Science.gov

Sample records for 8-hour ozone standards

  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, 2014 CFR

    2014-07-01

    ... 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

    ... 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...

  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

    ... 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...

  5. 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...

  6. 77 FR 43521 - Final Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-25

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 81 RIN 2060-AO96 Final Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: Classification of Areas That Were Initially Classified Under Subpart 1; Revision of the Anti-Backsliding Provisions To Address...

  7. 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

    ... Revision; State of New Jersey'' proposed April 23, 2010 (75 FR 21197) and final rulemaking August 3, 2010... Control Measure'' proposed July 22, 2010 (75 FR 42672); and (2) The maximum 4th highest daily 8-hour.... Table 1--Monitoring Data for 8-Hour Ozone in the Philadelphia Area 4th Max 8-hr Site ID...

  8. 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...

  9. 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,...

  10. 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

    ... National Ambient Air Quality Standards for Ozone'', January 6, 2010 and 75 FR 2938 (January 19, 2010). On...-hour standard of 0.08 ppm \\1\\ (62 FR 33856). EPA revised the ozone standard after considering... standards by lowering the level for both to 0.075 ppm (73 FR 16436, Mar. 27, 2008). B. The Phoenix-Mesa...

  11. 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

    ... addition to being available in the docket, an electronic copy of this notice is also available on the World... 13211: Actions That Significantly Affect Energy Supply, Distribution, or Use I. National Technology... rulemaking (74 FR 2936). \\1\\ 74 FR 2936, January 16, 2009. III. This Action A. Classification of 8-Hour...

  12. 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

    ... quality standard (NAAQS). This extension is based in part on air quality data for the 4th highest daily 8..., EPA is approving the State's request as a direct final rule without prior proposal because the Agency... Street, Philadelphia, Pennsylvania 19103. Copies of the State submittal are available at...

  13. 8 HOUR OZONE DESIGN VALUE FOR 1998-2000

    EPA Science Inventory

    The Ozone design value is based on the average of the annual 4th highest dailsy 8-hour maximum over a 3-year period (1998-2000) in this case. This is a human health based metric. Ozone causes respiratory illness in humans.

  14. 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....

  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, 2010 CFR

    2010-07-01

    ... 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 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...

  18. 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...

  19. 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...

  20. 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... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas?...

  1. 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

    ... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas? The... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of...

  2. 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

    ... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas? The... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of...

  3. 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

    ... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas? The... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of...

  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

    ... 8-Hour Ozone National Ambient Air Quality Standard; Montana AGENCY: Environmental Protection Agency... the Clean Air Act (CAA) for the National Ambient Air Quality Standards (NAAQS) promulgated for ozone... Agency. (iii) The initials NAAQS mean or refer to National Ambient Air Quality Standards. (iv)...

  5. 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...

  6. 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

    ... 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 General... 40 Protection of Environment 2 2012-07-01 2012-07-01 false What are the requirements for an...

  7. 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

    ..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.908 What modeling and attainment demonstration requirements apply for... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection...

  8. 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

    ..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.908 What modeling and attainment demonstration requirements apply for... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection...

  9. 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

    ... 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 General... 40 Protection of Environment 2 2013-07-01 2013-07-01 false What are the requirements 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, 2014 CFR

    2014-07-01

    ..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.908 What modeling and attainment demonstration requirements apply for... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection...

  11. 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

    ... 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 General... 40 Protection of Environment 2 2014-07-01 2014-07-01 false What are the requirements for an...

  12. 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

    ... 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 General... 40 Protection of Environment 2 2011-07-01 2011-07-01 false What are the requirements for an...

  13. 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...

  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, 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...

  15. 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...

  16. 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... 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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

    ..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.917 What is the effective date of designation for the Las Vegas, NV, 8-hour... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection...

  2. 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...

  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, 2012 CFR

    2012-07-01

    ... 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...

  4. 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

    ... nonattainment area failed to attain the 1997 8-hour ozone national ambient air quality standard (NAAQS or... review of complete, quality assured and certified ambient air quality monitoring data for the 2007-2009 monitoring period that are available in the EPA Air Quality System (AQS) database. As a result of this...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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

    ... 1.36 Total 18.46 17.41 15.07 3.39 Table 2--Total NOX Emissions With MOVES2010a Mobile Emissions in... attainment of the 1997 8-hour ozone standard effective June 15, 2007 (72 FR 27648), and MOBILE6.2-based...(c) of the CAA. See the official release of the MOVES2010 emissions model (75 FR 9411-9414)...

  13. 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...

  14. 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,...

  15. 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,...

  16. 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...

  17. 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,...

  18. 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...

  19. 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...

  20. 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

  1. 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

    ... ambient air quality data for the 2009 ozone season. (See 76 FR 13289.) On June 4, 2010, EPA approved a..., and individuals with a pre-existing respiratory disease, such as asthma. On March 27, 2008 (73 FR... standard. B. The Baltimore Area On April 30, 2004 (69 FR 23951), EPA finalized its...

  2. 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

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Ohio; Lima 1997 8... the request by Ohio to revise the Lima, Ohio 1997 8-hour ozone maintenance air quality...

  3. 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... dated replacement pages for the Montana Interstate Transport Rule Declaration. The new set of pages were sent as replacement for the set of undated pages submitted earlier with the February 12, 2007 Record...

  4. 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... dated replacement pages for the Montana Interstate Transport Rule Declaration. The new set of pages were sent as replacement for the set of undated pages submitted earlier with the February 12, 2007 Record...

  5. 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

    ... 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...

  6. 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....

  7. 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

    ... 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 were.... These additional counties are: Barrow, Bartow, Carroll, Hall, Newton, Spalding, and Walton. See 69...

  8. 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.... See 56 FR 56694, November 6, 1991. \\4\\ Seven additional ``ring'' counties were added to the original 1... counties include: Barrow, Bartow, Carroll, Hall, Newton, Spalding, and Walton. See 69 FR 23857, April...

  9. 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

    ... is more protective than the previous 1-hour ozone standard (62 FR 38855) that was established by EPA in 1979. We revoked the 1-hour ozone standard effective June 15, 2005. See 40 CFR 50.9(b) and 69 FR...). See 69 FR 23857 (April 30, 2004).\\1\\ Ambient air quality monitoring data for the 3-year period...

  10. 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...

  11. 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

    ... 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...

  12. 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

    ... 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 51.913 - 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...

  14. 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...

  15. 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, OH/KY/IN... (tpd), for VOCs and NOx for the Ohio and Indiana portions of the Cincinnati, Ohio area are as...

  16. 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...

  17. 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...

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

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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...

  19. 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...

  20. 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.

  1. 77 FR 3720 - Determination of Failure To Attain the One-Hour Ozone Standard by 2007, Determination of Current...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-25

    ..., EPA reviewed ozone monitoring air quality data from the States, in accordance with 40 CFR 50.9, 40 CFR... Implement the 8-Hour Ozone National Ambient Air Quality Standard--Phase 1,'' referred to as the Phase 1 Rule... period). \\2\\ Final Rule to Implement the 8-Hour Ozone National Ambient Air Quality Standard--Phase 1,...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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 ...

  8. 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...

  9. 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...

  10. 40 CFR 51.906 - Redesignation to nonattainment following initial designations for the 8-hour NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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...

  11. 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...

  12. 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...

  13. 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...

  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. 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

    ...'' (66 FR 28355, May 22, 2001). This action merely approves state law as meeting Federal requirements and... 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,...

  17. 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

    ..., 2010 (75 FR 43114), EPA published a notice of proposed rulemaking (NPR) for the State of Maryland. The... Energy Supply, Distribution, or Use (66 FR 28355, May 22, 2001). This action merely approves State law as... 12866 (58 FR 51735, October 4, 1993), this action is not a ``significant regulatory action''...

  18. 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

    ... Nonattainment Area 4th Max 8-HR Site ID County/State Year (ppm) 24-003-0014 Anne Arundel, MD 2009 0.070 24-005.... Statutory and Executive Order Reviews Under Executive Order 12866 (58 FR 51735, October 4, 1993), this... Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use'' (66 FR 28355 (May...

  19. 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...

  20. 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... 12866 (58 FR 51735, October 4, 1993); Does not impose an information collection burden under...

  1. 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

    ... (69 FR 23951, April 30, 2004). The rule further provides that an area remains subject to these... National Association of Manufacturers; and (3) the American Petroleum Institute, American Chemistry Council.... \\4\\ 70 FR 30592 (May 26, 2005). In the second reconsideration rulemaking, we proposed and...

  2. 78 FR 28497 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Canton-Massillon 1997 8-Hour...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-15

    ... attainment of the 1997 8-hour ozone standard effective June 15, 2007, (72 FR 27648). MOBILE6.2-based budgets... the CAA. See the official release of the MOVES2010 emissions model (75 FR 9411-9414) for background... of MOVES2010 in March 2010 (75 FR 9411). Use of the MOVES model is required for regional...

  3. 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.

  4. 40 CFR 52.977 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the Baton Rouge 1-hour ozone nonattainment area has attained the 1-hour ozone National Ambient Air... determined that the Baton Rouge 8-hour ozone nonattainment area has attained the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS). Under the provisions of 40 CFR 51.918 this determination...

  5. 40 CFR 52.977 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the Baton Rouge 1-hour ozone nonattainment area has attained the 1-hour ozone National Ambient Air... determined that the Baton Rouge 8-hour ozone nonattainment area has attained the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS). Under the provisions of 40 CFR 51.918 this determination...

  6. 40 CFR 52.977 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the Baton Rouge 1-hour ozone nonattainment area has attained the 1-hour ozone National Ambient Air... determined that the Baton Rouge 8-hour ozone nonattainment area has attained the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS). Under the provisions of 40 CFR 51.918 this determination...

  7. 40 CFR 52.977 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the Baton Rouge 1-hour ozone nonattainment area has attained the 1-hour ozone National Ambient Air... determined that the Baton Rouge 8-hour ozone nonattainment area has attained the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS). Under the provisions of 40 CFR 51.918 this determination...

  8. 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...

  9. 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, 2010 CFR

    2010-07-01

    ... for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.907 For an area that... 40 Protection of Environment 2 2010-07-01 2010-07-01 false For an area that fails to attain the 8... the CAA? 51.907 Section 51.907 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  10. 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

    ... 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 standard...\\ See 62 FR 38856 (July 18, 1997). In 2008 we lowered the 8- hour ozone standard to 0.075 ppm. See 73...

  11. 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),...

  12. 40 CFR 52.2037 - Control strategy plans for attainment and rate-of-progress: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CFR 51.918, EPA has determined that Pittsburgh-Beaver Valley 8-hour ozone nonattainment area has...-hour ozone standard of 40 CFR 50.9: the attainment demonstration and reasonably available control... 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends...

  13. 40 CFR 52.2037 - Control strategy plans for attainment and rate-of-progress: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CFR 51.918, EPA has determined that Pittsburgh-Beaver Valley 8-hour ozone nonattainment area has...-hour ozone standard of 40 CFR 50.9: the attainment demonstration and reasonably available control... 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends...

  14. ACCOUNTABILITY WITHIN NEW OZONE STANDARDS

    EPA Science Inventory

    Over the past two decades, as part of the effort to develop the National Ambient Air Quality Standards (NAAQS), researchers have been using real human exposure data to help analyze the magnitude and extent of the risks from specific or multiple pollutants. Surrogates for exposur...

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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...

  16. Nocturnal stomatal conductance and ambient air quality standards for ozone

    NASA Astrophysics Data System (ADS)

    Musselman, Robert C.; Minnick, Tamera J.

    Vegetation response to ozone depends on ozone conductance into leaves and the defensive action inside the leaf. Ozone parameters currently used for air quality standards do not incorporate conductance or defensive components. Nighttime flux has often been ignored in ozone metrics relating to plant response, since ozone concentration and conductance are considered to be minimal at night. However, ozone concentration can remain relatively high at night, particularly in mountainous areas. Although conductance is lower at night than during the day for most plants, nocturnal conductance can result in considerable ozone flux into plants. Further, plants can be more susceptible to ozone exposure at night than during the daytime, a result of lower plant defenses at night. Any ozone metric used to relate air quality to plant response should use a 24 h ozone exposure period to include the nighttime exposures. It should also incorporate plant defensive mechanisms or their surrogate.

  17. A new ozone standard - The vapor pressure of ozone at liquid argon temperatures

    NASA Technical Reports Server (NTRS)

    Mauersberger, K.; Hanson, D.; Morton, J.

    1985-01-01

    The vapor pressure of ozone has been measured at liquid argon temperatures. At the normal boiling point of argon (-185.9 C) an ozone pressure of 0.0405 torr was obtained with an accuracy of + or - 1.5 percent. Increases and decreases in liquid argon temperatures raised and lowered the ozone vapor pressure, respectively. During the vapor pressure measurements the purity of ozone was monitored with a mass spectrometer. The proposed ozone standard will considerably improve the calibration of experiments for atmospheric research, the determination of absorption cross sections and other laboratory ozone studies.

  18. EFFICACY OF OZONE EXPOSURE INDICES IN THE STANDARD SETTING PROCESS

    EPA Science Inventory

    Determining the appropriate ozone exposure index for a secondary ambient air quality standard requires a consideration of the underlying biological basis for the response and a method of describing the temporal fluctuations in pollutant concentrations. An exposure index that adeq...

  19. 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.

  20. 75 FR 2938 - National Ambient Air Quality Standards for Ozone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ....gov/ttn/naaqs/standards/ozone/s_o3_cr_fr.html prior to the hearing. Verbatim transcripts of the... a reconsideration of the 2008 O 3 NAAQS final rule (73 FR 16436, March 27, 2008), which revised the... proposed rule (72 FR 37818, July 11, 2007) and the 2008 final rule (73 FR 16436). A....

  1. TRANSFER STANDARDS FOR THE CALIBRATION OF AMBIENT AIR MONITORING ANALYZERS FOR OZONE. TECHNICAL ASSISTANCE DOCUMENT

    EPA Science Inventory

    New EPA regulations (40 CFR Part 50, Appendix D) allow the use of transfer standards for the calibration of ambient ozone monitors. This document is a reference aid to help users select ozone transfer standards and reference them to a primary UV standard. It defines ozone transfe...

  2. 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

  3. 40 CFR 52.2037 - Control strategy plans for attainment and rate-of-progress: Ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CFR 51.918, EPA has determined that Pittsburgh-Beaver Valley 8-hour ozone nonattainment area has...-hour ozone standard of 40 CFR 50.9: the attainment demonstration and reasonably available control... Federal Register citations affecting § 52.2037, see the List of CFR Sections Affected, which appears...

  4. 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...

  5. 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...

  6. Development of KRISS standard reference photometer (SRP) for ambient ozone measurement

    NASA Astrophysics Data System (ADS)

    Lee, S.; Lee, J.

    2014-12-01

    Surface ozone has adverse impacts on human health and ecosystem. Accurate measurement of ambient ozone concentration is essential for developing effective mitigation strategies and understanding atmospheric chemistry. Korea Research Institute of Standards and Science (KRISS) has developed new ozone standard reference photometers (SRPs) for the calibration of ambient ozone instruments. The basic principle of the KRISS ozone SRPs is to determine the absorption of ultraviolet radiation at a specific wavelength, 253.7 nm, by ozone in the atmosphere. Ozone concentration is calculated by converting UV transmittance through the Beer-Lambert Law. This study introduces the newly developed ozone SRPs and characterizes their performance through uncertainty analysis and comparison with BIPM (International Bureau of Weights and Measures) SRP.

  7. 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... percent control. Subchapter 26 also regulates the VOC content/vapor pressure of surface-preparation...

  8. EMISSION INVENTORIES TO SUPPORT DEVELOPMENT OF PM2.5 AND 8-HOUR OZONE IMPLEMENTATION POLICIES

    EPA Science Inventory

    The product will be a set of historical and projected emission inventories. The projected inventories will represent a number of alternative regulatory scenarios. Inventories will be in the form required by CMAQ/Models-3 and other air quality models, and will be accompanied by n...

  9. 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... Barrow, Bartow, Carroll, Cherokee, Clayton, Cobb, Coweta, Dekalb, Douglas, Fayette, Forsyth,...

  10. 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

    ... Order 13045: Protection of Children from Environmental Health Risks and Safety Risks (62 FR 19885, April... Order 12898 (59 FR 7629, February 16, 1994), establishes federal executive policy on environmental... 0.12 parts per million (ppm) to 0.08 ppm (62 FR 38856). By statute, SIPs meeting the requirements...

  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

    ... Table 2--Total NOX Emissions With MOVES2010a Mobile Emissions in the Ohio portion of Wheeling West... effective June 15, 2007 (72 FR 27644). MOBILE6.2-based budgets for the Ohio portion of the area were... section 176(c) of the CAA. See the official release of the MOVES2010 emissions model (75 FR 9411-9414)...

  12. 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

    ... approved. For additional information, see the proposed rulemaking published on July 22, 2010 (75 FR 42672... the Act and EPA's regulations. Administrative Correction On August 3, 2010, 75 FR 45483, EPA took... Management and Budget under Executive Order 12866 (58 FR 51735, October 4, 1993); Does not impose...

  13. 75 FR 17915 - Agency Information Collection Activities; Proposed Collection; Comment Request; 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-08

    ... keeping necessary to maintain the rule. The rule was proposed on June 2, 2003, (68 FR 32802) and promulgated in two Phases: Phase 1 published on April 30, 2004, (69 FR 23951) and Phase 2 published on November 29, 2005 (70 FR 71612). The preamble to the proposed and final regulations addressed...

  14. 78 FR 45188 - Agency Information Collection Activities; Proposed Collection; Comment Request; 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-26

    ... the rule. The rule was proposed on June 2, 2003 (68 FR 32802), and promulgated in two Phases: Phase 1 published on April 30, 2004 (69 FR 23951), and Phase 2 published on November 29, 2005 (70 FR 71612). The... preamble to the final Phase 2 rule stated that an ICR would be prepared (70 FR 71692). The rule...

  15. 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

    ...-Hour Ozone National Ambient Air Quality Standard--Phase 1, 69 FR 23951 (April 30, 2004). III. What... 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......

  16. Ozone flux to vegetation and its relationship to plant response and ambient air quality standards

    NASA Astrophysics Data System (ADS)

    Musselman, Robert C.; Massman, William J.

    The National Ambient Air Quality Standard (NAAQS) for ozone is based on occurrences of the maximum 8 h average ambient ozone concentration. However, biologists have recommended a cumulative ozone exposure parameter to protect vegetation. In this paper we propose a third alternative which uses quantifiable flux-based numerical parameters as a replacement for cumulative ambient parameters. Herein we discuss the concept of ozone flux as it relates to plant response and the NAAQS, and document information needed before a flux-based ozone NAAQS for vegetation can be implemented. Additional research is needed in techniques for determining plant uptake and in the quantification of plant defensive mechanisms to ozone. Models which include feedback mechanisms should be developed to relate ozone flux, loading, and detoxification with photosynthesis and plant productivity.

  17. 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

    ... 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 of the national 1-hour primary and secondary ambient air quality standards for ozone measured by...

  18. 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

    ... 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 of the national 1-hour primary and secondary ambient air quality standards for ozone measured by...

  19. 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

    ... 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...

  20. 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

    ... 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...

  1. 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...

  2. 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

    ... 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 of the national 1-hour primary and secondary ambient air quality standards for ozone measured by...

  3. 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

    ... 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 of the national 1-hour primary and secondary ambient air quality standards for ozone measured by...

  4. 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...

  5. Ozone

    MedlinePlus

    ... Earth's surface. It shields us from the sun's ultraviolet rays. Part of the good ozone layer is ... enough good ozone, people may get too much ultraviolet radiation. This may increase the risk of skin ...

  6. 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 ...

  7. 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... promulgation of a new or revised national ambient air quality standard for any pollutant under section 109, the... a national ambient air quality standard, the Administrator shall promulgate the designations of...

  8. 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 ...

  9. 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...

  10. 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.

  11. 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...

  12. 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....

  13. A conceptual ozone dose-response model to develop a standard to protect vegetation

    NASA Astrophysics Data System (ADS)

    Massman, William J.; Musselman, Robert C.; Lefohn, Allen S.

    The present air quality standard to protect vegetation from ozone is based on a measured concentration (i.e., exposure) rather than on plant uptake rates (or dose). Proposed exposure-based standards have led to concerns about the appropriateness of chamber studies. There has also been some debate about the importance of the diel phase difference between plant conductance and ozone concentration in assessing the potential for plant damage. In this paper, we use physical reasoning based on (i) plant defenses and (ii) general resistance concepts of dry deposition to derive a suggested general form of a dose-based standard. The dose-based standard is then related to the more traditional exposure-based standard. Although we develop the model in terms of plant injury, we also discuss how the model can be extended to include damage, which historically has been the focus of air quality standards. With this new dose-based approach, we clarify some of the issues concerning chambers and the interaction of the daily cycles of ozone concentration and plant stomatal conductance. We further demonstrate that (i) weighted fluxes can be used as a surrogate for plant defenses, (ii) injury or damage to vegetation is more likely to be correlated with a dose-based index that differentially weights ambient ozone concentration or plant uptake rates than one which does not, (iii) the potential for ozone injury or damage to plants can occur throughout the day, and (iv) when assessing the potential for plant damage, a differentially weighted flux-based standard is likely to be more precise and more discriminating than a cumulative ozone-based exposure index. Finally, because our basic premise relies on plant defensive mechanisms, we outline areas of research that are necessary before a dose-based standard can be implemented.

  14. The path toward clean air: implementing new standards for ozone and fine particles

    SciTech Connect

    Lydia Wegman; Erika Sasser

    2005-04-01

    Many areas in the United States have air pollution that exceeds the levels allowed by the U.S. Environmental Protection Agency (EPA) under its revised National Ambient Air Quality Standards for ozone and fine particles. This article provides an overview of the steps EPA and states are taking to implement the new standards. 17 refs., 3 figs., 2 tabs.

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 77 FR 64036 - Determination of Attainment of the 1-Hour Ozone National Ambient Air Quality Standards in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-18

    ...EPA is determining that the Sacramento Metro 1-hour ozone nonattainment area (Sacramento Metro Area) has attained the revoked National Ambient Air Quality Standard (1-hour ozone NAAQS or standard), and to exclude certain 2008 data caused by wildfire exceptional events. These air quality determinations were proposed in conjunction with a proposed determination to terminate the State of......

  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

    ...This rule establishes initial air quality designations for most areas in the United States, including areas of Indian country, for the 2008 primary and secondary national ambient air quality standards (NAAQS) for ozone. The designations for several counties in Illinois, Indiana, and Wisconsin that the EPA is considering for inclusion in the Chicago nonattainment area will be designated in a......

  1. 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...

  2. 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

    ... max 8-hour Conc. (ppm) 4th Highest daily max 8-hour Conc. (ppm) 5th Highest daily max 8-hour Conc.... (ppm) 3rd Highest daily max 8-hour Conc. (ppm) 4th Highest daily max 8-hour Conc. (ppm) 5th...

  3. 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.

