Nowcasting of neutral and ion composition of the mesosphere: Ionosphere chemistry module. Egorova, T., E. Rozanov, J.-F. Hochedez, and W. Schmutz PMOD/WRC, Davos, Switzerland ROB, Brussels, Belgium SCSL meeting, 29 Nov.-1 Dec., 2006

LYRA Instrument on PROBA2 The project idea: To evaluate the response of the middle atmosphere to the solar UV irradiance variability LYRA Instrument on PROBA2 tools for nowcast and short-term forecast of the solar irradiance (solar spectral restoration) On-line LYRA data and nowcast/forecast results for space-weather community Other observations of solar irradiance Chemistry ionosphere climate model (CICM) extension of SOCOL (Egorova et al.,2005) Nowcast and short-term forecast of the neutral and ionic composition of the middle atmosphere

GCM CTM Modeling tool description SOCOL : modeling tool to study SOlar-Climate-Ozone Links General Circulation component (GCM): MA-ECHAM4 (Manzini & McFarlane,1998) Chemistry/transport component (CTM) : MEZON (Egorova et al., 2003) Main features: ~4ºx4º (T30); L39; ~80km Winds and temperature H2O (troposphere) Ported on PC (3.8 GHz): 3 hours => ~ 18 s CPU Documentation: Egorova et al., 2005, ACP GCM CTM Ozone H2O(stratosphere)

Solar irradiance at 205 nm

Maximum correlation with I205nm from CCM Hydroxyl Temperature Ozone

Ozone at 40 km from CCM

Comparison 3D simulation and observations: signal of 27-day solar cycle in ozone Red: Ly-alpha Blue: Herzberg (scaled) SUSIM Microwave radiometer: Data provided by Bern University (N.Kämpfer group) SOMORA SOCOL calculations: without ionosphere SOCOL

Maximum correlation with I205nm from CCM Hydroxyl Temperature Ozone

Hydroxyl at 50 km from CCM

Ion chemistry in the D-region: 1-D model Space: 0-90 km, Z = ~ 2 km Time : t = 2 hours Chemistry: Electron density: e 30 positive ions: O+, O2+, O4+, N+, NO+, N2+, H2O2+, H3O+,O2+∙N2, O2+∙H2O, H3O+∙OH, NO+∙H2O, NO+∙(H2O)2, NO+∙(H2O)3, NO+∙CO2, NO+∙N2, NO+∙H2O∙CO2, NO+∙H2O∙N2, NO+∙(H2O)2∙CO2, NO+∙(H2O)2∙N2, H+∙(H2O)2, H+∙(H2O)3, H+∙(H2O)4, H+∙(H2O)5, H+∙(H2O)6, H+∙(H2O)7, H3O+∙CO2, H3O+∙N2, H+∙(H2O)2∙CO2, H+∙(H2O)2∙N2 17 negative ions: O¯, O2¯, O3¯, O4¯, OH¯, CO3¯, CO4¯, NO2¯, NO3¯, HCO3¯, ClO¯, Cl¯, CH3¯,O2¯∙H2O, NO3¯∙H2O, CO3¯∙H2O 43 neutral species: O3 , O* , O , O2*, NO, HO2, ClO, NO2 , OH, NO3, N2O5, HNO3,HONO3, ClONO2, Cl, N, N*, H2O2, H, HOCl, Cl2, Cl2O2, HCl ,Br, CH2O, BrO, HBr, HOBr, BrNO3, BrCl, CH3, CH3O2, CH3O, HCO, CH3O2H, H2O, CFC-11, CFC-12, N2O, CH4, CO, H2, CBrF3 ~ 200 reactions for ions and ~ 200 neutral gaseous reactions

Ion chemistry in the D-region: 1-D model Ionization: - Ly-alpha above 65 km: NO - Galactic Cosmic Rays below 65 km (Heaps, 1978): N2 and O2 - Energetic Particles Precipitation (EPP) - Solar Proton Events (SPE) Radiation: - spectral region 120-780 nm with 73 spectral intervals (Rozanov et al., 2002) - radiation data source: daily SUSIM UARS observations Simulations performed for 500N, for max and min solar activity

Vertical distribution of electron and total negative ( N- ) and positive (N+) ions density

Daily cycle

Sensitivity study: Solar max- solar min Positive ions Negative ions and electrons Experiments: 1) – 2) Solar maximum with GCR at min + NO ionization Solar minimum control with GCR at max + NO ionization Neutrals

Nowcasting in the D-region: request for hourly data Data in use: LYRA measurements of Ly-alpha and Herzberg fluxes INPUT: sol. sp. reconstruction (how ???) Solar spectrum forecast (up to 3-4 hours) (how ???) Comparison with obs. Availability from web Tool for nowcast: free running global CCM: CICM (SOCOL with ion chemistry) 3-hour long ensemble run (~10) 1 hour – time step Output parameters 3D anomalies: e, NO+, O2+, O2-, O- O3, OH, NO, H2O - T, U

More frequent data input allows the forecast with Solar rad. flux GCR flux SPE flux EEP flux Sun_cur.dat Neutron_cur.dat SPE_cur.dat EEP_cur.dat not important for D-region ? important only for high geom.lat ? Sun_nowcast.dat (t = 1, 2 h) More frequent data input allows the forecast with higher precision 0 hour 1 hour 2 hour 3 hour Takes into account radiation changes every hour