78 FR 34965 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... accepted during the Regional Office ] normal hours of operation, and special arrangements should be made... second comment period. Any parties interested in commenting on this action should do so at this...

  9. 75 FR 42672 - Approval and Promulgation of Implementation Plans; New Jersey; 8-hour Ozone Control Measures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ... conditionally approved. See 74 FR 22837 (May 15, 2009). If EPA approves this proposed SIP revision, the RACT... Subchapter 24 occurred on January 25, 2006 (71 FR 4045). EPA had previously approved Subchapter 24 provisions... FR 2938 (January 19, 2010). In this proposed rule, based upon reconsideration of the primary...

  10. 75 FR 26225 - Adequacy Status of the Chicago, Illinois Area Submitted 8-Hour Ozone Redesignation and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-11

    ... budgets in our July 1, 2004, preamble starting at 69 FR 40038, and we used the information in these... Plans for Transportation Conformity Purposes AGENCY: Environmental Protection Agency (EPA). ACTION... conformity determinations. Illinois submitted a redesignation request and maintenance plan for the...

  11. 78 FR 34903 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... section 176(c) of the CAA. See the official release of the MOVES2010 emissions model (75 FR 9411-9414) for... source emissions for criteria pollutants, including precursors. Transportation plans and projects... highway emissions. EPA announced the release of MOVES2010 on March 2, 2010 (75 FR 9411). Use of the...

  12. Ozone

    SciTech Connect

    Not Available

    1988-06-01

    The author discusses the debate over whether concern about a hole in the ozone layer in Antarctic is real or science fiction. There is a growing consensus that efforts must be taken to protect the ozone layer. The issue now is not whether chlorofluorocarbons (CFCs) should be controlled and regulated but how much and how soon. The United States has urged that the production of dangerous CFCs, and any other chemicals that affect the ozone layer, be restricted immediately to current levels and that their use be reduced 95 percent over the next decade. The American position was too strong for many European nations and the Japanese. Negotiations at an international conference on the matter broke down. The breakdown is due in part to a more acute concern for environmental matters in the United States than exists in many countries. Meanwhile CFCs are linked to another environmental problem that equally threatens the world - the Greenhouse Effect. The earth is in a natural warming period, but man could be causing it to become even warmer. The Greenhouse Effect could have a catastrophic impact on mankind, although nothing has been proven yet.

  13. Ozone

    MedlinePlus

    ... reactive form of oxygen. In the upper atmosphere, ozone forms a protective layer that shields us from the sun’s ultraviolet rays. At ground level, ozone is a harmful air pollutant and a primary ...

  14. Ozone

    MedlinePlus

    Ozone is a gas. It can be good or bad, depending on where it is. "Good" ozone occurs naturally about 10 to 30 miles above ... the sun's ultraviolet rays. Part of the good ozone layer is gone. Man-made chemicals have destroyed ...

  15. Ozone trends in California`s South Coast Air Basin, 1976--1996

    SciTech Connect

    Cohanim, S.; Cassmassi, J.; Bassett, M.

    1998-12-31

    The South Coast Air Basin (Basin) of Southern California exhibits the worst air quality in the nation, as measured by the annual number of days exceeding the 1-hour National Ambient Air Quality Standard (NAAQS) for ozone. Hourly pollutant concentration data collected by the South Coast Air Quality Management District`s air monitoring network are compared to the existing 1-hour and new 8-hour federal ozone ambient air quality standards to depict ozone trends and compliance in the Basin. Results of trend analyses for the different areas of the Basin are presented for the 1-hour and 8-hour standards, and the relative stringency of the existing and new federal standards is examined. Based on an analysis of the effect of the recently adopted federal standard on ozone compliance in the Basin, ozone concentrations exceed the new federal 8-hour standard level more often than the existing 1-hour standard in most locations. However, examination of the trends in design values for the 1-hour and 8-hour ozone standards suggests that for most locations in the Basin the new standard probably should not be significantly more difficult to attain than the existing standard. The weather-adjusted ozone trend analysis in the Basin confirms the fact that the downtrends in ozone concentrations and number of days exceeding standards are real and independent of annual variation in weather. An analysis of weekday/weekend differences in exceedances for the existing 1-hour and new 8-hour ozone standards show a higher number of days exceeding both standards on weekends for most locations in the Basin, with differences being more evident in the 1990s than in the late 1970s and 1980s

  16. Tropospheric ozone in the Nisqually River Drainage, Mount Rainier National Park

    USGS Publications Warehouse

    Peterson, D.L.; Bowers, Darci

    1999-01-01

    We quantified the summertime distribution of tropospheric ozone in the topographically complex Nisqually River drainage of Mount Rainier National Park from 1994 to 1997. Passive ozone samplers were used along an elevational transect to measure weekly average ozone concentrations ranging from 570 m to 2040 m elevation. Weekly average ozone concentrations were positively correlated with elevation, with the highest concentrations consistently measured at the highest sampling site (Panorama Point). Weekly average ozone concentrations at Mount Rainier National Park are considerably higher than those in the Seattle-Tacoma metropolitan area to the west. The anthropogenic contribution to ozone within the Nisqually drainage was evaluated by comparing measurements at this location with measurements from a 'reference' site in the western Olympic Mountains. The comparison suggests there is a significant anthropogenic source of ozone reaching the Cascade Range via atmospheric transport from urban areas to the west. In addition. temporal (week to week) variation in ozone distribution is synchronous within the Nisqually drainage, which indicates that subregional patterns are detectable with weekly averages. The Nisqually drainage is likely the 'hot spot' for air pollution in Mount Rainier National Park. By using passive ozone samplers in this drainage in conjunction with a limited number of continuous analyzers, the park will have a robust monitoring approach for measuring tropospheric ozone over time and protecting vegetative and human health.

  17. A 4.8 hour periodicity in the spectra of Cyg X-3

    NASA Technical Reports Server (NTRS)

    Becker, R. H.; Robinson-Saba, J. L.; Boldt, E. A.; Holt, S. S.; Pravdo, S. H.; Serlemitsos, P. J.; Swank, J. H.

    1978-01-01

    The X-ray spectra from three observations of the X-ray binary Cyg X-3 by the cosmic X-ray spectroscopy experiment on OSO can be represented by power-law continua with strong iron line emission. Comparisons of spectra taken within the same observation at various phases of the 4.8 hour period reveal a relative excess of low energy X-ray emission near zero phase (i.e. the minimum) of the 4.8 hour modulation. In addition, the centroid of the line emission is observed to vary in phase with the 4.8 hour cycle. The possibility of persistent thermal X-ray emission from material surrounding the binary system is introduced in an effort to account for the observed effects.

  18. Characterization of ambient ozone levels in the Great Smoky Mountains National Park

    SciTech Connect

    Mueller, S.F.

    1994-04-01

    Ambient ozone data collected at two sites in the Great Smoky Mountains National Park (GSMNP) are summarized and compared with data from an urban and a low-elevation rural site. The ozone climatology in the park is found to be similar to that of other remote sites in the southern Appalachian Mountain region. As expected, terrain elevation identified as a major factor influencing local ozone levels. Episodes of high ozone concentrations ({ge} 90 ppb) in the park are shown to be primarily attributable to the transport of ozone into the park from outside. Backward air trajectories computed for high-ozone episodes in the GSMNP reveal that no preferred source regions exist, although some episodes appear to be associated with transport from urban areas. 8 refs., 7 figs., 2 tabs.

  19. Spatial distribution of tropospheric ozone in national parks of California: interpretation of passive-sampler data.

    PubMed

    Ray, J D

    2001-09-28

    The National Park Service (NPS) has tested and used passive ozone samplers for several years to get baseline values for parks and to determine the spatial variability within parks. Experience has shown that the Ogawa passive samplers can provide +/-10% accuracy when used with a quality assurance program consisting of blanks, duplicates, collocated instrumentation, and a standard operating procedure that carefully guides site operators. Although the passive device does not meet EPA criteria as a certified method (mainly, that hourly values be measured), it does provide seasonal summed values of ozone. The seasonal ozone concentrations from the passive devices can be compared to other monitoring to determine baseline values, trends, and spatial variations. This point is illustrated with some kriged interpolation maps of ozone statistics. Passive ozone samplers were used to get elevational gradients and spatial distributions of ozone within a park. This was done in varying degrees at Mount Rainier, Olympic, Sequoia-Kings Canyon, Yosemite, Joshua Tree, Rocky Mountain, and Great Smoky Mountains national parks. The ozone has been found to vary by factors of 2 and 3 within a park when average ozone is compared between locations. Specific examples of the spatial distributions of ozone in three parks within California are given using interpolation maps. Positive aspects and limitations of the passive sampling approach are presented.

  20. 77 FR 30087 - Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... Columbia EPA Environmental Protection Agency FR Federal Register NAAQS National Ambient Air Quality... Environmental protection, Air pollution control, National parks, Wilderness areas. Dated: April 30, 2012. Lisa P... for the 2008 Ozone National Ambient Air Quality Standards; Implementation of the 2008 National...

  1. A survey of ozone concentrations in rural western Utah: unexpected results and spatial heterogeneity from 2010-2013

    NASA Astrophysics Data System (ADS)

    Arens, S. J.; Harper, K.

    2013-12-01

    Ozone concentrations and meteorological variables were monitored at eleven sites in rural western Utah during late spring through summer of 2010-2013 to determine regional background concentrations of ozone and to determine attainment or nonattainment of the ozone National Ambient Air Quality Standard (NAAQS). Ozone concentrations have been monitored along the Wasatch Front of Utah (Logan, Ogden, Salt Lake City and Provo) for 30 years by the Utah Division of Air Quality (DAQ), but no ozone data from outside the cities of Wasatch Front existed prior to 2010. All rural sites, except Badger Springs, west of St. George, UT, were in attainment of the ozone NAAQS, which is 75 ppb averaged over 8 hours. However, ozone concentrations were higher than expected at seven of the eleven sites. All eleven sites were located in either small rural towns or uninhabited areas of western Utah, which were distant from anthropogenic emissions of ozone precursors. In 2010, ozone concentrations were relatively low along the Wasatch Front of Utah. Ozone concentrations exceeded 65 ppb for one day at three of four rural sites. Ozone concentrations at two of the four sites were generally in the range of expected rural ozone concentrations of 50-60 ppb. Ozone concentrations during 2011-2012 were higher throughout Utah compared to 2010. In 2011, 8-hour ozone concentrations exceeded 70 ppb for at least one day at four of five sites. The maximum 8-hour ozone concentration was 78 ppb, observed at Lytle Ranch, west of St. George, UT. Ozone concentrations at only one rural Utah site were in the expected range of 50-60 ppb. Ozone concentrations during 2012 were the highest observed during the four years of the study with 8-hour ozone concentrations exceeding 75 ppb at three of five rural sites and exceeding 70 ppb for at least four days at four of five sites. Although data collected was not considered regulatory by the EPA, the ozone NAAQS was exceeded at Badger Springs in southwestern Utah. Ozone

  2. PREDICTING THE IMPACT OF TROPOSPHERIC OZONE ON ECOLOGICAL RESOURCES FOR SETTING NATIONAL AMBIENT AIR QUALITY STANDARDS

    EPA Science Inventory

    The Clean Air Act provides for establishing National Ambient Air Quality Standards (NAAQS) to protect public welfare (including crops, forests, ecosystems, and soils) from adverrse effects of air pollutants, including tropospheric ozone. The formulation of policies is science-bas...

  3. A national fine spatial scale land-use regression model for ozone.

    PubMed

    Kerckhoffs, Jules; Wang, Meng; Meliefste, Kees; Malmqvist, Ebba; Fischer, Paul; Janssen, Nicole A H; Beelen, Rob; Hoek, Gerard

    2015-07-01

    Uncertainty about health effects of long-term ozone exposure remains. Land use regression (LUR) models have been used successfully for modeling fine scale spatial variation of primary pollutants but very limited for ozone. Our objective was to assess the feasibility of developing a national LUR model for ozone at a fine spatial scale. Ozone concentrations were measured with passive samplers at 90 locations across the Netherlands (19 regional background, 36 urban background, 35 traffic). All sites were measured simultaneously during four 2-weekly campaigns spread over the seasons. LUR models were developed for the summer average as the primary exposure and annual average using predictor variables obtained with Geographic Information Systems. Summer average ozone concentrations varied between 32 and 61 µg/m(3). Ozone concentrations at traffic sites were on average 9 µg/m(3) lower compared to regional background sites. Ozone correlated highly negatively with nitrogen dioxide and moderately with fine particles. A LUR model including small-scale traffic, large-scale address density, urban green and a region indicator explained 71% of the spatial variation in summer average ozone concentrations. Land use regression modeling is a promising method to assess ozone spatial variation, but the high correlation with NO2 limits application in epidemiology.

  4. Incidence of ozone symptoms on vegetation within a National Wildlife Refuge in New Jersey, USA.

    PubMed

    Davis, Donald D; Orendovici, Teodora

    2006-10-01

    During 1993-1996 and 2001-2003, we evaluated the percentage of plants (incidence) exhibiting ozone-induced foliar symptoms on vegetation within a National Wildlife Refuge located along the Atlantic Ocean coast of New Jersey, USA. Incidence varied among plant species and years. Bioindicator plants most sensitive to ozone, across all years, included native common milkweed (Asclepias syriaca) and wild grape (Vitis spp.), as well as introduced tree-of-heaven (Ailanthus altissima). Less sensitive bioindicators included Virginia creeper (Parthenocissus quinquefolia) and winged sumac (Rhus coppolina). Black cherry (Prunus serotina) and sassafras (Sassafras albidum) were least sensitive. The greatest incidence of ozone symptoms, across all plant species, occurred in 1996, followed by 2001>1995>1994>1993>2003>2002. A model was developed that showed a statistically significant relationship between incidence of ozone symptoms and the following parameters: plant species, Palmer Drought Severity Index, and the interaction of W126 x N100 measures of ambient ozone.

  5. Incidence of ozone symptoms on vegetation within a National Wildlife Refuge in New Jersey, USA.

    PubMed

    Davis, Donald D; Orendovici, Teodora

    2006-10-01

    During 1993-1996 and 2001-2003, we evaluated the percentage of plants (incidence) exhibiting ozone-induced foliar symptoms on vegetation within a National Wildlife Refuge located along the Atlantic Ocean coast of New Jersey, USA. Incidence varied among plant species and years. Bioindicator plants most sensitive to ozone, across all years, included native common milkweed (Asclepias syriaca) and wild grape (Vitis spp.), as well as introduced tree-of-heaven (Ailanthus altissima). Less sensitive bioindicators included Virginia creeper (Parthenocissus quinquefolia) and winged sumac (Rhus coppolina). Black cherry (Prunus serotina) and sassafras (Sassafras albidum) were least sensitive. The greatest incidence of ozone symptoms, across all plant species, occurred in 1996, followed by 2001>1995>1994>1993>2003>2002. A model was developed that showed a statistically significant relationship between incidence of ozone symptoms and the following parameters: plant species, Palmer Drought Severity Index, and the interaction of W126 x N100 measures of ambient ozone. PMID:16458398

  6. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment... Air Quality Standards for Ozone 1. General (a) This appendix explains the data handling conventions... air quality standards for ozone (O3) specified in § 50.15 are met at an ambient O3 air...

  7. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment... Air Quality Standards for Ozone 1. General (a) This appendix explains the data handling conventions... air quality standards for ozone (O3) specified in § 50.15 are met at an ambient O3 air...

  8. Estimating contribution of wildland fires to ambient ozone levels in National Parks in the Sierra Nevada, California.

    PubMed

    Preisler, Haiganoush K; Zhong, Shiyuan Sharon; Esperanza, Annie; Brown, Timothy J; Bytnerowicz, Andrzej; Tarnay, Leland

    2010-03-01

    Data from four continuous ozone and weather monitoring sites operated by the National Park Service in Sierra Nevada, California, are used to develop an ozone forecasting model and to estimate the contribution of wildland fires on ambient ozone levels. The analyses of weather and ozone data pointed to the transport of ozone precursors from the Central Valley as an important source of pollution in these National Parks. Comparisons of forecasted and observed values demonstrated that accurate forecasts of next-day hourly ozone levels may be achieved by using a time series model with historic averages, expected local weather and modeled PM values as explanatory variables. Results on fire smoke influence indicated occurrence of significant increases in average ozone levels with increasing fire activity. The overall effect on diurnal ozone values, however, was small when compared with the amount of variability attributed to sources other than fire.

  9. Estimating contribution of wildland fires to ambient ozone levels in National Parks in the Sierra Nevada, California.

    PubMed

    Preisler, Haiganoush K; Zhong, Shiyuan Sharon; Esperanza, Annie; Brown, Timothy J; Bytnerowicz, Andrzej; Tarnay, Leland

    2010-03-01

    Data from four continuous ozone and weather monitoring sites operated by the National Park Service in Sierra Nevada, California, are used to develop an ozone forecasting model and to estimate the contribution of wildland fires on ambient ozone levels. The analyses of weather and ozone data pointed to the transport of ozone precursors from the Central Valley as an important source of pollution in these National Parks. Comparisons of forecasted and observed values demonstrated that accurate forecasts of next-day hourly ozone levels may be achieved by using a time series model with historic averages, expected local weather and modeled PM values as explanatory variables. Results on fire smoke influence indicated occurrence of significant increases in average ozone levels with increasing fire activity. The overall effect on diurnal ozone values, however, was small when compared with the amount of variability attributed to sources other than fire. PMID:19914752

  10. When do high ozone events occur in Great Smoky Mountains National Park?

    SciTech Connect

    Neufeld, H.; Joseph, D.

    1995-12-31

    In this paper the authors compare ozone dynamics between high and low elevation sites in Great Smoky Mountains National Park for the years 1988--1994. They have shown in earlier studies that high elevation sites have flatter diurnal ozone profiles, and greater total exposures, than low elevation sites, due mainly to elevated ozone concentrations in the nighttime hours. If they define an ozone episode as any period in which the hourly average meets or exceeds 60 ppb, then they find that at the low elevation site, Twin Creeks, 80% of the peak ozone events occur during daylight hours (most between 2--4 pm), whereas at the high elevation site (Cove Mt.), over 60% of the episodes occur at night. At Cove Mt., lower concentrations (40--60 ppb) occur with almost equal frequency at any time. Cove Mt. also has 5X as many episodes, which last up to 2X as long as those at Twin Creeks. Respite periods (ozone concentrations < 60 ppb) are 3X as common at Cove Mt., but last only 1/5th as long as those at Twin Creeks, such that the high elevation site has 41% less respite time between episodes. These patterns have implications for plant response, since plants take up ozone mainly when their stomata are open. Thus, even though ozone exposures are greater at high elevations, and respite times less, the fact that acutely high concentrations of ozone are limited to periods when stomata are normally closed, means that the ozone dose to the leaf (amount actually absorbed) may be lower than expected.

  11. 75 FR 2938 - National Ambient Air Quality Standards for Ozone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ... information provided, unless the comment includes information claimed to be Confidential Business Information....gov/ttn/naaqs/standards/ozone/s_o3_cr_fr.html prior to the hearing. Verbatim transcripts of the... for this rulemaking. The public is invited to submit comments or identify peer-reviewed studies...

  12. 77 FR 35285 - Approval of Air Quality Implementation Plan; Arizona; Attainment Plan for 1997 8-Hour Ozone Standard

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-13

    ... Order Reviews I. Proposed Action On April 11, 2012 (70 FR 21690), EPA proposed to approve the ``Eight... Budget under Executive Order 12866 (58 FR 51735, October 4, 1993); Does not impose an information...); Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August...

  13. 76 FR 3840 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard for the Delaware...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-21

    ... November 9, 2010 (75 FR 68736), EPA published a notice of proposed rulemaking (NPR) for the States. The NPR... Executive Order Reviews A. General Requirements Under Executive Order 12866 (58 FR 51735, October 4, 1993...'' (66 FR 28355, May 22, 2001). This action merely approves state law as meeting Federal requirements...

  14. 76 FR 3838 - Approval and Promulgation of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-21

    ... attainment date be extended to June 15, 2011. On November 9, 2010 (75 FR 68733), EPA proposed to approve New...).'' IV. Statutory and Executive Order Reviews Under Executive Order 12866 (58 FR 51735, October 4, 1993...'' (66 FR 28355 (May 22, 2001)). This action merely finds that an area has qualified for a...

  15. 75 FR 68736 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard for the Delaware...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    ...'' subject to review by the Office of Management and Budget under Executive Order 12866 (58 FR 51735, October... Executive Order 13132 (64 FR 43255, August 10, 1999); Is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997); ] Is...

  16. 75 FR 43069 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard in the Baltimore...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use'' (66 FR 28355 (May 22... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION... Baltimore Moderate Nonattainment Area AGENCY: Environmental Protection Agency (EPA). ACTION: Direct...

  17. 78 FR 34906 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Lima 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... the following methods: 1. www.regulations.gov : Follow the on-line instructions for submitting....regulations.gov , including any personal information provided, unless the comment includes information claimed....regulations.gov or email. The www.regulations.gov Web site is an ``anonymous access'' system, which means...

  18. 75 FR 43114 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard in the Baltimore...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... the following methods: A. http://www.regulations.gov . Follow the on-line instructions for submitting... the use of special characters, any form of encryption, and be free of any defects or viruses....

  19. 75 FR 16456 - Adequacy Status of the Beaumont-Port Arthur, TX Maintenance Plan; 8-Hour Ozone Motor Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-01

    ...; Transportation Conformity Rule Amendments: Response to Court Decision and Additional Rule Changes'' (69 FR 40004... been made, pursuant to 40 CFR 93.104(e). See, 73 FR 4419 (January 24, 2008). Authority: 42 U.S.C. 7401... motor vehicle emissions budgets (MVEB) in the Beaumont-Port Arthur, Texas (BPA) Redesignation...

  20. 78 FR 34965 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Lima 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... arrangements should be made for deliveries of boxed information. The Regional Office official hours of business... second comment period. Any parties interested in commenting on this action should do so at this...

  1. 75 FR 55977 - Adequacy Status of the Knoxville, TN 1997 8-Hour Ozone Maintenance Plan Motor Vehicle Emission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-15

    ... Additional Rule Changes'' (69 FR 40004). Please note that an adequacy review is separate from EPA's... made, pursuant to 40 CFR 93.104(e). See 73 FR 4419 (January 24, 2008). Authority: 42 U.S.C. 7401 et seq... Vehicle Emission Budgets for Transportation Conformity Purposes AGENCY: Environmental Protection...

  2. 76 FR 28223 - Adequacy Status of the Baton Rouge, Louisiana Maintenance Plan 8-Hour Ozone Motor Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-16

    ... Additional Rule Changes'' (69 FR 40004). Please note that an adequacy review is separate from EPA's... the new MVEB if the demonstration has not already been made, pursuant to 40 CFR 93.104(e). See, 73 FR... Emission Budgets for Transportation Conformity Purposes AGENCY: Environmental Protection Agency...

  3. 78 FR 7429 - Adequacy Status of the Dallas-Fort Worth, TX Reasonable Further Progress 8-Hour Ozone Motor...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-01

    ...: Response to Court Decision and Additional Rule Changes'' (69 FR 40004). Please note that an adequacy review..., pursuant to 40 CFR 93.104(e). See, 73 FR 4419 (January 24, 2008). Authority: 42 U.S.C. 7401 et seq. Dated... Vehicle Emission Budgets for Transportation Conformity Purposes AGENCY: Environmental Protection...

  4. 75 FR 9893 - Adequacy Determination for the Denver Metro Area and North Front Range 8-Hour Ozone Attainment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ... North Front Range Metropolitan Planning Organization (NFR MPO), the Colorado Department of...) which was promulgated August 15, 1997 (see 62 FR 43780). We described our process for determining the adequacy of submitted SIP MVEBs in our July 1, 2004 Transportation Conformity Rule Amendments (see 69...

  5. 77 FR 21690 - Approval and Promulgation of Air Quality Implementation Plan for 1997 8-Hour Ozone Standard; Arizona

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-11

    .../Projects/Project.asp?CMSID2=1120 &MID=Environmental%20Programs. In June 2007, the United States Court of... documentation in their submittals explaining how the emissions data were calculated. See 70 FR 71612 (Nov. 29... is proposing to approve revisions to the Arizona state implementation plan (SIP) that...

  6. 40 CFR 52.1342 - Control strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-IL) metropolitan 1997 8-hour ozone nonattainment area has attained the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends the requirements for this area to submit an attainment... measures, and other plan elements related to attainment of the standards for as long as the area...

  7. 77 FR 73570 - Approval and Promulgation of Implementation Plans; New Jersey and New York Ozone Attainment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-11

    ... 8-hour ozone implementation rule, published on November 29, 2005 (70 FR 71612) (Phase 2 Rule... of the 2008 ozone NAAQS. \\2\\ See 73 FR 16436; March 27, 2008. For a detailed explanation of the... to address the requirements of the 1997 8-hour ozone standard: On July 17, 2008 (73 FR 41068),...

  8. 78 FR 52893 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-27

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 50, 51, 70 and 71 RIN 2060-AR34 Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements Correction In proposed rule...

  9. Bayesian Maximum Entropy Integration of Ozone Observations and Model Predictions: A National Application.

    PubMed

    Xu, Yadong; Serre, Marc L; Reyes, Jeanette; Vizuete, William

    2016-04-19

    To improve ozone exposure estimates for ambient concentrations at a national scale, we introduce our novel Regionalized Air Quality Model Performance (RAMP) approach to integrate chemical transport model (CTM) predictions with the available ozone observations using the Bayesian Maximum Entropy (BME) framework. The framework models the nonlinear and nonhomoscedastic relation between air pollution observations and CTM predictions and for the first time accounts for variability in CTM model performance. A validation analysis using only noncollocated data outside of a validation radius rv was performed and the R(2) between observations and re-estimated values for two daily metrics, the daily maximum 8-h average (DM8A) and the daily 24-h average (D24A) ozone concentrations, were obtained with the OBS scenario using ozone observations only in contrast with the RAMP and a Constant Air Quality Model Performance (CAMP) scenarios. We show that, by accounting for the spatial and temporal variability in model performance, our novel RAMP approach is able to extract more information in terms of R(2) increase percentage, with over 12 times for the DM8A and over 3.5 times for the D24A ozone concentrations, from CTM predictions than the CAMP approach assuming that model performance does not change across space and time.

  10. Bayesian Maximum Entropy Integration of Ozone Observations and Model Predictions: A National Application.

    PubMed

    Xu, Yadong; Serre, Marc L; Reyes, Jeanette; Vizuete, William

    2016-04-19

    To improve ozone exposure estimates for ambient concentrations at a national scale, we introduce our novel Regionalized Air Quality Model Performance (RAMP) approach to integrate chemical transport model (CTM) predictions with the available ozone observations using the Bayesian Maximum Entropy (BME) framework. The framework models the nonlinear and nonhomoscedastic relation between air pollution observations and CTM predictions and for the first time accounts for variability in CTM model performance. A validation analysis using only noncollocated data outside of a validation radius rv was performed and the R(2) between observations and re-estimated values for two daily metrics, the daily maximum 8-h average (DM8A) and the daily 24-h average (D24A) ozone concentrations, were obtained with the OBS scenario using ozone observations only in contrast with the RAMP and a Constant Air Quality Model Performance (CAMP) scenarios. We show that, by accounting for the spatial and temporal variability in model performance, our novel RAMP approach is able to extract more information in terms of R(2) increase percentage, with over 12 times for the DM8A and over 3.5 times for the D24A ozone concentrations, from CTM predictions than the CAMP approach assuming that model performance does not change across space and time. PMID:26998937

  11. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hour standards are codified in 40 CFR part 81. (c) EPA's authority under paragraph (b) of this section... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  12. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hour standards are codified in 40 CFR part 81. ... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  13. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hour standards are codified in 40 CFR part 81. ... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  14. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hour standards are codified in 40 CFR part 81. (c) EPA's authority under paragraph (b) of this section... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  15. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hour standards are codified in 40 CFR part 81. ... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  16. Measurement, modeling, and analysis of nonmethane hydrocarbons and ozone in the southeast United States national parks

    NASA Astrophysics Data System (ADS)

    Kang, Daiwen

    In this research, the sources, distributions, transport, ozone formation potential, and biogenic emissions of VOCs are investigated focusing on three Southeast United States National Parks: Shenandoah National Park, Big Meadows site (SHEN), Great Smoky Mountains National Park at Cove Mountain (GRSM) and Mammoth Cave National Park (MACA). A detailed modeling analysis is conducted using the Multiscale Air Quality SImulation Platform (MAQSIP) focusing on nonmethane hydrocarbons and ozone characterized by high O3 surface concentrations. Nine emissions perturbation using the Multiscale Air Quality SImulation Platform (MAQSIP) focusing on nonmethane hydrocarbons and ozone characterized by high O 3 surface concentrations. In the observation-based analysis, source classification techniques based on correlation coefficient, chemical reactivity, and certain ratios were developed and applied to the data set. Anthropogenic VOCs from automobile exhaust dominate at Mammoth Cave National Park, and at Cove Mountain, Great Smoky Mountains National Park, while at Big Meadows, Shenandoah National Park, the source composition is complex and changed from 1995 to 1996. The dependence of isoprene concentrations on ambient temperatures is investigated, and similar regressional relationships are obtained for all three monitoring locations. Propylene-equivalent concentrations are calculated to account for differences in reaction rates between the OH and individual hydrocarbons, and to thereby estimate their relative contributions to ozone formation. Isoprene fluxes were also estimated for all these rural areas. Model predictions (base scenario) tend to give lower daily maximum O 3 concentrations than observations by 10 to 30%. Model predicted concentrations of lumped paraffin compounds are of the same order of magnitude as the observed values, while the observed concentrations for other species (isoprene, ethene, surrogate olefin, surrogate toluene, and surrogate xylene) are usually an

  17. Overview of the national precision database for ozone

    SciTech Connect

    Mikel, D.K.

    1999-07-01

    One of the most important ambient air monitoring quality assurance indicators is the precision test. Code of Federal Regulation Title 40, Section 58 (40 CFR 58) Appendix A1 states that all automated analyzers must have precision tests performed at least once every two weeks. Precision tests can be the best indicator of quality of data for the following reasons: Precision tests are performed once every two weeks. There are approximately 24 to 26 tests per year per instrument. Accuracy tests (audits) usually occur only 1--2 times per year. Precision tests and the subsequent statistical tests can be used to calculate the bias in a set of data. Precision test are used to calculate 95% confidence (probability) limits for the data set. This is important because the confidence of any data point can be determined. If the authors examine any exceedances or near exceedances of the ozone NAAQS, the confidence limits must be examined as well. Precision tests are performed by the monitoring staff and the precision standards are certified against the internal agency primary standards. Precision data are submitted by all state and local agencies that are required to submit criteria pollutant data to the Aerometric and Information Retrieval System (AIRS) database. This subset of the AIRS database is named Precision and Accuracy Retrieval Systems (PARS). In essence, the precision test is an internally performed test performed by the agency collecting and reporting the data.

  18. PREDICTING THE IMPACT OF TROPOSPHERIC OZONE ON PLANTS AND ECOSYSTEMS AS A BASIS FOR SETTING NATIONAL AIR QUALITY STANDARDS

    EPA Science Inventory

    The Clean Air Act provides for establishing National Ambient Air Quality Standards (NAAQS) to protect public welfare (including crops, forests, ecosystems, and soils) from adverse effects of air pollutants, including tropospheric ozone. The formulation of policies is science-base...

  19. 40 CFR 51.913 - How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false How do the section 182(f) NOX exemption... How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS? (a) A person may petition the Administrator for an exemption from NOX obligations under section 182(f) for any...

  20. 40 CFR 51.913 - How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 2 2013-07-01 2013-07-01 false How do the section 182(f) NOX exemption... How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS? (a) A person may petition the Administrator for an exemption from NOX obligations under section 182(f) for any...

  1. A direct sensitivity approach to predict hourly ozone resulting from compliance with the National Ambient Air Quality Standard.

    PubMed

    Simon, Heather; Baker, Kirk R; Akhtar, Farhan; Napelenok, Sergey L; Possiel, Norm; Wells, Benjamin; Timin, Brian

    2013-03-01

    In setting primary ambient air quality standards, the EPA's responsibility under the law is to establish standards that protect public health. As part of the current review of the ozone National Ambient Air Quality Standard (NAAQS), the US EPA evaluated the health exposure and risks associated with ambient ozone pollution using a statistical approach to adjust recent air quality to simulate just meeting the current standard level, without specifying emission control strategies. One drawback of this purely statistical concentration rollback approach is that it does not take into account spatial and temporal heterogeneity of ozone response to emissions changes. The application of the higher-order decoupled direct method (HDDM) in the community multiscale air quality (CMAQ) model is discussed here to provide an example of a methodology that could incorporate this variability into the risk assessment analyses. Because this approach includes a full representation of the chemical production and physical transport of ozone in the atmosphere, it does not require assumed background concentrations, which have been applied to constrain estimates from past statistical techniques. The CMAQ-HDDM adjustment approach is extended to measured ozone concentrations by determining typical sensitivities at each monitor location and hour of the day based on a linear relationship between first-order sensitivities and hourly ozone values. This approach is demonstrated by modeling ozone responses for monitor locations in Detroit and Charlotte to domain-wide reductions in anthropogenic NOx and VOCs emissions. As seen in previous studies, ozone response calculated using HDDM compared well to brute-force emissions changes up to approximately a 50% reduction in emissions. A new stepwise approach is developed here to apply this method to emissions reductions beyond 50% allowing for the simulation of more stringent reductions in ozone concentrations. Compared to previous rollback methods, this

  2. Airborne Observations of Ozone and Other Trace Gases Upwind of National Parks in California and Nevada

    NASA Technical Reports Server (NTRS)

    Iraci, Laura T.

    2016-01-01

    The Alpha Jet Atmospheric eXperiment (AJAX) is a research project based at Moffett Field, CA, which collects airborne measurements of ozone, carbon dioxide, methane, water vapor, and formaldehyde, as well as 3-D winds, temperature, pressure, and location. Since its first science flight in 2011, AJAX has developed a wide a variety of mission types, combining vertical profiles (from approximately 8 km to near surface), boundary layer legs, and plume sampling as needed. With an ongoing five-year data set, the team has sampled over 160 vertical profiles, a dozen wildfires, and numerous stratospheric ozone intrusions. Our largest data collection includes 55 vertical profiles at Railroad Valley, NV, approximately 100 miles southwest of Great Basin National Park, and many of those flights include comparisons to surface monitors in the Nevada Rural Ozone Initiative network. We have also collected a smaller set of measurements northwest of Joshua Tree National Park, and are looking to develop partnerships that can put this data to use to assess or improve air quality in nearby Parks. AJAX also studies the plumes emitted by wildfires in California, as most emissions inventories are based on prescribed fires. We have sampled a dozen fires, and results will be presented from several, including the Rim (2013), Soberanes and Cedar (2016) Fires.

  3. 40 CFR 52.2125 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends the... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: Ozone. 52.2125... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the...

  4. 40 CFR 52.1779 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends the... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Ozone. 52.1779... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the...

  5. 40 CFR 52.2125 - Control strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends the... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: Ozone. 52.2125... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the...

  6. 40 CFR 52.1779 - Control strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends the... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Ozone. 52.1779... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the...

  7. 40 CFR 52.2125 - Control strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends the... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: Ozone. 52.2125... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the...

  8. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS Pt. 50, App. P Appendix P...

  9. Cerebral blood flow determination within the first 8 hours of cerebral infarction using stable xenon-enhanced computed tomography

    SciTech Connect

    Hughes, R.L.; Yonas, H.; Gur, D.; Latchaw, R.

    1989-06-01

    Cerebral blood flow mapping with stable xenon-enhanced computed tomography (Xe/CT) was performed in conjunction with conventional computed tomography (CT) within the first 8 hours after the onset of symptoms in seven patients with cerebral infarction. Six patients had hemispheric infarctions, and one had a progressive brainstem infarction. Three patients with very low (less than 10 ml/100 g/min) blood flow in an anatomic area appropriate for the neurologic deficit had no clinical improvement by the time of discharge from the hospital; follow-up CT scans of these three patients confirmed infarction in the area of very low blood flow. Three patients with moderate blood flow reductions (15-45 ml/100 g/min) in the appropriate anatomic area had significant clinical improvement from their initial deficits and had normal follow-up CT scans. One patient studied 8 hours after stroke had increased blood flow (hyperemia) in the appropriate anatomic area and made no clinical recovery.

  10. A direct sensitivity approach to predict hourly ozone resulting from compliance with the National Ambient Air Quality Standard.

    PubMed

    Simon, Heather; Baker, Kirk R; Akhtar, Farhan; Napelenok, Sergey L; Possiel, Norm; Wells, Benjamin; Timin, Brian

    2013-03-01

    In setting primary ambient air quality standards, the EPA's responsibility under the law is to establish standards that protect public health. As part of the current review of the ozone National Ambient Air Quality Standard (NAAQS), the US EPA evaluated the health exposure and risks associated with ambient ozone pollution using a statistical approach to adjust recent air quality to simulate just meeting the current standard level, without specifying emission control strategies. One drawback of this purely statistical concentration rollback approach is that it does not take into account spatial and temporal heterogeneity of ozone response to emissions changes. The application of the higher-order decoupled direct method (HDDM) in the community multiscale air quality (CMAQ) model is discussed here to provide an example of a methodology that could incorporate this variability into the risk assessment analyses. Because this approach includes a full representation of the chemical production and physical transport of ozone in the atmosphere, it does not require assumed background concentrations, which have been applied to constrain estimates from past statistical techniques. The CMAQ-HDDM adjustment approach is extended to measured ozone concentrations by determining typical sensitivities at each monitor location and hour of the day based on a linear relationship between first-order sensitivities and hourly ozone values. This approach is demonstrated by modeling ozone responses for monitor locations in Detroit and Charlotte to domain-wide reductions in anthropogenic NOx and VOCs emissions. As seen in previous studies, ozone response calculated using HDDM compared well to brute-force emissions changes up to approximately a 50% reduction in emissions. A new stepwise approach is developed here to apply this method to emissions reductions beyond 50% allowing for the simulation of more stringent reductions in ozone concentrations. Compared to previous rollback methods, this

  11. Response of macaque bronchiolar epithelium to ambient concentrations of ozone

    SciTech Connect

    Harkema, J.R.; Plopper, C.G.; Hyde, D.M.; St. George, J.A.; Wilson, D.W.; Dungworth, D.L. )

    1993-09-01

    Recently, we reported that exposure to ambient concentrations of ozone, near the U.S. National Ambient Air Quality Standard (0.12 ppm), induced significant nasal epithelial lesions in a non-human primate, the bonnet monkey. The present study defines the effects of ambient concentrations of ozone on the surface epithelium lining respiratory bronchioles and on the underlying bronchiolar interstitium in these same monkeys. Bonnet monkeys were exposed to filtered air or to 0.15 or 0.30 ppm ozone 8 hours/day for 6 or 90 days. At the end of exposures, monkeys were anesthetized and killed by exsanguination. Microdissected bronchiolar airways of infusion-fixed lungs were evaluated morphometrically by light microscopy and quantitatively by scanning and transmission electron microscopy for ozone-induced epithelial changes. Hyperplasia of nonciliated, cuboidal epithelial cells and intraluminal accumulation of macrophages characterized ozone-induced lesions in respiratory bronchioles. There were no significant differences in epithelial thickness or cell numbers among ozone-exposed groups. Ozone-exposed epithelium was composed of 80% cuboidal and 20% squamous cells compared with 40% cuboidal and 60% squamous cells in filtered air controls. In addition, the arithmetic mean thickness of the surface epithelium, a measure of tissue mass per unit area of basal lamina, was significantly increased in all of the ozone-exposed groups. The number of cuboidal epithelial cells per surface area of basal lamina was increased above control values by 780% after 6 days exposure to 0.15 ppm, 777% after 90 days to 0.15 ppm, and 996% after 90 days exposure to 0.30 ppm. There was also a significant ozone-induced increase in the thickness of the bronchiolar interstitium that was due to an increase in both cellular and acellular components.

  12. 77 FR 8197 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: Nonattainment Area...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... set at a more stringent level. \\1\\ See 73 FR 16436. \\2\\ The secondary ozone standard, designed to... 1-hour ozone NAAQS, see 56 FR 56694. \\8\\ See 40 CFR Appendix I. \\9\\ Referred to as the Phase 1 Rule... the 1997 ozone NAAQS. (See 69 FR 23954). The Phase 1 rule also established comprehensive...

  13. 78 FR 44485 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ... for Ozone: State Implementation Plan Requirements AGENCY: Environmental Protection Agency (EPA... Standards for Ozone: State Implementation Plan Requirements'' (June 6, 2013). The EPA is extending the...) and nitrogen oxides (NO X )) that contribute to ground-level ozone formation. B. What should...

  14. A Direct sensitivity approach to predict hourly ozone resulting from compliance with the National Ambient Air Quality Standard

    EPA Science Inventory

    In setting primary ambient air quality standards, the EPA’s responsibility under the law is to establish standards that protect public health. As part of the current review of the ozone National Ambient Air Quality Standard (NAAQS), the US EPA evaluated the health exposure and ...

  15. Ozone trends in Great Smoky Mountains National Park over the past two decades: Implications for plants and ecosystems

    EPA Science Inventory

    Hourly ozone data from five sampling locations in Great Smoky Mountains National Park and one low elevation location adjacent to the Park in NC were analyzed over the period 1989 to 2012 for diurnal and season trends. Sampling locations spanned an elevational range from 564 m at...

  16. Suomi National Polar-orbiting Partnership Ozone Mapping Profiler Suite Nadir instruments in-flight performance

    NASA Astrophysics Data System (ADS)

    Pan, Chunhui; Flynn, Larry; Wu, Xiangqian; Buss, Rich

    2014-01-01

    This paper analyzes the in-flight performance of the Suomi National Polar-orbiting Partnership Ozone Mapping & Profiling Suite (OMPS) nadir instruments and evaluates sensors' on-orbit calibrations after sensors' two-year operation. All uncertainty values quoted in this paper are 1-σ values unless stated otherwise. With the data collected from in-flight nominal calibration, our results have demonstrated that sensor performance complies with the system specifications in most cases. The largest term in the wavelength-dependent albedo calibration uncertainty for Nadir Mapper is the cross-track position difference effect of 2.5%. Final adjustments of stray light and wavelength variation are still being made to optimize OMPS sensor data records before reaching the validation mature level.

  17. 78 FR 34177 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-06

    ... FR 16436. \\2\\ For a detailed explanation of the calculation of the 3-year 8-hour average, see 40 CFR.... \\6\\ 77 FR 30160, May 21, 2012. In this action, the EPA proposes a rule to address the steps states... Recovery: In a separate Federal Register notice (77 FR 28772; May 16, 2012), the EPA determined...

  18. Impact of climate change on ambient ozone level and mortality in southeastern United States.

    PubMed

    Chang, Howard H; Zhou, Jingwen; Fuentes, Montserrat

    2010-07-01

    There is a growing interest in quantifying the health impacts of climate change. This paper examines the risks of future ozone levels on non-accidental mortality across 19 urban communities in Southeastern United States. We present a modeling framework that integrates data from climate model outputs, historical meteorology and ozone observations, and a health surveillance database. We first modeled present-day relationships between observed maximum daily 8-hour average ozone concentrations and meteorology measured during the year 2000. Future ozone concentrations for the period 2041 to 2050 were then projected using calibrated climate model output data from the North American Regional Climate Change Assessment Program. Daily community-level mortality counts for the period 1987 to 2000 were obtained from the National Mortality, Morbidity and Air Pollution Study. Controlling for temperature, dew-point temperature, and seasonality, relative risks associated with short-term exposure to ambient ozone during the summer months were estimated using a multi-site time series design. We estimated an increase of 0.43 ppb (95% PI: 0.14-0.75) in average ozone concentration during the 2040's compared to 2000 due to climate change alone. This corresponds to a 0.01% increase in mortality rate and 45.2 (95% PI: 3.26-87.1) premature deaths in the study communities attributable to the increase in future ozone level.

  19. Are the elements of the proposed ozone National Ambient Air Quality Standards informed by the best available science?

    PubMed

    Goodman, Julie E; Sax, Sonja N; Lange, Sabine; Rhomberg, Lorenz R

    2015-06-01

    The United States Environmental Protection Agency (US EPA) issues National Ambient Air Quality Standards (NAAQS) for six criteria pollutants, including ozone. Each standard has four elements: an indicator, level, averaging time, and form. Ozone levels (i.e., air concentrations) alone in scientific studies are not directly comparable to the "level" element of the NAAQS because the standard considers the level in the context of its relation to the remaining elements. Failure to appreciate this has led to misunderstandings regarding NAAQS that would be health-protective. This can be seen with controlled human ozone exposure studies, which often involved small numbers of people exercising quasi-continuously for a long duration at an intensity not common in the general population (and unlikely achievable by most sensitive individuals), under worst-case exposure profiles. In addition, epidemiology studies have used different averaging times and have had methodological limitations that may have biased results. Such considerations can make it difficult to compare ozone levels and results across studies and to appropriately apply them in a NAAQS evaluation. Relating patterns and circumstances of exposure, and exposure measurements, to all elements of the NAAQS can be challenging, but if US EPA fully undertook this, it would be evident that available evidence does not indicate that proposed lower ozone standards would be more health protective than the current one.

  20. Are the elements of the proposed ozone National Ambient Air Quality Standards informed by the best available science?

    PubMed

    Goodman, Julie E; Sax, Sonja N; Lange, Sabine; Rhomberg, Lorenz R

    2015-06-01

    The United States Environmental Protection Agency (US EPA) issues National Ambient Air Quality Standards (NAAQS) for six criteria pollutants, including ozone. Each standard has four elements: an indicator, level, averaging time, and form. Ozone levels (i.e., air concentrations) alone in scientific studies are not directly comparable to the "level" element of the NAAQS because the standard considers the level in the context of its relation to the remaining elements. Failure to appreciate this has led to misunderstandings regarding NAAQS that would be health-protective. This can be seen with controlled human ozone exposure studies, which often involved small numbers of people exercising quasi-continuously for a long duration at an intensity not common in the general population (and unlikely achievable by most sensitive individuals), under worst-case exposure profiles. In addition, epidemiology studies have used different averaging times and have had methodological limitations that may have biased results. Such considerations can make it difficult to compare ozone levels and results across studies and to appropriately apply them in a NAAQS evaluation. Relating patterns and circumstances of exposure, and exposure measurements, to all elements of the NAAQS can be challenging, but if US EPA fully undertook this, it would be evident that available evidence does not indicate that proposed lower ozone standards would be more health protective than the current one. PMID:25857292

  1. Spatial and temporal patterns of ozone in the high elevation ecosystems of the Colorado Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Liptzin, D.; Helmig, D.