  4. Motor cortex excitability changes within 8 hours after ischaemic stroke may predict the functional outcome.

    PubMed

    Di Lazzaro, V; Oliviero, A; Profice, P; Saturno, E; Pilato, F; Tonali, P

    1999-06-01

    Motor evoked potentials after magnetic transcranial stimulation and the excitability of the motor cortex to increasing magnetic stimulus intensities were evaluated in six patients with hemiparesis after ischaemic stroke within 8 hours after stroke. The latencies of motor evoked potentials were normal in all patients. After stimulation of the ischaemic hemisphere we obtained responses comparable with the contralateral ones in two patients (mean NIH score 2 (SD 0)) and this group was completely asymptomatic after 15 days (NIH score 0). In four patients the excitability of the motor cortex involved by the ischaemia was reduced and magnetic motor threshold was higher than that of the spared motor cortex. This finding was associated with a poor motor recovery and the NIH score after 15 days was unchanged (NIH score 1.75 (SD 1.5)). The present data suggest that the evaluation of the excitability of motor cortex may offer a mean of predicting functional outcome following stroke. PMID:10461555

  5. 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...

  6. 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

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Virginia; Adoption... available on the Internet. If you ] submit an electronic comment, EPA recommends that you include your name... statute. Certain other material, such as copyrighted material, is not placed on the Internet and will...

  7. 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...

  8. 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... are provided in Table 1: Table 1--Dallas-Fort Worth Reasonable Further Progress NOX and VOC MVEBs...

  9. 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... ceiling for the regional transportation network. The MVEB is provided in Table 1: Table 1--Baton Rouge...

  10. 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

    ... Implementation Plan (SIP) on June 18, 2009, by James B. Martin, Director, Colorado Department of Public Health...) 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...

  11. 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... Court of Appeals for the District of Columbia Circuit (DC Circuit) ruled that submitted SIPs cannot...

  12. 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...

  13. Plasma total antioxidant status in horses after 8-hours of road transportation

    PubMed Central

    2013-01-01

    Background The aim of this study was to investigate the effects of 8-hour road transport on plasma total antioxidant status (PTAS) and general clinical appearance in horses. Findings The study was conducted on a group of 60 horses of different breeds aged from 4 to 10 years. Venous blood was collected and a clinical examination was performed immediately before loading horses onto trailers for an 8 hour transport (I), immediately after unloading them from the trailer (II), and after a subsequent 24 hour stall rest (III). The ferric-reducing ability of plasma (FRAP) was used to determine PTAS. The transportation significantly increased respiratory and heart rates. The average PTAS increased during the three subsequent samplings: I: 170 ± 77 (μmol/l) II: 204 ± 70 (μmol/l) III: 221 ± 74 (μmol/l). Conclusion Long-distance transport increased the PTAS horses, as well as respiratory and heart rates. PMID:23945316

  14. Modal Sequencing in an 8-hour GMRT Observation of Pulsar B1822-09

    NASA Astrophysics Data System (ADS)

    Latham, C.; Mitra, D.; Rankin, J.

    2012-12-01

    The research presented here examines an 8-hour observation of pulsar B1822-09, acquired with the Giant Metrewave Radio Telescope. B1822-09 is known to exhibit two stable emission modes, the B mode, where the precursor (PC) “turns on”, and the Q mode, which is defined by interpulse (IP) emission. These emission modes are like pulsar “personalities.” Our analyses have shown that the pulsar's two modes are not as “pure” as previously thought, in that PC emission is sometimes seen in the B mode, IP emission in Q-mode intervals and near transitions PS and IP emission can occur simultaneously. Further, in this long observation, the Q mode shows periodic modulation near 46.6±1.0 rotation periods that modulates both the main pulse IP. We find indications that this represents a P3 associated with a subbeam carousel, and that its circulation time is thrice this value. Moreover, we detected a B-mode modulation at 70±3 that appears to have an odd-even character—thus both cycles are commensurate at around 140 rotation periods.

  15. 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 ...

  16. 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

  17. Long-term changes in the total ozone mapping spectrometer relative to world primary standard Dobson spectrometer 83

    SciTech Connect

    McPeters, R.D. ); Komhyr, W.D. )

    1991-02-20

    The authors have examined the stability of the calibration of the Nimbus 7 solar backscatter ultraviolet (SBUV) and total ozone mapping spectrometer (TOMS) instruments by comparing their ozone measurements with those made by a single, very stable Dobson instrument: the world primary standard Dobson spectrometer number 83. Measurements of ozone made with instrument 83 at Mauna Loa observatory in eight summers between 1979 and 1989 were compared with coincident TOMS ozone measurements. The comparison shows that relative to instrument 83, ozone measured by TOMS (and SBUV) was stable between 1979 and approximately 1983, had decreased by 3% by 1986, and had decreased by almost 7% by 1989. A similar time dependence is seen when data from an ensemble of 39 Dobson stations throughout the world is compared with TOMS over the period 1979-1987. The most likely reason for the relative drift is that the diffuser plate used by both SBUV and TOMS to measure solar flux has suffered an uncorrected wavelength dependent degradation, with most of the degradation occurring after 1983. The recently released version 6 TOMS data, corrected using the internal pair justification technique, show almost no drift relative to Dobson instrument 83. The authors conclude from these comparisons that accurate measurements of long-term global ozone change will require a coherent system incorporating both ground based and satellite based ozone measurements.

  18. Long-term changes in the total ozone mapping spectrometer relative to world primary standard Dobson spectrometer 83

    NASA Technical Reports Server (NTRS)

    Mcpeters, Richard D.; Komhyr, W. D.

    1991-01-01

    The stability of the calibration of the Nimbus 7 solar backscatter UV (SBUV) and total ozone mapping spectrometer (TOMS) instruments by comparing their ozone measurements with those made by a single, very stable Dobson instrument: the world primary standard Dobson spectrometer number 83. Measurements of ozone made with instrument 83 at Mauna Loa observatory in eight summers between 1979 and 1989 were compared with coincident TOMS ozone measurements. The comparison shows that relative to instrument 83, ozone measured by TOMS (and SBUV) was stable between 1979 and approximately 1983, had decreased by 3 percent by 1986, and had decreased by almost 7 percent by 1989. A similar time dependence is seen when data from an ensemble of 39 Dobson stations throughout the world is compared with TOMS over the period 1979-1987. The most likely reason for the relative drift is that the diffuser plate used by both SBUV and TOMS to measure solar flux has suffered an uncorrected wavelength-dependent degradation, with most of the degradation occurring after 1983. The recently released version 6 TOMS data, corrected using the internal 'pair justification' technique, show almost no drift relative to Dobson instrument 83. Accurate measurements of long-term global ozone change will require a coherent system incorporating both ground-based and satellite-based ozone measurements.

  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. PMID:25857292

  20. 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...

  1. 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... table for the 1997 ozone NAAQS. See 77 FR at 8201-02. \\7\\ The upper thresholds of the Marginal,...

  2. 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...

  3. 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...

  4. 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...

  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 52.2125 - 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...

  7. 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...

  8. 40 CFR 52.1779 - 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 4 2013-07-01 2013-07-01 false Control strategy: Ozone. 52.1779... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the...

  9. A mid-latitude ozone model for the US standard atmosphere, 1975 (summary)

    NASA Technical Reports Server (NTRS)

    Krueger, A. J.; Minzner, R. A.

    1974-01-01

    A mid-latitude, Northern-Hemisphere model of the daytime ozone distribution in the troposphere, stratosphere, and lower mesosphere was constructed. Data from rocket soundings in the latitude range 45 deg N + or - 15 deg, results of balloon soundings at altitudes from 41 to 47 deg N, and latitude gradients from satellite ozone observations were combined to produce estimates of the annual mean ozone concentration and its variability at heights to 72 km for an effective latitude of 45 deg N. The model is a revision, for heights above 26 km, of the tentative Mid-Latitude Ozone Model.

  10. Scientific basis of the national ambient air quality standards for ozone: How do new discoveries and other concerns modify public health risks and expected benefits?

    SciTech Connect

    Vostal, J.J.; Heuss, J.M.; Paul, R.T.; Pezda, S.A.; Ball, J.C.; Wimette, H.J.

    1999-07-01

    The US EPA, in their recent review of the ozone NAAQS, acknowledged that substantial uncertainties exist with respect to the determination of public health risks due to ambient ozone. In particular, the uncertainties focus on considerable differences of opinion among scientists for the possible health effects at ozone levels near the new 8-hr. ozone National Air Quality Standard (NAAQS) of 0.08 ppm. Information on health or vegetation effects of low ambient ozone levels has been scarce, or extrapolated from studies using levels that are substantially above the new standard level. Uncertainties fall into three categories: (1) the extent of the adversity of public health endpoints; (2) the probability of adverse exposures; and (3) the impact of background levels on the achievability of the new standard. More specifically: (A) Public health effects of low ozone levels have thus far depended primarily on compromised pulmonary function as the biological endpoint of the greatest clinical significance. However, research data published after the standard was promulgated show that the ozone-induced effects represent more a physiological defense mechanism than an adverse effect of low ambient ozone concentrations. In light of these new findings, the alleged ozone action represents only a decline in pulmonary function test performance and not in the vital function of the lungs. This new interpretation not only eliminates the adverse character of pulmonary function decrements, but also largely modifies the proposed estimates of public health risks. (B) Public health risk assessments have indicated that even with compliance of the 1-hour ozone standard, the chances for US populations to encounter an adverse ozone exposure have been practically eliminated.

  11. 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...

  12. 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...

  13. 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...

  14. 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

    ... 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...

  15. 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...

  16. 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.

  17. Emission reductions and urban ozone responses under more stringent US standards

    NASA Astrophysics Data System (ADS)

    Downey, Nicole; Emery, Chris; Jung, Jaegun; Sakulyanontvittaya, Tanarit; Hebert, Laura; Blewitt, Doug; Yarwood, Greg

    2015-01-01

    We use a photochemical grid model instrumented with the high-order Decoupled Direct Method (HDDM) to evaluate the response of ozone (O3) to reductions in US-wide anthropogenic emissions, and to estimate emission reductions necessary to meet more stringent National Ambient Air Quality Standards (NAAQS) for O3. We simulate hourly O3 response to nationwide reductions in nitrogen oxides (NOx) and volatile organic compound (VOC) emissions throughout 2006 and compare O3 responses in 4 US cities: Los Angeles, Sacramento, St. Louis, and Philadelphia. We compare O3 responses between NOx-rich, O3-inhibited urban core sites and NOx-sensitive, higher O3 suburban sites and analyze projected O3 frequency distributions, which can be used to drive health effect models. We find that 2006 anthropogenic NOx and VOC emissions must be reduced by 60-70% to reach annual 4th highest (H4) maximum daily 8-h (MDA8) O3 of 75 ppb (the current US standard) in Sacramento, St. Louis, and Philadelphia, and by 80-85% to reach an H4 MDA8 of 60 ppb. Los Angeles requires larger emissions reductions and achieves an H4 MDA8 of 75 ppb with 92% reductions and 60 ppb with 97% reductions. As emissions are reduced, hourly and MDA8 frequency distributions tend toward mid-level background distributions. Mid-level O3 exposure is an important driver of O3 health impacts calculated by epidemiological models. A significant fraction (at least 48%) of summertime integrated MDA8 O3 at all sites remains after complete elimination of US anthropogenic NOx and VOC emissions, implying that mid-level O3 exposure due to background will become more important as domestic precursor emissions are controlled.

  18. 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.

  19. A study of interferences in ambient ozone monitors

    SciTech Connect

    Kleindienst, T.E.; McIver, C.D.; Ollison, W.M.

    1997-12-31

    Recently proposed EPA revisions to the ozone ambient air quality standards change allowable ozone levels from 120 ppbv (1-hour average) to 70-90 ppbv (8-hour average). Accordingly, the relative importance of potential interferences in currently deployed ethylene-chemiluminescence and ultraviolet (UV) absorption monitors may be increased. UV absorption monitors predominate US monitoring networks and operate in a dual channel mode, requiring a scrubber to selectively remove ozone from other UV absorbing species. However, these scrubbers may also remove aromatic species with UV absorption coefficients at 254 run comparable to ozone that could constitute potential interferants. The interference potential for only a few of these compounds has been determined. Additional representative organic precursor species likely to be present under polluted conditions (e.g., C{sub 8}-C{sub 9} aromatic hydrocarbons and their nitroaromatic and phenolic derivatives) have been tested as UV interferants in this study. The removal and reentrainment of aromatic pollutants on ozone scrubbers used in UV monitors is highly dependent on the relative humidity in the system. Raising the temperature of the scrubber does not improve its interferant transmission under dry conditions and increases the retention of potential interferants under humid conditions. Reduced sulfur compounds such as CS{sub 2} do not appear to be interferants for the chemiluminescence monitor.

  20. Standardizing Interfaces for External Access to Data and Processing for the NASA Ozone Product Evaluation and Test Element (PEATE)

    NASA Technical Reports Server (NTRS)

    Tilmes, Curt A.; Fleig, Albert J.

    2008-01-01

    NASA's traditional science data processing systems have focused on specific missions, and providing data access, processing and services to the funded science teams of those specific missions. Recently NASA has been modifying this stance, changing the focus from Missions to Measurements. Where a specific Mission has a discrete beginning and end, the Measurement considers long term data continuity across multiple missions. Total Column Ozone, a critical measurement of atmospheric composition, has been monitored for'decades on a series of Total Ozone Mapping Spectrometer (TOMS) instruments. Some important European missions also monitor ozone, including the Global Ozone Monitoring Experiment (GOME) and SCIAMACHY. With the U.S.IEuropean cooperative launch of the Dutch Ozone Monitoring Instrument (OMI) on NASA Aura satellite, and the GOME-2 instrumental on MetOp, the ozone monitoring record has been further extended. In conjunction with the U.S. Department of Defense (DoD) and the National Oceanic and Atmospheric Administration (NOAA), NASA is now preparing to evaluate data and algorithms for the next generation Ozone Mapping and Profiler Suite (OMPS) which will launch on the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP) in 2010. NASA is constructing the Science Data Segment (SDS) which is comprised of several elements to evaluate the various NPP data products and algorithms. The NPP SDS Ozone Product Evaluation and Test Element (PEATE) will build on the heritage of the TOMS and OM1 mission based processing systems. The overall measurement based system that will encompass these efforts is the Atmospheric Composition Processing System (ACPS). We have extended the system to include access to publically available data sets from other instruments where feasible, including non-NASA missions as appropriate. The heritage system was largely monolithic providing a very controlled processing flow from data.ingest of

  1. 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

  2. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Ozone. 52.582...

  3. 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... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Ozone. 52.582...

  4. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Ozone. 52.582...

  5. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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

  6. 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...

  7. 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...

  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..., Kalmiopsis Wilderness Area, Mountain Lakes Wilderness Area, Gearhart Mountain Wilderness Area, Crater...

  9. 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..., Kalmiopsis Wilderness Area, Mountain Lakes Wilderness Area, Gearhart Mountain Wilderness Area, Crater...

  10. 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..., Kalmiopsis Wilderness Area, Mountain Lakes Wilderness Area, Gearhart Mountain Wilderness Area, Crater...

  11. 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

  12. 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

  13. OZONE AMBIENT AIR QUALITY STANDARD HAS BENEFICIAL EFFECT ON PONDEROSA PINE IN CALIFORNIA

    EPA Science Inventory

    Ambient air quality standards and control strategies are implemented to protect humans and vegetation from adverse effects. However, to date there has not been a simple and objective method to determine if the standards and resultant control strategies have reduced O3 impacts on ...

  14. AN APPROACH FOR EVALUATING THE EFFECTIVENESS OF VARIOUS OZONE AIR QUALITY STANDARDS FOR PROTECTING TREES

    EPA Science Inventory

    We demonstrate an approach for evaluating the level of protection attained using a variety of forms and levels of past, current, and proposed Air Quality Standards (AQSs). The U.S. Clean Air Act requires the establishment of ambient air quality standards to protect health and pub...

  15. Crop loss assessment for California: modeling losses with different ozone standard scenarios.

    PubMed

    Olszyk, D M; Thompson, C R; Poe, M P

    1988-01-01

    Crop yield losses were estimated for ambient O3 concentrations and for a series of potential O3 air quality standards for California, including the current statewide 1-h oxidant (O3) standard of 0.10 ppm (196 microg m(-3)), 12-h growing season averages, and other models. A model for statewide losses was developed using hourly O3 data for all sites in the State, county crop productivity data, and available O3 concentration-yield loss equations to determine potential yield losses for each crop in each county in California for 1984. Losses were based on comparison to an estimated background filtered air concentration of 0.025 or 0.027 ppm, for 12 or 7 h, respectively. Potential losses due to ambient air in 1984 were estimated at 19% to 25% for dry beans, cotton, grapes, lemons, onions, and oranges. Losses of 5% to 9% were estimated for alfalfa and sweet corn. Losses of 4% or less were estimated for barley, field corn, lettuce, grain sorghum, rice, corn silage, spinach, strawberries, sugar beets, fresh tomatoes, processing tomatoes, and wheat. Implementation of either a modified rollback to meet the current 1 h California O3 standard (0.10 ppm) or a three-month, 12-h growing season average of 0.045 ppm was necessary to produce large reductions in potential crop losses. PMID:15092558

  16. Standardization of the Definitions of Vertical Resolution and Uncertainty in the NDACC-archived Ozone and Temperature Lidar Measurements

    NASA Technical Reports Server (NTRS)

    Leblanc, T.; Godin-Beekmann, S.; Payen, Godin-Beekmann; Gabarrot, Franck; vanGijsel, Anne; Bandoro, J.; Sica, R.; Trickl, T.

    2012-01-01

    The international Network for the Detection of Atmospheric Composition Change (NDACC) is a global network of high-quality, remote-sensing research stations for observing and understanding the physical and chemical state of the Earth atmosphere. As part of NDACC, over 20 ground-based lidar instruments are dedicated to the long-term monitoring of atmospheric composition and to the validation of space-borne measurements of the atmosphere from environmental satellites such as Aura and ENVISAT. One caveat of large networks such as NDACC is the difficulty to archive measurement and analysis information consistently from one research group (or instrument) to another [1][2][3]. Yet the need for consistent definitions has strengthened as datasets of various origin (e.g., satellite and ground-based) are increasingly used for intercomparisons, validation, and ingested together in global assimilation systems.In the framework of the 2010 Call for Proposals by the International Space Science Institute (ISSI) located in Bern, Switzerland, a Team of lidar experts was created to address existing issues in three critical aspects of the NDACC lidar ozone and temperature data retrievals: signal filtering and the vertical filtering of the retrieved profiles, the quantification and propagation of the uncertainties, and the consistent definition and reporting of filtering and uncertainties in the NDACC- archived products. Additional experts from the satellite and global data standards communities complement the team to help address issues specific to the latter aspect.

  17. 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

  18. Evaluation of phytotoxic elements, trace elements and nutrients in a standardized crop plant, irrigated with raw wastewater treated by APT and ozone.

    PubMed

    Orta de Velásquez, M T; Rojas-Valencia, M N; Reales-Pineda, A C

    2006-01-01

    This project studied the benefits of applying Advanced Primary Treatment (APT) and ozone (O3) to raw wastewater destined for reuse in agriculture. The ozone was applied directly to raw wastewater, as well as to wastewater already treated with APT, and the results compared against a control sample of potable water. The experimental conditions that reported the best results was wastewater treated with O3 (at a dose of 4.8 mg/L, at pH 7, temperature 23 degrees C, for 1 hr), given that it met standards in force in Mexico with regard to micro-organism and heavy metal content. Under these conditions, after 15 min of ozonation, 100% destruction of the following bacteria was observed: V. cholerae, S. typhi as well as total and faecal coliforms. Destruction of helminth eggs and Giardia sp. took one hour. No phytotoxic elements or heavy metals were found. The balance of nutrients N:P:K (300:100:200 mg/kg) required for lettuce growth, was found in wastewater subjected to both treatment plans. However, ozone favoured the nitrification and assimilation of the nutrients, by contributing oxygen to the soil. Therefore, these conditions produced the greatest lettuce growth, the entire plant averaging 38 cm in length and 125 g. in weight. Moreover, a better appearance of the leaves was also noted. PMID:17302317

  19. 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.

  20. 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.

  1. 40 CFR 52.523 - Control strategy: Ozone

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...)(2)(J). A FIP is currently in place and approved for Florida at 40 CFR 52.37 for these requirements... 52.523 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED.... EPA is disapproving portions of Florida's infrastructure SIP for the 1997 8-hour ozone NAAQS...

  2. 40 CFR 52.523 - Control strategy: Ozone

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...)(2)(J). A FIP is currently in place and approved for Florida at 40 CFR 52.37 for these requirements... 52.523 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED.... EPA is disapproving portions of Florida's infrastructure SIP for the 1997 8-hour ozone NAAQS...

  3. 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...

  4. Ozone from Wildfires: Peering through the Smog

    NASA Astrophysics Data System (ADS)

    Jaffe, D. A.; Baylon, P.; Wigder, N. L.; Collier, S.; Zhou, S.; Zhang, Q.; Alvarado, M. J.

    2014-12-01

    In the western US, many areas are near the current air quality standard for O3. Yet there is substantial inter-annual variability (IAV) in the number of days that exceed the O3 air quality threshold (currently 75 ppbv for an 8-hour average). We propose that wildfires are the dominant cause for this IAV. However there are large uncertainties around O3 production from wildfires due to numerous complicating factors. Ozone formation in wildfire plumes differs substantially from urban O3 production in several ways: substantial variations in the emissions, much larger aerosol loadings, a much greater variety of reactive and oxygenated VOCs, rapid and substantial formation of PAN and very different sources of HOx in the plume. These factors make it challenging to model wildfire impacts on photochemistry in the usual way. In this presentation we will show examples of three common situations based on data from the Mt. Bachelor Observatory: Rapid O3 formation (within one day) in a wildfire plume. Slow, but substantial, O3 formation (over days to a week) in a wildfire plume. No detectable O3 formation in a wildfire plume. We will interpret these results with respect to the observed NOy mixing ratios, the photochemical environment, the combustion efficiency, the plume transport and other factors and suggest some key experiments and modeling studies that can help further our understanding of wildfire O3 production.

  5. Ozone in the Atmosphere: II. The Lower Atmosphere.

    ERIC Educational Resources Information Center

    Phillips, Paul; Pickering, Pam

    1991-01-01

    Described are the problems caused by the increased concentration of ozone in the lower atmosphere. Photochemical pollution, mechanisms of ozone production, ozone levels in the troposphere, effects of ozone on human health and vegetation, ozone standards, and control measures are discussed. (KR)

  6. 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.

  7. Historical trends and ozone forecasting for urban regions of South Texas using statistical and heuristic techniques

    NASA Astrophysics Data System (ADS)

    Brown, Ronald K.

    . Ideally, the models should be developed using an optimum quantity of data and input parameters. Findings from this study indicate that only two years of data would be sufficient to develop a model instead of using large quantities of data. The analyses of trends in observed data is important to understand the ozone formation and identify the periods of high ozone concentrations in a region. Statistical Regression Analysis and Artificial Neural Networks models were developed to forecast high ozone episodes of Corpus Christi, San Antonio and Victoria. The predictive capabilities of these models were compared to determine their accuracy in forecasting daily maximum eight-hour ozone and peak one-hour ozone concentration by different model evaluation statistics. Results of the study indicated that both models were able to capture trends in ozone time series, but they were unable to accurately forecast peak ozone values. Between the two models, the performance of the Statistical Analysis model LR - RMSE averages ranged from 13.55 to 15.96 and the Artificial Neural Networks model MLP - RMSE averages ranged from 12.56 to 14.96, there seems to be very little difference in the forecasting capabilities. Also, it should be noted that according to forecasting skill proficiency, the 8-hour ozone standard provided the highest probability of detection of a high ozone forecast than did the 1-hour standard. There is still a degree of uncertainty associated with the result of the findings concerning the models ability to make accurate forecast. Previous studies have also noted that the difference in the performance superiority of one modeling technique over the other is suspect. Where the skill proficiency of one model fails the other may succeed and vice versa.

