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2. A new interpretation of total column BrO during Arctic spring

Author

Salawitch, RJ, Canty, T, Kurosu, T, Chance, K, Liang, Q, da Silva, A, Pawson, S, Nielsen, JE, Rodriguez, JM, Bhartia, PK, Liu, X, Huey, LG, Liao, J, Stickel, RE, Tanner, DJ, Dibb, JE, Simpson, WR, Donohoue, D, Weinheimer, A, Flocke, F, Knapp, D, Montzka, D, Neuman, JA, Nowak, JB, Ryerson, TB, Oltmans, S, Blake, DR, Atlas, EL, Kinnison, DE, Tilmes, S, Pan, LL, Hendrick, F, Van Roozendael, M, Kreher, K, Johnston, PV, Gao, RS, Johnson, B, Bui, TP, Chen, G, Pierce, RB, Crawford, JH, and Jacob, DJ

Subjects
Climate Action, Meteorology & Atmospheric Sciences
Abstract

Emission of bromine from sea-salt aerosol, frost flowers, ice leads, and snow results in the nearly complete removal of surface ozone during Arctic spring. Regions of enhanced total column BrO observed by satellites have traditionally been associated with these emissions. However, airborne measurements of BrO and O3 within the convective boundary layer (CBL) during the ARCTAS and ARCPAC field campaigns at times bear little relation to enhanced column BrO. We show that the locations of numerous satellite BrO "hotspots" during Arctic spring are consistent with observations of total column ozone and tropopause height, suggesting a stratospheric origin to these regions of elevated BrO. Tropospheric enhancements of BrO large enough to affect the column abundance are also observed, with important contributions originating from above the CBL. Closure of the budget for total column BrO, albeit with significant uncertainty, is achieved by summing observed tropospheric partial columns with calculated stratospheric partial columns provided that natural, short-lived biogenic bromocarbons supply between 5 and 10 ppt of bromine to the Arctic lowermost stratosphere. Proper understanding of bromine and its effects on atmospheric composition requires accurate treatment of geographic variations in column BrO originating from both the stratosphere and troposphere. Copyright 2010 by the American Geophysical Union.

Published
2010

4. Neutralizing activities of human immunoglobulin derived from donors in Japan against mosquito-borne flaviviruses, Japanese encephalitis virus, West Nile virus, and dengue virus

Author

Yunoki M, Kurosu T, Koketsu RK, Takahashi K, Okuno Y, and Ikuta K

Subjects
Japanese encephalitis virus, West Nile virus, Dengue virus, intravenous immunoglobulin, neutralization, Medicine (General), R5-920
Abstract

Mikihiro Yunoki,1-3 Takeshi Kurosu,2 Ritsuko Kubota Koketsu,2,4 Kazuo Takahashi,5 Yoshinobu Okuno,4 Kazuyoshi Ikuta2,4 1Research and Development Division, Japan Blood Products Organization, Tokyo, 2Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 3Pathogenic Risk Evaluation, Graduate School of Veterinary Medicine, Rakuno Gakuen University, Hokkaido, 4Research and Development Division, The Research Foundation for Microbial Diseases of Osaka University, Kagawa, 5Osaka Prefectural Institute of Public Health, Osaka, Japan Abstract: Japanese encephalitis virus (JEV), West Nile virus (WNV), and dengue virus (DenV) are causal agents of Japanese encephalitis, West Nile fever, and dengue fever, respectively. JEV is considered to be indigenized and widespread in Japan, whereas WNV and DenV are not indigenized in Japan. Globulin products seem to reflect the status of the donor population according to antivirus neutralization activity. However, the anti-JEV, -WNV, and -DenV neutralization activities of globulin products derived from donors in Japan have not been clarified. Furthermore, potential candidates for the development of an effective immunotherapeutic drug for encephalitis caused by JEV, WNV, or DenV have also not been identified. Therefore, the aim of this study was to determine the overall status of the donor population in Japan based on globulin products by evaluating anti-JEV, -WNV, and -DenV neutralizing activities of intravenous immunoglobulin. Overall, intravenous immunoglobulin products showed stable neutralizing activity against JEV but showed no or only weak activity against WNV or DenV. These results suggest that the epidemiological level against WNV and DenV in the donor population of Japan is still low, suggesting that these viruses are not yet indigenized. In addition, JEV vaccinations and/or infections in the donor population do not induce a cross-reactive antibody against WNV. Keywords: Japanese encephalitis virus, West Nile virus, dengue virus, intravenous immunoglobulin, neutralization