    2015-12-01

    Tropospheric ozone is regulated by the US EPA to protect human health and welfare. Because the precursors to ozone formation largely come from transportation and industrial activity, ozone has typically been thought of as an urban pollution problem. However, there is growing concern about increased ozone concentrations in rural areas. Surprisingly high ozone concentrations have been measured in the high elevation Rocky Mountain ecosystems in the Front Range of Colorado. The annual median ozone mixing ratios over the past decade at three high elevation monitoring stations ranged from 47 to 53 ppbv. The hourly ozone mixing ratio typically exceeds 100 ppbv at some point every year at these sites. The number of days where the ozone mixing ratio exceeded the current 8 hour US EPA National Ambient Air Quality Standard of 75 ppb has ranged from 0 to 25 since 1987 at the monitoring site in Rocky Mountain National Park. A comparison with lower elevation sites suggests that ozone mixing ratios generally increase with elevation. In addition, the diurnal and seasonal variability of ozone decreases with elevation. Along an elevational gradient from the plains to the tundra, the tundra site had the highest median values and the least variability of any site. The seasonal pattern at these high elevation sites is also distinct as the maximum mixing ratios occur in the spring in contrast to the summer maximum typically observed in urban areas. While there have been relatively small changes in concentration in the measured data record going back a few decades, modeling suggests that ozone mixing ratios have almost doubled over the last one hundred years in Colorado. A plethora of studies has shown that elevated ozone damages foliage, with sensitive species showing effect at levels exceeding 35-40 ppbv. Since ozone levels in these high elevation ecosystems are clearly above that, we believe that they have been and will continue to be severely affected by elevated ozone. It is not

  2. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... waiver of the ozone monitoring requirement would be handled under provisions of 40 CFR, part 58. Some... year unless the appropriate Regional Administrator has granted a waiver under the provisions of 40 CFR... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection...

  3. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... waiver of the ozone monitoring requirement would be handled under provisions of 40 CFR, part 58. Some... year unless the appropriate Regional Administrator has granted a waiver under the provisions of 40 CFR... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection...

  4. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... waiver of the ozone monitoring requirement would be handled under provisions of 40 CFR, part 58. Some... year unless the appropriate Regional Administrator has granted a waiver under the provisions of 40 CFR... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection...

  5. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... waiver of the ozone monitoring requirement would be handled under provisions of 40 CFR, part 58. Some... year unless the appropriate Regional Administrator has granted a waiver under the provisions of 40 CFR... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection...

  6. Unraveling the sources of ground level ozone in the Intermountain Western United States using Pb isotopes.

    PubMed

    Christensen, John N; Weiss-Penzias, Peter; Fine, Rebekka; McDade, Charles E; Trzepla, Krystyna; Brown, Shaun T; Gustin, Mae Sexauer

    2015-10-15

    Ozone as an atmospheric pollutant is largely produced by anthropogenic precursors and can significantly impact human and ecosystem health, and climate. The U.S. Environmental Protection Agency has recently proposed lowering the ozone standard from 75 ppbv (MDA8 = Maximum Daily 8-Hour Average) to between 65 and 70 ppbv. This will result in remote areas of the Intermountain West that includes many U.S. National Parks being out of compliance, despite a lack of significant local sources. We used Pb isotope fingerprinting and back-trajectory analysis to distinguish sources of imported ozone to Great Basin National Park in eastern Nevada. During discrete Chinese Pb events (> 1.1 ng/m(3) & > 80% Asian Pb) trans-Pacific transported ozone was 5 ± 5.5 ppbv above 19 year averages for those dates. In contrast, concentrations during regional transport from the Los Angeles and Las Vegas areas were 15 ± 2 ppbv above the long-term averages, and those characterized by high-altitude transport 3 days prior to sampling were 19 ± 4ppbv above. However, over the study period the contribution of trans-Pacific transported ozone increased at a rate of 0.8 ± 0.3 ppbv/year, suggesting that Asian inputs will exceed regional and high altitude sources by 2015-2020. All of these sources will impact regulatory compliance with a new ozone standard, given increasing global background.

  7. Unraveling the sources of ground level ozone in the Intermountain Western United States using Pb isotopes.

    PubMed

    Christensen, John N; Weiss-Penzias, Peter; Fine, Rebekka; McDade, Charles E; Trzepla, Krystyna; Brown, Shaun T; Gustin, Mae Sexauer

    2015-10-15

    Ozone as an atmospheric pollutant is largely produced by anthropogenic precursors and can significantly impact human and ecosystem health, and climate. The U.S. Environmental Protection Agency has recently proposed lowering the ozone standard from 75 ppbv (MDA8 = Maximum Daily 8-Hour Average) to between 65 and 70 ppbv. This will result in remote areas of the Intermountain West that includes many U.S. National Parks being out of compliance, despite a lack of significant local sources. We used Pb isotope fingerprinting and back-trajectory analysis to distinguish sources of imported ozone to Great Basin National Park in eastern Nevada. During discrete Chinese Pb events (> 1.1 ng/m(3) & > 80% Asian Pb) trans-Pacific transported ozone was 5 ± 5.5 ppbv above 19 year averages for those dates. In contrast, concentrations during regional transport from the Los Angeles and Las Vegas areas were 15 ± 2 ppbv above the long-term averages, and those characterized by high-altitude transport 3 days prior to sampling were 19 ± 4ppbv above. However, over the study period the contribution of trans-Pacific transported ozone increased at a rate of 0.8 ± 0.3 ppbv/year, suggesting that Asian inputs will exceed regional and high altitude sources by 2015-2020. All of these sources will impact regulatory compliance with a new ozone standard, given increasing global background. PMID:25934382

  8. Atmosphere-derived National Emissions of Ozone Depleting Substances and Substitutes for the United States

    NASA Astrophysics Data System (ADS)

    Hu, L.; Montzka, S. A.; Miller, J. B.; Andrews, A. E.; Miller, B. R.; Lehman, S.; Godwin, D.; Thoning, K. W.; Sweeney, C.; Chen, H.; Fischer, M. L.; Biraud, S.; Torn, M. S.; Mountain, M. E.; Nehrkorn, T.; Eluszkiewicz, J.; Saikawa, E.; Hall, B. D.; Elkins, J. W.; Tans, P. P.

    2014-12-01

    Chlorofluorocarbons (CFCs), halons, carbon tetrachloride (CCl4), and methyl chloroform (CH3CCl3) are strong ozone-depleting substances (ODSs). Their production and consumption have been controlled by the Montreal Protocol since 1989 in developed countries and 1999 in developing countries. Although global atmospheric burdens of some of these gases have been declining for the last decade, their emissions continue due to releases from their existing reservoirs. Hydrochlorofluorocarbons (HCFCs) are transitional substitutes for CFCs; because they also deplete stratospheric ozone, they are also controlled by the Montreal Protocol. Hydrofluorocarbons (HFCs) are replacements for CFCs and HCFCs. Due to incomplete understanding of the reservoir size and emission rates for ODSs and their substitutes, uncertainty of their national emissions from inventory-based "bottom-up" estimates is undetermined. In this study, we use our atmospheric observations from multiple surface sites and aircraft profiles across the continental US from 2008 to 2012, along with data from remote sites over the Pacific basin, to derive national emissions of ODSs and their substitutes using inverse modeling. The performance of our modeling framework and the sensitivity of derived emissions to prior fluxes and model-data mismatch errors were investigated by conducting a suite of synthetic-data experiments. Sensitivity of derived fluxes to boundary values and transport was explored in real-data inversions. Our preliminary results suggest that (1) US emissions of HCFC-22 and HCFC-142b are currently declining at faster rates than those reported by US EPA; (2) our emission estimate of HFC-134a, the most abundant HFCs in the atmosphere, is consistent with the estimate reported by US EPA, whereas our estimates for some currently minor HFCs (i.e. HFC-125 and HFC-143a) show no significant emission trends during 2008 - 2012, which is inconsistent with a 70 - 120 % increase over this period reported by US EPA; and

  9. Reports to the nation on our changing planet. Fall 1992, no. 2: Our ozone shield

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This document is the second in a series of publications on climate and global change intended for public education. They are a joint effort of the UCAR Office for Interdisciplinary Earth Studies and the NOAA Office of Global Programs. The various roles of atmospheric ozone are described and the mechanisms and consequences of stratospheric ozone depletion are discussed.

  10. 77 FR 30160 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: Nonattainment Area...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... areas for the 2008 ozone NAAQS until March 12, 2011, pending the NAAQS reconsideration.\\2\\ See 75 FR... apply to the areas that are designated as nonattainment for the 2008 ozone NAAQS. See 77 FR 8197. The..., and Sacramento Metro areas (May 5, 2010, 75 FR 24409) became effective June 4, 2010. The EPA is in...

  11. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... area has attaining data for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR... satisfies 40 CFR 58.20(f) which requires the State to provide for the establishment and maintenance of... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Ozone. 52.582...

  12. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... data for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends..., into the Georgia State Implementation Plan. This submittal satisfies 40 CFR 58.20(f) which requires the... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy: Ozone. 52.582...

  13. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... area has attaining data for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR... satisfies 40 CFR 58.20(f) which requires the State to provide for the establishment and maintenance of... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Ozone. 52.582...

  14. Ozone Air Quality Impacts of Shale Gas Development in South Texas Urban Areas

    NASA Astrophysics Data System (ADS)

    Chang, C.; Liao, K.

    2013-12-01

    Recent technological advances, mainly horizontal drilling and hydraulic fracturing, and continued drilling in shale, have increased domestic production of oil and gas in the United State (U.S.). However, shale gas developments could also affect the environment and human health, particularly in areas where oil and gas developments are new activities. This study is focused on the impacts of shale gas developing activities on summertime ozone air quality in South Texas urban areas since many of them are already ozone nonattainment areas. We use an integrated approach to investigate the ozone air quality impact of the shale gas development in South Texas urban areas. They are: (1) satellite measurement of precursors, (2) observations of ground-level ozone concentrations, and (3) air mass trajectory modeling. Nitrogen dioxide (NO2) is an important precursor to ozone formation, and summertime average tropospheric nitrogen dioxide (NO2) column densities measured by the National Aeronautics and Space Administration's Ozone Monitoring Instrument increased in the South Texas shale area (i.e., the Eagle Ford Shale area) in 2011 and 2012 as compared to 2008-2010. The U.S. Environmental Protection Agency's ground-level observations showed summertime average and peak ozone (i.e., the 4th highest daily maximum 8-hour average ozone) concentrations slightly increased from 2010 to 2012 in Austin and San Antonio. However, the frequencies of peak ozone concentrations above the 75ppb ozone standard have been significantly increasing since 2011 in Austin and San Antonio. It is expected to increase the possibilities of violating the ozone National Ambient Air Quality Standard (NAAQS) for South Texas urban areas in the future. The results of trajectory modeling showed air masses transported from the southeastern Texas could reach Austin and San Antonio and confirmed that emissions from the Eagle Ford Shale area could affect ozone air quality in South Texas urban areas in 2011 and 2012

  15. 40 CFR 52.2043 - Control strategy for maintenance plans: ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: ozone. 52.2043 Section 52.2043 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy for maintenance plans: ozone. (a) As of December 26, 2013, EPA approves the following... (VOCs) for the Lancaster 1997 8-Hour Ozone Maintenance Area submitted by the Secretary of...

  16. 40 CFR 52.2052 - Motor vehicle emissions budgets for Pennsylvania ozone areas.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Pennsylvania ozone areas. 52.2052 Section 52.2052 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...) Pennsylvania § 52.2052 Motor vehicle emissions budgets for Pennsylvania ozone areas. (a) As of December 26... nitrogen oxides (NOX) and volatile organic compounds (VOCs) for the Lancaster 1997 8-Hour Ozone...

  17. 40 CFR 52.1989 - Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Act section 169A and 40 CFR 51.308(e) regarding Best Available Retrofit Technology and the requirements of 40 CFR 51.308(d)(2) and (d)(4)(v) regarding the calculation of baseline and natural conditions for the Mt. Hood Wilderness Area, Mt. Jefferson Wilderness Area, Mt Washington Wilderness...

  18. Response of macaque bronchiolar epithelium to ambient concentrations of ozone.

    PubMed Central

    Harkema, J. R.; Plopper, C. G.; Hyde, D. M.; St George, J. A.; Wilson, D. W.; Dungworth, D. L.

    1993-01-01

    Recently, we reported that exposure to ambient concentrations of ozone, near the U.S. National Ambient Air Quality Standard (0.12 ppm), induced significant nasal epithelial lesions in a non-human primate, the bonnet monkey. The present study defines the effects of ambient concentrations of ozone on the surface epithelium lining respiratory bronchioles and on the underlying bronchiolar interstitium in these same monkeys. Bonnet monkeys were exposed to filtered air or to 0.15 or 0.30 ppm ozone 8 hours/day for 6 or 90 days. At the end of exposures, monkeys were anesthetized and killed by exsanguination. Microdissected bronchiolar airways of infusion-fixed lungs were evaluated morphometrically by light microscopy and quantitatively by scanning and transmission electron microscopy for ozone-induced epithelial changes. Hyperplasia of nonciliated, cuboidal epithelial cells and intraluminal accumulation of macrophages characterized ozone-induced lesions in respiratory bronchioles. There were no significant differences in epithelial thickness or cell numbers among ozone-exposed groups. Ozone-exposed epithelium was composed of 80% cuboidal and 20% squamous cells compared with 40% cuboidal and 60% squamous cells in filtered air controls. In addition, the arithmetic mean thickness of the surface epithelium, a measure of tissue mass per unit area of basal lamina, was significantly increased in all of the ozone-exposed groups. The number of cuboidal epithelial cells per surface area of basal lamina was increased above control values by 780% after 6 days exposure to 0.15 ppm, 777% after 90 days to 0.15 ppm, and 996% after 90 days exposure to 0.30 ppm. There was also a significant ozone-induced increase in the thickness of the bronchiolar interstitium that was due to an increase in both cellular and acellular components. These results demonstrate that exposure to low ambient concentrations of ozone, near the current. National Ambient Air Quality Standard, induces pulmonary lesions

  19. Evaluation of ozone injury on foliage of black cherry (Prunus serotina) and tall milkweed (Asclepias exaltata) in Great Smoky Mountains National Park.

    PubMed

    Chappelka, A; Renfro, J; Somers, G; Nash, B

    1997-01-01

    The incidence and severity of visible foliar ozone injury on black cherry (Prunus serotina) seedlings and saplings and tall milkweed (Asclepias exaltata) plants in Great Smoky Mountains National Park (GRSM) were determined by surveys along selected trails conducted during late summer 1992. The incidence (% injured plants) of ozone injury on black cherry was 47% and the percent injured leaves/injured plant and average leaf area injured were 43 and 6%, respectively. Maximum severity (avg. leaf area of the most severely injured leaf) was 12%. Black cherry seedlings and saplings exhibiting ozone injury were taller than non-injured plants. When insect feeding was present, it occurred 96% of the time on plants with ozone injury. Significantly more injury (p=0.007) on black cherry (% injured leaves/injured black cherry) occurred in the NW section of GRSM compared with the other Park sections. Regression analyses showed no relationships in ozone injury with respect to aspect, slope or elevation. Tall milkweed was evaluated twice during August for ozone injury. The incidence (% injured plants) of ozone injury was 74 and 79% for the first and second survey, respectively. The percentage of injured leaves per plant from the first to second survey was 63 to 79%, respectively. Tall milkweeds showing ozone injury were taller than the non-injured plants. The percentage of insect-damaged plants was 50% among plants without ozone injury and 60% among ozone-injured plants. Non-injured tall milkweed had fewer flowers and/or pods than the injured plants. Mean leaf area injured increased over time, and mean maximum leaf area injured increased from 8 to 11% during the same period. Regression analyses showed no differences in ozone injury regarding aspect, slope or elevation. Our findings indicate that ozone injury is widespread throughout the Park on sensitive vegetation. PMID:15093469

  20. Algorithm improvement and validation of National Institute for Environmental Studies ozone differential absorption lidar at the Tsukuba Network for Detection of Stratospheric Change complementary station.

    PubMed

    Park, Chan Bong; Nakane, Hideaki; Sugimoto, Nobuo; Matsui, Ichiro; Sasano, Yasuhiro; Fujinuma, Yasumi; Ikeuchi, Izumi; Kurokawa, Jun-Ichi; Furuhashi, Noritaka

    2006-05-20

    Recently, a data processing and retrieval algorithm (version 2) for ozone, aerosol, and temperature lidar measurements was developed for an ozone lidar system at the National Institute for Environmental Studies (NIES) in Tsukuba (36 degrees N,140 degrees E), Japan. A method for obtaining the aerosol boundary altitude and the aerosol extinction-to-backscatter ratio in the version 2 algorithm enables a more accurate determination of the vertical profiles of aerosols and a more accurate correction of the systematic errors caused by aerosols in the vertical profile of ozone. Improvements in signal processing are incorporated for the correction of systematic errors such as the signal-induced noise and the dead-time effect. The mean vertical ozone profiles of the NIES ozone lidar were compared with those of the Stratospheric Aerosol and Gas Experiment II (SAGE II); they agreed well within a 5% relative difference in the 20-40 km altitude range and within 10% up to 45 km. The long-term variations in the NIES ozone lidar also showed good coincidence with the ozonesonde and SAGE II at 20, 25, 30, and 35 km. The temperatures retrieved from the NIES ozone lidar and those given by the National Center for Environmental Prediction agreed within 7 K in the 35-50 km range.

  1. Ambient ozone effects on gas exchange and total non-structural carbohydrate levels in cutleaf coneflower (Rudbeckia laciniata L.) growing in Great Smoky Mountains National Park.

    PubMed

    Neufeld, Howard S; Peoples, Seth J; Davison, Alan W; Chappelka, Arthur H; Somers, Greg L; Thomley, Jill E; Booker, Fitzgerald L

    2012-01-01

    Ozone-sensitive and -tolerant individuals of cutleaf coneflower (Rudbeckia laciniata L.) were compared for their gas exchange characteristics and total non-structural carbohydrates at Purchase Knob, a high elevation site in Great Smoky Mountains National Park, USA. Photosynthesis and stomatal conductance decreased with increased foliar stipple. Sensitive plants had lower photosynthetic rates for all leaves, except the very youngest and oldest when compared to tolerant plants. Stomatal conductance decreased with increasing leaf age, but no ozone-sensitivity differences were found. Lower leaves had less starch than upper ones, while leaves on sensitive plants had less than those on tolerant plants. These results show that ambient levels of ozone in Great Smoky Mountains National Park can adversely affect gas exchange, water use efficiency and leaf starch content in sensitive coneflower plants. Persistence of sensitive genotypes in the Park may be due to physiological recovery in low ozone years. PMID:22035928

  2. 40 CFR 51.905 - How do areas transition from the 1-hour NAAQS to the 8-hour NAAQS and what are the anti...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Ambient Air Quality Standard § 51.905 How do areas transition from the 1-hour NAAQS to the 8-hour NAAQS...)(3)(iii) of this section. 40 CFR part 81, subpart C identifies the boundaries of areas and the area... obligations approved into the SIP pursuant to 40 CFR 51.121 and 51.122 may be modified by the State only...

  3. 40 CFR 51.905 - How do areas transition from the 1-hour NAAQS to the 8-hour NAAQS and what are the anti...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Ambient Air Quality Standard § 51.905 How do areas transition from the 1-hour NAAQS to the 8-hour NAAQS...)(3)(iii) of this section. 40 CFR part 81, subpart C identifies the boundaries of areas and the area... obligations approved into the SIP pursuant to 40 CFR 51.121 and 51.122 may be modified by the State only...

  4. First Global Observations of HCHO from the Suomi National Polar-orbiting Partnership Ozone Mapping and Profiler Suite

    NASA Astrophysics Data System (ADS)

    Li, C.; Joiner, J.; Krotkov, N. A.; Bhartia, P. K.; Dunlap, L.

    2014-12-01

    Global retrievals of formaldehyde (HCHO) from satellite UV instruments such as the Aura/Ozone Monitoring Instrument (OMI) and MetOp/Global Ozone Monitoring Experiment-2 (GOME-2) have provided important constraints on the emissions of biogenic isoprene. Here we present the first results of HCHO retrievals from the Suomi National Polar-orbiting Partnership (NPP) Ozone Mapping and Profiler Suite (OMPS). We apply an innovative principal component analysis (PCA) retrieval algorithm to extract a set of principal components (PCs) from OMPS-measured radiances between 325.0 and 356.5 nm over presumably clean oceanic regions. Since the background loading of HCHO due to methane oxidation is very small over these areas, the leading PCs (that explain the most variation in radiances) represent spectral features associated with various physical processes (e.g., ozone absorption, rotational Raman scattering) and measurement details (e.g., wavelength shift) other than those related to HCHO absorption. The vertical column density of HCHO is then derived by fitting the PCs and HCHO Jacobians calculated with a radiative transfer model to OMPS-measured radiance spectra. Our retrievals highlight the diverse nature of HCHO sources. Summertime maxima in HCHO detected over the eastern U.S. are likely due to biogenic emissions, while seasonal hot spots observed over West and Central Africa and Russia are mainly attributed to biomass burning emissions. Efforts have also been made to distinguish between anthropogenic and biogenic precursors of HCHO. Finally, the OMPS PCA HCHO retrievals are compared to OMI HCHO data produced with different Differential Optical Absorption Spectroscopy (DOAS) algorithms, in an effort to understand and reconcile the differences between various satellite HCHO datasets.

  5. Ozone Layer Observations

    NASA Technical Reports Server (NTRS)

    McPeters, Richard; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    The US National Aeronautics and Space Administration (NASA) has been monitoring the ozone layer from space using optical remote sensing techniques since 1970. With concern over catalytic destruction of ozone (mid-1970s) and the development of the Antarctic ozone hole (mid-1980s), long term ozone monitoring has become the primary focus of NASA's series of ozone measuring instruments. A series of TOMS (Total Ozone Mapping Spectrometer) and SBUV (Solar Backscatter Ultraviolet) instruments has produced a nearly continuous record of global ozone from 1979 to the present. These instruments infer ozone by measuring sunlight backscattered from the atmosphere in the ultraviolet through differential absorption. These measurements have documented a 15 Dobson Unit drop in global average ozone since 1980, and the declines in ozone in the antarctic each October have been far more dramatic. Instruments that measure the ozone vertical distribution, the SBUV and SAGE (Stratospheric Aerosol and Gas Experiment) instruments for example, show that the largest changes are occurring in the lower stratosphere and upper troposphere. The goal of ozone measurement in the next decades will be to document the predicted recovery of the ozone layer as CFC (chlorofluorocarbon) levels decline. This will require a continuation of global measurements of total column ozone on a global basis, but using data from successor instruments to TOMS. Hyperspectral instruments capable of measuring in the UV will be needed for this purpose. Establishing the relative roles of chemistry and dynamics will require instruments to measure ozone in the troposphere and in the stratosphere with good vertical resolution. Instruments that can measure other chemicals important to ozone formation and destruction will also be needed.

  6. 78 FR 34964 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... Federal Register on June 6, 2013, (78 FR 34178) and is available at: http://www.epa.gov/air/ozonepollution... on June 6, 2013, (78 FR 34178) and is available at http://www.epa.gov/air/ozonepollution/actions.html... for Ozone: State Implementation Plan Requirements AGENCY: Environmental Protection Agency...

  7. Ensemble Statistical Post-Processing of the National Air Quality Forecast Capability: Enhancing Ozone Forecasts in Baltimore, Maryland

    NASA Technical Reports Server (NTRS)

    Garner, Gregory G.; Thompson, Anne M.

    2013-01-01

    An ensemble statistical post-processor (ESP) is developed for the National Air Quality Forecast Capability (NAQFC) to address the unique challenges of forecasting surface ozone in Baltimore, MD. Air quality and meteorological data were collected from the eight monitors that constitute the Baltimore forecast region. These data were used to build the ESP using a moving-block bootstrap, regression tree models, and extreme-value theory. The ESP was evaluated using a 10-fold cross-validation to avoid evaluation with the same data used in the development process. Results indicate that the ESP is conditionally biased, likely due to slight overfitting while training the regression tree models. When viewed from the perspective of a decision-maker, the ESP provides a wealth of additional information previously not available through the NAQFC alone. The user is provided the freedom to tailor the forecast to the decision at hand by using decision-specific probability thresholds that define a forecast for an ozone exceedance. Taking advantage of the ESP, the user not only receives an increase in value over the NAQFC, but also receives value for An ensemble statistical post-processor (ESP) is developed for the National Air Quality Forecast Capability (NAQFC) to address the unique challenges of forecasting surface ozone in Baltimore, MD. Air quality and meteorological data were collected from the eight monitors that constitute the Baltimore forecast region. These data were used to build the ESP using a moving-block bootstrap, regression tree models, and extreme-value theory. The ESP was evaluated using a 10-fold cross-validation to avoid evaluation with the same data used in the development process. Results indicate that the ESP is conditionally biased, likely due to slight overfitting while training the regression tree models. When viewed from the perspective of a decision-maker, the ESP provides a wealth of additional information previously not available through the NAQFC alone

  8. CHEMICAL AND TOXICOLOGICAL EVALUATION OF CHLORINATED AND OZONATED-CHLORINATED DRINKING WATER: A COLLABORATION OF THE FOUR NATIONAL LABS OF THE U. S. EPA

    EPA Science Inventory

    CHEMICAL AND TOXICOLOGICAL EVALUATION OF CHLORINATED AND OZONATED-CHLORINATED DRINKING WATER: A COLLABORATION OF THE FOUR NATIONAL LABS OF THE U.S. EPA
    Susan D. Richardson1, Linda K. Teuschler2, Alfred D. Thruston, Jr.,1 Thomas Speth3, Richard J. Miltner3, Glenn Rice2, Kathle...

  9. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT... determining the expected number of annual exceedances relate to accounting for incomplete sampling. In general... waiver of the ozone monitoring requirement would be handled under provisions of 40 CFR, part 58....

  10. Ambient ozone effects on gas exchange and total non-structural carbohydrate levels in cutleaf coneflower (Rudbeckia laciniata L.) growing in Great Smoky Mountains National Park

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ozone-sensitive and -tolerant individuals of the perennial herbaceous cutleaf coneflower (Rudbeckia laciniata L.) were compared for their gas exchange characteristics and total non-structural carbohydrates in the Great Smoky Mountains National Park USA. Net photosynthesis decreased with increased f...

  11. Nonmethane hydrocarbons and ozone in three rural southeast United States national parks: A model sensitivity analysis and comparison to measurements

    NASA Astrophysics Data System (ADS)

    Kang, Daiwen; Aneja, Viney P.; Mathur, Rohit; Ray, John D.

    2003-10-01

    A detailed modeling analysis is conducted focusing on nonmethane hydrocarbons and ozone in three southeast United States national parks for a 15-day time period (14-29 July 1995) characterized by high O3 surface concentrations. The three national parks are Smoky Mountains National Park (GRSM), Mammoth Cave National Park (MACA), and Shenandoah National Park (SHEN), Big Meadows. A base emission scenario and eight variant predictions are analyzed, and predictions are compared with data observed at the three locations for the same time period. Model-predicted concentrations are higher than observed values for O3 (with a cutoff of 40 ppbv) by 3.0% at GRSM, 19.1% at MACA, and 9.0% at SHEN (mean normalized bias error). They are very similar to observations for overall mean ozone concentrations at GRSM and SHEN. They generally agree (the same order of magnitude) with observed values for lumped paraffin compounds but are an order of magnitude lower for other species (isoprene, ethene, surrogate olefin, surrogate toluene, and surrogate xylene). Model sensitivity analyses here indicate that each location differs in terms of volatile organic compound (VOC) capacity to produce O3, but a maximum VOC capacity point (MVCP) exists at all locations that changes the influence of VOCs on O3 from net production to production suppression. Analysis of individual model processes shows that more than 50% of daytime O3 concentrations at the high-elevation rural locations (GRSM and SHEN) are transported from other areas; local chemistry is the second largest O3 contributor. At the low-elevation location (MACA), about 80% of daytime O3 is produced by local chemistry and 20% is transported from other areas. Local emissions (67-95%) are predominantly responsible for VOCs at all locations, the rest coming from transport. Chemistry processes are responsible for about 50% removal of VOCs for all locations; less than 10% are lost to surface deposition and the rest are exported to other areas

  12. A Holistic Evaluation of the Houston, Texas Ozone Attainment Episode

    NASA Astrophysics Data System (ADS)

    Biton, L.; Vizuete, W.; Kim, B.; Jeffries, H. E.

    2006-12-01

    In early 2006, the Texas Commission on Environmental Quality (TCEQ) released a simulation episode to form the basis for its 8-Hour Ozone State Implementation Plan (SIP). The SIP details steps to be taken to bring the Houston-Galveston-Brazoria region into attainment of the National Ambient Air Quality Standard for ozone (O3). The modeling episode will have significant impacts on regulatory decision-making, thus affecting the regional economy and human health. At present model performance evaluations (MPEs) are based on guidelines set by the Environmental Protection Agency (EPA) that rely heavily on statistical measures. While the episode falls within the recommended range for these EPA statistical metrics, examining the level of agreement between model predictions and observations for O3 is not a sufficient method to assess model accuracy. We have discovered severe inaccuracies in the 8-Hour modeling episode with an evaluation methodology that recognizes that (1) the formation of tropospheric O3 system is non-linear with respect to its precursors and (2) is the result of a multitude of chemical, emission, and meteorological processes. This paper presents the results of this improved evaluation method using new tools and software developed at the University of North Carolina at Chapel Hill. These tools were designed specifically to compensate for inadequacies in the existing statistical methods currently used for MPE. These tools enable investigators to review O3 production and concentrations in the context of meteorological and chemical conditions, allowing more holistic analytical techniques, not captured by traditional statistical metrics. In our analysis all modeling results are compared with high-resolution data from multiple sources, including an extensive ground-monitoring network, automatic gas-chromatographs (auto-GCs), and aircraft. First in our investigation, as a measure of progress, the latest 8-Hour episode is compared to TCEQ"s previous 1-Hour O3 SIP

  13. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for each calendar day during the O3 monitoring season. The daily maximum 8-hour concentration for a...% of the days within the O3 monitoring season, on average, for the 3-year period, with a minimum data completeness requirement in any one year of at least 75% of the days within the O3 monitoring season....

  14. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for each calendar day during the O3 monitoring season. The daily maximum 8-hour concentration for a...% of the days within the O3 monitoring season, on average, for the 3-year period, with a minimum data completeness requirement in any one year of at least 75% of the days within the O3 monitoring season....

  15. Assessing the risk of foliar injury from ozone on vegetation in parks in the U.S. National Park Service's Vital Signs Network.

    PubMed

    Kohut, Robert

    2007-10-01

    The risk of ozone injury to plants was assessed in support of the National Park Service's Vital Signs Monitoring Network program. The assessment examined bioindicator species, evaluated levels of ozone exposure, and investigated soil moisture conditions during periods of exposure for a 5-year period in each park. The assessment assigned each park a risk rating of high, moderate, or low. For the 244 parks for which assessments were conducted, the risk of foliar injury was high in 65 parks, moderate in 46 parks, and low in 131 parks. Among the well-known parks with a high risk of ozone injury are Gettysburg, Valley Forge, Delaware Water Gap, Cape Cod, Fire Island, Antietam, Harpers Ferry, Manassas, Wolf Trap Farm Park, Mammoth Cave, Shiloh, Sleeping Bear Dunes, Great Smoky Mountains, Joshua Tree, Sequoia and Kings Canyon, and Yosemite.

  16. 40 CFR 52.1779 - Control strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-state Charlotte-Gastonia-Rockhill, North Carolina-South Carolina nonattainment area has attaining data for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends the requirements for this area to submit an attainment demonstration, associated reasonably available...

  17. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... satisfies 40 CFR 58.20(f) which requires the State to provide for the establishment and maintenance of... area has attaining data for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR... transportation control measures. (1) HOV Lane—This project referred to as AR 073B is the addition of HOV lanes...

  18. 75 FR 1566 - Public Hearings for Reconsideration of the 2008 National Ambient Air Quality Standards for Ozone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-12

    ... the following Web site: http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_fr.html for the addresses.../standards/ozone/s_o3_cr_fr.html . FOR FURTHER INFORMATION CONTACT: If you would like to speak at the public... proposal at http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_fr.html prior to the hearings....

  19. Lightning Nitrogen Oxides (LNOx) Vertical Profile Quantification and 10 Year Trend Analysis using Ozone Monitoring Instrument (OMI) Satellite Measurements, Air Quality Station (AQS) Surface Measurements, The National Lightning Detection Network (NLDN), and Simulated by Cloud Resolving Chemical Transport Model (REAM Cloud)

    NASA Astrophysics Data System (ADS)

    Smeltzer, C. D.; Wang, Y.; Koshak, W. J.

    2014-12-01

    Vertical profiles and emission lifetimes of lightning nitrogen oxides (LNOx) are derived using the Ozone Monitoring Instrument (OMI). Approximately 200 million flashes, over a 10 year climate period, from the United States National Lighting Detection Network (NLDN), are aggregated with OMI cloud top height to determine the vertical LNOx structure. LNOx lifetime is determined as function of LNOx signal in a 36 kilometer vertical column from the time of the last known flash to depletion of the LNOx signal. Environmental Protection Agency (EPA) Air Quality Station (AQS) surface data further support these results by demonstrating as much as a 200% increase in surface level NO2 during strong thunderstorm events and a lag as long as 5 to 8 hours from the lightning event to the peak surface event, indicating a evolutional process. Analysis of cloud resolving chemical transport model (REAM Cloud) demonstrates that C-shaped LNOx profiles, which agree with OMI vertical profile observations, evolve due to micro-scale convective meteorology given inverted C-shaped LNOx emission profiles as determined from lightning radio telemetry. It is shown, both in simulations and in observations, that the extent to which the LNOx vertical distribution is C-shaped and the lifetime of LNOx is proportional to the shear-strength of the thunderstorm. Micro-scale convective meteorology is not adequately parameterized in global scale and regional scale chemical transport models (CTM). Therefore, these larger scale CTMs ought to use a C-shape emissions profile to best reproduce observations until convective parameterizations are updated. These findings are used to simulate decadal LNOx and lightning ozone climatology over the Continental United States (CONUS) from 2004-2014.

  20. 75 FR 10420 - Approval and Promulgation of Implementation Plans: 1-Hour Ozone Extreme Area Plan for San Joaquin...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-08

    ....'' 57 FR 13498 (April 16, 1992). ARB used its mobile source emissions model EMFAC2002 to generate the on... of Proposed Actions On July 14, 2009 at 74 FR 33933, EPA proposed to approve in part and disapprove...-hour ozone standard). 69 FR 20550 (April 15, 2004). Although we established a new 8-hour ozone...

  1. Surface Ozone in Kiev

    NASA Astrophysics Data System (ADS)

    Shavrina, A. V.; Mikulskaya, I. A.; Kiforenko, S. I.; Blum, O. B.; Sheminova, V. A.; Veles, A. A.

    The study of total ozone over Kiev and its concentration changes with height in the troposphere has been made on the base of ground-based observations with the infrared Fourier-spectrometer in the Main Astronomical Observatory of National Academy of Sciences of Ukraine (MAO NASU) as part of ESA-NIVR-KNMI project no 2907 "OMI validation by ground based remote sensing: ozone columns and atmospheric profiles "(2005-2008) [1,2,4]. Ground-level ozone in Kiev for an episode of its high concentrations in August 2000 was also simulated with the model of urban air pollution UAM-V [5,6]. In 2008 the satellite data Aura-OMI on profiles of ozone in the atmosphere OMO3PR became available (http://disc.sci.gsfc.nasa.gov/ Aura/data-holdings/OMI/ omo3pr_v003.shtml). They include ozone content in the lower layer of the atmosphere, beginning from 2005, which can be used to evaluate the ground-level ozone in all cities of Ukraine. The comparison of the data of ozone air pollution in Kiev (ozone - the pollutant of the first class of danger) and medical statistics data of of respiratory system (RS) diseases of the city population was carried out with the package "Statistica". A regression analysis, prognostic regression modelling, and retrospective prognosis of the epidemiological situation with respect to RS pathologies in Kiev in 2000-2006 were performed.

  2. Overview of ozone human exposure and health risk analyses used in the U.S. EPA's review of the ozone air quality standard.

    SciTech Connect

    Whitfield, R. G.

    1999-03-04

    This paper presents an overview of the ozone human exposure and health risk analyses developed under sponsorship of the U.S. Environmental Protection Agency (EPA). These analyses are being used in the current review of the national ambient air quality standards (NAAQS) for ozone. The analyses consist of three principal steps: (1) estimating short-term ozone exposure for particular populations (exposure model); (2) estimating population response to exposures or concentrations (exposure-response or concentration-response models); and (3) integrating concentrations or exposure with concentration-response or exposure-response models to produce overall risk estimates (risk model). The exposure model, called the probabilistic NAAQS exposure model for ozone (pNEM/03), incorporates the following factors: hourly ambient ozone concentrations; spatial distribution of concentrations; ventilation state of individuals at time of exposure; and movement of people through various microenvironments (e.g., outdoors, indoors, inside a vehicle) of varying air quality. Exposure estimates are represented by probability distributions. Exposure-response relationships have been developed for several respiratory symptom and lung function health effects, based on the results of controlled human exposure studies. These relationships also are probabilistic and reflect uncertainties associated with sample size and variability of response among subjects. The analyses also provide estimates of excess hospital admissions in the New York City area based on results from an epidemiology study. Overall risk results for selected health endpoints and recently analyzed air quality scenarios associated with alternative 8-hour NAAQS and the current 1-hour standard for outdoor children are used to illustrate application of the methodology.

  3. SIMULATION OF OZONE EFFECTS ON EIGHT TREE SPECIES AT SHENANDOAH NATIONAL PARK

    EPA Science Inventory

    As part of an assessment of potential effects of air pollutants on the vegetation of Shenandoah National Park (SHEN), we simulated the growth of eight important tree species using TREGRO, a mechanistic model of individual tree growth. Published TREGRO parameters for black cherry...

  4. Ozone and Volatile Organic Compound Distributions in Rocky Mountain National Park During FRAPPÉ: Impacts of Oil and Natural Gas Operations and Urban Emissions on Park Air Quality

    NASA Astrophysics Data System (ADS)

    Sive, B. C.; Zhou, Y.; Evanoski-Cole, A.; Benedict, K. B.; Prenni, A. J.; Thompson, T. M.; Day, D.; Fischer, E. V.; Callahan, S. L.; Cheatham, J.; Schichtel, B. A.; Apel, E. C.; Hornbrook, R. S.; Sullivan, A.; Vimont, J.; Collett, J. L., Jr.

    2015-12-01

    The Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ) occurred during July and August 2014. This study focused on characterizing and understanding summertime air quality in the Northern Front Range Metropolitan Area (NFRMA), with an emphasis on ozone and its precursors. Exceedances of the National Ambient Air Quality Standard (NAAQS) for ozone occur regularly in the NFRMA during the summertime and impact air quality in Rocky Mountain National Park (ROMO). As part of FRAPPÉ, the National Park Service supplemented its long-term monitoring at its Longs Peak site (~9000 ft.) with enhanced trace gas and aerosol measurements; ozone and meteorological measurements were also deployed at a high altitude site off of Trail Ridge Road (~11,600 ft.). At Longs Peak, a suite of volatile organic compounds (VOCs), including nonmethane hydrocarbons, halocarbons, alkyl nitrates and oxygenated VOCs (OVOCs), were measured using a cryogen-free gas chromatographic system and a proton transfer reaction-mass spectrometer. Additionally, whole air samples were collected along a route from Fort Collins, CO up to Trail Ridge Road several times per week. The transect samples were typically collected during upslope events and aircraft deployment days to characterize air mass composition and to aid in linking the surface and airborne measurements. Ozone distributions from Trail Ridge Road and Longs Peak generally tracked well temporally, with the highest ozone levels measured at the high elevation site; maximum hourly values during FRAPPÉ were 82 ppb and 79 ppb, respectively. A mixed signature containing both urban and oil and gas emissions was regularly observed in air masses encountered in the park, with elevated ozone and VOC levels measured during upslope events. However, the highest levels of alkanes measured at Longs Peak were associated with oil and gas operations, based on the isopentane to n-pentane ratio. Transect samples and aircraft data collected during an upslope

  5. Alteration in carboxyhemoglobin concentrations during exposure to 9 ppm carbon monoxide for 8 hours at sea level and 2134 m altitude in a hypobaric chamber

    SciTech Connect

    Horvath, S.M.; Bedi, J.F. )

    1989-10-01

    Seventeen non-smoking young men served as subjects to determine the alteration in carboxyhemoglobin (COHb) concentrations during exposure to 0 or 9 ppm carbon monoxide for 8 hours (CO) at sea level or an altitude of 2134 meters (7000 feet) in a hypobaric chamber. Nine subjects rested during the exposure and 8 exercised for 10 minutes of each exposure hour at a mean ventilation of 25 L (BTPS). All subjects performed a maximal aerobic capacity test at the completion of their respective exposures. Carboxyhemoglobin concentrations fell in all subjects during their exposures to 0 ppm CO at sea level or 2134 m. During the 8-h exposures to 9 ppm CO, COHb rose linearly from approximately 0.2 percent to 0.7 percent. No significant differences in uptake were found whether the subjects were resting or intermittently exercising during their 8-h exposures. COHb levels attained were similar at both sea level and 2134 m. Maximal aerobic capacity was reduced approximately 7-10 percent consequent to altitude exposure during 0 ppm CO exposures. These values were not altered following exposure for 8 h to 9 ppm CO in either the resting or exercising subjects.

  6. Evaluating 2012 Ozone Impacts of Natural Gas Development in the Haynesville Shale with an Updated Emission Inventory

    NASA Astrophysics Data System (ADS)

    Kemball-Cook, S. R.; Bar-Ilan, A.; Yarwood, G.

    2013-12-01

    The Haynesville Shale, located approximately 10,000-13,000 feet beneath Northeast Texas and Northwest Louisiana contains very large recoverable reserves of natural gas. Development of the Haynesville began in 2008, and since then, more than 3,000 wells have been drilled. The development of natural gas resources in the Haynesville is economically important, but also generates emissions of ozone precursors in a region with several ozone monitors that are close to or exceeding the 2008 National Ambient Air Quality Standard. During 2009, we developed an emission inventory of ozone precursors for projected future Haynesville Shale development from 2009 through 2020. Photochemical modeling with the 2012 emission inventory showed significant ozone impacts within Northeast Texas and Northwest Louisiana as a result of Haynesville emissions, with projected 8-hour ozone design value increases up to 5 ppb at area monitors. The original emission inventory was assembled during spring 2009, early in the development of the Haynesville when available data were limited. Since then, development in the Haynesville has continued, and additional data are now available and were used to refine the development projections and emission inventory through the year 2020. The updated 2012 emission inventory is now based on actual data rather than projections made in 2009. The number of drilling rigs operating in 2012 was lower than projected, but the well count was higher due intensive drilling activity in 2010-2011 that exceeded projections. The updated emission inventory draws on more Haynesville-specific data than the previous inventory. Energy producers currently active in the Haynesville were surveyed and provided information that included well drilling times, equipment used for well construction, production equipment present at typical Haynesville wells, and produced gas composition analyses. Producers provided information on the amount of truck traffic associated with transport of

  7. Persistence of peak flow decrement in children following ozone exposures exceeding the national ambient air quality standard

    SciTech Connect

    Lioy, P.J.; Vollmuth, T.A.; Lippmann, M.

    1985-10-01

    A linear regression was calculated between the peak one-hour ozone concentration for a given day and forced vital capacity (FVC), forced expiratory volume in one second (FEV), and peak expiratory flow rate (PEFR) as determined the same day from spirograms for each of the 39 children tested on six or more days. All mean slopes were negative, except for FVC in boys, indicating a general tendency for decreased function with increasing ozone concentration. In another analysis, a summary weighted correlation coefficient between peak ozone level and each pulmonary function parameter was calculated for each of 49 children seen on four or more days. As in the regression analysis, decrements in PEFR were significantly correlated with the ozone exposure. Analysis of residuals from the regression lines provide evidence for responses of greater potential significance to the future health of the children. They indicate a different kind of response, i.e., a persistent decrement in function lasting for as much as a week after the end of a smog period of about four days' duration. The persistent effects associated with ozone could have been due to acidic sulfates as well as, or in addition to, ozone. 10 references, 2 figures, 2 tables.

  8. Climate Suite Study for the National Polar-Orbiting Operational Environmental Satellite System Internal Concepts Study. Part A; Ozone Sensors

    NASA Technical Reports Server (NTRS)

    Lucke, R. L.; Planet, Walter G.; Hudson, R. D.

    1995-01-01

    Our recommendations to NPOESS for the sensors it should adopt to meet threshold requirements for global monitoring of ozone and, to some extent, of aerosols and of atmospheric temperature, pressure, and water vapor content are summarized in this report. The degree to which these sensors fulfill other NPOESS requirements than ozone is also summarized. The number of sensors that should be in the constellation is discussed in terms of desired reliability, continuity of coverage, and the ability to cross-calibrate successive sensors. Our recommendations for specific ozone measurement requirements, IORD item 4.1.6.2.28, are given. We make the case that the monitoring of three minor constituents in the upper atmosphere (N20, ClO or ClONO2, and HNO3) should be added to the list of NPOESS requirements because of their importance to long-term ozone studies and the small additional cost required (ozone sensors are already designed to measure them). Specific measurement requirements, which should be regarded as supplementary to the ozone requirement, are given here. The necessity of using two types of sensors, nadir-viewers and limb-scanners, for atmospheric studies is discussed.

  9. Ozone Layer Educator's Guide.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

    This guide has been developed through a collaborative effort involving the U.S. Environmental Protection Agency (EPA), the National Oceanic and Atmospheric Administration (NOAA), and the National Aeronautics and Space Administration (NASA). It is part of an ongoing commitment to ensure that the results of scientific research on ozone depletion are…

  10. Stratospheric ozone depletion.

    PubMed

    Rowland, F Sherwood

    2006-05-29

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290-320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime-the 'Antarctic ozone hole'. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules.

  11. Stratospheric ozone depletion

    PubMed Central

    Rowland, F. Sherwood

    2006-01-01

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290–320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime—the ‘Antarctic ozone hole’. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  12. Stratospheric ozone depletion.

    PubMed

    Rowland, F Sherwood

    2006-05-29

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290-320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime-the 'Antarctic ozone hole'. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  13. Balloonborne ozone and aerosol measurements in the antarctic ozone hole

    SciTech Connect

    Hofmann, D.J.; Harder, J.W.; Rolf, S.R.; Rosen, J.M. )

    1987-01-01

    The National Ozone Expedition (NOZE) was mounted in 1986 using winter fly-in flights to McMurdo Station in August, which is approximately the time the ozone reduction begins. The University of Wyoming Atmospheric Physics group participated in this expedition through balloonborne measurements of the vertical distribution of ozone and aerosol particles. Between 24 August and 6 November, 33 ozone soundings, 6 aerosol sounding, and 3 condensation nuclei soundings were conducted using polyethylene balloons which were able to penetrate the cold (< {minus}80C) antarctic stratosphere. The authors summarize these results here.