  8. Solving the Tulsa ozone problem

    SciTech Connect

    Wagner, K.K.; Wilson, J.D.; Gibeau, E.

    1998-12-31

    Local governments and interested parties in Tulsa, Oklahoma are planning actions to keep Tulsa in compliance with the ozone ambient air quality standard. Based on recent data Tulsa exceeds the new eight hour average national ambient air quality standard for ozone and occasionally exceeds the previous one hour standard. Currently, Tulsa is in attainment of the former one-hour ozone standard. The first planning step is to integrate the existing information about Tulsa`s ozone problem. Prior studies of Tulsa ozone are reviewed. Tulsa`s recent air quality and meteorological monitoring are evaluated. Emission inventory estimates are assessed. Factors identified with Tulsa`s ozone problem are the transport of ozone and precursor gases, a possible role for biogenic emissions, and a simplistic ozone forecasting method. The integration of information found that current air quality and meteorological monitoring is meager. Observations of volatile organic compounds and NO{sub y} are absent. Prior intensive studies in 1977 and 1985 are more than ten years old and lack relevance to today`s problem. Emission inventory estimates are scarce and uncertain. The current knowledge base was judged inadequate to properly characterize the present ozone problem. Actions are recommended to enlarge the information base to address Tulsa`s ozone problem.

  9. Spatio-temporal modeling for real-time ozone forecasting

    PubMed Central

    Paci, Lucia; Gelfand, Alan E.; Holland, David M.

    2013-01-01

    The accurate assessment of exposure to ambient ozone concentrations is important for informing the public and pollution monitoring agencies about ozone levels that may lead to adverse health effects. High-resolution air quality information can offer significant health benefits by leading to improved environmental decisions. A practical challenge facing the U.S. Environmental Protection Agency (USEPA) is to provide real-time forecasting of current 8-hour average ozone exposure over the entire conterminous United States. Such real-time forecasting is now provided as spatial forecast maps of current 8-hour average ozone defined as the average of the previous four hours, current hour, and predictions for the next three hours. Current 8-hour average patterns are updated hourly throughout the day on the EPA-AIRNow web site. The contribution here is to show how we can substantially improve upon current real-time forecasting systems. To enable such forecasting, we introduce a downscaler fusion model based on first differences of real-time monitoring data and numerical model output. The model has a flexible coefficient structure and uses an efficient computational strategy to fit model parameters. Our hybrid computational strategy blends continuous background updated model fitting with real-time predictions. Model validation analyses show that we are achieving very accurate and precise ozone forecasts. PMID:24010052

  10. 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.

  11. Ground-level ozone in Alberta

    SciTech Connect

    Sandhu, H.S.

    1999-11-01

    This literature review on ground-level ozone in Alberta begins with introductory sections on the precursors and products of ozone formation, the chemistry and meteorology of ozone, and atmospheric ozone models. The subsequent section reviews ozone data from ambient air quality monitoring stations in Alberta. The final section discusses trends in ozone concentrations in urban and rural areas of Alberta, human and environmental health effects of ozone, proposed national ambient objectives and Canada-wide standards for ground-level ozone, and options for an ozone concentration standard for Alberta. Appendices include an outline of air pollutant monitoring methods used in Alberta, lists of monitoring stations, and tables of monitoring results for nitrogen oxides, total hydrocarbons, and volatile organic compounds at Calgary and Edmonton sites.

  12. Ground-level ozone in Alberta

    SciTech Connect

    Sandhu, H.S.

    1999-01-01

    This literature review on ground-level ozone in Alberta begins with introductory sections on the precursors and products of ozone formation, the chemistry and meteorology of ozone, and atmospheric ozone models. The subsequent section reviews ozone data from ambient air quality monitoring stations in Alberta. The final section discusses trends in ozone concentrations in urban and rural areas of Alberta, human and environmental health effects of ozone, proposed national ambient objectives and Canada-wide standards for ground-level ozone, and options for an ozone concentration standard for Alberta. Appendices include an outline of air pollutant monitoring methods used in Alberta, lists of monitoring stations, and tables of monitoring results for nitrogen oxides, total hydrocarbons, and volatile organic compounds at Calgary and Edmonton sites.

  13. OZONE MULTI-YEAR PLAN

    EPA Science Inventory

    The tropospheric ozone research program addresses not only ozone, but other criteria pollutants such as SO2, nitrogen dioxide, carbon monoxide, and lead. It focuses on developing tools to help with implementation of National Ambient Air Quality Standards (NAAQS), such as improvin...

  14. 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

  15. Dose-response study of healthy, heavily exercising men exposed to ozone at concentrations near the ambient air quality standard

    SciTech Connect

    Linn, W.S.; Avol, E.L.; Shamoo, D.A.; Spier, C.E.; Valencia, L.M.; Venet, T.G.; Fischer, D.A.; Hackney, J.D.

    1986-07-01

    Twenty-four healthy, well-conditioned young adult male volunteers, free of asthma or clinical respiratory allergies, were exposed to purified air containing ozone (O3) at 0.16, 0.14, 0.12, 0.10, 0.08, and 0.00 part per million (ppm). Exposures were separated by 2-week intervals, occurred in random order, and lasted 2 hours each. Temperature was 32 +/- 1/sup 0/C and relative humidity was 38 +/- 3%, simulating Los Angeles area smog conditions. Subjects exercised 15 minutes of each half hour, attaining ventilation rates averaging 68 L/min (approximately 35 L/min per m2 body surface area). Lung function was measured pre-exposure and after 1 hr and 2 hr of exposure. Airway responsiveness to a cold-air challenge was measured immediately following the 2-hr exposure. Symptoms were recorded before, during, and for one-week periods following exposures. For the group as a whole, no meaningful untoward effects were found except for a mild typical respiratory irritant response after 2 hr exposure to 0.16 ppm O3. Two individual subjects showed possible responses at 0.14 ppm, and one of them also at 0.12 ppm. In comparison to some previous investigations, this study showed generally less response to O3. The comparative lack of response may relate to the favorable clinical status of the subjects, the pattern of exercise during exposure, or some other factor not yet identified.

  16. The effect of the Standard Nomenclature for Air Pollution (SNAP) categories on ozone and PM2.5 concentrations over Europe

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

    The objective of this study is to estimate the contribution of different anthropogenic emission sources on ozone and PM2.5 concentrations over Europe since anthropogenic activities (and the related emissions) are the reason of air quality degradation. Gridded yearly averaged anthropogenic emissions for the year 2006 over Europe are provided by TNO at a 0.1×0.1 degree resolution. Emission sources have been classified into different activities according to the Standard Nomenclature for Air Pollution (SNAP). The available data include annual total emissions of CH4, CO, NH3, NMVOC, NOx, PM10, PM2.5, and SO2 for both area and point sources in ten (10) SNAP categories: power generation, residential-commercial and other combustion, industrial combustion, industrial processes, extraction distribution of fossil fuels, solvent use, road transport, other mobile sources, waste treatment and disposal, agriculture. Mobile sources and road transport are the major sources of NOx emissions followed by power generation units. Power generation is also the major source for SO2 emissions followed by mobile sources. Agricultural activities dominate NH3 emissions while combustion sources followed by mobile sources and road transport are the main sources for primary PM2.5. Emissions are processed by the Sparse Matrix Operator Kernel Emissions (SMOKE) v2.6 modeling system to convert their resolution to the resolution needed by the air quality model The Community Multiscale Air Quality (CMAQ) v4.7 Modeling System with the Carbon Bond mechanism (CB05) is used for the regional air quality modeling over Europe at 35km grid spacing. Results quantify the contribution of each SNAP category on ozone and PM2.5 concentrations, locally, across Europe.

  17. 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...

  18. 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...

  19. 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...

  20. 40 CFR 52.2332 - Control Strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control Strategy: Ozone. 52.2332...: Ozone. Determinations—EPA is determining that, as of July 18, 1995, the Salt Lake and Davis Counties ozone nonattainment area has attained the ozone standard based on air quality monitoring data from...

  1. 40 CFR 52.2332 - Control Strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control Strategy: Ozone. 52.2332...: Ozone. Determinations—EPA is determining that, as of July 18, 1995, the Salt Lake and Davis Counties ozone nonattainment area has attained the ozone standard based on air quality monitoring data from...

  2. 40 CFR 52.2332 - Control Strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control Strategy: Ozone. 52.2332...: Ozone. Determinations—EPA is determining that, as of July 18, 1995, the Salt Lake and Davis Counties ozone nonattainment area has attained the ozone standard based on air quality monitoring data from...

  3. 40 CFR 52.2332 - Control Strategy: Ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control Strategy: Ozone. 52.2332...: Ozone. Determinations—EPA is determining that, as of July 18, 1995, the Salt Lake and Davis Counties ozone nonattainment area has attained the ozone standard based on air quality monitoring data from...

  4. 40 CFR 52.2235 - Control strategy: Ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Ozone. 52.2235... strategy: Ozone. (a) Determination—EPA is determining that, as of August 8, 1995, the Nashville ozone nonattainment area has attained the ozone standard and that the reasonable further progress and...

  5. TES V006 L2 Ozone Product Reprocessing Complete

    Atmospheric Science Data Center

    2015-03-18

    TES V006 L2 Ozone Product Reprocessing Complete Wednesday, February 18, 2015 An improvement in the TES Level 2 ozone species retrieval quality flag algorithm was implemented to utilize the TES water and atmospheric temperature retrievals in the ozone quality determination.  Updates to the V006 TES Level 2 ozone standard ...

  6. Microporous carbon filters as catalysts for ozone decomposition

    SciTech Connect

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

    1995-02-01

    Ozone, an allotrope of oxygen, present in the upper atmosphere (ozonosphere) plays a critical role in radiative balance. However, ozone is a toxic gas with a pungent odor when present in the troposphere and is considered a health hazard. The Occupational Safety and Health Administration (OSHA) has established a maximum permissible exposure limit (PEL) of 0.1 ppM in an 8 hour period. There are many sources of exposure to ozone in the workplace. Ozone is generated by high voltage discharge wires found in laser printers and photocopiers. Other common uses for ozone include waste water treatment, medical and dental instrument sterilization, drinking water purification, industrial oxidation processes, bleaching, and as a bactericide in swimming pools. Carbon filters are often used to minimize worker exposure to ozone. When designing a filter to decompose unwanted ozone, there are three requirements for most commercial applications. The first requirement is that production costs of the filter be minimal. Many applications require large quantities of filters and may have to be changed out often. The relatively low PEL also requires the filters to have a very high ozone decomposition efficiency. Finally, current applications tend to use small, low power fans to move air through the filters. Low back pressure is required to prevent over heating and prevent buildup of the toxic and potentially explosive ozone. In this paper, we will discuss two porous carbon filters that satisfy all of these requirements.

  7. H.R. 3505: This Act may be cited as the Revised Ozone and Particulate Matter Standards Implementation Act of 1998, introduced in the House of Representatives, One Hundred Fifth Congress, Second Session, March 19, 1998

    SciTech Connect

    1998-12-31

    The purpose of this bill is to amend the Clean Air Act to provide for the implementation of the revised ozone and particulate matter standards. Under current law, many areas may not achieve the revised standards for as long as twenty years, and some areas may take even longer. Without changes in current law, implementation of the revised standards may result in unnecessary costs and delays. One of the goals of this amendment is to attain the standards and protect public health without sacrificing economic growth.

  8. 78 FR 65559 - Approval and Promulgation of Implementation Plans; Florida; Infrastructure Requirements for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-01

    ... Requirements for the 2008 8-Hour Ozone National Ambient Air Quality Standards AGENCY: Environmental Protection... for the 2008 8-Hour Ozone 110(a)(2)(D)(i)(I National Ambient Air Quality ) concerning Standards...)(i)(II), and 110(a)(2)(J) for the 2008 8-hour Ozone National Ambient Air Quality Standards related...

  9. 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...

  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... 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...

  11. Influence of synoptic patterns on surface ozone variability over the eastern United States from 1980 to 2012

    NASA Astrophysics Data System (ADS)

    Shen, L.; Mickley, L. J.; Tai, A. P. K.

    2015-10-01

    We investigate the effect of synoptic-scale weather patterns on observed maximum daily 8-hour average (MDA8) surface ozone over the eastern United States during 1980-2012 in summer (June-August, JJA). Zonally averaged, the relative standard deviation (SD) of daily MDA8 JJA ozone shows a bimodal structure, with peaks at 28-32 and 40-45° N, and we show that those regions are most influenced by the variability in daily weather. We apply empirical orthogonal functions (EOFs) to understand the causes of this structure. The first three leading EOF patterns explain 53 % of the total variance in detrended surface ozone, displaying (1) a widespread response of ozone in the eastern United States associated with north-south movement of jet wind latitude, (2) a north-south pattern linked to the Bermuda High system when its west boundary is located along the east coast, and (3) an east-west pattern characteristic of a westward extension of the Bermuda High and an enhanced Great Plains low level jet (GPLLJ). The northern peak of ozone relative SD can be explained by polar jet activity, while the southern peak appears related to variability in the Bermuda High and GPLLJ. We define a new metric polar jet frequency as the total number of days the jet traverses the Midwest and northeast each summer. In the Midwest and northeast, we find that the correlation coefficient r between detrended mean JJA MDA8 ozone and the polar jet frequency ranges between -0.76 and -0.93 over 1980-2012 depending on the time period selected, suggesting that polar jet frequency could provide a simple metric to predict ozone variability in future climate regimes. In the southeast, the influence of the Bermuda High on mean JJA MDA8 ozone depends on the location of its west edge. For those summers when the average position of the west edge is located west of ~ 85.4° W, a westward shift in the Bermuda High west edge increases ozone in the southeast by ~ 1 ppbv deg-1 in longitude. For all summers, a northward

  12. 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.

  13. 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

  14. 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

  15. 78 FR 28550 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lake and Porter Counties...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-15

    ... Porter Counties, Indiana, 1997 8-Hour Ozone Maintenance Plan and 1997 Annual Fine Particulate Matter... and Porter State Implementation Plans (SIPs) for the 1997 8-hour ozone standard, and the 1997...

  16. A total ozone-dependent ozone profile climatology based on ozonesondes and Aura MLS data

    NASA Astrophysics Data System (ADS)

    Labow, Gordon J.; Ziemke, Jerald R.; McPeters, Richard D.; Haffner, David P.; Bhartia, Pawan K.

    2015-03-01

    Ozone profiles measured with the Aura Microwave Limb Sounder (MLS) and ozonesondes are used to create a new ozone climatology that can be used for satellite retrievals and radiative transfer studies. The climatology is binned according to total column ozone amount and latitude rather than with season. Because of high correlation between ozone profile shape and total ozone, the ozone profiles in this climatology capture ozone variations well, especially near the tropopause. This climatology has been constructed from nearly a million individual MLS ozone profile measurements taken between 2004 and 2013 as well as over 55,000 ozonesonde measurements from 1988 to 2011. The MLS profiles were sorted by total column ozone as measured by Ozone Monitoring Instrument in observations that were coincident with the MLS measurements. The data from the sondes were used in the troposphere and lower stratosphere and MLS in the middle and upper stratosphere. These two data sets were blended together between 13 and 17 km (~159-88 hPa). This climatology consists of average ozone profiles as a function of total ozone for six 30° latitude bands covering altitudes between 0 and 75 km (in Z* pressure altitude coordinates) as well as the corresponding standard deviations for each layer. There is no seasonal component. This new climatology shows some remarkable and somewhat unexpected correlations between the total column ozone and the ozone amount at some layers, particularly in the lower and middle troposphere in some latitude bands.

  17. 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

  18. Local fluctuations of ozone from 16 km to 45 km deduced from in situ vertical ozone profile

    NASA Technical Reports Server (NTRS)

    Moreau, G.; Robert, C.

    1994-01-01

    A vertical ozone profile obtained by an in situ ozone sonde from 16 km to 45 km, has allowed to observe local ozone concentration variations. These variations can be observed, thanks to a fast measurement system based on a UV absorption KrF excimer laser beam in a multipass cell. Ozone standard deviation versus altitude calculated from the mean is derived. Ozone variations or fluctuations are correlated with the different dynamic zones of the stratosphere.

  19. 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.

  20. 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.

  1. 77 FR 5210 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-02

    ... background for this action? On July 18, 1997 (62 FR 38856), EPA promulgated an 8-hour ozone standard of 0.08... 1997 8-hour ozone standard (69 FR 23951, April 30, 2004), an area was classified under subpart 2 of the..., 8-hour ozone moderate nonattainment area by EPA on April 30, 2004 (69 FR 23858, 23898, and...

  2. 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...

  3. 40 CFR 51.912 - What requirements apply for reasonably available control technology (RACT) and reasonably...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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...

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

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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...

  6. Ozone Reductions Using Residential Building Envelopes

    SciTech Connect

    Walker, Iain S.; Sherman, Max; Nazaroff, William W.

    2009-02-01

    Ozone is an air pollutant with that can have significant health effects and a significant source of ozone in some regions of California is outdoor air. Because people spend the vast majority of their time indoors, reduction in indoor levels of ozone could lead to improved health for many California residents. Ozone is removed from indoor air by surface reactions and can also be filtered by building envelopes. The magnitude of the envelope impact depends on the specific building materials that the air flows over and the geometry of the air flow paths through the envelope that can be changes by mechanical ventilation operation. The 2008 Residential Building Standards in California include minimum requirements for mechanical ventilation by referencing ASHRAE Standard 62.2. This study examines the changes in indoor ozone depending on the mechanical ventilation system selected to meet these requirements. This study used detailed simulations of ventilation in a house to examine the impacts of different ventilation systems on indoor ozone concentrations. The simulation results showed that staying indoors reduces exposure to ozone by 80percent to 90percent, that exhaust ventilation systems lead to lower indoor ozone concentrations, that opening of windows should be avoided at times of high outdoor ozone, and that changing the time at which mechanical ventilation occurs has the ability to halve exposure to ozone. Future work should focus on the products of ozone reactions in the building envelope and the fate of these products with respect to indoor exposures.

  7. Extended workdays: Effects of 8-hour and 12-hour rotating shift schedules on test performance, subjective alertness, sleep patterns, and psychological variables

    SciTech Connect

    Rosa, R.R.; Colligan, M.J.; Lewis, P.

    1986-06-01

    A newly instituted 3 to 4 day/12-hr rotating shift schedule was compared to the previous 5 to 7 day/8-hr schedule using standard laboratory-type measures of performance and alertness, and a questionnaire on sleep patterns and other personal habits. After seven months adaptation to the new schedule, a preliminary analysis indicates that there were some decrements in alertness, reductions in sleep, and disruptions of other personal activities during 12-hr workdays. Gastro-intestinal state improved during night shift, however, and increases in self-reported stress were reduced by the shortened workweek. These results are discussed in terms of trade-offs between longer workdays and shorter workweeks. It is emphasized that at this time no determination can be made of the extent of risk associated with these changes in alertness.

  8. Effects of ozone and peroxyacetyl nitrate on polar lipids and Fatty acids in leaves of morning glory and kidney bean.

    PubMed

    Nouchi, I; Toyama, S

    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. PMID:16666199

  9. 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

  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. 77 FR 56775 - Approval and Promulgation of Implementation Plans; California; Determinations of Attainment for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-14

    ...EPA is making several determinations relating to 1997 8-hour ozone nonattainment areas in California. First, EPA is determining that six 8-hour ozone nonattainment areas in California (Amador and Calaveras Counties, Chico, Kern County, Mariposa and Tuolumne Counties, Nevada County, and Sutter County) (``six CA areas'') attained the 1997 8-hour ozone national ambient air quality standard......

  13. 77 FR 25363 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-30

    ... FR 23858), EPA published a final rule designating and classifying areas under the 8-hour ozone NAAQS... data, 2001-2003. Under EPA's implementation rule for the 1997 8-hour ozone standard (69 FR 23951, April... FR 23958). The St. Louis area was classified as a subpart 2, 8-hour ozone moderate nonattainment...

  14. 77 FR 11739 - Approval and Promulgation of Air Quality Implementation Plans; District of Columbia, Maryland...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-28

    ..., Maryland, and Virginia; Determinations of Attainment of the 1997 8-Hour Ozone National Ambient Air Quality... determination that the Washington Area has attained the 1997 8-hour ozone national ambient air quality standard... Air Quality Monitoring Data Complete, quality assured, certified 8-hour ozone air quality......

  15. TROP OZONE

    EPA Science Inventory

    Activity Area (F01) The NRMRL tropospheric ozone research program is both coordinated with the research efforts of others and planned to achieve the most important unmet research needs that draw upon its unique expertise. For example, NRMRL emissions research in this area is co...

  16. Stricter clean air standards

    SciTech Connect

    Schell, D.

    1997-07-01

    New standards for ozone and particulate matter stir a debate between the EPA and industrial groups. The article discusses both the history of the ozone and particulates standards, the goal of the EPA to protect health and evaluation of what the standards mean to health, and the industrial response.

  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. Ozone and aircraft operations

    NASA Technical Reports Server (NTRS)

    Perkins, P. J.

    1981-01-01

    The cabin ozone problem is discussed. Cabin ozone in terms of health effects, the characteristics of ozone encounters by aircraft, a brief history of studies to define the problem, corrective actions taken, and possible future courses of action are examined. It is suggested that such actions include avoiding high ozone concentrations by applying ozone forecasting in flight planning procedures.

  19. Y-12 Plant Stratospheric Ozone Protection plan

    SciTech Connect

    1995-09-01

    The Y-12 Plant staff is required by Lockheed Martin Energy Systems (Energy Systems) (formerly Martin Marietta Energy Systems) standard ESS-EP-129 to develop and implement a Stratospheric Ozone Protection Program which will minimize emissions of ozone-depleting substances to the environment and maximize the use of ozone-safe alternatives in order to comply with Title VI of the 1990 Clean Air Act (CAA) Amendments and the implementing regulations promulgated by the Environmental Protection Agency (EPA). This plan describes the requirements, initiatives, and accomplishments of the Y-12 Plant Stratospheric Ozone Protection Program.

  20. 40 CFR 52.1129 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 CFR 51.918), this determination suspends the reasonable further progress and attainment... ozone standard. Under the provisions of EPA's ozone implementation rule (see 40 CFR 51.918), this... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Ozone....

  1. 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

    appear to be very promising. Addition of the new Brewer ozone data extracted from current measurements at selected US continental sites is expected to enhance global ground-based ozone data sets when used in the future trend analysis. The multi-spectral algorithm allows retrieving profiles for measurements taken at shorter SZA range (between 88 and 90 degrees) as compared to the 70-90 SA range of the standard Umkehr retrieval. It shortens operational time and allows for better data management. This addition to the well-established, but aging Dobson Umkehr network assures continuous ground-based support for current and future satellite-based global monitoring of stratospheric ozone recovery. The new dataset is expected to contribute to the understanding of the sources, transformation, and transport of trace species in the Earth's atmosphere which will be based on the continuous NOAA/SBUV, Aura/OMI, and future OMPS aboard the JPSS (former NPOESS) Earth observations from space.

