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  • American Geophysical Union (AGU)  (10)
  • 1
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    Chemical characteristics of continental outflow from Asia to the troposphere over the western Pacific Ocean during September–October 1991: Results from PEM‐West A
    American Geophysical Union (AGU) ; 1996
    In:  Journal of Geophysical Research: Atmospheres Vol. 101, No. D1 ( 1996-01-20), p. 1713-1725
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 101, No. D1 ( 1996-01-20), p. 1713-1725
    Abstract: An important objective of the Pacific Exploratory Mission‐West A (PEM‐West A) was the chemical characterization of the outflow of tropospheric trace gases and aerosol particles from the Asian continent over the western Pacific Ocean. This paper summarizes the chemistry of this outflow during the period September – October 1991. The vertical distributions of CO, C 2 H 6 , and NO x showed regions of outflow at altitudes below 2 km and from 8 to 12 km. Mixing ratios of CO were ≈130 parts per billion by volume (ppbv), ≈1000 parts per trillion by volume (pptv) for C 2 H 6 , and ≈100 pptv for NO x in both of these regions. Direct outflow of Asian industrial materials was clearly evident at altitudes below 2 km, where halocarbon tracer compounds such as CH 3 CCl 3 and C 2 Cl 4 were enhanced about threefold compared to aged Pacific air. The source attribution of species outflowing from Asia to the Pacific at 8–12 km altitude was not straightforward. Above 10 km altitude there were substantial enhancements of NO y , O 3 , CO, CH 4 SO 2 , C 2 H 6 , C 3 H 8 , C 2 H 2 , and aerosol 210 Pb but not halocarbon industrial tracers. These air masses were rich in nitrogen relative to sulfur and contained ratios of C 2 H 2 /CO and C 3 H 8 /C 2 H 6 (≈1.5 and 0.1 respectively) indicative of several‐day‐old combustion emissions. It is unclear if these emissions were of Asian origin, or if they were rapidly transported to this region from Europe by the high wind speeds in this tropospheric region (60 – 70 m s −1 ). The significant cyclonic activity over Asia at this time could have transported to the upper troposphere emissions from biomass burning in Southeast Asia or emissions from the extensive use of various biomass materials for cooking and space heating. Apparently, the emissions in the upper troposphere were brought there by wet convective systems since water‐soluble gases and aerosols were depleted in these air masses. Near 9 km altitude there was a distinct regional outflow that appeared to be heavily influenced by biogenic processes on the Asian continent, especially from the southeastern area. These air masses contained CH 4 in excess of 1800 ppbv, while CO 2 and OCS were significantly depleted (349 – 352 ppmv and 450 – 500 pptv, respectively). This signature seemingly reflected CH 4 emissions from wetlands and rice paddies with coincident biospheric uptake of tropospheric CO 2 and OCS.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/95JD01044
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1996
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  • 2
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    Chemical characteristics of continental outflow from Asia to the troposphere over the western Pacific Ocean during February‐March 1994: Results from PEM‐West B
    American Geophysical Union (AGU) ; 1997
    In:  Journal of Geophysical Research: Atmospheres Vol. 102, No. D23 ( 1997-12-20), p. 28255-28274
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 102, No. D23 ( 1997-12-20), p. 28255-28274
    Abstract: We present here the chemical composition of outflow from the Asian continent to the atmosphere over the western Pacific basin during the Pacific Exploratory Mission‐West (PEM‐West B) in February–March 1994. Comprehensive measurements of important tropospheric trace gases and aerosol particulate matter were performed from the NASA DC‐8 airborne laboratory. Backward 5 day isentropic trajectories were used to partition the outflow from two major source regions: continental north ( 〉 20°N) and continental south ( 〈 20°N). Air parcels that had not passed over continental areas for the previous 5 days were classified as originating from an aged marine source. The trajectories and the chemistry together indicated that there was extensive rapid outflow of air parcels at altitudes below 5 km, while aged marine air was rarely encountered and only at 〈 20°N latitude. The outflow at low altitudes had enhancements in common industrial solvent vapors such as C 2 Cl 4 , CH 3 CCl 3 , and C 6 H 6 , intermixed with the combustion emission products C 2 H 2 , C 2 H 6 , CO, and NO. The mixing ratios of all species were up to tenfold greater in outflow from the continental north compared to the continental south source region, with 210 Pb concentrations reaching 38 fCi (10 −15 curies) per standard cubic meter. In the upper troposphere we again observed significant enhancements in combustion‐derived species in the 8–10 km altitude range, but water‐soluble trace gases and aerosol species were depleted. These observations suggest that ground level emissions were lofted to the upper troposphere by wet convective systems which stripped water‐soluble components from these air parcels. There were