  14. The Effects of Gaseous Ozone and Nitric Acid Deposition on two Crustose Lichen Species From Joshua Tree National Park

    NASA Astrophysics Data System (ADS)

    Hessom, Elizabeth Curie

    Lichens are dependent on atmospheric deposition for much of their water and nutrients, and due to their sensitivity to pollutants, are commonly used as bioindicators for air quality. While studies have focused on epiphytic (tree dwelling) lichens as bioindicators, virtually nothing is known about crustose (rock dwelling) lichens. The atmospheric pollutants ozone (O 3) and nitric acid (HNO3) are two major pollutants found within the Los Angeles Basin. While recent O3 research suggests it does not significantly affect lichen growth, HNO3 appears to be phytotoxic to some lichens. As both of these pollutants are deposited downwind from the L.A. basin into Joshua Tree National Park (JOTR), lichen species located in the park may provide a sensitive indicator of pollution effects. This research studied two lichen species of particular interest from Joshua Tree National Park, Lobothallia praeradiosa (Nyl.) Hafellner, and Acarospora socialis H. Magn., both of which are crustose species with unknown sensitivities to O3, as well as hypothesized and unknown sensitivities to nitrogen compounds, respectively. Little research exists for either species, possibly because of the difficulty in working with crustose lichens. This research attempted to expand the background knowledge of these species by exposing them to varying levels of O3 and HNO3, to ascertain their physiological responses. Physiological measures of chlorophyll fluorescence, dark respiration, microscopic imaging, and lichen washes (as a proxy for membrane leakage), were measured throughout the exposure period. Results indicated that both species had similar sensitivities to O3 and HNO3. Both species registered physical damage during the O3 fumigation, as well as a decrease in respiration. Neither species showed major physical damage to HNO3, but both manifested a decrease in chlorophyll fluorescence, suggesting damage to the photosynthetic systems of the algae symbiont. These results suggest that both of these

  15. CFCS and the ozone layer.

    PubMed

    Hayman, G D

    1997-05-01

    Ozone is an important constituent of the atmosphere. Ozone forms a distinct layer in the lower stratosphere known as the ozone layer. The ozone layer acts as a fragile shield because it protects man and other life forms from exposure to harmful short-wavelength ultraviolet (UV) radiation. The agents, particularly chemical, which affect the amount of ozone present in the atmosphere have been a source of concern for more than 20 years. This has been reinforced by the dramatic decline of stratospheric ozone levels first measured in Antarctica and now apparent worldwide. The combination of routine measurements of ozone depletion, careful laboratory studies and mathematical modelling of ozone in the atmosphere, has demonstrated that the reactive fragments produced when chlorofluorocarbons (CFCs), halons and other halogenated compounds break down in the stratosphere are responsible for the ozone loss. As CFCs have widespread and sometimes apparently essential uses in modern society, there has been an intense effort to develop safe, effective replacements which have a negligible or much smaller impact on the environment. The Montreal Protocol, signed by over 140 nations, has been implemented to control and phase out the chemical compounds responsible for ozone loss.

  16. Postlaunch Performance of the Suomi National Polar-Orbiting Partnership Ozone Mapping and Profiler Suite (OMPS) Nadir Sensors

    NASA Technical Reports Server (NTRS)

    Seftor, C. J.; Jaross, G.; Kowitt, M.; Haken, M.; Li, J.; Flynn, L. E.

    2014-01-01

    The prelaunch specifications for nadir sensors of the Ozone Mapping and Profiler Suite (OMPS) were designed to ensure that measurements from them could be used to retrieve total column ozone and nadir ozone profile information both for operational use and for use in long-term ozone data records. In this paper, we will show results from our extensive analysis of the performance of the nadir mapper (NM) and nadir profiler (NP) sensors during the first year and a half of OMPS nadir operations. In most cases, we determined that both sensors meet or exceed their prelaunch specifications. Normalized radiance (radiance divided by irradiance) measurements have been determined to be well within their 2% specification for both sensors. In the case of stray light, the NM sensor is within its 2% specification for all but the shortest wavelengths, while the NP sensor is within its 2% specification for all but the longest wavelengths. Artifacts that negatively impacted the sensor calibration due to diffuser features were reduced to less than 1% through changes made in the solar calibration sequence. Preliminary analysis of the disagreement between measurements made by the NM and NP sensors in the region where their wavelengths overlap indicates that it is due to shifts in the shared dichroic filter after launch and that it can be corrected. In general, our analysis indicates that both the NM and NP sensors are performing well, that they are stable, and that any deviations from nominal performance can be well characterized and corrected.

  17. 77 FR 34221 - Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards for Several...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-11

    ... Federal Regulations D.C. District of Columbia EPA Environmental Protection Agency FR Federal Register... country for the 2008 ozone NAAQS (77 FR 30088; May 21, 2012). At that time, the EPA did not designate 12... protective level. \\1\\ See 73 FR 16436; March 27, 2008. For a detailed explanation of the calculation of the...

  18. Postlaunch performance of the Suomi National Polar-orbiting Partnership Ozone Mapping and Profiler Suite (OMPS) nadir sensors

    NASA Astrophysics Data System (ADS)

    Seftor, C. J.; Jaross, G.; Kowitt, M.; Haken, M.; Li, J.; Flynn, L. E.

    2014-04-01

    The prelaunch specifications for nadir sensors of the Ozone Mapping and Profiler Suite (OMPS) were designed to ensure that measurements from them could be used to retrieve total column ozone and nadir ozone profile information both for operational use and for use in long-term ozone data records. In this paper, we will show results from our extensive analysis of the performance of the nadir mapper (NM) and nadir profiler (NP) sensors during the first year and a half of OMPS nadir operations. In most cases, we determined that both sensors meet or exceed their prelaunch specifications. Normalized radiance (radiance divided by irradiance) measurements have been determined to be well within their 2% specification for both sensors. In the case of stray light, the NM sensor is within its 2% specification for all but the shortest wavelengths, while the NP sensor is within its 2% specification for all but the longest wavelengths. Artifacts that negatively impacted the sensor calibration due to diffuser features were reduced to less than 1% through changes made in the solar calibration sequence. Preliminary analysis of the disagreement between measurements made by the NM and NP sensors in the region where their wavelengths overlap indicates that it is due to shifts in the shared dichroic filter after launch and that it can be corrected. In general, our analysis indicates that both the NM and NP sensors are performing well, that they are stable, and that any deviations from nominal performance can be well characterized and corrected.

  19. The ozone backlash

    SciTech Connect

    Taubes, G.

    1993-06-11

    While evidence for the role of chlorofluorocarbons in ozone depletion grows stronger, researchers have recently been subjected to vocal public criticism of their theories-and their motives. Their understanding of the mechanisms of ozone destruction-especially the annual ozone hole that appears in the Antarctic-has grown stronger, yet everywhere they go these days, they seem to be confronted by critics attacking their theories as baseless. For instance, Rush Limbaugh, the conservative political talk-show host and now-best-selling author of The Way Things Ought to Be, regularly insists that the theory of ozone depletion by CFCs is a hoax: bladerdash and poppycock. Zoologist Dixy Lee Ray, former governor of the state of Washington and former head of the Atomic Energy Commission, makes the same argument in her book, Trashing the Planet. The Wall Street Journal and National Review have run commentaries by S. Fred Singer, a former chief scientists for the Department of Transportation, purporting to shoot holes in the theory of ozone depletion. Even the June issue of Omni, a magazine with a circulation of more than 1 million that publishes a mixture of science and science fiction, printed a feature article claiming to expose ozone research as a politically motivated scam.

  20. 40 CFR 52.977 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy and regulations: Ozone... and regulations: Ozone. Determination of Attainment. Effective March 12, 2010 EPA has determined the Baton Rouge 1-hour ozone nonattainment area has attained the 1-hour ozone National Ambient Air...

  1. 78 FR 9596 - Approval and Promulgation of Implementation Plans; New Jersey and New York Ozone Attainment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-11

    ... attainment of the 1997 8-hour ozone NAAQS during this monitoring period. See 77 FR 36163, 77 FR 47533, 77 FR 17341, and 74 FR 63993. EPA is aware that preliminary ambient air quality monitoring data for 2012 may... moderate nonattainment areas. On December 11, 2012 (77 FR 73570), EPA published a notice of...

  2. 78 FR 21302 - Approval and Promulgation of Implementation Plans; New York State Ozone Implementation Plan Revision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ... outdoors, and individuals with a pre-existing respiratory disease, such as asthma. On April 30, 2004 (69 FR... a requirement to submit a demonstration of attainment. EPA notes that on December 7, 2009 (74 FR..., 2008 (73 FR 15672) EPA determined that Jefferson County attained the 8-hour ozone standard. On June...

  3. 76 FR 77178 - Approval and Promulgation of Implementation Plans; New York State Ozone Implementation Plan Revision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-12

    ... individuals with a pre-existing respiratory disease, such as asthma. On April 30, 2004 (69 FR 23858), EPA... Poughkeepsie nonattainment area is composed of Dutchess, Orange and Putnam counties. On December 7, 2009 (74 FR 63993), EPA determined that the Poughkeepsie area attained the 8-hour ozone standard and on March...

  4. 77 FR 26950 - Designation of Areas for Air Quality Planning Purposes; California; Western Mojave Desert Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-08

    ...'' nonattainment for the 1997 8-hour ozone NAAQS.\\1\\ See 69 FR 23858, at 23884 (April 30, 2004) and 40 CFR 81.305... FR 29073, May 20, 2008), and reclassified the Sacramento Metro area from ``Serious'' to ``Severe-15'' nonattainment effective June 4, 2010 (75 FR 24409, May 5, 2010). \\3\\ CARB subsequently submitted a SIP...

  5. 78 FR 7672 - Approval and Promulgation of Implementation Plans; Texas; Beaumont/Port Arthur Ozone Maintenance...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... Vehicle Emissions Simulator (MOVES) 2010a emissions model. The BPA 1997 8-hour ozone maintenance area... index, some information is not publicly available, e.g., Confidential Business Information or other... at the Air Planning Section (6PD-L), Environmental Protection Agency, 1445 Ross Avenue, Suite...

  6. Improved Space-Time Forecasting of next Day Ozone Concentrations in the Eastern U.S.

    EPA Science Inventory

    There is an urgent need to provide accurate air quality information and forecasts to the general public and environmental health decision-makers. This paper develops a hierarchical space-time model for daily 8-hour maximum ozone concentration (O3) data covering much of the easter...

  7. 76 FR 48207 - Federal Implementation Plans: Interstate Transport of Fine Particulate Matter and Ozone and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-08

    ... FIP Federal Implementation Plan FR Federal Register EPA U.S. Environmental Protection Agency GHG... proposed revisions to the 8-hour ozone NAAQS that the Agency had issued March 12, 2008 (75 FR 2938); the... the District of Columbia Circuit (``Court'') in 2008. CAIR, promulgated May 12, 2005 (70 FR...

  8. New ozone standard in the U.S.A. applied to Mexico City metropolitan air quality

    SciTech Connect

    Bravo A, H. Sosa E, R.; Sanchez A, P.; Jaimes P, M.

    1998-12-31

    The air quality of the Mexico City Metropolitan Zone (MCMZ) is recognized as one of the worst air pollution problems in the world. At the present, ozone is the most critical atmospheric pollutant in the area. According to the air quality data of the monitoring station at the University of Mexico, the ozone problem started in 1986. Mexican Ozone Air Quality Standard (MOAQS) specifies that a concentration of 0.11 ppm must not be exceeded more than one hour a day, one day a year in the term of three years. The Official Air Quality Data (RAMA) from 19 monitoring stations in the MCMZ coincides with the University station`s data, presenting the same atmospheric pollution problem. In the most critical sites the MOAQS is exceeded more than 1,300 hours in a year. Now, the Environmental Protection Agency of the United States (EPA) is working to establish the new ozone standard. EPA is setting the standard at 0.08 ppm on an average of 8 hours, considering the 3 year average of the annual 4th highest daily maximum 8 hour ozone concentration. The purpose of this paper is to present the tendency and comparison between two standards (1 hour and 8 hours) of the ozone concentrations in the MCMZ, since 1986 to 1996. Although Mexico does not yet have the 8 hour standard for ozone, it is very important to analyze the existing air quality data with this new standard. In this way the aim is to protect the health of more than 20 million inhabitants in the MCMZ.

  9. Smoke in the City: How Often and Where Does Smoke Impact Summertime Ozone in the United States?

    NASA Astrophysics Data System (ADS)

    Brey, S. J.; Fischer, E. V.

    2015-12-01

    The mechanisms and magnitude of the contribution of fires to ozone (O3) production is poorly understood. In this work we investigate the influence of fire on O3 abundances over the contiguous United States. Using co-located observations of particulate matter (PM2.5) and the National Weather Service Hazard Mapping System smoke data, we identify summertime days between 2005 and 2014 that Environmental Protection Agency (EPA) Air Quality System (AQS) O3 monitors are influenced by smoke. We then compare O3 mixing ratio distributions for smoke-free and smoke-impacted days for each O3 monitor. We observe that the mean O3 abundance measured on smoke-impacted days is higher than on smoke-free days. The magnitude of the effect varies by location with a range of 0 to 37 parts per billion by volume (ppbv). We find that smoke is present on a non-negligible proportion of days when the 8-hour average O3 mixing ratio exceeds the EPA limit of 75 ppbv in regions and locations with significant O3 issues, including the Northeast urban corridor, Dallas, Houston, Atlanta, Birmingham, and Kansas City. Most U.S. cities maintain a similar proportion of smoke-impacted exceedence days when they are held against a more stringent limit of 65 ppbv for an 8-hour average. We show that smoke-impacted O3 mixing ratios are most elevated in U.S. cities with the highest emissions of nitrogen oxides (NOX).

  10. 40 CFR 51.905 - How do areas transition from the 1-hour NAAQS to the 1997 8-hour NAAQS and what are the anti...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... National Ambient Air Quality Standard § 51.905 How do areas transition from the 1-hour NAAQS to the 1997 8... NAAQS maintenance area, the State may request that obligations under the applicable requirements of § 51.... Control obligations approved into the SIP pursuant to 40 CFR 51.121 and 51.122 may be modified by...

  11. 40 CFR 51.905 - How do areas transition from the 1-hour NAAQS to the 1997 8-hour NAAQS and what are the anti...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... National Ambient Air Quality Standard § 51.905 How do areas transition from the 1-hour NAAQS to the 1997 8... requirement to submit a maintenance plan for purposes of paragraph (a)(3)(iii) of this section. 40 CFR part 81.... Control obligations approved into the SIP pursuant to 40 CFR 51.121 and 51.122 may be modified by...

  12. Ozone decomposition

    PubMed Central

    Batakliev, Todor; Georgiev, Vladimir; Anachkov, Metody; Rakovsky, Slavcho

    2014-01-01

    Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers). Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates. PMID:26109880

  13. Ozone decomposition.

    PubMed

    Batakliev, Todor; Georgiev, Vladimir; Anachkov, Metody; Rakovsky, Slavcho; Zaikov, Gennadi E

    2014-06-01

    Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers). Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates. PMID:26109880

  14. Polar ozone

    NASA Technical Reports Server (NTRS)

    Solomon, S.; Grose, W. L.; Jones, R. L.; Mccormick, M. P.; Molina, Mario J.; Oneill, A.; Poole, L. R.; Shine, K. P.; Plumb, R. A.; Pope, V.

    1990-01-01

    The observation and interpretation of a large, unexpected ozone depletion over Antarctica has changed the international scientific view of stratospheric chemistry. The observations which show the veracity, seasonal nature, and vertical structure of the Antarctic ozone hole are presented. Evidence for Arctic and midlatitude ozone loss is also discussed. The chemical theory for Antarctic ozone depletion centers around the occurrence of polar stratospheric clouds (PSCs) in Antarctic winter and spring; the climatology and radiative properties of these clouds are presented. Lab studies of the physical properties of PSCs and the chemical processes that subsequently influence ozone depletion are discussed. Observations and interpretation of the chemical composition of the Antarctic stratosphere are described. It is shown that the observed, greatly enhanced abundances of chlorine monoxide in the lower stratosphere are sufficient to explain much if not all of the ozone decrease. The dynamic meteorology of both polar regions is given, interannual and interhemispheric variations in dynamical processes are outlined, and their likely roles in ozone loss are discussed.

  15. Ozone decomposition.

    PubMed

    Batakliev, Todor; Georgiev, Vladimir; Anachkov, Metody; Rakovsky, Slavcho; Zaikov, Gennadi E

    2014-06-01

    Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers). Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates.

  16. Ambient levels and temporal trends of VOCs, including carbonyl compounds, and ozone at Cabañeros National Park border, Spain

    NASA Astrophysics Data System (ADS)

    Villanueva, Florentina; Tapia, Araceli; Notario, Alberto; Albaladejo, José; Martínez, Ernesto

    2014-03-01

    Concentration levels of 15 carbonyls, 17 VOCs and ozone were studied at Cabañeros National Park border, Spain, in an area mainly constituted by holm oaks (Quercus ilex) and cork oaks (Quercus suber), along with scrubland formations such as rock-rose and heather. The compounds were collected by means of diffusive samplers from August-November 2010 and February-August 2011. Carbonyl compounds, VOCs and O3 were analysed by HPLC with diode array UV-Vis detector, GC-FID and by UV-visible spectrophotometry, respectively. The most abundant carbonyls were hexanal, acetone-acrolein, formaldehyde and acetaldehyde. Seasonal variation was apparent with maximum values observed in summer months. Total carbonyl concentrations ranged from 2.8 to 19.7 μg m-3. Most VOCs studied (using chemically desorbable cartridges) were either not detected or were below their detection limits, however, a parallel sampling using thermally desorbable cartridges, from May 22 to June 19, revealed the presence of much more VOCs, identified using GC-MS. O3 concentration ranged from 27.2 to 90.5 μg m-3, reaching the maximum monthly mean concentration in March (84.4 μg m-3). The analysis of back trajectories indicates the transport of polluted air masses from remote areas, mainly from the Mediterranean basin that should contribute to the high levels of ozone observed.

  17. Ozone variability

    NASA Astrophysics Data System (ADS)

    Duetsch, H. U.

    1983-09-01

    The annual and long-term variations in the atmospheric ozone layer were examined on the basis of 55 yr of data taken at Aroya, Switzerland and 25 yr of data gathered by the global ozone network. Attention was given to annual and biennial variations, which showed that the midlatitude peak concentration was affected by a quasi-biennial variation of the tropical stratospheric circulation. Smaller scale circulation patterns were dominant in the lower stratosphere, although an observed negative trend of the total ozone was equally distributed between the troposphere and 24 km altitude. The global ozone increase detected in the 1960s was possible due to general circulation alterations, but may also have been influenced by injection of NO(x) into the atmosphere during atomic bomb testing.

  18. Ozone, Tropospheric

    NASA Technical Reports Server (NTRS)

    Fishman, Jack

    1995-01-01

    In the early part of the 20th century, ground-based and balloon-borne measurements discovered that most of atmosphere's ozone is located in the stratosphere with highest concentrations located between 15 and 30 km (9,3 and 18.6 miles). For a long time, it was believed that tropospheric ozone originated from the stratosphere and that most of it was destroyed by contact with the earth's surface. Ozone, O3, was known to be produced by the photo-dissociation of molecular oxygen, O2, a process that can only occur at wavelengths shorter than 242 nm. Because such short-wave-length radiation is present only in the stratosphere, no tropospheric ozone production is possible by this mechanism. In the 1940s, however, it became obvious that production of ozone was also taking place in the troposphere. The overall reaction mechanism was eventually identified by Arie Haagen-Smit of the California Institute of Technology, in highly polluted southern California. The copious emissions from the numerous cars driven there as a result of the mass migration to Los Angeles after World War 2 created the new unpleasant phenomenon of photochemical smog, the primary component of which is ozone. These high levels of ozone were injuring vegetable crops, causing women's nylons to run, and generating increasing respiratory and eye-irritation problems for the populace. Our knowledge of tropospheric ozone increased dramatically in the early 1950s as monitoring stations and search centers were established throughout southern California to see what could be done to combat this threat to human health and the environment.

  19. Ozone exposure-response curves for tree species in Great Smoky Mountains National Park: A re-evaluation of how potential impacts may have changed over the past 25 years

    EPA Science Inventory

    Seedlings of tree species native to Great Smoky Mountains National Park were exposed to ozone in open-top chambers for one or two growing seasons. Species used were red maple (Acer rubrum), chestnut oak (Quercus prinus), black locust (Robinia pseudoacadia), winged sumac (Rhus co...

  20. An ozone budget for the UK: using measurements from the national ozone monitoring network; measured and modelled meteorological data, and a 'big-leaf' resistance analogy model of dry deposition.

    PubMed

    Coyle, M; Smith, R; Fowler, D

    2003-01-01

    Data from the UK national air-quality monitoring network are used to calculate an annual mass budget for ozone (O3) production and loss in the UK boundary layer during 1996. Monthly losses by dry deposition are quantified from 1 km x 1 km scale maps of O(3) concentration and O(3) deposition velocities based on a big-leaf resistance analogy. The quantity of O(3) deposition varies from approximately 50 Gg-O(3) month(-1) in the winter to over 200 Gg-O(3) month(-1) in the summer when vegetation is actively absorbing O(3). The net O(3) production or loss in the UK boundary layer is found by selecting days when the UK is receiving "clean" Atlantic air from the SW to NW. In these conditions, the difference in O(3) concentration observed at Mace Head and a rural site on the east coast of the UK indicates the net O(3) production or loss within the UK boundary layer. A simple box model is then used to convert the concentration difference into a mass. The final budget shows that for most of the year the UK is a net sink for O(3) (-25 to -800 Gg-O(3) month(-1)) with production only exceeding losses in the photochemically active summer months (+45 Gg-O(3) month(-1)).

  1. Observations of ozone-induced foliar injury on black cherry (Prunus serotina, var. capuli) within the Desierto de Los Leones National Park, Mexico City.

    PubMed

    Skelly, J M; Savage, J E; de Bauer, M de L; Alvarado, D

    1997-01-01

    A survey for ozone-induced foliar injury of black cherry was conducted in mid-June 1995 within the Desierto de Los Leones National Park located southwest of Mexico City. Evaluations of the upper and lower tree crowns of 18 trees revealed evidence of significant upper surface stipple, leaf reddening and premature senescence on 72% of the trees. A general survey of an additional 169 trees disclosed that 41% exhibited similar symptoms. A gradient of increasing symptoms with increasing elevation was also evident. For the most part, asymptomatic trees were observed to be situated within well-shaded coves at the lower elevations with very few symptomatic trees present in these areas. PMID:15093455

  2. Identification of sources contributing to PM2.5 and ozone at elevated sites in the western U.S. by receptor analysis: Lassen Volcanic National Park, California, and Great Basin National Park, Nevada.

    PubMed

    VanCuren, Richard Tony; Gustin, Mae Sexauer

    2015-10-15

    The proposed revision of the United States (US) air quality standard for ozone will result in violations in sparsely populated remote rural areas in the Western US. Replicating air quality as measured at surface monitoring sites by modeling is particularly difficult in this region due to complex terrain, poorly represented in regional and global models, and uncertainties in emission rates and timing at all scales (locally as well as hundreds to thousands of km upwind). As an alternative method, a fully empirical, receptor-based scheme using in situ aerosol composition and simple meteorological variables to simulate ozone (O3) measurements was tested and found to produce O3 simulation results comparable in uncertainty to regional modeling, and supporting trajectory-based identification of O3 source regions. This approach was tested using two widely-separated (650 km) high altitude (approx. 2 km above sea level) monitoring sites, Lassen Volcanic National Park, in northern California (LAVO) and Great Basin National Park in eastern Nevada (GRBA). Comparing correlations between observed O3 and aerosols, and examining back-trajectories associated with peak concentrations for the two sites permitted distinguishing among local, distant North American, and Asian sources of particulate matter (PM2.5) and O3. This analysis indicates that anthropogenic enhancement of O3 at LAVO is primarily due to transport from Asia. Asia is also the dominant source of anthropogenic O3 at GRBA in spring, but regional North American sources of O3 appear to drive additional ozone peaks in late summer and fall at this more interior site.

  3. Identification of sources contributing to PM2.5 and ozone at elevated sites in the western U.S. by receptor analysis: Lassen Volcanic National Park, California, and Great Basin National Park, Nevada.

    PubMed

    VanCuren, Richard Tony; Gustin, Mae Sexauer

    2015-10-15

    The proposed revision of the United States (US) air quality standard for ozone will result in violations in sparsely populated remote rural areas in the Western US. Replicating air quality as measured at surface monitoring sites by modeling is particularly difficult in this region due to complex terrain, poorly represented in regional and global models, and uncertainties in emission rates and timing at all scales (locally as well as hundreds to thousands of km upwind). As an alternative method, a fully empirical, receptor-based scheme using in situ aerosol composition and simple meteorological variables to simulate ozone (O3) measurements was tested and found to produce O3 simulation results comparable in uncertainty to regional modeling, and supporting trajectory-based identification of O3 source regions. This approach was tested using two widely-separated (650 km) high altitude (approx. 2 km above sea level) monitoring sites, Lassen Volcanic National Park, in northern California (LAVO) and Great Basin National Park in eastern Nevada (GRBA). Comparing correlations between observed O3 and aerosols, and examining back-trajectories associated with peak concentrations for the two sites permitted distinguishing among local, distant North American, and Asian sources of particulate matter (PM2.5) and O3. This analysis indicates that anthropogenic enhancement of O3 at LAVO is primarily due to transport from Asia. Asia is also the dominant source of anthropogenic O3 at GRBA in spring, but regional North American sources of O3 appear to drive additional ozone peaks in late summer and fall at this more interior site. PMID:25864796

  4. 40 CFR 51.912 - What requirements apply for reasonably available control technology (RACT) and reasonably...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.912 What requirements apply for... reclassification under section 181(b)(3)) for the 8-hour ozone national ambient air quality standard, or July 9... than 27 months after designation for the 8-hour ozone NAAQS, except that for a State subject to...

  5. A search For Artic ozone

    NASA Astrophysics Data System (ADS)

    Maggs, William Ward

    Four atmospheric scientists took off with their instruments for Greenland last week, where they will try to see if depletion of stratospheric ozone in the Arctic can be detected as it has been in Antarctica since 1985.Members of the scientific team include Susan Solomon and George Mount of the Aeronomy Laboratory at the National Atmospheric and Oceanic Administration (NOAA) in Boulder, Colo., and Ryan Sanders and Roger Jakoubec of the Cooperative Institute for Research in Environmental Science in Norman, Okla. These four participated in previous National Ozone Expedition (NOZE) investigations at McMurdo Station in Antarctica that helped document the ozone “hole,” decreases of up to 50% in ozone during the early austral spring in September and October of the last 2 years (1986-1987).

  6. Nonmethane Hydrocarbons and Ozone in the Rural Southeast United States National Parks: A Model Sensitivity Analysis and Its Comparison with Measurement

    NASA Astrophysics Data System (ADS)

    Kang, D.; Aneja, V. P.; Mathur, R.; Ray, J. D.

    2001-12-01

    A comprehensive modeling analysis is conducted using the Multiscale Air Quality SImulation Platform (MAQSIP) focusing on nonmethane hydrocarbons and ozone in three southeast United States national parks for a 15-day time period (July 14th to July 29th, 1995) characterized by high O3 surface concentrations. Nine emission scenarios including the base scenario are analyzed. Model predictions are compared with and contrasted against observed data at the three locations for the same time period. Model predictions (base scenario) tend to give lower daily maximum O3 concentrations than observation by 10.8% at Cove Mountain, Great Smoke Mountains National Park (GRSM), 26.8% at Mammoth Cave National Park (MACA), and 17.6% at Big Meadows, Shenandoah National Park (SHEN). Overall mean ozone concentrations are very similar at GRSM and SHEN (observed data at MACA are not available). Model predicted concentrations of lumped paraffin compounds match the observed values on the same order, while the observed concentrations for other species (isoprene, ethene, surrogate olefin, surrogate toluene, and surrogate xylene) are usually an order of magnitude higher than the predictions. Sensitivity analyses indicate each location has its own characteristics in terms of the capacity of volatile organic compounds (VOCs) to produce O3, but a maximum VOC capacity point (MVCP) exists at all locations that changes the influence of VOCs on O3 from production to destruction. Analysis of individual model process budgets shows that more than 50% of daytime O3 concentrations at these rural locations are transported from other areas, local chemistry is the second largest contributor (13% to 42%), all other processes combined contribute less than 10% of the daytime O3 concentrations. Local emissions (>99%) are predominantly responsible for VOCs at all locations, while vertical diffusion (>70%) is the predominant process to move VOCs away from the modeling grid. Dry deposition ( ~ 10%) and chemistry (2

  7. Effects of Ozone and Peroxyacetyl Nitrate on Polar Lipids and Fatty Acids in Leaves of Morning Glory and Kidney Bean

    PubMed Central

    Nouchi, Isamu; Toyama, Susumu

    1988-01-01

    To compare the effects of ozone and peroxyacetyl nitrate (PAN) on leaf lipids, fatty acids and malondialdehyde (MDA), morning glory (Pharbitis nil Choisy cv Scarlet O'Hara) and kidney bean (Phaseolus vulgaris L. cv Gintebo) plants were exposed to either ozone (0.15 microliter per liter for 8 hours) or PAN (0.10 microliter per liter for up to 8 hours). Ozone increased phospholipids in morning glory and decreased in kidney bean at the initial stage (2-4 hours) of exposure, while it scarcely changed glycolipids, the unsaturated fatty acids, and MDA in both plants. A large reduction of glycolipids occurred 1 day after ozone exposure in both plants. PAN caused marked drops in phospholipids and glycolipids in kidney bean at relatively late stage (6-8 hours) of exposure, while it increased phosphatidic acid and decreased the unsaturated fatty acids, an increase which was accompanied by a large increase in MDA. These results suggest that ozone may not directly oxidize unsaturated fatty acids at the initial stage of exposure, but may alter polar lipid metabolism, particularly phospholipids. On the other hand, PAN may abruptly and considerably degrade phospholipids and glycolipids by peroxidation or hydrolysis at the late stage of exposure. The present study shows that ozone and PAN affect polar lipids in different manners. Images Fig. 2 Fig. 3 PMID:16666199

  8. Pulmonary Responses in Healthy Young Adults Exposed to Low Concentration of Ozone for 6.6 Hours with Mild Exercise

    EPA Science Inventory

    Rational: Recent studies have shown small but significant decreases in lung function following a prolonged exposure (6.6 hour) of healthy young adults to levels of ozone (0.08 ppm) near the current 8 hour standard. It is unclear, however, if such effects may be extended to concen...

  9. Tropospheric Enhancement of Ozone over the UAE

    NASA Astrophysics Data System (ADS)

    Abbasi, Naveed Ali; Majeed, Tariq; Iqbal, Mazhar; Kaminski, Jacek; Struzewska, Joanna; Durka, Pawel; Tarasick, David; Davies, Jonathan

    2015-04-01

    We use the Global Environmental Multiscale - Air Quality (GEM-AQ) model to interpret the vertical profiles of ozone acquired with ozone sounding experiments at the meteorological site located at the Abu Dhabi airport. The purpose of this study is to gain insight into the chemical and dynamical structures in the atmosphere of this unique subtropical location (latitude 24.45N; longitude 54.22E). Ozone observations for years 2012 - 2013 reveal elevated ozone abundances in the range from 70 ppbv to 120 ppbv near 500-400 hPa during summer. The ozone abundances in other seasons are much lower than these values. The preliminary results indicate that summertime enhancement in ozone is associated with the Arabian anticyclones centered over the Zagros Mountains in Iran and the Asir and Hijaz Mountain ranges in Saudi Arabia, and is consistent with TES observations of deuterated water. The model also shows considerable seasonal variation in the tropospheric ozone which is transported from the stratosphere by dynamical processes. The domestic production of ozone in the middle troposphere is estimated and compared GEM-AQ model. It is estimated that about 40-50% of ozone in the UAE is transported from the neighbouring petrochemical industries in the Gulf region. We will present ozone sounding data and GEM-AQ results including a discussion on the high levels of the tropospheric ozone responsible for contaminating the air quality in the UAE. This work is supported by National Research Foundation, UAE.

  10. Evaluation of microporous carbon filters as catalysts for ozone decomposition

    SciTech Connect

    Whinnery, L.; Coutts, D.; Shen, C.; Adams, R.; Quintana, C.; Showalter, S.

    1994-12-31

    Ozone is produced in small quantities in photocopiers and laser printers in the workplace and large quantities in industrial waste water treatment facilities. Carbon filters are commonly used to decompose this unwanted ozone. The three most important factors in producing a filter for this purpose are flow properties, efficiency, and cost. Most ozone decomposition applications require very low back-pressure at modest flow rates. The tradeoff between the number of pores and the size of the pores will be discussed. Typical unfiltered emissions in the workplace are approximately 1 ppm. The maximum permissible exposure limit, PEL, for worker exposure to ozone is 0.1 ppm over 8 hours. Several methods have been examined to increase the efficiency of ozone decomposition. Carbon surfaces were modified with catalysts, the surface activated, and the surface area was increased, in attempts to decompose ozone more effectively. Methods to reduce both the processing and raw material costs were investigated. Several sources of microporous carbon were investigated as ozone decomposition catalysts. Cheaper processing routes including macropore templating, faster drying and extracting methods were also studied.

  11. Synoptic and meteorological drivers of extreme ozone concentrations over Europe

    NASA Astrophysics Data System (ADS)

    Otero, Noelia Felipe; Sillmann, Jana; Schnell, Jordan L.; Rust, Henning W.; Butler, Tim

    2016-04-01

    The present work assesses the relationship between local and synoptic meteorological conditions and surface ozone concentration over Europe in spring and summer months, during the period 1998-2012 using a new interpolated data set of observed surface ozone concentrations over the European domain. Along with local meteorological conditions, the influence of large-scale atmospheric circulation on surface ozone is addressed through a set of airflow indices computed with a novel implementation of a grid-by-grid weather type classification across Europe. Drivers of surface ozone over the full distribution of maximum daily 8-hour average values are investigated, along with drivers of the extreme high percentiles and exceedances or air quality guideline thresholds. Three different regression techniques are applied: multiple linear regression to assess the drivers of maximum daily ozone, logistic regression to assess the probability of threshold exceedances and quantile regression to estimate the meteorological influence on extreme values, as represented by the 95th percentile. The relative importance of the input parameters (predictors) is assessed by a backward stepwise regression procedure that allows the identification of the most important predictors in each model. Spatial patterns of model performance exhibit distinct variations between regions. The inclusion of the ozone persistence is particularly relevant over Southern Europe. In general, the best model performance is found over Central Europe, where the maximum temperature plays an important role as a driver of maximum daily ozone as well as its extreme values, especially during warmer months.

  12. Evaluation of Global Model Simulation of Tropospheric Ozone from ECHAM6-HAMMOZ1 with Surface Measurements over the Mediterranean Region

    NASA Astrophysics Data System (ADS)

    Kaffashzadeh, Najmeh; Schultz, Martin G.; Lyapina, Olga; Schröder, Sabine; Stadtler, Scarlet

    2016-04-01

    Current chemistry transport models are generally successful in describing the principle features of the present-day global tropospheric ozone (O3) distribution, but they exhibit large differences of ozone concentrations over the Mediterranean region. The Mediterranean region can be perturbed by long-range pollution import from Northern Europe, North Africa and Asia, in addition to local emissions, which may all contribute to ozone concentrations in this area. Identifying the main drivers for Mediterranean ozone concentrations and understanding the reasons for the inter-model differences remain scientific challenges. To investigate the geographical distribution of tropospheric ozone over the Mediterranean, we analyze hourly surface ozone measurements from more than 1000 stations in the Tropospheric Ozone Assessment Report (TOAR) database and compare these to hourly model outputs from the global chemistry climate model ECHAM6-HAMMOZ1 for the year 2012. The daily maximum 8-hour running mean value of ozone mixing ratios is calculated for both model and observation and compared. The preliminary results show that the model captures many features of the ozone and its precursor concentrations in many regions of Europe throughout the year. However, it substantially underestimates ozone in the Po Valley region in summer and overestimates ozone over much of the Mediterranean region during spring. The reasons for this behavior will be investigated through detailed sensitivity studies with respect to VOC emissions, anthropogenic emissions, ozone deposition, specific chemical reactions, and long range-import of ozone and precursors.

  13. Total ozone trend over Cairo

    NASA Technical Reports Server (NTRS)

    Hassan, G. K. Y.

    1994-01-01

    A world wide interest in protecting ozone layer against manmade effects is now increasing. Assessment of the ozone depletion due to these activities depends on how successfully we can separate the natural variabilities from the data. The monthly mean values of total ozone over Cairo (30 05N) for the period 1968-1988, have been analyzed using the power spectral analysis technique. The technique used in this analysis does not depend on a pre-understanding of the natural fluctuations in the ozone data. The method depends on increasing the resolution of the spectral peaks in order to obtain the more accurate sinusoidal fluctuations with wavelength equal to or less than record length. Also it handles the possible sinusoidal fluctuations with wavelength equal to or less than record length. The results show that it is possible to detect some of the well known national fluctuations in the ozone record such as annual, semiannual, quasi-biennial and quasi-quadrennial oscillations. After separating the natural fluctuations from the ozone record, the trend analysis of total ozone over Cairo showed that a decrease of about -1.2% per decade has occurred since 1979.

  14. Impact to usaf from national and international restrictions on use of ozone-depleting substances. Final report, May 1990-April 1991

    SciTech Connect

    McCarson, T.D.; Tapscott, R.E.

    1995-04-01

    The objective of this project was to assess the impact on the U.S. Air Force (USAF) of national and international restrictions on the production and use of chlorofluorocarbons (CFCs), halons, and other substances believed to contribute to stratospheric ozone depletion. The Montreal Protocol (a United Nations agreement) and the U.S. Clean Air Act Amendments of 1990 place restrictions on the production and use of CFCs and halons with eventual phaseout of production by the year 2000. CFCs are widely used as refrigerants, cleaning solvents, sterilants, foam-blowing agents, and aerosol propellants. Halons are used primarily as fire and explosion suppression agents. The USAF uses CFCs and halons extensively in a variety of ways, many of which are critical to combat operations and capabilities. This project provides an assessment of the technologies for replacements or alternatives to the CFCs and halons being phased out and the resultant impact on USAF mission capabilities. Recommendations are made for actions necessary to mitigate the impact of CFC and halon production and use restrictions.

  15. Stomatal behavior of ozone-sensitive and -insensitive coneflowers (Rudbeckia laciniata var. digitata) in Great Smoky Mountains National Park.

    PubMed

    Grulke, N E; Neufeld, H S; Davison, A W; Roberts, M; Chappelka, A H

    2007-01-01

    * Morphological and physiological attributes were assessed to elucidate the underlying mechanisms of ozone (O(3)) sensitivity in a highly sensitive species, cutleaf coneflower (Rudbeckia laciniata var. digitata). * Foliage at the same height in the canopy on paired O(3)-sensitive and -insensitive cutleaf coneflowers was assessed for level of foliar symptoms, stomatal density, stomatal responsiveness to dynamic changes in light and leaf-to-air vapor pressure deficit (VPD), steady-state responses to light and CO(2), intrinsic transpirational efficiency, and plant water balance. * There were no morphological differences between the sensitivity types that might have contributed to greater O(3) uptake in sensitive individuals. Stomata of sensitive plants were less responsive than those of insensitive plants to experimentally increased and decreased light intensities, and to increased VPD. O(3)-insensitive plants had greater intrinsic transpirational efficiencies, greater maximum assimilation rates under saturating CO(2) and light, and greater carboxylation rates. * Different physiological attributes vary independently within an individual plant, which collectively confer sensitivity or insensitivity to O(3) injury. PMID:17176397

  16. Evaluation of emission control strategies to reduce ozone pollution in the Paso del Norte region using a photochemical air quality modeling system

    NASA Astrophysics Data System (ADS)

    Valenzuela, Victor Hugo

    Air pollution emissions control strategies to reduce ozone precursor pollutants are analyzed by applying a photochemical modeling system. Simulations of air quality conditions during an ozone episode which occurred in June, 2006 are undertaken by increasing or reducing area source emissions in Ciudad Juarez, Chihuahua, Mexico. Two air pollutants are primary drivers in the formation of tropospheric ozone. Oxides of nitrogen (NOx) and volatile organic compounds (VOC) undergo multiple chemical reactions under favorable meteorological conditions to form ozone, which is a secondary pollutant that irritates respiratory systems in sensitive individuals especially the elderly and young children. The U.S. Environmental Protection Agency established National Ambient Air Quality Standards (NAAQS) to limit ambient air pollutants such as ozone by establishing an 8-hour average concentration of 0.075 ppm as the threshold at which a violation of the standard occurs. Ozone forms primarily due reactions in the troposphere of NOx and VOC emissions generated primarily by anthropogenic sources in urban regions. Data from emissions inventories indicate area sources account for ˜15 of NOx and ˜45% of regional VOC emissions. Area sources include gasoline stations, automotive paint bodyshops and nonroad mobile sources. Multiplicity of air pollution emissions sources provides an opportunity to investigate and potentially implement air quality improvement strategies to reduce emissions which contribute to elevated ozone concentrations. A baseline modeling scenario was established using the CAMx photochemical air quality model from which a series of sensitivity analyses for evaluating air quality control strategies were conducted. Modifications to area source emissions were made by varying NOx and / or VOC emissions in the areas of particular interest. Model performance was assessed for each sensitivity analysis. Normalized bias (NB) and normalized error (NE) were used to identify

  17. The Antarctic Ozone Hole

    ERIC Educational Resources Information Center

    Jones, Anna E.

    2008-01-01

    Since the mid 1970s, the ozone layer over Antarctica has experienced massive destruction during every spring. In this article, we will consider the atmosphere, and what ozone and the ozone layer actually are. We explore the chemistry responsible for the ozone destruction, and learn about why conditions favour ozone destruction over Antarctica. For…

  18. Evaluation of the scientific basis for ozone/oxidants standards

    SciTech Connect

    Lee, S.D.; Lee, S.D.

    1985-01-01

    The author says ozone continues to be one of the nation's most important air pollution problems. A major component of smog, ozone can cause serious acute respiratory problems and may cause chronic disease as well. The author explains some of the present concerns about ozone and what is being done about them. He then discusses the future research priorities.

  19. Ozone Risk Assessment Utilities

    1999-08-10

    ORAMUS is a user-friendly, menu-driven software system that calculates and displays user-selected risk estimates for health effects attributable to short-term exposure to tropospheric ozone. Inputs to the risk assessment are estimates of exposure to ozone and exposure-response relationships to produce overall risk estimates in the form of probability distributions. Three fundamental models are included: headcount risk, benchmark risk, and hospital admissions. Exposure-response relationships are based on results of controlled human exposure studies. Exposure estimates aremore » based on the EPA''s probabilistic national ambient air quality standards (NAAQS) exposure model, pNEM/Osub3, which simulates air quality associated with attainment of alternative NAAQS. Using ORAMUS, risk results for 27 air quality scenarios, air quality in 9 urban areas, 33 health endpoints, and 4 chronic health endpoints can be calculated.« less

  20. Protecting the ozone layer.

    PubMed

    Munasinghe, M; King, K

    1992-06-01

    Stratospheric ozone layer depletion has been recognized as a problem by the Vienna Convention for the Protection of the Ozone Layer and the 1987 Montreal Protocol (MP). The ozone layer shields the earth from harmful ultraviolet radiation (UV-B), which is more pronounced at the poles and around the equator. Industrialized countries have contributed significantly to the problem by releasing chlorofluorocarbons (CFCs) and halons into the atmosphere. The effect of these chemicals, which were known for their inertness, nonflammability, and nontoxicity, was discovered in 1874. Action to deal with the effects of CFCs and halons was initiated in 1985 in a 49-nation UN meeting. 21 nations signed a protocol limiting ozone depleting substances (ODS): CFCs and halons. Schedules were set based on each country's use in 1986; the target phaseout was set for the year 2000. The MP restricts trade in ODSs and weights the impact of substances to reflect the extent of damage; i.e., halons are 10 times more damaging than CFCs. ODS requirements for developing countries were eased to accommodate scarce resources and the small fraction of ODS emissions. An Interim Multilateral Fund under the Montreal Protocol (IMFMP) was established to provide loans to finance the costs to developing countries in meeting global environmental requirements. The IMFMP is administered by the World Bank, the UN Environmental Program, and the UN Development Program. Financing is available to eligible countries who use .3 kg of ODS/person/year. Rapid phaseout in developed countries has occurred due to strong support from industry and a lower than expected cost. Although there are clear advantages to rapid phaseout, there were no incentives included in the MP for rapid phaseout. Some of the difficulties occur because the schedules set minimum targets at the lowest possible cost. Also, costs cannot be minimized by a country-specific and ODS-specific process. The ways to improve implementation in scheduling and

  1. Contribution of ozone to airborne aldehyde formation in Paris homes.

    PubMed

    Rancière, Fanny; Dassonville, Claire; Roda, Célina; Laurent, Anne-Marie; Le Moullec, Yvon; Momas, Isabelle

    2011-09-15

    Indoor aldehydes may result from ozone-initiated chemistry, mainly documented by experimental studies. As part of an environmental investigation included in the PARIS birth cohort, the aim of this study was to examine ozone contribution to airborne aldehyde formation in Paris homes. Formaldehyde, acetaldehyde and hexaldehyde levels, as well as styrene, nitrogen dioxide and nicotine concentrations, comfort parameters and carbon dioxide levels, were measured twice during the first year of life of the babies. Ambient ozone concentrations were collected from the closest background station of the regional air monitoring network. Traffic-related nitrogen oxide concentrations in front of the dwellings were estimated by an air pollution dispersion model. Home characteristics and families' way of life were described by questionnaires. Stepwise multiple linear regression models were used to link aldehyde levels with ambient ozone concentrations and a few aldehyde precursors involved in oxidation reactions, adjusting for other indoor aldehyde sources, comfort parameters and traffic-related nitrogen oxides. A 4 and 11% increase in formaldehyde and hexaldehyde levels was pointed out when 8-hour ozone concentrations increased by 20 μg/m(3). The influence of potential precursors such as indoor styrene level and frequent use of air fresheners, containing unsaturated volatile organic compounds as terpenes, was also found. Thus, our results suggest that ambient ozone can significantly impact indoor air quality, especially with regard to formaldehyde and hexaldehyde levels.

  2. Earth's Endangered Ozone

    ERIC Educational Resources Information Center

    Panofsky, Hans A.

