LONG-RANGE TRANSPORT OF BLACK CARBON TO THE ARCTIC REGION
Qinbin Li1, Daven Henze2, Yang Chen1,
Evan Lyons3, Jim Randerson3
work supported by JPL/NASA
1JPL 2Caltech 3UC Irvine
Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS)
ARCTAS to be conducted in spring and summer 2008 (two phases)as part of the POLARCAT program during the International Polar Year (IPY)
ARCTAS
EXPORT OF BC FROM ASIA: GEOS-3 vs. GEOS-4
STRONGER EXPORT OF BC IN THE FREE TROPOSPHERE WITH GEOS-Chem DRIVEN BY GEOS4 MET DATA.
Vertical distributions of BC during TRACE-P
Park et al. [2005]
GEOS-3
GEOS-4
TRACE-P OBS.
TRACE-P OBS.
Monthly BC profiles [124-140°E, 30-40°N]
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?
MEASUREMENTS OF BC IN HIGH-LATITUDES
BC @ ALERT (62.8ºW, 82.7ºN)
- 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/)
Green - CMDL obs.Blue - GC w/ GEOS-3Red - GC w/ GEOS-4
need to filter out contamination
- 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.
BC @ BARROW (156.6ºE, 71.3ºN)
Green - CMDL obs.Blue - GC w/ GEOS-3Red - GC w/ GEOS-4
Data from CMDL (ftp.cmdl.noaa.gov/aerosol/)
Mass absorption efficiency - 10 m2/g
(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.
BC EMISSIONS
SENTIVITY
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 EMISSIONSJuly 2001
SURFACE ~750-400 hPa
SURFACE ~750-400 hPa
Fossil Fuel
Biomass burning
BC AOD with monthly GFED emissionsBC AOD with 8-day GFED emissions
including diurnal cycle
TRANSPORT OF BOREAL FOREST FIRE BC EMISSIONS: effects of including (fire) diurnal cycle
Including diurnal cycle of fires results in less efficient transport of boreal forest fire emissions in Alaska while more efficient in southern Africa.
T
WIND
RH
PRECIP
ISI
GOES FIRE COUNTS
INITIAL SPREAD INDEX AND MODELED EMISSIONS FOR ALASKA
EMISSIONS