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Modeling of the ozone layer evolution in the 21 st century. E. Rozanov 1,2 , V. Zubov 3 , T. Egorova 1 , I. Karol 3 , W. Schmutz 1 1 PMOD/WRC, Davos, Switzerland; 2 IAC ETH, Zurich, Switzerland; 3 MGO, St. Petersburg, Russia. Outline. Model description Experiments
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Modeling of the ozone layer evolution in the 21st century. E. Rozanov1,2, V. Zubov3, T. Egorova1, I. Karol3, W. Schmutz1 1PMOD/WRC, Davos, Switzerland; 2IAC ETH, Zurich, Switzerland; 3MGO, St. Petersburg, Russia
Outline • Model description • Experiments • Validation for 1975-2000 • Future versus past
Model SOCOL Modeling tool to study SOlar-Climate-Ozone Links Combination of MAECHAM-4 GCM and MEZON CTM
Winds and temperature • H2O (troposphere) GCM CTM • O3, CH4, N2O, CFCs • H2O(stratosphere) Model description 1 General Circulation component (GCM): MA-ECHAM4(Manzini & McFarlane, 1998) Chemistry/transport component (CTM) : MEZON(Egorova et al., 2003)
Model description 2 MA-ECHAM4 (Manzini&McFarlane, 1998) (Middle Atmosphere version of the “European Center/Hamburg Model 4”) Grid:spectral model with T30 ( ~4ºx4º); L39 hybrid sigma-pressure coordinate system; in the LS ~ 2 km; model top is 0.01hPa; Dynamics:t = 15 min; semi-implicit time stepping scheme with weak time filter Physical parameterizations: Radiation:t = 2 h SW: two-stream method for 0.25-0.68 and 0.68-4.0 mkm LW: broad-band flux emissivity method in 6 intervals Horizontal diffusion: in the form of a hyper-Laplasian with high-diffusion sponge zone near the upper boundary (~5 km) Gravity wave drug: orographic (McFarlane, 1987) and non-orographic (Hines, 1997) cloud formation, convective processes, planetary boundary layer, land-surface processes
Model description 3 MEZON (Egorova et al., 2003) (Model for Evaluation of the oZONe trends) Species: 41 from oxygen, nitrogen, hydrogen, carbon, chlorine and bromine groups, ~200 gas-phase and photolysis reactions Heterogeneous chemistry: 16 reactions on/in sulfate aerosol (binary and ternary solutions) and PSC particles, prescribed sulfate aerosol, thermo-dynamical scheme for PSC particles Chemical solver: implicit iterative Newton-Raphson scheme, t = 2 h Kinetics: JPL-1997, 2000 Photolysis rates: Look-up-table approach, updated to take into account the photo-dissociations in 120-170 nm (important for mesosphere) Transport:Hybrid advection scheme (Zubov et al., 1999): CSM scheme in vertical and SL scheme in horizontal directions
SOCOL publications • Validation: • Egorova et al., 2003, PAO • Egorova et al., 2005, ACP • Rozanov et al., 2005, ASR • 2. Application: Influence of solar variability on ozone and climate: • Egorova et al., 2004, GRL; Egorova et al., 2005, ASR; • Rozanov et al., 2005, SEC; Zubov et al, 2005, JASTP • Rozanov et al, 2005, JASTP; Rozanov et al., 2005, Mem. S.A.It.
Experiments • SST/SI + GHG + ODS • SST/SI + GHG + ODS + SA + SOLAR 1975 2050 1975 2000
Forcing 1975-2050 SST/SI past (Hadley data) SST/SI future (Hadley, AOGCM) GHG past (CMDL) GHG future (WMO-2003) ODS past (CMDL) ODS future (WMO-2003)
Forcing 1975-2000 Stratospheric aerosol (GISS) NASA-AMES SAGE
Forcing 1975-2000 Solar irradiance (Lean, 2000)
Past ozone trends 60oS 40oS 20oS 20oN 40oN 60oN From SOCOL, 1979-2000 WMO, 2002, from SAGE 1979-2000
Past temperature trend ~0.2 K/decade in the troposphere from observations SSU trends 1979-2003 From Randel, SPARC, 2004
Past temperature trend MSU T2, ~700 hPa Observation, (K/decade) 1979-2001, Santer et al., 2004 SOCOL, (K/decade) 1975-2000
Past temperature trend MSU T4, ~70 hPa SOCOL, (K/decade) 1975-2000 Observation, (K/decade) 1979-2001, Santer et al., 2004
Total ozone evolutions SOCOL: All forcing included SST+GHG+ODS TOMS/SBUV P C
DJF GPH 50 hPa ~2050 ~2001 19.3 km 19.6 km
DJF GPH 50 hPa (km) “2050”-”2001”
DJF Total ozone (DU) ~2050 ~2001
DJF Total ozone (DU) “2050”-”2001”
Conclusions • Cly: Fast increase in the past, slower decrease in the future, no recovery in the stratosphere in 2050. • Ozone: Fast decrease in the past, slower increase in the future, • Almost full recovery in ~2050 due to cooling. • Tstrat: steady cooling with different pattern in the future due to ozone increase • Ttrop: faster warming in the future due to faster CO2 and CH4 increase • Global total ozone: total recovery in ~2030 • NH total ozone: faster recovery (~2015) and steady increase due to dynamical changes • SH total ozone: slower recovery (~2050), ozone hole is still there • H2O: steady increase to 2050 due to CH4 and influx • CH4: change of the trend sign in the upper stratosphere • Dynamics: weaker NH vortex and intensification of BD circulation
Surface temperature trend Observation, (K/decade) 1979-2004 SOCOL, (K/decade) 1975-2000