    1978-01-01

    Included are (1) a discussion of ozone chemistry; (2) the effects of nitrogen fertilizers, fluorocarbons, and high level aircraft on the ozone layer; and (3) the possible results of a decreasing ozone layer. (MR)

  3. Total ozone measurements made with the Brewer ozone spectrophotometer during STOIC 1989

    NASA Astrophysics Data System (ADS)

    Kerr, J. B.; McElroy, C. T.

    1995-05-01

    The Canadian Atmospheric Environment Service participated in the Stratospheric Ozone Intercomparison Campaign (STOIC) by operating a Brewer ozone spectrophotometer at the Table Mountain Observatory from July 19 to August 2, 1989. Frequent direct Sun measurements of total column ozone were made throughout most days during the 2 weeks of the intercomparison. Results of the Brewer instrument total ozone measurements are given. They show that there is a diurnal variation of total ozone with values increasing on average by 6.6±2.4 Dobson units between early morning and late afternoon. Comparing the total ozone measurements with ozone concentration measurements made at ground level suggests that the daytime increase is a result of a buildup of surface ozone during the day. The total ozone measurements made by the Brewer instrument during STOIC are compared with total ozone measurements made by the National Oceanic and Atmospheric Administration (NOAA) Dobson instrument, the NASA/Wallops electrochemical concentration cell ozonesondes and the total ozone mapping spectrometer satellite instrument.

  4. Ozone crisis

    SciTech Connect

    Roan, S.

    1989-01-01

    The author presents an account of the depletion of the atmosphere's ozone layer since the discovery of the phenomenon 15 years ago. The book recounts the flight to ban chlorofluorocarbons (CFC's) and describes the science, the people, and the politics involved, up to the March 1988 international treaty restricting CFC production. It surveys the media's coverage, describes the struggle for remedies, and offers a prognosis for the future.

  5. Effect of photoperiodic pretreatments on symptom development in plants exposed to ozone

    SciTech Connect

    Godish, T.

    1980-01-01

    Results presented in this report on the effects of photoperiodic pretreatment on ozone sensitivity of plants are significantly different from the lone previous report on this subject. Juhren et al (5) studied the effects of photoperiodic pretreatments on sensitivity of pinto beans exposed to oxidants (presumably ozone). They reported that pinto bean plants were most sensitive to oxidants under short photoperiods (8 hours) and least sensitive to long photoperiods (16 hours). In studies of tomato and peas presented in this report, minimum sensitivity for tomato was observed under the 8 hour pretreatment; for peas minimum sensitivity was observed for the 8 and 10 hour pretreatments. Maximum sensitivity for tomato was observed for the 12-hour photoperiodic pretreatment; peas showed maximum sensitivity under the 14-hour photoperiod. 7 references, 1 table.

  6. Effects of ozone and peroxyacetyl nitrate on polar lipids and fatty acids in leaves of morning glory and kidney bean. [Pharbitis nil; Phaseolus vulgaris

    SciTech Connect

    Nouchi, Isamu; Toyama, Susumu Ochanomizu Univ., Tokyo )

    1988-07-01

    To compare the effects of ozone and peroxyacetyl nitrate (PAN) on leaf lipids, fatty acids and malondialdehyde (MDA), morning glory (Pharbitis nil Choisy cv Scarlet O'Hara) and kidney bean (Phaseolus vulgaris L. cv Gintebo) plants were exposed to either ozone (0.15 microliter per liter for 8 hours) or PAN (0.10 microliter per liter for up to 8 hours). Ozone increased phospholipids in morning glory and decreased in kidney bean at the initial stage (2-4 hours) of exposure, while it scarcely changed glycolipids, the unsaturated fatty acids, and MDA in both plants. A large reduction of glycolipids occurred 1 day after ozone exposure in both plants. PAN caused marked drops in phospholipids and glycolipids in kidney bean at relatively late stage (6-8 hours) of exposure, while it increased phosphatidic acid and decreased the unsaturated fatty acids, an increase which was accompanied by a large increase in MDA. These results suggest that ozone may not directly oxidize unsaturated fatty acids at the initial stage of exposure, but may alter polar lipid metabolism, particularly phospholipids. On the other hand, PAN may abruptly and considerably degrade phospholipids and glycolipids by peroxidation or hydrolysis at the late stage of exposure. The present study shows that ozone and PAN affect polar lipids in different manners.

  7. 77 FR 36163 - Determinations of Failure To Attain the One-Hour Ozone Standard by 2007, Current Attainment of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-18

    ... determining that the area previously failed to attain the one-hour ozone National Ambient Air Quality Standard... ozone monitoring data for 2008-2010. Quality-assured ozone monitoring data in the Air Quality System for... area previously failed to attain the one-hour ozone National Ambient Air Quality Standard (NAAQS)...

  8. Ozone NAAQS Review: Policy Assessment

    EPA Science Inventory

    Ozone is one of the six major air pollutants for which EPA has issued air quality criteria and established national ambient air quality standards (NAAQS) based on those criteria. The Clean Air Act (CAA) requires EPA to periodically review and revise, as appropriate, existing air...

  9. Comparative Effects of Gamma Irradiation and Ozone Treatment on Hygienic Quality of Korean Red Ginseng Powder

    NASA Astrophysics Data System (ADS)

    Byun, Myung-Woo; Yook, Hong-Sun; Kang, Il-Jun; Chung, Cha-Kwon; Kwon, Joong-Ho; Choi, Kang-Ju

    1998-06-01

    For the purpose of improving hygienic quality of Korean red ginseng powder, the comparative effects of gamma irradiation and ozone treatment on the microbial and physicochemical properties were investigated. Gamma irradiation at 7.5 kGy resulted in sterilization of total aerobic bacteria, molds and coliforms below detective levels, while ozone treatment for 8 hours up to 18 ppm did not sufficiently eliminate the microorganisms of the red ginseng powder. Physicochemical properties including compositions of the red ginseng saponin (ginsenosides) and fatty acids, pH and hydrogen doanting activity were not significantly changed by gamma irradiation, whereas, ozone treatment caused significant changes in fatty acid compositions, TBA value, pH, acidity and hydrogen donating activity. The results from this study led us to conclude that gamma irradiation was more effective than ozone treatment both for the improvement of hygienic quality and for the maintenance of physicochemical quality of red ginseng powder.

  10. Ozone Hole Over Antarctica

    NASA Technical Reports Server (NTRS)

    2002-01-01

    These images from the Total Ozone Mapping Spectrometer (TOMS) show the progressive depletion of ozone over Antarctica from 1979 to 1999. This 'ozone hole' has extended to cover an area as large as 10.5 million square miles in September 1998. The previous record of 10.0 million square miles was set in 1996. The Antarctic ozone hole develops each year between late August and early October. Regions with higher levels of ozone are shown in red. NASA and NOAA instruments have been measuring Antarctic ozone levels since the early 1970s. Large regions of depleted ozone began to develop over Antarctica in the early 1980s. Ozone holes of substantial size and depth are likely to continue to form during the next few years, scientists hope to see a reduction in ozone loss as levels of ozone-destroying CFCs (chlorofluorocarbons) are gradually reduced. Credit: Images by Greg Shirah, NASA Goddard Space Flight Center Scientific Visualization Studio

  11. The Antarctic ozone hole

    NASA Technical Reports Server (NTRS)

    Molina, Mario J.

    1988-01-01

    Observations of Antarctic ozone levels and the discovery of a hole in the Antarctic region are examined. The effects of chlorofluorocarbons (CFCs) on the level of stratospheric ozone are analyzed. Three cycles explaining the cause of ozone depletion in the poles are proposed. A comparison of field data and proposed depletion cycles reveals that the chemical origin of the ozone hole is due to CFCs. The potential global effects of the Antarctic ozone hole are discussed.

  12. Copenhagen delegates advance phaseout of ozone depleters

    SciTech Connect

    Kirschner, E.

    1992-12-09

    As expected, delegates at the United Nations Ozone Layer Conference in Copenhagen sped up ozone depleter phaseouts from the 1987 Montreal Protocol and the 1990 London amendments. The changes bring the worldwide production phaseout of chlorofluorocarbons (CFCs) and other ozone depleters in developed countries in line with U.S. and European plans announced earlier this year. Adjustments to the protocol, which are binding on the signatories, change the phaseout for CFC, carbon tetrachloride, and methyl chloroform production and consumption to January 1, 1996 from 2000. The 75% reduction of 1986 levels from CFCs by January 1, 1994 is a compromise between European pressure for an 85% cut and the US goal of 70%. Halon production is to end January 1, 1994, as anticipated. Developing countries continue to have a 10-year grace period. Friends of the Earth ozone campaign director Liz Cook counters that the phaseout dates were scheduled with concern for the chemical industry, not for the ozone layer.

  13. Ozone loss hits us where we live

    SciTech Connect

    Appenzeller, T.

    1991-11-01

    The news about Earth's ozone layer just keeps getting worse. Three weeks ago, NASA researchers reported that the ozone hole over the Antarctic hit a record depth this year. Now comes the United Nations Environment Program, together with the World Meteorological Organization, with an even more distressing assessment of the state of the ozone layer. For the first time, the 80-member UN panel said, measurements show the ozone shield is eroding over temperate latitudes in summer, exposing crops and people to a larger dose of ultraviolet light just when they are most vulnerable. For a small group of atmospheric modelers, though, the bad news is bittersweet. Four months ago researchers predicted summertime ozone losses of just the magnitude the UN panel has now reported: about 3% over the past decade for northern temperate latitudes. Ozone modelers are encouraged by the agreement, particularly because other models are now yielding the same result. The modeling effort was spurred by earlier measurements showing a serious erosion of ozone at midlatitudes, mainly in winter. In 1988, an analysis of data collected from the ground showed that ozone levels at the latitude of the US were dropping by about 1% to 3% per decade; last April, an analysis of measurements from the satellite-borne Total Ozone Mapping Spectrometer boosted that figure to between 4% and 5%. Those findings raised the question: What mechanisms could be driving the midlatitude losses The fact that the losses seemed to be concentrated in winter suggested one possibility. The winter ozone losses at the poles are driven by chemical reactions taking place on the surface of ice crystals in polar stratospheric clouds. Such clouds don't form at temperate latitudes. But some researchers suggested that masses of air already depleted in ozone or enriched in reactive chlorine by the chemistry in the polar clouds might be escaping to temperate latitudes during the winter.

  14. The evolution of ozone observed by UARS MLS in the 1992 late winter southern polar vortex

    SciTech Connect

    Manney, G.L.; Froidevaux, L.; Waters, J.W.; Elson, L.S.; Fishbein, E.F.; Zurek, R.W. ); Harwood, R.S.; Lahoz, W.A. )

    1993-06-18

    This paper presents initial data analysis of ozone distributions in the southern polar vortex region during the winter of 1992. The data comes from the microwave limb sounder on the upper atmosphere research satellite. The data provides never before available coverage of the polar stratosphere, and reveals the development of an ozone hole from column ozone data, changes in ozone mixing ratios in the lower stratosphere consistent with ozone destruction processes in the stratosphere, and evidence to support the transport of ozone toward the pole by tidal wave activity in the stratosphere. The ozone measurements are compared with the development of the polar vortex derived from national meteorological center data.

  15. Long-Term Exposure to Ozone and Life Expectancy in the United States, 2002 to 2008.

    PubMed

    Li, Chaoyang; Balluz, Lina S; Vaidyanathan, Ambarish; Wen, Xiao-Jun; Hao, Yongping; Qualters, Judith R

    2016-02-01

    Long-term exposure to ground-level ozone is associated with increased risk of morbidity and mortality. The association remains uncertain between long-term exposure to ozone and life expectancy. We assessed the associations between seasonal mean daily 8-hour maximum (8-hr max) ozone concentrations measured during the ozone monitoring seasons and life expectancy at birth in 3109 counties of the conterminous U.S. during 2002 to 2008. We used latent class growth analysis to identify latent classes of counties that had distinct mean levels and rates of change in ozone concentrations over the 7-year period and used linear regression analysis to determine differences in life expectancy by ozone levels. We identified 3 classes of counties with distinct seasonal mean daily 8-hr max ozone concentrations and rates of change. When compared with the counties with the lowest ozone concentrations, the counties with the highest ozone concentrations had 1.7- and 1.4-year lower mean life expectancy in males and females (both P < 0.0001), respectively. The associations remained statistically significant after controlling for potential confounding effects of seasonal mean PM2.5 concentrations and other selected environmental, demographic, socio-economic, and health-related factors (both P < 0.0001). A 5 ppb higher ozone concentration was associated with 0.25 year lower life expectancy in males (95% CI: -0.30 to -0.19) and 0.21 year in females (95% CI: -0.25 to -0.17). We identified 3 classes of counties with distinct mean levels and rates of change in ozone concentrations. Our findings suggest that long-term exposure to a higher ozone concentration may be associated with a lower life expectancy.

  16. Long-Term Exposure to Ozone and Life Expectancy in the United States, 2002 to 2008

    PubMed Central

    Li, Chaoyang; Balluz, Lina S.; Vaidyanathan, Ambarish; Wen, Xiao-Jun; Hao, Yongping; Qualters, Judith R.

    2016-01-01

    Abstract Long-term exposure to ground-level ozone is associated with increased risk of morbidity and mortality. The association remains uncertain between long-term exposure to ozone and life expectancy. We assessed the associations between seasonal mean daily 8-hour maximum (8-hr max) ozone concentrations measured during the ozone monitoring seasons and life expectancy at birth in 3109 counties of the conterminous U.S. during 2002 to 2008. We used latent class growth analysis to identify latent classes of counties that had distinct mean levels and rates of change in ozone concentrations over the 7-year period and used linear regression analysis to determine differences in life expectancy by ozone levels. We identified 3 classes of counties with distinct seasonal mean daily 8-hr max ozone concentrations and rates of change. When compared with the counties with the lowest ozone concentrations, the counties with the highest ozone concentrations had 1.7- and 1.4-year lower mean life expectancy in males and females (both P < 0.0001), respectively. The associations remained statistically significant after controlling for potential confounding effects of seasonal mean PM2.5 concentrations and other selected environmental, demographic, socio-economic, and health-related factors (both P < 0.0001). A 5 ppb higher ozone concentration was associated with 0.25 year lower life expectancy in males (95% CI: −0.30 to −0.19) and 0.21 year in females (95% CI: −0.25 to −0.17). We identified 3 classes of counties with distinct mean levels and rates of change in ozone concentrations. Our findings suggest that long-term exposure to a higher ozone concentration may be associated with a lower life expectancy. PMID:26886595

  17. Long-Term Exposure to Ozone and Life Expectancy in the United States, 2002 to 2008.

    PubMed

    Li, Chaoyang; Balluz, Lina S; Vaidyanathan, Ambarish; Wen, Xiao-Jun; Hao, Yongping; Qualters, Judith R

    2016-02-01

    Long-term exposure to ground-level ozone is associated with increased risk of morbidity and mortality. The association remains uncertain between long-term exposure to ozone and life expectancy. We assessed the associations between seasonal mean daily 8-hour maximum (8-hr max) ozone concentrations measured during the ozone monitoring seasons and life expectancy at birth in 3109 counties of the conterminous U.S. during 2002 to 2008. We used latent class growth analysis to identify latent classes of counties that had distinct mean levels and rates of change in ozone concentrations over the 7-year period and used linear regression analysis to determine differences in life expectancy by ozone levels. We identified 3 classes of counties with distinct seasonal mean daily 8-hr max ozone concentrations and rates of change. When compared with the counties with the lowest ozone concentrations, the counties with the highest ozone concentrations had 1.7- and 1.4-year lower mean life expectancy in males and females (both P < 0.0001), respectively. The associations remained statistically significant after controlling for potential confounding effects of seasonal mean PM2.5 concentrations and other selected environmental, demographic, socio-economic, and health-related factors (both P < 0.0001). A 5 ppb higher ozone concentration was associated with 0.25 year lower life expectancy in males (95% CI: -0.30 to -0.19) and 0.21 year in females (95% CI: -0.25 to -0.17). We identified 3 classes of counties with distinct mean levels and rates of change in ozone concentrations. Our findings suggest that long-term exposure to a higher ozone concentration may be associated with a lower life expectancy. PMID:26886595

  18. Ozone profiles above Palmer Station, Antarctica

    NASA Technical Reports Server (NTRS)

    Torres, Arnold L.; Brothers, George

    1988-01-01

    NASA's Goddard Space Flight Center/Wallops Flight Facility conducted a series of 52 balloon-borne measurements of vertical ozone profiles over the National Science Foundation (NSF) research facility at Palmer Station, Antarctica (64 deg 46 S, 64 deg 3 W) between August 9 and October 24, 1987. High resolution measurements were made from ground level to an average of 10 mb. While much variation was seen in the profile amounts of ozone, it is clear that a progressive depletion of ozone occurred during the measurement period, with maximum depletion taking place in the 17 to 19 km altitude region. Ozone partial pressures dropped by about 95 percent in this region. Shown here are plotted time dependences of ozone amounts observed at 17 km and at arbitrarily selected altitudes below (13 km) and above (24 km) the region of maximum depletion. Ozone partial pressure at 17 km is about 150nb in early August, and has decreased to less than 10nb in the minimums in October. The loss rate is of the order of 1.5 percent/day. In summary, a progressive depletion in stratospheric ozone over Palmer Station was observed from August to October, 1987. Maximum depletion occurred in the 17 to 19 km range, and amounted to 95 percent. Total ozone overburden decreased by up to 50 percent during the same period.

  19. Ambient ozone causes upper airways inflammation in children.

    PubMed

    Frischer, T M; Kuehr, J; Pullwitt, A; Meinert, R; Forster, J; Studnicka, M; Koren, H

    1993-10-01

    Ozone constitutes a major air pollutant in Western Europe. During the summer national air quality standards are frequently exceeded, which justifies concern about the health effects of ozone at ambient concentrations. We studied upper airways inflammation after ozone exposure in 44 children by repeated nasal lavages from May to October 1991. During this time period five to eight lavages were performed for each child. On 14 days following high ozone exposure (daily maximum > or = 180 micrograms/m3) 148 nasal lavages were performed, and on 10 days following low ozone exposure (daily maximum < or = 140 micrograms/m3) 106 nasal lavages were performed. A significant increase of intra-individual mean polymorphonuclear leukocytes (PMN) counts from low ozone days (median, 20.27 x 10(3)) to high ozone days (median, 27.38 x 10(3); p < 0.01) was observed. Concomitant with a decrease of ozone concentrations in the fall mean PMN counts showed a downward trend. Linear regression analysis of log-PMN counts yielded a significant effect for ozone (p = 0.017). In a subsample humoral markers of inflammation were measured for each child's highest and lowest exposure. A significant increase was observed for eosinophilic cationic protein (median, 77.39 micrograms/L on low ozone days versus 138.6 micrograms/L on high ozone days; p < 0.05). Thus we conclude that ozone at ambient concentrations initiates a reversible inflammatory response of the upper airways in normal children.

  20. Antarctic Ozone Hole, 2000

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Each spring the ozone layer over Antarctica nearly disappears, forming a 'hole' over the entire continent. The hole is created by the interaction of some man-made chemicals-freon, for example-with Antarctica's unique weather patterns and extremely cold temperatures. Ozone in the stratosphere absorbs ultraviolet radiation from the sun, thereby protecting living things. Since the ozone hole was discovered many of the chemicals that destroy ozone have been banned, but they will remain in the atmosphere for decades. In 2000, the ozone hole grew quicker than usual and exceptionally large. By the first week in September the hole was the largest ever-11.4 million square miles. The top image shows the average total column ozone values over Antarctica for September 2000. (Total column ozone is the amount of ozone from the ground to the top of the atmosphere. A relatively typical measurement of 300 Dobson Units is equivalent to a layer of ozone 0.12 inches thick on the Earth's surface. Levels below 220 Dobson Units are considered to be significant ozone depletion.) The record-breaking hole is likely the result of lower than average ozone levels during the Antarctic fall and winter, and exceptionally cold temperatures. In October, however (bottom image), the hole shrank dramatically, much more quickly than usual. By the end of October, the hole was only one-third of it's previous size. In a typical year, the ozone hole does not collapse until the end of November. NASA scientists were surprised by this early shrinking and speculate it is related to the region's weather. Global ozone levels are measured by the Total Ozone Mapping Spectrometer (TOMS). For more information about ozone, read the Earth Observatory's ozone fact sheet, view global ozone data and see these ozone images. Images by Greg Shirah, NASA GSFC Scientific Visualization Studio.

  1. Tunable Diode Laser Heterodyne Spectrophotometry of Ozone

    NASA Technical Reports Server (NTRS)

    Fogal, P. F.; McElroy, C. T.; Goldman, A.; Murcray, D. G.

    1988-01-01

    Tunable diode laser heterodyne spectrophotometry (TDLHS) has been used to make extremely high resolution (less than 0.0005/ cm) solar spectra in the 9.6 micron ozone band. Observations have shown that a signal-to-noise ratio of 95 : 1 (35% of theoretical) for an integration time of 1/8 second can be achieved at a resolution of 0.0005 wavenumbers. The spectral data have been inverted to yield a total column amount of ozone, in good agreement with that. measured at the nearby National Oceanographic and Atmospheric Administration (NOAA) ozone monitoring facility in Boulder, Colorado.

  2. Gridded global surface ozone metrics for atmospheric chemistry model evaluation

    NASA Astrophysics Data System (ADS)

    Sofen, E. D.; Bowdalo, D.; Evans, M. J.; Apadula, F.; Bonasoni, P.; Cupeiro, M.; Ellul, R.; Galbally, I. E.; Girgzdiene, R.; Luppo, S.; Mimouni, M.; Nahas, A. C.; Saliba, M.; Tørseth, K.

    2016-02-01

    The concentration of ozone at the Earth's surface is measured at many locations across the globe for the purposes of air quality monitoring and atmospheric chemistry research. We have brought together all publicly available surface ozone observations from online databases from the modern era to build a consistent data set for the evaluation of chemical transport and chemistry-climate (Earth System) models for projects such as the Chemistry-Climate Model Initiative and Aer-Chem-MIP. From a total data set of approximately 6600 sites and 500 million hourly observations from 1971-2015, approximately 2200 sites and 200 million hourly observations pass screening as high-quality sites in regionally representative locations that are appropriate for use in global model evaluation. There is generally good data volume since the start of air quality monitoring networks in 1990 through 2013. Ozone observations are biased heavily toward North America and Europe with sparse coverage over the rest of the globe. This data set is made available for the purposes of model evaluation as a set of gridded metrics intended to describe the distribution of ozone concentrations on monthly and annual timescales. Metrics include the moments of the distribution, percentiles, maximum daily 8-hour average (MDA8), sum of means over 35 ppb (daily maximum 8-h; SOMO35), accumulated ozone exposure above a threshold of 40 ppbv (AOT40), and metrics related to air quality regulatory thresholds. Gridded data sets are stored as netCDF-4 files and are available to download from the British Atmospheric Data Centre (doi: 10.5285/08fbe63d-fa6d-4a7a-b952-5932e3ab0452). We provide recommendations to the ozone measurement community regarding improving metadata reporting to simplify ongoing and future efforts in working with ozone data from disparate networks in a consistent manner.

  3. Ground-level ozone in China: distribution and effects on crop yields.

    PubMed

    Wang, Xiaoke; Manning, William; Feng, Zongwei; Zhu, Yongguan

    2007-05-01

    Rapid economic development and an increasing demand for food in China have drawn attention to the role of ozone at pollution levels on crop yields. Some assessments of ozone effects on crop yields have been carried out in China. Determination of ozone distribution by geographical location and resulting crop loss estimations have been made by Chinese investigators and others from abroad. It is evident that surface level ozone levels in China exceed critical levels for occurrence of crop losses. Current levels of information from ozone dose/response studies are limited. Given the size of China, existing ozone monitoring sites are too few to provide enough data to scale ozone distribution to a national level. There are large uncertainties in the database for ozone effects on crop loss and for ozone distribution. Considerable research needs to be done to allow accurate estimation of crop losses caused by ozone in China. PMID:16973249

  4. User's guide for SBUV/TOMS ozone derivative products

    NASA Technical Reports Server (NTRS)

    Fleig, A. J.; Wellemeyer, C.; Oslik, N.; Lee, D.; Miller, J.; Magatani, R.

    1984-01-01

    A series of products are available derived from the total-ozone and ozone vertical profile results for the Solar Backscattered Ultraviolet/Total-Ozone Mapping Spectrometer (SBUV/TOMS) Nimbus-7 operation. Products available are (1) orbital height-latitude cross sections of the SBUV profile data, (2) daily global total ozone contours in polar coordinates, (3) daily averages of total ozone in global 5x5 degree latitude-longitude grid, (4) daily, monthly and quarterly averages of total ozone and profile data in 10 degree latitude zones, (5) tabular presentation of zonal means, (6) daily global total ozone and profile contours in polar coordinates. The ""Derivative Products User's Guide'' describes each of these products in detail, including their derivation and presentation format. Information is provided on how to order the tapes and microfilm from the National Space Science Data Center.

  5. Antarctic Ozone Hole on September 17, 2001

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Satellite data show the area of this year's Antarctic ozone hole peaked at about 26 million square kilometers-roughly the size of North America-making the hole similar in size to those of the past three years, according to scientists from NASA and the National Oceanic and Atmospheric Administration (NOAA). Researchers have observed a leveling-off of the hole size and predict a slow recovery. Over the past several years the annual ozone hole over Antarctica has remained about the same in both its size and in the thickness of the ozone layer. 'This is consistent with human-produced chlorine compounds that destroy ozone reaching their peak concentrations in the atmosphere, leveling off, and now beginning a very slow decline,' said Samuel Oltmans of NOAA's Climate Monitoring and Diagnostics Laboratory, Boulder, Colo. In the near future-barring unusual events such as explosive volcanic eruptions-the severity of the ozone hole will likely remain similar to what has been seen in recent years, with year-to-year differences associated with meteorological variability. Over the longer term (30-50 years) the severity of the ozone hole in Antarctica is expected to decrease as chlorine levels in the atmosphere decline. The image above shows ozone levels on Spetember 17, 2001-the lowest levels observed this year. Dark blue colors correspond to the thinnest ozone, while light blue, green, and yellow pixels indicate progressively thicker ozone. For more information read: 2001 Ozone Hole About the Same Size as Past Three Years. Image courtesy Greg Shirah, GSFC Scientific Visualization Studio, based on data from the TOMS science team

  6. Ozone-induced changes in the expression of the genes encoding regulatory enzymes for polyamine, ethylene and phenylpropanoid metabolisms in ozone tolerant and sensitive birch (Betula pendula Roth) clones

    SciTech Connect

    Talvinen, J.; Pellinen, R.; Eloranta, T.; Kangasjaervi, J. ); Julkunen-Tiitto, R. ); Karjalainen, R. )

    1993-05-01

    Increase in the atmospheric ozone concentration has been shown to affect plant growth in several ways; from decreased photosynthetic activity to visible dames and in some extreme situations even to tissue death. Plants protect themselves from the damaging effect of ozone by inducing several physiological reactions. For example, increases in ethylene production, polyamine and phenylpropanoid synthesis have been observed in stress reaction induced by increased atmospheric ozone. similar changes, which are often called general stress reactions, are induced by several other biotic and which are often called general stress reactions, are induced by several other biontic and abiotic factors, e.g., plant pathogens. It has been shown previously that the production of stress ethylene can partly be responsible for the ozone damage formation in plants. Induction of stress-polyamine synthesis can prevent ethylene formation and is higher in some ozone-tolerant plants. We have exposed ozone sensitive and resistant birch clones to ozone (150 ppb. 8 hours) to analyze ozone-induced changes in the phenylpropanoid and polyamine metabolisms and gene expression. The polyamine and phenylpropanoid contents of the experimental material are currently being analyzed and the results will be presented. We have also cloned by PCR gene probes for birch ACC-synthase, arginine decarboxylase (ADC) and phenylalanine ammoniumlyase (PAL) genes. Results will be presented where the probes have been used to analyze ozone-induced expression of the genes in the birch clones.

  7. Ozone Trend Detectability

    NASA Technical Reports Server (NTRS)

    Campbell, J. W. (Editor)

    1981-01-01

    The detection of anthropogenic disturbances in the Earth's ozone layer was studied. Two topics were addressed: (1) the level at which a trend in total ozoning is detected by existing data sources; and (2) empirical evidence in the prediction of the depletion in total ozone. Error sources are identified. The predictability of climatological series, whether empirical models can be trusted, and how errors in the Dobson total ozone data impact trend detectability, are discussed.

  8. Ozone Antimicrobial Efficacy

    EPA Science Inventory

    Ozone is a potent germicide that has been used extensively for water purification. In Europe, 90 percent of the municipal water systems are treated with ozone, and in France, ozone has been used to treat drinking water since 1903. However, there is limited information on the bioc...

  9. Ozone drinking water treatment handbook

    SciTech Connect

    Rice, R.G.

    1990-01-01

    This book explains how ozone can be used to provide primary disinfection, while minimizing halogenated by-products. This is of use to those who design pilot plant studies in full scale ozone plants-and those who employ ozone and regulatory personnel. Detailed section on components of an ozonization system outlines feed gas preparation (air and oxygen), ozone generation, ozone contacting, ozone off gas destruction, monitoring and control of ozonation systems, engineering aspects of ozone, cost factors in ozone technology, case histories (European and U.S.).

  10. User's guide for the Solar Backscattered Ultraviolet (SBUV) instrument first year ozone-S data set

    NASA Technical Reports Server (NTRS)

    Fleig, A. J.; Klenk, K. F.; Bhartia, P. K.; Gordon, D.; Schneider, W. H.

    1982-01-01

    Total-ozone and ozone vertical profile results for Solar Backscattered Ultraviolet/Total Ozone Mapping Spectrometer (SBUV/TOMS) Nimbus 7 operation from November 1978 to November 1979 are available. The algorithm used have been thoroughly tested, the instrument performance has been examined in details, and the ozone results have been compared with Dobson, Umkehr, balloon, and rocket observations. The accuracy and precision of the satellite ozone data are good to at least within the ability of the ground truth to check and are self-consistent to within the specifications of the instrument. The 'SBUV User's Guide' describes the SBUV experiment and algorithms used. Detailed information on the data available on computer tape is provided including how to order tapes from the National Space Science Data Center.

  11. The 1996 Paso del Norte Ozone Study: analysis of meteorological and air quality data that influence local ozone concentrations.

    PubMed

    MacDonal, C P; Roberts, P T; Main, H H; Dye, T S; Coe, D L; Yarbrough, J

    2001-08-10

    The 1996 Paso del Norte Ozone Study and subsequent data analyses were implemented to develop an understanding of the chemical and physical processes which lead to high concentrations of ozone in the Paso del Norte study area which includes El Paso County, Texas, Sunland Park, New Mexico, and Ciudad Juárez, Mexico. Both the data and data analysis results are being used to support photochemical grid modeling. El Paso County and Sunland Park fail to meet the National Ambient Air Quality Standard (NAAQS) for ozone, and neighboring Ciudad Juárez fails to meet the Mexican ambient standard for ozone. This paper summarizes the measurement campaigns of the 1996 Paso del Norte Ozone Study and the findings and conclusions that arose from subsequent data analyses. Data analyses showed that high ozone concentrations resulted from a combination of conditions, including high surface temperatures, strong sunlight with few clouds, light surface winds and high concentrations of ozone precursors at ground level in the morning, and slow convective boundary layer (CBL) growth. Synoptic-scale meteorological conditions observed during high ozone episodes included an aloft high-pressure system and aloft warming. Aloft carryover of ozone and ozone precursors did not significantly contribute to high concentrations of ozone at the surface.

  12. Impact of biogenic emissions on ozone and fine particles over Europe: Assessing the effect of temperature increase and the role of anthropogenic NOx emissions reduction

    NASA Astrophysics Data System (ADS)

    Tagaris, Efthimios; Sotiropoulou, Rafaella-Eleni P.; Gounaris, Nikos; Andronopoulos, Spyros; Vlachogiannis, Diamando

    2014-05-01

    The role of biogenic emissions on ozone and PM2.5 levels over Europe is assessed for July 2006 using the CMAQ modeling system. Biogenic emissions are simulated to increase the daily maximum 8 hour ozone (Max8hrO3) mixing ratios and to decrease PM2.5 average concentrations over Europe. Since climate change will lead to higher temperatures increasing subsequently biogenic emissions, sensitivity analysis to temperature is performed. Higher temperatures suggest an average increase in Max8hrO3 mixing ratios over Europe by about 3% and an average decrease in PM2.5 concentrations by about 6%, related to a temperature increase by 3 K degrees. Temperature increases are simulated, also, to increase the organic part of PM2.5 and to decrease the inorganic one on average over Europe. In order to examine if abatement measures for anthropogenic emissions could offset ozone increases in a warmer environment and their effect on PM2.5 concentrations, simulation with a domain wide reduction of anthropogenic NOx emissions by 10% is performed. This is estimated to reduce Max8hrO3 mixing ratios on average over Europe, however, in VOCs limited areas there is an increase. The reduction in anthropogenic NOx emissions is simulated to reduce PM2.5 concentrations on average over Europe enhancing the reduction simulated in a warmer environment but further modifying PM2.5 component concentrations. This work was supported by the National Strategic Reference Framework (NSRF) 2007-2013 grand No 09SYN-31-667.

  13. Projections of Future Summertime Ozone over the U.S.

    SciTech Connect

    Pfister, G. G.; Walters, Stacy; Lamarque, J. F.; Fast, Jerome D.; Barth, Mary; Wong, John; Done, James; Holland, Greg; Bruyere, Cindy

    2014-05-05

    This study uses a regional fully coupled chemistry-transport model to assess changes in surface ozone over the summertime U.S. between present and a 2050 future time period at high spatial resolution (12 km grid spacing) under the SRES A2 climate and RCP8.5 anthropogenic pre-cursor emission scenario. The impact of predicted changes in climate and global background ozone is estimated to increase surface ozone over most of the U.S; the 5th - 95th percentile range for daily 8-hour maximum surface ozone increases from 31-79 ppbV to 30-87 ppbV between the present and future time periods. The analysis of a set of meteorological drivers suggests that these mostly will add to increasing ozone, but the set of simulations conducted does not allow to separate this effect from that through enhanced global background ozone. Statistically the most robust positive feedbacks are through increased temperature, biogenic emissions and solar radiation. Stringent emission controls can counteract these feedbacks and if considered, we estimate large reductions in surface ozone with the 5th-95th percentile reduced to 27-55 ppbV. A comparison of the high-resolution projections to global model projections shows that even though the global model is biased high in surface ozone compared to the regional model and compared to observations, both the global and the regional model predict similar changes in ozone between the present and future time periods. However, on smaller spatial scales, the regional predictions show more pronounced changes between urban and rural regimes that cannot be resolved at the coarse resolution of global model. In addition, the sign of the changes in overall ozone mixing ratios can be different between the global and the regional predictions in certain regions, such as the Western U.S. This study confirms the key role of emission control strategies in future air quality predictions and demonstrates the need for considering degradation of air quality with future

  14. Tropospheric Ozone Pollution from Space: New Views from the TOMS (Total Ozone Mapping Spectrometer) Instrument

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Hudson, Robert D.; Frolov, Alexander D.; Witte, Jacquelyn C.; Kucsera, Tom L.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    ("paradoxes") in tropical tropospheric ozone and smoke aerosol in regions of greatest tropical biomass burning [Thompson et at., 1996;2000b]. (4) Trans-boundary pollution tracking. With an air parcel (trajectory) model, smoke aerosol and ozone and dust plumes can be tracked across oceans (e.g., Asia to North America; North America to Europe) and national boundaries, e.g. Indonesia to Singapore and Malaysia during the 1997 ENSO fires.

  15. Monitoring and future projections of the Antarctic Ozone Hole using the new Ozone Mapping and Profiler Suite (OMPS)

    NASA Astrophysics Data System (ADS)

    Kramarova, N. A.; Newman, P. A.; Nash, E. R.; Bhartia, P. K.; McPeters, R. D.; Rault, D. F.; Seftor, C. J.; Xu, P.

    2013-12-01

    Using the new Ozone Mapping and Profiler Suite (OMPS), launched October 2011 on board the Suomi National Polar-orbiting Partnership satellite, we have studied the structure and evolution of the 2012 and 2013 ozone holes. The 1st ozone hole observations by OMPS began in 2012. We quality check the OMPS measurements by comparing to other satellite instruments (Aura MLS, OMI and SBUV) and ozone sonde balloon measurements. The comparisons reveal that OMPS is producing excellent Antarctic ozone hole information, and, thus, OMPS data can be used to continue the historical record of Antarctic ozone observations. In 2012 the ozone hole developed quite normally in the August to-late September 2012 period, but disappeared much more rapidly during the late-September to November period than it would be expected in a normal year. This resulted in the second weakest ozone hole observed since 1988. Some have suggested that the rapid 2012 disappearance is evidence that the Montreal Protocol is working. However, the development of the ozone hole in August and September is largely driven by chlorine and bromine from human-produced compounds, and the normal development of the ozone hole in August-September 2012 suggests that chlorine and bromine levels were roughly the same as previous years. At the same time, observations from meteorological data show that there were stronger than average weather systems, faster warming during the September -November period, and stronger vertical motions, that led to a rapid decay of the 2012 ozone hole. Hence, the weak ozone hole of 2012 is not evidence that the Montreal Protocol has impacted the ozone hole. The characteristics of the 2013 ozone hole, as observed by OMPS, will also be shown in the presentation. Model predictions suggest that the ozone hole will begin showing signs of recovery in about 2018, and it will be fully recovered back to 1980 levels in about 2065. We will update projections of the ozone hole recovery using a parametric model

  16. Ozone and the stratosphere

    NASA Technical Reports Server (NTRS)

    Shimazaki, Tatsuo

    1987-01-01

    It is shown that the stratospheric ozone is effective in absorbing almost all radiation below 300 nm at heights below 300 km. The distribution of global ozone in the troposphere and the lower stratosphere, and the latitudinal variations of the total ozone column over four seasons are considered. The theory of the ozone layer production is discussed together with catalytic reactions for ozone loss and the mechanisms of ozone transport. Special attention is given to the anthropogenic perturbations, such as SST exhaust gases and freon gas from aerosol cans and refrigerators, that may cause an extensive destruction of the stratospheric ozone layer and thus have a profound impact on the world climate and on life.

  17. Correlation of DIAL Ozone Observations with Lightning

    NASA Technical Reports Server (NTRS)

    Peterson, Harold S.; Kuang, Shi; Koshak, William J.; Newchurch, Mike

    2014-01-01

    The purpose of this project is to see whether ozone maxima measured by the DIfferential Absorption Lidar (DIAL) instrument in Huntsville, AL may be traced back to lightning events occurring 24-48 hours beforehand. The methodology is to start with lidar measurements of ozone from DIAL. The HYbrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model is then used to determine the origin of these ozone maxima 24-48 hours prior. Data from the National Lightning Detection Network (NLDN) are used to examine the presence/absence of lightning along the trajectory. This type of analysis suggests that lightning-produced NOx may be responsible for some of the ozone maxima over Huntsville.

  18. Correlation of DIAL Ozone Observations with Lightning

    NASA Technical Reports Server (NTRS)

    Peterson, Harold; Kuang, Shi; Koshak, William; Newchurch, Michael

    2013-01-01

    The purpose of this project is to see whether ozone maxima measured by the DIfferential Absorption Lidar (DIAL) instrument in Huntsville, AL may be traced back to lightning events occurring 24- 48 hours beforehand. The methodology is to start with lidar measurements of ozone from DIAL as well as ozonesonde measurements. The HYbrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model is then used to determine the origin of these ozone maxima 24-48 hours prior. Data from the National Lightning Detection Network (NLDN) are used to examine the presence/absence of lightning along the trajectory. This type of analysis suggests that lightning-produced NOx may be responsible for some of the ozone maxima over Huntsville.

  19. Impacts of Asian emissions on ozone air quality over western U.S. in spring and summer

    NASA Astrophysics Data System (ADS)

    Lin, M.; Fiore, A. M.; Cooper, O. R.; Horowitz, L. W.; Naik, V.; Wyman, B.; Alvarez, R. J., II; Banta, R. M.; Bahreini, R.; Holloway, J. S.; Hardesty, R.; Johnson, B. J.; Langford, A. O.; Middlebrook, A. M.; Oltmans, S. J.; Pollack, I. B.; Ryerson, T. B.; Senff, C. J.; Wiedinmyer, C.; Ziemke, J. R.

    2010-12-01

    conduct AM3 model simulations at multiple horizontal resolutions (currently ~2 degrees with a target resolution of 0.25 degrees) to gauge the relative importance of synoptic (e.g. large-scale subsidence over the western U.S. following warm conveyor belt transport in spring) vs. meso-scale (e.g. surface-heating driven mountain-valley flow and land-sea breezes in summer) processes in controlling daily to seasonal variability of Asian pollution in the free troposphere and subsequent mixing into the western U.S. boundary layer. We will further explore the role of Asian emissions in exceedances of the 8-hour 70 ppbv ozone standard in the state of California.

  20. Assessing control strategies for ground level ozone

    NASA Astrophysics Data System (ADS)

    Sule, Neelesh Vijay

    2009-12-01

    combination of targeted control strategies that brings the region into attainment for the 8-hour ozone. Each day was optimized individually in sequence. In order to demonstrate applicability of the DMF 5 days (August 15, 16, 17, 18 and 19) of the episode were optimized. Although the optimization identified the key sources, time periods, and control strategies, the existing controls on these sources were not adequate to bring the region in attainment. Further reductions at these sources beyond the existing list of TCEQ/NCTCOG control strategies were required. Further modifications in the DMF for DFW were suggested to improve its performance.

  1. Evidence of the mid-latitude impact of Antarctic ozone depletion

    NASA Technical Reports Server (NTRS)

    Atkinson, Roger J.; Matthews, W. Andrew; Newman, Paul A.; Plumb, R. Alan

    1989-01-01

    Record low ozone values found over Australia and New Zealand during December 1987 following the record low Antarctic values of October 1987 are analyzed. The sudden decline of ozone amounts in midmonth rule out photochemical effects as a cause and permit the underlying processes to be investigated on a case study basis. Using data from ozone sondes, radiosondes, the Nimbus-7 total ozone mapping spectrometer, and meteorological analyses from the National Meteorological Center, it is argued that these low values resulted from transport of ozone-poor air from higher latitudes. Thus, it seems that the chemical destruction of ozone over Antarctica in early spring is having an impact on lower latitudes.

  2. Interagency cooperative scientific program to investigate antarctic ozone hole

    SciTech Connect

    Not Available

    1987-09-01

    NASA, The Department of Commerce National Oceanic and Atmospheric Administration, the National Science Foundation and its National Center for Atmospheric Research, and the Chemical Manufacturer's Association have announced a cooperative investigation of the Antarctic ozone hole. The Airborne Antarctic Ozone Experiment will fly specially instrumented NASA ER-2 and DC-8 aircraft into the Antarctic ozone hole from August 17 through September 29. The experiments have been designed not only to test existing Antarctic ozone hole theories but to provide for a wide base of high quality atmospheric data in the event that none of the current hypotheses proves to be adequate. This experiment is prompted by recent observations that have shown a dramatic and unexpected downward trend in the amount of ozone in a column of air over the Antarctic in the period between late winter and early spring.

  3. AIR QUALITY CRITERIA FOR OZONE AND RELATED PHOTOCHEMICAL OXIDANTS

    EPA Science Inventory

    The Clean Air Act requires periodic (5-year) update revision of criteria and National Ambient Air Quality Standards (NAAQS) for Ozone. The previous revision of the criteria contained in the Air Quality Criteria Document (AQCD) for Ozone and Related Photochemical Oxidants was co...

  4. 40 CFR 52.2428 - Control Strategy: Carbon monoxide and ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ozone National Ambient Air Quality Standard (NAAQS). This determination, in accordance with 40 CFR 51... ozone. 52.2428 Section 52.2428 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control Strategy: Carbon monoxide and ozone. (a) Determination—EPA has determined that, as of November...

  5. 40 CFR 52.2428 - Control Strategy: Carbon monoxide and ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ozone National Ambient Air Quality Standard (NAAQS). This determination, in accordance with 40 CFR 51... ozone. 52.2428 Section 52.2428 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control Strategy: Carbon monoxide and ozone. (a) Determination—EPA has determined that, as of November...

  6. 40 CFR 52.2428 - Control Strategy: Carbon monoxide and ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ozone National Ambient Air Quality Standard (NAAQS). This determination, in accordance with 40 CFR 51... ozone. 52.2428 Section 52.2428 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control Strategy: Carbon monoxide and ozone. (a) Determination—EPA has determined that, as of November...

  7. Effects of nitrogen oxide emission controls on Eastern US surface ozone: A comparison between urban cores and rural background sites

    NASA Astrophysics Data System (ADS)

    Rieder, Harald E.; Fiore, Arlene M.

    2016-04-01

    Nitrogen oxide (NOx) emission controls have led to improved air quality over the past two decades, particularly over the Eastern US. In recent work we quantified the effects of the efforts to abate surface ozone (O3) pollution under the NOx State Implementation Plan (NOx SIP Call) for Eastern US background sites (available from the Clean Air Status and Trends Network (CASTNET)) using methods from statistical extreme value theory (Rieder et al., 2013). Our analysis showed that the number of summer (JJA) days above the US national ambient air quality standard (NAAQS) declined on average by a factor of two between 1988-1998 and 1999-2009 and that probabilistic 1-yr O3 return values declined by about 10 ppb between these two time periods. Here we extend the analysis to observations available from the US EPA Air Quality System (AQS), comprising sites ranging from polluted urban cores to rural sites. We focus on changes in (i) the seasonal and annual average number of days with maximum daily 8-hour average surface O3 above the NAAQS and (ii) probabilistic O3 return values following the NOx SIP Call. Particular focus is given on similarities and differences in surface O3 responses on regional to local level and on contrasting urban cores and rural background sites. References: Rieder H.E., Fiore A.M., Polvani L.M., Lamarque J.-F., Fang Y. (2013): Changes in the frequency and return level of high ozone pollution events over the Eastern United States following emission controls, Environ. Res. Lett., 8, 014012, 2013.

  8. Assessment of the economic effects of ozone on US agriculture

    SciTech Connect

    Adams, R.M.; Hamilton, S.A.; McCarl, B.A.

    1985-01-01

    Past attempts to measure the economic consequences of ozone on agriculture have been based on limited plant science information. This paper reports on an economic assessment of ozone on US agriculture using recent crop response data from the National Crop Loss Assessment Network (NCLAN). The results are derived from a US agricultural sector model that includes major crop and livestock production as well as domestic consumption, livestock feeding and export uses. The economic effects of four hypothetical ambient ozone levels are investigated. The analysis indicates that the benefits to society of moderate (25%) ozone reductions are approximately $1.7 billion. A 25% increase in ozone pollution results in cost (negative benefits) of $2.1 billion. These estimates do not reflect compliance costs of achieving the ozone changes and hence are not net benefits.

