 |
| Titel |
Anthropogenic emissions during Arctas-A: mean transport characteristics and regional case studies |
| VerfasserIn |
D. L. Harrigan, H. E. Fuelberg, I. J. Simpson, D. R. Blake, G. R. Carmichael, G. S. Diskin |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 11, no. 16 ; Nr. 11, no. 16 (2011-08-25), S.8677-8701 |
| Datensatznummer |
250010029
|
| Publikation (Nr.) |
 copernicus.org/acp-11-8677-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
The National Aeronautics and Space Administration (NASA) conducted the
Arctic Research of the Composition of the Troposphere from Aircraft and
Satellites (ARCTAS) mission during 2008 as a part of the International Polar
Year (IPY). The purpose of ARCTAS was to study the factors responsible for
changes in the Arctic's atmospheric composition and climate. A major
emphasis was to investigate Arctic haze, which is most pronounced during
winter and early spring. This study focuses on the spring phase of ARCTAS
(ARCTAS-A) that was based in Alaska during April 2008. Although
anthropogenic emissions historically have been associated with Arctic haze,
biomass burning emissions dominated the ARCTAS-A period and have been the
focus of many ARCTAS related studies.
This study determines mean transport characteristics of anthropogenic
emissions during ARCTAS-A. Trajectories are initiated each day from three
significant regions of anthropogenic emissions (Asia, North America, and
Europe). The fifteen day forward trajectories are calculated using data from
the Weather Research and Forecasting (WRF) model at 45 km horizontal
resolution. The trajectory calculations indicate: origins of emissions that
reach the Arctic (defined as north of 70° N) within fifteen days,
pathways of these emissions, Arctic entry locations, and altitudes at which
the trajectories enter the Arctic.
Three cases during the ARCTAS-A period (one for each of the regions above)
are examined using backward trajectories and chemical fingerprinting based
on in situ data sampled from the NASA DC-8. The fingerprinting utilizes
volatile organic compounds that represent pure anthropogenic tracers, Asian
anthropogenic pollution, incomplete combustion, and natural gas emissions.
We determine flight legs containing anthropogenic emissions and the pathways
travelled by these emissions. Results show that the DC-8 sampled
anthropogenic emissions from Asia, North America, and Europe during the
spring phase of ARCTAS. The pathways travelled by these emissions agree with
our derived transport characteristics and previous studies of Arctic
transport. Meteorological analysis and trajectory calculations indicate that
middle latitude cyclones and their associated warm conveyor belts play an
important role in lofting the surface based emissions to their sampling
altitude in all three cases. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|