Published
2016

6. Link Between Arctic Tropospheric BrO Explosion Observed from Space and Sea-Salt Aerosols from Blowing Snow Investigated Using Ozone Monitoring Instrument BrO Data and GEOS-5 Data Assimilation System

Author

Choi, S, Theys, N, Salawitch, R. J, Wales, P. A, Joiner, J, Canty, T. P, Chance, K, Suleiman, R. M, Palm, S. P, Cullather, R. I, Darmenov, A. S, da Silva, A, Kurosu, T. P, Hendrick, F, and Van Roozendael, M

Subjects
Earth Resources And Remote Sensing
Abstract

Bromine radicals (Br + BrO) are important atmospheric species owing to their ability to catalytically destroy ozone as well as their potential impacts on the oxidative pathways of many trace gases, including dimethylsulfide and mercury. Using space-based observations of BrO, recent studies have reported rapid enhancements of tropospheric BrO over large areas (so called "BrO explosions") connected to near-surface ozone depletion occurring in polar spring. However, the source(s) of reactive bromine and mechanism(s) that initiate these BrO explosions are uncertain. In this study, we investigate the relationships between Arctic BrO explosions and two of the proposed sources of reactive bromine: sea-salt aerosol (SSA) generated from blowing snow and first-year (seasonal) sea ice. We use tropospheric column BrO derived from the Ozone Monitoring Instrument (OMI) in conjunction with the Goddard Earth Observing System Version 5 (GEOS-5) data assimilation system provided by National Aeronautics and Space Administration Global Modeling and Assimilation Office. Case studies demonstrate a strong association between the temporal and spatial extent of OMI-observed BrO explosions and the GEOS-5 simulated blowing snow-generated SSA during Arctic spring. Furthermore, the frequency of BrO explosion events observed over the 11-year record of OMI exhibits significant correlation with a time series of the simulated SSA emission flux in the Arctic and little to no correlation with a time series of satellite-based first-year sea ice area. Therefore, we conclude that SSA generated by blowing snow is an important factor in the formation of the BrO explosion observed from space during Arctic spring.

Published
2018
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7. Cross-reactivity of human monoclonal antibodies generated with peripheral blood lymphocytes from dengue patients with Japanese encephalitis virus

Author

Pipattanaboon C, Sasaki T, Nishimura M, Setthapramote C, Pitaksajjakul P, Leaungwutiwong P, Limkittikul K, Puiprom O, Sasayama M, Chaichana P, Okabayashi T, Kurosu T, Ono K, Ramasoota P, and Ikuta K