  9. Characterizing the Vertical Processes of Ozone in Colorado's Front Range Using the GSFC Ozone DIAL

    NASA Astrophysics Data System (ADS)

    Sullivan, John T.; McGee, Thomas J.; Hoff, Raymond M.; Sumnicht, Grant; Twigg, Laurence

    2016-06-01

    Although characterizing the interactions of ozone throughout the entire troposphere are important for health and climate processes, there is a lack of routine measurements of vertical profiles within the United States. In order to monitor this lower ozone more effectively, the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center TROPospheric OZone DIfferential Absorption Lidar (GSFC TROPOZ DIAL) has been developed and validated within the Tropospheric Ozone Lidar Network (TOLNet). Two scientifically interesting ozone episodes are presented that were observed during the 2014 Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER AQ) campaign at Ft. Collins, Colorado. The first case study, occurring between 22-23 July 2014, indicates enhanced concentrations of ozone at Ft. Collins during nighttime hours, which was due to the complex recirculation of ozone within the foothills of the Rocky Mountain region. Although quantifying the ozone increase aloft during recirculation episodes has been historically difficult, results indicate that an increase of 20 - 30 ppbv of ozone at the Ft. Collins site has been attributed to this recirculation. The second case, occurring between Aug 4-8th 2014, characterizes a dynamical exchange of ozone between the stratosphere and the troposphere. This case, along with seasonal model parameters from previous years, is used to estimate the stratospheric contribution to the Rocky Mountain region. Results suggest that a large amount of stratospheric air is residing in the troposphere in the summertime near Ft. Collins, CO. The results also indicate that warmer tropopauses are correlated with an increase in stratospheric air below the tropopause in the Rocky Mountain Region.

  10. [Ozone exposure and asthma].

    PubMed

    Kleis, S; Louis, R; Bartsch, P

    2003-03-01

    Ozone is a pollutant the production of which depends on weather conditions and car engine combustion. Numerous epidemiological studies have indicated that high ozone levels correlated with morbidity in asthma. Experimental studies have shown that exposure of healthy subjects and asthmatics to ozone levels comparable to those measured in ambient air during hot summer days can generate respiratory symptoms, neutrophilic airways inflammation and lung function impairment. Lung function changes following ozone exposure are more pronounced in asthmatics and are dependent on the duration and intensity of exposure, a previous exposure and the nutritional status of the subjects. The airway epithelial cell layer is likely to play a pivotal role in initiating the inflammatory process following ozone exposure. Control of ambient air ozone levels must be a target for public health authorities.

  11. Biological effects of ozone

    SciTech Connect

    Lippmann, M. )

    1989-09-01

    Tropospheric ozone, a classic anthropogenic air pollutant, is going to remain a troublesome byproduct of contemporary civilization for many decades. We have known for some time that the hydrocarbons and nitrogen oxides from motor vehicles, together with actinic radiation, account for local and regional photochemistry leading to prolonged afternoon ozone peaks. We also now know that agricultural burning and intensive animal husbandry elevate regional and mesoscale concentrations of ozone and its precursors, and that remote background levels of ozone have been rising steadily throughout this century. The changes we will have to make in emission controls to appreciably reduce current tropospheric ozone levels will have profound effects on our transportation systems, consumer products, and lifestyles. As a society, we will have to make difficult choices about the levels of ozone-associated health, welfare, and natural system damage we will tolerate, or conversely, how much we are willing to pay for controls which can minimize the damage.

  12. Ozone therapy in periodontics

    PubMed Central

    Gupta, G; Mansi, B

    2012-01-01

    Gingival and Periodontal diseases represent a major concern both in dentistry and medicine. The majority of the contributing factors and causes in the etiology of these diseases are reduced or treated with ozone in all its application forms (gas, water, oil). The beneficial biological effects of ozone, its anti-microbial activity, oxidation of bio-molecules precursors and microbial toxins implicated in periodontal diseases and its healing and tissue regeneration properties, make the use of ozone well indicated in all stages of gingival and periodontal diseases. The primary objective of this article is to provide a general review about the clinical applications of ozone in periodontics. The secondary objective is to summarize the available in vitro and in vivo studies in Periodontics in which ozone has been used. This objective would be of importance to future researchers in terms of what has been tried and what the potentials are for the clinical application of ozone in Periodontics. PMID:22574088

  13. Spatial patterns of tropospheric ozone in the Mount Rainier region of the Cascade Mountains, USA

    USGS Publications Warehouse

    Brace, S.; Peterson, D.L.

    1998-01-01

    Few data exist on tropospheric ozone concentrations in rural and wildland areas of western Washington, U.S.A. We measured tropospheric ozone in Mount Rainier National Park and the Puget Sound region of Washington using electronic analyzers and passive samplers during the summers of 1994 and 1995. Electronic analyzers recorded hourly ozone concentrations from five locations between Seattle and Mount Rainier. Ozone concentrations generally increased with distance from Seattle, with maximum hourly concentrations recorded at Enumclaw (319 m elevation, 50 km SE of Seattle). Paradise (1650 m elevation, 100 km SE of Seattle) had the highest monthly mean concentration of all sites measured with analyzers. Diurnal patterns on high-ozone days indicate that concentrations at Paradise remain near 60 ppbv throughout the day, whereas ozone concentrations closer to Seattle had higher peaks during the afternoon but dropped to near zero at night. Passive ozone samplers were used to measure weekly average ozone exposures in four river drainages within Mount Rainier National Park, across an elevation gradient (420 a??2100 m). In most drainages, ozone levels increased with elevation, with highest average weekly ozone exposure (47 ppbv) recorded at 2100 m. Ozone concentrations are significantly higher in the western portion of the park, indicating that ozone exposure varies considerably over short distances. These data provide a reference point for air quality in western Washington and indicate that intensive sampling is necessary to quantify spatial patterns of tropospheric ozone in mountainous regions.

  14. The Antarctic ozone hole

    NASA Technical Reports Server (NTRS)

    Stolarski, Richard S.

    1988-01-01

    Processes that may be responsible for the thinning in the ozone layer above the South Pole are described. The chlorine catalytic cycle which destroys ozone is described, as are the major types of reactions that are believed to interfere with this cycle by forming chlorine reservoirs. The suspected contributions of polar stratospheric clouds to these processes are examined. Finally, the possibility that the ozone hole may be due more to a shift in atmospheric dynamics than to chemical destruction is addressed.

  15. Changes in stratospheric ozone.

    PubMed

    Cicerone, R J

    1987-07-01

    The ozone layer in the upper atmosphere is a natural feature of the earth's environment. It performs several important functions, including shielding the earth from damaging solar ultraviolet radiation. Far from being static, ozone concentrations rise and fall under the forces of photochemical production, catalytic chemical destruction, and fluid dynamical transport. Human activities are projected to deplete substantially stratospheric ozone through anthropogenic increases in the global concentrations of key atmospheric chemicals. Human-induced perturbations may be occurring already.

  16. Surface ozone measurements using differential absorption lidar

    NASA Astrophysics Data System (ADS)

    Jain, Sohan L.; Arya, B. C.; Ghude, Sachin D.; Arora, Arun K.; Sinha, Randhir K.

    2005-01-01

    Human activities have been influencing the global atmosphere since the beginning of the industrial era, causing shifts from its natural state. The measurements have shown that tropospheric ozone is increasing gradually due to anthropogenic activities. Surface ozone is a secondary pollutant, its concentration in lower troposphere depends upon its precursors (CO, CH4, non methane hydrocarbons, NOx) as well as weather and transport phenomenon. The surface ozone exceeding the ambient air quality standard is health hazard to human being, animal and vegetation. The regular information of its concentrations on ground levels is needed for setting ambient air quality objectives and understanding photo chemical air pollution in urban areas. A Differential Absorption Lidar (DIAL) using a tunable CO2 laser has been designed and developed at National Physical Laboratory, New Delhi, to monitor water vapour, surface ozone, ammonia, ethylene etc. Some times ethylene and surface ozone was found to be more than 40 ppb and 140 ppb respectively which is a health hazard. Seasonal variation in ozone concentrations shows maximum in the months of summer and autumn and minimum in monsoon and winter months. In present communication salient features of experimental set up and results obtained will be presented in detail.

  17. Adsorption air cleaning from ozone.

    PubMed

    Baltrenas, Pranas; Paliulis, Dainius; Vasarevicius, Saulius; Simaitis, Ramutis

    2003-01-01

    Not much has been written about air cleaning from ozone. The aim of this paper was to demonstrate the possibility of adsorption air cleaning from ozone. The second aim was to investigate the dependence of the efficiency of ozone removal from the air on the height of the adsorber layer and on concentrations of ozone, and to obtain empirical formulas for calculating the efficiency of ozone treatment. Equipment for air cleaning from ozone and nitrogen and sulphur dioxides is suggested.

  18. The 1989 Antarctic ozone hole as observed by TOMS (Total Ozone Mapping Spectrometer)

    SciTech Connect

    Stolarski, R.S.; Schoeberl, M.R.; McPeters, R.D.; Krueger, A.J. ); Newman, P.A. )

    1990-08-01

    In 1989 the Total Ozone Mapping Spectrometer (TOMS) aboard the Nimbus 7 satellite observed the springtime decrease in Antarctic total ozone for the 11th consecutive year. The 1989 minimum values of total ozone measured by TOMS declined throughout the month of September a6t a rate nearly identical to 1987. The National Meteorological Center analysis of lower stratospheric temperatures in August and September 1989 also showed conditions similar to those observed in 1987. A minimum in total ozone of 111 DU was reached on October 7, 1989. Within uncertainties this is the same as previously observed minimum on October 5, 1987. The area of the ozone hole as defined by the 220 DU contour grew rapidly during early September. It reached a mid-September peak of 7.5% of the southern hemisphere or 19 million square kilometers, essentially the same as observed in 1987. From mid October through November 1989, minimum polar total ozone values increased and the are within the 220 DU contour decreased more rapidly than during the comparable period of 1987. The more rapid erosion of the 1989 ozone hole resulted from strong wave number one perturbations of the vortex dynamics in late October.

  19. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  20. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  1. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  2. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  3. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  4. 40 CFR 51.902 - Which classification and nonattainment area planning provisions of the CAA shall apply to areas...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.902 Which classification and... with a 1-hour ozone design value equal to or greater than 0.121 ppm at the time the Administrator signs...) Covered under subpart 1 (CAA). An area designated nonattainment for the 8-hour ozone NAAQS with a...

  5. 40 CFR 51.902 - Which classification and nonattainment area planning provisions of the CAA shall apply to areas...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.902 Which classification and... with a 1-hour ozone design value equal to or greater than 0.121 ppm at the time the Administrator signs...) Covered under subpart 1 (CAA). An area designated nonattainment for the 8-hour ozone NAAQS with a...

  6. Nimbus 7 solar backscatter ultraviolet (SBUV) ozone products user's guide

    NASA Technical Reports Server (NTRS)

    Fleig, Albert J.; Mcpeters, R. D.; Bhartia, P. K.; Schlesinger, Barry M.; Cebula, Richard P.; Klenk, K. F.; Taylor, Steven L.; Heath, Donald F.

    1990-01-01

    Three ozone tape products from the Solar Backscatter Ultraviolet (SBUV) experiment aboard Nimbus 7 were archived at the National Space Science Data Center. The experiment measures the fraction of incoming radiation backscattered by the Earth's atmosphere at 12 wavelengths. In-flight measurements were used to monitor changes in the instrument sensitivity. Total column ozone is derived by comparing the measurements with calculations of what would be measured for different total ozone amounts. The altitude distribution is retrieved using an optimum statistical technique for the inversion. The estimated initial error in the absolute scale for total ozone is 2 percent, with a 3 percent drift over 8 years. The profile error depends on latitude and height, smallest at 3 to 10 mbar; the drift increases with increasing altitude. Three tape products are described. The High Density SBUV (HDSBUV) tape contains the final derived products - the total ozone and the vertical ozone profile - as well as much detailed diagnostic information generated during the retrieval process. The Compressed Ozone (CPOZ) tape contains only that subset of HDSBUV information, including total ozone and ozone profiles, considered most useful for scientific studies. The Zonal Means Tape (ZMT) contains daily, weekly, monthly and quarterly averages of the derived quantities over 10 deg latitude zones.

  7. The Antarctic Ozone Hole.

    ERIC Educational Resources Information Center

    Stolarski, Richard S.

    1988-01-01

    Discusses the Airborne Antarctic Ozone Experiment (1987) and the findings of the British Antarctic Survey (1985). Proposes two theories for the appearance of the hole in the ozone layer over Antarctica which appears each spring; air pollution and natural atmospheric shifts. Illustrates the mechanics of both. Supports worldwide chlorofluorocarbon…

  8. Ozone and temperature trends

    NASA Technical Reports Server (NTRS)

    Stolarski, Richard S.; Fioletov, Vitali; Bishop, Lane; Godin, Sophie; Bojkov, Rumen D.; Kirchhoff, Volker; Chanin, Marie-Lise; Zawodny, Joseph M.; Zerefos, Christos S.; Chu, William

    1991-01-01

    An update of the extensive reviews of the state of knowledge of measured ozone trends published in the Report of the International Ozone Trends Panel is presented. The update contains a review of progress since these reports, including reviewing of the ozone records, in most cases through March 1991. Also included are some new, unpublished reanalyses of these records including a complete reevaluation of 29 stations located in the former Soviet Union. The major new advance in knowledge of the measured ozone trend is the existence of independently calibrated satellite data records from the Total Ozone Mapping Spectrometer (TOMS) and Stratospheric Aerosol and Gas Experiment (SAG) instruments. These confirm many of the findings, originally derived from the Dobson record, concerning northern mid-latitude changes in ozone. We now have results from several instruments, whereas the previously reported changes were dependent on the calibration of a single instrument. This update will compare the ozone records from many different instruments to determine whether or not they provide a consistent picture of the ozone change that has occurred in the atmosphere. The update also briefly considers the problem of stratospheric temperature change. As in previous reports, this problem received significantly less attention, and the report is not nearly as complete. This area needs more attention in the future.

  9. Saving Our Ozone Shield.

    ERIC Educational Resources Information Center

    Lacoste, Beatrice

    1992-01-01

    Discusses the introduction and continued use of chlorofluorocarbons (CFCs) as related to stratospheric ozone depletion. Presents the characteristics of CFCs conducive to the chemical reaction with ozone, the history of CFC use and detection of related environmental problems, health hazards, and alternatives to CFC use. (MCO)

  10. Polar Ozone Workshop. Abstracts

    NASA Technical Reports Server (NTRS)

    Aikin, Arthur C.

    1988-01-01

    Results of the proceedings of the Polar Ozone Workshop held in Snowmass, CO, on May 9 to 13, 1988 are given. Topics covered include ozone depletion, ozonometry, polar meteorology, polar stratospheric clouds, remote sensing of trace gases, atmospheric chemistry and dynamical simulations.

  11. Ozone NAAQS Review: Risk/Exposure Assessment

    EPA Science Inventory

    Ozone is one of the six major air pollutants for which EPA has issued air quality criteria and established national ambient air quality standards (NAAQS) based on those criteria. The Clear Air Act (CAA) requires EPA to periodically review and revise, as appropriate, existing air ...

  12. Role of Methane in Antarctic Stratospheric Ozone Recovery

    NASA Astrophysics Data System (ADS)

    Calvo, Natalia; Kinnison, Douglas E.; Marsh, Daniel R.; Garcia, Rolando R.; Palmeiro, Froila

    2014-05-01

    Observational and modeling studies have shown the impact of changes in Antarctic stratospheric ozone on tropospheric climate in austral spring and summer. In the future, effects of increasing greenhouse gases and ozone depleting substances oppose each other. Projections show potential impact of ozone recovery on precipitation, carbon uptake in the Southern Hemisphere ocean, Antarctic ice sheets and Southern Hemisphere sea ice. In order to quantify properly the tropospheric impacts of ozone recovery, future Antarctic ozone changes in the upper troposphere lower stratosphere region and the role (if any) of increasing greenhouse gases in ozone recovery need to be evaluated. To do so, we use the National Center for Atmospheric Research's Community Earth System Model, CESM, with the high-top version of the atmospheric component, CESM(WACCM), which is a fully coupled chemistry climate model. Three climate change scenarios (RCP2.6, RCP4.5 and RCP8.5) of 3 simulations each from 2005 to 2065 are analyzed. In scenario RCP2.6, the largest ozone recovery is simulated in October and November at 50hPa and it is followed by the largest response in temperature in November and December at 70hPa. While the response in RCP4.5 in ozone and temperature is almost identical to that in RCP2.6 in the upper troposphere and lower stratosphere region, scenario RCP8.5 shows significantly stronger ozone recovery and warming than the other two scenarios, particularly in November and December at 70hPa in ozone and 100hPa in temperature. We show that this is due to larger amounts of methane in RCP8.5 compared to the other two scenarios, which reduces catalytic ozone loss locally. Differences across scenarios in advection of ozone from the source region in the tropical stratosphere do not play a significant role.

  13. Observing trends in total ozone and extreme ozone events

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2014-05-01

    The ozone layer in the stratosphere has been recovering since the 1989 Montreal Protocol reduced the use of ozone-destroying chlorofluorocarbons. Fitzka et al. observed trends in total ozone levels and the vertical distribution of ozone at Hoher Sonnblick, a mountain in Austria, from 1994 to 2011.

  14. Ozone in equatorial latitudes

    NASA Astrophysics Data System (ADS)

    Martini, L.; Zimmermann, G.; Trinkkeller, B.

    The presence of ozone in the atmosphere protects the biosphere against harmful solar UV radiation. The ozone distribution in the atmosphere is maintained on the basis of a complex system of reactions. The amount of atmospheric ozone might be reduced as a consequence of human activities. Such reduction in the atmospheric ozone could affect climate and biological processes on earth. As a part of plans for a further enhancement of the global surveillance of the atmospheric ozone layer, a series of radiation experiments concerning the quartz-ultraviolet region were conducted as a joint project of the German Democratic Republic and the USSR. The experiments had the objective to measure the radiative flux of the solar UV radiation and to determine absorption and dispersion of the radiation in the upper atmosphere. The investigation included the launching of 12 rockets from a research vessel in the Indian Ocean near the equator and 34 balloon flights.

  15. Accord on the deepening problem of ozone depletion

    SciTech Connect

    Not Available

    1987-10-01

    In September representatives of 24 or 46 negotiating nations signed a treaty designed to freeze and eventually cut the world's consumption of chlorofluorocarbons (CFCs), a class of chemicals implicated in the depletion of the ozone layer. The treaty also calls for a freeze on halons, a class of similar ozone-depleting chemicals used primarily in fire extinguishers. Yet, even under the scenario prescribed by the treaty, a 2% loss of ozone by the mid-21st century is still forecast. At the same time as the treaty signing, scientists organized by the US National Aeronautics and Space Administration were flying airplanes into the upper reaches of the ozone layer over Antarctica. They found the ozone hole, which appears each spring, this year to be the largest yet - reflecting a 55% decrease in ozone concentration from 1979. High levels of chlorine were recorded along with low levels of ozone. The scientists also found that ozone levels could drop dramatically in the course of one day, indicating that the meteorological dynamics of the South Pole could be contributing to the loss caused by the chlorine. In the US there are signs of a movement to eliminate the use of CFCs in manufacturing the plastic foams that hold fast-food hamburgers.

  16. 40 CFR 52.522 - Approval status.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... national standards under section 110 of the Clean Air Act. Furthermore, the Administrator finds that the...), and 110(a)(2)(J) for the 2008 8-hour Ozone National Ambient Air Quality Standards related to...), 110(a)(2)(D)(i)(II), and 110(a)(2)(J) for the 2008 8-hour Ozone National Ambient Air Quality...

  17. 78 FR 3867 - Approval and Promulgation of Implementation Plans; Kentucky; 110(a)(1) and (2) Infrastructure...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-17

    ...) Infrastructure Requirements for the 2008 8-Hour Ozone National Ambient Air Quality Standards AGENCY... Particulate Matter National Ambient Air Quality Standards'' in the section entitled, ``Scope of Infrastructure... Clean Air Act (CAA or Act) requirements for the 2008 8-hour ozone national ambient air quality...

  18. 40 CFR 51.900 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hour NAAQS means the 1-hour ozone national ambient air quality standards codified at 40 CFR 50.9. (b) 8-hour NAAQS means the 8-hour ozone national ambient air quality standards codified at 40 CFR 50.10. (c... National Ambient Air Quality Standard § 51.900 Definitions. The following definitions apply for purposes...

  19. The Transition of Atmospheric Infrared Sounder Total Ozone Products to Operations

    NASA Technical Reports Server (NTRS)

    Berndt, E. B.; Zavodsky, B. T.; Jedlovec, G. J.

    2014-01-01

    The National Aeronautics and Space Administration Short-term Prediction Research and Transition Center (NASA SPoRT) has transitioned a total column ozone product from the Atmospheric Infrared Sounder (AIRS) retrievals to the Weather Prediction Center and Ocean Prediction Center. The total column ozone product is used to diagnose regions of warm, dry, ozone-rich, stratospheric air capable of descending to the surface to create high-impact non-convective winds. Over the past year, forecasters have analyzed the Red, Green, Blue (RGB) Air Mass imagery in conjunction with the AIRS total column ozone to aid high wind forecasts. One of the limitations of the total ozone product is that it is difficult for forecasters to determine whether elevated ozone concentrations are related to stratospheric air or climatologically high values of ozone in certain regions. During the summer of 2013, SPoRT created an AIRS ozone anomaly product which calculates the percent of normal ozone based on a global stratospheric ozone mean climatology. With the knowledge that ozone values 125 percent of normal and greater typically represent stratospheric air; the anomaly product can be used with the total column ozone product to confirm regions of stratospheric air. This paper describes the generation of these products along with forecaster feedback concerning the use of the AIRS ozone products in conjunction with the RGB Air Mass product to access the utility and transition of the products.

  20. Sensitivity analysis of ground level ozone in India using WRF-CMAQ models

    NASA Astrophysics Data System (ADS)

    Sharma, Sumit; Chatani, Satoru; Mahtta, Richa; Goel, Anju; Kumar, Atul

    2016-04-01

    Ground level ozone is emerging as a pollutant of concern in India. Limited surface monitoring data reveals that ozone concentrations are well above the prescribed national standards. This study aims to simulate the regional and urban scale ozone concentrations in India using WRF-CMAQ models. Sector-specific emission inventories are prepared for the ozone precursor species at a finer resolution (36 × 36 km2) than used in previous studies. Meteorological fields developed using the WRF model are fed into the CMAQ model along with the precursor emissions to simulate ozone concentrations at a regional scale. The model is validated using observed ozone dataset. Sensitivity analysis is carried out to understand the effect of different precursor species and sources on prevailing ozone concentrations in India. The results show that NOx sensitive conditions prevail in India and control of NOx will result in more reduction in ozone than VOCs. However, further growth in the transport and power sector and decreasing VOC emissions from the residential sector may increase the sensitivity of VOCs towards ozone in the future. At the urban scale, presence of high NOx emissions form VOC limited conditions and reduction of NOx results in increase in ozone concentrations. However, this will help in improving regional scale ozone pollution in the downwind regions. A non-linear response has been observed while assessing the sectoral sensitivities of ozone formation. Transport sector is found to have the maximum potential for reducing ozone concentrations in India.

  1. The Hole in the Ozone Layer.

    ERIC Educational Resources Information Center

    Hamers, Jeanne S.; Jacob, Anthony T.

    This document contains information on the hole in the ozone layer. Topics discussed include properties of ozone, ozone in the atmosphere, chlorofluorocarbons, stratospheric ozone depletion, effects of ozone depletion on life, regulation of substances that deplete the ozone layer, alternatives to CFCs and Halons, and the future of the ozone layer.…

  2. Fundamentals of ISCO Using Ozone

    EPA Science Inventory

    In situ chemical oxidation (ISCO) using ozone involves the introduction of ozone gas (O3) into the subsurface to degrade organic contaminants of concern. Ozone is tri-molecular oxygen (O2) that is a gas under atmospheric conditions and is a strong oxidant. Ozone may react with ...

  3. The Two Faces of Ozone.

    ERIC Educational Resources Information Center

    Monastersky, Richard

    1989-01-01

    Provides answers to questions regarding the ozone problem: (1) nature of ozone in the troposphere and stratosphere; (2) possibility of sending the excess ozone at ground level to the stratosphere; (3) possibility of producing pure ozone and carrying it to the stratosphere; and (4) banning chlorofluorocarbons. (YP)

  4. Comparison of SBUV and SAGE II ozone profiles: Implications for ozone trends

    NASA Technical Reports Server (NTRS)

    Mcpeters, R. D.; Miles, T.; Flynn, L. E.; Wellemeyer, C. G.; Zawodny, J. M.

    1994-01-01

    Solar backscattered ultraviolet (SBUV) ozone profiles have been compared with Stratospheric Aerosol and Gas Experiment (SAGE) II profiles over the period October 1984 through June 1990, when data are available from both instruments. SBUV measurements were selected to closely match the SAGE II latitude/longitude measurement pattern. There are significant differences between the SAGE II sunrise and the sunset zonal mean ozone profiles in the equatorial zone, particularly in the upper stratosphere, that may be connected with extreme SAGE II solar azimuth angles for tropical sunrise measurements. Calculation of the average sunset bias between SBUV and SAGE II ozone profiles shows that allowing for diurnal variation in Umkehr layer 10, SBUV and SAGE II agree to within +/- 5% for the entire stratosphere in the northern midlatitude zone. The worst agreement is seen at southern midlatitudes near the ozone peak (disagreements of +/- 10%), apparently the result of the SBUV ozone profile peaking at a lower altitude than SAGE. The integrated ozone columns (cumulative above 15 km) agree very well, to within +/- 2.3% in all zones for both sunset and sunrise measurements. A comparison of the time dependence of SBUV and SAGE II shows that there was less than +/- 5% relative drift over the 5.5 years for all altitudes except below 25 km, where the SBUV vertical resolution is poor. The best agreement with SAGE is seen in the integrated column ozone (cumulative above 15 km), where SAGE II has a 1% negative trend relative to SBUV over the comparison period. There is a persistent disagreement of the two instruments in Umkehr layers 9 and 10 of +/- 4% over the 5.5-year comparison period. In the equatorial zone this disagreement may be caused in part by a large positive trend (0.8 K per year) in the National Meteorologica Center temperatures used to convert the SAGE II measurement of ozone density versus altitude to a pressure scale for comparison with SBUV. In the middle stratosphere (30

  5. Ozone distribution in remote ecologically vulnerable terrain of the southern Sierra Nevada, CA.

    PubMed

    Panek, Jeanne; Saah, David; Esperanza, Annie; Bytnerowicz, Andrzej; Fraczek, Witold; Cisneros, Ricardo

    2013-11-01

    Ozone concentration spatial patterns remain largely uncharacterized across the extensive wilderness areas of the Sierra Nevada, CA, despite being downwind of major pollution sources. These natural areas, including four national parks and four national forests, contain forest species that are susceptible to ozone injury. Forests stressed by ozone are also more vulnerable to other agents of mortality, including insects, pathogens, climate change, and ultimately fire. Here we analyze three years of passive ozone monitor data from the southern Sierra Nevada and interpolate landscape-scale spatial and temporal patterns during the summer-through-fall high ozone concentration period. Segmentation analysis revealed three types of ozone exposure sub-regions: high, low, and variable. Consistently high ozone exposure regions are expected to be most vulnerable to forest mortality. One high exposure sub-region has been documented elsewhere as being further vulnerable to increased drought and fire potential. Identifying such hot-spots of forest vulnerability has utility for prioritizing management.

  6. History of Ozone Research: From Schonbein to the Present

    NASA Technical Reports Server (NTRS)

    Stolarski, Richard S.

    1999-01-01

    national regulations to limit its potential for causing health problems and corrosive effects on materials. A lot is known about ozone but many new questions are still being developed.

  7. Global tropospheric ozone investigations

    NASA Technical Reports Server (NTRS)

    Browell, Edward V.

    1998-01-01

    Ozone (O3) is one of the most important trace gases in the troposphere, and it is responsible for influencing many critical chemical and radiative processes. Ozone contributes to the formation of the hydroxyl radical (OH), which is central to most chemical reactions in the lower atmosphere, and it absorbs UV, visible, and infrared radiation which affects the energy budget and atmospheric temperatures. In addition, O3 can be used as a tracer of atmospheric pollution and stratosphere troposphere exchange. At elevated concentrations, O3 can also produce detrimental biological and human health effects. The US National Research Council (NRC) Board on Sustainable Development reviewed the US Global Change Research Program (USGCRP) [NRC, 1995], and it identified tropospheric chemistry as one of the high priority areas for the USGCRP in the next decade. The NRC identified the following specific challenges in tropospheric chemistry. Although we understand the reason for the high levels of 03 over several regions of the world, we need to better establish the distribution of O3 in the troposphere in order to document and understand the changes in the abundance of global tropospheric O3. This information is needed to quantify the contribution of O3 to the Earth' s radiative balance and to understand potential impacts on the health of the biosphere. Having recognized the importance of particles in the chemistry of the stratosphere, we must determine how aerosols and clouds affect the chemical processes in the troposphere. This understanding is essential to predict the chemical composition of the atmosphere and to assess the resulting forcing effects in the climate system. We must determine if the self-cleansing chemistry of the atmosphere is changing as a result of human activities. This information is required to predict the rate at which pollutants are removed from the atmosphere. Over nearly two decades, airborne Differential Absorption Lidar (DIAL) systems have been used in

  8. Who is more affected by ozone pollution? A systematic review and meta-analysis.

    PubMed

    Bell, Michelle L; Zanobetti, Antonella; Dominici, Francesca

    2014-07-01

    Ozone is associated with adverse health; however, less is known about vulnerable/sensitive populations, which we refer to as sensitive populations. We systematically reviewed epidemiologic evidence (1988-2013) regarding sensitivity to mortality or hospital admission from short-term ozone exposure. We performed meta-analysis for overall associations by age and sex; assessed publication bias; and qualitatively assessed sensitivity to socioeconomic indicators, race/ethnicity, and air conditioning. The search identified 2,091 unique papers, with 167 meeting inclusion criteria (73 on mortality and 96 on hospitalizations and emergency department visits, including 2 examining both mortality and hospitalizations). The strongest evidence for ozone sensitivity was for age. Per 10-parts per billion increase in daily 8-hour ozone concentration, mortality risk for younger persons, at 0.60% (95% confidence interval (CI): 0.40, 0.80), was statistically lower than that for older persons, at 1.27% (95% CI: 0.76, 1.78). Findings adjusted for publication bias were similar. Limited/suggestive evidence was found for higher associations among women; mortality risks were 0.39% (95% CI: -0.22, 1.00) higher than those for men. We identified strong evidence for higher associations with unemployment or lower occupational status and weak evidence of sensitivity for racial/ethnic minorities and persons with low education, in poverty, or without central air conditioning. Findings show that some populations, especially the elderly, are particularly sensitive to short-term ozone exposure. PMID:24872350

  9. Surface ozone background in the United States: Canadian and Mexican pollution influences

    NASA Astrophysics Data System (ADS)

    Wang, Huiqun; Jacob, Daniel J.; Le Sager, Philippe; Streets, David G.; Park, Rokjin J.; Gilliland, Alice B.; van Donkelaar, A.

    We use a global chemical transport model (GEOS-Chem) with 1° × 1° horizontal resolution to quantify the effects of anthropogenic emissions from Canada, Mexico, and outside North America on daily maximum 8-hour average ozone concentrations in US surface air. Simulations for summer 2001 indicate mean North American and US background concentrations of 26 ± 8 ppb and 30 ± 8 ppb, as obtained by eliminating anthropogenic emissions in North America vs. in the US only. The US background never exceeds 60 ppb in the model. The Canadian and Mexican pollution enhancement averages 3 ± 4 ppb in the US in summer but can be occasionally much higher in downwind regions of the northeast and southwest, peaking at 33 ppb in upstate New York (on a day with 75 ppb total ozone) and 18 ppb in southern California (on a day with 68 ppb total ozone). The model is successful in reproducing the observed variability of ozone in these regions, including the occurrence and magnitude of high-ozone episodes influenced by transboundary pollution. We find that exceedances of the 75 ppb US air quality standard in eastern Michigan, western New York, New Jersey, and southern California are often associated with Canadian and Mexican pollution enhancements in excess of 10 ppb. Sensitivity simulations with 2020 emission projections suggest that Canadian pollution influence in the Northeast US will become comparable in magnitude to that from domestic power plants.

  10. Ozone - plant surface reactions an important ozone loss term?

    NASA Astrophysics Data System (ADS)

    Hansel, Armin; Jud, Werner; Fischer, Lukas; Canaval, Eva; Wohlfahrt, Georg; Tissier, Alain

    2015-04-01

    Elevated tropospheric ozone concentrations are considered a toxic threat to plants responsible for global crop losses with associated economic costs of several billions dollar per year. Plant injuries have been related to the uptake of ozone through stomatal pores and oxidative effects damaging the internal leaf tissue. But a striking question remains: How much ozone enters the plant through open stomata and how much ozone is lost by chemical reactions at the plant surface? Until now surface losses are estimated from measured total ozone deposition fluxes and calculated stomatal conductance values. While stomatal conductance of CO2 and H2O is well understood and extensively used in describing plant atmosphere gas exchange, stomatal conductance of ozone is not well known. Here we use different Nicotiana tabacum varieties and find that surface reactions of ozone with diterpenoids synthesized by glandular trichomes reduce ozone flux through open stomata. Our measurements reveal that fast ozone loss at the plant surface is accompanied with prompt release of oxygenated volatile compounds. In the ozone fumigation experiments of different Nicotiana tabacum varieties the release of specific volatile oxy-VOCs allowed to identify the semi volatile precursor compounds at the plant surface. Ozone fumigation experiments with Norway spruce (Picea abies) and Scots Pine (Pinus sylvestris), two common species in the Northern Hemisphere, show also a significant ozone loss at the plant surface for Picea abies. Fluid dynamic calculations of ozone transport in the diffusive leaf boundary layer reveal a vertical but no horizontal ozone gradient thus reducing ozone fluxes through the pores in case of efficient ozone scavenging plant surfaces. We explain this efficient ozone protection mechanism by the porous surface architecture of plants in combination with unsaturated semi-volatile compounds deposited at the plant surface. These results show that unsaturated semi-volatile compounds at

  11. Ozone Profiles and Tropospheric Ozone from Global Ozone Monitoring Experiment

    NASA Technical Reports Server (NTRS)

    Liu, X.; Chance, K.; Sioris, C. E.; Sparr, R. J. D.; Kuregm, T. P.; Martin, R. V.; Newchurch, M. J.; Bhartia, P. K.

    2003-01-01

    Ozone profiles are derived from backscattered radiances in the ultraviolet spectra (290-340 nm) measured by the nadir-viewing Global Ozone Monitoring Experiment using optimal estimation. Tropospheric O3 is directly retrieved with the tropopause as one of the retrieval levels. To optimize the retrieval and improve the fitting precision needed for tropospheric O3, we perform extensive wavelength and radiometric calibrations and improve forward model inputs. Retrieved O3 profiles and tropospheric O3 agree well with coincident ozonesonde measurements, and the integrated total O3 agrees very well with Earth Probe TOMS and Dobson/Brewer total O3. The global distribution of tropospheric O3 clearly shows the influences of biomass burning, convection, and air pollution, and is generally consistent with our current understanding.

  12. Polar Ozone Losses

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.; Bhartia, P. K. (Technical Monitor)

    2001-01-01

    Since the discovery of the Antarctic ozone hole, a great deal of attention has been focused on the polar regions to both identify the chemistry and physics of the large losses, and to provide an understanding of the future of polar ozone. In this review talk, I will discuss the secular trends of ozone in both the Antarctic and Arctic regions, and I will review some of the principal research results of the last few years. In particular, I will emphasize some of the results from the SOLVE-THESEO 2000 campaign that occurred over the course of the winter of 1999-2000.

  13. Arctic ozone loss

    SciTech Connect

    Zurer, P.S.

    1989-03-06

    Scientists have returned from the first comprehensive probe of the Arctic stratosphere with unexpectedly dire results: The winter atmosphere in the north polar region is loaded with the same destructive chlorine compounds that cause the Antarctic ozone hole. Atmospheric researchers who only a few weeks ago were comforted by the thought that the warmer Northern Hemisphere is strongly protected from the processes that lead to massive losses of ozone during spring in Antarctica now see very little standing in the way of an Arctic ozone hole.

  14. The Impact of Meteorology on Ozone Levels in the Lake Tahoe Basin

    NASA Astrophysics Data System (ADS)

    Theiss, Sandra

    The Lake Tahoe Basin is located on the California-Nevada border and occasionally experiences elevated levels of ozone exceeding the 70 ppb California Air Resources Board (CARB) ambient air quality standard (8-hour average). Previous studies indicate that both the local generation of ozone in the Basin and long-range transport from out-of-Basin sources are important in contributing to ozone exceedances, but little is known about the impact of meteorology on the distribution of ozone source regions. In order to develop a better understanding of the factors affecting ozone levels and sources in the Lake Tahoe Basin, this study combines observational data from a 2010 and 2012 summer field campaigns, HYSPLIT back trajectories, and WRF model output to examine the meteorological influences of ozone transport in the topographically complex Lake Tahoe Basin. Findings from the field work portions of this study include enhanced background ozone levels at higher elevations, the local circulation pattern of lake breezes occurring at Lake level sites, and an indication that ozone precursors are coming off the Lake. Our analysis also showed that if transport of ozone does occur, it is more likely to come from the San Joaquin Valley to the south rather than originate in the large cities to the west, such as Sacramento and San Francisco. Analysis of modeled PBL schemes as compared with observational data showed that the ACM2 PBL scheme best represented the geographical domain. The ACM2 PBL scheme was then used to show wind circulation patterns in the Lake Tahoe Basin and concluded that there is decent vertical mixing over the Basin and no indication of ozone transport from the west however some indication of transport from the east. Overall this study concludes that transport from the west is less significant than transport from the south and east, and that transport only influences ozone values at higher elevations. Within the Basin itself (at lower elevations), local factors

  15. Ozone Correlative Measurements Workshop

    NASA Technical Reports Server (NTRS)

    Hilsenrath, E. (Editor)

    1985-01-01

    A study was conducted to determine the necessary parameters for the correlation of data on Earth ozone. Topics considered were: (1) measurement accuracy; (2) equipment considerations (SBUV); and (3) ground based measurements to support satellite data.

  16. Ozone Therapy in Dentistry

    PubMed Central

    Domb, William C

    2014-01-01

    Summary The 21st century dental practice is quite dynamic. New treatment protocols and new materials are being developed at a rapid pace. Ozone dental therapy falls into the category of new treatment protocols in dentistry, yet ozone is not new at all. Ozone therapy is already a major treatment modality in Europe, South America and a number of other countries. What is provided here will not be an exhaustive scientific treatise so much as a brief general introduction into what dentists are now doing with ozone therapies and the numerous oral/systemic links that make this subject so important for physicians so that, ultimately, they may serve their patients more effectively and productively. PMID:25363268

  17. 40 CFR 51.900 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... this subpart. Any term not defined herein shall have the meaning as defined in 40 CFR 51.100. (a) 1-hour NAAQS means the 1-hour ozone national ambient air quality standards codified at 40 CFR 50.9. (b) 8-hour NAAQS means the 8-hour ozone national ambient air quality standards codified at 40 CFR 50.10....

  18. 40 CFR 51.900 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... this subpart. Any term not defined herein shall have the meaning as defined in 40 CFR 51.100. (a) 1-hour NAAQS means the 1-hour ozone national ambient air quality standards codified at 40 CFR 50.9. (b) 8-hour NAAQS means the 8-hour ozone national ambient air quality standards codified at 40 CFR 50.10....

  19. 40 CFR 51.900 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... this subpart. Any term not defined herein shall have the meaning as defined in 40 CFR 51.100. (a) 1-hour NAAQS means the 1-hour ozone national ambient air quality standards codified at 40 CFR 50.9. (b) 8-hour NAAQS means the 8-hour ozone national ambient air quality standards codified at 40 CFR 50.10....

  20. The Impact of Emission and Climate Change on Ozone in the United States under Representative Concentration Pathways (RCPs)

    SciTech Connect

    Gao, Yang; Fu, Joshua S.; Drake, John B.; Lamarque, J.-F.; Liu, Yang

    2013-09-27

    Dynamical downscaling was applied in this study to link the global climate-chemistry model Community Atmosphere Model (CAM-Chem) with the regional models: Weather Research and Forecasting (WRF) Model and Community Multi-scale Air Quality (CMAQ). Two Representative Concentration Pathway (RCP) scenarios (RCP 4.5 and RCP 8.5) were used to evaluate the climate impact on ozone concentrations in 2050s. Ozone concentrations in the lower-mid troposphere (surface to ~300 hPa), from mid- to high latitudes in the Northern Hemisphere (NH), show decreasing trends in RCP 4.5 between 2000s and 2050s, with the largest decrease of 4-10 ppbv occurring in the summer and the fall; and increasing trends (2-12 ppbv) in RCP 8.5 resulting from the increased methane emissions. In RCP 8.5, methane emissions increase by ~60% by the end of 2050s, accounting for more than 90% of ozone increases in summer and fall, and 60-80% in spring and winter. Under the RCP 4.5 scenario, in the summer when photochemical reactions are the most active, the large ozone precursor emissions reduction leads to the greatest decrease of downscaled surface ozone concentrations, ranging from 6 to 10 ppbv. However, a few major cities show ozone increases of 3 to 7 ppbv due to weakened NO titration. Under the RCP 8.5 scenario, in winter, downscaled ozone concentrations increase across nearly the entire continental US in winter, ranging from 3 to 10 ppbv due to increased methane emissions and enhanced stratosphere-troposphere exchange (STE). More intense heat waves are projected to occur by the end of 2050s in RCP 8.5, leading to more than 8 ppbv of the maximum daily 8-hour daily average (MDA8) ozone during the heat wave days than other days; this indicates the dramatic impact heat waves exert on high frequency ozone events.

  1. The Case of Ozone Depletion

    NASA Technical Reports Server (NTRS)

    Lambright, W. Henry

    2005-01-01

    While the National Aeronautics and Space Administration (NASA) is widely perceived as a space agency, since its inception NASA has had a mission dedicated to the home planet. Initially, this mission involved using space to better observe and predict weather and to enable worldwide communication. Meteorological and communication satellites showed the value of space for earthly endeavors in the 1960s. In 1972, NASA launched Landsat, and the era of earth-resource monitoring began. At the same time, in the late 1960s and early 1970s, the environmental movement swept throughout the United States and most industrialized countries. The first Earth Day event took place in 1970, and the government generally began to pay much more attention to issues of environmental quality. Mitigating pollution became an overriding objective for many agencies. NASA's existing mission to observe planet Earth was augmented in these years and directed more toward environmental quality. In the 1980s, NASA sought to plan and establish a new environmental effort that eventuated in the 1990s with the Earth Observing System (EOS). The Agency was able to make its initial mark via atmospheric monitoring, specifically ozone depletion. An important policy stimulus in many respects, ozone depletion spawned the Montreal Protocol of 1987 (the most significant international environmental treaty then in existence). It also was an issue critical to NASA's history that served as a bridge linking NASA's weather and land-resource satellites to NASA s concern for the global changes affecting the home planet. Significantly, as a global environmental problem, ozone depletion underscored the importance of NASA's ability to observe Earth from space. Moreover, the NASA management team's ability to apply large-scale research efforts and mobilize the talents of other agencies and the private sector illuminated its role as a lead agency capable of crossing organizational boundaries as well as the science-policy divide.

  2. Treatment of Ammonia Nitrogen Wastewater in Low Concentration by Two-Stage Ozonization.

    PubMed

    Luo, Xianping; Yan, Qun; Wang, Chunying; Luo, Caigui; Zhou, Nana; Jian, Chensheng

    2015-09-23

    Ammonia nitrogen wastewater (about 100 mg/L) was treated by two-stage ozone oxidation method. The effects of ozone flow rate and initial pH on ammonia removal were studied, and the mechanism of ammonia nitrogen removal by ozone oxidation was discussed. After the primary stage of ozone oxidation, the ammonia removal efficiency reached 59.32% and pH decreased to 6.63 under conditions of 1 L/min ozone flow rate and initial pH 11. Then, the removal efficiency could be over 85% (the left ammonia concentration was lower than 15 mg/L) after the second stage, which means the wastewater could have met the national discharge standards of China. Besides, the mechanism of ammonia removal by ozone oxidation was proposed by detecting the products of the oxidation: ozone oxidation directly and ·OH oxidation; ammonia was mainly transformed into NO₃(-)-N, less into NO₂(-)-N, not into N₂.

  3. Ozone Depletion by Hydrofluorocarbons

    NASA Astrophysics Data System (ADS)

    Hurwitz, M.; Fleming, E. L.; Newman, P. A.; Li, F.; Mlawer, E. J.; Cady-Pereira, K. E.; Bailey, R.

    2015-12-01

    Hydrofluorocarbons (HFCs) are second-generation replacements for the chlorofluorocarbons (CFCs), halons and other substances that caused the 'ozone hole'. Atmospheric concentrations of HFCs are projected to increase dramatically in the coming decades. Coupled chemistry-climate simulations forced by these projections show that HFCs will impact the global atmosphere in 2050. As strong radiative forcers, HFCs modulate atmospheric temperature, thereby changing ozone-destroying catalytic cycles and enhancing the stratospheric circulation. These changes lead to a weak depletion of stratospheric ozone. Sensitivity simulations with the NASA Goddard Space Flight Center (GSFC) 2D model show that HFC-125 is the most important contributor to atmospheric change in 2050, as compared with HFC-23, HFC-32, HFC-134a and HFC-143a. Incorporating the interactions between chemistry, radiation and dynamics, for a likely 2050 climate, ozone depletion potentials (ODPs) for HFCs range from 4.3x10-4 to 3.5x10-2; previously HFCs were assumed to have negligible ODPs since these species lack chlorine or bromine atoms. The ozone impacts of HFCs are further investigated with the Goddard Earth Observing System Chemistry-Climate Model (GEOSCCM). The GEOSCCM is a three-dimensional, fully coupled ocean-atmosphere model with interactive stratospheric chemistry. Sensitivity simulations in which CO2, CFC-11 and HCFC-22 are enhanced individually are used as proxies for the atmospheric response to the HFC concentrations expected by the mid-21st century. Sensitivity simulations provide quantitative estimates of the impacts of these greenhouse gases on global total ozone, and can be used to assess their effects on the recovery of Antarctic ozone.

