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Lin N.-H.,National Central University | Tsay S.-C.,NASA | Maring H.B.,NASA | Yen M.-C.,National Central University | And 36 more authors.
Atmospheric Environment | Year: 2013

By modulating the Earth-atmosphere energy, hydrological and biogeochemical cycles, and affecting regional-to-global weather and climate, biomass burning is recognized as one of the major factors affecting the global carbon cycle. However, few comprehensive and wide-ranging experiments have been conducted to characterize biomass-burning pollutants in Southeast Asia (SEA) or assess their regional impact on meteorology, the hydrological cycle, the radiative budget, or climate change. Recently, BASE-ASIA (Biomass-burning Aerosols in South-East Asia: Smoke Impact Assessment) and the 7-SEAS (7-South-East Asian Studies)/Dongsha Experiment were conducted during the spring seasons of 2006 and 2010 in northern SEA, respectively, to characterize the chemical, physical, and radiative properties of biomass-burning emissions near the source regions, and assess their effects. This paper provides an overview of results from these two campaigns and related studies collected in this special issue, entitled "Observation, modeling and impact studies of biomass burning and pollution in the SE Asian Environment". This volume includes 28 papers, which provide a synopsis of the experiments, regional weather/climate, chemical characterization of biomass-burning aerosols and related pollutants in source and sink regions, the spatial distribution of air toxics (atmospheric mercury and dioxins) in source and remote areas, a characterization of aerosol physical, optical, and radiative properties, as well as modeling and impact studies. These studies, taken together, provide the first relatively complete dataset of aerosol chemistry and physical observations conducted in the source/sink region in the northern SEA, with particular emphasis on the marine boundary layer and lower free troposphere (LFT). The data, analysis and modeling included in these papers advance our present knowledge of source characterization of biomass-burning pollutants near the source regions as well as the physical and chemical processes along transport pathways. In addition, we raise key questions to be addressed by a coming deployment during springtime 2013 in northern SEA, named 7-SEAS/BASELInE (Biomass-burning Aerosols & Stratocumulus Environment: Lifecycles and Interactions Experiment). This campaign will include a synergistic approach for further exploring many key atmospheric processes (e.g., complex aerosol-cloud interactions) and impacts of biomass burning on the surface-atmosphere energy budgets during the lifecycles of biomass-burning emissions. © 2013 The Authors.

Atwood S.A.,Colorado State University | Reid J.S.,U.S. Navy | Kreidenweis S.M.,Colorado State University | Cliff S.S.,University of California at Davis | And 5 more authors.
Atmospheric Environment | Year: 2013

Large sources of aerosol particles and their precursors are ubiquitous in East Asia. Such sources are known to impact the South China Sea (henceforth SCS), a sometimes heavily polluted region that has been suggested as particularly vulnerable to climate change. To help elucidate springtime aerosol transport into the SCS, an intensive study was performed on the remote Dongsha (aka Pratas) Islands Atoll in spring 2010. As part of this deployment, a Davis Rotating-drum Uniform size-cut Monitor (DRUM) cascade impactor was deployed to collect size-resolved aerosol samples at the surface that were analyzed by X-ray fluorescence for concentrations of selected elements. HYSPLIT backtrajectories indicated that the transport of aerosol observed at the surface at Dongsha was occurring primarily from regions generally to the north and east. This observation was consistent with the apparent persistence of pollution and dust aerosol, along with sea salt, in the ground-based dataset. In contrast to the sea-level observations, modeled aerosol transport suggested that the westerly flow aloft (~700hPa) transported smoke-laden air toward the site from regions from the south and west. Measured aerosol optical depth at the site was highest during time periods of modeled heavy smoke loadings aloft. These periods did not coincide with elevated aerosol concentrations at the surface, although the model suggested sporadic mixing of this free-tropospheric aerosol to the surface over the SCS. A biomass burning signature was not clearly identified in the surface aerosol composition data, consistent with this aerosol type remaining primarily aloft and not mixing strongly to the surface during the study. Significant vertical wind shear in the region also supports the idea that different source regions lead to varying aerosol impacts in different vertical layers, and suggests the potential for considerable vertical inhomogeneity in the SCS aerosol environment. © 2012.

Wang S.-H.,National Central University | Wang S.-H.,NASA | Wang S.-H.,The Interdisciplinary Center | Tsay S.-C.,NASA | And 19 more authors.
Atmospheric Environment | Year: 2011

Trans-Pacific Asian dust transport has been well documented, but little is known about dust invasion to the South China Sea (SCS). This study presents the first detailed characterization of dust aerosols transported to the northern SCS. On 21 March 2010, a strong Asian dust storm affected large areas from the Gobi deserts to the West Pacific, including Taiwan and Hong Kong, and was also observed by a comprehensive set of instruments at Dongsha Island, a small island (about 2 km2, 20°42′52" N, 116°43′51" E) in the northern SCS. Aerosol measurements including particle mass concentrations, size distribution, optical properties, hygroscopicity, and vertical profiles help depict the evolution of this dust event. Our results indicate that the dust particles were mixed with anthropogenic and marine aerosols, and transported within 250 m above ground level. The long-range transport of Asian dust to the northern SCS could significantly impact the ecosystems in the region. © 2011 Elsevier Ltd.

Lin Y.-K.,National Taiwan University | Lin Y.-K.,Harvard University | Chang S.-C.,Taiwan Environmental Protection Administration | Chang S.-C.,National Defense Medical Center | And 3 more authors.
Environmental Pollution | Year: 2013

This study reported cumulative 6-day (lag 0-5 days) relative risks (RR) and confidence intervals (CI) of daily outpatient visits for total respiratory disease (RD), asthma, and chronic airway obstruction not otherwise classified (CAO) associated with three ozone metrics (daily 1-h maximum (O3, 1 h max), 8-h average maximum (O3, 8 h max), 24-h average (O3, 24 h avg)), and an alternative oxidant indicator (Ox) in Taipei Metropolitan, using distributed lag non-linear models after controlling for potential confounders. The Ox showed the strongest association with outpatient visits for total RD (RR = 1.10, 95% CI: 1.10, 1.11) and asthma (RR = 1.18, 95% CI: 1.00, 1.39) in the cold season. The O3, 24 h avg appeared to be the optimal ozone metric associating with total RD than O3, 1 h max and O3, 8 h max based on model selection. In conclusion, outpatient visits for total RD associated with ozone vary with ozone metrics, disease and season. © Elsevier Ltd. All rights reserved.

Yang C.-J.,Duke University | Chien H.-C.,Taiwan Environmental Protection Administration
Climate Policy | Year: 2010

Taiwan has not been able to join the existing global climate regime because of its ambiguous international status. The Kyoto Protocol and the restrictive accession rules of the United Nations Framework Convention on Climate Change (UNFCCC) preclude Taiwan's membership. The government of Taiwan is preparing to join the post-2012 multilateral climate regime by building its capacity to regulate greenhouse gases and by setting reduction targets. Taiwan currently contributes about 1% of the total anthropogenic greenhouse gas emissions in the world. It has its share of responsibility in global warming and should be included as part of the solution. Taiwan's participation in the World Health Assembly in 2009 suggests that the People's Republic of China might be willing to accept Taiwan's participation in international treaties as long as membership does not imply statehood. If the post-2012 architecture is designed with flexible accession rules, Taiwan might be able to join despite the unresolved political issues regarding its statehood. The accession rules of the World Trade Organization and the Convention for the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean may provide useful precedents on how to design such flexibility. © 2010 Earthscan.

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