Subjects
Medicine (General), R5-920
Abstract

Chonlatip Pipattanaboon,1,3,8,* Tadahiro Sasaki,2,8,* Mitsuhiro Nishimura,2,8 Chayanee Setthapramote,1,8 Pannamthip Pitaksajjakul,1,4,8 Pornsawan Leaungwutiwong,1,3,8 Kriengsak Limkittikul,5,8 Orapim Puiprom,6 Mikiko Sasayama,6 Panjaporn Chaichana,6 Tamaki Okabayashi,6 Takeshi Kurosu,2,8 Ken-ichiro Ono,7,8 Pongrama Ramasoota,1,4,8 Kazuyoshi Ikuta2,8 1Center of Excellence for Antibody Research, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; 2Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan; 3Department of Microbiology and Immunology, 4Department of Social and Environmental Medicine, 5Department of Tropical Pediatrics, Faculty of Tropical Medicine, Mahidol University, 6Mahidol-Osaka Center for Infectious Diseases, Bangkok, Thailand; 7Medical and Biological Laboratories Corporation Ltd, Nagano, Japan; 8JST/JICA, Science and Technology Research Partnership for Sustainable Development, Tokyo, Japan *These authors made an equal contribution to this study Background: Hybridomas that produce human monoclonal antibodies (HuMAbs) against Dengue virus (DV) had been prepared previously using peripheral blood lymphocytes from patients with DV during the acute and convalescent phases of a secondary infection. Anti-DV envelope glycoprotein (E) 99 clones, anti-DV premembrane protein (prM) 8 clones, and anti-DV nonstructural protein 1 (NS1) 4 clones were derived from four acute-phase patients, and anti-DV E 2 clones, anti-DV prM 2 clones, and anti-DV NS1 8 clones were derived from five convalescent-phase patients. Methods and results: In the present study, we examined whether these clones cross-reacted with Japanese encephalitis virus (JEV), which belongs to the same virus family. Forty-six of the above-described 99 (46/99) anti-E, 0/8 anti-prM, and 2/4 anti-NS1 HuMAbs from acute-phase, and 0/2 anti-E, 0/2 anti-prM, and 5/8 anti-NS1 HuMAbs from convalescent-phase showed neutralizing activity against JEV. Thus, most of the anti-E and anti-NS1 (but not the anti-prM) antibodies cross-reacted with JEV and neutralized this virus. Interestingly, 3/46 anti-E HuMAbs derived from acute-phase patients and 3/5 anti-NS1 HuMAbs from convalescent-phase patients showed particularly high neutralizing activity against JEV. Consequently, the HuMAbs showing neutralization against JEV mostly consisted of two populations: one was HuMAbs recognizing DV E and showing neutralization activity against all four DV serotypes (complex-type) and the other was HuMAbs recognizing DV NS1 and showing subcomplex-type cross-reaction with DV. Conclusion: Anti-DV E from acute phase (46/99) and anti-DV NS1 (7/12) indicate neutralizing activity against JEV. In particular, three of 46 anti-DV E clones from acute phase and three of five anti-NS1 clones from convalescent phase showed strong neutralizing activity against JEV. Keywords: Dengue virus, Japanese encephalitis virus, viral neutralization, human monoclonal antibody, envelope, nonstructural protein 1

Published
2013

9. The impact of local surface changes in Borneo on atmospheric composition at wider spatial scales: coastal processes, land-use change and air quality

Author

Pyle, J. A., Warwick, N. J., Harris, N. R. P., Abas, Mohd Radzi, Archibald, A. T., Ashfold, M. J., Ashworth, K., Barkley, Michael P., Carver, G. D., Chance, K., Dorsey, J. R., Fowler, D., Gonzi, S., Gostlow, B., Hewitt, C. N., Kurosu, T. P., Lee, J. D., Langford, S. B., Mills, G., Moller, S., MacKenzie, A. R., Manning, A. J., Misztal, P., Nadzir, Mohd Shahrul Mohd, Nemitz, E., Newton, H. M., O'Brien, L. M., Ong, Simon, Oram, D., Palmer, P. I., Peng, Leong Kok, Phang, Siew Moi, Pike, R., Pugh, T. A. M., Rahman, Noorsaadah Abdul, Robinson, A. D., Sentian, J., Samah, Azizan Abu, Skiba, U., Ung, Huan Eng, Yong, Sei Eng, and Young, P. J.

Published
2011

10. Limited cross-reactivity of mouse monoclonal antibodies against Dengue virus capsid protein among four serotypes

Author

Noda M, Masrinoul P, Punkum C, Pipattanaboon C, Ramasoota P, Setthapramote C, Sasaki T, Sasayama M, Yamashita A, Kurosu T, Ikuta K, and Okabayashi T

