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LONG-RANGE TRANSPORT OF BLACK CARBON TO THE ARCTIC REGION. Qinbin Li 1 , Daven Henze 2 , Yang Chen 1 , Evan Lyons 3 , Jim Randerson 3. 1 JPL 2 Caltech 3 UC Irvine. work supported by JPL/NASA.
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LONG-RANGE TRANSPORT OF BLACK CARBON TO THE ARCTIC REGION Qinbin Li1, Daven Henze2, Yang Chen1, Evan Lyons3, Jim Randerson3 1JPL 2Caltech 3UC Irvine work supported by JPL/NASA
Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) ARCTAS ARCTAS to be conducted in spring and summer 2008 (two phases) as part of the POLARCAT program during the International Polar Year (IPY)
EXPORT OF BC FROM ASIA: GEOS-3 vs. GEOS-4 Monthly BC profiles [124-140°E, 30-40°N] Vertical distributions of BC during TRACE-P GEOS-3 TRACE-P OBS. GEOS-4 Park et al. [2005] TRACE-P OBS. STRONGER EXPORT OF BC IN THE FREE TROPOSPHERE WITH GEOS-Chem DRIVEN BY GEOS4 MET DATA.
MEASUREMENTS OF BC IN HIGH-LATITUDES Long-term measurements of BC: - Alert (62.8ºW, 82.7ºN) mBC , ap (Aethalometer, PSAP) - Barrow (156.6ºE, 71.3ºN) ap (PSAP) - Ny Ålesund (11.9ºE, 78.9ºN) AOD (sun photometer) How well does the model simulate BC in northern high-latitudes?
BC @ ALERT (62.8ºW, 82.7ºN) Green - CMDL obs. Blue - GC w/ GEOS-3 Red - GC w/ GEOS-4 need to filter out contamination • BC component of the spring ‘Arctic Haze’ is significantly underestimated in the model. Better agreements for the summer months. • Little difference between the two model simulations driven by GEOS-3 vs. GEOS-4. Data from World Data Center for Aerosols (http://wdca.jrc.it/)
BC @ BARROW (156.6ºE, 71.3ºN) Green - CMDL obs. Blue - GC w/ GEOS-3 Red - GC w/ GEOS-4 Mass absorption efficiency - 10 m2/g • Underestimate of BC in ‘Arctic Haze’. • High BC levels from biomass burning in summer seen in both model results and (limited) observations. • Model results with GEOS-4 met. data show substantially higher BC values vs. those w/ GEOS-3 met. data. Data from CMDL (ftp.cmdl.noaa.gov/aerosol/)
(ADJOINT) SENSITIVITY OF ARCTIC TROPOSPHERIC (70-90°N, 800-400 hPa) BC LOADING TO EMISSIONS April 2001 DOMINANT INFLUENCE FROM EUROPEAN AND ASIA (CHINA) FOSSIL FUEL EMISSIONS. SENTIVITY BC EMISSIONS
SENSITIVITY OF ARCTIC BC LOADING TO FOSSIL FUEL EMISSIONS April 2001 SURFACE ~950-850 hPa ~750-400 hPa ~300-150 hPa
SENSITIVITY OF ARCTIC BC LOADING TO BIOMASS BURNING EMISSIONS April 2001 SURFACE ~950-850 hPa ~750-400 hPa ~300-150 hPa
(ADJOINT) SENSITIVITY OF ARCTIC TROPOSPHERIC (70-90°N, 800-400 hPa) BC LOADING TO EMISSIONS July 2001 DOMINANT INFLUENCE FROM BOREAL FOREST FIRE AND EUROPEAN FOSSIL FUEL EMISSIONS. SENTIVITY BC EMISSIONS
SENSITIVITY OF ARCTIC BC LOADING TO EMISSIONS July 2001 Fossil Fuel SURFACE ~750-400 hPa SURFACE ~750-400 hPa Biomass burning
TRANSPORT OF BOREAL FOREST FIRE BC EMISSIONS: effects of including (fire) diurnal cycle BC AOD with 8-day GFED emissions including diurnal cycle BC AOD with monthly GFED emissions Including diurnal cycle of fires results in less efficient transport of boreal forest fire emissions in Alaska while more efficient in southern Africa.
INITIAL SPREAD INDEX AND MODELED EMISSIONS FOR ALASKA EMISSIONS GOES FIRE COUNTS ISI PRECIP RH WIND T
GEOS Precipitation Alaska GPCP Precipitation Red: ISI modeled emissions, Green: GFED, Black: GOES