  4. Ozonation of Canadian Athabasca asphaltene

    NASA Astrophysics Data System (ADS)

    Cha, Zhixiong

    Application of ozonation in the petrochemical industry for heavy hydrocarbon upgrading has not been sufficiently explored. Among heavy hydrocarbons, asphaltenes are the heaviest and the most difficult fractions for analysis and treatment. Therefore, ozonation of asphaltenes presents an interesting application in the petrochemical industry. Commercial application of ozonation in the petrochemical industry has three obstacles: availability of an ozone-resistant and environmentally friendly solvent, the precipitation of ozonation intermediates during reaction, and recovery of the solvent and separation of the ozonation products. Preliminary ozonation of Athabasca oil sands asphaltene in nonparticipating solvents encountered serious precipitation of the ozonation intermediates. The precipitated intermediates could be polymeric ozonides and intermolecular ozonides or polymeric peroxides. Because the inhomogeneous reaction medium caused low ozone efficiency, various participating solvents such as methanol and acetic acid were added to form more soluble hydroperoxides. The mass balance results showed that on average, one asphaltene molecule reacted with 12 ozone molecules through the electrophilic reaction and the subsequent decomposition of ozonation intermediates generated acetone extractable products. GC/MS analysis of these compounds indicated that the free radical reactions could be important for generation of volatile products. The extensively ozonated asphaltene in the presence of participating solvents were refluxed with methanol to generate more volatile products. GC/MS analysis of the methanol-esterified ozonation products indicated that most volatile products were aliphatic carboxylic acid esters generated through cleavage of substituents. Reaction kinetics study showed that asphaltene ozonation was initially a diffusion rate-controlled reaction and later developed to a chemical reaction rate-controlled reaction after depletion of the reactive aromatic sites

  5. Coincident Observations of Surface Ozone and NMVOCs over Abu Dhabi

    NASA Astrophysics Data System (ADS)

    Abbasi, Naveed; Majeed, Tariq; Iqbal, Mazhar; Tarasick, David; Davies, Jonathan; Riemer, Daniel; Apel, Eric

    2016-07-01

    The vertical profiles of ozone are measured coincidently with non-methane volatile organic compounds (NMVOCs) at the meteorological site located at the Abu Dhabi international airport (latitude 24.45N; longitude 54.22E) during the years 2012 - 2014. Some of the profiles show elevated surface ozone >95 ppbv during the winter months (December, January and February). The ground-level NMVOCs obtained from the gas chromatography-flame ionization detection/mass spectrometry system also show elevated values of acetylene, ethane, propane, butane, pentane, benzene, and toluene. NMVOCs and ozone abundances in other seasons are much lower than the values in winter season. NMVOCs are emitted from an extensive number of sources in urban environments including fuel production, distribution, and consumption, and serve as precursor of ozone. Transport sources contribute a substantial portion of the NMVOC burden to the urban atmosphere in developed regions. Abu Dhabi is located at the edge of the Arabian Gulf and is highly affected by emissions from petrochemical industries in the neighboring Gulf region. The preliminary results indicate that wintertime enhancement in ozone is associated with large values of NMVOCs at Abu Dhabi. The domestic production of surface ozone is estimated from the combination of oxygen recombination and NMVOCs and compared with the data. It is estimated that about 40-50% of ozone in Abu Dhabi is transported from the neighbouring petrochemical industries. We will present ozone sounding and NMVOCs data and our model estimates of surface ozone, including a discussion on the high levels of the tropospheric ozone responsible for contaminating the air quality in the UAE. This work is supported by National Research Foundation, UAE.

  6. Recovery of the Ozone Layer: The Ozone Depleting Gas Index

    NASA Astrophysics Data System (ADS)

    Hofmann, David J.; Montzka, Stephen A.

    2009-01-01

    The stratospheric ozone layer, through absorption of solar ultraviolet radiation, protects all biological systems on Earth. In response to concerns over the depletion of the global ozone layer, the U.S. Clean Air Act as amended in 1990 mandates that NASA and NOAA monitor stratospheric ozone and ozone-depleting substances. This information is critical for assessing whether the Montreal Protocol on Substances That Deplete the Ozone Layer, an international treaty that entered into force in 1989 to protect the ozone layer, is having its intended effect of mitigating increases in harmful ultraviolet radiation. To provide the information necessary to satisfy this congressional mandate, both NASA and NOAA have instituted and maintained global monitoring programs to keep track of ozone-depleting gases as well as ozone itself. While data collected for the past 30 years have been used extensively in international assessments of ozone layer depletion science, the language of scientists often eludes the average citizen who has a considerable interest in the health of Earth's protective ultraviolet radiation shield. Are the ozone-destroying chemicals declining in the atmosphere? When will these chemicals decline to pre-ozone hole levels so that the Antarctic ozone hole might disappear? Will this timing be different in the stratosphere above midlatitudes?

  7. Children's Models of the Ozone Layer and Ozone Depletion.

    ERIC Educational Resources Information Center

    Christidou, Vasilia; Koulaidis, Vasilis

    1996-01-01

    The views of 40 primary students on ozone and its depletion were recorded through individual, semi-structured interviews. The data analysis resulted in the formation of a limited number of models concerning the distribution and role of ozone in the atmosphere, the depletion process, and the consequences of ozone depletion. Identifies five target…

  8. Ozone Contamination in Aircraft Cabins. Appendix A: Ozone toxicity

    NASA Technical Reports Server (NTRS)

    Melton, C. E.

    1979-01-01

    The recommendation that at various altitudes the amount of air with which ozone has mixed changes, thus changing the volume per volume relationship is discussed. The biological effects of ozone on human health and the amount of ozone necessary to produce symptoms were investigated.

  9. CONTRIBUTION TO INDOOR OZONE LEVELS OF AN OZONE GENERATOR

    EPA Science Inventory

    This report gives results of a study of a commonly used commercially available ozone generator, undertaken to determine its impact on indoor ozone levels. xperiment were conducted in a typical mechanically ventilated office and in a test house. he generated ozone and the in-room ...

  10. The Ozone Mapping and Profiler Suite: Extending the BUV Technique to Meet Future Ozone Measurement Requirements

    NASA Astrophysics Data System (ADS)

    Seftor, C. J.; Larsen, J. C.; Remund, Q.; Rodriguez, J. V.; Flynn, L. E.; Hilsenrath, E.

    2003-12-01

    Measurements from the original TOMS and SBUV instruments onboard the Nimbus-7 spacecraft form one of the cornerstones of satellite-based studies of long-term ozone trends. These sensors established the use of the backscattered ultraviolet (BUV) technique, along with calibration techniques based on the measurement of solar flux, to determine and monitor total column and profile ozone amounts on a global, daily basis. They also provided the foundation for the design and development of the Meteor-3, ADEOS, and Earth Probe TOMS sensors and NOAA's successful SBUV/2 series of ozone sensors, whose total column and profile ozone measurements continue through today to extend the set of ozone measurements begun by Nimbus-7. The Ozone Mapping and Profiler Suite (OMPS) is a new generation of hyperspectral BUV sensors that are currently in development for the National Polar-orbiting Operational Environmental Satellite System (NPOESS). These sensors, whose first launch will be onboard the NPOESS Preparatory Project (NPP) satellite in 2006, are designed to continue this long-term data set with better accuracy, precision, and other requirements than any of the total column and profile ozone retrieval systems currently in orbit. In developing the OMPS suite to meet the NPOESS requirements, we systematically analyzed the performance of current BUV systems. We determined that the TOMS sensor and algorithm provided a strong starting point for the development of the OMPS total column ozone retrieval system and we identified areas where design improvements in both would lead to the performance necessary to meet the NPOESS requirements. Since we also determined that an SBUV-type nadir-looking sensor would not meet the NPOESS profile ozone requirements, the OMPS system includes both a nadir profiling sensor to provide measurements that directly link to the SBUV and SBUV/2 heritage dataset and a sensor-algorithm system that uses the limb-scattered BUV/Visible technique pioneered by SOLSE

  11. "OZONE SOURCE APPORTIONMENT IN CMAQ'

    EPA Science Inventory

    Ozone source attribution has been used to support various policy purposes including interstate transport (Cross State Air Pollution Rule) by U.S. EPA and ozone nonattainment area designations by State agencies. Common scientific applications include tracking intercontinental tran...

  12. Ozone Minimums, 1979 to 2013

    NASA Video Gallery

    Minimum concentration of ozone in the southern hemisphere for each year from 1979-2013 (there is no data from 1995). Each image is the day of the year with the lowest concentration of ozone. A grap...

  13. Ozone studies in the Paso del Norte region

    NASA Astrophysics Data System (ADS)

    Becerra-Davila, Fernando

    The Paso del Norte region forms the largest contiguous bi-national conglomerate on the US-Mexico border. With a combined population of around 2 million inhabitants, the Paso del Norte region is isolated, more than 500 km away from the nearest urban area of comparable size, thus making it an ideal location for air quality studies of an isolated urban environment. The meteorological conditions leading to a high ozone episode in this region, such as the historical ozone episode of June 2006, are analyzed. It is well known that stagnation and minimal winds, high temperatures, and pressure ridges over the region are conducive to high ozone episodes. In addition, the planetary boundary height is studied to understand its impact on high ozone episodes. Several studies report that ground level ozone non-attainment regulations could be caused not only by local emissions, but also by atmospheric transport. In this work the atmospheric advection of pollutants into the region is analyzed using HYSPLIT backward trajectories. Furthermore, a novel backward trajectory clustering technique is implemented for the summer of 2006. The "ozone weekend effect" (OWE) is a phenomenon by which in some geographical regions ambient ozone concentrations tend to be higher on weekends than on weekdays, despite the lower emissions of ozone precursors during those days. The observed local OWE has never previously been studied in terms of the photolysis rates of four of the main ozone precursors. In this research a novel method that allows the calculation of actinic fluxes, photolysis frequencies and photolysis rates with a high degree of accuracy and reliability has been developed. This method utilizes a combination of the experimental data available for this region in conjunction with a radiative transfer model (TUV model). Three weekend-weekday cases during summers 2006, 2009 and 2010 are studied in this work. In this research, the photolysis impact on the local OWE is studied. The results

  14. Analysis of 2010-2014 Ground-Level Ozone at Trinidad Head, CA

    NASA Astrophysics Data System (ADS)

    Lennartson, E.; McClure-Begley, A.; Petropavlovskikh, I. V.; Leonard, M.

    2015-12-01

    High concentrations of ground-level ozone in the troposphere have negative impacts on human health and other biological organisms. As the US Environmental Protection Agency (EPA) is proposing to lower the National Ambient Air Quality Standard (NAAQS) for ozone from 75 to 65-70 parts per billion (ppb), it is important to further study the relationship between both anthropogenic and natural pollutants that lead to production and accumulation of surface ozone. Ground-level ozone data from Trinidad Head, California (THD) was analyzed from 2010-2014 to investigate the factors contributing to high ground-level ozone events. For this research project, a high ozone event was defined as ground-level ozone readings greater than the 90th percentile of the seasonal ozone variability observed during the 2003-2014 period. The ozone exceedances were also required to last for three continuous hours or more. Meteorological parameters, such as wind speed and synoptic patterns, were taken into account. In addition, impacts related to stratospheric intrusions, Asian pollution transport, and the influence of local forest fires were considered. We show that high ground-level ozone events at THD occur during a dominant wind direction and are highly dependent on the origin of the air mass. This understanding of enhanced ground-level ozone drivers will provide a foundational knowledge of climate adaptation and mitigation with improved scientific understanding of the changing climate and its impacts.

  15. What would have happened to the ozone layer if chlorofluorocarbons (CFCs) had not been regulated?

    NASA Astrophysics Data System (ADS)

    Newman, P. A.; Oman, L. D.; Douglass, A. R.; Fleming, E. L.; Frith, S. M.; Hurwitz, M. M.; Kawa, S. R.; Jackman, C. H.; Krotkov, N. A.; Nash, E. R.; Nielsen, J. E.; Pawson, S.; Stolarski, R. S.; Velders, G. J.

    2008-12-01

    Ozone depletion by chlorofluorocarbons (CFCs) was first proposed by Molina and Rowland in their 1974 Nature paper. Since that time, the scientific connection between ozone losses and CFCs and other ozone depleting substances (ODSs) has been firmly established with laboratory measurements, atmospheric observations, and modeling research. The nations of the world implemented the Montreal Protocol (and amendments) which stopped ODS production in 1992. In this presentation we use a fully coupled radiation- chemical-dynamical model to simulate a future world where ODSs were never regulated and ODS production grew at an annual rate of 3%. In this "world avoided" simulation, 17% of the globally average column ozone is destroyed by 2020, and 67% is destroyed by 2065 in comparison to 1980. Large ozone depletions in the polar region become year-round rather than just seasonal as is currently observed in the Antarctic ozone hole. Very large temperature decreases are observed in response to circulation changes and decreased shortwave radiation absorption by ozone. Ozone levels in the tropical lower stratosphere remain constant until about 2053 and then collapse to near zero by 2058 as a result of heterogeneous chemical processes (as currently observed in the Antarctic ozone hole). The tropical cooling that triggers the ozone collapse is caused by an increase of the tropical upwelling. In response to ozone changes, ultraviolet (UV) radiation increases, tripling the erythemal (sunburn) radiation in the northern summer mid-latitudes by 2065.

  16. Ozone depletion by hydrofluorocarbons

    NASA Astrophysics Data System (ADS)

    Hurwitz, Margaret M.; Fleming, Eric L.; Newman, Paul A.; Li, Feng; Mlawer, Eli; Cady-Pereira, Karen; Bailey, Roshelle

    2015-10-01

    Atmospheric concentrations of hydrofluorocarbons (HFCs) are projected to increase considerably in the coming decades. Chemistry climate model simulations forced by current projections show that HFCs will impact the global atmosphere increasingly through 2050. As strong radiative forcers, HFCs increase tropospheric and stratospheric temperatures, thereby enhancing ozone-destroying catalytic cycles and modifying the atmospheric circulation. These changes lead to a weak depletion of stratospheric ozone. Simulations with the NASA Goddard Space Flight Center 2-D model show that HFC-125 is the most important contributor to HFC-related atmospheric change in 2050; its effects are comparable to the combined impacts of HFC-23, HFC-32, HFC-134a, and HFC-143a. Incorporating the interactions between chemistry, radiation, and dynamics, ozone depletion potentials (ODPs) for HFCs range from 0.39 × 10-3 to 30.0 × 10-3, approximately 100 times larger than previous ODP estimates which were based solely on chemical effects.

  17. Application of ozone for reduction of mycological infection in wheat grain.

    PubMed

    Raila, Algirdas; Lugauskas, Albinas; Steponavicius, Dainius; Railiene, Marija; Steponaviciene, Ausra; Zvicevicius, Egidijus

    2006-01-01

    In 2004-2005 means were sought to clean grain from microbiological contamination during transportation and storage. For this purpose, grains with a moisture content of 23.2 % of the "Tauras" variety were selected and ventilated daily for 8 hours until grain wetness was reduced to 14.0 %. The effect of ventilation duration and ozone impact was evaluated according to the changes in grain contamination with micromycetes propagules (cfu x g (-1)), and alternation of micromycetes species on the grain surface. At drying grains by active ventilation with an ozone--air mixture, at O (3) concentration of 700 ppb, the drying period was reduced by about 20 %, and mycological contamination depends on initial grain moisture content (w): when w=15.2 %, contamination was reduced by up to 2.2 times, and when w=22.0 %--up to 3 times. At the same time, the composition of micromycetes species on the grain surface changed significantly: in non-ventilated grain there were detected micromycetes of 26 species, and in ventilated grain--of 11 species. Efficient ozone impact was established only when the mound of wet (w>18.0 %) grains was exposed to ozone.

  18. Projected changes in high ozone pollution events over the Eastern United States over the 21st century

    NASA Astrophysics Data System (ADS)

    Fiore, A. M.; Rieder, H.; Horowitz, L. W.; Naik, V.

    2013-12-01

    Over the past few decades, thresholds for the United States (US) National Ambient Air Quality Standard (NAAQS) for ozone (O3), established to protect public health and welfare, have been lowered repeatedly. We recently applied methods from extreme value theory (EVT) to maximum daily 8-hour average ozone (MDA8 O3) observed by the Clean Air Status and Trends Network (CASTNet) to quantify the significant decline in both frequency and magnitude of high O3 pollution events over the Eastern US from 1988 to 2009. These improvements to Eastern US air quality have been reported in prior studies and result from changes in air quality regulations and subsequent control measures (e.g., the 'NOx SIP Call') as demonstrated by our analysis of 1-year and 5-year return levels. Here we extend this analysis to future projections of high O3 pollution events spanning the course of the 21st century. To this aim, we analyze simulations from the GFDL CM3 chemistry-climate model under selected Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5 (representing a moderate and strong climate warming with a global mean temperature change by 2100 compared to present day of +2.3K and +4.5K, respectively). Under both scenarios, NOx emissions decrease by ~80% over North America by 2100 under the assumption of aggressive ozone pollution controls. A third scenario, termed RCP4.5_WMGG, in which well-mixed greenhouse gases follow the RCP4.5 scenario but O3 and aerosol precursor emissions are held at 2005 levels, enables us to isolate the role of climate change from that of emission reductions. As we find a positive bias in GFDL CM3 MDA8 O3 compared to the Eastern US CASTNet O3 measurements during summer (a common feature in the current generation of models), we develop a correction method based on quantile-mapping. This bias correction effectively removes the model bias while preserving the temporal changes in MDA8 O3 as simulated under different RCPs over the course of the 21st

  19. Projected changes in high ozone pollution events over the Eastern United States over the 21st century

    NASA Astrophysics Data System (ADS)

    Rieder, Harald E.; Fiore, Arlene M.; Horrowitz, Larry W.; Naik, Vaishali

    2014-05-01

    Over the past few decades, thresholds for the United States (US) National Ambient Air Quality Standard (NAAQS) for ozone (O3), established to protect public health and welfare, have been lowered repeatedly. We recently applied methods from extreme value theory (EVT) to maximum daily 8-hour average ozone (MDA8 O3) observed by the Clean Air Status and Trends Network (CASTNet) to quantify the significant decline in both frequency and magnitude of high O3 pollution events over the Eastern US from 1988 to 2009. These improvements to Eastern US air quality have been reported in prior studies and result from changes in air quality regulations and subsequent control measures (e.g., the "NOx SIP Call") as demonstrated by our analysis of 1-year and 5-year return levels. Here we extend this analysis to future projections of high O3 pollution events spanning the course of the 21st century. To this aim, we analyze simulations from the GFDL CM3 chemistry-climate model under selected Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5 (representing a moderate and strong climate warming with a global mean temperature change by 2100 compared to present day of +2.3K and +4.5K, respectively). Under both scenarios, NOx emissions decrease by ~80% over North America by 2100 under the assumption of aggressive ozone pollution controls. A third scenario, termed RCP4.5_WMGG, in which well-mixed greenhouse gases follow the RCP4.5 scenario but O3 and aerosol precursor emissions are held at 2005 levels, enables us to isolate the role of climate change from that of emission reductions. As we find a positive bias in GFDL CM3 MDA8 O3 compared to the Eastern US CASTNet O3 measurements during summer (a common feature in the current generation of models), we develop a correction method based on quantile-mapping. This bias correction effectively removes the model bias while preserving the temporal changes in MDA8 O3 as simulated under different RCPs over the course of the 21st

  20. Climate Effects on Ozone Concentrations in California

    NASA Astrophysics Data System (ADS)

    Mahmud, A.; Kleeman, M.

    2007-12-01

    The statistical relationship between the daily 1-hr maximum ozone concentrations and the daily maximum upper air temperature was explored for California's two most heavily polluted air basins: the South Coast Air Basin (SoCAB) and the San Joaquin Valley (SJV). The temperature at an elevation of 850-milibar pressure (T850) for the period 1980 - 2004 was obtained from the National Center for Environmental Prediction (NCEP) / National Center for Atmospheric Research (NCAR) Reanalysis1 dataset for Riverside (SoCAB) and Fresno (SJV). Daily 1- hr maximum ozone concentrations were provided by the California Air Resources Board (CARB) for Upland (SoCAB) and Parlier (SJV) for the same time period. The ozone concentrations at any given value of T850 were approximately normally distributed. The 25%, 50%, and 75% quartile ozone concentrations increased linearly with T850, reflecting the effect of temperature on emissions and chemical reaction rates. A 2-D Lagrangian (trajectory) form of the UCD/CIT photochemical air quality model was used to explain the standard deviation of the ozone concentrations at each value of T850. Three-day back trajectories were calculated for a typical air quality episode. The base case trajectory routes were then perturbed by adding stochastic bias to the wind-field. Temperature, relative humidity, mixing height, initial concentrations for VOC concentrations, background ozone concentrations, time of year and overall emissions were also perturbed in a realistic fashion during this study. A total of 62 model simulations were performed and the results were analyzed to show that long term changes to emissions inventories were the largest sources of ozone variability at a fixed value of T850. Projections of future T850 values in California were obtained from the Geophysical Fluid Dynamics Laboratory (GFDL) model under the Intergovernmental Panel on Climate Change (IPCC) A2 and B1 emissions scenarios for the years from 2001 to 2100. The future temperature

  1. Ozone and cardiovascular injury.

    PubMed

    Srebot, Vera; Gianicolo, Emilio A L; Rainaldi, Giuseppe; Trivella, Maria Giovanna; Sicari, Rosa

    2009-06-24

    Air pollution is increasingly recognized as an important and modifiable determinant of cardiovascular diseases in urban communities. The potential detrimental effects are both acute and chronic having a strong impact on morbidity and mortality. The acute exposure to pollutants has been linked to adverse cardiovascular events such as myocardial infarction, heart failure and life-threatening arrhythmias. The long-terms effects are related to the lifetime risk of death from cardiac causes. The WHO estimates that air pollution is responsible for 3 million premature deaths each year. The evidence supporting these data is very strong nonetheless, epidemiologic and observational data have the main limitation of imprecise measurements. Moreover, the lack of clinical experimental models makes it difficult to demonstrate the individual risk. The other limitation is related to the lack of a clear mechanism explaining the effects of pollution on cardiovascular mortality. In the present review we will explore the epidemiological, clinical and experimental evidence of the effects of ozone on cardiovascular diseases. The pathophysiologic consequences of air pollutant exposures have been extensively investigated in pulmonary systems, and it is clear that some of the major components of air pollution (e.g. ozone and particulate matter) can initiate and exacerbate lung disease in humans 1. It is possible that pulmonary oxidant stress mediated by particulate matter and/or ozone (O3) exposure can result in downstream perturbations in the cardiovasculature, as the pulmonary and cardiovascular systems are intricately associated, and it is well documented that specific environmental toxins (such as tobacco smoke 2) introduced through the lungs can initiate and/or accelerate cardiovascular disease development. Indeed, several epidemiologic studies have proved that there is an association between PM and O3 and the increased incidence of cardiovascular morbidity and mortality 3. Most of the

  2. SAGE II Ozone Analysis

    NASA Technical Reports Server (NTRS)

    Cunnold, Derek; Wang, Ray

    2002-01-01

    Publications from 1999-2002 describing research funded by the SAGE II contract to Dr. Cunnold and Dr. Wang are listed below. Our most recent accomplishments include a detailed analysis of the quality of SAGE II, v6.1, ozone measurements below 20 km altitude (Wang et al., 2002 and Kar et al., 2002) and an analysis of the consistency between SAGE upper stratospheric ozone trends and model predictions with emphasis on hemispheric asymmetry (Li et al., 2001). Abstracts of the 11 papers are attached.

  3. Tropospheric ozone in the vicinity of the ozone hole - 1987 Airborne Antarctic Ozone Experiment

    NASA Technical Reports Server (NTRS)

    Gregory, Gerald L.; Warren, Linda S.; Hypes, Warren D.; Tuck, Adrian F.; Kelly, Kenneth K.; Krueger, Arlin J.

    1989-01-01

    Results are presented on ozone measurements in the upper troposphere/lower stratosphere over Antarctica, obtained by NASA DC-8 aircraft during the August/September 1987 Airborne Antarctic Ozone Experiment. The ozone mixing ratios as high as several hundred ppbv were measured, but in all cases these ratios were observed in pockets of upper atmospheric air, both in the vicinity of and away from the location of the ozone hole. The background ozone values in the surrounding troposphere were typically in the range of 20-50 ppbv. Correlation of tropospheric ozone observations with the boundaries of the ozone hole differed in the course of the experiment. During the August 28 - September 2 flights, encounters with ozone-rich air were limited, and the background tropospheric ozone appeared to decrease beneath the hole. For the later flights, and as the ozone hole deepened, the ozone-rich air was frequently observed in the vicinity of the hole, and the average ozone values at the flight altitude were frequently higher than the background values.

  4. Antarctic total ozone in 1958

    SciTech Connect

    Newman, P.A. )

    1994-04-22

    The Antarctic ozone hole results from catalytic destruction of ozone by chlorine radicals. The hole develops in August, reaches its full depth in early October, and is gone by early December of each year. Extremely low total ozone measurements were made at the Antarctic Dumont d'Urville station in 1958. These measurements were derived from spectrographic plates of the blue sky, the moon, and two stars. These Dumont plate data are inconsistent with 1958 Dobson spectrophotometer ozone measurements, inconsistent with present-day Antarctic observations, and inconsistent with meteorological and theoretical information. There is no credible evidence for an ozone hole in 1958.

  5. Karlson ozone sterilizer. Final report

    SciTech Connect

    Karlson, E.

    1984-05-07

    The authors have a functional sterilization system employing ozone as a sterilization agent. This final report covers the work that led to the first medical sterilizer using ozone as the sterilizing agent. The specifications and the final design were set by hospital operating room personnel and public safety standards. Work on kill tests using bacteria, viruses and fungi determined the necessary time and concentration of ozone necessary for sterilization. These data were used in the Karlson Ozone Sterilizer to determine the length of the steps of the operating cycle and the concentration of ozone to be used. 27 references.

  6. Precision ozone vapor pressure measurements

    NASA Technical Reports Server (NTRS)

    Hanson, D.; Mauersberger, K.

    1985-01-01

    The vapor pressure above liquid ozone has been measured with a high accuracy over a temperature range of 85 to 95 K. At the boiling point of liquid argon (87.3 K) an ozone vapor pressure of 0.0403 Torr was obtained with an accuracy of + or - 0.7 percent. A least square fit of the data provided the Clausius-Clapeyron equation for liquid ozone; a latent heat of 82.7 cal/g was calculated. High-precision vapor pressure data are expected to aid research in atmospheric ozone measurements and in many laboratory ozone studies such as measurements of cross sections and reaction rates.

  7. Normally Expected Aberrations in the 8-hour Dynamic EKG

    NASA Technical Reports Server (NTRS)

    Fleck, R. L.; Arnoldi, L. B.; Townsend, J. C.; Tonesk, X.

    1970-01-01

    The establishment of norms for interpreting long term dynamic electrocardiograms is attempted by correlating a completely disease symptom and cardiac risk factor free sample with a non-pure sample in the direction of normality on various variables. Out of a population of 362 subjects exposed to dynamic electrocardiogram testing, a discrimination between normals and abnormals in terms of traditional risk factors was observed. The two groups differed significantly on the following variables: cholesterol, smoking, systolic blood pressure, white blood count, fasting blood sugar, uric acid, resting EKG, year of birth, and coronary insufficiency.

  8. Use of AIRS, OMI, MLS, and TES Data in Assessing Forest Ecosystem Exposure to Ozone

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph P.

    2007-01-01

    Ground-level ozone at high levels poses health threats to exposed flora and fauna, including negative impacts to human health. While concern is common regarding depletion of ozone in the stratosphere, portions of the urban and rural United States periodically have high ambient levels of tropospheric ozone on the ground. Ozone pollution can cause a variety of impacts to susceptible vegetation (e.g., Ponderosa and Jeffrey pine species in the southwestern United States), such as stunted growth, alteration of growth form, needle or leaf chlorosis, and impaired ability to withstand drought-induced water stress. In addition, Southern Californian forests with high ozone exposures have been recently subject to multiyear droughts that have led to extensive forest overstory mortality from insect outbreaks and increased incidence of wildfires. Residual forests in these impacted areas may be more vulnerable to high ozone exposures and to other forest threats than ever before. NASA sensors collect a wealth of atmospheric data that have been used recently for mapping and monitoring regional tropospheric ozone levels. AIRS (Atmospheric Infrared Sounder), OMI (Ozone Monitoring Instrument), MLS (Microwave Limb Sounder), and TES (Tropospheric Emission Spectrometer) data could be used to assess forest ecosystem exposure to ozone. Such NASA data hold promise for providing better or at least complementary synoptic information on ground-level ozone levels that Federal agency partners can use to assess forest health trends and to mitigate the threats as needed in compliance with Federal laws and mandates. NASA data products on ozone concentrations may be able to aid applications of DSTs (decision support tools) adopted by the USDA FS (U.S. Department of Agriculture Forest Service) and by the NPS (National Park Service), such as the Ozone Calculator, in which ground ozone estimates are employed to assess ozone impacts to forested vegetation.

  9. Quasi-biennial modulation of the Antarctic ozone depletion

    NASA Technical Reports Server (NTRS)

    Lait, Leslie R.; Schoeberl, Mark R.; Newman, Paul A.

    1989-01-01

    The quasi-biennial oscillation (QBO) in total ozone and temperature has been extracted from 9 years of Total Ozone Mapping Spectrometer (TOMS) observations and National Meteorological Center (NMC) analyses. Years in which QBO-related variations in the total ozone and temperature are positive are found to correspond to years with smaller September Antarctic total ozone hole decline rates and vice versa. The QBO appears to be responsible for September decline rate deviations up to 0.4 Dobson units (DU) per day. Also, the QBO at mid-latitudes appears to be better correlated with the 30-mbar tropical QBO winds than with those at 50 mbar. Possible mechanisms that would explain these phenomena are discussed.

  10. The Ozone Show.

    ERIC Educational Resources Information Center

    Mathieu, Aaron

    2000-01-01

    Uses a talk show activity for a final assessment tool for students to debate about the ozone hole. Students are assessed on five areas: (1) cooperative learning; (2) the written component; (3) content; (4) self-evaluation; and (5) peer evaluation. (SAH)

  11. Ozone and Cavitation Combination

    NASA Astrophysics Data System (ADS)

    Carreon, Ernestina; Traversoni, Leonardo

    2009-09-01

    From laboratory measurements it is well known that the addition of ozone and cavitation enhances the properties of both, understanding for that the ones related to disinfection and carbon removal from waste water. This paper shows modeling of such phenomena that gives some light to the understanding of it and also provides the opportunity to improve the effectiveness of the current procedures.

  12. Dobson ozone spectrophotometer modification.

    NASA Technical Reports Server (NTRS)

    Komhyr, W. D.; Grass, R. D.

    1972-01-01

    Description of a modified version of the Dobson ozone spectrophotometer in which several outdated electronic design features have been replaced by circuitry embodying more modern design concepts. The resulting improvement in performance characteristics has been obtained without changing the principle of operation of the original instrument.

  13. Ozone decomposing filter

    DOEpatents

    Simandl, Ronald F.; Brown, John D.; Whinnery, Jr., LeRoy L.

    1999-01-01

    In an improved ozone decomposing air filter carbon fibers are held together with a carbonized binder in a perforated structure. The structure is made by combining rayon fibers with gelatin, forming the mixture in a mold, freeze-drying, and vacuum baking.

  14. Ozone, CFCs and aerosols.

    PubMed

    1989-07-01

    Chlorofluorocarbons (CFCs) are, from the chemist's point of view, unique compounds with very valuable properties. They are inert, cheap and stable. But they also have devastating effects on the environment, destroying the ozone layer and adding to global warming or the greenhouse effect.

  15. Ozone decomposing filter

    SciTech Connect

    Simandl, R.F.; Brown, J.D.; Whinnery, L.L. Jr.

    1999-11-02

    In an improved ozone decomposing air filter carbon fibers are held together with a carbonized binder in a perforated structure. The structure is made by combining rayon fibers with gelatin, forming the mixture in a mold, freeze-drying, and vacuum baking.

  16. The 1981-1982 NCLAN (National Crop Loss Assessment Network) program at LLNL: The effects of ozone and sulfur dioxide, singly and in combination, on field-grown tomato

    SciTech Connect

    Surano, K.A.; Mutters, R.G.; Temple, P.J.; Bingham, G.E.; Kercher, J.R.; Shinn, J.H.

    1987-07-01

    The combined effects of ozone (O/sub 3/) and sulfur dioxide (SO/sub 2/) exposures on tomato (Lycopersicon esculentum Mill.) crop yields were measured during the 1981 and 1982 growing seasons. The effort, part of the National Crop Loss Assessment Network (NCLAN), had the objective of determining the yield dose response of tomato grown under commercial conditions. Dose response was determined using step-wise multiple regression techniques and was expressed as reduction in marketable yield as a function of increased pollutant levels. The crops were harvested during mid-September 1981 and during mid-October 1982. No O/sub 3/- or So/sub 2/-induced visible injury symptons (lesions, chlorosis, or becrosis) were apparent on foliage or fruits. Total marketable fruit fresh weight was used as the dependent variable in the regression analysis because it most closely represented the economic value of the crop. Comparison of chambered- and companion-plot data showed that the chambers themselves caused significant effects on the crop. Yields were reduced 12% in 1981 and 24% in 1982 due to the chambers. There was also more unripened fruit within the chambers because of chamber-induced uneven distribution of an aerially-applied ripening agent. Dose-response results were independent of the chamber effects. Based on companion-plot data, the yield of the crop in the research area was 65/plus minus/2 Mg ha/sup /minus/1/ in both years. The research-area yields correlated well with those from the adjacent commercial plantation. With respect to tomato production in the San Joaquin Valley, we recommend that an air quality management strategy be adopted to contain ambient O/sub 3/ concentrations at or below present levels. Containment at present levels would avoid O/sub 3/-induced tomato yield reductions greater than 7%, even during atypical years such as 1982. 26 refs., 17 figs., 9 tabs.

  17. Field Testing of New Interference-Free Ambient Ozone Monitors

    NASA Astrophysics Data System (ADS)

    Ollison, W. M.; Capel, J.; Crow, W.; Johnson, T.; Spicer, C. W.

    2013-05-01

    Multibillion-dollar strategies control ambient air ozone (O3) levels in the U.S. so it is essential that the O3 measurements made for developing state implementation plans, assessing population risks, and determining compliance with regulations be accurate. The predominant U.S. regulatory method employed to monitor ambient O3 is ultraviolet (254 nm) photometry and many previous studies have demonstrated positive interferences associated with this technology. We evaluate two new humidity-controlled commercial instruments - a 2B Technology Model 211 ultraviolet O3 photometer that replaces its conventional MnO2 scrubber with gas-phase NO titration and a Teledyne-API Model 265E NO-O3 chemiluminescence monitor - both designed to minimize the aromatic organic, mercury, and water vapor interferences common to O3 photometers. New units were paired with conventional photometers sampling indoor, outdoor, and in-vehicle environments where populations spend most of their time. Overall, during the fixed-site monitor comparisons in Houston, TX, the three instruments were highly correlated (r2 ≥ 0.99) with regression slopes of 1.00 ± 0.01, and O3 averaged over the study period agreed within 1 ppb; however, U.S. O3 standard compliance depends on fourth highest annual daily maximum 8-hour O3 values, so urban monitors must measure accurately during typically hot, humid, and stagnant O3-conducive day conditions. Conventional photometers reported the highest values for the four highest 8-hour daily maxima during our three month late summer test period, with 8-hour average differences between the new and conventional monitors ranging up to 4 ppb. In paired 10-minute average sampling with a Model 211 in Durham, NC, conventional photometers generally exhibited modest positive interference bias (under 5 ppb) in 176 sampled residences, shops, malls, restaurants, offices, parks, roadways, and vehicles; however, in six percent of our samples indoor differences exceeded 10 ppb and in two

  18. 75 FR 45075 - Federal Implementation Plans To Reduce Interstate Transport of Fine Particulate Matter and Ozone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ... Interstate Transport of Fine Particulate Matter and Ozone AGENCY: Environmental Protection Agency (EPA... Matter and Ozone'' (Transport Rule) which is published elsewhere in today's issue of the Federal Register... 2006 fine particulate matter (PM 2.5 ) national ambient air quality standards (NAAQS) and the...

  19. 500 Nations: The History of the Americas.

    ERIC Educational Resources Information Center

    Huntinghorse, D. Marisa

    1995-01-01

    Describes an 8-hour television documentary, "500 Nations," that uses 3-dimensional computer images to recreate the appearance of Indian villages before the arrival of Europeans. Documentary makers sought out considerable Indian input and hope to increase the general public's awareness and understanding of American Indian history in North America.…

  20. Tropospheric ozone in the vicinity of the ozone hole: 1987 Airborne Antarctic Ozone Experiment

    SciTech Connect

    Gregory, G.L.; Warren, L.S. ); Hypes, W.D. ); Tuck, A.F.; Kelly, K.K. ); Krueger, A.J. )

    1989-11-30

    Tropospheric ozone measurements over Antarctica aboard the NASA DC-8 aircraft are summarized. As part of the August/September 1987 Airborne Antarctic Ozone Experiment, the aircraft flew 13 missions covering a latitude of 53{degree}-90{degree}S, at altitudes to 13 km. Ozone mixing ratios as high as several hundred parts per billion by volume (ppbv) were measured, but in all cases these ratios were observed in pockets or patches of upper atmospheric air. These pockets were observed both in the vicinity of and away from the location of the ozone hole. At times, and as a result of these pockets, the ozone levels at the flight altitude of the aircraft, as averaged beneath the boundaries of the stratospheric ozone hole, were 2-3 times higher than background tropospheric values. The data suggest that the ozone-rich air seldom penetrated below about 9-km altitude. Background ozone values in the surrounding troposphere were typically in the range of 20-50 ppbv. Correlation of tropospheric ozone observations with the boundaries of the ozone hole differed during the experiment. During the early flights (August 28 through September 2), encounters with ozone-rich air were limited and background tropospheric ozone (at the flight altitude) appeared to decrease beneath the hole. For many of the later flights, and as the hole deepened, the reverse was noted, in that ozone-rich air was frequently observed in the vicinity of the hole and, as noted earlier, average ozone at the flight altitude was frequently higher than background values.

  1. Projecting Policy-Relevant Metrics to Characterize Changing Ozone Extremes over the US: Variations by Region, Season and Scenario

    NASA Astrophysics Data System (ADS)

    Rieder, H. E.; Fiore, A. M.; Correa, G. J. P.; Clifton, O.; Horowitz, L. W.; Naik, V.

    2014-12-01

    Nitrogen oxide (NOx) emission controls have led to improved air quality (particularly in the Eastern US) over the past two decades, but concerns have been raised that climate warming may offset some of these gains in the coming decades. Here we address these concerns by analyzing the effect of projected future changes of emissions and climate, in isolation and combination, on US surface ozone (O3) during the 21st century in an ensemble of simulations (3 members per scenario) performed with the GFDL chemistry-climate model CM3. We analyze two Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5. Under both scenarios, NOx emissions decrease by ~80% over North America by 2100. In additional 3-member ensemble simulations, termed RCP4.5_WMGG and RCP8.5_WMGG, well-mixed greenhouse gases follow the respective RCP but O3 and aerosol precursor emissions are held at 2005 levels. These simulations enable us to isolate the role of well-mixed greenhouse gas induced climate change from that of emission reductions. Another set of simulations, following RCP8.5 but with methane (CH4) held fixed at 2005 levels, termed RCP8.5_2005CH4, allows us to quantify the background influence of CH4 on O3. For each season, we examine changes in the surface O3 distribution over the US during the 21st century, calculating policy relevant statistics: days above the current national ambient air quality standard (NAAQS) of 75 ppb and other proposed future levels, as well as the probabilistic 1-year return levels for maximum daily 8-hour average ozone (MDA8 O3), within each model grid cell. Specifically, we analyze: (i) regional and seasonal changes in the frequency and return level of high O3 pollution events during the 21st century, as well as (ii) differences among the RCPs by the middle and end of the 21st century. We find that the response of surface O3 to changes in emissions and climate varies strongly, seasonally and spatially, with certain regions more prone to a 'climate

  2. Projecting policy-relevant metrics to characterize changing ozone extremes over the US: Variations by region, season and scenario

    NASA Astrophysics Data System (ADS)

    Rieder, Harald E.; Fiore, Arlene M.; Correa, Gus; Clifton, Olivia; Horrowitz, Larry W.; Naik, Vaishali

    2015-04-01

    Nitrogen oxide (NOx) emission controls have led to improved air quality (particularly in the Eastern US) over the past two decades, but concerns have been raised that climate warming may offset some of these gains in the coming decades. Here we address these concerns by analyzing the effect of projected future changes of emissions and climate, in isolation and combination, on US surface ozone (O3) during the 21st century in an ensemble of simulations (3 members per scenario) performed with the GFDL chemistry-climate model CM3. We analyze two Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5. Under both scenarios, NOx emissions decrease by ~80% over North America by 2100. In additional 3-member ensemble simulations, termed RCP4.5_WMGG and RCP8.5_WMGG, well-mixed greenhouse gases follow the respective RCP but O3 and aerosol precursor emissions are held at 2005 levels. These simulations enable us to isolate the role of well-mixed greenhouse gas induced climate change from that of emission reductions. Another set of simulations, following RCP8.5 but with methane (CH4) held fixed at 2005 levels, termed RCP8.5_2005CH4, allows us to quantify the background influence of CH4 on O3. For each season, we examine changes in the surface O3 distribution over the US during the 21st century, calculating policy relevant statistics: days above the current national ambient air quality standard (NAAQS) of 75 ppb and other proposed future levels, as well as the probabilistic 1-year return levels for maximum daily 8-hour average ozone (MDA8 O3), within each model grid cell. Specifically, we analyze: (i) regional and seasonal changes in the frequency and return level of high O3 pollution events during the 21st century, as well as (ii) differences among the RCPs by the middle and end of the 21st century. We find that the response of surface O3 to changes in emissions and climate varies strongly, seasonally and spatially, with certain regions more prone to a 'climate

  3. 16 CFR 260.11 - Ozone-safe and ozone-friendly claims.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... friendly to, the ozone layer or the atmosphere. Example 1: A product is labeled “ozone-friendly.” The claim... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Ozone-safe and ozone-friendly claims. 260.11... THE USE OF ENVIRONMENTAL MARKETING CLAIMS § 260.11 Ozone-safe and ozone-friendly claims. It...

  4. 16 CFR 260.11 - Ozone-safe and ozone-friendly claims.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... friendly to, the ozone layer or the atmosphere. Example 1: A product is labeled “ozone-friendly.” The claim... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Ozone-safe and ozone-friendly claims. 260.11... THE USE OF ENVIRONMENTAL MARKETING CLAIMS § 260.11 Ozone-safe and ozone-friendly claims. It...

  5. Ozone variability over Antarctic continent

    NASA Astrophysics Data System (ADS)

    Concepcion Parrondo, Mā; Yela, Margarita; Gil, Manuel; Ochoa, Hector

    2010-05-01

    Ozonesoundings data from Antarctic Belgrano Station (78°S, 34°W) carried out since 1999 are used to analyze the inter-annual variability of ozone in the troposphere and lower stratosphere. Tropospheric ozone has been calculated integrating the ozone content from the ground up to the ozone tropopause for each ozonesounding using Betan et al. [1996], definition. The annual cycle of the tropospheric ozone values shows an increase from summer to winter months. In August, tropospheric ozone almost doubles the values in February. Dynamical and chemical factors responsible of this behaviour are presented. Ozone loss rate during September in the lower stratosphere for the eleven year record is presented. The highest inter-annual ozone variability in observed during November and December in the lower stratosphere (12-27 km). Minimum ozone values concentration in the 20-27 km layer are found in November 2008. Mean 2008 December 12-20 km partial column remained below 40 DU, lower by 35% than the 2000-2005 mean. We present the relationship between the potential vorticity, timing of the vortex breakup date, the strength of the vortex and ozone concentration at different levels in an attempt to find dynamical features responsible for the observed behavior.

  6. Precision ozone calibration system based on vapor pressures of ozone

    NASA Technical Reports Server (NTRS)

    Mauersberger, K.; Hanson, D.; Morton, J.

    1987-01-01

    A precision ozone calibration system for stratospheric research has been developed and evaluated. Vapor pressures above solid ozone are mixed with a carrier gas (N2) to produce stratospheric ozone mixing ratios at total pressures of 1 to cover 20 torr. The uncertainty in the ozone mixing ratios is approximately + or - 1.5 percent, the stability of ozone is + or - 0.3 percent. Experiments to be calibrated may sample the gas mixture over a wide range of flow rates; the maximum throughput of gas with corrections of less than 1 percent to ozone is about 200 torr 1/min. A mass spectrometer system continuously monitors the purity and stability of the N2-O3 gas mixture.

  7. Analysis of atmospheric ozone measurements made from a B-747 airliner during March 1975

    NASA Technical Reports Server (NTRS)

    Holdeman, J. D.; Falconer, P. D.

    1976-01-01

    Measurements of atmospheric ozone in the upper troposphere and lower stratosphere made during March 1975 as part of the NASA Global Atmospheric Sampling Program are reported and analyzed. The interrelationships between the ozone mixing ratio and geographical and meteorological parameters are examined in several case studies. The ozone data correlate well with the difference between the flight altitude and the height of the tropopause, as obtained from National Meteorological Center gridded data. The distribution of ozone mixing ratios with latitude at an altitude of 11 + or - 0.5 km shows a poleward increase and large variability at latitudes greater than 30 deg N in agreement with published mean ozone levels from the North American ozone sonde network.

  8. Upper Tropospheric Ozone Between Latitudes 60S and 60N Derived from Nimbus 7 TOMS/THIR Cloud Slicing

    NASA Technical Reports Server (NTRS)

    Ziemke, Jerald R.; Chandra, Sushil; Bhartia, P. K.

    2002-01-01

    This study evaluates the spatial distributions and seasonal cycles in upper tropospheric ozone (pressure range 200-500 hPa) from low to high latitudes (60S to 60N) derived from the satellite retrieval method called "Cloud Slicing." Cloud Slicing is a unique technique for determining ozone profile information in the troposphere by combining co-located measurements of cloud-top, pressure and above-cloud column ozone. For upper tropospheric ozone, co-located measurements of Nimbus 7 Total Ozone Mapping Spectrometer (TOMS) above-cloud column ozone, and Nimbus 7 Temperature Humidity Infrared Radiometer (THIR) cloud-top pressure during 1979-1984 were incorporated. In the tropics, upper tropospheric ozone shows year-round enhancement in the Atlantic region and evidence of a possible semiannual variability. Upper tropospheric ozone outside the tropics shows greatest abundance in winter and spring seasons in both hemispheres with largest seasonal and largest amounts in the NH. These characteristics are similar to lower stratospheric ozone. Comparisons of upper tropospheric column ozone with both stratospheric ozone and a proxy of lower stratospheric air mass (i.e., tropopause pressure) from National Centers for Environmental Prediction (NCEP) suggest that stratosphere-troposphere exchange (STE) may be a significant source for the seasonal variability of upper tropospheric ozone almost everywhere between 60S and 60N except in low latitudes around 10S to 25N where other sources (e.g., tropospheric transport, biomass burning, aerosol effects, lightning, etc.) may have a greater role.