Subjects
Medicine (General), R5-920
Abstract

Megumi Noda,1 Promsin Masrinoul,1 Chaweewan Punkum,1 Chonlatip Pipattanaboon,2,3 Pongrama Ramasoota,2,4 Chayanee Setthapramote,2,3 Tadahiro Sasaki,6 Mikiko Sasayama,1 Akifumi Yamashita,1,5 Takeshi Kurosu,6 Kazuyoshi Ikuta,6 Tamaki Okabayashi11Mahidol-Osaka Center for Infectious Diseases, 2Center of Excellence for Antibody Research, 3Department of Microbiology and Immunology, 4Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Ratchathewi, Bangkok, Thailand; 5Graduate School of Life Science, Tohoku University, Sendai, Miyagi, 6Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, JapanBackground: Dengue illness is one of the important mosquito-borne viral diseases in tropical and subtropical regions. Four serotypes of dengue virus (DENV-1, DENV-2, DENV-3, and DENV-4) are classified in the Flavivirus genus of the family Flaviviridae. We prepared monoclonal antibodies against DENV capsid protein from mice immunized with DENV-2 and determined the cross-reactivity with each serotype of DENV and Japanese encephalitis virus.Methods and results: To clarify the relationship between the cross-reactivity of monoclonal antibodies and the diversity of these viruses, we examined the situations of flaviviruses by analyses of phylogenetic trees. Among a total of 60 prepared monoclonal antibodies specific for DENV, five monoclonal antibodies stained the nuclei of infected cells and were found to be specific to the capsid protein. Three were specific to DENV-2, while the other two were cross-reactive with DENV-2 and DENV-4. No monoclonal antibodies were cross-reactive with all four serotypes. Phylogenetic analysis of DENV amino acid sequences of the capsid protein revealed that DENV-2 and DENV-4 were clustered in the same branch, while DENV-1 and DENV-3 were clustered in the other branch. However, these classifications of the capsid protein were different from those of the envelope and nonstructural 1 proteins. Phylogenetic distances between the four serotypes of DENV were as different as those of other flaviviruses, such as Japanese encephalitis virus and West Nile virus. Large variations in the DENV serotypes were comparable with the differences between species of flavivirus. Furthermore, the diversity of flavivirus capsid protein was much greater than that of envelope and nonstructural 1 proteins.Conclusion: In this study, we produced specific monoclonal antibodies that can be used to detect DENV-2 capsid protein, but not a cross-reactive one with all serotypes of DENV capsid protein. The high diversity of the DENV capsid protein sequence by phylogenetic analysis supported the low cross-reactivity of monoclonal antibodies against DENV capsid protein.Keywords: Dengue virus, capsid protein, monoclonal antibody, cross-reactivity

Published
2012

15. Field emission from amorphous carbon films grown by electrochemical deposition using methanol liquid

Author

Kiyota, H., Higashi, M., Kurosu, T., and Iida, M.

Subjects
Methanol -- Atomic properties, Amorphous semiconductors -- Atomic properties, Raman spectroscopy -- Usage, Scanning microscopy -- Usage, Dielectric films -- Design and construction, Dielectric films -- Electric properties, Thin films -- Design and construction, Thin films -- Electric properties, Physics
Abstract

The field emission from an amorphous carbon (a-C) film grown by electrochemical deposition on specific substrates like Ti and Al immersed in methanol, is analyzed. The interface barrier is reduced by formation of the Ti interfacial layer, suggesting that the formation of TiC decreases the contact resistance between the substrate and the a-C film, and hence an approach to use carbide formation at the interface is verified as useful to improve the emission properties of a-C films.

Published
2006

19. Analysis of Satellite-Derived Arctic Tropospheric BrO Columns in Conjunction with Aircraft Measurements During ARCTAS and ARCPAC

Author

Choi, S, Wang, Y, Salawitch, R. J, Canty, T, Joiner, J, Zeng, T, Kurosu, T. P, Chance, K, Richter, A, Huey, L. G, Liao, J, Neuman, J. A, Nowak, J. B, Dibb, J. E, Weinheimer, A. J, Diskin, G, Ryerson, T. B, da Silva, A, Curry, J, Kinnison, D, Tilmes, S, and Levelt, P. F