  2. 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

  3. 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)

  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. High Resolution Space-Time Ozone Modeling for Assessing Trends

    PubMed Central

    Sahu, Sujit K.; Gelfand, Alan E.; Holland, David M.

    2008-01-01

    The assessment of air pollution regulatory programs designed to improve ground level ozone concentrations is a topic of considerable interest to environmental managers. To aid this assessment, it is necessary to model the space-time behavior of ozone for predicting summaries of ozone across spatial domains of interest and for the detection of long-term trends at monitoring sites. These trends, adjusted for the effects of meteorological variables, are needed for determining the effectiveness of pollution control programs in terms of their magnitude and uncertainties across space. This paper proposes a space-time model for daily 8-hour maximum ozone levels to provide input to regulatory activities: detection, evaluation, and analysis of spatial patterns of ozone summaries and temporal trends. The model is applied to analyzing data from the state of Ohio which has been chosen because it contains a mix of urban, suburban, and rural ozone monitoring sites in several large cities separated by large rural areas. The proposed space-time model is auto-regressive and incorporates the most important meteorological variables observed at a collection of ozone monitoring sites as well as at several weather stations where ozone levels have not been observed. This problem of misalignment of ozone and meteorological data is overcome by spatial modeling of the latter. In so doing we adopt an approach based on the successive daily increments in meteorological variables. With regard to modeling, the increment (or change-in-meteorology) process proves more attractive than working directly with the meteorology process, without sacrificing any desired inference. The full model is specified within a Bayesian framework and is fitted using MCMC techniques. Hence, full inference with regard to model unknowns is available as well as for predictions in time and space, evaluation of annual summaries and assessment of trends. PMID:19759840

  6. Sensitivity Modeling Study for an Ozone Occurrence during the 1996 Paso Del Norte Ozone Campaign

    PubMed Central

    Lu, Duanjun; Reddy, Remata S.; Fitzgerald, Rosa; Stockwell, William R.; Williams, Quinton L.; Tchounwou, Paul B.

    2008-01-01

    Surface ozone pollution has been a persistent environmental problem in the US and Europe as well as the developing countries. A key prerequisite to find effective alternatives to meeting an ozone air quality standard is to understand the importance of local anthropogenic emissions, the significance of biogenic emissions, and the contribution of long-range transport. In this study, an air quality modeling system that includes chemistry and transport, CMAQ, an emission processing model, SMOKE, and a mesoscale numerical meteorological model, WRF, has been applied to investigate an ozone event occurring during the period of the 1996 Paso del Norte Ozone Campaign. The results show that the modeling system exhibits the capability to simulate this high ozone occurrence by providing a comparable temporal variation of surface ozone concentration at one station and to capture the spatial evolution of the event. Several sensitivity tests were also conducted to identify the contributions to high surface ozone concentration from eight VOC subspecies, biogenic VOCs, anthropogenic VOCs and long-range transportation of ozone and its precursors. It is found that the reductions of ETH, ISOP, PAR, OLE and FORM help to mitigate the surface ozone concentration, and like anthropogenic VOCs, biogenic VOC plays a nonnegligible role in ozone formation. But for this case, long-range transport of ozone and its precursors appears to produce an insignificant contribution. PMID:19190351

  7. 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.

  8. Long-term ozone monitoring from space

    NASA Astrophysics Data System (ADS)

    Ahmad, S.; Johnson, J.; Serafino, G.; McPeters, R.

    Global monitoring of ozone is important since ozone shields the biosphere from the harmful effects of solar radiation by absorbing the ultraviolet radiation below 320 nanometers (UV-B wavelength regions). By absorbing UV, visible, and infrared radiation, ozone also heats the stratosphere and affects the circulation of air masses and dynamics of the upper atmosphere. Ozone also plays an important role in the chemical cycles of the other trace gases. In the last two decades a number of sensors have been flown on satellites to monitor ozone from space. Daily global ozone maps of total column ozone were obtained from the Total Ozone Mapping Spectrometer (TOMS) instruments flown on the Nimbus-7, Meteor-3, Advanced Earth Observing Satellite (ADEOS) and Earth Probe (EP) satellites, and from the Global Ozone Monitoring experiment (GOME) onboard the second European Remote Sensing Satellite (ERS-2). The high quality measurements of the first TOMS instrument (flown on Nimbus-7 in 1978) played an instrumental role in the detection of a small but steady ozone decline since the early 1980s. This has led to investigation of the cause of ozone depletion in an effort to quantify how much of this could be attributed to human made processes as opposed to natural processes. The significance of this issue was underscored by the signing of the Montreal Protocol in 1987 restricting the production of ozone destroying chemicals. Furthermore, in September 1991, the Upper Atmosphere Research Satellite (UARS) was launched containing a comprehensive suite of instruments designed to collectively determine the impact of chemical, dynamic and energy input processes on ozone creation and destruction. The continuity of ozone, other trace species, and solar UV measurements will be provided with the launch of the Aura spacecraft in early 2004. Standard ozone products from a series of TOMS missions, UARS sensors, Nimbus-4 Backscatter Ultraviolet Spectrometer (BUV), and Nimbus-7 Solar Backscatter

  9. Long-term Ozone monitoring from space

    NASA Astrophysics Data System (ADS)

    Ahmad, S.; Johnson, J.; Serafino, G.; McPeters, R.

    Global monitoring of ozone is important since ozone shields the biosphere from the harmful effects of solar radiation by absorbing the ultraviolet radiation below 320 nanometers (UV-B wavelength regions). By absorbing UV, visible, and infrared radiation, ozone also heats the stratosphere and affects the circulation of air masses and dynamics of the upper atmosphere. Ozone also plays an important role in the chemical cycles of the other trace gases. In the last two decades a number of sensors have been flown on satellites to monitor ozone from space. Daily global ozone maps of total column ozone were obtained from the Total Ozone Mapping Spectrometer (TOMS) instruments flown on the Nimbus-7, Meteor-3, Advanced Earth Observing Satellite (ADEOS) and Earth Probe (EP) satellites, and from the Global Ozone Monitoring experiment (GOME) onboard the second European Remote Sensing Satellite (ERS-2). The high quality measurements of the first TOMS instrument (flown on Nimbus-7 in 1978) played an instrumental role in the detection of a small but steady ozone decline since the early 1980s. This has led to investigation of the cause of ozone depletion in an effort to quantify how much of this could be attributed to human made processes as opposed to natural processes. The significance of this issue was underscored by the signing of the Montreal Protocol in 1987 restricting the production of ozone destroying chemicals. Furthermore, in September 1991, the Upper Atmosphere Research Satellite (UARS) was launched containing a comprehensive suite of instruments designed to collectively determine the impact of chemical, dynamic and energy input processes on ozone creation and destruction. The continuity of ozone, other trace species, and solar UV measurements will be provided with the launch of the Aura spacecraft in early 2004. Standard ozone products from a series of TOMS missions, UARS sensors, Nimbus-4 Backscatter Ultraviolet Spectrometer (BUV), and Nimbus-7 Solar Backscatter

  10. 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...

  11. 78 FR 17902 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-25

    ... December 28, 2012. \\1\\ On March 27, 2008 (73 FR 16436), EPA promulgated a revised 8-hour ozone standard of... nonattainment for the 2008 8-hour ozone standard (77 FR 30088). This rulemaking relates only to the 1997 8-hour... Basin as a nonattainment area (SDAB nonattainment area) for the photochemical oxidant NAAQS. See 43...

  12. 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.

  13. Impact of enhanced ozone deposition and halogen chemistry on tropospheric ozone over the Northern Hemisphere

    EPA Science Inventory

    Fate of ozone in marine environments has been receiving increased attention due to the tightening of ambient air quality standards. The role of deposition and halogen chemistry is examined through incorporation of an enhanced ozone deposition algorithm and inclusion of halogen ch...

  14. Estimation of ozone with total ozone portable spectroradiometer instruments. II. Practical operation and comparisons

    NASA Astrophysics Data System (ADS)

    Labow, Gordon J.; Flynn, Lawrence E.; Rawlins, Michael A.; Beach, Robert A.; Simmons, C. A.; Schubert, C. M.

    1996-10-01

    We used a microcomputer-controlled total ozone portable spectroradiometer instrument 21 (MTOPS21) to measure solar radiation at 298, 304 and 310 nm in Greenbelt, Md., during 1995. One day s ozone measurements from a Brewer instrument (B105) were used to calibrate the 304- and 310-nm channel ratios to a theoretical model. Total ozone estimates were then determined for the entire MTOPS21 data set. Differences between individual B105 and MTOPS21 ozone estimates show a 1 drop as solar zenith angles increase and depend on atmospheric attenuation and SO 2 variation at the 2 level. Daily average values agree well ( 0.5 average offset, 2 standard deviation).

  15. The 1988 Antarctic ozone depletion: Comparison with previous year depletions

    SciTech Connect

    Schoeberl, M.R.; Stolarski, R.S.; Krueger, A.J. )

    1989-05-01

    The 1988 spring Antarctic ozone depletion was observed by TOMS to be substantially smaller than in recent years. The minimum polar total ozone values declined only 15% during September 1988 compared to nearly 50% during September 1987. At southern midlatitudes, exceptionally high total ozone values were recorded beginning in July 1988. The total integrated southern hemispheric ozone increased rapidly during the Austral spring, approaching 1980 levels during October. The high midlatitude total ozone values were associated with a substantial increase in eddy activity as indicated by the standard deviation in total ozone in the zonal band 30{degree}-60{degree}S. The standard deviation also correlates with the QBO cycling of the tropical winds. Mechanisms through which the increased midlatitude eddy activity could disrupt the formation of the Antarctic ozone hole are briefly discussed.

  16. 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

  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. 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

  19. Ambient ozone causes upper airways inflammation in children

    SciTech Connect

    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. 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.

  2. Impact of Enhanced Ozone Deposition and Halogen Chemistry on Tropospheric Ozone over the Northern Hemisphere.

    PubMed

    Sarwar, Golam; Gantt, Brett; Schwede, Donna; Foley, Kristen; Mathur, Rohit; Saiz-Lopez, Alfonso

    2015-08-01

    Fate of ozone in marine environments has been receiving increased attention due to the tightening of ambient air quality standards. The role of deposition and halogen chemistry is examined through incorporation of an enhanced ozone deposition algorithm and inclusion of halogen chemistry in a comprehensive atmospheric modeling system. The enhanced ozone deposition treatment accounts for the interaction of iodide in seawater with ozone and increases deposition velocities by 1 order of magnitude. Halogen chemistry includes detailed chemical reactions of organic and inorganic bromine and iodine species. Two different simulations are completed with the halogen chemistry: without and with photochemical reactions of higher iodine oxides. Enhanced deposition reduces mean summer-time surface ozone by ∼3% over marine regions in the Northern Hemisphere. Halogen chemistry without the photochemical reactions of higher iodine oxides reduces surface ozone by ∼15% whereas simulations with the photochemical reactions of higher iodine oxides indicate ozone reductions of ∼48%. The model without these processes overpredicts ozone compared to observations whereas the inclusion of these processes improves predictions. The inclusion of photochemical reactions for higher iodine oxides leads to ozone predictions that are lower than observations, underscoring the need for further refinement of the halogen emissions and chemistry scheme in the model. PMID:26151227

  3. Children's and adults' knowledge and models of reasoning about the ozone layer and its depletion

    NASA Astrophysics Data System (ADS)

    Leighton, Jacqueline P.; Bisanz, Gay L.

    2003-01-01

    As environmental concepts, the ozone layer and ozone hole are important to understand because they can profoundly influence our health. In this paper, we examined: (a) children's and adults' knowledge of the ozone layer and its depletion, and whether this knowledge increases with age' and (b) how the 'ozone layer' and 'ozone hole' might be structured as scientific concepts. We generated a standardized set of questions and used it to interview 24 kindergarten students, 48 Grade 3 students, 24 Grade 5 students, and 24 adults in university, in Canada. An analysis of participants' responses revealed that adults have more knowledge than children about the ozone layer and ozone hole, but both adults and children exhibit little knowledge about protecting themselves from the ozone hole. Moreover, only some participants exhibited 'mental models' in their conceptual understanding of the ozone layer and ozone hole. The implications of these results for health professionals, educators, and scientists are discussed.

  4. The 1988 Antarctic ozone depletion - Comparison with previous year depletions

    NASA Technical Reports Server (NTRS)

    Schoeberl, Mark R.; Stolarski, Richard S.; Krueger, Arlin J.

    1989-01-01

    The 1988 spring Antarctic ozone depletion was observed by TOMS to be substantially smaller than in recent years. The minimum polar total ozone values declined only 15 percent during September 1988, compared to nearly 50 percent during September 1987. At southern midlatitudes, exceptionally high total ozone values were recorded beginning in July 1988. The total integrated southern hemispheric ozone increased rapidly during the Austral spring, approaching 1980 levels during October. The high midlatitude total ozone values were associated with a substantial increase in eddy activity as indicated by the standard deviation in total ozone in the zonal band 30-60 deg S. Mechanisms through which the increased midlatitude eddy activity could disrupt the formation of the Antarctic ozone hole are briefly discussed.

  5. 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.

  6. Tropospheric Ozone and Photochemical Smog

    NASA Astrophysics Data System (ADS)

    Sillman, S.

    2003-12-01

    emitted species, in a process that is driven by sunlight and is accelerated by warm temperatures. This smog is largely the product of gasoline-powered engines (especially automobiles), although coal-fired industry can also generate photochemical smog. The process of photochemical smog formation was first identified by Haagen-Smit and Fox (1954) in association with Los Angeles, a city whose geography makes it particularly susceptible to this type of smog formation. Sulfate aerosols and organic particulates are often produced concurrently with ozone, giving rise to a characteristic milky-white haze associated with this type of air pollution.Today ozone and particulates are recognized as the air pollutants that are most likely to affect human health adversely. In the United States, most major metropolitan areas have periodic air pollution events with ozone in excess of government health standards. Violations of local health standards also occur in major cities in Canada and in much of Europe. Other cities around the world (especially Mexico City) also experience very high ozone levels. In addition to urban-scale events, elevated ozone occurs in region-wide events in the eastern USA and in Western Europe, with excess ozone extending over areas of 1,000 km2 or more. Ozone plumes of similar extent are found in the tropics (especially in Central Africa) at times of high biomass burning (e.g., Jenkins et al., 1997; Chatfield et al., 1998). In some cases ozone associated with biomass burning has been identified at distances up to 104 km from its sources (Schultz et al., 1999).Ozone also has a significant impact on the global troposphere, and ozone chemistry is a major component of global tropospheric chemistry. Global background ozone concentrations are much lower than urban or regional concentrations during pollution events, but there is evidence that the global background has increased as a result of human activities (e.g., Wang and Jacob, 1998; Volz and Kley, 1988). A rise in

  7. Ozone in the free atmosphere

    NASA Technical Reports Server (NTRS)

    Whitten, R. C. (Editor); Prasad, S. S. (Editor)

    1985-01-01

    The present book provides a summary of the state of scientific knowledge of stratospheric and free tropospheric ozone as it exists at the beginning of 1983. Ozone photochemistry in the stratosphere is discussed, taking into account fundamental molecular properties, the absorption spectrum of ozone, photodissociation, ozone formation and destruction in the upper atmosphere, the photochemistry of odd-hydrogen, the photochemistry of odd-nitrogen, the photochemistry of odd-chlorine, and photochemistry-temperature coupling. The observed distribution of atmospheric ozone and its variations are considered along with ozone transport, ozone in the troposphere, stratospheric ozone perturbations, and climatic and biological effects. Attention is given to the techniques of observing atmospheric ozone, horizontal-vertical ozone transport and conservative quantities, measurements of tropospheric ozone, the tropospheric ozone budget, ozone models, natural ozone variations, and anthropogenic ozone perturbations.

  8. 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.

  9. 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.

  10. 2001 OZONE DESIGN VALUE

    EPA Science Inventory

    Ozone is generated by a complex atmoshperic chemical process. Industrial and automobile pollutants in the form of oxides of nitrogen and hydrocarbons react in the atmosphere when air is stagnant and temperatures are high to form ozone. Ozone is known to cause adverse health eff...

  11. 2020 OZONE DESIGN VALUE

    EPA Science Inventory

    Ozone is generated by a complex atmoshperic chemical process. Industrial and automobile pollutants in the form of oxides of nitrogen and hydrocarbons react in the atmosphere when air is stagnant and temperatures are high to form ozone. Ozone is known to cause adverse health eff...

  12. OZONE BYPRODUCT FORMATION

    EPA Science Inventory

    The use of ozone for water treatment has been increasing as ozone has great potential for degrading water pollutants and inactivating viruses, Giardia cysts, and Cryptosporidium oocysts. Although it appears that ozone generates less undesirable disinfection by-products (DBPs) th...

  13. 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...

  14. Airliner cabin ozone: An updated review. Final report

    SciTech Connect

    Melton, C.E.

    1989-12-01

    The recent literature pertaining to ozone contamination of airliner cabins is reviewed. Measurements in airliner cabins without filters showed that ozone levels were about 50 percent of atmospheric ozone. Filters were about 90 percent effective in destroying ozone. Ozone (0.12 to 0.14 ppmv) caused mild subjective respiratory irritation in exercising men, but 0.20 to 0.30 ppmv did not have adverse effects on patients with chronic heart or lung disease. Ozone (1.0 to 2.0 ppmv) decreased survival time of influenza-infected rats and mice and suppressed the capacity of lung macrophages to destroy Listeria. Airway responses to ozone are divided into an early parasympathetically mediated bronchoconstrictive phase and a later histamine-mediated congestive phase. Evidence indicates that intracellular free radicals are responsible for ozone damage and that the damage may be spread to other cells by toxic intermediate products: Antioxidants provide some protection to cells in vitro from ozone but dietary intake of antioxidant vitamins by humans has only a weak effect, if any. This review indicates that earlier findings regarding ozone toxicity do not need to be corrected. Compliance with existing FAA ozone standards appears to provide adequate protection to aircrews and passengers.

  15. 78 FR 29306 - Approval and Promulgation of Implementation Plans; Florida; Infrastructure Requirements for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-20

    ... Requirements for the 2008 8-Hour Ozone National Ambient Air Quality Standards AGENCY: Environmental Protection... Implement the 8-Hour Ozone National Ambient Air Quality Standard--Phase 2; Final Rule'' (November 29, 2005... of ozone and other pollutant forecasting, including an air quality monitoring Web site...

  16. The origin of ozone

    NASA Astrophysics Data System (ADS)

    Grewe, V.

    2006-05-01

    Highest atmospheric ozone production rates can be found at around 30 km in the tropical stratosphere, leading to ozone mixing ratios of about 10 ppmv. Those stratospheric air masses are then transported to extra-tropical latitudes via the Brewer-Dobson circulation. This is considered the main mechanism to generate mid- and high latitude ozone. By applying the climate-chemistry models E39/C and MAECHAM4/CHEM, this view is investigated in more detail. The origin of ozone in the troposphere and stratosphere is analysed, by incorporating a diagnostics ("marked ozone origin tracers") into the models, which allows to identify the origin of ozone. In most regions the simulated local ozone concentration is dominated by local ozone production, i.e. less than 50% of the ozone at higher latitudes of the stratosphere is produced in the tropics, which conflicts with the idea that the tropics are the global source for stratospheric ozone. Although episodic stratospheric intrusions occur basically everywhere, the main ozone stratosphere-to-troposphere exchange is connected to exchange processes at the sub-tropical jet-stream. The simulated tropospheric influx of ozone amounts to 420 Tg per year, and originates in the Northern Hemisphere from the extra-tropical stratosphere, whereas in the Southern Hemisphere a re-circulation of tropical tropospheric ozone contributes most to the influx of ozone into the troposphere. In the model E39/C, the upper troposphere of both hemispheres is clearly dominated by tropical tropospheric ozone (40%-50%) except for northern summer hemisphere, where the tropospheric contribution (from the tropics as well as from the Northern Hemisphere) does not exceed 20%.

  17. 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

  18. High concentration of surface ozone observed along the Khumbu Valley Nepal April 2007

    NASA Astrophysics Data System (ADS)

    Moore, G. W. K.; Semple, J. L.

    2009-07-01

    Increasing air pollution in Southeast Asia has the potential for dramatic impacts on the population and climate in relatively pristine regions such as the Himalaya. Recent measurements near Mount Everest indicate the presence of elevated levels of ozone at elevations from 5000m to 9000m that are the result of both the long-range transport of tropospheric pollutants from Southeast Asia as well as the descent of ozone-rich stratospheric air. Here we report on the first surface ozone concentration transect in the Mount Everest region. The data collected at elevations from 2900m to 5200m indicate an increase in concentration with height as well as 8-hour average exposures in excess of 140ppb. Satellite data and meteorological diagnostics suggest a stratospheric source for the high levels observed. The majority of values observed exceed guidelines for human exposure and therefore are of a magnitude to suggest that they are of physiological relevance.

  19. Using Ozone Lidar to Investigate Sources of High Ozone Concentrations in the Western United States

    NASA Astrophysics Data System (ADS)

    Senff, C. J.; Langford, A. O.; Alvarez, R. J.; Brewer, Wm. A.; Banta, R. M.; Marchbanks, R. D.; Sandberg, S. P.; Weickmann, A. M.; Holloway, J. S.; Williams, E. J.

    2016-06-01

    We have used NOAA's Tunable Optical Profiler for Aerosol and oZone (TOPAZ) ozone lidar to investigate the sources of high surface ozone concentrations in two different regions of the western United States (US): the Uintah Basin in northeast Utah and Clark County in southern Nevada, which includes the city of Las Vegas. The Uintah Basin is a booming oil and gas producing region that often suffers from very high wintertime ozone concentrations. Clark County experiences violations of the US ozone standard primarily in spring and early summer despite a lack of any major local pollution sources. TOPAZ lidar observations, in conjunction with surface in situ measurements and model results, provided strong evidence that the high wintertime ozone concentrations in the Uintah Basin are primarily driven by local emissions associated with oil and gas exploration, whereas the Clark County ozone exceedances are often caused by ozone-rich air that is transported from the lower stratosphere all the way down to the earth's surface.

  20. Overview of ozone bleaching

    SciTech Connect

    Sonnenberg, L.B.

    1995-12-31

    The potential impact of the pulp and paper industry on the environment may be reduced by replacing chlorine-based bleaching reagents with ozone. The reactivity of ozone coupled with the heterogeneity of pulp allows many types of reactions to occur during pulp bleaching. Ozone cleaves the aromatic rings and side chain double bonds in lignin in Criegee-type mechanisms. Activated carbon-hydrogen bonds are fragmented in lignin side chains, as well as Cl carbons of {beta}-glycosides, by way of a 1,3 dipolar insertion forming a hydrotrioxide intermediate. Ozone also attacks carbohydrates at acetal oxygens, depolymerizing at the glycosidic bond. Unsaturated sites are ozonated before aliphatic sites resulting in a predominance of lignin reactions over carbohydrate reactions until lignin is substantially removed from the pulp. Important factors in the successful application of ozone bleaching include minimizing ozone decomposition and other secondary reactions, reducing exposure of cellulose to high concentrations of ozone and radicals, and promoting uniform exposure of ozone to lignin. The quantity of chlorinated organic compounds in effluents can be drastically reduced by replacing chlorine-based bleaching reagents with ozone; less organochlorine is formed and there can be greater recycle of bleach plant wastes back to the recovery cycle. Recycling of bleach plant waste also reduces total organic loading in the effluent. The toxicity of ozone filtrates is variable compared to conventional filtrates and depends on several parameters including bleaching conditions, biological treatment, and target organisms.