good correlations between C 2 H 2 and CO and C 2 H 6 ( r 2 =0.70–0.97) in these air parcels and much weaker ones between C 2 H 2 and H 2 O 2 or CH 3 OOH ( r 2 ≈0.50). These correlations were the strongest in the continental north outflow where combustion inputs appeared to be recent (1–2 days old). Ozone and PAN showed general correlation in these same air parcels but not with the combustion products. It thus appears that several source inputs were intermixed in these upper tropospheric air masses, with possible contributions from European or Middle Eastern source regions. In aged marine air mixing ratios of O 3 (≈20 parts per billion by volume) and PAN (≤10 parts per trillion by volume) were nearly identical at 〈 2 km and 10–12 km altitudes due to extensive convective uplifting of marine boundary layer air over the equatorial Pacific even in wintertime. Comparison of the Pacific Exploratory Mission‐West A and PEM‐West B data sets shows significantly larger mixing ratios of SO 2 and H 2 O 2 during PEM‐West A. Emissions from eruption of Mount Pinatubo are a likely cause for the former, while suppressed photochemical activity in winter was probably responsible for the latter. This comparison also highlighted the twofold enhancement in C 2 H 2 , C 2 H 6 , and C 3 H 8 in the continental north outflow during PEM‐West B. Although this could be due to reduced OH oxidation rates of these species in wintertime, we argue that increased source emissions are primarily responsible.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/96JD02340
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1997
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  • 3
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    Atmospheric sampling of Supertyphoon Mireille with NASA DC‐8 aircraft on September 27,1991, during PEM‐West A
    American Geophysical Union (AGU) ; 1996
    In:  Journal of Geophysical Research: Atmospheres Vol. 101, No. D1 ( 1996-01-20), p. 1853-1871
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 101, No. D1 ( 1996-01-20), p. 1853-1871
    Abstract: The DC‐8 mission of September 27, 1991, was designed to sample air flowing into Typhoon Mireille in the boundary layer, air in the upper tropospheric eye region, and air emerging from the typhoon and ahead of the system, also in the upper troposphere. The objective was to find how a typhoon redistributes trace constituents in the West Pacific region and whether any such redistribution is important on the global scale. The boundary layer air (300 m), in a region to the SE of the eye, contained low mixing ratios of the tracer species O 3 , CO, C 2 H 6 , C 2 H 2 , C 3 H 8 , C 6 H 6 and CS 2 but high values of dimethylsulfide (DMS). The eye region relative to the boundary layer, showed somewhat elevated levels of CO, substantially increased levels of O 3 , CS 2 and all nonmethane hydrocarbons (NMHCs), and somewhat reduced levels of DMS. Ahead of the eye, CO and the NMHCs remained unchanged, O 3 and CS 2 showed a modest decrease, and DMS showed a substantial decrease. There was no evidence from lidar cross sections of ozone for the downward entrainment of stratospheric air into the eye region; these sections show that low ozone values were measured in the troposphere. The DMS data suggest substantial entrainment of boundary layer air into the system, particularly into the eye wall region. Estimates of the DMS sulphur flux between the boundary layer and the free troposphere, based on computations of velocity potential and divergent winds, gave values of about 69 μg S m −2 d −1 averaged over a 17.5° grid square encompassing the typhoon. A few hours after sampling with the DC‐8, Mireille passed over Oki Island, just to the north of Japan, producing surface values of ozone of 5.5 ppbv. These O 3 levels are consistent with the low tropospheric values found by lidar and are more typical of equatorial regions. We suggest that the central eye region may act like a Taylor column which has moved poleward from low latitudes. The high‐altitude photochemical environment within Typhoon Mireille was found to be quite active as evidenced by significant levels of measured gas phase H 2 O 2 and CH 3 OOH and model‐computed levels of OH.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/95JD01374
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1996
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  • 4
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    Summertime distribution and relations of reactive odd nitrogen species and NO y in the troposphere over Canada
    American Geophysical Union (AGU) ; 1994
    In:  Journal of Geophysical Research: Atmospheres Vol. 99, No. D1 ( 1994-01-20), p. 1863-1885
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 99, No. D1 ( 1994-01-20), p. 1863-1885