Subjects
Geophysics
Abstract

We derive tropospheric column BrO during the ARCTAS and ARCPAC field campaigns in spring 2008 using retrievals of total column BrO from the satellite UV nadir sensors OMI and GOME-2 using a radiative transfer model and stratospheric column BrO from a photochemical simulation. We conduct a comprehensive comparison of satellite-derived tropospheric BrO column to aircraft in-situ observations ofBrO and related species. The aircraft profiles reveal that tropospheric BrO, when present during April 2008, was distributed over a broad range of altitudes rather than being confined to the planetary boundary layer (PBL). Perturbations to the total column resulting from tropospheric BrO are the same magnitude as perturbations due to longitudinal variations in the stratospheric component, so proper accounting of the stratospheric signal is essential for accurate determination of satellite-derived tropospheric BrO. We find reasonably good agreement between satellite-derived tropospheric BrO and columns found using aircraft in-situ BrO profiles, particularly when satellite radiances were obtained over bright surfaces (albedo> 0.7), for solar zenith angle < 80 and clear sky conditions. The rapid activation of BrO due to surface processes (the bromine explosion) is apparent in both the OMI and GOME-2 based tropospheric columns. The wide orbital swath of OMI allows examination of the evolution of tropospheric BrO on about hourly time intervals near the pole. Low surface pressure, strong wind, and high PBL height are associated with an observed BrO activation event, supporting the notion of bromine activation by high winds over snow.

Published
2012

21. The Unique OMI HCHO/NO2 Feature During the 2008 Beijing Summer Olympics: Implications for Ozone Production Sensitivity

Author

Witte, J. C, Duncan, B. N, Douglass, A. R, Kurosu, T. P, Chance, K, and Retscher, C

Subjects
Environment Pollution
Abstract

In preparation of the Beijing Summer Olympic and Paralympics Games, strict controls were imposed between July and September 2008 on motor vehicle traffic and industrial emissions to improve air quality for the competitors. We assessed chemical sensitivity of ozone production to these controls using Ozone Monitoring Instrument (OMI) column measurements of formaldehyde (HCHO) and nitrogen dioxide (NO2), where their ratio serves as a proxy for the sensitivity. During the emission controls, HCHO/NO2 increased and indicated a NOx-limited regime, in contrast to the same period in the preceding three years when the ratio indicates volatile organic carbon (VOC)-limited and mixed NOx-VOC-limited regimes. After the emission controls were lifted, observed NO2 and HCHO/NO2 returned to their previous values. The 2005-2008 OMI record shows that this transition in regimes was unique as ozone production in Beijing was rarely NOx-limited. OMI measured summertime increases in HCHO of around 13% in 2008 compared to prior years, the same time period during which MODIS vegetation indices increased. The OMI HCHO increase may be due to higher biogenic emissions of HCHO precursors, associated with Beijing's greening initiative for the Olympics. However, NO2 and HCHO were also found to be well-correlated during the summer months. This indicates an anthropogenic VOC contribution from vehicle emissions to OMI HCHO and is a plausible explanation for the relative HCHO minimum observed in August 2008, concurrent with a minimum in traffic emissions. We calculated positive trends in 2005-2008 OMI HCHO and NO2 of about +1 x 10(exp 14) Molec/ square M-2 and +3 x 10(exp 13) molec CM-2 per month, respectively. The positive trend in NO2 may be an indicator of increasing vehicular traffic since 2005, while the positive trend in HCHO may be due to a combined increase in anthropogenic and biogenic emissions since 2005.

Published
2010

24. Satellite Mapping of Rain-Induced Nitric Oxide Emissions from Soils

Author

Jaegle, L, Martin, R. V, Chance, K, Steinberger, L, Kurosu, T. P, Jacob, D. J, Modi, A. I, Yoboue, V, Sigha-Nkamdjou, L, and Galy-Lacaux, C

Subjects
Meteorology And Climatology
Abstract

We use space-based observations of NO2 columns from the Global Ozone Monitoring Experiment (GOME) to map the spatial and seasonal variations of NOx emissions over Africa during 2000. The GOME observations show not only enhanced tropospheric NO2 columns from biomass burning during the dry season but also comparable enhancements from soil emissions during the rainy season over the Sahel. These soil emissions occur in strong pulses lasting 1-3 weeks following the onset of rain, and affect 3 million sq km of semiarid sub-Saharan savanna. Surface observations of NO2 from the International Global Atmospheric Chemistry (IGAC)/Deposition of Biochemically Important Trace Species (DEBITS)/Africa (IDAF) network over West Africa provide further evidence for a strong role for microbial soil sources. By combining inverse modeling of GOME NO2 columns with space-based observations of fires, we estimate that soils contribute 3.3+/-1.8 TgN/year, similar to the biomass burning source (3.8+/-2.1 TgN/year), and thus account for 40% of surface NO(x) emissions over Africa. Extrapolating to all the tropics, we estimate a 7.3 TgN/year biogenic soil source, which is a factor of 2 larger compared to model-based inventories but agrees with observation-based inventories. These large soil NO(x) emissions are likely to significantly contribute to the ozone enhancement originating from tropical Africa.