  1. 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

    New products from the TOMS (Total Ozone Mapping Spectrometer) >satellite instrument can resolve pollution events in tropical and mid-latitudes, Over the past several years, we have developed tropospheric ozone data sets by two methods. The modified-residual technique [Hudson and Thompson, 1998; Thompson and Hudson, 1999] uses v. 7 TOMS total ozone and is applicable to tropical regimes in which the wave-one pattern in total ozone is observed. The TOMSdirect method [Hudson et at., 2000] represents a new algorithm that uses TOMS radiances to extract tropospheric ozone in regions of constant stratospheric ozone and tropospheric ozone displaying high mixing ratios and variability characteristic of pollution, Absorbing aerosols (dust and smoke; Herman et at., 1997 Hsu et al., 1999), a standard TOMS product, provide transport and/or source marker information to interpret tropospheric ozone. For the Nimbus 7/TOMS observing period (1979-1992), modified-residual TTO (tropical tropospheric ozone) appears as two maps/month at I-degree latitude 2-degree longitude resolution at a homepage and digital data are available (20S to 20N) by ftp at http://metosrv2. umd.edu/tropo/ 14y_data.d. Preliminary modified-residual TTO data from the operational Earth-Probe/TOMS (1996- present) are posted in near-real-time at the same website. Analyses with the new tropospheric ozone and aerosol data are illustrated by the following (I)Signals in tropical tropospheric ozone column and smoke amount during ENSO (El Nino-Southern Oscillation) events, e.g. 1982-1983 and the intense ENSO induced biomass fires of 1997-1998 over the Indonesian region [Thompson et a[, 2000a, Thompson and Hudson, 1999]. (2) Trends in tropospheric ozone and smoke aerosols in various tropical regions (Atlantic, Pacific, Africa, Brazil). No significant trends were found for ozone from1980-1990 [Thompson and Hudson, 19991 although smoke aerosols increased during the period [Hsu et al.,1999]. (3) Temporal and spatial offsets

  2. 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.

  3. Spring polar ozone behavior

    NASA Technical Reports Server (NTRS)

    Aikin, Arthur C.

    1992-01-01

    Understanding of the springtime behavior of polar stratospheric ozone as of mid 1990 is summarized. Heterogeneous reactions on polar stratospheric clouds as hypothesis for ozone loss are considered and a simplified description of the behavior of Antarctic ozone in winter and spring is given. Evidence that the situation is more complicated than described by the theory is produced. Many unresolved scientific issues remain and some of the most important problems are identified. Ozone changes each spring since 1979 have clearly established for the first time that man made chlorine compounds influence stratospheric ozone. Long before important advances in satellite and in situ investigations, it was Dobson's decision to place a total ozone measuring spectrometer at Halley Bay in Antarctica during the International Geophysical Year and subsequent continuous monitoring which led to the discovery that ozone was being destroyed each spring by chlorine processed by polar stratospheric clouds.

  4. Rocket Ozone Data Recovery for Digital Archival

    NASA Astrophysics Data System (ADS)

    Hwang, S. H.; Krueger, A. J.; Hilsenrath, E.; Haffner, D. P.; Bhartia, P. K.

    2014-12-01

    Ozone distributions in the photochemically-controlled upper stratosphere and mesosphere were first measured using spectrometers on V-2 rockets after WWII. The IGY(1957-1958) spurred development of new optical and chemical instruments for flight on meteorological and sounding rockets. In the early 1960's, the US Navy developed an Arcas rocket-borne optical ozonesonde and NASA GSFC developed chemiluminescent ozonesonde onboard Nike_Cajun and Arcas rocket. The Navy optical ozone program was moved in 1969 to GSFC where rocket ozone research was expanded and continued until 1994 using Super Loki-Dart rocket at 11 sites in the range of 0-65N and 35W-160W. Over 300 optical ozone soundings and 40 chemiluminescent soundings were made. The data have been used to produce the US Standard Ozone Atmosphere, determine seasonal and diurnal variations, and validate early photochemical models. The current effort includes soundings conducted by Australia, Japan, and Korea using optical techniques. New satellite ozone sounding techniques were initially calibrated and later validated using the rocket ozone data. As satellite techniques superseded the rocket methods, the sponsoring agencies lost interest in the data and many of those records have been discarded. The current task intends to recover as much of the data as possible from the private records of the experimenters and their publications, and to archive those records in the WOUDC (World Ozone and Ultraviolet Data Centre). The original data records are handwritten tabulations, computer printouts that are scanned with OCR techniques, and plots digitized from publications. This newly recovered digital rocket ozone profile data from 1965 to 2002 could make significant contributions to the Earth science community in atmospheric research including long-term trend analysis.

  5. 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.

  6. Ozone trends: A review

    NASA Astrophysics Data System (ADS)

    Staehelin, J.; Harris, N. R. P.; Appenzeller, C.; Eberhard, J.

    2001-05-01

    Ozone plays a very important role in our atmosphere because it protects any living organisms at the Earth's surface against the harmful solar UVB and UVC radiation. In the stratosphere, ozone plays a critical role in the energy budget because it absorbs both solar UV and terrestrial IR radiation. Further, ozone in the tropopause acts as a strong greenhouse gas, and increasing ozone trends at these altitudes contribute to climate change. This review contains a short description of the various techniques that provided atmospheric ozone measurements valuable for long-term trend analysis. The anthropogenic emissions of substances that deplete ozone (chlorine- and bromine-containing volatile gases) have increased from the 1950s until the second half of the 1980s. The most severe consequence of the anthropogenic release of ozone-depleting substances is the "Antarctic ozone hole." Long-term observations indicate that stratospheric ozone depletion in the southern winter-spring season over Antarctica started in the late 1970s, leading to a strong decrease in October total ozone means. Present values are only approximately half of those observed prior to 1970. In the Arctic, large ozone depletion was observed in winter and spring in some recent years. Satellite and ground-based measurements show no significant trends in the tropics but significant long-term decreasing trends in the northern and southern midlatitudes (of the order of 2-4% per decade in the period from 1970 to 1996 and an acceleration in trends in the 1980s). Ozone at northern midlatitudes decreased by -7.4±2% per decade at 40 km above mean sea level, while ozone loss was small at 30 km. Large trends were found in the lower stratosphere, -5.1±1.8% at 20 km and -7.3±4.6% at 15 km, where the bulk of the ozone resides. The possibility of a reduction in the observed trends has been discussed recently, but it is very hard to distinguish this from the natural variability. As a consequence of the Montreal Protocol

  7. 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...

  8. Children's and Adults' Knowledge and Models of Reasoning about the Ozone Layer and Its Depletion.

    ERIC Educational Resources Information Center

    Leighton, Jacqueline P.; Bisanz, Gay L.

    2003-01-01

    Examines children's and adults' knowledge of the ozone layer and its depletion, whether this knowledge increases with age, and how the ozone layer and ozone hole might be structured as scientific concepts. Uses a standardized set of questions to interview children and adults in Canada. Discusses implications of the results for health…

  9. Oxidation of polynuclear aromatic hydrocarbons in water. 1: Ozonation

    SciTech Connect

    Beltran, F.J.; Encinar, J.M.; Rivas, J.; Ovejero, G.

    1995-05-01

    The oxidation of three polynuclear aromatic hydrocarbons (PAHs), fluorene, phenanthrene, and acenaphthene, in aqueous solution with ozone has been studied. The influence of hydroxyl radical inhibitors, pH, ozone partial pressure, and temperature was investigated. All the PAHs studied show high oxidation rates with ozone. The ozonation of fluorene seems to be due to both direct and hydroxyl radical reactions while for the rest of the PAHs the ozonation develops only through direct reactions with ozone. Rate constants for the direct reaction between these PAHs and ozone have also been calculated. The reactivity with ozone goes in the following order: fluorene < phenanthrene < acenaphthene. The contribution of radical reactions represents more than 90% in the ozonation of fluorene in most cases except in the presence of hydroxyl radical inhibitors. In a standard agitated reactor the kinetic regime of the absorption of ozone corresponds to a slow reaction in the case of fluorene and phenanthrene and to a fast reaction in the case of acenaphthene.

  10. HYDROXYL RADICAL/OZONE RATIOS DURING OZONATION PROCESSES. II. THE EFFECT OF TEMPERATURE, PH, ALKALINITY, AND DOM PROPERTIES

    EPA Science Inventory

    The influence of temperature, pH, alkalinity, and type and concentration of the dissolved organic matter (DOM) on the rate of ozone (O3) decomposition, O3-exposure, .OH-exposure and the ratio Rct of the concentrations of .OH and O3 has been studied. For a standardized single ozon...

  11. 77 FR 46755 - Notification of a Public Meeting of the Clean Air Scientific Advisory Committee (CASAC) Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-06

    ... 2012 and Policy Assessment for the Review of the Ozone National Ambient Air Quality Standards--First... appropriate, the air quality criteria and the NAAQS for the six ``criteria'' air pollutants, including ozone... Ozone National Ambient Air Quality Standards--First External Review Draft (August 2012) should...

  12. 40 CFR 96.306 - Standard requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... NOX Ozone Season Trading Program General Provisions § 96.306 Standard requirements. (a) Permit requirements. (1) The CAIR designated representative of each CAIR NOX Ozone Season source required to have a title V operating permit and each CAIR NOX Ozone Season unit required to have a title V operating...

  13. 40 CFR 96.306 - Standard requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... NOX Ozone Season Trading Program General Provisions § 96.306 Standard requirements. (a) Permit requirements. (1) The CAIR designated representative of each CAIR NOX Ozone Season source required to have a title V operating permit and each CAIR NOX Ozone Season unit required to have a title V operating...

  14. 40 CFR 96.306 - Standard requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... NOX Ozone Season Trading Program General Provisions § 96.306 Standard requirements. (a) Permit requirements. (1) The CAIR designated representative of each CAIR NOX Ozone Season source required to have a title V operating permit and each CAIR NOX Ozone Season unit required to have a title V operating...

  15. 40 CFR 96.306 - Standard requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... NOX Ozone Season Trading Program General Provisions § 96.306 Standard requirements. (a) Permit requirements. (1) The CAIR designated representative of each CAIR NOX Ozone Season source required to have a title V operating permit and each CAIR NOX Ozone Season unit required to have a title V operating...

  16. 40 CFR 96.306 - Standard requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... NOX Ozone Season Trading Program General Provisions § 96.306 Standard requirements. (a) Permit requirements. (1) The CAIR designated representative of each CAIR NOX Ozone Season source required to have a title V operating permit and each CAIR NOX Ozone Season unit required to have a title V operating...

  17. Rebound of Antarctic ozone

    NASA Astrophysics Data System (ADS)

    Salby, Murry; Titova, Evgenia; Deschamps, Lilia

    2011-05-01

    Restrictions on CFCs have led to a gradual decline of Equivalent Effective Stratospheric Chlorine (EESC). A rebound of Antarctic ozone, however, has remained elusive, masked by large interannual changes that dominate its current evolution. A positive response of ozone is not expected to emerge for at least 1-2 decades, possibly not for half a century. We show that interannual changes of the Antarctic ozone hole are accounted for almost perfectly by changes in dynamical forcing of the stratosphere. The close relationship enables dynamically-induced changes of ozone to be removed, unmasking the climate signal associated with CFCs. The component independent of dynamically-induced changes exhibits a clear upward trend over the last decade - the first signature of a rebound in Antarctic ozone. It enables ozone to be tracked relative to CFCs and other changes of climate.

  18. 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

  19. The ozone layer is recovering in mid-latitudes?

    NASA Astrophysics Data System (ADS)

    Casiccia, Claudio; Zamorano, Felix; Viana, Roberta; Paes Lema, Neusa; Quel, Eduardo; Wolfram, Elian

    2010-05-01

    During the recent decades there has been an increasing concern related to ozone layer and solar ultraviolet radiation, UV-B (280-320 nm), reaching the surface of the earth. The Antarctic Ozone Hole (AOH) is a phenomenon of strong ozone depletion in the Antarctic stratosphere, this is a consequence of heterogeneous chemical reactions and dynamical processes which enhance ozone losses by reactions with chlorine. Punta Arenas (53.0S,70.9W) is the southernmost city in Chile with a population of approximately 120000. Due to its location, well within the area affected by the Antarctic Ozone Hole. Systematic observation of ozone and UV-B with a Brewer spectrophotometer have been made in order study during the ozone hole conditions. In addition, the vertical distribution using ozosonde has been investigated during campaigns in spring time and in 2009 started regularly ECC-ozonesonde measurements, also since 2002 measurements of the ozone vertical distribution using Umkehr technique have been carry out. Intercomparisons with different ozone measurement platforms were presented. Particularly we compared a DIAL ozone vertical profile in Rio Gallegos (Argentina) with an ozonesonde measurement launched in Punta Arenas. The results were in good agreement over the 16-32 km altitude range. Also, here we present measurements of column ozone, vertical distribution of ozone and ultraviolet radiation UV-B made in Punta Arenas and Magallanes region to period 1992-2009. To analyze the behavior of the stratospheric ozone layer over Magallanes was used the reference AVE-CLI-TOMS minus twice the standard deviation of the reference mean (TOMS;1978-1987, mean monthly - 2SD). The number of days per year shows an interesting cycle of 8 to 10 years, but monthly variations did not show a significant decrease, especially during September-October period.

  20. Ozone flow visualization techniques

    NASA Technical Reports Server (NTRS)

    Dickerson, R. R.; Stedman, D. H.

    1981-01-01

    Flow visualization techniques using ozone for tracing gas flows are proposed whereby ozone is detected through its strong absorption of ultraviolet light, which is easily made visible with fluorescent materials, or through its reaction with nitric oxide to form excited nitrogen dioxide, which in relaxing emits detectable light. It is shown that response speeds in the kHz range are possible with an ultraviolet detection system for initial ozone concentrations of about 1%.

  1. 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.

  2. 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...

  3. 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

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

  4. 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

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

  5. 76 FR 17343 - Approval and Promulgation of Implementation Plans; Nevada; Determination of Attainment for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-29

    ... nonattainment area has attained the 1997 8-hour ozone national ambient air quality standards (NAAQS). This... Ozone Nonattainment Area B. Determination of Attainment C. Ambient Air Quality Monitoring Data III. What... monitored attainment of the 1997 8-hour ozone NAAQS. Preliminary air quality monitoring data available...

  6. 40 CFR 51.904 - How do the classification and attainment date provisions in section 172(a) of subpart 1 of the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.904 How do the classification and...(h) of the CAA; (2) Transport of ozone and/or precursors into the area is so overwhelming that the contribution of local emissions to observed 8-hour ozone concentration above the level of the NAAQS...

  7. 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...

  8. 40 CFR 51.904 - How do the classification and attainment date provisions in section 172(a) of subpart 1 of the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.904 How do the classification and...(h) of the CAA; (2) Transport of ozone and/or precursors into the area is so overwhelming that the contribution of local emissions to observed 8-hour ozone concentration above the level of the NAAQS...

  9. 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...

  10. 40 CFR 51.904 - How do the classification and attainment date provisions in section 172(a) of subpart 1 of the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.904 How do the classification and...(h) of the CAA; (2) Transport of ozone and/or precursors into the area is so overwhelming that the contribution of local emissions to observed 8-hour ozone concentration above the level of the NAAQS...

  11. 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

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

  12. The High Resolution Tropospheric Ozone Residual

    NASA Technical Reports Server (NTRS)

    Schoeberl, Mark R.

    2006-01-01

    The co-flight of the MLS stratospheric limb sounder and the Ozone Monitoring Instrument (OMI) provides the capability of computing the Tropospheric Ozone Residual (TOR) in much greater detail [Ziemke et al., 2006]. Using forward trajectory calculations of MLS ozone measurements combined with OMI column ozone we have developed a high horizontal resolution tropospheric ozone residual (HTOR) which can provide even more detail than the standard TOR product. HTOR is especially useful for extra-tropical studies of tropospheric ozone transport. We find that both the Pacific pollution corridor (East Asia to Alaska) and the Atlantic pollution corridor (North America east coast to Europe) are also preferred locations for strat-trop folds leading to systematic overestimates of pollution amounts. In fact, fold events appear to dominate extra-tropical Northern Hemisphere day-to-day maps of HTOR. Model estimates of the tropospheric column are in reasonable agreement with the HTOR amounts when offsets due to different tropopause height calculations are taken into consideration.

  13. Climate impact of stratospheric ozone recovery

    NASA Astrophysics Data System (ADS)

    Bekki, S.; Rap, A.; Poulain, V.; Dhomse, S.; Marchand, M.; Lefevre, F.; Forster, P. M.; Szopa, S.; Chipperfield, M. P.

    2013-06-01

    stratospheric ozone depletion has acted to cool the Earth's surface. As the result of the phase-out of anthropogenic halogenated compounds emissions, stratospheric ozone is projected to recover and its radiative forcing (RF-O3 ~ -0.05 W/m2 presently) might therefore be expected to decay in line with ozone recovery itself. Using results from chemistry-climate models, we find that, although model projections using a standard greenhouse gas scenario broadly agree on the future evolution of global ozone, they strongly disagree on RF-O3 because of a large model spread in ozone changes in a narrow (several km thick) layer, in the northern lowermost stratosphere. Clearly, future changes in global stratospheric ozone cannot be considered an indicator of its overall RF. The multi-model mean RF-O3 estimate for 2100 is +0.06 W/m2 but with a range such that it could remain negative throughout this century or change sign and reach up to ~0.25 W/m2.

  14. Total ozone trend significance from space time variability of daily Dobson data

    NASA Technical Reports Server (NTRS)

    Wilcox, R. W.

    1981-01-01

    Estimates of standard errors of total ozone time and area means, as derived from ozone's natural temporal and spatial variability and autocorrelation in middle latitudes determined from daily Dobson data are presented. Assessing the significance of apparent total ozone trends is equivalent to assessing the standard error of the means. Standard errors of time averages depend on the temporal variability and correlation of the averaged parameter. Trend detectability is discussed, both for the present network and for satellite measurements.

  15. An automated ozone photometer

    NASA Technical Reports Server (NTRS)

    Lavelle, Joseph R.

    1988-01-01

    A photometer capable of automatically measuring ozone concentration data to very high resolution during scientific research flights in the earth's atmosphere was developed at the NASA Ames Research Center. This instrument was recently deployed to study the ozone hole over Antarctica. Ozone is detected by absorbing 253.7-nm radiation from an ultraviolet lamp which shines through the sample of air and impinges on a vacuum phototube. A lower output from the phototube indicates more ozone present in the air sample. The photometer employs a CMOS 280 control, data collection, and storage.

  16. A novel tropopause-related climatology of ozone profiles

    NASA Astrophysics Data System (ADS)

    Sofieva, V. F.; Tamminen, J.; Kyrölä, E.; Mielonen, T.; Veefkind, P.; Hassler, B.; Bodeker, G. E.

    2013-08-01

    A new ozone climatology, based on ozonesonde and satellite measurements, spanning the altitude region between the Earth's surface and ~60 km is presented (TpO3 climatology). This climatology is novel in that the ozone profiles are categorized according to calendar month, latitude and local tropopause heights. Compared to the standard latitude-month categorization, this presentation improves the representativeness of the ozone climatology in the upper troposphere and the lower stratosphere (UTLS). The probability distribution of tropopause heights in each latitude-month bin provides additional climatological information and allows transforming/comparing the TpO3 climatology to a standard climatology of zonally mean ozone profiles. The TpO3 climatology is based on high-vertical-resolution measurements of ozone from the satellite-based Stratospheric Aerosol and Gas Experiment II (in 1984 to 2005) and from balloon-borne ozonesondes in 1980 to 2006. The main benefits of the TpO3 climatology are reduced standard deviations on climatological ozone profiles in the UTLS, partial characterization of longitudinal variability, and characterization of ozone profiles in the presence of double tropopauses. The first successful application of the TpO3 climatology as a priori in ozone profiles retrievals from Ozone Monitoring Instrument on board the EOS-Aura satellite shows an improvement of ozone precision in UTLS of up to 10% compared with the use of conventional climatologies. In addition to being advantageous for use as a priori in satellite retrieval algorithms, the TpO3 climatology might be also useful for validating the representation of ozone in climate model simulations.

  17. A novel tropopause-related climatology of ozone profiles

    NASA Astrophysics Data System (ADS)

    Sofieva, V. F.; Tamminen, J.; Kyrölä, E.; Mielonen, T.; Veefkind, P.; Hassler, B.; Bodeker, G. E.

    2014-01-01

    A new ozone climatology, based on ozonesonde and satellite measurements, spanning the altitude region between the earth's surface and ~60 km is presented (TpO3 climatology). This climatology is novel in that the ozone profiles are categorized according to calendar month, latitude and local tropopause heights. Compared to the standard latitude-month categorization, this presentation improves the representativeness of the ozone climatology in the upper troposphere and the lower stratosphere (UTLS). The probability distribution of tropopause heights in each latitude-month bin provides additional climatological information and allows transforming/comparing the TpO3 climatology to a standard climatology of zonal mean ozone profiles. The TpO3 climatology is based on high-vertical-resolution measurements of ozone from the satellite-based Stratospheric Aerosol and Gas Experiment II (in 1984 to 2005) and from balloon-borne ozonesondes from 1980 to 2006. The main benefits of the TpO3 climatology are reduced standard deviations on climatological ozone profiles in the UTLS, partial characterization of longitudinal variability, and characterization of ozone profiles in the presence of double tropopauses. The first successful application of the TpO3 climatology as a priori in ozone profile retrievals from Ozone Monitoring Instrument on board the Earth Observing System (EOS) Aura satellite shows an improvement of ozone precision in UTLS of up to 10% compared with the use of conventional climatologies. In addition to being advantageous for use as a priori in satellite retrieval algorithms, the TpO3 climatology might be also useful for validating the representation of ozone in climate model simulations.

  18. The Characteristics Improvement of Ozone Water Production by Multi-layer Electrodes at Water Electrolysis Cell by Solid Polymer Electrolyte

    NASA Astrophysics Data System (ADS)

    Ohba, Takahiro; Kusunoki, Hironobu; Sunakawa, Daisuke; Araki, Takuto; Onda, Kazuo

    Ozone is recently used for many purposes as an environmental friendly oxidant, so the ozone production device with high ozone concentration and low production energy is desired. One of the candidates for such device is the ozone water production by water electrolysis cell using the solid polymer electrolyte with PbO2 anode catalyst, which has merits to be compact and to produce high-concentration ozone water directly by the deionized water electrolysis. In this study, we have tested ozone water production by changing electrodes and electrolytes constitution in order to improve the ozone production performance. Tested two electrolytes are Nafion117 and a membrane-electrode assembly (MEA) with Pt catalyst on cathode side of Nafion117. Tested two electrodes are mono-layer of Ti expanded metal and four different mesh layers of Ti expanded metal. Ozone water production tests are performed under long-term operations changing temperature and flow rate to optimize experimental conditions. The voltage-current characteristic for electrolysis cell have been improved significantly, when the electrode is four layers of Ti metal and the electrolyte is the MEA with Pt catalyst. The stable ozone water concentration has been obtained by operating the cell for about 8 hours. The optimum temperature and water flow rate for ozone water production are 25˜30° and 33L/h, respectively. Furthermore, the optimum overpotential was measured by a reference electrode at the cathode-side MEA, and the anode catalyst suitable for ozone water production was identified to be βPbO2 by the X ray diffraction pattern.