  9. Inquiry Based Projects Using Student Ozone Measurements and the Status of Using Plants as Bio-Indicators

    NASA Astrophysics Data System (ADS)

    Ladd, I. H.; Fishman, J.; Pippin, M.; Sachs, S.; Skelly, J.; Chappelka, A.; Neufeld, H.; Burkey, K.

    2006-05-01

    Students around the world work cooperatively with their teachers and the scientific research community measuring local surface ozone levels using a hand-held optical scanner and ozone sensitive chemical strips. Through the GLOBE (Global Learning and Observations to Benefit the Environment) Program, students measuring local ozone levels are connected with the chemistry of the air they breathe and how human activity impacts air quality. Educational tools have been developed and correlated with the National Science and Mathematics Standards to facilitate integrating the study of surface ozone with core curriculum. Ozone air pollution has been identified as the major pollutant causing foliar injury to plants when they are exposed to concentrations of surface ozone. The inclusion of native and agricultural plants with measuring surface ozone provides an Earth system approach to understanding surface ozone. An implementation guide for investigating ozone induced foliar injury has been developed and field tested. The guide, Using Sensitive Plants as Bio-Indicators of Ozone Pollution, provides: the background information and protocol for implementing an "Ozone Garden" with native and agricultural plants; and, a unique opportunity to involve students in a project that will develop and increase their awareness of surface ozone air pollution and its impact on plants.

  10. Have primary emission reduction measures reduced ozone across Europe? An analysis of European rural background ozone trends 1996-2005

    NASA Astrophysics Data System (ADS)

    Wilson, R. C.; Fleming, Z. L.; Monks, P. S.; Clain, G.; Henne, S.; Konovalov, I. B.; Szopa, S.; Menut, L.

    2012-01-01

    National and European legislation over the past 20 yr, and the modernisation or removal of industrial sources, have significantly reduced European ozone precursor emissions. This study quantifies observed and modelled European ozone annual and seasonal linear trends from 158 harmonised rural background monitoring stations over a constant time period of a decade (1996-2005). Mean ozone concentrations are investigated, in addition to the ozone 5th percentiles as a measure of the baseline or background conditions, and the 95th percentiles that are representative of the peak concentration levels. This study aims to characterise and quantify surface European ozone concentrations and trends and assess the impact of the changing anthropogenic emission tracers on the observed and modelled trends. Significant (p<0.1) positive annual trends in ozone mean, 5th and 95th percentiles are observed at 54 %, 52 % and 45 % of sites respectively (85 sites, 82 sites and 71 sites). Spatially, sites in central and north-western Europe tend to display positive annual ozone trends in mean, 5th and 95th percentiles. Significant negative annual trends in ozone mean 5th and 95th percentiles are observed at 11 %, 12 % and 12 % of sites respectively (18 sites, 19 sites and 19 sites) which tend to be located in the eastern and south-western extremities of Europe. European-averaged annual trends have been calculated from the 158 sites in this study. Overall there is a net positive annual trend in observed ozone mean (0.16±0.02 ppbv yr-1 (2σ error)), 5th (0.13±0.02 ppbv yr-1) and 95th (0.16±0.03 ppbv yr-1) percentiles, representative of positive trends in mean, baseline and peak ozone. Assessing the sensitivity of the derived overall trends to the constituent years shows that the European heatwave year of 2003 has significant positive influence and 1998 the converse effect; demonstrating the masking effect of inter-annual variability on decadal based ozone trends. The European scale 3-D CTM

  11. [Ozone source apportionment at urban area during a typical photochemical pollution episode in the summer of 2013 in the Yangtze River Delta].

    PubMed

    Li, Hao; Li, Li; Huang, Cheng; An, Jing-yu; Yan, Ru-sha; Huang, Hai-ying; Wang, Yang-jun; Lu, Qing; Wang, Qian; Lou, Sheng-rong; Wang, Hong-li; Zhou, Min; Tao, Shi-kang; Qiao, Li-ping; Chen, Ming-hua

    2015-01-01

    With the fast development of urbanization, industrialization and mobilization, the air pollutant emissions with photochemical reactivity become more obvious, causing a severe photochemical pollution with the characteristics of high ozone concentration. However, the ozone source identification is very complicated due to the high non linearity between ozone and its precursors. Thus, ways to reduce ozone is still not clear. A high ozone pollution episode occurred during July, 2013, which lasted for a long period, with large influence area and high intensity. In this paper, we selected this episode to do a case study with the application of ozone source apportionment technology(OSAT) coupled within the CAMx air quality model. In this study, 4 source regions(including Shanghai, north Zhejiang, South Jiangsu and long range transport), 7 source categories (including power plants, industrial process, industrial boilers and kilns, residential, mobile source, volatile source and biogenic emissions) are analyzed to study their contributions to surface O3 in Shanghai, Suzhou and Zhejiang. Results indicate that long range transport contribution to the surface ozone in the YRD is around 20 x 10(-9) - 40 x 10(-9) (volume fraction). The O3 concentrations can increased to 40 x 10(-9) - 100 x 10(-9) (volume fraction) due to precursors emissions in Shanghai, Jiangsu and Zhejiang. As for the regional contribution to 8 hour ozone, long range transport constitutes 42.79% +/- 10.17%, 48.57% +/- 9.97% and 60.13% +/- 7.11% of the surface ozone in Shanghai, Suzhou and Hangzhou, respectively. Regarding the high O3 in Shanghai, local contribution is 28.94% +/- 8.49%, north Zhejiang constitutes 19.83% +/- 10.55%. As for surface O3 in Suzhou, the contribution from south Jiangsu is 26.41% +/- 6.80%. Regarding the surface O3 in Hangzhou, the major regional contributor is north Zhejiang (29.56% +/- 8.33%). Contributions from the long range transport to the daily maximum O3 concentrations are

  12. [Ozone source apportionment at urban area during a typical photochemical pollution episode in the summer of 2013 in the Yangtze River Delta].

    PubMed

    Li, Hao; Li, Li; Huang, Cheng; An, Jing-yu; Yan, Ru-sha; Huang, Hai-ying; Wang, Yang-jun; Lu, Qing; Wang, Qian; Lou, Sheng-rong; Wang, Hong-li; Zhou, Min; Tao, Shi-kang; Qiao, Li-ping; Chen, Ming-hua

    2015-01-01

    With the fast development of urbanization, industrialization and mobilization, the air pollutant emissions with photochemical reactivity become more obvious, causing a severe photochemical pollution with the characteristics of high ozone concentration. However, the ozone source identification is very complicated due to the high non linearity between ozone and its precursors. Thus, ways to reduce ozone is still not clear. A high ozone pollution episode occurred during July, 2013, which lasted for a long period, with large influence area and high intensity. In this paper, we selected this episode to do a case study with the application of ozone source apportionment technology(OSAT) coupled within the CAMx air quality model. In this study, 4 source regions(including Shanghai, north Zhejiang, South Jiangsu and long range transport), 7 source categories (including power plants, industrial process, industrial boilers and kilns, residential, mobile source, volatile source and biogenic emissions) are analyzed to study their contributions to surface O3 in Shanghai, Suzhou and Zhejiang. Results indicate that long range transport contribution to the surface ozone in the YRD is around 20 x 10(-9) - 40 x 10(-9) (volume fraction). The O3 concentrations can increased to 40 x 10(-9) - 100 x 10(-9) (volume fraction) due to precursors emissions in Shanghai, Jiangsu and Zhejiang. As for the regional contribution to 8 hour ozone, long range transport constitutes 42.79% +/- 10.17%, 48.57% +/- 9.97% and 60.13% +/- 7.11% of the surface ozone in Shanghai, Suzhou and Hangzhou, respectively. Regarding the high O3 in Shanghai, local contribution is 28.94% +/- 8.49%, north Zhejiang constitutes 19.83% +/- 10.55%. As for surface O3 in Suzhou, the contribution from south Jiangsu is 26.41% +/- 6.80%. Regarding the surface O3 in Hangzhou, the major regional contributor is north Zhejiang (29.56% +/- 8.33%). Contributions from the long range transport to the daily maximum O3 concentrations are

  13. Ozone and ozone byproducts in the cabins of commercial aircraft.

    PubMed

    Weisel, Clifford; Weschler, Charles J; Mohan, Kris; Vallarino, Jose; Spengler, John D

    2013-05-01

    The aircraft cabin represents a unique indoor environment due to its high surface-to-volume ratio, high occupant density, and the potential for high ozone concentrations at cruising altitudes. Ozone was continuously measured and air was sampled on sorbent traps, targeting carbonyl compounds, on 52 transcontinental U.S. or international flights between 2008 and 2010. The sampling was predominantly on planes that did not have ozone scrubbers (catalytic converters). Peak ozone levels on aircraft without catalytic convertors exceeded 100 ppb, with some flights having periods of more than an hour when the ozone levels were >75 ppb. Ozone was greatly reduced on relatively new aircraft with catalytic convertors, but ozone levels on two flights whose aircraft had older convertors were similar to those on planes without catalytic convertors. Hexanal, heptanal, octanal, nonanal, decanal, and 6-methyl-5-hepten-2-one (6-MHO) were detected in the aircraft cabin at sub- to low ppb levels. Linear regression models that included the log transformed mean ozone concentration, percent occupancy, and plane type were statistically significant and explained between 18 and 25% of the variance in the mixing ratio of these carbonyls. Occupancy was also a significant factor for 6-MHO, but not the linear aldehydes, consistent with 6-MHO's formation from the reaction between ozone and squalene, which is present in human skin oils. PMID:23517299

  14. Analysis of the Suitability of OMPS LP Ozone Profile Dataset for Extending the Aura MLS Record

    NASA Astrophysics Data System (ADS)

    Kramarova, N. A.; Bhartia, P. K.; Stolarski, R. S.; DeLand, M. T.

    2014-12-01

    The new Ozone Mapping and Profiler Suite (OMPS), launched on 28 October 2011 on the Suomi National Polar-orbiting Partnership satellite, represents the next generation of the US ozone monitoring system. The OMPS Limb Profiler (LP) sensor measures solar radiances scattered from the atmospheric limb in the UV and visible spectral ranges and reconstruct the vertical ozone profiles from the cloud top up to 60 km. The regular LP observations started in early 2012, and now the LP data record exceeds 2.5 years. In this presentation we will demonstrate capability of the new LP sensor to characterize the vertical ozone distribution in different atmospheric regions that are most sensitive to the changes in the stratospheric composition and dynamics. We will consider: a) the seasonal ozone patterns in the lower stratosphere - upper troposphere; b) the vertical ozone distribution inside the Antarctic ozone hole; c) the ozone patterns forced by the Quasi-Biennial Oscillations in the lower tropical stratosphere. The main focus of this study is to perform a comprehensive analysis of ozone patterns obtained from OMPS LP with those observed by Aura MLS to isolate similarities and differences between two sensors in characterizing these processes. We will examine how well LP reproduces the named above natural signals in comparison with MLS in terms of amplitude, phase and vertical structure. One of the key issues is that two instruments measure ozone in different coordinate systems: the LP measures ozone profiles as number density on a regular altitude scale, while Aura MLS retrieves ozone profiles as mixing ratios on pressure vertical grids. The comparison of two measurements requires unit conversion that in turn involves temperature profiles. Thus, the uncertainties related to the unit conversion should be accounted during the analysis. This scientific validation is critical for the further LP algorithm improvement and continuation of the Aura MLS ozone record in the future.

  15. Degradation of carbofuran by ozonation.

    PubMed

    Suneethi, S; Joseph, Kurian

    2009-04-01

    Degradation of commercial grade carbofuran (2, 3 dihydro-2, 2-dimethyl-7 benzo furanyl-N-methyl carbamate) in aqueous solution by ozone oxidation was investigated using bench scale experiments. The degradation rate was strongly influenced by the ozone dosage, pH, initial concentration of carbofuran and contact time of ozonation. Carbofuran solution of 200ppm concentration was degraded by 79% within 10 minutes consuming 87 mg of ozone at pH 4. The associated TOC reduction was observed to be 53%. Ammonium (20 mg/L) and nitrate (30 mg/L) ions were detected in the effluent as degradation products of ozonation. The results support the effectiveness of ozonation for degradation of organic pesticides such as carbofuran.

  16. The role of refinery flaring events and bay breezes on a high surface ozone episode during the Houston, Texas DISCOVER-AQ field campaign

    NASA Astrophysics Data System (ADS)

    Loughner, C.; Follette-Cook, M. B.; Fried, A.; Pickering, K. E.

    2015-12-01

    The highest observed surface ozone concentrations in the Houston metropolitan area in 2013 occurred on September 25, which coincided with the Texas DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign. Surface ozone was elevated throughout the Houston metropolitan area with maximum 8-hour average ozone peaking along the western shore of Galveston Bay, reaching 124 ppbv, almost 50 ppbv above the current EPA standard of 75 ppbv. The NASA P-3B aircraft observed plumes from refinery flares west and northwest of Galveston Bay that were transported over the water. Continental air pollution from the north was transported into the Houston metropolitan area where it mixed with locally generated emissions. A bay breeze circulation formed causing pollutants that were transported out over the water in the morning to recirculate back inland where they mixed with freshly emitted pollution near the bay breeze convergence zone. The highest surface ozone concentrations were reported near the bay breeze front. This ozone episode will be presented using measurements made during the DISCOVER-AQ field campaign and a CMAQ model simulation with integrated source apportionment, which tracks the contribution of emissions source groups and regions on ozone concentrations.

  17. Ozonated olive oils and the troubles.

    PubMed

    Uysal, Bulent

    2014-01-01

    One of the commonly used methods for ozone therapy is ozonated oils. Most prominent type of used oils is extra virgin olive oil. But still, each type of unsaturated oils may be used for ozonation. There are a lot of wrong knowledge on the internet about ozonated oils and its use as well. Just like other ozone therapy studies, also the studies about ozone oils are inadequate to avoid incorrect knowledge. Current data about ozone oil and its benefits are produced by supplier who oversees financial interests and make misinformation. Despite the rapidly increasing ozone oil sales through the internet, its quality and efficacy is still controversial. Dozens of companies and web sites may be easily found to buy ozonated oil. But, very few of these products are reliable, and contain sufficiently ozonated oil. This article aimed to introduce the troubles about ozonated oils and so to inform ozonated oil users. PMID:26401346

  18. Ozone, Air Quality, and Asthma (For Parents)

    MedlinePlus

    ... found in both the Earth's upper and lower atmospheres. The protective ozone in the upper atmosphere is very different from the harmful ozone in the lower atmosphere. Ozone that exists naturally 10 to 30 miles ( ...

  19. Intercomparison of stratospheric ozone and temperature profiles during the October 2005 Hohenpeissenberg Ozone Profiling Experiment (HOPE)

    NASA Astrophysics Data System (ADS)

    Steinbrecht, W.; McGee, T. J.; Twigg, L. W.; Claude, H.; Schönenborn, F.; Sumnicht, G. K.; Silbert, D.

    2009-01-01

    Thirteen clear nights in October 2005 allowed successful intercomparison of the stationary lidar operated since 1987 by the German Weather Service (DWD) at Hohenpeissenberg (47.8° N, 11.0° E) with the Network for the Detection of Atmospheric Composition Change (NDACC) travelling standard lidar operated by NASA's Goddard Space Flight Center. Both lidars provide ozone profiles in the stratosphere, and temperature profiles in the strato- and mesosphere. Additional ozone profiles came from on-site Brewer/Mast ozonesondes, additional temperature profiles from Vaisala RS92 radiosondes launched at Munich (65 km north-east), and from operational analyses by the US National Centers for Environmental Prediction (NCEP). The intercomparison confirmed a low bias for ozone from the DWD lidar in the 33 to 43 km region, by up to 10%. This bias is caused by the DWD ozone algorithm. It will be removed in a future version. Between 20 and 33 km, agreement between both lidars, and ozonesondes below 30 km, is good with ozone differences less than 3 to 5%. Results are consistent with previous comparisons of the DWD lidar with SAGE, GOMOS and other satellite instruments. The intercomparison did uncover a 290 m upward shift of the DWD lidar data. When this shift is removed, agreement with ozone from the NASA lidar improves below 20 km, with remaining differences usually less than 5%, and not statistically significant. Precision (repeatability) for the lidar ozone data is better than 5% between 20 and 40 km altitude, dropping to 10% near 45 km, and 50% near 50 km. Temperature from the DWD lidar has a 1 to 2 K cold bias from 30 to 65 km against the NASA lidar, and a 2 to 4 K cold bias against radiosondes and NCEP. This is consistent with previous intercomparisons against NCEP or radiosondes. The cold bias against the NASA lidar disappears when the DWD lidar data are corrected for the afore-mentioned 290 m range error, and more appropriate values for the Earth's gravity acceleration are

  20. Protecting beans from ozone

    SciTech Connect

    Pierce, R.

    1983-03-01

    A chemical treatment to protect navy beans from ozone damage increased yields by an average of more than 20% in 3 years of tests. An experimental antioxidant chemical, EDU, made by the DuPont company was tested as soil applications and sprays on several varieties and under a variety of soil and planting conditions. The average yield increases were between 16 and 24%. Chemical treatment also increased snap bean pod production by 12%.

  1. Ozone attainment: A different perspective

    SciTech Connect

    Beck, W.B. )

    1988-01-01

    Recent attention on the ozone non-attainment issue has been focused on Washington. Both Congress and the EPA have made efforts at addressing the post-1987 crisis in the many non-attainment areas. In contrast to the political activity, this paper presents some interesting technical perspectives on ozone attainment for many areas of the U.S.. Issues such as transport, climate and natural ozone sources are discussed in the context of exceedance frequency for several geographical areas of the country.

  2. Alternative ozone metrics and daily mortality in Suzhou: the China Air Pollution and Health Effects Study (CAPES).

    PubMed

    Yang, Chunxue; Yang, Haibing; Guo, Shu; Wang, Zongshuang; Xu, Xiaohui; Duan, Xiaoli; Kan, Haidong

    2012-06-01

    Controversy remains regarding the relationship between various metrics of ozone (O(3)) and mortality. In China, the largest developing country, there have been few studies investigating the acute effect of O(3) on death. We used three exposure metrics of O(3) (1-hour maximum, maximum 8-hour average and 24-hour average) to examine its short-term association with daily mortality in Suzhou, China. We used a Generalized Additive Model (GAM) with penalized splines to analyze the mortality, O(3), and covariate data. We examined the association by season, age group, sex and educational level. We found that the current level of O(3) in Suzhou is associated with death rates from all causes and cardiovascular diseases. Among various metrics of O(3), maximum 8-hour average and 1-hour maximum concentrations seem to be more strongly associated with increased mortality rate compared to 24-hour average concentrations. Using maximum 8-hour average, an inter-quartile range increase of 2-day average O(3) (lag 01) corresponds to 2.15% (95%CI, 0.36 to 3.93), 4.47% (95%CI, 1.43 to 7.51), -1.85% (95%CI, -6.91 to 3.22) increase in all-cause, cardiovascular, and respiratory mortality, respectively. The associations between O(3) and daily mortality appeared to be more evident in the cool season than in the warm season. In conclusion, maximum 8-hour average and 1-hour maximum concentrations of O(3) are associated with daily mortality in Suzhou. Our analyses strengthen the rationale for further limiting levels of O(3) pollution in the city. PMID:22521098

  3. Ozone transport commission developments

    SciTech Connect

    Joyce, K.M.

    1995-08-01

    On September 27, 1994, the states of the Ozone Transport Commission (OTC) signed an important memorandum of understanding (MOU) agreeing to develop a regional strategy for controlling stationary sources of nitrogen oxide emissions. Specifically, the states of the Ozone Transport Region, OTR, agreed to propose regulations for the control of NOx emissions from boilers and other indirect heat exchangers with a maximum gross heat input rate of at least 250 million BTU per hour. The Ozone Transport Region was divided into Inner, Outer and Northern Zones. States in the Outer Zone agreed to reduce NOx emissions by 55%. States in the Inner Zone agreed to reduce NOx emissions 65%. Facilities in both zones have the option to emit NOx at a rate no greater than 0.2 pounds per million Btu by May 1, 1999. This option provides fairness for the gas-fired plants which already have relatively low NOx emissions. Additionally, States in the Inner and Outer Zones agreed to reduce their NOx emissions by 75% or to emit NOx at a rate no greater than 0.15 pounds per million BTU by May 1, 2003. The Northern Zone States agree to reduce their rate of NOx emissions by 55% from base year levels by May 1, 2003, or to emit NOx at a rate no greater than 0.2 pounds per million BTU. As part of this MOU, States also agreed to develop a regionwide trading mechanism to provide a cost-effective mechanism for implementing the reductions.

  4. Ozone measurement systems improvements studies

    NASA Technical Reports Server (NTRS)

    Thomas, R. W.; Guard, K.; Holland, A. C.; Spurling, J. F.

    1974-01-01

    Results are summarized of an initial study of techniques for measuring atmospheric ozone, carried out as the first phase of a program to improve ozone measurement techniques. The study concentrated on two measurement systems, the electro chemical cell (ECC) ozonesonde and the Dobson ozone spectrophotometer, and consisted of two tasks. The first task consisted of error modeling and system error analysis of the two measurement systems. Under the second task a Monte-Carlo model of the Dobson ozone measurement technique was developed and programmed for computer operation.

  5. Aerosol Correction for Improving OMPS/LP Ozone Retrieval

    NASA Technical Reports Server (NTRS)

    Chen, Zhong; Bhartia, Pawan K.; Loughman, Robert

    2015-01-01

    The Ozone Mapping and Profiler Suite Limb Profiler (OMPS-LP) on board the Suomi National Polar-orbiting Partnership (SNPP) satellite was launched on Oct. 28, 2011. Limb profilers measures the radiance scattered from the Earth's atmospheric in limb viewing mode from 290 to 1000 nm and infer ozone profiles from tropopause to 60 km. The recently released OMPS-LP Version 2 data product contains the first publicly released ozone profiles retrievals, and these are now available for the entire OMPS mission, which extends from April, 2012. The Version 2 data product retrievals incorporate several important improvements to the algorithm. One of the primary changes is to turn off the aerosol retrieval module. The aerosol profiles retrieved inside the ozone code was not helping the ozone retrieval and was adding noise and other artifacts. Aerosols including polar stratospheric cloud (PSC) and polar mesospheric clouds (PMC) have a detectable effect on OMPS-LP data. Our results show that ignoring the aerosol contribution would produce an ozone density bias of up to 10 percent in the region of maximum aerosol extinction. Therefore, aerosol correction is needed to improve the quality of the retrieved ozone concentration profile. We provide Aerosol Scattering Index (ASI) for detecting aerosols-PMC-PSC, defined as ln(Im-Ic) normalized at 45km, where Im is the measured radiance and Ic is the calculated radiance assuming no aerosols. Since ASI varies with wavelengths, latitude and altitude, we can start by assuming no aerosol profiles in calculating the ASIs and then use the aerosol profile to see if it significantly reduces the residuals. We also discuss the effect of aerosol size distribution on the ozone profile retrieval process. Finally, we present an aerosol-PMC-PSC correction scheme.

  6. Use of computer-simulated radiances to retrieve total atmospheric ozone data from satellite-mounted infrared multifilter radiometers

    SciTech Connect

    Weidhaas, P.P.

    1980-10-01

    Between March 1977 and February 1980, four satellites equipped with multichannel filter radiometer (MFR) sensors supplied infrared radiance data at various spectral channels. The Satellite Ozone Analysis Center (SOAC) at the Lawrence Livermore National Laboratory received the radiance data from the US Air Force. An ozone retrieval model was developed by SOAC in order to derive total ozone values from the radiance data. Statistical comparison against a network of ground observatories which measure total ozone with a Dobson spectrophotometer showed good agreement between MFR-derived ozone data and Dobson measurements. Thus, the scientific feasibility of SOAC's ozone retrieval model was established. Currently, SOAC has begun to automate the processing and archiving of the MFR data. Daily computer-generated contour maps of the global ozone distribution will be produced for dissemination to the scientific community. Extensive data analysis is also in progress.

  7. Have primary emission reduction measures reduced ozone across Europe? An analysis of European rural background ozone trends 1996-2005

    NASA Astrophysics Data System (ADS)

    Wilson, R. C.; Fleming, Z. L.; Monks, P. S.; Clain, G.; Henne, S.; Konovalov, I. B.; Szopa, S.; Menut, L.

    2011-06-01

    National and European legislation over the past 20 years, and the modernisation or removal of industrial sources, have significantly reduced European ozone precursor emissions. This study quantifies observed and modelled European ozone annual and seasonal linear trends from 158 harmonised rural background monitoring stations over a constant time period of a decade (1996-2005). Mean ozone concentrations are investigated, in addition to the ozone 5th percentiles as a measure of the baseline or background conditions, and the 95th percentiles that are representative of the peak concentration levels. This study aims to characterise and quantify surface European ozone concentrations and trends and assess the impact of the changing anthropogenic emission tracers on the observed and modelled trends. Significant (p < 0.1) positive annual trends in ozone mean, 5th and 95th percentiles are observed at 54 %, 52 % and 45 % of sites respectively (85 sites, 82 sites and 71 sites). Spatially, sites in Central and Northwestern Europe tend to display positive annual ozone trends in mean, 5th and 95th percentiles. Significant negative annual trends in ozone mean 5th and 95th percentiles are observed at 11 %, 12 % and 12 % of sites respectively (18 sites, 19 sites and 19 sites) which tend to be located in the eastern and south-western extremities of Europe. European-averaged annual trends have been calculated from the 158 sites in this study. Overall there is a net positive annual trend in observed ozone mean (0.16 ± 0.02 ppbv yr-1 2σ error)), 5th (0.13 ± 0.02 ppbv yr-1) and 95th (0.16 ± 0.03 ppbv yr-1) percentiles, representative of positive trends in mean, baseline and peak ozone. Assessing the sensitivity of the derived overall trends to the constituent years shows that the European heatwave year of 2003 has significant positive influence and 1998 the converse effect; demonstrating the masking effect of inter-annual variability on decadal based ozone trends. The European scale

  8. Ozone Depletion, Greenhouse Gases, and Climate Change. Proceedings of a Joint Symposium by the Board on Atmospheric Sciences and Climate and the Committee on Global Change, National Research Council (Washington, D.C., March 23, 1988).

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC.

    The motivation for the organization of this symposium was the accumulation of evidence from many sources, both short- and long-term, that the global climate is in a state of change. Data which defy integrated explanation including temperature, ozone, methane, precipitation and other climate-related trends have presented troubling problems for…

  9. Comparison of satellite measurements of ozone and ozone trends

    SciTech Connect

    Rusch, D.W.; Clancy, R.T.; Bhartia, P.K. |

    1994-10-01

    Measurements of ozone retrieved from satellite instruments over the 1979-1991 period are compared. The instruments used are the total ozone mapping spectrometer (TOMS), the solar backscattered ultraviolet experiment (SBUV), and stratospheric aerosol and gas experiments (SAGE) I and II. Although there is good agreement between the absolute densities of ozone as measured by the various instruments, the long-term changes (1979-1990) disagree sharply as a function of pressure and in the integrated ozone amount. In the upper stratosphere, SBUV trends are negative with maximum values of about -1.5%/year at high latitudes. Combined SAGE I and II trends are slightly positive in this region and peak near 0.5%/year at equatorial latitudes. In the lower stratosphere, SBUV trends reflect small decreases in ozone, generally less than -0.4%/year except at high southern latitudes where the trends rearch values of approximately -1.5%/year. SAGE ozone trends exhibit large decreases particularly in the equatorial regions where decreases of 3-6%/year are seen at pressures between 60 and 90 mbar. At higher latitudes, SAGE trends are more comparable to SBUV trends in the lower stratosphere. Total ozone trends from TOMS and SBUV agree within their uncertainties. Near-zero trends are indicated at low latitudes, and larger, negative trends (approximately -0.5%/year) are indicated near the poles. The SAGE column ozone trends depend upon the base level altitude of integration but do not exhibit a strong latitude dependence.

  10. Ultraviolet Radiation and Stratospheric Ozone

    NASA Technical Reports Server (NTRS)

    Stolarski, R.

    2003-01-01

    Ultraviolet radiation from the sun produces ozone in the stratosphere and it participates in the destruction of ozone. Absorption of solar ultraviolet radiation by ozone is the primary heating mechanism leading to the maximum in temperature at the stratopause. Variations of solar ultraviolet radiation on both the 27-day solar rotation period and the 11-year solar cycle affect ozone by several mechanisms. The temperature and ozone in the upper stratosphere respond to solar uv variations as a coupled system. An increase in uv leads to an increase in the production of ozone through the photolysis of molecular oxygen. An increase in uv leads to an increase in temperature through the heating by ozone photolysis. The increase in temperature leads to a partially-offsetting decrease in ozone through temperature-dependent reaction rate coefficients. The ozone variation modulates the heating by ozone photolysis. The increase in ozone at solar maximum enhances the uv heating. The processes are understood and supported by long-term data sets. Variation in the upper stratospheric temperatures will lead to a change in the behavior of waves propagating upward from the troposphere. Changes in the pattern of wave dissipation will lead to acceleration or deceleration of the mean flow and changes in the residual or transport circulation. This mechanism could lead to the propagation of the solar cycle uv variation from the upper stratosphere downward to the lower stratosphere. This process is not well-understood and has been the subject of an increasing number of model studies. I will review the data analyses for solar cycle and their comparison to model results.

  11. A Transport Analysis of In Situ Airborne Ozone Measurements from the 2011 DISCOVER-AQ Campaign

    NASA Astrophysics Data System (ADS)

    Arkinson, H. L.; Brent, L. C.; He, H.; Loughner, C.; Stehr, J. W.; Weinheimer, A. J.; Dickerson, R. R.

    2013-12-01

    Baltimore and Washington are currently designated as nonattainment areas with respect to the 2008 EPA National Ambient Air Quality Standard (NAAQS) for 8-hour Ozone (O3). Tropospheric O3 is the dominant component of summertime photochemical smog, and at high levels, has deleterious effects on human health, ecosystems, and materials. The University of Maryland (UMD) Regional Atmospheric Measurement Modeling and Prediction Program (RAMMPP) strives to improve understanding of air quality in the Mid-Atlantic States and to elucidate contributions of pollutants such as O3 from regional transport versus local sources through a combination of modeling and in situ measurements. The NASA Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) project investigates the connection between column measurements and surface conditions to explore the potential of remote sensing observations in diagnosing air quality at ground level where pollutants can affect human health. During the 2011 DISCOVER-AQ field campaign, in situ airborne measurements of trace gases and aerosols were performed along the Interstate 95 corridor between Baltimore and Washington from the NASA P3B aircraft. To augment this data and provide regional context, measurements of trace gases and aerosols were also performed by the RAMMPP Cessna 402B aircraft over nearby airports in Maryland and Virginia. This work presents an analysis of O3 measurements made by the Ultraviolet (UV) Photometric Ambient O3 Analyzer on the RAMMPP Cessna 402B and by the NCAR 4-Channel Chemiluminescence instrument on the NASA P3B. In this analysis, spatial and temporal patterns of O3 data are examined within the context of forward and backward trajectories calculated from 12-km North American Mesoscale (NAM) meteorological data using the NOAA Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) Model and from a high resolution Weather Research and

  12. Background ozone over the United States in summer: Origin, trend, and contribution to pollution episodes

    NASA Astrophysics Data System (ADS)

    Fiore, Arlene M.; Jacob, Daniel J.; Bey, Isabelle; Yantosca, Robert M.; Field, Brendan D.; Fusco, Andrew C.; Wilkinson, James G.

    2002-08-01

    Observations indicate that ozone (O3) concentrations in surface air over the United States in summer contain a 20-45 ppbv background contribution, presumably reflecting transport from outside the North American boundary layer. We use a three-dimensional global model of tropospheric chemistry driven by assimilated meteorological observations to investigate the origin of this background and to quantify its contribution to total surface O3 on both average and highly polluted summer days. The model simulation is evaluated with a suite of surface and aircraft observations over the United States from the summer of 1995. The model reproduces the principal features in the observed distributions of O3 and its precursors, including frequency distributions of O3 concentrations and the development of regional high-O3 episodes in the eastern United States. Comparison of simulations with 1995 versus 1980 global fossil fuel emissions indicates that the model captures the previously observed decrease in the high end of the O3 probability distribution in surface air over the United States (reflecting reduction of domestic hydrocarbon emissions) and the increase in the low end (reflecting, at least in the model, rising Asian emissions). In the model, background O3 produced outside of the North American boundary layer contributes an average 25-35 ppbv to afternoon O3 concentrations in surface air in the western United States. and 15-30 ppbv in the eastern United States during the summer of 1995. This background generally decays to below 15 ppbv during the stagnation conditions conducive to exceedances of the 8-hour 0.08 ppmv (80 ppbv) National Ambient Air Quality Standard (NAAQS) for O3. A high background contribution of 25-40 ppbv is found during 9% of these exceedances, reflecting convective mixing of free tropospheric O3 from aloft, followed by rapid production within the U.S. boundary layer. Anthropogenic emissions in Asia and Europe are found to increase afternoon O3

  13. Springtime high surface ozone events over the western United States: Quantifying the role of stratospheric intrusions

    NASA Astrophysics Data System (ADS)

    Fiore, A. M.; Lin, M.; Cooper, O. R.; Horowitz, L. W.; Naik, V.; Levy, H.; Langford, A. O.; Johnson, B. J.; Oltmans, S. J.; Senff, C. J.

    2011-12-01

    As the National Ambient Air Quality (NAAQS) standard for ozone (O_{3}) is lowered, it pushes closer to policy-relevant background levels (O_{3} concentrations that would exist in the absence of North American anthropogenic emissions), making attainment more difficult with local controls. We quantify the Asian and stratospheric components of this North American background, with a primary focus on the western United States. Prior work has identified this region as a hotspot for deep stratospheric intrusions in spring. We conduct global simulations at 200 km and 50 km horizontal resolution with the GFDL AM3 model, including a stratospheric O_{3} tracer and two sensitivity simulations with anthropogenic emissions from Asia and North America turned off. The model is evaluated with a suite of in situ and satellite measurements during the NOAA CalNex campaign (May-June 2010). The model reproduces the principle features in the observed surface to near tropopause distribution of O_{3} along the California coast, including its latitudinal variation and the development of regional high-O_{3} episodes. Four deep tropopause folds are diagnosed and we find that the remnants of these stratospheric intrusions are transported to the surface of Southern California and Western U.S. Rocky Mountains, contributing 10-30 ppbv positive anomalies relative to the simulated campaign mean stratospheric component in the model surface layer. We further examine the contribution of North American background, including its stratospheric and Asian components, to the entire distribution of observed MDA8 O_{3} at 12 high-elevation CASTNet sites in the Mountain West. We find that the stratospheric O_{3} tracer constitutes 50% of the North American background, and can enhance surface maximum daily 8-hour average (MDA8) O_{3} by 20 ppb when observed surface O_{3} is in the range of 60-80 ppbv. Our analysis highlights the potential for natural sources such as deep stratospheric intrusions to contribute

  14. An analysis of the trend in ground-level ozone using non-homogeneous poisson processes

    NASA Astrophysics Data System (ADS)

    Shively, Thomas S.

    This paper provides a method for measuring the long-term trend in the frequency with which ground-level ozone present in the ambient air exceeds the U.S. Environmental Protection Agency's National Ambient Air Quality Standard (NAAQS) for ozone. A major weakness of previous studies that estimate the long-term trend in the very high values of ozone, and therefore the long-term trend in the probability of satisfying the NAAQS for ozone, is their failure to account for the confounding effects of meterological conditions on ozone levels. Meteorological variables such as temperature, wind speed, and frontal passage play an important role in the formation of ground-level ozone. A non-homogenous Poisson process is used to account for the relationship between very high values of ozone and meteorological conditions. This model provides an estimate of the trend in the ozone values after allowing for the effects of meteorological conditions. Therefore, this model provides a means to measure the effectiveness of pollution control programs after accounting for the effects of changing weather conditions. When our approach is applied to data collected at two sites in Houston, TX, we find evidence of a gradual long-term downward trend in the frequency of high values of ozone. The empirical results indicate how possibly misleading results can be obtained if the analysis does not account for changing weather conditions.

  15. Magnetic resonance diffusion tensor imaging following major ozonated autohemotherapy for treatment of acute cerebral infarction.

    PubMed

    Wu, Xiao-Na; Zhang, Tao; Wang, Jun; Liu, Xiao-Yan; Li, Zhen-Sheng; Xiang, Wei; Du, Wei-Qing; Yang, Hong-Jun; Xiong, Tie-Gen; Deng, Wen-Ting; Peng, Kai-Run; Pan, Su-Yue

    2016-07-01

    Major ozonated autohemotherapy has been shown to promote recovery of upper limb motor function in patients with acute cerebral infarction, but whether major ozonated autohemotherapy affects remote injury remains poorly understood. Here, we assumed that major ozonated autohemotherapy contributes to recovery of clinical function, possibly by reducing remote injury after acute cerebral infarction. Sixty acute cerebral infarction patients aged 30-80 years were equally and randomly allocated to ozone treatment and control groups. Patients in the ozone treatment group received medical treatment and major ozonated autohemotherapy (47 mg/L, 100 mL ozone) for 10 ± 2 days. Patients in the control group received medical treatment only. National Institutes of Health Stroke Scale score, modified Rankin scale score, and reduced degree of fractional anisotropy values of brain magnetic resonance diffusion tensor imaging were remarkably decreased, brain function improved, clinical efficiency significantly increased, and no obvious adverse reactions detected in the ozone treatment group compared with the control group. These findings suggest that major ozonated autohemotherapy promotes recovery of neurological function in acute cerebral infarction patients by reducing remote injury, and additionally, exhibits high safety. PMID:27630695

  16. Magnetic resonance diffusion tensor imaging following major ozonated autohemotherapy for treatment of acute cerebral infarction

    PubMed Central

    Wu, Xiao-na; Zhang, Tao; Wang, Jun; Liu, Xiao-yan; Li, Zhen-sheng; Xiang, Wei; Du, Wei-qing; Yang, Hong-jun; Xiong, Tie-gen; Deng, Wen-ting; Peng, Kai-run; Pan, Su-yue

    2016-01-01

    Major ozonated autohemotherapy has been shown to promote recovery of upper limb motor function in patients with acute cerebral infarction, but whether major ozonated autohemotherapy affects remote injury remains poorly understood. Here, we assumed that major ozonated autohemotherapy contributes to recovery of clinical function, possibly by reducing remote injury after acute cerebral infarction. Sixty acute cerebral infarction patients aged 30–80 years were equally and randomly allocated to ozone treatment and control groups. Patients in the ozone treatment group received medical treatment and major ozonated autohemotherapy (47 mg/L, 100 mL ozone) for 10 ± 2 days. Patients in the control group received medical treatment only. National Institutes of Health Stroke Scale score, modified Rankin scale score, and reduced degree of fractional anisotropy values of brain magnetic resonance diffusion tensor imaging were remarkably decreased, brain function improved, clinical efficiency significantly increased, and no obvious adverse reactions detected in the ozone treatment group compared with the control group. These findings suggest that major ozonated autohemotherapy promotes recovery of neurological function in acute cerebral infarction patients by reducing remote injury, and additionally, exhibits high safety. PMID:27630695

  17. Unequivocal detection of ozone recovery in the Antarctic Ozone Hole through significant increases in atmospheric layers with minimum ozone

    NASA Astrophysics Data System (ADS)

    de Laat, Jos; van Weele, Michiel; van der A, Ronald

    2015-04-01

    An important new landmark in present day ozone research is presented through MLS satellite observations of significant ozone increases during the ozone hole season that are attributed unequivocally to declining ozone depleting substances. For many decades the Antarctic ozone hole has been the prime example of both the detrimental effects of human activities on our environment as well as how to construct effective and successful environmental policies. Nowadays atmospheric concentrations of ozone depleting substances are on the decline and first signs of recovery of stratospheric ozone and ozone in the Antarctic ozone hole have been observed. The claimed detection of significant recovery, however, is still subject of debate. In this talk we will discuss first current uncertainties in the assessment of ozone recovery in the Antarctic ozone hole by using multi-variate regression methods, and, secondly present an alternative approach to identify ozone hole recovery unequivocally. Even though multi-variate regression methods help to reduce uncertainties in estimates of ozone recovery, great care has to be taken in their application due to the existence of uncertainties and degrees of freedom in the choice of independent variables. We show that taking all uncertainties into account in the regressions the formal recovery of ozone in the Antarctic ozone hole cannot be established yet, though is likely before the end of the decade (before 2020). Rather than focusing on time and area averages of total ozone columns or ozone profiles, we argue that the time evolution of the probability distribution of vertically resolved ozone in the Antarctic ozone hole contains a better fingerprint for the detection of ozone recovery in the Antarctic ozone hole. The advantages of this method over more tradition methods of trend analyses based on spatio-temporal average ozone are discussed. The 10-year record of MLS satellite measurements of ozone in the Antarctic ozone hole shows a

  18. The effect of ozone associated with summertime photochemical smog on the frequency of asthma visits to hospital emergency departments

    SciTech Connect

    Cody, R.P. ); Weisel, C.P.; Lioy, P.J. Environmental and Occupational Health Sciences Institute, Piscataway, NJ ); Birnbaum, G. )

    1992-08-01

    A retrospective study using ambient ozone, temperature, and other environmental variables and their effect on the frequency of hospital visits for asthma was conducted in New Jersey, an area that often exceeds the allowable national standard for ozone. Data on emergency department visits for asthma, bronchitis, and finger wounds (a nonrespiratory control) were analyzed for the period May through August for 1988 and 1989. Asthma visits were correlated with temperature while the correlation between asthma visits and ozone concentration was nonsignificant. However, when temperature was controlled for in a multiple regression analysis, a highly significant relationship between asthma visits and ozone concentration was identified. Between 13 and 15% of the variability of the asthma visits and ozone concentration was identified. Between 13 and 15% of the variability of the asthma visits was explained in the regression model by temperature and ambient ozone levels. This association, when compared to similar studies in Canada, shows the contribution of ozone to asthma admissions to be stronger in areas with higher ozone concentrations. Thus, among regions with periodic accumulations of ozone in the ambient atmosphere, an exposure-response relationship may be discernible. This supports the need to attain air quality standards for ozone to protect individuals in the general population from the adverse health effects caused by ambient ozone exposure. 21 refs., 1 fig., 6 tabs.

  19. Plant responses to tropospheric ozone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tropospheric ozone is the second most abundant air pollutant and an important component of the global climate change. Over five decades of research on the phytotoxicity of ozone in model plants systems, crop plants and forest trees have provided some insight into the physiological, biochemical and m...

  20. Nonaqueous ozonation of vulcanized rubber

    SciTech Connect

    Serkiz, S.M.

    1999-12-07

    A process and resulting product are provided in which a solid particulate, such as vulcanized crumb rubber, has the surface functional groups oxidized by ozonation using a nonpolar solvent. The ozonation process renders the treated crumb rubber more suitable for use in new rubber formulations. As a result, larger loading levels of the treated crumb rubber can be used in new rubber mixtures.

  1. Rocket ozone sounding network data

    NASA Technical Reports Server (NTRS)

    Wright, D. U.; Krueger, A. J.; Foster, G. M.

    1979-01-01

    During the period March 1977 through May 1977, three regular monthly ozone profiles were measured at Wallops Flight Center and three regular monthly ozone profiles were measured at the Churchill Research Range. One additional flight was conducted at Wallops Flight Center in support of Nimbus 4 SBUV. Data results and flight profiles for the period covered are presented.

  2. Atmospheric iodine abates smog ozone.

    PubMed

    HAMILTON, W F; LEVINE, M; SIMON, E

    1963-04-12

    Traces of iodine in test samples of irradiated photochemical smog atmospheres either inhibit ozone formation or lower its concentration. Eye and respiratory irritation are reduced qualitatively. Iodine is more effective in suppressing ozone in a photochemical smog atmosphere than it is in purified air.

  3. Modelling the Antarctic ozone hole

    NASA Technical Reports Server (NTRS)

    Crutzen, P. J.; Bruhl, C.

    1988-01-01

    Researchers performed model calculations of the ozone depletions taking place in the Antarctic lower stratosphere. Making the assumption that odd nitrogen is frozen out on stratospheric haze particles, an analysis is given of how much homogeneous reactions can contribute to ozone loss during September-October. Comparisons with observations indicate the potential importance of reactions with HCl in the polar stratospheric cloud particles.

  4. Nonaqueous ozonation of vulcanized rubber

    DOEpatents

    Serkiz, Steven M.

    1999-01-01

    A process and resulting product is provided in which a solid particulate, such as vulcanized crumb rubber, has the surface functional groups oxidized by ozonation using a nonpolar solvent. The ozonation process renders the treated crumb rubber more suitable for use in new rubber formulations. As a result, larger loading levels of the treated crumb rubber can be used in new rubber mixtures.

  5. Rocket ozone sounding network data

    NASA Technical Reports Server (NTRS)

    Wright, D. U.; Krueger, A. J.; Foster, G. M.

    1978-01-01

    During the period December 1976 through February 1977, three regular monthly ozone profiles were measured at Wallops Flight Center, two special soundings were taken at Antigua, West Indies, and at the Churchill Research Range, monthly activities were initiated to establish stratospheric ozone climatology. This report presents the data results and flight profiles for the period covered.

  6. Simplified ozone detection by chemiluminescence

    NASA Technical Reports Server (NTRS)

    Conway, E. J.; Rogowski, R. S.; Richards, R. R.

    1977-01-01

    Ozone is detected by film coated with solid, such as rubrene, that reacts with ozone to degree proportional to concentration in sample gas. Gas flow is stopped, and film is heated to produce light (chemiluminescence) in proportion to amount of reacted material on sensor.

  7. Past Changes in the Vertical Distribution of Ozone Part 1: Measurement Techniques, Uncertainties and Availability

    NASA Technical Reports Server (NTRS)

    Hassler, B.; Petropavlovskikh, I.; Staehelin, J.; August, T.; Bhartia, P. K.; Clerbaux, C.; Degenstein, D.; Maziere, M. De; Dinelli, B. M.; Dudhia, A.; Dufour, G.; Frith, S. M.; Froidevaux, L.; Godin-Beekmann, S.; Granville, J.; Harris, N. R. P.; Hoppel, K.; Hubert, D.; Kasai, Y.; Kurylo, M. J.; Kyrola, E.; Lambert, J.-C.; Levelt, P. F.; McElroy, C. T.; McPeters, R. D.; Munro, R.; Nakajima, H.; Parrish, A.; Raspollini, P.; Remsberg, E. E.; Rosenlof, K. H.; Rozanov, A.; Sano, T.; Sasano, Y.; Shiotani, M.; Zawodny, J. M.

