SO 2 from TOVS Prata Bates and Jackson

SO 2 from TOVS, Prata, Bates and Jackson A New Method for the Retrieval of Upper Troposphere/Lower Stratosphere Sulfur Dioxide from Global Long-term TOVS Measurements Fred Prata, CSIRO Atmospheric Research, Australia John Bates, NOAA-ETL, USA Darren Jackson, NOAA-ETL, USA 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson SO 2 Budgets Source SO 2 SO 4 Fossil-fuel combustion +industry 70 2. 2 Biomass burning 2. 8 0. 1 Oceans – 40– 320 Plants+soils – 2– 4 Volcanoes 7– 8 2– 4 Units: Tg(S) yr-1 27 Feb - 5 March, 2002 Source: Berresheim et al. (1995) ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson The volcanic plume from Hekla on 29 th of February 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Infrared image (11 µm) x Encounter 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Difference image (11 -12 µm) x Encounter 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 7. 3 µm image x Encounter 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 27 Feb - 5 March, 2002 27 D. U. ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 24 D. U. TOMS SO 2 (m atm-cm) 27 February, 2000 30 18 6 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson MODIS channels and SO 2 Line Strengths 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson SO 2 line strengths Transmission Brightness temperature (t. o. a) Difference (Kelvin) 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Weighting functions and transmission vs absorber amount 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson MODTRAN simulations 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson The Retrieval Scheme: • Get radiances for HIRS channels 8 (11. 11 µm), 11 (7. 34 µm) and 12 (6. 76 µm) • Synthesise 7. 3 µm channel from the 6. 7 µm and 11. 1 µm channels by linear interpolation in radiance • Compute difference DT=T*7. 3 -T 7. 3 (T* is the synthetic BT) • Exclude pixels with T 11 < 220 K • Compute SO 2 amount using model from RT simulations: Log 10[SO 2]=c 0+c 1 DT+c 2 DT 2+c 3 DT 3 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson MODIS retrieval for Hekla, Feb 2000 eruption Approximate aircraft track 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson SOLVE (NASA DC-8) in situ SO 2 measurements and MODIS retrievals show good agreement Integrated across plume: SOLVE=248 ppm. V MODIS=241 ppm. V 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson TOVS 27 Feb - 5 March, 2002 TOMS ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson TOVS 27 Feb - 5 March, 2002 TOMS ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Eruption of Cerro Hudson, southern Chile 7 -27 August, 1991 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Very cold scene temperatures (T<220 K) cause anomalies in retrieval scheme 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Anomalies are removed by excluding pixels where T 11< 220 K SO 2 above very cold surfaces difficult to retrieve by this method 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Different orbits give different mass loadings, but very similar mass densities NOAA-10 -> 0. 653 t km-2 (mass loading=0. 98 Mt) NOAA-11 -> 0. 658 t km-2 (mass loading=0. 33 Mt) NOAA-12 -> 0. 655 t km-2 (mass loading=0. 86 Mt) 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Mt St Helens, May, 1980 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Ash detection 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson SO 2 detection 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson Pinatubo 15 June - 15 July, 1991 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson CONCLUSIONS • SO 2 in the lower stratosphere and upper troposphere can be retrieved from the HIRS 7. 3 µm channel • Day/night, global, long-term (>22 years) capability • Ozone/SO 2 studies possible • Ash vs SO 2 vs H 2 SO 4 discrimination possible • Impact on humidity soundings using 7. 3 µm channel • (RT models should consider SO 2 absorption) • Climate applications - radiative effects using all TOVS channels 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria

SO 2 from TOVS, Prata, Bates and Jackson El Chichon, March 1982 27 Feb - 5 March, 2002 ITSC-XII Lorne, Victoria