  19. 40 CFR 51.900 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-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...

  20. 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...

  1. 40 CFR 51.900 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-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...

  2. 77 FR 29904 - Approval and Promulgation of Implementation Plans; Oregon: Infrastructure Requirements for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... Requirements for the 1997 8-Hour Ozone National Ambient Air Quality Standard AGENCY: Environmental Protection... 110(a)(1) and (2) for the 1997 8- hour Ozone and PM 2.5 National Ambient Air Quality Standards...) of the Clean Air Act (CAA) for the National Ambient Air Quality Standard (NAAQS) promulgated...

  3. 40 CFR 51.900 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-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...

  4. Ozone trends in Atlanta, Georgia - Have emission controls been effective?

    NASA Technical Reports Server (NTRS)

    Lindsay, Ronald W.; Richardson, Jennifer L.; Chameldes, William L.

    1989-01-01

    Nine years of summertime ozone data from the Atlanta metropolitan area are analyzed and compared to local emissions of volatile organic carbon and nitrogen oxides. Trends from 1979 to 1987 were studied for the number of days per year ozone exceeded the NAAQS standard, the second-highest ozone level observed per year, and the first quartile summertime average ozone observed, as well as the mean difference between the ozone level observed downwind and upwind of the city. Because this last parameter is sensitive to chemical factors but relatively insensitive to the number of days each year with meteorological conditions conducive to ozone formation, its trend may be best suited for determining how effective emission controls have been in reducing O3 in the Atlanta area. In spite of the fact that sizeable reductions have been claimed for volatile organic carbon emissions over the past several years, the data give no indication that ozone levels have decreased and in fact, imply that summertime ozone production may have increased. The results imply that either emissions have not decreased as much as has been claimed or that ozone is not sensitive to anthropogenic volatile organic carbon emissions.

  5. 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.

  6. 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…

  7. 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.

  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. 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 ...

  11. 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.

  12. An evaluation of electrochemical concentration Cell (ECC) sonde measurements of atmospheric ozone

    NASA Technical Reports Server (NTRS)

    Geraci, M. J.; Luers, J. K.

    1978-01-01

    Using Dobson spectrophotometer measurements of total ozone as a comparison, an analysis of the electrochemical concentration cell (ECC) ozonesonde's measurement accuracy is presented. Days of conjunctive ECC-Dobson observations (from 1970 to 1976 at Wallops Flight Center) provide a set of 123 pairs of total ozone values. Sample set statistics are generated with means and standard deviations of total ozone values and differences being noted. An in-depth study of factors such as time assumptions used in calculating residual ozone, and other possible sources of errors are examined. A study of ECC ozone profiles is also presented with an evaluation of sonde measurement of seasonal trends, altitude or peak ozone concentration, and other important ozone parameters. Short-period changes in total ozone using Dobson data during the observational period are also described.

  13. 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.

  14. Long-Term Ozone Exposure Attenuates 1-Nitronaphthalene–Induced Cytotoxicity in Nasal Mucosa

    PubMed Central

    Lee, Myong Gyong; Wheelock, Åsa M.; Boland, Bridget; Plopper, Charles G.

    2008-01-01

    1-Nitronaphthalene (1-NN) and ozone are cytotoxic air pollutants commonly found as components of photochemical smog. The mechanism of toxicity for 1-NN involves bioactivation by cytochrome P450s and subsequent adduction to proteins. Previous studies have shown that 1-NN toxicity in the lung is considerably higher in rats after long-term exposure to ozone compared with the corresponding filtered air–exposed control rats. The aim of the present study was to establish whether long-term exposure to ozone alters the susceptibility of nasal mucosa to the bioactivated toxicant, 1-NN. Adult male Sprague-Dawley rats were exposed to filtered air or 0.8 ppm ozone for 8 hours per day for 90 days, followed by a single treatment with 0, 12.5, or 50.0 mg/kg 1-NN by intraperitoneal injection. The results of the histopathologic analyses show that the nasal mucosa of rats is a target of systemic 1-NN, and that long-term ozone exposure markedly lessens the severity of injury, as well as the protein adduct formation by reactive 1-NN metabolites. The antagonistic effects were primarily seen in the nasal transitional epithelium, which corresponds to the main site of histologic changes attributed to ozone exposure (goblet cell metaplasia and hyperplasia). Long-term ozone exposure did not appear to alter susceptibility to 1-NN injury in other nasal regions. This study shows that long-term ozone exposure has a protective effect on the susceptibility of nasal transitional epithelium to subsequent 1-NN, a result that clearly contrasts with the synergistic toxicological effect observed in pulmonary airway epithelium in response to the same exposure regimen. PMID:17901409

  15. 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.…

  16. 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)

  17. 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 ...

  18. The ASSET intercomparison of ozone analyses: method and first results

    NASA Astrophysics Data System (ADS)

    Geer, A. J.; Lahoz, W. A.; Bekki, S.; Bormann, N.; Errera, Q.; Eskes, H. J.; Fonteyn, D.; Jackson, D. R.; Juckes, M. N.; Massart, S.; Peuch, V.-H.; Rharmili, S.; Segers, A.

    2006-12-01

    This paper aims to summarise the current performance of ozone data assimilation (DA) systems, to show where they can be improved, and to quantify their errors. It examines 11 sets of ozone analyses from 7 different DA systems. Two are numerical weather prediction (NWP) systems based on general circulation models (GCMs); the other five use chemistry transport models (CTMs). The systems examined contain either linearised or detailed ozone chemistry, or no chemistry at all. In most analyses, MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) ozone data are assimilated; two assimilate SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography) observations instead. Analyses are compared to independent ozone observations covering the troposphere, stratosphere and lower mesosphere during the period July to November 2003. Biases and standard deviations are largest, and show the largest divergence between systems, in the troposphere, in the upper-troposphere/lower-stratosphere, in the upper-stratosphere and mesosphere, and the Antarctic ozone hole region. However, in any particular area, apart from the troposphere, at least one system can be found that agrees well with independent data. In general, none of the differences can be linked to the assimilation technique (Kalman filter, three or four dimensional variational methods, direct inversion) or the system (CTM or NWP system). Where results diverge, a main explanation is the way ozone is modelled. It is important to correctly model transport at the tropical tropopause, to avoid positive biases and excessive structure in the ozone field. In the southern hemisphere ozone hole, only the analyses which correctly model heterogeneous ozone depletion are able to reproduce the near-complete ozone destruction over the pole. In the upper-stratosphere and mesosphere (above 5 hPa), some ozone photochemistry schemes caused large but easily remedied biases. The diurnal cycle of ozone in the

  19. 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

  20. 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

  1. 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

  2. A Total Ozone Dependent Ozone Profile Climatology Based on Ozone-Sondes and Aura MLS Data

    NASA Astrophysics Data System (ADS)

    Labow, G. J.; McPeters, R. D.; Ziemke, J. R.

    2014-12-01

    A new total ozone-based ozone profile climatology has been created for use in satellite and/or ground based ozone retrievals. This climatology was formed by combining data from the Microwave Limb Sounder (MLS) with data from balloon sondes and binned by zone and total ozone. Because profile shape varies with total column ozone, this climatology better captures the ozone variations than the previously used seasonal climatologies, especially near the tropopause. This is significantly different than ozone climatologies used in the past as there is no time component. The MLS instrument on Aura has excellent latitude coverage and measures ozone profiles daily from the upper troposphere to the lower mesosphere at ~3.5 km resolution. Almost a million individual MLS ozone measurements are merged with data from over 55,000 ozonesondes which are then binned as a function of total ozone. The climatology consists of average ozone profiles as a function of total ozone for six 30 degree latitude bands covering altitudes from 0-75 km (in Z* pressure altitude coordinates). This new climatology better represents the profile shape as a function of total ozone than previous climatologies and shows some remarkable and somewhat unexpected correlations between total ozone and ozone in the lower altitudes, particularly in the lower and middle troposphere. These data can also be used to infer biases and errors in either the MLS retrievals or ozone sondes.

  3. 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

  4. Low density solid ozone

    SciTech Connect

    Teolis, B. D.; Fama, M.; Baragiola, R. A.

    2007-08-21

    We report a very low density ({approx}0.5 g/cm{sup 3}) structure of solid ozone. It is produced by irradiation of solid oxygen with 100 keV protons at 20 K followed by heating to sublime unconverted oxygen. Upon heating to 47 K the porous ozone compacts to a density of {approx}1.6 g/cm{sup 3} and crystallizes. We use a detailed analysis of the main infrared absorption band of the porous ozone to interpret previous research, where solid oxygen was irradiated by UV light and keV electrons.

  5. 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.

  6. A video atlas of TOMS ozone data, 1978-88

    NASA Astrophysics Data System (ADS)

    Chesters, D.; Krueger, A. J.

    1989-12-01

    The Total Ozone Mapping Spectrometer (TOMS), on-board NASA's Nimbus-7 weather satellite, has been observing ozone over the earth once daily for the last 10 yr. A time-lapse atlas of 3440 color-coded images drawn from the TOMS archive from 1978 to 1988 has been visualized on a standard VHS videotape that is now available from NASA. The rapid and complex ozone variations presented demonstrate the difficulty of separating man-induced climate changes from natural variability. This article presents a few images from the atlas and describes interesting features in the animation, such as the correlation between ozone and 'the weather', and the recent deepening of the annual ozone hole over the South Pole. Originally intended as a browsing tool for the TOMS digital database, the videotape is a vivid presentation of the earth's atmospheric dynamics and chemistry that is recommended for scientists, educators, policy makers, and citizens concerned about the global environment.

  7. A video atlas of TOMS ozone data, 1978-88

    NASA Technical Reports Server (NTRS)

    Chesters, D.; Krueger, A. J.

    1989-01-01

    The Total Ozone Mapping Spectrometer (TOMS), on-board NASA's Nimbus-7 weather satellite, has been observing ozone over the earth once daily for the last 10 yr. A time-lapse atlas of 3440 color-coded images drawn from the TOMS archive from 1978 to 1988 has been visualized on a standard VHS videotape that is now available from NASA. The rapid and complex ozone variations presented demonstrate the difficulty of separating man-induced climate changes from natural variability. This article presents a few images from the atlas and describes interesting features in the animation, such as the correlation between ozone and 'the weather', and the recent deepening of the annual ozone hole over the South Pole. Originally intended as a browsing tool for the TOMS digital database, the videotape is a vivid presentation of the earth's atmospheric dynamics and chemistry that is recommended for scientists, educators, policy makers, and citizens concerned about the global environment.

  8. Minireview: the health implications of water treatment with ozone

    SciTech Connect

    Carmichael, N.G.; Winder, C.; Borges, S.H.; Backhouse, B.L.; Lewis, P.D.

    1982-01-11

    Ozone is a highly efficient disinfectant which may have significant advantages in water treatment compared to chlorine. It has, however, been shown that mutagenic and possibly carcinogenic byproducts may be produced under certain conditions of ozonation. Light chlorination following ozonization may meet the highest standards of disinfection. In addition the destruction of much of the organic matter by prior ozone treatment may well result in less harmful chlorinated and brominated products in the finished water. In many cases ozone treatment alone may suffice. It would be desirable to test with long term in vivo experiments which of the alternatives produces the best combination of microbiologically clean and pleasant water with minimum mutagenic and carcinogenic effect.

  9. USER'S GUIDE FOR EXECUTING OZIPM-4 (OZONE ISOPLETH PLOTTING WITH OPTIONAL MECHANISMS, VERSION 4) WITH CBM-IV (CARBON-BOND MECHANISMS-IV) OR OPTIONAL MECHANISMS. VOLUME 1. DESCRIPTION OF THE OZONE ISOPLETH PLOTTING PACKAGE. VERSION 4

    EPA Science Inventory

    An updated version of the Ozone Isopleth Plotting Program has been developed for use with EKMA to calculate emission reductions needed to achieve the air quality standard for ozone. The program, called OZIPM-IV (Ozone Isopleth Plotting with Optional Mechanisms - Version IV), cont...

  10. 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

  11. Forecasting of daily total atmospheric ozone in Isfahan.

    PubMed

    Yazdanpanah, H; Karimi, M; Hejazizadeh, Z

    2009-10-01

    A neural network combined to an artificial neural network model is used to forecast daily total atmospheric ozone over Isfahan city in Iran. In this work, in order to forecast the total column ozone over Isfahan, we have examined several neural networks algorithms with different meteorological predictors based on the ozone-meteorological relationships with previous day's ozone value. The meteorological predictors consist of temperatures (dry and dew point) and geopotential heights at standard levels of 100, 50, 30, 20 and 10 hPa with their wind speed and direction. These data together with previous day total ozone forms the input matrix of the neural model that is based on the back propagation algorithm (BPA) structure. The output matrix is the daily total atmospheric ozone. The model was build based on daily data from 1997 to 2004 obtained from Isfahan ozonometric station data. After modeling these data we used 3 year (from 2001 to 2003) of daily total ozone for testing the accuracy of model. In this experiment, with the final neural network, the total ozone are fairly well predicted, with an Agreement Index 76%. PMID:18843548

  12. Response of Federal Land Management Agencies to ozone impacts on vegetation

    SciTech Connect

    Musselman, R.C.; Fisher, R.W.

    1999-07-01

    The FLAG (Federal Land Manager's AQRV WorkGroup) Ozone Subgroup was organized to compile information known about response of vegetation to ozone in federally managed parks, forests, and wildlife refuges; to document areas of agreement among federal agencies regarding identification of ozone sensitive Air Quality Related Values (AQRVs); and standardize agency responses to New Source Review (NSR) permit applications. Subgroup members included air resource managers and ozone effects scientists from several agencies that manage federal lands. The subgroup identified sensitive AQRV receptors, determined information needed to evaluate permit applications under the NSR process, determined the form of an ozone parameter to use to relate plant response to ambient ozone, and agreed on specific definitions for vegetation injury and damage from ozone. The subgroup developed specific protocols for federal agencies to follow in response to NSR permit applications. These protocols were based on (1) ambient levels of ozone as measured by the W126 ozone metric and the number of peak ozone concentrations $100 ppb (N100), and (2) the presence or absence of ozone sensitive plant species and ozone-induced damage to vegetation.

  13. EVALUATION OF OZONE EXPOSURE INDICES FOR RELATING EXPOSURE TO PLANT PRODUCTION AND FOR ESTIMATING AGRICULTURAL LOSSES

    EPA Science Inventory

    The objective of the report is: (1) to compare alternative ozone exposure indices that relate well to plant response and are useful in developing future standards for ozone; (2) to estimate standard errors and confidence intervals of regression coefficients and exposure levels of...

  14. Increasing Springtime Ozone Mixing Ratios in the Free Troposphere Over Western North America

    NASA Technical Reports Server (NTRS)

    Cooper, O. R.; Parrish, D. D.; Stohl, A.; Trainer, M.; Nedelec, P.; Thouret, V.; Cammas, J. P.; Oltmans, S. J.; Johnson, B. J.; Tarasick, D.; Leblanc, T.; McDermid, I. S.; Jaffe, D.; Gao, R.; Stith, J.; Ryerson, T.; Aikin, K.; Campos, T.; Weinheimer, A.; Avery, M. A.

    2010-01-01

    In the lowermost layer of the atmosphere - the troposphere - ozone is an important source of the hydroxyl radical, an oxidant that breaks down most pollutants and some greenhouse gases. High concentrations of tropospheric ozone are toxic, however, and have a detrimental effect on human health and ecosystem productivity1. Moreover, tropospheric ozone itself acts as an effective greenhouse gas. Much of the present tropospheric ozone burden is a consequence of anthropogenic emissions of ozone precursors resulting in widespread increases in ozone concentrations since the late 1800s. At present, east Asia has the fastest-growing ozone precursor emissions. Much of the springtime east Asian pollution is exported eastwards towards western North America. Despite evidence that the exported Asian pollution produces ozone, no previous study has found a significant increase in free tropospheric ozone concentrations above the western USA since measurements began in the late 1970s. Here we compile springtime ozone measurements from many different platforms across western North America. We show a strong increase in springtime ozone mixing ratios during 1995-2008 and we have some additional evidence that a similar rate of increase in ozone mixing ratio has occurred since 1984. We find that the rate of increase in ozone mixing ratio is greatest when measurements are more heavily influenced by direct transport from Asia. Our result agrees with previous modelling studies, which indicate that global ozone concentrations should be increasing during the early part of the twenty-first century as a result of increasing precursor emissions, especially at northern mid-latitudes, with western North America being particularly sensitive to rising Asian emissions. We suggest that the observed increase in springtime background ozone mixing ratio may hinder the USA s compliance with its ozone air quality standard.

  15. Altitude troposphere ozone profiles over Kyiv-Goloseyev station by simultaneous Umkehr and FTIR observations

    NASA Astrophysics Data System (ADS)

    Milinevsky, Gennadi; Shavrina, Angelina; Udodov, Evgeny; Liptuga, Anatoly; Kyslyi, Volodymyr; Danylevsky, Vassyl; Kravchenko, Volodymyr; Ivanov, Yuri; Synyavski, Ivan; Romanyuk, Yaroslav; Pavlenko, Yakov; Veles, Oleksandr

    2016-04-01

    Total ozone column and ozone profile data have been obtained from both: (1) standard Dobson measurements and Umkehr method, and (2) using modeling of the ozone absorption spectral band profile near 9.6 microns with the MODTRAN4.3 Atmospheric Radiation Transfer Model based on the HITRAN molecular absorption database from Fourier transform infrared spectroscopy (FTIR) observations. The simultaneous ground-based Dobson/Umkehr and FTIR ozone observations have been performed in 2014-2015 at the mid-latitude Kyiv-Goloseyev KGV GAW station for joint altitude troposphere ozone profiles analysis. To retrieve ozone column estimates and ozone profiles from FTIR observations, we used the satellite Aqua-AIRS water vapor, temperature and ozone profiles, and the simultaneous with FTIR observations the Umkehr ozone profiles and surface ozone measurements as input a priori information for the MODTRAN4.3 model. The altitude ozone profiles retrieved from Umkehr method and satellite measurements are in good correspondence in stratosphere layer. However the troposphere part of ozone profiles is uncertain and reproduced with large errors. Therefore we use the MODTRAN4.3 model for interpretation of observed FTIR absorption spectrum to retrieve and improve the troposphere part of ozone altitude distribution. The synergy of Umkehr, satellite and FTIR simultaneous observations including surface ozone measurements allows rendering the ozone profile features in troposphere that indicate the stratosphere-troposphere exchange processes. Season ozone profile variations observed from Umkehr measurements are discussed as well. This work was partly supported by the Polar FORCeS project no. 4012 of the Australian Antarctic Science Program.

  16. 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.

  17. OTAG & the FACA ozone, PM, and regional haze process: Forces that can tighten NO{sub x} regulations

    SciTech Connect

    Booth, C.M.

    1995-12-31

    THe Ozone Transport Assessment Group (OTAG) and the Federal Advisory Committee Act (FACA) ozone, particulate matter (PM), and the regional haze process are outlined. These are the forces that can tighten NO{sub x} regulations. The following topics are discussed: basic thrusts, OTAG activities, goals, the Northeastern Ozone Transport Region (NEOTR), potential regulatory scenarios, practical roles, subcommittee actions, possible changes in the National Ambient Air Quality Standards (NAAQS) for ozone, and implications of proposed changes.

  18. 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.

  19. MULTIPOLLUTANT METHODS - METHODS FOR OZONE AND OZONE PRECURSORS

    EPA Science Inventory

    This task involves the development and testing of methods for monitoring ozone and compounds associated with the atmospheric chemistry of ozone production both as precursors and reaction products. Although atmospheric gases are the primary interest, separation of gas and particl...

  20. 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.

  1. 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

  2. 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.

  3. 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…

  4. 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 ...

  5. 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...

  6. "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...

  7. An automated ozone photometer

    NASA Technical Reports Server (NTRS)

    Lavelle, Joseph R.

    1988-01-01

    A photometer capable of automatically measuring ozone concentration data to very high resolution during scientific research flights in the Earth's atmosphere was developed at NASA Ames Research Center. This instrument was recently deployed to study the ozone hole over Antarctica. Ozone is detected by absorbing 253.7-nm radiation from an ultraviolet lamp which shines through the sample of air and impinges on a vacuum phototube. A lower output from the phototube indicates more ozone present in the air sample. The photometer employs a CMOS Z80 microprocessor with an STD bus system for experiment control, data collection, and storage. Data are collected and stored in nonvolatile memory for experiments lasting up to 8 hr. Data are downloaded to a portable ground-support computer and processed after the aircraft lands. An independent single-board computer in the STD bus also calculates ozone concentration in real time with less resolution than the CMOS Z80 system, and sends this value to a cockpit meter to aid the pilot in navigation.

  8. Ozone risk for crops and pastures in present and future climates

    NASA Astrophysics Data System (ADS)

    Fuhrer, Jürg

    2009-02-01

    most at risk from ozone in a future climate and to set robust effect-based ozone standards.

  9. Tropospheric ozone and ozone profiles retrieved from GOME-2 and their validation

    NASA Astrophysics Data System (ADS)

    Miles, G. M.; Siddans, R.; Kerridge, B. J.; Latter, B. G.; Richards, N. A. D.

    2015-01-01

    This paper describes and assesses the performance of the RAL (Rutherford Appleton Laboratory) ozone profile retrieval scheme for the Global Ozone Monitoring Experiment 2 (GOME-2) with a focus on tropospheric ozone. Developments to the scheme since its application to GOME-1 measurements are outlined. These include the approaches developed to account sufficiently for UV radiometric degradation in the Hartley band and for inadequacies in knowledge of instrumental parameters in the Huggins bands to achieve the high-precision spectral fit required to extract information on tropospheric ozone. The assessment includes a validation against ozonesondes (sondes) sampled worldwide over 2 years (2007-2008). Standard deviations of the ensemble with respect to the sondes are considerably lower for the retrieved profiles than for the a priori, with the exception of the lowest subcolumn. Once retrieval vertical smoothing (averaging kernels) has been applied to the sonde profiles there is a retrieval bias of 6% (1.5 DU) in the lower troposphere, with smaller biases in the subcolumns above. The bias in the troposphere varies with latitude. The retrieval underestimates lower tropospheric ozone in the Southern Hemisphere (SH) (15-20% or ~ 1-3 DU) and overestimates it in the Northern Hemisphere (NH) (10% or 2 DU). The ability of the retrieval to reflect the geographical distribution of lower tropospheric ozone, globally (rather than just ozonesonde launch sites) is demonstrated by comparison with the chemistry transport model TOMCAT. For a monthly mean of cloud-cleared GOME-2 pixels, a correlation of 0.66 is found between the retrieval and TOMCAT sampled accordingly, with a bias of 0.7 Dobson Units. GOME-2 estimates higher concentrations in NH pollution centres but lower ozone in the Southern Ocean and South Pacific, which is consistent with the comparison to ozonesondes.

