Climate Change Reporting in Great Lakes Region Newspapers: A Comparative Study of the Use of Expert Sources

This study focuses on the use of science sources as experts in news stories about climate change coverage in the Great Lakes region of the US and Canada. We examine, using the hierarchy of influences model, whether the use of scientific sources in climate change coverage may be related to factors such as geographic location, reporting frequency, and authorship, in the prestige press as well as regional and local media. The study found that as many or more non-scientists than scientists are selected as sources regardless of geographic location, reporting frequency, or authorship. However, the study also found that the more stories reporters produce on this topic, the more likely their stories are to use and give prominence to science sources. In addition, the articles included few denier sources, but denier views are more likely to appear in a more prominent location in the articles than supporters when stories are framed as conflict over global warming. These results highlight the need for additional research examining the expertise of climate scientists in news stories to better understand news decision-making in the context of complex scientific reporting.     

The unusual suspects? Perception of underlying causes of anthropogenic climate change in coastal communities in Cambodia and Tanzania

Public perception of the underlying causes of anthropogenic climate change is a complex and subjective issue that is critical to effective risk communication. This issue is important to scientists and policymakers because of the role of individual perceptions in influencing their protective behaviour towards risk (e.g., the adoption of climate risk reduction and mitigation strategies). This cross-sectional study elucidated people's perceptions of the underlying causes of human-induced climate change in coastal communities in Cambodia and Tanzania. The multinomial logistic regression model was based on a geographically and demographically stratified national sample of 3,706 individuals conducted between March and September 2013. The distribution of the fundamental causes of anthropogenic climate change in the pooled sample was deforestation (29%), overpopulation – births and immigration (18%), greenhouse gas emissions (12%), illegal resource extraction (14%), and God's will and transgressing cultural norms (26%). Few people in both countries believed that, the usual suspect, greenhouse gas emission was the fundamental cause of anthropogenic climate change. The number of poor rural residents who indicated that deforestation was the major underlying cause of climate change was approximately three times more than members of the same sub-group who noted that greenhouse gas emissions were the underlying cause of climate change. People who had tertiary education were less likely to consider God's will and transgressing cultural norms as the underlying cause of anthropogenic climate change rather than attributing it to greenhouse gas emissions. Therefore, it is imperative to mainstream climate change into educational curricula in both countries.     

Northern Rivers Ecosystem Initiative: Context and Prevailing Legacy

The Northern River Ecosystem Initiative (NREI), 1997–2004, has provided new scientific knowledge in response to specific recommendations from its predecessor, the Northern River Basins Study (NRBS), 1990–1996. The two initiatives together provide a remarkable body of science which is, and will continue to be, used by resource managers responsible for economic and environmental sustainability in the northern watersheds of Alberta. The NREI focused its investigative efforts on improving our understanding related to ecological considerations of changes in river flow, effect of climate change on flow, ecological responses to pollution and cumulative effects, vulnerability of drinking water quality, and to a lesser degree, wildlife (birds) response to large scale changes within the watersheds. Key findings are briefly presented in this paper and discussed in greater detail in the other NREI papers included in this. Commensurate with the undertakings of NREI, provincial and territorial governments, First Nation and Métis communities, and other administrative organizations such as the Mackenzie River Basin Board, undertook policy, regulatory, and watershed initiatives towards achieving sustainability and providing reliable drinking water quality.     

Geospatial approaches to characterizing agriculture in the Chincoteague Bay Subbasin

Most agricultural information is reported by government sources on a state or county basis. The purpose of this study was to demonstrate use of geospatial data, the 2002 Agricultural Cropland Data Layer (CDL) for the mid-Atlantic region, to characterize agricultural, environmental, and other scientific parameters for the Chincoteague Bay subbasin using geographic information systems. This study demonstrated that agriculture can be characterized accurately on subbasin and subwatershed bases, thus complimenting various assessment technologies. Approximately 28% of the dry land of the subbasin was cropland. Field corn was the largest crop. Soybeans, either singly or double-cropped with wheat, were the second most predominant crop. Although the subbasin is relatively small, cropping practices in the northern part were different from those in the southern portion. Other crops, such as fresh vegetables and vegetables grown for processing, were less than 10% of the total cropland. A conservative approximation of the total pesticide usage in the subbasin in 2002 was over 277,000 lbs of active ingredients. Herbicides represented the most frequently used pesticides in the subbasin, both in number (17) and in total active ingredients (over 261,000 lbs). Ten insecticides predominated in the watershed, while only small quantities of three fungicides were used. Total pesticide usage and intensity were estimated using the CDL. Nutrient inputs to cropland from animal manure, chemical fertilizer, and atmospheric deposition were modeled at over 30 million pounds of nitrogen and over 7 million pounds of phosphorous. Crops under conservation tillage had the largest input of both nutrients.     