    Abstract: We report here large‐scale features of the distribution of NO x , HNO 3 , PAN, particle NO 3 − , and NO y in the troposphere from 0.15 to 6 km altitude over central Canada. These measurements were conducted in July–August 1990 from the NASA Wallops Electra aircraft as part of the joint United States‐Canadian Arctic Boundary Layer Expedition (ABLE) 3B‐Northern Wetlands Study. Our findings show that this region is generally NO x limited, with NO x mixing ratios typically 20–30 parts per trillion by volume (pptv). We found little direct evidence for anthropogenic enhancement of mixing ratios of reactive odd nitrogen species and NO y above those in“background”air. Instead, it appears that enhancements in the mixing ratios of these species were primarily due to emissions from several day old or CO‐rich‐NO x ‐poor smoldering local biomass‐burning fires. NO x mixing ratios in biomass‐burning impacted air masses were usually 〈 50 pptv, but those of HNO 3 and PAN were typically 100–300 pptv representing a twofold‐threefold enhancement over “background” air. During our study period, inputs of what appeared to be aged tropical air were a major factor influencing the distribution of reactive odd nitrogen in the midtroposphere over northeastern North America. These air masses were quite depleted in NO y (generally 〈 150 pptv), and a frequent summertime occurrence of such air masses over this region would imply a significant influence on the reactive odd nitrogen budget. Our findings show that the chemical composition of aged air masses over subarctic Canada and those documented in the Arctic during ABLE 3A have strikingly similar chemistries, suggesting large‐scale connection between the air masses influencing these regions.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/93JD01841
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1994
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  • 5
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    Airborne observations of spatial and temporal variability of tropospheric carbon dioxide
    American Geophysical Union (AGU) ; 1996
    In:  Journal of Geophysical Research: Atmospheres Vol. 101, No. D1 ( 1996-01-20), p. 1985-1997
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 101, No. D1 ( 1996-01-20), p. 1985-1997
    Abstract: Fast response (5‐s resolution) CO 2 measurements were recorded on two recent NASA‐sponsored airborne atmospheric chemical survey missions: the summer/fall 1991 Pacific Exploratory Mission‐West A (PEM‐West A) and the winter 1992 Airborne Arctic Stratospheric Expedition II (AASE II). Both missions were conducted aboard the NASA Ames Research Center DC‐8 aircraft and included sampling between the surface and 12‐km altitudes over a wide range of latitudes and longitudes. In the following text, these data, along with simultaneous surface measurements from the NOAA flask sampling network, are examined to establish the vertical distribution and variability of CO 2 as a function of location and season. Results indicate that middle to upper tropospheric ( 〉 5 km altitude) CO 2 concentrations often differ considerably ( 〉 5 parts per million by volume in some cases) from values recorded at surface stations within the same geographic region. These differences are particularly notable at middle to high northern latitudes where midtropospheric concentration changes and seasonal cycles are generally delayed in time and highly damped in amplitude relative to surface observations.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/95JD00413
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1996
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  • 6
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    The impact of U.S. continental outflow on ozone and aerosol distributions over the western Atlantic
    American Geophysical Union (AGU) ; 1993
    In:  Journal of Geophysical Research: Atmospheres Vol. 98, No. D12 ( 1993-12-20), p. 23477-23489
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 98, No. D12 ( 1993-12-20), p. 23477-23489
    Abstract: Aircraft measurements of selected trace gas species, aerosols, and meteorological parameters were performed in the lower troposphere off the U.S. east coast during August and September 1989 as part of the NASA Global Tropospheric Experiment (GTE) Chemical Instrumentation Test and Evaluation (CITE 3) expedition. In this paper, we examine these data to assess the impact of continental outflow on western Atlantic O 3 and small aerosol budgets. Results show that mixed layer (ML) O 3 concentrations and small aerosol number densities (Np) were enhanced by factors of 3 and 6, respectively, within air masses of predominantly continental origin compared with clean maritime background air. These enhancements exhibited a marked altitude dependence, declining rapidly above the ML to the point where only slight to moderate differences in O 3 and Np, respectively, were notable above 2.4 km. Within continentally influenced ML's, both O 3 and Np were correlated with CO, exhibiting linear regression slopes averaging 0.4 ppbv(O 3 )/ppbv(CO) for O 3 and 7.7 (particles cm −3 )/ppbv(CO) for Np and indicating a primarily anthropogenic origin for the observed enhancement of these species. Comparisons between profiles in continental and background maritime air masses suggest that photochemical production below 1.4‐km altitude adds over 10% to western Atlantic tropospheric column O 3 abundance in continental outflow regimes. For aerosols, eastward advection of low‐level continental air contributes an average net flux of 2.8 metric tons of submicron (accumulation mode) particles per kilometer of shoreline per day to the western Atlantic troposphere.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/93JD01208
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1993
