Charles Jackman October 9, 2012

Transcription

1 Overview of Energetic Particle Precipitation (EPP) Effects on the Earth's Atmosphere Charles Jackman NASA Goddard Space Flight Center, Greenbelt, MD October 9, 2012

2 Acknowledgments: Cora Randall University of Colorado, Boulder, CO Daniel Marsh, Francis Vitt, and Rolando Garcia National Center for Atmospheric Research, Boulder, CO Eric Fleming NASA Goddard Space Flight Center, Greenbelt, MD Shuhui h Wang JPL, California Institute of Technology, Pasadena, CA Pekka Verronen Finnish Meteorological Institute, Helsinki, FINLAND Bernd Funke Instituto de Astrofisica de Andalucia, CSIC, Granada, SPAIN

3 Outline I. Introduction II. EPP-caused HO x and Ozone Change III. EPP-caused NO x, NOy, and Ozone Change IV. Conclusions

4 I. Introduction Ultimate t origin i of most Energetic Particles is the Sun Galactic Cosmic Rays (GCRs) originate outside the Solar System and will not be discussed

5 I. Introduction Ultimate t origin i of most Energetic Particles is the Sun Galactic Stay Cosmic tuned Rays (GCRs) for Jón-Egill Kristjánsson stalk originate outside the Solar System and at will 11:10 not Tomorrow be discussed about GCR impacts

6 Overview of Energetic Particle Precipitation Electrons and Protons comprise most (~90% or so) of these Particles Higher flux of particles associated with: 1) Solar flares, 2) Coronal mass ejections (CMEs), 3) Geomagnetic storms

7 Animation of Coronal Mass Ejection

8

9 Electron Precipitation Lower energy Auroral electrons auroral zone [~62-75 o geomag. lat.] 60 o 50 o 40 o 70 o 80 o 90 o N geomagnetic Medium & high energy electrons subauroral zone [~55-65 o geom. lat.] Each zone is ~9% of Earth area.

10 Protons also come via CMEs and enter through the magnetosphere near the poles and precipitate there Earth Solar Proton Event (SPE) Sun GOES GOES - Geostationary Operational Environmental Satellites

11 Proton Precipitation Solar protons 40 o 50 o Polar Caps >~60 80 o o geomag. 90o N geomagnetic lat. 60 o 70o Very intense solar events push polar cap boundaries Equatorward About 14% of Earth is affected during solar proton events.

12 125 Thermosphere 100 Mesopause Altit tude (km m) Middle Atmosphere Mesosphere Stratosphere Stratopause 0 Troposphere Tropopause Atmospheric Structure

13 kev electron 1 kev electron Thermosphere 1 MeV proton Altit tude (km m) MeV electron kev electron Middle Atmosphere Bremsstrahlung penetrate further Mesosphere Stratosphere Troposphere Mesopause 10 MeV proton Stratopause 100 MeV proton Tropopause Atmospheric Structure

14 Atmospheric Influences of Energetic Particle Precipitation Most (70-80%) of the Energy Deposited creates Ion Pairs: free Electron & positive Ion

15 Energetic Particle Precipitation Medium & High Energy Electrons Solar Protons

16 What are the dates of some large Solar Proton Events?

17 Largest 15 Solar Proton Events (SPEs) in Past 50 Years Date of SPEs Computed Rank (Total Ion Pair Production) October August July October 28-31, Note that seven November 5-7, of the largest SPEs November occurred in ! September August November 23-25, March Note that two September of the largest SPEs January occurred in 2012! January Sep. 29 Oct. 3, Jan. 28 Feb. 1,

18 -1 Large SPE GOES Proton Flux Data Note the large (>100X) enhancement! 10 4 Par rticles cm -2 s -1 sr (March 6-11, 2012) >10MeV Day in March 2012

19 Ionization Rates (#cm -3 s -1 ) March 6-11, Mesosphere Stratosphere Day in March Protons from MeV included d Contour levels: 100, 200, 500, 1000, & 2000 (#cm -3 s -1 )

