Ambient Nitro-Aromatic Compounds – Biomass Burning versus Secondary Formation in rural China

Nitro-aromatic compounds (NACs) were measured hourly at a rural site in China during wintertime to monitor the changes due to local and regional impacts of biomass burning (BB). Concurrent and continuous measurements of the concentrations of 16 NACs in the gas and particle phases were performed with a time-of-flight chemical ionization mass spectrometer (CIMS) equipped with a Filter Inlet for Gas and Aerosol (FIGAERO) unit using iodide as the reagent ion. NACs accounted for

Indian megacities as localities of environmental vulnerability from air quality perspective

Large proportions of the Indian population live in megacities (e.g., Delhi, Mumbai and Kolkata), which are vibrant centers of economic opportunities and offering better quality of social life. Due to increasing migration to these cities, Indian megacities are constantly expanding, which subsequently leads to strain on the environment with a range of impacts at local, regional and global levels. During the last few decades the anthropogenic emissions of greenhouse gases (GHGs) and other air pollutants have increased substantially, resulting in worsening ambient air quality of these cities. With respect to time span the concern over air pollutants has also changed in Indian megacities. Concern over particulate matter, black carbon, NOx and ozone has heightened recently due to their local and regional impacts on air quality and environmental (including public) health and also because they contribute to global climate change. Although authorities have implemented several measures to reduce air pollution and its impacts in Indian megacities, much more is yet to be done to improve their ambient air quality. This paper focuses on major air pollution and GHGs emission issues in Indian megacities and associated problems within the framework of their role in environmental vulnerability.

Modeling the impacts of biomass burning on air quality in and around Mexico City

The local and regional impacts of open fires and trash burning on ground-level ozone (O3) and fine carbonaceous aerosols in the Mexico City Metropolitan Area (MCMA) and surrounding region during two high fire periods in March 2006 have been evaluated using WRF-CHEM model. The model captured reasonably well the measurement-derived magnitude and temporal variation of the biomass burning organic aerosol (BBOA), and the simulated impacts of open fires on organic aerosol (OA) were consistent with many observation-based estimates. We did not detect significant effects of open fires and trash burning on surface O3 concentrations in the MCMA and surrounding region. In contrast, they had important influences on OA and elemental carbon (EC), increasing primary OA (POA) by ~60%, secondary OA (SOA) by ~22%, total OA (TOA = POA + SOA) by ~33%, and EC by ~22%, on both the local (urban) and regional scales. Although the emissions of trash burning are substantially lower than those from open fires, trash burning made slightly smaller but comparable contributions to OA as open fires did, and exerted an even higher influence on EC. Of the ~22% enhancement in SOA concentrations (equivalent to a ~15% increase in TOA) simulated, about two third was attributed to the open fires and one-third to the trash burning. On the annual basis and taking the biofuel use emissions into consideration, we estimated that open fires, trash burning and biofuel use together contributed about 60% to the loading of POA, 30% to SOA, and 25% to EC in both the MCMA and its surrounding region, of which the open fires and trash burning contributed about 35% to POA, 18% to SOA, and 15% to EC. The estimates of biomass burning impacts in this study may contain considerable uncertainties due to the uncertainties in their emission estimates in magnitude, temporal and spatial distribution, extrapolations and the nature of spot comparison. More observation and modeling studies are needed to accurately assess the impacts of biomass burning on tropospheric chemistry, regional and global air quality, and climate change.

Modeling the impacts of biomass burning on air quality in and around Mexico City

The local and regional impacts of open fires and trash burning on ground-level ozone (O3) and fine carbonaceous aerosols in the Mexico City Metropolitan Area (MCMA) and surrounding region during two high fire periods in March 2006 have been evaluated using WRF-CHEM model. The model captured reasonably well the measurement-derived magnitude and temporal variation of the biomass burning organic aerosol (BBOA), and the simulated impacts of open fires on organic aerosol (OA) were consistent with many observation-based estimates. We did not detect significant effects of open fires and trash burning on surface O3 concentrations in the MCMA and surrounding region. In contrast, they had important influences on OA and elemental carbon (EC), contributing about 60, 22, 33, and 22% to primary OA (POA), secondary OA (SOA), total OA (TOA), and EC, respectively, on both the local and regional scales. Although the emissions of trash burning are substantially lower than those from open fires, trash burning made slightly smaller but comparable contributions to OA as open fires did, and exerted an even higher influence on EC. SOA formation due to the open fires and trash burning enhanced the OA concentration by about 10 and 5% in the MCMA, respectively. On the annual basis and taking the biofuel use emissions into consideration, we estimated that biomass burning contributed about 60, 30, and 25%, respectively, to the loadings of POA, SOA and EC in both the MCMA and its surrounding region, with about 35, 18, and 15% from open fires and trash burning. The estimates of biomass burning impacts in this study may contain considerable uncertainties due to the uncertainties in their emission estimates, extrapolations and the nature of spot comparison. More observation and modeling studies are needed to accurately assess the impacts of biomass burning on tropospheric chemistry, regional and global air quality, and climate change.

Social and economic perspective on recreational billfish fisheries

At the Second International Billfish Symposium in Kona, it was reported that little was known about the social and economic aspects of recreational billfish fisheries. There was plenty of background, some good questions, but few answers. There had been little history of social science involvement in fisheries management at the time and even less in billfish fisheries. Whether authorized or not, fishery management decisions worldwide are going to be made on the basis of ‘best available’ social and economic understanding. Unfortunately, the values held by many in the billfish angler community are not likelyto be well represented in the mix for various reasons. Research in the USA and in Latin America over the past 13 years hasprovided an understanding of the billfish angler constituency, its commitment to catch and release and support for resource conservation, its local and regional impacts on tourism economies, and its willingness-to-pay above andbeyond trip costs (a measure of user value) in the US Atlantic, Puerto Rico, Costa Rica and Mexico Pacific. Although knowledge of the recreational billfish fishery has improved, comparatively little is known about the social and economic benefits associatedwith commercial (direct and bycatch) billfish fisheries. With little more than dockside prices available in many localities, it is difficult to know their value in comparison with recreational fisheries and the possible trade-offs associated with various management measures. In addition to describing what is still not known, this paper will identify a future research agenda in this area.