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  • 7
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    Large‐scale distributions of tropospheric nitric, formic, and acetic acids over the western Pacific basin during wintertime
    American Geophysical Union (AGU) ; 1997
    In:  Journal of Geophysical Research: Atmospheres Vol. 102, No. D23 ( 1997-12-20), p. 28303-28313
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 102, No. D23 ( 1997-12-20), p. 28303-28313
    Abstract: We report here measurements of the acidic gases nitric (HNO 3 ), formic (HCOOH), and acetic (CH 3 COOH) over the western Pacific basin during the February‐March 1994 Pacific Exploratory Mission‐West (PEM‐West B). These data were obtained aboard the NASA DC‐8 research aircraft as it flew missions in the altitude range of 0.3–12.5 km over equatorial regions near Guam and then further westward encompassing the entire Pacific Rim arc. Aged marine air over the equatorial Pacific generally exhibited mixing ratios of acidic gases 〈 100 parts per trillion by volume (pptv). Near the Asian continent, discrete plumes encountered below 6 km altitude contained up to 8 parts per billion by volume (ppbv) HNO 3 and 10 ppbv HCOOH and CH 3 COOH. Overall there was a general correlation between mixing ratios of acidic gases with those of CO, C 2 H 2 , and C 2 Cl 4 , indicative of emissions from combustion and industrial sources. The latitudinal distributions of HNO 3 and CO showed that the largest mixing ratios were centered around 15°N, while HCOOH, CH 3 COOH, and C 2 Cl 4 peaked at 25°N. The mixing ratios of HCOOH and CH 3 COOH were highly correlated ( r 2 = 0.87) below 6 km altitude, with a slope (0.89) characteristic of the nongrowing season at midlatitudes in the northern hemisphere. Above 6 km altitude, HCOOH and CH 3 COOH were marginally correlated ( r 2 = 0.50), and plumes well defined by CO, C 2 H 2 , and C 2 Cl 4 were depleted in acidic gases, most likely due to scavenging during vertical transport of air masses through convective cloud systems over the Asian continent. In stratospheric air masses, HNO 3 mixing ratios were several parts per billion by volume (ppbv), yielding relationships with O 3 and N 2 O consistent with those previously reported for NO y .
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/96JD02975
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1997
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  • 8
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    Factors influencing the upper free tropospheric distribution of reactive nitrogen over the South Atlantic during the TRACE A experiment
    American Geophysical Union (AGU) ; 1996
    In:  Journal of Geophysical Research: Atmospheres Vol. 101, No. D19 ( 1996-10-30), p. 24165-24186
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 101, No. D19 ( 1996-10-30), p. 24165-24186
    Abstract: This paper evaluates the potential sources of the enhanced levels of NO that were observed throughout the upper troposphere over the equatorial and tropical South Atlantic. During September/October 1992 NO x (NO + NO 2 ) mixing ratios in the 8‐ to 13‐km region averaged 150 parts per trillion by volume (pptv) and were greatly affected by what appeared as spatially large “plumes” (100 to 1000 km) with NO enhancements of over 800 parts per trillion by volume. Other trace gases were also enhanced within these plumes (e.g., CO, CO 2 , CH 4 , CH 3 Cl, C 2 H 2 , C 2 H 6 , C 3 H 8 , and PAN). However, for these tracers of surface emissions, inconsistent patterns of enhancement were found with respect to one another and to NO. We analyzed these plumes for indications of coherent relationships between the enhanced levels of NO and the enhanced levels of biogenic and combustion‐related tracers. This analysis indicated that the tracer relationships were primarily produced by their common injection via deep convection into the upper troposphere. A corollary analysis using a combustion tracer reference frame in combination with meteorological analysis indicates a longer than expected lifetime of NO x in the upper troposphere. This analysis also suggests that an efficient mechanism may exist in the upper troposphere for recycling HNO 3 back into NO x with a rate comparable to that predicted for the HNO 3 formation. During the Transport and Atmospheric Chemistry Near the Equator Atlantic study period this in‐situ formation of NO x is estimated to provide the equivalent of approximately 0.7 TgN/yr of NO x within the South Atlantic basin's upper troposphere. This magnitude of local in situ source is estimated to be comparable to the combined inputs from lightning and biomass burning, which are both injected via deep convection. Our analysis also suggests that lightning can contribute as much as half of the external input of NO x into this region of the upper troposphere with biomass burning possibly representing the remainder.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/96JD00224
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1996
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  • 9
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    Factors influencing dry season ozone distributions over the tropical South Atlantic
    American Geophysical Union (AGU) ; 1993
