 |
| Titel |
Continental outflow from the US to the upper troposphere over the North Atlantic during the NASA INTEX-NA Airborne Campaign |
| VerfasserIn |
S. Y. Kim, R. Talbot, H. Mao, D. Blake, S. Vay, H. Fuelberg |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 8, no. 7 ; Nr. 8, no. 7 (2008-04-08), S.1989-2005 |
| Datensatznummer |
250006031
|
| Publikation (Nr.) |
 copernicus.org/acp-8-1989-2008.pdf |
|
|
|
|
|
| Zusammenfassung |
| A case of continental outflow from the United States
(US) was examined using airborne measurements from NASA DC-8 flight 13
during the Intercontinental Chemical Transport Experiment – North America
(INTEX-NA). Mixing ratios of methane (CH4) and carbon monoxide (CO) at
8–11 km altitude over the North Atlantic were elevated to 1843 ppbv and
134 ppbv respectively, while those of carbon dioxide (CO2) and carbonyl
sulfide (COS) were reduced to 372.4 ppmv and 411 pptv respectively. In this
region, urban and industrial influences were evidenced by elevated mixing
ratios and good linear relationships between urban and industrial tracers
compared to North Atlantic background air. Moreover, low mixing ratios and a
good correlation between COS and CO2 showed a fingerprint of
terrestrial uptake and minimal dilution during rapid transport over a 1–2
day time period. Analysis of synoptic conditions, backward trajectories, and
photochemical aging estimates based on C3H8/C2H6
strongly suggested that elevated anthropogenic tracers in the upper
troposphere of the flight region were the result of transport via convection
and warm conveyor belt (WCB) uplifting of boundary layer air over the
southeastern US. This mechanism is supported by the similar slope values
of linear correlations between long-lived (months) anthropogenic tracers
(e.g., C2Cl4 and CHCl3) from the flight region and the
planetary boundary layer in the southeastern US. In addition, the aircraft
measurements suggest that outflow from the US augmented the entire
tropospheric column at mid-latitudes over the North Atlantic. Overall, the
flight 13 data demonstrate a pervasive impact of US anthropogenic
emissions on the troposphere over the North Atlantic. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|