Published
2004
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25. Tropospheric Formaldehyde Measurements from the ESA GOME Instrument

Author

Chance, K, Spurr, R. J. D, Kurosu, T. P, Palmer, P. I, Martin, R. V, Fiore, A, Li, Q, and Jacob, D. J

Subjects
Environment Pollution
Abstract

The Global Ozone Monitoring Experiment (GOME) was launched on the European Space Agency's ERS-2 satellite on April 20, 1995. GOME measures the Earth's atmosphere in the nadir geometry, using a set of spectrometers that cover the UV and visible (240-790 nm) at moderate resolution (0.2 nm in the UV, 0.4 nm in the visible), employing silicon diode array detectors. GOME takes some 30,000 spectra per day, obtaining full global coverage in three days. We directly fit GOME radiance spectra using nonlinear least-squares analysis to obtain column amounts of several trace species with significant tropospheric concentrations, including ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), and formaldehyde (HCHO). Measurements of HCHO due to biogenic activity in the troposphere are presented here.

Published
2001

27. Validation of Ozone Monitoring Instrument (OMI) ozone profiles and stratospheric ozone columns with Microwave Limb Sounder (MLS) measurements

Author

Liu, X., Bhartia, P. K., Kelly Chance, Froidevaux, L., Spurr, R. J. D., and Kurosu, T. P.

Subjects
lcsh:Chemistry, lcsh:QD1-999, lcsh:Physics, lcsh:QC1-999
Abstract

We validate OMI ozone profiles between 0.22–215 hPa and stratospheric ozone columns down to 215 hPa (SOC215) against v2.2 MLS data from 2006. The validation demonstrates convincingly that SOC can be derived accurately from OMI data alone, with errors comparable to or smaller than those from current MLS retrievals, and it demonstrates implicitly that tropospheric ozone column can be retrieved accurately from OMI or similar nadir-viewing ultraviolet measurements alone. The global mean biases are within 2.5% above 100 hPa and 5–10% below 100 hPa; the standard deviations (1σ) are 3.5–5% between 1–50 hPa, 6–9% above 1 hPa and 8–15% below; 50 hPa. OMI shows some latitude and solar zenith angle dependent biases, but the mean biases are mostly within 5% and the standard deviations are mostly within 2–5% except for low altitudes and high latitudes. The excellent agreement with MLS data shows that OMI retrievals can be used to augment the validation of MLS and other stratospheric ozone measurements made with even higher vertical resolution than that for OMI. OMI SOC215 shows a small bias of −0.6% with a standard deviation of 2.8%. When compared as a function of latitude and solar zenith angle, the mean biases are within 2% and the standard deviations range from 2.1 to 3.4%. Assuming 2% precision for MLS SOC215, we deduce that the upper limits of random-noise and smoothing errors for OMI SOC215 range from 0.6% in the southern tropics to 2.8% at northern middle latitudes.

Published
2010

42. Global satellite analysis of the relation between aerosols and short-lived trace gases

Author

Veefkind, J.P., Boersma, K.F., Wang, J., Kurosu, T., Chance, K., Krotkov, N.A., Levelt, P.F., Veefkind, J.P., Boersma, K.F., Wang, J., Kurosu, T., Chance, K., Krotkov, N.A., and Levelt, P.F.