    In:  Journal of Geophysical Research: Atmospheres Vol. 98, No. D12 ( 1993-12-20), p. 23491-23500
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 98, No. D12 ( 1993-12-20), p. 23491-23500
    Abstract: Airborne measurements of trace gas and aerosol species were obtained in the lower troposphere ( 〈 5km) over the western Atlantic Ocean between 13°S and 40°N during the August/September 1990 NASA Chemical Instrument Test and Evaluation (CITE 3) experiment. The largest background O 3 mixing ratios, averaging 35 and 70 ppbv within the mixed layer (ML) and free troposphere (FT; altitudes 〉 2.4 km), respectively, were found over the tropical South Atlantic. Several competing processes were observed to regulate O 3 budgets in this region. Within the ML, rapid photochemical destruction produced a diurnal O 3 variation of 8 ppbv and an O 3 /altitude gradient between the surface and 5 km of almost 10 ppbv(O 3 ) km −1 . ML O 3 concentrations were replenished by atmospheric downwelling which occurred at rates of up to and exceeding 1 cm s −1 . Ozone values within the subsiding FT air were enriched both by long‐range transport of O 3 produced photochemically within biomass combustion plumes and the downward propagation of dry, upper tropospheric air masses. Overall, the tropospheric O 3 column below 3.3 km averaged 13.5 Dobson units (DU) over the South Atlantic region, which is 8–9 DU higher than observed during CITE 3 ferry flights over the northern tropical Atlantic Ocean or measured by ozonesondes over coastal Brazil during the wet season. An examination of simultaneous dew point and combustion tracer (e.g., CO) measurements suggests that the dry subsiding layers and biomass burning layers make approximately equal contributions to the observed O 3 enhancement.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/93JD01361
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1993
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    Chemical characteristics of continental outflow over the tropical South Atlantic Ocean from Brazil and Africa
    American Geophysical Union (AGU) ; 1996
    In:  Journal of Geophysical Research: Atmospheres Vol. 101, No. D19 ( 1996-10-30), p. 24187-24202
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 101, No. D19 ( 1996-10-30), p. 24187-24202
    Abstract: The chemical characteristics of air parcels over the tropical South Atlantic during September – October 1992 are summarized by analysis of aged marine and continental outflow classifications. Positive correlations between CO and CH 3 Cl and minimal enhancements of C 2 Cl 4 and various chlorofluorocarbon (CFC) species in air parcels recently advected over the South Atlantic basin strongly suggest an impact on tropospheric chemistry from biomass burning on adjacent continental areas of Brazil and Africa. Comparison of the composition of aged Pacific air with aged marine air over the South Atlantic basin from 0.3 to 12.5 km altitude indicates potential accumulation of long‐lived species during the local dry season. This may amount to enhancements of up to two‐fold for C 2 H 6 , 30% for CO, and 10% for CH 3 Cl. Nitric oxide and NO x were significantly enhanced (up to ∼1 part per billion by volume (ppbv)) above 10 km altitude and poorly correlated with CO and CH 3 Cl. In addition, median mixing ratios of NO and NO x were essentially identical in aged marine and continental outflow air masses. It appears that in addition to biomass burning, lightning or recycled reactive nitrogen may be an important source of NO x to the upper troposphere. Methane exhibited a monotonic increase with altitude from ∼1690 to 1720 ppbv in both aged marine and continental outflow air masses. The largest mixing ratios in the upper troposphere were often anticorrelated with CO, CH 3 Cl, and CO 2 , suggesting CH 4 contributions from natural sources. We also argue, based on CH 4 /CO ratios and relationships with various hydrocarbon and CFC species, that inputs from biomass burning and the northern hemisphere are unlikely to be the dominant sources of CO, CH 4 , and C 2 H 6 in aged marine air. Emissions from urban areas would seem to be necessary to account for the distribution of at least CH 4 and C 2 H 6 . Over the African and South American continents an efficient mechanism of convective vertical transport coupled with large‐scale circulations conveys biomass burning, urban, and natural emissions to the upper troposphere over the South Atlantic basin. Slow subsidence over the eastern South Atlantic basin may play an important role in establishing and maintaining the rather uniform vertical distribution of long‐lived species over this region. The common occurrence of values greater than 1 for the ratio CH 3 OOH/H 2 O 2 in the upper troposphere suggests that precipitation scavenging effectively removed highly water soluble gases (H 2 O 2 , HNO 3 , HCOOH, and CH 3 COOH) and aerosols during vertical convective transport over the continents. However, horizontal injection of biomass burning products over the South Atlantic, particularly water soluble species and aerosol particles, was frequent below 6 km altitude.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/95JD03630
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1996
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