Interspecific differences in concentrations and congener profiles of chlorinated and brominated organic pollutants in three insectivorous bird species

We investigated the accumulation of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs) in eggs of three insectivorous bird species, the great tit (Parus major), the Northern lapwing (Vanellus vanellus) and the Mediterranean gull (Larus melanocephalus), near the harbour of Antwerp (Belgium). Our results show that lapwing eggs had the highest median concentrations of PCBs (4358 ng/g lw) and PBDEs (109 ng/g lw). Mediterranean gulls feed during breeding on ground-dwelling invertebrates on agricultural fields, which is reflected in higher OCP concentrations in eggs (1235 ng/g lw). Apart from differences in accumulation, also interspecific differences in contaminant profiles were investigated. Significant differences among species were found in the profile of PCBs, PBDEs and OCPs. These differences could be attributed to differences in diet, behaviour and metabolic capacity. Interestingly, the OCP profile in lapwing eggs deviated extremely from the two other species. In both great tit and Mediterranean gull eggs p,p'-DDE was by far the most important compound, whereas in lapwing eggs hexachlorobenzene, oxychlordane, trans-nonachlor and even p,p'-DDT were relatively more abundant than p,p'-DDE. The high p,p'-DDT/p,p'-DDE ratio has previously been described in lapwings, which suggests that low p,p'-DDE accumulation in eggs might be inherent for this species.     

Bioconcentration of triclosan, methyl-triclosan, and triclocarban in the plants and sediments of a constructed wetland

Constructed wetlands are a potential method for the removal of two pharmaceutical and personal care products from wastewater effluent. Triclosan (TCS; 5-chloro-2-[2,4-dichlorophenoxy]phenol) and triclocarban (TCC; 3,4,4′-trichlorocarbanillide) are antimicrobial agents added to a variety of consumer products whose accumulation patterns in constructed wetlands are poorly understood. Here, we report the accumulation of TCS, its metabolite methyl-triclosan (MTCS; 5-chloro-2-[2,4-dichlorophenoxy]), and TCC in wetland plant tissues and sediments. Three wetland macrophytes: Typha latifolia, Pontederia cordata, and Sagittaria graminea were sampled from a constructed wetland in Denton, Texas, USA. MTCS concentrations were below the method detection limit (MDL) for all species. TCS root tissue concentrations in T. latifolia were significantly greater than root concentrations in P. cordata (mean ± SE in ng g⁻¹: 40.3 ± 11.3 vs. 15.0 ± 1.9, respectively), while for TCC, shoot tissue concentrations in S. graminea were significantly greater than in T. latifolia (22.8 ± 9.3 vs. 9.0 (MDL), respectively). For both TCS and TCC, T. latifolia root tissue concentrations were significantly greater than shoot concentrations (TCS: 40.3 ± 11.3 vs. 17.2 ± 0.2, TCC: 26.0 ± 3.6 vs. 9.0, (MDL)). TCC concentrations in P. cordata roots were significantly greater than in shoots (34.4 ± 5.3 vs. 15.4 ± 2.8, respectively). TCS concentrations in T. latifolia roots and sediments and TCC concentrations in sediments generally decreased from wetland inflow to outflow. To our knowledge, this is the first study documenting species and tissue specific differences in the accumulation of TCS and TCC in plants from an operational constructed wetland. The species specific differences in bioaccumulation suggest TCS and TCC removal from constructed wetlands could be enhanced through targeted plantings.     