Abstract

The spatial and temporal correlations between concurrent satellite observations of aerosol optical thickness (AOT) from the Moderate Resolution Imaging Spectroradiometer (MODIS) and tropospheric columns of nitrogen dioxide (NO2), sulfur dioxide (SO2), and formaldehyde (HCHO) from the Ozone Monitoring Instrument (OMI) are used to infer information on the global composition of aerosol particles. When averaging the satellite data over large regions and longer time periods, we find significant correlation between MODIS AOT and OMI trace gas columns for various regions in the world. This shows that these enhanced aerosol and trace gas concentrations originate from common sources, such as fossil fuel combustion, biomass burning, and organic compounds released from the biosphere. This leads us to propose that satellite-inferred AOT to NO2 ratios for regions with comparable photochemical regimes can be used as indicators for the relative regional pollution control of combustion processes. Indeed, satellites observe low AOT to NO2 ratios over the eastern United States and western Europe, and high AOT to NO2 ratios over comparably industrialized regions in eastern Europe and China. Emission databases and OMI SO2 observations over these regions suggest a much stronger sulfur contribution to aerosol formation than over the well-regulated areas of the eastern United States and western Europe. Furthermore, satellite observations show AOT to NO2 ratios are a factor 100 higher over biomass burning regions than over industrialized areas, reflecting the unregulated burning practices with strong primary particle emissions in the tropics compared to the heavily controlled combustion processes in the industrialized Northern Hemisphere. Simulations with a global chemistry transport model (GEOS-Chem) capture most of these variations, although on regional scales significant differences are found. Wintertime aerosol concentrations show strongest correlations with NO2 throughout most of the

Published
2011

43. The impact of local surface changes in Borneo on atmospheric composition at wider spatial scales:coastal processes, land-use change and air quality

Author

Pyle, J. A., Warwick, N. J., Harris, N. R. P., Abas, Mohd Radzi, Archibald, A. T., Ashfold, M. J., Ashworth, Kirsti, Barkley, Michael P., Carver, G. D., Chance, K., Dorsey, J. R., Fowler, D., Gonzi, S., Gostlow, B., Hewitt, C. N., Kurosu, T. P., Lee, J. D., Langford, Ben, Moller, S., Mackenzie, A. R., Manning, A. J., Misztal, P., Nadzir, Mohd Shahrul Mohd, Nemitz, Eiko, Newton, Hannah, O'Brien, L. M., Ong, Simon, Oram, David, Palmer, P. I., Peng, Leong Kok, Phang, Seiw-Moi, Pike, R., Pugh, T. A. M., Rahman, Noorsaadah Abdul, Robinson, A. D., Sentian, Justin, Samah, Azizan Abu, Skiba, U., Ung, Huan Eng, Yong, Sei Eng, Young, P. J., Pyle, J. A., Warwick, N. J., Harris, N. R. P., Abas, Mohd Radzi, Archibald, A. T., Ashfold, M. J., Ashworth, Kirsti, Barkley, Michael P., Carver, G. D., Chance, K., Dorsey, J. R., Fowler, D., Gonzi, S., Gostlow, B., Hewitt, C. N., Kurosu, T. P., Lee, J. D., Langford, Ben, Moller, S., Mackenzie, A. R., Manning, A. J., Misztal, P., Nadzir, Mohd Shahrul Mohd, Nemitz, Eiko, Newton, Hannah, O'Brien, L. M., Ong, Simon, Oram, David, Palmer, P. I., Peng, Leong Kok, Phang, Seiw-Moi, Pike, R., Pugh, T. A. M., Rahman, Noorsaadah Abdul, Robinson, A. D., Sentian, Justin, Samah, Azizan Abu, Skiba, U., Ung, Huan Eng, Yong, Sei Eng, and Young, P. J.

Abstract

We present results from the OP3 campaign in Sabah during 2008 that allowus to study the impact of local emission changes over Borneo on atmospheric composition at the regional and wider scale. OP3 constituent data provide an important constraint on model performance. Treatment of boundary layer processes is highlighted as an important area of model uncertainty. Model studies of land-use change confirm earlier work, indicating that further changes to intensive oil palm agriculture in South East Asia, and the tropics in general, could have important impacts on air quality, with the biggest factor being the concomitant changes in NOx emissions. With the model scenarios used here, local increases in ozone of around 50 per cent could occur. We also report measurements of short-lived brominated compounds around Sabah suggesting that oceanic (and, especially, coastal) emission sources dominate locally. The concentration of bromine in short-lived halocarbons measured at the surface during OP3 amounted to about 7 ppt, setting an upper limit on the amount of these species that can reach the lower stratosphere.