20 Energetic Particles also Produce HO x (H,OH,HO 2 ) & NO x (N,NO,NO 2 ) Both of which can destroy Ozone

21 II. EPP-caused HO x and Ozone Change

22 EPPs Enhance HO x (H, OH, HO 2 ) HO x constituents are produced through water cluster ion formation & neutralization Primarily short-term effects as HO x lifetime is short (~hours) in the atmosphere HO x production by EPPs to be shown here: For Solar Proton Event in March 2012 For Electron Precipitation in April 2006

23 Solar Proton HO x Production

24 Ionization Rates (top) & HO x Production Rates (bottom) for March 6-11, Day in March 2012 Contour levels: 100, 200, 500, 1000, 2000, & 5000 (#cm -3 s -1 )

25 Aura MLS (Microwave Limb Sounder) measures HO 2 and Ozone

26 HO MLS and 2D Model HO 2 Polar NH ( o ) 2 (ppbv) change for o N Latitude Band March 6-11, HO 2 average for Feb.14-Mar.5 (3 weeks) is subtracted from Mar values Day in March Top: MLS Data Bottom: Computed HO x Production 100

27 Ozone Impact March 2012 SPE Aura MLS observations

28 MLS and 2D Model Ozone Polar NH ( o ) March 6-11, 2012 Ozone(%) & HO change for o 2 change for N Latitude o N Lat. Band Average for Feb.14-Mar.5 (3 weeks) is subtracted from Mar values Day in March D Model Top: MLS Ozone Data Bottom: MLS HO 2 Data Day in March 2012

29 OH Production Precipitating Electrons in April 2006 Aura MLS - OH observations Adapted from Verronen et al. [2011]

30 Aura MLS OH Measurements (71-78 km) vs. Medium Energy Electron Flux ( kev) OH co oncentra ation [cm -3 ] x OH on for Jan. geomagnetic 15 (before latitudes SPE) o N Corr. Coef. = 0.93 Larger OH correlated with Higher 12 Electron Flux Electron Count Rate (s -1 ) April 2006 period id Adapted from Verronen et al. [2011]

31 III. EPP-caused NO x, NO y, and Ozone Change

32 EPPs Enhance NO x (N, NO, NO 2 ) NO x constituents are produced by primary electrons and protons and associated secondary electrons dissociating N 2 g 2 Short- and long-term effects as NO x constituents can last for weeks SCISAT-1 ACE (Atmospheric Chemistry Experiment) measures NO x (NO+NO 2 ) constituents t Adapted from Randall et al. [2006]

33 NO x in the Northern Hemisphere (50-85 o N) Use ACE started Feb. 18, No Measurements Stratopause January February March 10 Year 2004: Significant EPP (electrons) in 2004 Also, Unusual Meteorology - Sudden Stratospheric Warming (SSW) in January - Enhanced descent Adapted from Randall et al. [2006]

34 NO x in the Northern Hemisphere (50-85 o N) Use ACE started Feb. 18, No Measurements Stratopause January February March Downward transport of NO x from the Mesosphere to the Upper Stratosphere Year 2004: Significant EPP (electrons) in 2004 Also, Unusual Meteorology - Sudden Stratospheric Warming (SSW) in January - Enhanced descent 10 Adapted from Randall et al. [2006]

35 NO x descent in Northern Hem. Use ACE (50-85 o N) 2004 Years 2004, 2006, 2009: Unusual Meteorology Stratopause descent Stratopause Stratopause January February March Adapted from Randall et al. [2009]

36 NOAlso, x descent note in that: Northern Hem. Use ACE (50-85 o N) Years 2005, 2007, 2008, 2010, & 2011 did not show enhanced descent Years 2004, 2006, 2009: Unusual Meteorology Stratopause descent Stratopause However: Yrs 2006 and 2009 did not show much NO x descent to stratosphere 2009 Stratopause January February March 10 Adapted from Randall et al. [2009]

37 Now back to Year 2004: How did the electron-produced NO x impact Ozone? Use data from POAM (Polar Ozone and Aerosol Measurement) instruments Adapted from Randall et al. (2005)

38 POAM II & III obs. (54-71 o N) NO 2 at 40 km 2 Ozone at 40 km Column Ozone ( km) -1.5 to 3 D.U. (~0.5-1%) Adapted from Randall et al. (2005)

