1 / 13

First Stage of Recovery in the Stratospheric Ozone Layer

First Stage of Recovery in the Stratospheric Ozone Layer. AGU Spring Meeting 23-27 May 2005 New Orleans, LA. Eun-Su Yang/Ga Tech Derek M. Cunnold/Ga Tech Ross J. Salawitch/JPL M. Patrick McCormick/Hampton U James Russell III/Hampton U Joseph M. Zawodny/LaRC Samuel Oltmans/CMDL

alma
Download Presentation

First Stage of Recovery in the Stratospheric Ozone Layer

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. First Stage of Recovery in the Stratospheric Ozone Layer AGU Spring Meeting 23-27 May 2005 New Orleans, LA Eun-Su Yang/Ga Tech Derek M. Cunnold/Ga Tech Ross J. Salawitch/JPL M. Patrick McCormick/Hampton U James Russell III/Hampton U Joseph M. Zawodny/LaRC Samuel Oltmans/CMDL Michael J. Newchurch/UAH 1

  2. Equivalent Effective Stratospheric Chlorine EESC peak in ~1997. Timing adjusted for transport to the stratosphere in WMO [2003] .

  3. Fractional Ozone loss calculated in PC model. Peak loss during Pinatubo, as expected. Larger losses at higher latitudes. Consistent with loss expected from EESC record.

  4. Residual ozone columnfrom SAGE and HALOEabove 18km60S-60N[O3]t =  + t + [Seasonal terms] + [QBO terms] + γ [F10.7]t + a1Nt-1 + t Cumulative sum of SAGE residual, ,, departures from projected trend line 1997-2005. 2-Sigma envelope (dotted). Constant level (green).

  5. Residualtotalozone columnfrom Dobson/Brewer 30S-60N (top)andmerged TOMS/SBUV 60S-60N (bottom).

  6. Cumulative sum total ozone column Dobson/Brewer 30S-60N (top) and Merged TOMS/SBUV 60S-60N (bottom) residuals from projected trend line 1997-2005. Total columns recover more than 18 km-TOA due to gains between tropopause – 18 km.

  7. SAGE/HALOE (black) stratospheric ozone column (TP+2km to TOA) 60S-70S Temperature effects removed, and saturation effect shown to be negligible north of 70S (not negligible at 90S). Also shows clear chlorine signature (red) ~1997 inflection and slight increasing afterward [Yang et al., accepted, GRL, 2005]

  8. Middle stratospheric ozone data from SAGE (pre 91) and HALOE (post 93) in black. EESC regression onto ozone (blue). Ozone expected from observationally constrained PC model calculations (red). Consistent results. Time series (top) CUSUMs (bottom)

  9. Middle stratospheric ozone data from ozonesondes 18-25 km agree with SAGE/HALOE and EESC regression. Time series (top) CUSUMs (bottom)

  10. EESC influence on Middle stratosphere: strong EESC influence on Lower Stratosphere: moderate

  11. PV influence on Middle Stratosphere: noneSimilar for Tropopause Height PV influence on Lower Stratosphere: moderate Similar for Tropopause Height Tropopause – 18 km 18-25 km

  12. CONCLUSIONS The decline in the global stratospheric ozone layer has stopped. 3 independent satellite sensors: SAGE, HALOE, merged TOMS/SBUV and 2 ground networks: Dobson/Brewer and ozonesondes, all show consistent results in ozone trends and recovery signatures. Most (81%) of the ozone loss occurred above 18 km. Half of the recovery occurred tropopause-18km. Chlorine signature expected from the Montreal Protocol and Amendments is clear in ozone improvement in the middle and upper stratosphere. Dynamics, not chlorine, controls ozone behavior in lower stratosphere. Climate change interactions and potential stratospheric aerosol injections will influence the ozone recovery signature.

  13. http://nsstc.uah.edu/atmchem/ Acknowledgements WOUDC NASA/ESE NOAA/NGDC Swiss Met Service Steve Montzka/CMDL NASA/LaRC data center NASA/GSFC data center International ozonesonde programs This work is dedicated to the memory of Professor Greg Reinsel

More Related