Published
2011

45. easurements of atmospheric bromine monoxide at 80N during spring 2008

Author

Adams, C., Fraser, A., Strong, K., Park, D., McLinden, C. A., Chance, K., Kurosu, T., Schofield, Robyn, Adams, C., Fraser, A., Strong, K., Park, D., McLinden, C. A., Chance, K., Kurosu, T., and Schofield, Robyn

Abstract

Despite its low concentrations in the atmosphere, bromine monoxide (BrO) accounts for up to half of springtime catalytic ozone depletion in the stratosphere. In the troposphere, large quantities of BrO can appear suddenly and linger for several days. These bromine explosions have been linked to mercury deposition in the Arctic.Retrieval of BrO is difficult and measurements of bromine species at high latitudes are scarce. Therefore, there are large uncertainties in our knowledge of the amount of bromine in the atmosphere. In order to improve this situation, we measured BrO columns with two ground-based UV-visible spectrometers at the Polar Environment Atmospheric Research Laboratory (PEARL) in Eureka, Nunavut, Canada (80oN, 86oW) in spring 2008. This research is an integral part the larger CANDAC (Canadian Network for the Detection of Atmospheric Change) project at PEARL to study Arctic atmospheric processes through 2007-2009, the International Polar Year (IPY), and beyond.We will discuss the techniques and challenges for ground-based BrO measurements. Furthermore, we will discuss comparisons between the ground-based measurements of BrO above Eureka and those made by the OSIRIS and OMI satellite instruments, distinguishing between tropospheric and stratospheric BrO concentrations.

Published
2009

46. Ground-based BrO measurements above Eureka, Nunavut during spring 2008

Author

Adams, C., Fraser, A., Strong, K., Chance, K., Kurosu, T., Schofield, Robyn, Adams, C., Fraser, A., Strong, K., Chance, K., Kurosu, T., and Schofield, Robyn

Abstract

Because measurements of bromine at high latitudes are scarce, the current understanding of bromine chemistry is largely based on model calculations. In order to help quantify the amount of bromine in the atmosphere, we measured BrO columns with two ground-based UV-visible spectrometers at the Polar Environment Atmospheric Research Laboratory (PEARL) in Eureka, Nunavut, Canada (80oN, 86oW) in spring 2008. One of these instruments, the UT-GBS (University of Toronto Ground-Based Spectrometer), has been deployed at Eureka during polar sunrise since 1999. The other instrument, the PEARL-GBS (PEARL Ground-Based Spectrometer), was installed permanently in Eureka in August 2006 for year-round operation.The small signal and large diurnal variation of BrO are challenges for ground-based BrO retrievals. With zenith-sky measurements, we can retrieve vertical column densities of BrO, which are primarily sensitive to the stratosphere. We will discuss different methods for these retrievals and will compare our ground-based BrO vertical column density measurements with Ozone Monitoring Instrument on board the NASA Earth Observing System Aura satellite. Additionally, we are working on techniques to retrieve tropospheric partial columns of BrO using a combination of direct-sun measurements and zenith-sky measurements. We will discuss the status of these retrievals and future plans for tropospheric BrO measurements at Eureka.

Published
2009

49. Characteristics of tropospheric ozone depletion events in the Arctic spring: analysis of the ARCTAS, ARCPAC, and ARCIONS measurements and satellite BrO observations

Author

Koo, J.-H., primary, Wang, Y., additional, Kurosu, T. P., additional, Chance, K., additional, Rozanov, A., additional, Richter, A., additional, Oltmans, S. J., additional, Thompson, A. M., additional, Hair, J. W., additional, Fenn, M. A., additional, Weinheimer, A. J., additional, Ryerson, T. B., additional, Solberg, S., additional, Huey, L. G., additional, Liao, J., additional, Dibb, J. E., additional, Neuman, J. A., additional, Nowak, J. B., additional, Pierce, R. B., additional, Natarajan, M., additional, and Al-Saadi, J., additional

Published
2012
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