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This project focuses on modeling the impacts of energetic particles in the atmosphere, including electrons, solar protons, and galactic cosmic rays. It explores ionization rates, chemistry reactions, and the redistribution of atmospheric components. Various models and schemes are employed to understand the complex interactions that influence ozone depletion, nitrogen chemistry, and climate change. The study also delves into the effects of solar activity on ozone levels and surface temperatures, offering insights into potential future scenarios. The research aims to advance our understanding of energetic particle effects and their role in shaping Earth's atmosphere.
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Modeling efforts towards understanding the energetic particle effects in the atmosphere Eugene Rozanov PMOD/WRC, Davos and IAC ETH, Zurich, Switzerland e.rozanov@pmodwrc.ch
Precipitating energetic particles Electrons Low Energy: From plasma-sheat to auroral oval Medium to high Energy: From the Radiation Belts to subauroral areas Solar Protons: polar cap Galactic cosmic rays: From outside to everywhere Vertical distribution depends on particle energy Rodger and Clilverd, Nature, 2008
Processes Transport Ion and neutral chemsitry Ozone chemistry Clouds Micro-physics Atmosphere, Climate Ionization GEC Particle precipitation
Modeling of the ionization rates Input: Observed fluence and energy spectrum, geomagnetic field Method: Energy degradation scheme Jackman et al., 1980; P. Verronen Monte-Carlo models AIMOS, Wissing CRAC:CRII, Usoskin et al., 2010 Output: Ionization rates as a function of Pressure, location, solar activity, date
Modeling of the ionization rates Semeniuk et al., 2011
Ion and neutral chemsitry: NOx production N2+e*=>N++N(4S)+2e N2+e*=>N*+N(4S)+e N2+e*=>N2++2e N2++O=>NO++N(4S) N2+N+=>N2++N(4S) N2++e=>N*+N(4S) NO++e=>N(4S)+O N++O=>O++N(4S) N*+O2=>NO+O The process can be described adding five ions and relevan reactions to chemical scheme: O+, O2+, N+, N2+, NO+ Five ions are not enough for layer D (< 90 km)
Ion and neutral chemsitry: HOx production Ionization by particles below 90 km leads to the redistribution of NOy and enhancement of HOx From Sinnhuber et al., 2012
Ion and neutral chemsitry: Treatment in the models Above 90 km: 5-ion scheme – WACCM, HAMMONIA NOx (ppbv) from MIPAS. HEPPA-2, Courtesy of B. Funke
Ion and neutral chemsitry: Treatment in the models Below 90 km: Complete ion chemsitry (50+ species) - SOCOLi Computationally expensive Parameterizations of NOx and HOx production • Porter et al., 1976; Solomon et al., 1981 0.7 N*, 0.55 N(4S) and 2 HOx per ion pair; widely applied below 90 km (WACCM, HAMMONIA, EMAC, SOCOL...)
NOx and HOx production Widely used parameterization (0.7 N* + 0.55 N(4S) + up to 2 HOx per Ion Pair) against complete ion chemistry CCM SOCOL (Egorova et al., 2011)
Ion and neutral chemsitry: Treatment in the models Below 90 km: • Verronen and Lehman, 2013 LUT, includes HNO3 production • Nieder et al., 2014 (LUT) LUT
Transport, HEPPA-2 project
Treatment of the auroral electrons in low top CCMs (EMAC, SOCOL) Baumgartner et al, 2009
Effects of the solar protons MIPAS MMM Observed and modeled NOy enhancement during October 2003 SPE, 70–90oN, Funke et al., 2011
Ozone depletion by NOx and HOx Nitrogen: NO + O3 → NO2 + O2 NO2 + O → NO + O2 ========================== O3 + O → 2O2 Hydrogen: OH + O3 → HO2 + O2 HO2 + O → OH + O2 ========================== O3 + O → 2O2 From D. Lary
Effects of the solar protons MMM MIPAS Observed and modeled O3 depletion after the October 2003 SPE, 70–90oN, Funke et al., 2011
Effects of EPP on NOx NOx, (%) due to EPP averaged over 60o-90oS
EP influence on ozone climatology Ozone change by EPP, 70-90oN, CCM SOCOL v2.0, Rozanov et al., 2012
Cooling rate due to polar ozone depletion January Polar AER LBL code
Downward propagating responseor ‘top-down’ route EPP cooling and O3 decrease Solar UV heating and O3 increase Thomson & Wallace (1998) Hadley sell shift and ... (J.Haigh) Kodera and Kuroda, (2002)
EP influence on surface air temperature DJF, UIUC CCM, RE Rozanov et al., 2005 DJF, SOCOL v2.0, all EP Rozanov et al., 2012 NDJ composite High D1- Low D1 from GISS Maliniemi et al., 2013 DJF composite High Ap-Low Ap SAT from ERA-40 JGR, 2009
The Deep Solar Minimum 2008 A long term prospective? • Long phase (780 days) without sunspots similar to 1913 • Solar activity not predictable
Evolution of the solar modulation potential from 10Be record (proxy for SSI) Abreu et al., 2010
The effects of Ap decrease on NOy Rozanov et al., 2012
Ozone changes after strong SPE (Carrington-like, August, 2020) From Calisto et al., 2013
SAT after strong SPE (Carrington-like, August, 2020) January, SAT, from Calisto et al., 2013
Conclusions • The progress in the modelling and understanding of the EP effects is evident: • The set of parameterizations for the treatment of EP effects in differnt models is available; • The magnitude of the EP influence is comparable with solar UV; • First time ever EP are included in the forcing set of CCMI • Challenges: • Parameterization for relativistic and middle energy electrons • Downward propagation of NOx from the lower thermosphere (HEPPA-2) • Climate response, understanding mechanisms behind top-down signal propagation • Projection of EP fluxes and spectrum behavior for future grand minimum of the solar activity