39 POAM II & III obs. (54-71 o N) NO 2 at 40 km 2 Year 2004 appears to be very Ozone at 40 km exceptional for EPP (electron) NO x transport to the Stratosphere Column Ozone ( km) -1.5 to 3 D.U. (~0.5-1%) Adapted from Randall et al. (2005)

40 Does the electron-caused Ozone change impact Climate? Stay tuned for Annika Seppälä stalk at 16:30 Today for more information

41 Largest 15 Solar Proton Events (SPEs) in Past 50 Years Date of SPEs October August July October 28-31, November 5-7, November September August November 23-25, March September January January Sep. 29 Oct. 3, Jan. 28 Feb. 1, Computed Rank (Total Ion Pair Production) Halloween SPE of Oct was Very Large

42 In memory of: ESA Envisat (1 March, April, 2012) Over 10 years of Earth observations MIPAS, SCIAMACHY, & GOMOS Instruments provided great measurements of EPP impact on the Atmosphere

43 MIPAS provided measurements of most NO y constituents: NO, NO 2, N 2 O 5, HNO 3, HO 2 NO 2, ClONO 2 Only missing N, NO 3, BrONO 2, which are minuscule in the middle atmosphere. NOy lifetime can be long (~months)

44 MIPAS NO y (NO+NO 2 +2N 2 O 5 +HNO 3 +ClONO 2 +HNO 4 ) observations (40-90 o N) in Changes with respect 1 to October 26, Adapted from Funke et al. (2011)

45 Model Whole Atmosphere Community Climate Model (WACCM) NCAR Model - Domain [90 o S 90 o Ground to N, km] Lower Thermosphere! - Atmospheric physics & photochemistry - Specified dynamics from measurements for 2003 Perturbed: Simulation With SPEs D. Marsh et al.

46 NO y (40-90o N) in 2003 MIPAS WACCM Changes with respect to October 26, Adapted from Funke et al. (2011)

47 More WACCM Simulations Interactive dynamics Perturbed ( ): Four realizations With SPEs Base ( ): Four realizations Without SPEs Difference mean of Perturbed and Base results to compute SPE-caused change Look at Average for Years

48 Perturbed Base ( average) Very Large SPEs in 2000, 2001, & 2003 From Jackman et al. (2009)

49 Perturbed Base ( average) Colored dregions are Statistically Significant to 95% (Student s t-test) From Jackman et al. (2009)

50 Perturbed Base ( average) Large stratospheric area with statistically significant NO y increase Some stratospheric area with statistically significant Ozone decrease (mainly NH) Ozone decrease more NO y -induced O 3 loss Ozone increase Interference of NO y with Cl/Br O 3 loss Colored dregions are Statistically Significant to 95% (Student s t-test) From Jackman et al. (2009)

51 Do Solar Proton Events impact Total Ozone?

52 Predicted Impact (GSFC 2D Model) of Solar Protons on Total Ozone (%) % Ozone change From Jackman et al. (2008)

53 Predicted Impact (GSFC 2D Model) of Solar Protons on Total Ozone (%) Larger decreases in NH caused by 1989, 2001, & SPEs % Ozone change Larger decreases in SH caused by 1972, 1989, & SPEs From Jackman et al. (2008)

54 Predicted Impact (GSFC 2D Model) of Solar Protons on Total Ozone (%) Computed Larger Total decreases Ozone in decreases NH caused by 1989, 2001, & SPEs % Ozone change from SPEs are <3% These can be compared with measured interannual variability Larger decreases in SH caused by 1972, 1989, & SPEs of up to ~10%, thus are not observable e From Jackman et al. (2008)

55 IV. Conclusions Both electrons & protons influence the polar mesosphere/stratosphere mainly in certain years e.g., near solar max, large Ap, unusual meteorology EPP produces HO x, which is short-lived Mesospheric Ozone depletion can be large (>20%) EPP produces long-lived NOy (1972, 89, 2000, 01, 03, 04, 06?) Stratospheric Ozone impacts can last for months Computed total ozone changes are small (<3%)

56 Addendum: EPP also impacts other constituents (e.g., HNO 3,N 2 O 5,HO 2 NO 2,N 2 OClONO O,ClONO 2, ClO,HOCl,HCl,CO,H 2 O 2 ) & T Thank you for your attention! ti