Responses of Hybrid Poplar Trees to Sulfur Dioxide Fumigation

This paper verifies the presence of significant interclonal variation in the tolerance of hybrid poplar (Populus deltoides Bartr. cv. Angulata × P. trichocarpa Torr. and Gray) to sulfur dioxide fumigation. Rooted stem cuttings of four hybrid poplar clones were exposed to 5 ppm sulfur dioxide for 0, 3, 6, 9, or 12 hours in controlled environment chambers. Multivariate analyses were made from the shoot growth measurements recorded for 4 weeks before and after fumigation and on the data of foliar injury induced by sulfur dioxide. The following factors were statistically significant in determining growth response and foliar injury: (1) genotype; (2) duration of treatment; and (3) interaction between genotype and hours of fumigation. All partial correlations between foliar injury and subsequent shoot growth were positive and significant. Sufficient genetic variation appears to exist in this Populus hybrid to encourage selection of clones tolerant to short-term exposures of high levels of sulfur dioxide.     

Note On The Use of Law Students as an Air Management Resource

Abstract

In this research, pilot-scale trickle bed biofilter systems have been analyzed to determine their effectiveness in controlling toluene in waste gas streams. These studies evaluated two synthetic microbial attachment media—a monolithic channelized medium and a pelletized ceramic medium. Operational parameters considered included toluene loading, empty bed residence time (EBRT), temperature, and long-term operation. The channelized medium provided 99% removal efficiency for a toluene loading of 0.725 kg COD/m³-day during the initial stages. However, continuous operation resulted in reduced and erratic efficiencies, due to air channeling caused by random plugging. After biomass accumulated within the channels and was subsequently removed by hosing, performance of the channelized medium never regained the previous levels. Similarly, the pelletized medium exhibited consistently good performance until the accumulation of excess biomass in the medium interstices also caused overall performance to deteriorate.

Implementation of a suitable backwashing strategy for biomass control was achieved for the pelletized medium by using full medium fluidization. This strategy permitted long-term operation of the biofilter at a toluene loading of 2.27 kg COD/m³-day and 1 minute EBRT, with efficiencies consistently over 99% and no appreciable back-pressure development between successive periods of backwashing.     

Fibers,Electrostatics, and Filtration: A Review of New Technology

This symposium sponsored by the Fiber Society and the Filtration Society has provided a clear indication that the “black-art” era of filtration has passed or is on its way out. The R & D efforts reviewed here by investigators from diverse disciplines provide evidence that these high efficiency particulate control devices can be made to function not only more consistently at high levels but now with even better control of the fine, health damaging particles. The outstanding improvement in every filtration parameter, reliably attainable by aerosol charging and/or by imposing an electric field on the filter, indicates clearly that fabric filtration has now reached an even higher plateau in particulate control technology.     

Processes Influencing Secondary Aerosol Formation in the San Joaquin Valley during Winter

Abstract

Air quality data collected in the California Regional PM₁₀/PM_2.5 Air Quality Study (CRPAQS) are analyzed to qualitatively assess the processes affecting secondary aerosol formation in the San Joaquin Valley (SJV). This region experiences some of the highest fine particulate matter (PM_2.5) mass concentrations in California (≤188 μg/m³ 24-hr average), and secondary aerosol components (as a group) frequently constitute over half of the fine aerosol mass in winter. The analyses are based on 15 days of high-frequency filter and canister measurements and several months of wintertime continuous gas and aerosol measurements. The phase-partitioning of nitrogen oxide (NO_x)-related nitrogen species and carbonaceous species shows that concentrations of gaseous precursor species are far more abundant than measured secondary aerosol nitrate or estimated secondary organic aerosols. Comparisons of ammonia and nitric acid concentrations indicate that ammonium nitrate formation is limited by the availability of nitric acid rather than ammonia. Time-resolved aerosol nitrate data collected at the surface and on a 90-m tower suggest that both the daytime and nighttime nitric acid formation pathways are active, and entrainment of aerosol nitrate formed aloft at night may explain the spatial homogeneity of nitrate in the SJV. NO_x and volatile organic compound (VOC) emissions plus background O₃ levels are expected to determine NO_x oxidation and nitric acid production rates, which currently control the ammonium nitrate levels in the SJV. Secondary organic aerosol formation is significant in winter, especially in the Fresno urban area. Formation of secondary organic aerosol is more likely limited by the rate of VOC oxidation than the availability of VOC precursors in winter.