  10. High Concentration of Surface Ozone Observed along the Khumbu Valley Nepal April 2007

    NASA Astrophysics Data System (ADS)

    Semple, J.; Moore, K.

    2009-12-01

    Increasing air pollution in Southeast Asia has the potential for dramatic impacts on the population and climate in relatively pristine regions such as the Himalaya. Recent measurements near Mount Everest indicate the presence of elevated levels of ozone at elevations from 5000m to 9000m that are the result of both the long-range transport of tropospheric pollutants from Southeast Asia as well as the descent of ozone-rich stratospheric air. Here we report on the first surface ozone concentration transect in the Mount Everest region. The data collected at elevations from 2900m to 5200m indicate an increase in concentration with height as well as 8-hour average exposures in excess of 140ppb. Satellite data and meteorological diagnostics suggest a stratospheric source for the high levels observed. The majority of values observed exceed guidelines for human exposure and therefore are of a magnitude to suggest that they are of physiological relevance. Potential vorticity (PVU-shading and contours) and horizontal wind (vectors-m/s) from the ERA-I Reanalysis on the 330K potential temperature surface at 06 UTC (approximately noon local time) on April 12 2007 showing the tropopause fold that resulted in the high surface ozone concentration observed along the Khumbu Valley near Mount Everest. The 1 PVU contour is indicated by the thin black line. The Tibetan Plateau is indicated as is the location of Mount Everest by the ‘+’.

  11. 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

  12. 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

  13. Ames ER-2 ozone measurements

    NASA Technical Reports Server (NTRS)

    Pearson, R., Jr.; Vedder, James F.; Starr, W. L.

    1990-01-01

    The objective of this research is to study ozone (O3) in the stratosphere. Measurements of the ozone mixing ratio at 1 s intervals are obtained with an ultraviolet photometer which flies on the ER-2 aircraft. The photometer determines the amount of ozone in air by measuring the transmission of ultraviolet light through a fixed path with and without ambient O3 present.

  14. Indoor ozone concentrations: Ventilation rate impacts and mechanisms of outdoor concentration attenuation

    SciTech Connect

    Cano-Ruiz, J.A.; Modera, M.P.; Nazaroff, W.W.

    1992-07-01

    The classification of outdoor (ambient) air as fresh for the purposes of ventilation is not always appropriate, particularly in urban areas. In many cities of the world, urban air frequently violates health-based air quality standards due to high ozone concentrations. The degree of protection from exposure to ozone offered by the indoor environment depends on the relationship between indoor and outdoor ozone levels. Existing concentration data indicates that indoor/outdoor ozone ratios range between 10 and 80%. This paper analyzes several of the key issues influencing indoor ozone concentrations, including: (1) the degree of penetration of outdoor ozone indoors, (2) removal within the indoor environment (removal at surfaces and within air distribution systems), and (3) the correlation in time between outdoor ozone levels and ventilation rates. A model for calculating the degree of ozone removal in typical building leaks and air distribution systems is described and applied to a range of typical cases. This model indicates that the degree of removal is minimal for most wooden building cracks, but could be significant in leaks in concrete or brick structures, and is strongly dependent on the lining material for air distribution systems. Indoor ozone exposure estimates based on hourly outdoor ozone monitoring data and hour-by-hour weather-based simulations of infiltration rates and building operation are reported for a few residential scenarios. These estimates serve as a basis for exploring the impact of energy-efficient ventilation strategies on indoor ozone exposures.

  15. 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.

  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. Comparison of Suomi-NPP OMPS total column ozone with Brewer and Dobson spectrophotometers measurements

    NASA Astrophysics Data System (ADS)

    Bai, Kaixu; Liu, Chaoshun; Shi, Runhe; Gao, Wei

    2015-09-01

    The objective of this study is to evaluate the accuracy of the daily nadir total column ozone products derived from the nadir mapper instrument on the Ozone Mapping and Profiler Suite (OMPS) flying onboard the Suomi National Polar-orbiting Partnership satellite (S-NPP) launched as a part of the Joint Polar Satellite System (JPSS) program between NOAA and NASA. Since NOAA is already operationally processing OMPS nadir total ozone products, evaluations were made in this study on the total column ozone research products generated by NASA's science team, utilizing the latest version of their Backscatter Ultraviolet (BUV) retrieval algorithms, to provide insight into the performance of the operation system. Comparisons were made with globally distributed ground-based Brewer and Dobson spectrophotometer total column ozone measurements. Linear regressions show fair agreement between OMPS and ground-based total column ozone measurements with a root-mean-square error (RMSE) of approximately 3% (10 DU). The comparison results indicate that the OMPS total column ozone data are 0.59% higher than the Brewer measurements with a standard deviation of 2.82% while 1.09% higher than the Dobson measurements with a standard deviation of 3.27%. Additionally, the variability of relative differences between OMPS and ground total column ozone were analyzed as a function of latitude, time, viewing geometry, and total column ozone value. Results show a 2% bias over most latitudes and viewing conditions when total column ozone value varies between 220 DU and 450 DU.

  18. 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.

  19. ADEOS Total Ozone Mapping Spectrometer (TOMS) Data Products User's Guide

    NASA Technical Reports Server (NTRS)

    Krueger, A.; Bhartia, P. K.; McPeters, R.; Herman, J.; Wellemeyer, C.; Jaross, G.; Seftor, C.; Torres, O.; Labow, G.; Byerly, W.; Moy, L.; Taylor, S.; Swissler, T.; Cebula, R.

    1998-01-01

    Two data products from the Total Ozone Mapping Spectrometer (ADEOS/TOMS) have been archived at the Distributed Active Archive Center, in the form of Hierarchical Data Format files. The ADEOS/ TOMS began taking measurements on September 11, 1996, and ended on June 29, 1997. The instrument measured backscattered Earth radiance and incoming solar irradiance; their ratio was used in ozone retrievals. Changes in the reflectivity of the solar diffuser used for the irradiance measurement were monitored using a carousel of three diffusers, each exposed to the degrading effects of solar irradiation at different rates. The algorithm to retrieve total column ozone compares measured Earth radiances at sets of three wavelengths with radiances calculated for different total ozone values, solar zenith angles, and optical paths. The initial error in the absolute scale for TOMS total ozone is 3 percent, the one standard deviation random error is 2 percent, and the drift is less than 0.5 percent over the 9-month data record. The Level 2 product contains the measured radiances, the derived total ozone amount, and reflectivity information for each scan position. The Level 3 product contains daily total ozone and reflectivity in a 1-degree latitude by 1.25 degrees longitude grid. The Level 3 files containing estimates of UVB at the Earth surface and tropospheric aerosol information will also be available. Detailed descriptions of both HDF data files and the CDROM product are provided.

  20. 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.

  1. 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.

  2. 75 FR 3183 - Approval and Promulgation of Air Quality Implementation Plan: Kentucky; Approval Section 110(a)(1...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-20

    ...EPA is proposing to approve a revision to the Kentucky State Implementation Plan (SIP) concerning the maintenance plan addressing the 1997 8-hour ozone standard for the Owensboro 8-hour ozone attainment area, which comprises Daviess County and a portion of Hancock County (hereafter referred to as the ``Owensboro Area''). This maintenance plan was submitted to EPA on May 27, 2008, by the......

  3. 75 FR 45568 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-03

    ... 30, 2004 (69 FR 23857), EPA published its air quality designations and classifications for the 1997 8... Quality Planning Purposes; Tennessee: Knoxville; Determination of Attainment for the 1997 8-Hour Ozone... attained the 1997 8-hour ozone national ambient air quality standards (NAAQS) based on quality...

  4. 40 CFR 93.101 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... data determined by EPA to meet the requirements of 40 CFR part 58 that indicate attainment of the... pursuant to 23 CFR part 450. FTA means the Federal Transit Administration of DOT. Highway project is an... quality standard codified at 40 CFR 50.9. (2) 8-hour ozone NAAQS means the 8-hour ozone national...

  5. 40 CFR 93.101 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... data determined by EPA to meet the requirements of 40 CFR part 58 that indicate attainment of the... pursuant to 23 CFR part 450. FTA means the Federal Transit Administration of DOT. Highway project is an... quality standard codified at 40 CFR 50.9. (2) 8-hour ozone NAAQS means the 8-hour ozone national...

  6. 40 CFR 51.903 - How do the classification and attainment date provisions in section 181 of subpart 2 of the CAA...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 8-hour Ozone National Ambient Air Quality Standard § 51.903 How do the classification and attainment... area shall be calculated using the three most recent years of air quality data. For each area... for 8-Hour Ozone NAAQS for Areas Subject to § 51.902(a) Area class 8-hourdesign value (ppm...

  7. 40 CFR 51.903 - How do the classification and attainment date provisions in section 181 of subpart 2 of the CAA...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 8-hour Ozone National Ambient Air Quality Standard § 51.903 How do the classification and attainment... area shall be calculated using the three most recent years of air quality data. For each area... for 8-Hour Ozone NAAQS for Areas Subject to § 51.902(a) Area class 8-hourdesign value (ppm...

  8. 40 CFR 51.903 - How do the classification and attainment date provisions in section 181 of subpart 2 of the CAA...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 8-hour Ozone National Ambient Air Quality Standard § 51.903 How do the classification and attainment... area shall be calculated using the three most recent years of air quality data. For each area... for 8-Hour Ozone NAAQS for Areas Subject to § 51.902(a) Area class 8-hourdesign value (ppm...

  9. 76 FR 17373 - Approval and Promulgation of Implementation Plans; Nevada; Determination of Attainment for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-29

    ... nonattainment area has attained the 1997 8-hour ozone national ambient air quality standards (NAAQS). This... monitoring period. Preliminary air quality monitoring data available for 2010 are consistent with continued... Attainment for the Clark County 8-Hour Ozone Nonattainment Area AGENCY: Environmental Protection Agency...

  10. 40 CFR 51.903 - How do the classification and attainment date provisions in section 181 of subpart 2 of the CAA...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 8-hour Ozone National Ambient Air Quality Standard § 51.903 How do the classification and attainment... area shall be calculated using the three most recent years of air quality data. For each area... for 8-Hour Ozone NAAQS for Areas Subject to § 51.902(a) Area class 8-hourdesign value (ppm...

  11. 75 FR 53219 - Approval and Promulgation of Air Quality Implementation Plans; Connecticut; Determination of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... significant regulatory actions based on health or safety risks subject to Executive Order 13045 (62 FR 19885...; Determination of Attainment of the 1997 Ozone Standard for the Greater Connecticut Area AGENCY: Environmental... moderate 1997 8-hour ozone nonattainment area has attained the 1997 8-hour National Ambient Air...

  12. 75 FR 14077 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-24

    ..., this redesignation is for the 1997 8-hour ozone designations finalized in April 30, 2004 (69 FR 23857... EPA's Phase 1 Implementation Rule for the 8-hour Ozone Standard. (69 FR 23951, April 30, 2004). South... based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997); Is not...

  13. 77 FR 36404 - Approval and Promulgation of Air Quality Implementation Plans; Massachusetts; Determination of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-19

    ... significant regulatory actions based on health or safety risks subject to Executive Order 13045 (62 FR 19885...; Determination of Attainment of the 1997 Ozone Standard for the Western Massachusetts Nonattainment Area AGENCY... Massachusetts) moderate 1997 8-hour ozone nonattainment area has attained the 1997 8-hour National Ambient...

  14. 40 CFR 52.2354 - Interstate transport.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Section 110(a)(2)(D)(i) requirements for the 1997 8-hour ozone and PM2.5 standards. Section XXIII... requirements of the Clean Air Act Section 110(a)(2)(D)(i) for the 8-hour ozone and PM2.5 NAAQS promulgated...

  15. 77 FR 66921 - Approval and Promulgation of Air Quality Implementation Plans; New Hampshire; Reasonably...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-08

    ... being in nonattainment of the 1997 8-hour ozone NAAQS (69 FR 23858). In New Hampshire, the Boston... made further revisions to the ozone NAAQS setting the 8-hour standard at 0.075 ppm (73 FR 16436, March..., 2006, EPA issued four new CTGs which states were required to address by October 5, 2007 (71 FR...

  16. 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.

  17. Total Ozone Prediction: Stratospheric Dynamics

    NASA Technical Reports Server (NTRS)

    Jackman, Charles H.; Kawa, S. Ramdy; Douglass, Anne R.

    2003-01-01

    The correct prediction of total ozone as a function of latitude and season is extremely important for global models. This exercise tests the ability of a particular model to simulate ozone. The ozone production (P) and loss (L) will be specified from a well- established global model and will be used in all GCMs for subsequent prediction of ozone. This is the "B-3 Constrained Run" from M&MII. The exercise mostly tests a model stratospheric dynamics in the prediction of total ozone. The GCM predictions will be compared and contrasted with TOMS measurements.

  18. Assimilation of Satellite Ozone Observations

    NASA Technical Reports Server (NTRS)

    Stajner, I.; Winslow, N.; Wargan, K.; Hayashi, H.; Pawson, S.; Rood, R.

    2003-01-01

    This talk will discuss assimilation of ozone data from satellite-borne instruments. Satellite observations of ozone total columns and profiles have been measured by a series of Total Ozone Mapping Spectrometer (TOMS), Solar Backscatter Ultraviolet (SBUV) instruments, and more recently by the Global Ozone Monitoring Experiment. Additional profile data are provided by instruments on NASA's Upper Atmosphere Research Satellite and by occultation instruments on other platforms. Instruments on Envisat' and future EOS Aura satellite will supply even more comprehensive data about the ozone distribution. Satellite data contain a wealth of information, but they do not provide synoptic global maps of ozone fields. These maps can be obtained through assimilation of satellite data into global chemistry and transport models. In the ozone system at NASA's Data Assimilation Office (DAO) any combination of TOMS, SBUV, and Microwave Limb sounder (MLS) data can be assimilated. We found that the addition of MLS to SBUV and TOMS data in the system helps to constrain the ozone distribution, especially in the polar night region and in the tropics. The assimilated ozone distribution in the troposphere and lower stratosphere is sensitive also to finer changes in the SBUV and TOMS data selection and to changes in error covariance models. All results are established by comparisons of assimilated ozone with independent profiles from ozone sondes and occultation instruments.

  19. Influence of baseline ozone on surface air quality in the western U.S

    NASA Astrophysics Data System (ADS)

    Jaffe, D. A.; Downey, N.

    2011-12-01

    As the ozone air quality standard is made more stringent, cities, counties and states will need a better understanding of the sources of ozone. While Eulerian models can provide important indications of the sources, they are often challenged by episodic emissions (eg wildfires), interannual variability and/or coarse model resolution. These challenges are especially problematic in the western United States. Thus we need improved tools to directly use available observations to better understand and identify ozone sources. In this study we examine the relationship between measured free tropospheric/baseline ozone and surface ozone at several receptor sites in the western U.S. Our focus is on air quality sites in the Pacific Northwest and Rocky Mtn region that exceed current or new air quality standards that have been proposed. Elevated sites in the Rocky Mtns are exposed to high ozone from the free troposphere. Significant interannual variations occur in spring, due to variations in baseline ozone, and in summer, due to variations in wildfires. In the Rocky Mtn region there are significant correlations between the surface and free tropospheric mixing ratios using both daily and monthly means for spring and summer months (see Jaffe 2011; DOI: 10.1021/es1028102). This implies that free tropospheric ozone mixes down and frequently contributes to elevated ozone at the surface. In the Pacific Northwest, we are using data from suburban and rural monitoring locations to identify ozone from local and non-local sources. The approach for both the Rocky Mtn and Pacific Northwest sites is to develop a statistical model for ozone using all available observations, (e.g. PM, meteorology, satellite data and trajectories) to quantify the variable contribution from baseline ozone. The statistical model can then be evaluated against actual observations of baseline ozone. The statistical model can also be useful to help identify "exceptional events" as defined by the US EPA.

  20. Spatial analysis of ozone in Atlanta: Regulatory and epidemiologic implications

    SciTech Connect

    Butler, A.J.; Mulholland, J.A.; Wilkinson, J.G.; Russell, A.G.; Tolbert, P.E.

    1998-12-31

    Relationships between ambient levels of selected air pollutants and pediatric asthma exacerbation in Atlanta were studied retrospectively. As a part of this study, spatial distributions of ambient ozone concentrations in the twenty-county Atlanta metropolitan area during the summers of 1993, 1994 and 1995 were estimated and assessed. A universal kriging procedure was used for spatial interpolation of aerometric monitoring station data. In this paper, the spatial distributions of ozone are described, and regulatory and epidemiologic implications are discussed. For the study period, the Atlanta ozone nonattainment area based on the one-hour, exceedance-based standard of 0.12 ppm is estimated to expand from 56 percent of the Atlanta MSA by area and 71 percent by population to 88 percent by area and 96 percent by population under the new eight-hour, concentration-based standard of 0.08 ppm. Regarding asthma exacerbation, a 4 percent increase in pediatric asthma emergency room presentation rate per 20 ppb increase in ambient ozone concentration was observed (p-value = 0.001). Ambient ozone level represents a general indicator of air quality due to its correlation with other pollutants. The use of spatially-resolved ozone estimates in the epidemiologic analysis demonstrates the need to control confounding by demographic covariates.

  1. Ozone and other air pollutants from photocopying machines

    SciTech Connect

    Hansen, T.B.; Andersen, B.

    1986-10-01

    The ozone emission from 69 different photocopying machines was determined by a described standard procedure. The emission rates were in the range of 0 to 1350 ..mu..g/min. The concentration in the breathing zone of 19 operators was found to be between less than or equal to 0.001 and 0.15 ppm. Technical conditions for the amount of ozone generated by photocopiers are described, as well as conditions for the rate of decomposition of ozone. The efficiencies of three different types of ozone filters were tested: activated carbon granulate; polyester; and polyurethane impregnated with activated carbon. Other pollutants levels from the copying process (selenium and cadmium) were less than the limit of detection. Dust concentrations (toner) in the air exhausted from photocopies were found in the same magnitude as normal dust concentrations in offices. Vapors from the resin in the toner were often present in concentrations and gave operators an unpleasant feeling.

  2. Approach to forecasting daily maximum ozone levels in St. Louis

    NASA Technical Reports Server (NTRS)

    Prior, E. J.; Schiess, J. R.; Mcdougal, D. S.

    1981-01-01

    Measurements taken in 1976 from the St. Louis Regional Air Pollution Study (RAPS) data base, conducted by EPA, were analyzed to determine an optimum set of air-quality and meteorological variables for predicting maximum ozone levels for each day in 1976. A 'leaps and bounds' regression analysis was used to identify the best subset of variables. Three particular variables, the 9 a.m. ozone level, the forecasted maximum temperature, and the 6-9 a.m. averaged wind speed, have useful forecasting utility. The trajectory history of air masses entering St. Louis was studied, and it was concluded that transport-related variables contribute to the appearance of very high ozone levels. The final empirical forecast model predicts the daily maximum ozone over 341 days with a standard deviation of 11 ppb, which approaches the estimated error.

  3. Winter rain and summer ozone: a predictive relationship.

    PubMed

    Sandberg, J S; Basso, M J; Okin, B A

    1978-06-01

    Insights from dendrochronology have provided a new seasonal predictor for air pollution meteorology. In the San Francisco Bay Area summer ozone excesses over the federal ozone standard are correlated (correlation coefficient r = .87) with precipitation for the two preceding winters, a factor related to tree-ring width in a precipitation-stressed climate. The hypothesis that reactive hydrocarbon emissions from vegetative biomass affects these ozone excesses was supported by a similar correlation between summer hydrocarbon average maximums and the two-winter precipitation factor, reaching r = .88 at suburban stations. A weak tendency for hot summers to follow wet winters (in 16 years of California data) explains only a minor part of the ozone-rain relationship in multiple correlations. PMID:17740697

  4. Interpretation of tropospheric ozone variability in data with different vertical and temporal resolution

    NASA Astrophysics Data System (ADS)

    Petropavlovskikh, I. V.; Disterhoft, P.; Johnson, B. J.; Rieder, H. E.; Manney, G. L.; Daffer, W.

    2012-12-01

    This work attributes tropospheric ozone variability derived from the ground-based Dobson and Brewer Umkehr measurements and from ozone sonde data to local sources and transport. It assesses capability and limitations in both types of measurements that are often used to analyze long- and short-term variability in tropospheric ozone time series. We will address the natural and instrument-related contribution to the variability found in both Umkehr and sonde data. Validation of Umkehr methods is often done by intercomparisons against independent ozone measuring techniques such as ozone sounding. We will use ozone-sounding in its original and AK-smoothed vertical profiles for assessment of ozone inter-annual variability over Boulder, CO. We will discuss possible reasons for differences between different ozone measuring techniques and its effects on the derived ozone trends. Next to standard evaluation techniques we utilize a STL-decomposition method to address temporal variability and trends in the Boulder Umkehr data. Further, we apply a statistical modeling approach to the ozone data set to attribute ozone variability to individual driving forces associated with natural and anthropogenic causes. To this aim we follow earlier work applying a backward selection method (i.e., a stepwise elimination procedure out of a set of total 44 explanatory variables) to determine those explanatory variables which contribute most significantly to the observed variability. We will present also some results associated with completeness (sampling rate) of the existing data sets. We will also use MERRA (Modern-Era Retrospective analysis for Research and Applications) re-analysis results selected for Boulder location as a transfer function in understanding of the effects that the temporal sampling and vertical resolution bring into trend and ozone variability analysis. Analyzing intra-annual variability in ozone measurements over Boulder, CO, in relation to the upper tropospheric

  5. 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)

  6. 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.

  7. Ozone and temperature trends

    NASA Technical Reports Server (NTRS)

    Labitzke, K.; Miller, A. J.; Angell, J.; Deluisi, J.; Frederick, J.; Logan, J.; Mateer, C.; Naujokat, B.; Reinsel, G.; Tiao, G.

    1985-01-01

    The measurement of temporal changes in ozone and temperature are discussed. The data are examined within the context of natural atmospheric variability and data problems. The results are compared to numerical model calculations. The major issues are defined in terms of goal achievement. Each parameter is considered in terms of instrument type, long term effects, and altitude.

  8. 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.

  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. 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.

  11. Revisiting Antarctic Ozone Depletion

    NASA Astrophysics Data System (ADS)

    Grooß, Jens-Uwe; Tritscher, Ines; Müller, Rolf

    2015-04-01

    Antarctic ozone depletion is known for almost three decades and it has been well settled that it is caused by chlorine catalysed ozone depletion inside the polar vortex. However, there are still some details, which need to be clarified. In particular, there is a current debate on the relative importance of liquid aerosol and crystalline NAT and ice particles for chlorine activation. Particles have a threefold impact on polar chlorine chemistry, temporary removal of HNO3 from the gas-phase (uptake), permanent removal of HNO3 from the atmosphere (denitrification), and chlorine activation through heterogeneous reactions. We have performed simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) employing a recently developed algorithm for saturation-dependent NAT nucleation for the Antarctic winters 2011 and 2012. The simulation results are compared with different satellite observations. With the help of these simulations, we investigate the role of the different processes responsible for chlorine activation and ozone depletion. Especially the sensitivity with respect to the particle type has been investigated. If temperatures are artificially forced to only allow cold binary liquid aerosol, the simulation still shows significant chlorine activation and ozone depletion. The results of the 3-D Chemical Transport Model CLaMS simulations differ from purely Lagrangian longtime trajectory box model simulations which indicates the importance of mixing processes.