    2014-01-01

    Peak stratospheric chlorofluorocarbon (CFC) and other ozone depleting substance (ODS) concentrations were reached in the mid- to late 1990s. Detection and attribution of the expected recovery of the stratospheric ozone layer in an atmosphere with reduced ODSs as well as efforts to understand the evolution of stratospheric ozone in the presence of increasing greenhouse gases are key current research topics. These require a critical examination of the ozone changes with an accurate knowledge of the spatial (geographical and vertical) and temporal ozone response. For such an examination, it is vital that the quality of the measurements used be as high as possible and measurement uncertainties well quantified. In preparation for the 2014 United Nations Environment Programme (UNEP)/World Meteorological Organization (WMO) Scientific Assessment of Ozone Depletion, the SPARC/IO3C/IGACO-O3/NDACC (SI2N) Initiative was designed to study and document changes in the global ozone profile distribution. This requires assessing long-term ozone profile data sets in regards to measurement stability and uncertainty characteristics. The ultimate goal is to establish suitability for estimating long-term ozone trends to contribute to ozone recovery studies. Some of the data sets have been improved as part of this initiative with updated versions now available. This summary presents an overview of stratospheric ozone profile measurement data sets (ground and satellite based) available for ozone recovery studies. Here we document measurement techniques, spatial and temporal coverage, vertical resolution, native units and measurement uncertainties. In addition, the latest data versions are briefly described (including data version updates as well as detailing multiple retrievals when available for a given satellite instrument). Archive location information for each data set is also given.

  8. Past changes in the vertical distribution of ozone - Part 1: Measurement techniques, uncertainties and availability

    NASA Astrophysics Data System (ADS)

    Hassler, B.; Petropavlovskikh, I.; Staehelin, J.; August, T.; Bhartia, P. K.; Clerbaux, C.; Degenstein, D.; De Mazière, M.; Dinelli, B. M.; Dudhia, A.; Dufour, G.; Frith, S. M.; Froidevaux, L.; Godin-Beekmann, S.; Granville, J.; Harris, N. R. P.; Hoppel, K.; Hubert, D.; Kasai, Y.; Kurylo, M. J.; Kyrölä, E.; Lambert, J.-C.; Levelt, P. F.; McElroy, C. T.; McPeters, R. D.; Munro, R.; Nakajima, H.; Parrish, A.; Raspollini, P.; Remsberg, E. E.; Rosenlof, K. H.; Rozanov, A.; Sano, T.; Sasano, Y.; Shiotani, M.; Smit, H. G. J.; Stiller, G.; Tamminen, J.; Tarasick, D. W.; Urban, J.; van der A, R. J.; Veefkind, J. P.; Vigouroux, C.; von Clarmann, T.; von Savigny, C.; Walker, K. A.; Weber, M.; Wild, J.; Zawodny, J. M.

    2014-05-01

    Peak stratospheric chlorofluorocarbon (CFC) and other ozone depleting substance (ODS) concentrations were reached in the mid- to late 1990s. Detection and attribution of the expected recovery of the stratospheric ozone layer in an atmosphere with reduced ODSs as well as efforts to understand the evolution of stratospheric ozone in the presence of increasing greenhouse gases are key current research topics. These require a critical examination of the ozone changes with an accurate knowledge of the spatial (geographical and vertical) and temporal ozone response. For such an examination, it is vital that the quality of the measurements used be as high as possible and measurement uncertainties well quantified. In preparation for the 2014 United Nations Environment Programme (UNEP)/World Meteorological Organization (WMO) Scientific Assessment of Ozone Depletion, the SPARC/IO3C/IGACO-O3/NDACC (SI2N) Initiative was designed to study and document changes in the global ozone profile distribution. This requires assessing long-term ozone profile data sets in regards to measurement stability and uncertainty characteristics. The ultimate goal is to establish suitability for estimating long-term ozone trends to contribute to ozone recovery studies. Some of the data sets have been improved as part of this initiative with updated versions now available. This summary presents an overview of stratospheric ozone profile measurement data sets (ground and satellite based) available for ozone recovery studies. Here we document measurement techniques, spatial and temporal coverage, vertical resolution, native units and measurement uncertainties. In addition, the latest data versions are briefly described (including data version updates as well as detailing multiple retrievals when available for a given satellite instrument). Archive location information for each data set is also given.

  9. SI2N overview paper: ozone profile measurements: techniques, uncertainties and availability

    NASA Astrophysics Data System (ADS)

    Hassler, B.; Petropavlovskikh, I.; Staehelin, J.; August, T.; Bhartia, P. K.; Clerbaux, C.; Degenstein, D.; De Mazière, M.; Dinelli, B. M.; Dudhia, A.; Dufour, G.; Frith, S. M.; Froidevaux, L.; Godin-Beekmann, S.; Granville, J.; Harris, N. R. P.; Hoppel, K.; Hubert, D.; Kasai, Y.; Kurylo, M. J.; Kyrölä, E.; Lambert, J.-C.; Levelt, P. F.; McElroy, C. T.; McPeters, R. D.; Munro, R.; Nakajima, H.; Parrish, A.; Raspollini, P.; Remsberg, E. E.; Rosenlof, K. H.; Rozanov, A.; Sano, T.; Sasano, Y.; Shiotani, M.; Smit, H. G. J.; Stiller, G.; Tamminen, J.; Tarasick, D. W.; Urban, J.; van der A, R. J.; Veefkind, J. P.; Vigouroux, C.; von Clarmann, T.; von Savigny, C.; Walker, K. A.; Weber, M.; Wild, J.; Zawodny, J.

    2013-11-01

    Peak stratospheric chlorofluorocarbon (CFC) and other ozone depleting substance (ODS) concentrations were reached in the mid to late 1990s. Detection and attribution of the expected recovery of the stratospheric ozone layer in an atmosphere with reduced ODSs as well as efforts to understand the evolution of stratospheric ozone in the presence of increasing greenhouse gases are key current research topics. These require a critical examination of the ozone changes with an accurate knowledge of the spatial (geographical and vertical) and temporal ozone response. For such an examination, it is vital that the quality of the measurements used be as high as possible and measurement uncertainties well quantified. In preparation for the 2014 United Nations Environment Programme (UNEP)/World Meteorological Organization (WMO) Scientific Assessment of Ozone Depletion, the SPARC/IO3C/IGACO-O3/NDACC (SI2N) initiative was designed to study and document changes in the global ozone profile distribution. This requires assessing long-term ozone profile data sets in regards to measurement stability and uncertainty characteristics. The ultimate goal is to establish suitability for estimating long-term ozone trends to contribute to ozone recovery studies. Some of the data sets have been improved as part of this initiative with updated versions now available. This summary presents an overview of stratospheric ozone profile measurement data sets (ground- and satellite-based) available for ozone recovery studies. Here we document measurement techniques, spatial and temporal coverage, vertical resolution, native units and measurement uncertainties. In addition, the latest data versions are briefly described (including data version updates as well as detailing multiple retrievals when available for a given satellite instrument). Archive location information is for each data set is also given.

  10. Source attribution of tropospheric ozone

    NASA Astrophysics Data System (ADS)

    Butler, T. M.

    2015-12-01

    Tropospheric ozone is a harmful pollutant with adverse effects on human health and ecosystems. As well as these effects, tropospheric ozone is also a powerful greenhouse gas, with an anthropogenic radiative forcing one quarter of that of CO2. Along with methane and atmospheric aerosol, tropospheric ozone belongs to the so-called Short Lived Climate forcing Pollutants, or SLCP. Recent work has shown that efforts to reduce concentrations of SLCP in the atmosphere have the potential to slow the rate of near-term climate change, while simultaneously improving public health and reducing crop losses. Unlike many other SLCP, tropospehric ozone is not directly emitted, but is instead influenced by two distinct sources: transport of air from the ozone-rich stratosphere; and photochemical production in the troposphere from the emitted precursors NOx (oxides of nitrogen), CO (Carbon Monoxide), and VOC (volatile organic compounds, including methane). Better understanding of the relationship between ozone production and the emissions of its precursors is essential for the development of targeted emission reduction strategies. Several modeling methods have been employed to relate the production of tropospheric ozone to emissions of its precursors; emissions perturbation, tagging, and adjoint sensitivity methods all deliver complementary information about modelled ozone production. Most studies using tagging methods have focused on attribution of tropospheric ozone production to emissions of NOx, even though perturbation methods have suggested that tropospheric ozone is also sensitive to VOC, particularly methane. In this study we describe the implementation into a global chemistry-climate model of a scheme for tagging emissions of NOx and VOC with an arbitrary number of labels, which are followed through the chemical reactions of tropospheric ozone production in order to perform attribution of tropospehric ozone to its emitted precursors. Attribution is performed to both

  11. Stratospheric contribution to surface ozone in the desert Southwest during the 2013 Las Vegas Ozone Study

    NASA Astrophysics Data System (ADS)

    Langford, A. O.; Senff, C. J.; Alvarez, R. J. _II, II; Brioude, J. F.; Cooper, O. R.; Holloway, J. S.; Lin, M.; Marchbanks, R.; Pierce, R. B.; Reddy, P. J.; Sandberg, S.; Weickmann, A. M.; Williams, E. J.; Gustin, M. S.; Iraci, L. T.; Leblanc, T.; Yates, E. L.

    2014-12-01

    The 2013 Las Vegas Ozone Study (LVOS) was designed to investigate the potential impact of stratosphere-troposphere transport (STT) and long-range transport of pollution from Asia on surface O3 concentrations in Clark County, NV. This measurement campaign, which took place in May and June of 2013, was conducted at Angel Peak, NV, a high elevation site about 2.8 km above mean sea level and 45 km west of Las Vegas. The study was organized around the NOAA ESRL truck-based TOPAZ scanning ozone lidar with collocated in situ sampling of O3, CO, and meteorological parameters. These measurements were supported by the NOAA/NESDIS real time modelling system (RAQMS), FLEXPART particle dispersion model, and the NOAA GFDL AM3 model. In this talk, I will describe one of several STT events that occurred during the LVOS campaign. This intrusion, which was profiled by TOPAZ on the night of May 24-25, was also sampled by the NASA Alpha Jet, the Table Mountain ozone lidar, and by an ozonesonde flying above southern California. This event also led to significant ozone increases at surface monitors operated by Clark County, the California Air Resources Board, the U.S. National Park Service, and the Nevada Rural Ozone Initiative (NRVOI), and resulted in exceedances of the 2008 75 ppbv O3 NAAQS both in Clark County and in surrounding areas of Nevada and southern California. The potential implications of this and similar events for air quality compliance in the western U.S. will be discussed.

  12. Ozone adsorption on carbon nanoparticles

    NASA Astrophysics Data System (ADS)

    Chassard, Guillaume; Gosselin, Sylvie; Visez, Nicolas; Petitprez, Denis

    2014-05-01

    Carbonaceous particles produced by incomplete combustion or thermal decomposition of hydrocarbons are ubiquitous in the atmosphere. On these particles are adsorbed hundreds of chemical species. Those of great concern to health are polycyclic aromatic hydrocarbons (PAHs). During atmospheric transport, particulate PAHs react with gaseous oxidants. The induced chemical transformations may change toxicity and hygroscopicity of these potentially inhalable particles. The interaction between ozone and carbon particles has been extensively investigated in literature. However ozone adsorption and surface reaction mechanisms are still ambiguous. Some studies described a fast catalytic decomposition of ozone initiated by an atomic oxygen chemisorption followed by a molecular oxygen release [1-3]. Others suggested a reversible ozone adsorption according to Langmuir-type behaviour [4,5]. The aim of this present study is a better understanding of ozone interaction with carbon surfaces. An aerosol of carbon nanoparticles was generated by flowing synthetic air in a glass tube containing pure carbon (primary particles < 50 nm), under magnetic stirring. The aerosol was then mixed with ozone in an aerosol flow tube. Ozone uptake experiments were performed with different particles concentrations with a fixed ozone concentration. The influence of several factors on kinetics was examined: initial ozone concentration, particle size (50 nm ≤ Dp ≤ 200 nm) and competitive adsorption (with probe molecule and water). The effect of initial ozone concentration was first studied. Accordingly to literature, it has been observed that the number of gas-phase ozone molecules lost per unit particle surface area tends towards a plateau for high ozone concentration suggesting a reversible ozone adsorption according to a Langmuir mechanism. We calculated the initial reaction probability between O3 and carbon particles.An initial uptake coefficient of 1.10-4 was obtained. Similar experiments were

  13. Evaluation of modeled surface ozone biases as a function of cloud cover fraction

    NASA Astrophysics Data System (ADS)

    Kim, H. C.; Lee, P.; Ngan, F.; Tang, Y.; Yoo, H. L.; Pan, L.

    2015-09-01

    A regional air-quality forecast system's model of surface ozone variability based on cloud coverage is evaluated using satellite-observed cloud fraction (CF) information and a surface air-quality monitoring system. We compared CF and daily maximum ozone from the National Oceanic and Atmospheric Administration's National Air Quality Forecast Capability (NOAA NAQFC) with CFs from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the US Environmental Protection Agency's AirNow surface ozone measurements during May to October 2014. We found that observed surface ozone shows a negative correlation with the MODIS CFs, showing around 1 ppb decrease for 10 % MODIS CF change over the contiguous United States, while the correlation of modeled surface ozone with the model CFs is much weaker, showing only -0.5 ppb per 10 % NAQFC CF change. Further, daytime CF differences between MODIS and NAQFC are correlated with modeled surface-ozone biases between AirNow and NAQFC, showing -1.05 ppb per 10 % CF change, implying that spatial and temporal misplacement of the modeled cloud field might have biased modeled surface ozone level. Current NAQFC cloud fields seem to have fewer CFs compared to MODIS cloud fields (mean NAQFC CF = 0.38 and mean MODIS CF = 0.55), contributing up to 35 % of surface-ozone bias in the current NAQFC system.

  14. Options to accelerate ozone recovery: ozone and climate benefits

    NASA Astrophysics Data System (ADS)

    Daniel, J. S.; Fleming, E. L.; Portmann, R. W.; Velders, G. J. M.; Jackman, C. H.; Ravishankara, A. R.

    2010-08-01

    Hypothetical reductions in future emissions of ozone-depleting substances (ODSs) and N2O are evaluated in terms of effects on equivalent effective stratospheric chlorine (EESC), globally-averaged total column ozone, and radiative forcing through 2100. Due to the established success of the Montreal Protocol, these actions can have only a fraction of the impact on ozone depletion that regulations already in force have had. If all anthropogenic ODS and N2O emissions were halted beginning in 2011, ozone is calculated to be higher by about 1-2% during the period 2030-2100 compared to a case of no additional restrictions. Direct radiative forcing by 2100 would be about 0.23 W/m2 lower from the elimination of anthropogenic N2O emissions and about 0.005 W/m2 lower from the destruction of the chlorofluorocarbon (CFC) bank. Due to the potential impact of N2O on future ozone levels, we provide an approach to incorporate it into the EESC formulation, which is used extensively in ozone depletion analyses. The ability of EESC to describe total ozone changes arising from additional ODS and N2O controls is also quantified.

  15. Nitroaromatic hydrocarbon ozonation in water. 1: Single ozonation

    SciTech Connect

    Beltran, F.J.; Encinar, J.M.; Alonso, M.A.

    1998-01-01

    Single ozonation of two nitroaromatic hydrocarbons (nitrobenzene and 2,6-dinitrotoluene) under different experimental conditions (ozone feed rate, pH, temperature, hydroxyl radical scavengers) has been studied. The absence of hydroxyl radical scavengers, pHs 7--9, and temperatures below 30 C are optimum conditions for nitroaromatic removal. Due to the importance of hydroxyl radical reactions, removal rates in natural water are much lower than those observed in laboratory ultrapure water. Rate constants of the direct reaction between ozone and nitroaromatic hydrocarbons at 20 C have been found to be lower than 6 M{sup {minus}1} s{sup {minus}1}. More than 99% of nitroaromatic removal is due to hydroxyl radical oxidation. Single ozonation of nitroaromatics can then be classified as a real advanced oxidation technology. Nitrophenols, compounds very reactive toward ozone and hydroxyl radicals, and 2,6-dinitrobenzaldehyde, identified in the single ozonation of nitrobenzene and 2,6-dinitrotoluene, respectively, are some of the first intermediates of single ozonation.

  16. Interannual Variability in Baseline Ozone and Its Relationship to Surface Ozone in the Western U.S.

    PubMed

    Baylon, Pao M; Jaffe, Daniel A; Pierce, R Bradley; Gustin, Mae S

    2016-03-15

    Baseline ozone refers to observed concentrations of tropospheric ozone at sites that have a negligible influence from local emissions. The Mount Bachelor Observatory (MBO) was established in 2004 to examine baseline air masses as they arrive to North America from the west. In May 2012, we observed an O3 increase of 2.0-8.5 ppbv in monthly average maximum daily 8-hour average O3 mixing ratio (MDA8 O3) at MBO and numerous other sites in the western U.S. compared to previous years. This shift in the O3 distribution had an impact on the number of exceedance days. We also observed a good correlation between daily MDA8 variations at MBO and at downwind sites. This suggests that under specific meteorological conditions, synoptic variation in O3 at MBO can be observed at other surface sites in the western U.S. At MBO, the elevated O3 concentrations in May 2012 are associated with low CO values and low water vapor values, consistent with transport from the upper troposphere/lower stratosphere (UT/LS). Furthermore, the Real-time Air Quality Modeling System (RAQMS) analyses indicate that a large flux of O3 from the UT/LS in May 2012 contributed to the observed enhanced O3 across the western U.S. Our results suggest that a network of mountaintop observations, LiDAR and satellite observations of O3 could provide key data on daily and interannual variations in baseline O3. PMID:26882468

  17. Total ozone changes in the 1987 Antarctic ozone hole

    NASA Technical Reports Server (NTRS)

    Krueger, Arlin J.; Schoeberl, Mark R.; Doiron, Scott D.; Sechrist, Frank; Galimore, Reginald

    1988-01-01

    The development of the Antarctic ozone minimum was observed in 1987 with the Nimbus 7 Total Ozone Mapping Spectrometer (TOMS) instrument. In the first half of August the near-polar (60 and 70 deg S) ozone levels were similar to those of recent years. By September, however, the ozone at 70 and 80 deg S was clearly lower than any previous year including 1985, the prior record low year. The levels continued to decrease throughout September until October 5 when a new record low of 109 DU was established at a point near the South Pole. This value is 29 DU less than the lowest observed in 1985 and 48 DU less than the 1986 low. The zonal mean total ozone at 60 deg S remained constant throughout the time of ozone hole formation. The ozone decline was punctuated by local minima formed away from the polar night boundary at about 75 deg S. The first of these, on August 15 to 17, formed just east of the Palmer Peninsula and appears to be a mountain wave. The second major minimum formed on September 5 to 7 again downwind of the Palmer Peninsula. This event was larger in scale than the August minimum and initiated the decline of ozone across the polar region. The 1987 ozone hole was nearly circular and pole centered for its entire life. In previous years the hole was perturbed by intrusions of the circumpolar maximum into the polar regions, thus causing the hole to be elliptical. The 1987 hole also remained in place until the end of November, a few days longer than in 1985, and this persistence resulted in the latest time for recovery to normal values yet observed.

  18. Is the Ozone Hole over Your Classroom?

    ERIC Educational Resources Information Center

    Cordero, Eugene C.

    2002-01-01

    Reports on a survey of first year university science students regarding their understanding of the ozone layer, ozone depletion, and the effect of ozone depletion on Australia. Suggests that better teaching resources for environmental issues such as ozone depletion and global warming are needed before improvements in student understanding can be…

  19. Atmospheric ozone and man-made pollution.

    PubMed

    Fabian, P

    1976-06-01

    Atmospheric photochemistry and transport processes, related to the ozone layer, are discussed. Natural or man-made changes of the biosphere, variations of radiation, or general circulation as well as anthropogenic release of ozone-destroying catalysts are likely to alter the earth's ozone shield. The possible effects of ozone depletion caused by supersonic aircraft, nuclear weapons, nitrogen fertilizers, and chlorofluoromethanes are discussed.

  20. Air Quality Modeling of Ozone Radical Precursors in Houston

    NASA Astrophysics Data System (ADS)

    Rappenglueck, B.; Czader, B.; Li, X.

    2013-05-01

    The Houston-Galveston area has one of the highest ozone concentrations in the U.S., often exceeding the U.S. National Ambient Air Quality Standard for ozone. Photochemical modeling of ozone formation in the Houston area generally underestimates the concentrations of free radical precursors contributing to ozone formation. Here we present modeling results using the Weather Research Forecast - Community Multiscale Air Quality (WRF-CMAQ) modeling system for the Houston-Galveston area. Meteorological parameters predicted by WRF are well simulated most of the time, including planetary boundary layer heights. Air quality simulations for the Houston-Galveston-Brazoria area using the combined WRF-SMOKE-CMAQ system showed overall good results for ozone and many other trace gases. HONO morning peaks are no longer underpredicted, on some occasions they are slightly overpredicted, which can be linked to NO2 overprediction. However, CMAQ mispredicts other trace gases like HO2, H2O2 and CH3OOH concentrations. The WRF-SMOKE-CMAQ system was also used to elucidate the relative importance of various photolysis processes as radical sources in the Houston atmosphere. Morning HOx formation is dominated by HONO while ozone contributes the most during midday. HONO contribution to HOx formation is more pronounced at the surface layer where most of it is formed. On the other hand, radical production from ozone is more important at elevated levels where higher concentrations of ozone are observed. Formaldehyde contributes up to 40% and also peaks during mid-day, but on days when high morning concentrations of formaldehyde are observed its contribution to HOx in the morning exceeds that of ozone. Photolysis of H2O2 is a minor contributor to radical levels. The process analysis tool available in CMAQ was utilized to analyze photochemical processes leading to ozone production and chemical transformations along trajectories linking a site at the Houston Ship Channel and the University of

  1. Corona discharge influences ozone concentrations near rats.

    PubMed

    Goheen, Steven C; Gaither, Kari; Anantatmula, Shantha M; Mong, Gary M; Sasser, Lyle B; Lessor, Delbert

    2004-02-01

    Ozone can be produced by corona discharge either in dry air or when one electrode is submerged in water. Since ozone is toxic, we examined whether ozone production by corona near laboratory animals could reach levels of concern. Male rats were exposed to a corona discharge and the concentration of ozone produced was measured. The resulting concentration of ozone ranged from ambient levels to 250 ppb when animals were located 1 cm from a 10 kV source. Similar ozone concentrations were observed when a grounded water source was present. Possible explanations for, as well as concerns regarding, ozone production under these conditions are discussed. PMID:14735560

  2. Regulatory ozone modeling: status, directions, and research needs.

    PubMed Central

    Georgopoulos, P G

    1995-01-01

    The Clean Air Act Amendments (CAAA) of 1990 have established selected comprehensive, three-dimensional, Photochemical Air Quality Simulation Models (PAQSMs) as the required regulatory tools for analyzing the urban and regional problem of high ambient ozone levels across the United States. These models are currently applied to study and establish strategies for meeting the National Ambient Air Quality Standard (NAAQS) for ozone in nonattainment areas; State Implementation Plans (SIPs) resulting from these efforts must be submitted to the U.S. Environmental Protection Agency (U.S. EPA) in November 1994. The following presentation provides an overview and discussion of the regulatory ozone modeling process and its implications. First, the PAQSM-based ozone attainment demonstration process is summarized in the framework of the 1994 SIPs. Then, following a brief overview of the representation of physical and chemical processes in PAQSMs, the essential attributes of standard modeling systems currently in regulatory use are presented in a nonmathematical, self-contained format, intended to provide a basic understanding of both model capabilities and limitations. The types of air quality, emission, and meteorological data needed for applying and evaluating PAQSMs are discussed, as well as the sources, availability, and limitations of existing databases. The issue of evaluating a model's performance in order to accept it as a tool for policy making is discussed, and various methodologies for implementing this objective are summarized. Selected interim results from diagnostic analyses, which are performed as a component of the regulatory ozone modeling process for the Philadelphia-New Jersey region, are also presented to provide some specific examples related to the general issues discussed in this work. Finally, research needs related to a) the evaluation and refinement of regulatory ozone modeling, b) the characterization of uncertainty in photochemical modeling, and c

  3. Unprecedented Arctic ozone loss in 2011.

    PubMed

    Manney, Gloria L; Santee, Michelle L; Rex, Markus; Livesey, Nathaniel J; Pitts, Michael C; Veefkind, Pepijn; Nash, Eric R; Wohltmann, Ingo; Lehmann, Ralph; Froidevaux, Lucien; Poole, Lamont R; Schoeberl, Mark R; Haffner, David P; Davies, Jonathan; Dorokhov, Valery; Gernandt, Hartwig; Johnson, Bryan; Kivi, Rigel; Kyrö, Esko; Larsen, Niels; Levelt, Pieternel F; Makshtas, Alexander; McElroy, C Thomas; Nakajima, Hideaki; Parrondo, Maria Concepción; Tarasick, David W; von der Gathen, Peter; Walker, Kaley A; Zinoviev, Nikita S

    2011-10-27

    Chemical ozone destruction occurs over both polar regions in local winter-spring. In the Antarctic, essentially complete removal of lower-stratospheric ozone currently results in an ozone hole every year, whereas in the Arctic, ozone loss is highly variable and has until now been much more limited. Here we demonstrate that chemical ozone destruction over the Arctic in early 2011 was--for the first time in the observational record--comparable to that in the Antarctic ozone hole. Unusually long-lasting cold conditions in the Arctic lower stratosphere led to persistent enhancement in ozone-destroying forms of chlorine and to unprecedented ozone loss, which exceeded 80 per cent over 18-20 kilometres altitude. Our results show that Arctic ozone holes are possible even with temperatures much milder than those in the Antarctic. We cannot at present predict when such severe Arctic ozone depletion may be matched or exceeded. PMID:21964337

  4. Thomas calls stratospheric ozone depletion rate alarming; urges CFC, halon phaseout

    SciTech Connect

    Not Available

    1988-11-01

    US Environmental Protection Agency Administrator Lee M. Thomas on September 28 called for even greater efforts in halting the depletion of stratospheric ozone by asking all nations to ratify the Montreal Protocol and then move toward a complete phaseout of ozone-depleting chlorofluorocarbons (CFCs) and halons. We must go further than a 50-percent reduction in these chemicals in order to stabilize ozone levels. The Protocol has been signed by 45 nations, but still needs ratification by the European nations and the European Economic Community in order to enter into force next January. It is increasingly clear that we as a global environmental community must use the Protocol to go even further to eliminate these chemicals which damage the stratospheric-ozone layer and threaten our future.

  5. Brewer Umkehr ozone profile retrievals

    NASA Astrophysics Data System (ADS)

    Petropavlovskikh, I. V.; Disterhoft, P.; Lantz, K. O.; Bhartia, P. K.; McPeters, R. D.; Flynn, L. E.; Oltmans, S. J.; Johnson, B. J.; Stanek, M.

    2011-12-01

    The Dobson Umkehr network has been a key data set for stratospheric ozone trend calculations (WMO Ozone assessments) and has earned its place as a benchmark network for stratospheric ozone profile observations. The Umkehr data has also been used to provide a long-term reference to the merging of the satellite ozone records (MOD), estimate the seasonal influence of an 11-year solar signal in the vertical distribution of stratospheric ozone, and to assess the ability of several remote and in-situ sensing systems in capturing ozone variability. It was found that Dobson Umkehr measurement errors were often comparable to errors derived for satellite and ozone-sounding methods. The Umkehr measurements are also available from the Brewer spectrophotometers [McElroy et al., 1995]. In 2005, the Dobson Umkehr algorithm (UMK04) was modified to retrieve ozone profile data from Brewer Umkehr measurements taken at two spectral channels [Petropavlovskikh et al, 2011]. The PC version of the Brewer algorithm was developed by M. Stanek (IOC, Canada and Czech Republic Meteorological Institute) in close collaboration with I. Petropavlovskikh. It was implemented at the NEUBrew network for operational processing of Umkehr data retrieved daily for all operational sites. The most recently developed Brewer ozone retrieval algorithm (MSBU) utilizes measurements that are currently available from the operational Brewer instruments. Umkehr measurements at multiple wavelength channels (similar to the satellite BUV method) and significantly reduced range of solar zenith angle are used for the twice a day operational ozone profile retrievals. Intercomparisons against ozone climatology, sounding, satellite overpasses and Dobson ozone datasets for NOASA/Goddard, Boulder, CO and MLO, HI sites are presented in this paper. The MSBU algorithm reduces noise in the intra-annual variability of the Brewer retrieved ozone as compared to the single pair ozone retrieval. Tropospheric ozone retrievals also

  6. Effects of stratospheric ozone recovery on photochemistry and ozone air quality in the troposphere

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Wu, S.; Huang, Y.; Wang, Y.

    2014-04-01

    There has been significant stratospheric ozone depletion since the late 1970s due to ozone-depleting substances (ODSs). With the implementation of the Montreal Protocol and its amendments and adjustments, stratospheric ozone is expected to recover towards its pre-1980 level in the coming decades. In this study, we examine the implications of stratospheric ozone recovery for the tropospheric chemistry and ozone air quality with a global chemical transport model (GEOS-Chem). With a full recovery of the stratospheric ozone, the projected increases in ozone column range from 1% over the low latitudes to more than 10% over the polar regions. The sensitivity factor of troposphere ozone photolysis rate, defined as the percentage changes in surface ozone photolysis rate for 1% increase in stratospheric ozone column, shows significant seasonal variation but is always negative with absolute value larger than one. The expected stratospheric ozone recovery is found to affect the tropospheric ozone destruction rates much more than the ozone production rates. Significant decreases in surface ozone photolysis rates due to stratospheric ozone recovery are simulated. The global average tropospheric OH decreases by 1.7%, and the global average lifetime of tropospheric ozone increases by 1.5%. The perturbations to tropospheric ozone and surface ozone show large seasonal and spatial variations. General increases in surface ozone are calculated for each season, with increases by up to 0.8 ppbv in the remote areas. Increases in ozone lifetime by up to 13% are found in the troposphere. The increased lifetimes of tropospheric ozone in response to stratospheric ozone recovery enhance the intercontinental transport of ozone and global pollution, in particular for the summertime. The global background ozone attributable to Asian emissions is calculated to increase by up to 15% or 0.3 ppbv in the Northern Hemisphere in response to the projected stratospheric ozone recovery.

  7. Trends in ozone profile measurements

    NASA Technical Reports Server (NTRS)

    Johnston, H.; Aikin, A.; Barnes, R.; Chandra, S.; Cunnold, D.; Deluisi, J.; Gille, J. C.; Hudson, R.; Mccormick, M. P.; Mcmaster, L.

    1989-01-01

    From an examination of the agreements and differences between different satellite instruments, it is difficult to believe that existing satellite instruments determine upper stratospheric ozone much better than 4 pct.; by extension, it probably would require at least a 4 pct. change to be reliably detected as a change. The best estimates of the vertical profiles of ozone change in the upper stratosphere between 1979 and 1986 are judged to be those given by the two SAGE satellite instruments. SAGE-2 minus SAGE-1 gives a much lower ozone reduction than that given by the archived Solar Backscatter UV data. The average SAGE profiles of ozone changes between 20 and 50 degs north and between 20 and 50 degs south are given. The SAGE-1 and SAGE-2 comparison gives an ozone reduction of about 4 pct. at 25 km over temperate latitudes. Five ground based Umkehr stations between 36 and 52 degs north, corrected for the effects of volcanic aerosols, report an ozone reduction between 1979 and 1987 at Umkehr layer 8 of 9 + or - 5 pct. The central estimate of upper stratospheric ozone reduction given by SAGE at 40 km is less than the central value estimated by the Umkehr method at layer 8.

  8. The role of bay breezes and regional transport on a high surface ozone episode during the Houston, Texas DISCOVER-AQ field campaign

    NASA Astrophysics Data System (ADS)

    Loughner, C.; Follette-Cook, M. B.; Pickering, K. E.; Estes, M. J.

    2014-12-01

    The highest observed surface ozone concentrations in the Houston metropolitan area in 2013 occurred on September 25, which coincided with the Texas DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign. Surface ozone was elevated throughout the Houston metropolitan area. Maximum 8-hour average ozone peaked along the western shore of Galveston Bay, reaching 124 ppbv, almost 50 ppbv above the current EPA standard of 75 ppbv, at La Porte Sylvan Beach. Continental air pollution from the north and northeast was transported into the Houston metropolitan area where it mixed with locally generated emissions. A bay breeze circulation formed causing pollutants that were transported out over the water in the morning to recirculate back inland where they mixed with freshly emitted pollution near the bay breeze convergence zone. The highest surface ozone concentrations were reported near the bay breeze front at La Porte Sylvan Beach. This ozone episode will be presented using measurements made during the DISCOVER-AQ field campaign and WRF and CMAQ model simulations.

  9. Correlative studies of satellite ozone sensor measurements

    NASA Technical Reports Server (NTRS)

    Lovill, J. E.; Ellis, J. S.

    1983-01-01

    Comparisons are made between total ozone measurements made by four satellite ozone sensors (TOMS, SBUV, TOVS and MFR). The comparisons were made during July 1979 when all sensors were operating simultaneously. The TOMS and SBUV sensors were observed to measure less total ozone than the MFR sensor, 10 and 15 Dobson units (DU) respectively. The MFR and TOMS sensors measured less ozone than the TOVS sensor, 19 and 28 DU, respectively. Latitudinal variability of the total ozone comparisons is discussed.

  10. The effect of ozone depletion on the Southern Annular Mode and stratosphere-troposphere coupling

    NASA Astrophysics Data System (ADS)

    Dennison, Fraser W.; McDonald, Adrian J.; Morgenstern, Olaf

    2015-07-01

    The aim of this study is to investigate the influence of ozone depletion and recovery on the Southern Annular Mode (SAM) and stratosphere-troposphere coupling. Using the National Institute of Water and Atmospheric Research-United Kingdom Chemistry and Aerosols chemistry-climate model, we compare reference runs that include forcing due to greenhouse gases and ozone-depleting substances to sensitivity simulations in which ozone-depleting substances are fixed at their 1960 levels. We find that ozone depletion leads to an increased frequency of extreme anomalies and increased persistence of the SAM in the stratosphere as well as stronger, more persistent stratosphere-troposphere coupling. Currently, the stratosphere provides an appreciable amount of predictability to the troposphere on timescales of 1 or 2 months; however, we find that this effect reduces over time as stratospheric ozone recovers to preozone hole levels toward the latter part of this century.

  11. ADVANCED OXIDATION: OXALATE DECOMPOSITION TESTING WITH OZONE

    SciTech Connect

    Ketusky, E.; Subramanian, K.

    2012-02-29

    dissolution equilibrium, and then decomposed to {le} 100 Parts per Million (ppm) oxalate. Since AOP technology largely originated on using ultraviolet (UV) light as a primary catalyst, decomposition of the spent oxalic acid, well exposed to a medium pressure mercury vapor light was considered the benchmark. However, with multi-valent metals already contained in the feed, and maintenance of the UV light a concern; testing was conducted to evaluate the impact from removing the UV light. Using current AOP terminology, the test without the UV light would likely be considered an ozone based, dark, ferrioxalate type, decomposition process. Specifically, as part of the testing, the impacts from the following were investigated: (1) Importance of the UV light on the decomposition rates when decomposing 1 wt% spent oxalic acid; (2) Impact of increasing the oxalic acid strength from 1 to 2.5 wt% on the decomposition rates; and (3) For F-area testing, the advantage of increasing the spent oxalic acid flowrate from 40 L/min (liters/minute) to 50 L/min during decomposition of the 2.5 wt% spent oxalic acid. The results showed that removal of the UV light (from 1 wt% testing) slowed the decomposition rates in both the F & H testing. Specifically, for F-Area Strike 1, the time increased from about 6 hours to 8 hours. In H-Area, the impact was not as significant, with the time required for Strike 1 to be decomposed to less than 100 ppm increasing slightly, from 5.4 to 6.4 hours. For the spent 2.5 wt% oxalic acid decomposition tests (all) without the UV light, the F-area decompositions required approx. 10 to 13 hours, while the corresponding required H-Area decompositions times ranged from 10 to 21 hours. For the 2.5 wt% F-Area sludge, the increased availability of iron likely caused the increased decomposition rates compared to the 1 wt% oxalic acid based tests. In addition, for the F-testing, increasing the recirculation flow rates from 40 liter/minute to 50 liter/minute resulted in an

  12. Factors influencing the ground level distribution of ozone in Europe.

    PubMed

    Derwent, R G; Kay, P J

    1988-01-01

    Ozone is a widely distributed pollutant in the atmospheric boundary layer over north west Europe. Three main sources have been identified: the stratosphere, the free troposphere and boundary layer photochemical production. The pattern of ground level ozone concentrations resulting from these three sources cannot be accurately specified. Ozone shows significant variations in space and time but because of the high cost of continuous monitoring equipment, spatial variations on a national and international basis have not been studied in detail. Variations in ozone concentrations at individual monitoring sites have been given a great deal of attention and experience gained from United Kingdom monitoring sites is described in some detail. The averaging time statistical model of Larsen is employed to relate the exposure levels measured over different averaging periods. Diurnal variations have a major influence on exposure levels at sites nominally exposed to the same regional ozone distribution. The physical and chemical mechanisms which give rise to diurnal variations are detailed so that sites can be screened for different diurnal behaviour characteristics.

  13. Causes and effects of a hole. [in Antarctic ozone layer

    NASA Technical Reports Server (NTRS)

    Margitan, J. J.

    1987-01-01

    Preliminary results from the U.S. National Ozone Expedition (NOZE) to Antarctica are reviewed. The NOZE ozonesonde measurements showed significant vertical structure in the hole, with 80 percent depletion in some of the 1 km layers but only 20 percent in adjacent layers. The depletion was confined to the 12-20 km region, beginning first at higher altitude and progressing downward. This is strong evidence against the theory that the ozone hole is due to solar activity producing odd nitrogen at high altitudes which is transported downwards, leading to enhanced odd-nitrogen catalytic cycles that destroy ozone. Nitrous oxide data show unusually low concentrations within the polar vortex, which is evidence against the theory that the hole is caused by a purely dynamical mechanism in which rising air motions within the polar vortex lead to reduced column densities of ozone. It is tentatively concluded that a chemical mechanism involving man-made chlorofluorocarbons is the likely cause of ozone depletion in the hole.

  14. Common Calibration Source for Monitoring Long-term Ozone Trends

    NASA Technical Reports Server (NTRS)

    Kowalewski, Matthew

    2004-01-01

    Accurate long-term satellite measurements are crucial for monitoring the recovery of the ozone layer. The slow pace of the recovery and limited lifetimes of satellite monitoring instruments demands that datasets from multiple observation systems be combined to provide the long-term accuracy needed. A fundamental component of accurately monitoring long-term trends is the calibration of these various instruments. NASA s Radiometric Calibration and Development Facility at the Goddard Space Flight Center has provided resources to minimize calibration biases between multiple instruments through the use of a common calibration source and standardized procedures traceable to national standards. The Facility s 50 cm barium sulfate integrating sphere has been used as a common calibration source for both US and international satellite instruments, including the Total Ozone Mapping Spectrometer (TOMS), Solar Backscatter Ultraviolet 2 (SBUV/2) instruments, Shuttle SBUV (SSBUV), Ozone Mapping Instrument (OMI), Global Ozone Monitoring Experiment (GOME) (ESA), Scanning Imaging SpectroMeter for Atmospheric ChartographY (SCIAMACHY) (ESA), and others. We will discuss the advantages of using a common calibration source and its effects on long-term ozone data sets. In addition, sphere calibration results from various instruments will be presented to demonstrate the accuracy of the long-term characterization of the source itself.

  15. The Antarctic ozone lidar system

    NASA Astrophysics Data System (ADS)

    Stefanutti, L.; Castagnoli, F.; del Guasta, M.; Morandi, M.; Sacco, V. M.; Zuccagnoli, L.; Godin, S.; Megie, G.; Porteneuve, J.

    1992-07-01

    A new complex lidar system, designated POLE, for measuring tropospheric and stratospheric ozone, stratospheric aerosols, and polar stratospheric and tropospheric clouds is described. The lidar system is comprised of a Rayleigh lidar, an upper stratospheric ozone lidar, a low-altitude or tropospheric ozone lidar, and an aerosol backscattering depolarization lidar. The paper describes the characteristics of these lidars and the measurements obtained by each of them, together with the features of various subsystems of POLE, and presents results of measurements performed during the 1991 antarctic winter.

  16. Ozone and Ozonated Oils in Skin Diseases: A Review

    PubMed Central

    Travagli, V.; Zanardi, I.; Valacchi, G.; Bocci, V.

    2010-01-01

    Although orthodox medicine has provided a variety of topical anti-infective agents, some of them have become scarcely effective owing to antibiotic- and chemotherapeutic-resistant pathogens. For more than a century, ozone has been known to be an excellent disinfectant that nevertheless had to be used with caution for its oxidizing properties. Only during the last decade it has been learned how to tame its great reactivity by precisely dosing its concentration and permanently incorporating the gas into triglycerides where gaseous ozone chemically reacts with unsaturated substrates leading to therapeutically active ozonated derivatives. Today the stability and efficacy of the ozonated oils have been already demonstrated, but owing to a plethora of commercial products, the present paper aims to analyze these derivatives suggesting the strategy to obtain products with the best characteristics. PMID:20671923

  17. Dobson spectrophotometer ozone measurements during international ozone rocketsonde intercomparison

    NASA Technical Reports Server (NTRS)

    Parsons, C. L.

    1980-01-01

    Measurements of the total ozone content of the atmosphere, made with seven ground based instruments at a site near Wallops Island, Virginia, are discussed in terms for serving as control values with which the rocketborne sensor data products can be compared. These products are profiles of O3 concentration with altitude. By integrating over the range of altitudes from the surface to the rocket apogee and by appropriately estimating the residual ozone amount from apogee to the top of the atmosphere, a total ozone amount can be computed from the profiles that can be directly compared with the ground based instrumentation results. Dobson spectrophotometers were used for two of the ground-based instruments. Preliminary data collected during the IORI from Dobson spectrophotometers 72 and 38 are presented. The agreement between the two and the variability of total ozone overburden through the experiment period are discussed.

  18. Sensitivity Studies for Assimilated Ozone Profiles

    NASA Technical Reports Server (NTRS)

    Stajner, Ivanka; Winslow, Nathan; Wargan, Krzysztof; Rood, Richard; Pawson, Steven

    2002-01-01

    An ozone data assimilation system at the NASA/Goddard Data Assimilation Office (DAO) produces three-dimensional global ozone fields. They are obtained by assimilating ozone retrieved from the Solar Backscatter UltraViolet/2 (SBUV/2) instrument and the Earth Probe Total Ozone Mapping Spectrometer (EP TOMS) measurements into an off-line parameterized chemistry and transport model. In this talk we focus on the quality of lower stratospheric assimilated ozone profiles. Ozone in the lower stratosphere plays a key role in the forcing of climate. A biased ozone field in this region will adversely impact calculations of the stratosphere-troposphere exchange and, when used as a first guess in retrievals, the values determined from satellite observations. The SBUV/2 ozone data have a coarse vertical resolution with increased uncertainty below the ozone maximum, and TOMS provides only total ozone columns. Thus, the assimilated ozone profiles in the lower stratosphere are only weakly constrained by the incoming SBUV and TOMS data. Consequently, the assimilated ozone distribution should be sensitive to changes in inputs to the statistical analysis scheme. We investigate the sensitivity of assimilated ozone profiles to changes in a variety of system inputs: TOMS and SBUV/2 data selection, forecast and observations error covariance models, inclusion or omission of a parameterized chemistry model, and different versions of DAO assimilated wind fields used to drive the transport model. Comparisons of assimilated ozone fields with independent observations, primarily ozone sondes, are used to determine the impact of each of these changes.

  19. Modeling Stomatal Conductance to Estimate Seasonal Uptake in the Ozone-Sensitive Bioindicator Plant Common Milkweed (A. syriaca L.)

    NASA Astrophysics Data System (ADS)

    Bergweiler, C.

    2008-12-01

    The US EPA National Ambient Air Quality Standard (NAAQS) was not conceived to nor does it provide an accurate definition of the absorbed ozone dose or baseline exposure level to protect vegetation. This research presents a multiplicative modeling approach based not only on atmospheric, but on equally important physiological, phenological, and environmental parameters. Physiological constraints on ozone uptake demonstrate that actual absorption is substantially lower than that assumed by a simple interpretation of hourly atmospheric ozone concentrations. Coupled with development of foliar injury expression this provides evidence that tropospheric ozone is more toxic to vegetation than is currently understood.

  20. Identifying and forecasting deep stratospheric ozone intrusions over the western United States from space

    NASA Astrophysics Data System (ADS)

    Lin, M.; Fiore, A. M.; Horowitz, L. W.; Cooper, O. R.; Langford, A. O.; Pan, L.; Liu, X.; Reddy, P. J.

    2012-12-01

    Recent studies have shown that deep stratospheric ozone intrusions can episodically enhance ground-level ozone above the health-based standard over the western U.S. in spring. Advanced warning of incoming intrusions could be used by state agencies to inform the public about poor air quality days. Here we explore the potential for using total ozone retrievals (version 5.2, level 3) at twice daily near global coverage from the AIRS instrument aboard the NASA Aqua satellite to identify stratospheric intrusions and forecast the eventual surface destination of transported stratospheric ozone. The method involves the correlation of AIRS daily total ozone columns at each 1ox1o grid box ~1-3 days prior to stratospheric enhancements to daily maximum 8-hour average ozone at a selected surface site using datasets from April to June in 2003-2011. The surface stratospheric enhancements are estimated by the GFDL AM3 chemistry-climate model which includes full stratospheric and tropospheric chemistry and is nudged to reanalysis winds. Our earlier work shows that the model presents deep stratospheric intrusions over the Western U.S. consistently with observations from AIRS, surface networks, daily ozone sondes, and aircraft lidar available in spring of 2010 during the NOAA CalNex field campaign. For the 15 surface sites in the U.S. Mountain West considered, a correlation coefficient of 0.4-0.7 emerges with AIRS ozone columns over 30o-50oN latitudes and 125o-105oW longitudes - variability in the AIRS column within this spatial domain indicates incoming intrusions. For each "surface receptor site", the spatial domain can narrow to an area ~5ox5o northwest of the individual site, with the strong correlation (0.5-0.7) occurring when the AIRS data is lagged by 1 day from the AM3 stratospheric enhancements in surface air. The spatial pattern of correlations is consistent with our process-oriented understanding developed from case studies of extreme intrusions. Surface observations