  12. Updated ozone absorption cross section will reduce air quality compliance

    NASA Astrophysics Data System (ADS)

    Sofen, E. D.; Evans, M. J.; Lewis, A. C.

    2015-12-01

    Photometric ozone measurements rely upon an accurate value of the ozone absorption cross section at 253.65 nm. This has recently been re-evaluated by Viallon et al. (2015) as 1.8 % smaller than the accepted value (Hearn, 1961) used for the preceding 50 years. Thus, ozone measurements that applied the older cross section systematically underestimate the amount of ozone in air. We correct the reported historical surface data from North America and Europe and find that this modest change in cross section has a significant impact on the number of locations that are out of compliance with air quality regulations if the air quality standards remain the same. We find 18, 23, and 20 % increases in the number of sites that are out of compliance with current US, Canadian, and European ozone air quality health standards for the year 2012. Should the new cross-section value be applied, it would impact attainment of air quality standards and compliance with relevant clean air acts, unless the air quality target values themselves were also changed proportionately. We draw attention to how a small change in gas metrology has a global impact on attainment and compliance with legal air quality standards. We suggest that further laboratory work to evaluate the new cross section is needed and suggest three possible technical and policy responses should the new cross section be adopted.

  13. Updated ozone absorption cross section will reduce air quality compliance

    NASA Astrophysics Data System (ADS)

    Sofen, E. D.; Evans, M. J.; Lewis, A. C.

    2015-07-01

    Photometric ozone measurements rely upon an accurate value of the ozone absorption cross section at 253.65 nm. This has recently been reevaluated by Viallon et al. (2015) as 1.8 % smaller than the accepted value (Hearn, 1961) used for the preceding fifty years. Thus, ozone measurements that applied the older cross section systematically underestimate the amount of ozone in air. We correct the reported historical surface data from North America and Europe and find that this modest change in cross section has a significant impact on the number of locations that are out of compliance with air quality regulations if the air quality standards remain the same. We find 18, 23, and 20 % increases in the number of sites that are out of compliance with current US, Canadian, and European ozone air quality health standards for the year 2012. Should the new cross section value be applied, it would impact attainment of air quality standards and compliance with relevant clean air acts, unless the air quality target values themselves were also changed proportionately. We draw attention to how a small change in gas metrology has a global impact on attainment and compliance with legal air quality standards. We suggest that further laboratory work to evaluate the new cross section is needed and suggest three possible technical and policy responses should the new cross section be adopted.

  14. 77 FR 37812 - Approval and Promulgation of Air Quality Implementation Plans; South Carolina; Emissions Statements

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-25

    ... standard on March 27, 2008 (73 FR 16436). Today's action, however, relates to the 1997 ozone standard. The...-existing 1-hour ozone standard was promulgated (62 FR 38856), the risks associated with exposure to lower... designations and classifications for the revised 1997 8-hour ozone standard (69 FR 23858). These actions...

  15. 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

  16. 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

  17. Validation of OMI total ozone retrievals from the SAO ozone profile algorithm and three operational algorithms with Brewer measurements

    NASA Astrophysics Data System (ADS)

    Bak, J.; Liu, X.; Kim, J. H.; Chance, K.; Haffner, D. P.

    2015-01-01

    The accuracy of total ozone computed from the Smithsonian Astrophysical Observatory (SAO) optimal estimation (OE) ozone profile algorithm (SOE) applied to the Ozone Monitoring Instrument (OMI) is assessed through comparisons with ground-based Brewer spectrometer measurements from 2005 to 2008. We also compare the three OMI operational ozone products, derived from the NASA Total Ozone Mapping Spectrometer (TOMS) algorithm, the KNMI (Royal Netherlands Meteorological Institute) differential optical absorption spectroscopy (DOAS) algorithm, and KNMI's Optimal Estimation (KOE) algorithm. The best agreement is observed between SAO and Brewer, with a mean difference of within 1% at most individual stations. The KNMI OE algorithm systematically overestimates Brewer total ozone by 2% at low and mid-latitudes and 5% at high latitudes while the TOMS and DOAS algorithms underestimate it by ~1.65% on average. Standard deviations of ~1.8% are calculated for both SOE and TOMS, but DOAS and KOE have higher values of 2.2% and 2.6%, respectively. The stability of the SOE algorithm is found to have insignificant dependence on viewing geometry, cloud parameters, or total ozone column. In comparison, the KOE-Brewer differences are significantly correlated with solar and viewing zenith angles and show significant deviations depending on cloud parameters and total ozone amount. The TOMS algorithm exhibits similar stability to SOE with respect to viewing geometry and total column ozone, but has stronger cloud parameter dependence. The dependence of DOAS on observational geometry and geophysical conditions is marginal compared to KOE, but is distinct compared to the SOE and TOMS algorithms. Comparisons of all four OMI products with Brewer show no apparent long-term drift, but seasonal features are evident, especially for KOE and TOMS. The substantial differences in the KOE vs. SOE algorithm performance cannot be sufficiently explained by the use of soft calibration (in SOE) and the use of

  18. Bias in Dobson total ozone measurements at high latitudes due to approximations in calculations of ozone absorption coefficients and air mass

    NASA Astrophysics Data System (ADS)

    Bernhard, G.; Evans, R. D.; Labow, G. J.; Oltmans, S. J.

    2005-05-01

    The Dobson spectrophotometer is the primary standard instrument for ground-based measurements of total column ozone. The accuracy of its data depends on the knowledge of ozone absorption coefficients used for data reduction. We document an error in the calculations that led to the set of absorption coefficients currently recommended by the World Meteorological Organisation (WMO). This error has little effect because an empirical adjustment was applied to the original calculations before the coefficients were adopted by WMO. We provide evidence that this adjustment was physically sound. The coefficients recommended by WMO are applied in the Dobson network without correction for the temperature dependence of the ozone absorption cross sections. On the basis of data measured by Dobson numbers 80 and 82, which were operated by the National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory at the South Pole, we find that omission of temperature corrections may lead to systematic errors in Dobson ozone data of up to 4%. The standard Dobson ozone retrieval method further assumes that the ozone layer is located at a fixed height. This approximation leads to errors in air mass calculations, which are particularly relevant at high latitudes where ozone measurements are performed at large solar zenith angles (SZA). At the South Pole, systematic errors caused by this approximation may exceed 2% for SZAs larger than 80°. The bias is largest when the vertical ozone distribution is distorted by the "ozone hole" and may lead to underestimation of total ozone by 4% at SZA = 85° (air mass 9). Dobson measurements at the South Pole were compared with ozone data from a collocated SUV-100 UV spectroradiometer and Version 8 overpass data from NASA's Total Ozone Mapping Spectrometer (TOMS). Uncorrected Dobson ozone values tend to be lower than data from the two other instruments when total ozone is below 170 Dobson units or SZAs are larger than

  19. 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.

  20. 40 CFR 52.2037 - Control strategy plans for attainment and rate-of-progress: Ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hour ozone standard of 40 CFR 50.9: the attainment demonstration and reasonably available control... affecting § 52.2037, see the List of CFR Sections Affected, which appears in the Finding Aids section of the... and rate-of-progress: Ozone. 52.2037 Section 52.2037 Protection of Environment...

  1. 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... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Virginia § 52.2428... Progress Plan for the Virginia portion of the Metropolitan Washington, D.C. ozone nonattainment...

  2. 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... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Virginia § 52.2428... Progress Plan for the Virginia portion of the Metropolitan Washington, D.C. ozone nonattainment...

  3. 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... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control Strategy: Carbon monoxide and... Control Strategy: Carbon monoxide and ozone. (a) Determination—EPA has determined that, as of November...

  4. AIR QUALITY CRITERIA FOR OZONE AND RELATED PHOTOCHEMICAL OXIDANTS VOLUME I OF III (Final, 1996)

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) promulgates the National Ambient Air Quality Standards (NAAQS) on the basis of scientific information contained in air quality criteria documents. The previous ozone (O3) criteria document, Air Quality Criteria for Ozone and Other Ph...

  5. 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...

  6. 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...

  7. 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. PMID:9519506

  8. 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.

  9. [Correlation Analysis Between Characteristics of VOCs and Ozone Formation Potential in Summer in Nanjing Urban District].

    PubMed

    Yang, Xiao-xiao; Tang, Li-li; Zhang, Yun-jiang; Mu, Ying-feng; Wang, Ming; Chen, Wen-tai; Zhou, Hong-cang; Hua, Yan; Jiang, Rong-xin

    2016-02-15

    Volatile organic compounds (VOCs) is an important precursor of photochemical ozone pollution (O3) in the atmosphere. Their concentration variation directly affects the characteristics of the ozone pollution. The concentration, speciation of VOCs, ozone and its precursors in Nanjing were analyzed and measured using online gas detection systems in August 2013. VOCs/NOx discriminant method was used to get the sensitive control factors of ozone. The results showed that the averaged volume fraction of VOCs was 52. 05 x 10(-9), and the largest one reached 200 x 10(-9) in Nanjing urban district. The order of volume fraction of each species VOCs was alkane > oxygen-containing VOCs > alkene > aromatics. The averaged concentration of ozone was 76.5 microg x m(-1) and the exceeding concentration of hourly standard was 5.9%. The change trends of ozone precursors VOCs and NOx were basically identical and Ozone showed the obvious negative correlation during the period of high concentrations of ozone. There were some differences in the concentrations of the same VOCs in different ozone concentration periods. The ozone generation in Nanjing urban district was sensitive to VOCs, and Nanjing belonged to VOCs control area in summer. PMID:27363129

  10. [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

  11. Ozone climatology of the Dallas-Fort Worth area and its relationship to meteorology

    SciTech Connect

    Nobis, T.E.

    1998-10-26

    The Environmental Protection Agency has established a National Ambient Air Quality Standard for surface ozone through the Clean Air Act and its amendments. The Dallas/Fort Worth area is in violation of these standards, and to date, no extensive studies on ozone in this area have been published. This study presents a broad overview of the ozone problem in the DFW area. Ozone-meteorology relationships were examined using scatterplots and correlation coefficients. Most of the meteorology variables only displayed a rate-limiting role with ozone. Correlation values displayed significant seasonal variation, with temperature having a much lower correlation than expected based on results from other studies. Conditional Climatology Tables were constructed to explore which combination of variables pointed to the highest ozone days. Yesterday`s ozone, wind speed, and wind direction were found the most predictive. In general, low wind speeds and wind directions from the E-SE were most favorable for high ozone. Wind direction biases were examined using windroses and by examining upwind vs. downwind behavior at the periphery sites. Evidence suggests that high ozone in the east, south, and west has occurred, but has gone undetected due to a lack of consistent monitoring there. There is also some evidence that winds from the E-SE may be transporting precursors from outside the DFW area, although further research is required.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. 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

  17. The Antarctic ozone hole

    SciTech Connect

    Stolarski, R.S.

    1988-01-01

    Because the effects are so serious, many investigators have been racing to determine the causes of the hole which develops each southern spring within the polar vortex, an isolated air mass that circulates around the South Pole during a large part of the year. This paper reviews two of the foremost theories for this ozone hole. Mechanisms of the pollution theory, which proposes that the cause is chlorofluorocarbons and nitrogen oxides in the atmosphere, are reviewed. The second theory proposes a natural shift in the air movements that transport ozone-rich air into the polar stratosphere during the southern spring as the cause. Current data suggest both theories are correct, but data are considered inconclusive.

  18. Evaluation of ACCMIP Outgoing Longwave Radiation from Tropospheric Ozone Using TES Satellite Observations.

    NASA Technical Reports Server (NTRS)

    Bowman, Kevin W.; Shindell, Drew Todd; Worden, H. M.; Lamarque, J. F.; Young, P. J.; Stevenson, D. S.; Qu, Z.; delaTorre, M.; Bergmann, D.; Cameron-Smith, P. J.; Collins, W. J.; Doherty, R.; Dalsoren, S. B.; Faluvegi, G.; Folberth, G.; Horowitz, L. W.; Josse, B. M.; Lee, Y. H.; MacKenzie, I. A.; Myhre, G.; Nagashima, T.; Naik, V.; Strode, S. A.; Kulawik, S. S..; Worden, J. R.

    2013-01-01

    We use simultaneous observations of tropospheric ozone and outgoing longwave radiation (OLR) sensitivity to tropospheric ozone from the Tropospheric Emission Spectrometer (TES) to evaluate model tropospheric ozone and its effect on OLR simulated by a suite of chemistry-climate models that participated in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). The ensemble mean of ACCMIP models show a persistent but modest tropospheric ozone low bias (5-20 ppb) in the Southern Hemisphere (SH) and modest high bias (5-10 ppb) in the Northern Hemisphere (NH) relative to TES ozone for 2005-2010. These ozone biases have a significant impact on the OLR. Using TES instantaneous radiative kernels (IRK), we show that the ACCMIP ensemble mean tropospheric ozone low bias leads up to 120mW/ sq. m OLR high bias locally but zonally compensating errors reduce the global OLR high bias to 39+/- 41mW/ sq. m relative to TES data. We show that there is a correlation (Sq. R = 0.59) between the magnitude of the ACCMIP OLR bias and the deviation of the ACCMIP preindustrial to present day (1750-2010) ozone radiative forcing (RF) from the ensemble ozone RF mean. However, this correlation is driven primarily by models whose absolute OLR bias from tropospheric ozone exceeds 100mW/ sq. m. Removing these models leads to a mean ozone radiative forcing of 394+/- 42mW/ sq. m. The mean is about the same and the standard deviation is about 30% lower than an ensemble ozone RF of 384 +/- 60mW/ sq. m derived from 14 of the 16 ACCMIP models reported in a companion ACCMIP study. These results point towards a profitable direction of combining satellite observations and chemistry-climate model simulations to reduce uncertainty in ozone radiative forcing.

  19. Determination of oxidant exposure during ozonation of secondary effluent to predict contaminant removal.

    PubMed

    Zucker, Ines; Avisar, Dror; Mamane, Hadas; Jekel, Martin; Hübner, Uwe

    2016-09-01

    The use of kinetic models to predict oxidation performance in wastewater is limited due to fast ozone depletion during the first milliseconds of the reaction. This paper introduces the Quench Flow Module (QFM), a bench-scale experimental technique developed to measure the first 5-500 milliseconds of ozone depletion for accurate determination of ozone exposure in wastewater-ozonation processes. Calculated ozone exposure in QFM experiments was up to 24% lower than in standard batch experiments, strongly depending on the initial sampling point for measurement in batch experiments. However, oxidation rates of slowly- and moderately-reacting trace organic compounds (TrOCs) were accurately predicted from batch experiments based on integration of ozone depletion and removal of an ozone-resistant probe compound to calculate oxidant exposures. An alternative concept, where ozone and hydroxyl radical exposures are back-calculated from the removal of two probe compounds, was tested as well. Although the QFM was suggested to be an efficient mixing reactor, ozone exposure ranged over three orders of magnitude when different probe compounds reacting moderately with ozone were used for the calculation. These effects were beyond uncertainty ranges for apparent second order rate constants and consistently observed with different ozone-injection techniques, i.e. QFM, batch experiments, bubble columns and venturi injection. This indicates that previously suggested mixing effects are not responsible for the difference and other still unknown factors might be relevant. Results furthermore suggest that ozone exposure calculations from the relative residual concentration of a probe compound are not a promising option for evaluation of ozonation of secondary effluents. PMID:27232995

  20. 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

  1. 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 ( ...

  2. Ozonated olive oils and the troubles

    PubMed Central

    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

  3. 77 FR 67600 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-13

    ....08 parts per million (ppm) oxidant to an hourly average of 0.12 ppm ozone. See 44 FR 8202 (February 8... the 1-hour ozone NAAQS. See 51 FR 41788 (November 19, 1986). In 1997, EPA revised the NAAQS for ozone... (77 FR 30088). This rulemaking relates only to the 1997 8-hour ozone standard and does not relate...

  4. 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%.

  5. 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.

  6. Another deep Antarctic ozone hole

    SciTech Connect

    Kerr, R.A.

    1990-10-19

    Again in 1990, drastic depletion of stratospheric ozone over the South Pole has been measured, in August 140 Dobson units, far below the 220 Dobson units typically seen over Antarctica. This extensive destruction of ozone is determined to be brought about by sunshine acting in combination with the chlorine released from chlorofluorohydrocarbons (CFCs) by icy stratospheric clouds. It is concluded that CFC concentrations have now reached a level that will almost totally destroy the ozone in the lower stratosphere in most years.

  7. 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.

  8. Effect of ozone on respiratory responses in subjects with asthma

    SciTech Connect

    Koenig, J.Q.

    1995-03-01

    In the process of understanding the respiratory effects of individual air pollutants, it is useful to consider which populations seem to be most susceptible to the exposures. Ozone is the most ubiquitous air pollutant in the United States, and there is great interest in the extent of susceptibility to this air pollutant. This review presents evidence that individuals with asthma are more susceptible to adverse respiratory effects from ozone exposure than are nonasthmatic individuals under similar circumstances. In studies comparing patients with asthma to nonasthmatic subjects, research has shown increased pulmonary-function decrements, an increased frequency of bronchial hyperresponsiveness in ozone responders, increased signs of upper airway inflammation after ozone exposure, and an increased response to inhaled sulfur dioxide or allergen in the subjects with asthma. Subjects with asthma are indeed a population susceptible to the inhaled effects of ozone. These data need to be considered by regulators who are charged with setting air quality standards to protect even the most susceptible members of the population. They also underline the importance of strategies to reduce human exposure to ambient ozone. 16 refs., 1 fig.

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. Table Mountain ozone intercomparison: Brewer ozone spectrophotometer Umkehr observations

    SciTech Connect

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

    1995-05-20

    The authors present the result of ozone column measurements, and vertical profiles, derived from Brewer ozone spectrophotometer measurements, in conjunction with the Umkehr technique. The Umkehr results agreed within 15% with the average measurments of this campaign between 20 and 40 km altitude. When restricted to the altitude range of 24 to 40 km the agreement was within about 5%.

  14. 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

  15. 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.

  16. 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.

  17. Validation of OMI Total Ozone Retrievals from the SAO Ozone Profile Algorithm and Three Operational Algorithms 3 with Brewer Measurements

    NASA Astrophysics Data System (ADS)

    Bak, Juseon; Kim, Jae H.; Liu, Xiong; Chance, Kelly

    2015-04-01

    The optimal estimation (OE) based ozone profile algorithm developed at Smithsonian 3 Astrophysical Observatory (SAO) is assessed as to its accuracy to extract total ozone amount from 4 Ozone Monitoring Instrument (OMI) measurements through the validation using Brewer ground 5 based measurements between January 2005 and December 2008. We compare it against the quality of 6 three OMI operational ozone products, derived from NASA TOMS, KNMI DOAS, and KNMI OE 7 algorithms, respectively. The validation demonstrates that the SAO ozone profile algorithm generally 8 has the best total ozone retrieval performance compared to the three OMI operational ozone products. 9 The individual station comparisons show an agreement between SAO and Brewer within ± 1% except 10 at polar stations (~ -2 %), with a high correlation coefficient of ~ 0.99 at most stations. The KNMI OE 11 algorithm systematically overestimates the true total ozone value at all stations with a bias from 2 % 12 at low/mid latitude stations to 5 % at high latitude stations. On the other hand, TOMS/DOAS 13 algorithm underestimates total ozone by ~ -1.7 % on average. The standard deviations of differences 14 are ~ 1.8 % for SAO and TOMS while DOAS and KNMI show the standard deviation values of 2.2 15 and 2.5 %, respectively. The remarkable stability of SAO OE algorithm is found with no significant 16 dependency on algorithmic variables such as viewing geometries, cloud parameters, and time. In 17 comparison, the severe dependency on both solar and viewing zenith angles is found in KNMI OE 18 algorithm, which is characterized with a negative (positive) correlation with smaller (larger) solar 19 zenith angles and the strong cross-track dependent biases ranging from 4% at nadir and 1% at off-20 nadir positions. The dependence of DOAS and TOMS algorithms on the algorithmic variables is 21 marginal compared to KNMI OE algorithm, but distinct compared to SAO OE algorithm. Relative 22 differences between SAO/DOAS and

  18. 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

  19. Equatorial ozone profiles from the ground to 52 km during the Southern Hemisphere autumn

    NASA Technical Reports Server (NTRS)

    Barnes, Robert A.; Holland, Alfred C.; Kirchhoff, Volker W. J. H.

    1987-01-01

    The results of an ozone measurement campaign conducted at Natal, Brazil from March 25 to April 15, 1985 are reported. Complete profiles of ozone, pressure, and temperature were obtained from the ground to 52 km, and all of the profiles correspond with site overpasses by ozone instruments on NASA and NOAA satellites. The profiles from this measurement series show reasonable agreement with established satellite climatologies. Stratospheric ozone variability was 2 percent or less during the 3 weeks of the measurement campaign, with stratospheric temperature and pressure variabilities half that amount. Low variability at a single location for this period implies comparable uniformity for ozone profiles over a large area around the measurement site. The auxiliary pressure and temperature profiles presented here allow the use of this data set as a transfer standard between satellite instruments with different fundamental ozone measurements. Finally, the low ozone variability in the stratosphere at Natal during this measurement series should provide an opportunity for high-quality intercomparisons of measured and modeled ozone concentrations in the equatorial stratosphere and lower mesosphere as well as a consistency check among satellite ozone measurements.

  20. Ozone profile measurements at McMurdo Station Antarctica during the spring of 1987

    NASA Technical Reports Server (NTRS)

    Hofmann, D. J.; Harder, J. W.; Rosen, J. M.; Hereford, J.; Carpenter, J. R.

    1988-01-01

    During the Antarctic spring of 1986, 33 ozone soundings were conducted from McMurdo Station. These data indicated that the springtime decrease in ozone occurred rapidly between the altitudes of 12 and 20 km. During 1987, these measurements were repeated with 50 soundings between 29 August and 9 November. Digital conversions of standard electrochemical cell ozonesondes were again employed. The ozonesonde pumps were individually calibrated for flow rate as the high altitude performance of these pumps have been in question. While these uncertainties are not large in the region of the ozone hole, they are significant at high altitude and apparently resulted in an underestimate of total ozone of about 7 percent (average) as compared to the Total Ozone Mapping Spectrometer (TOMS) in 1986, when the flow rate recommended by the manufacturer was used. At the upper altitudes (approx. 30 km) the flow rate may be overestimated by as much as 15 percent using recommended values (see Harder et al., The UW Digital Ozonesonde: Characteristics and Flow Rate Calibration, poster paper, this workshop). These upper level values are used in the extrapolation, at constant mixing ratio, required to complete the sounding for total ozone. The first sounding was on 29 August, prior to major ozone depletion, when 274 DU total ozone (25 DU extrapolated) was observed. By early October total ozone had decreased to the 150 DU range; it then increased during mid-October owing to motion of the vortex and returned to a value of 148 DU (29 DU extrapolated) on 27 October.