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In birds, incubation‐related behaviors and brood patch formation are influenced by hormonal regulation such as prolactin secretion. Brood patch provides efficient heat transfer between the incubating parent and the developing embryo in the egg. Importantly, several environmental contaminants are already known to have adverse effects on avian reproduction. However, relatively little is known about the effect of contaminants on incubation temperature (Tinc) in wild birds. By using temperature thermistors placed into artificial eggs, we investigated whether the most contaminated parent birds are less able to provide appropriate egg warming and thus less committed to incubating their clutch. Specifically, we investigated the relationships among 3 groups of contaminants (organochlorines, perfluoroalkyl substances [PFASs], and mercury [Hg]) with Tinc and also with prolactin concentrations and brood patch size in incubating Arctic black‐legged kittiwakes (Rissa tridactyla). Our results reveal that among the organochlorines considered, only blood levels of oxychlordane, the main metabolite of chlordane, a banned pesticide, were negatively related to the minimum incubation temperature in male kittiwakes. Levels of PFASs and Hg were unrelated to Tinc in kittiwakes. Moreover, our study suggests a possible underlying mechanism: since we reported a significant and negative association between blood oxychlordane concentrations and the size of the brood patch in males. Finally, this reduced Tinc in the most oxychlordane‐contaminated kittiwakes was associated with a lower egg hatching probability.
Pergamon Press
2018
2018
2018
2018
Zurich statement on future actions on per-and polyfluoroalkyl substances (PFASs)
Per- and polyfluoroalkyl substances (PFASs) are man-made chemicals that contain at least one perfluoroalkyl moiety, –CnF2n–. To date, over 4,000 unique PFASs have been used in technical applications and consumer products, and some of them have been detected globally in human and wildlife biomonitoring studies. Because of their extraordinary persistence, human and environmental exposure to PFASs will be a long-term source of concern. Some PFASs such as perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) have been investigated extensively and thus regulated, but for many other PFASs, knowledge about their current uses and hazards is still very limited or missing entirely. To address this problem and prepare an action plan for the assessment and management of PFASs in the coming years, a group of more than 50 international scientists and regulators held a two-day workshop in November, 2017. The group identified both the respective needs of and common goals shared by the scientific and the policy communities, made recommendations for cooperative actions, and outlined how the science–policy interface regarding PFASs can be strengthened using new approaches for assessing and managing highly persistent chemicals such as PFASs.
2018
Taylor & Francis
2018
Monitoring of long-range transported air pollutants in Norway, Annual Report 2017
This report presents results from the monitoring of atmospheric composition and deposition of air pollution in 2017, and focuses on main components in air and precipitation, particulate and gaseous phase of inorganic constituents, particulate carbonaceous matter, ground level ozone and particulate matter. The concentration levels were generally low in 2017 compared to previous years.
NILU
2018
2018
2018
This report presents VOC measurements carried out during 2016 at EMEP monitoring sites. In total, 19 sites reported VOC data from EMEP VOC sites this year. Some of the data sets are considered preliminary and are not included in the report.
The monitoring of NMHC (non-methane hydrocarbons) has become more diverse with time in terms of instrumentation. Starting in the early 1990s with standardized methods based on manual sampling in steel canisters with subsequent analyses at the lab, the methods now consist of a variety of instruments and measurement principles, including automated continuous monitors and manual flask samples. For oxygenated VOCs (OVOCs), sampling in DNPH-tubes with subsequent lab-analyses is still the only method in use at EMEP sites.
Within the EU infrastructure project ACTRIS-2, data quality issues related to measurements of VOC have been an important topic. Many of the institutions providing VOC data to EMEP have participated in the ACTRIS-2 project, either as formal partners or on a voluntary basis. Participation in ACTRIS-2 has meant an extensive effort with data checking including detailed discussions between the ACTRIS community and individual participants. There is no doubt that this extensive effort has benefited the EMEP program and has led to improved data quality in general.
Comparison between median levels in 2016 compared to the medians of the previous 10-years period, revealed a similar north-to-south pattern for several species.
Changes in instrumentation, procedures, station network etc. during the last two decades make it difficult to provide a rigorous and pan-European assessment of long-term trends of the observed VOCs. In this report we have estimated the long-term trends in NMHC over the 2000-2016 period at six selected sites by two independent statistical methods. These estimates indicate marked differences in the trends for the individual species. Small or non-significant trends were found for ethane over this period followed by propane which also showed fairly small reductions. On the other hand, components linked to road traffic (ethene, ethyne and toluene) showed the strongest drop in mean concentrations, up to 60-80% at some stations. The trend in n-butane was between these two groups of species with an estimated drop in the annual mean concentration of 20-40% over the 2000-2016 period
NILU
2018
Monitoring of the atmospheric ozone layer and natural ultraviolet radiation: Annual report 2017.
This report summarizes the results from the Norwegian monitoring programme on stratospheric ozone and UV radiation measurements. The ozone layer has been measured at three locations since 1979: in Oslo, Tromsø/Andøya and Ny-Ålesund. The UV measurements started in 1995. The results show that there was a significant decrease in stratospheric ozone above Norway between 1979 and 1997. After that the ozone layer stabilized at a level ~2% below pre-1980 level. There are large inter-annual variations and in 2017 there were relatively low values at all the three Norwegian stations during the winter. However, the ozone situation normalized towards the end of spring.
NILU
2018
2018
The UK Toxic Organic Micro Pollutants (TOMPs) Network, which has operated since 1991, collects ambient air samples at six urban, rural, and semi-rural sites across England and Scotland, using high-volume active air samplers [1]. Furthermore, in 1994, a latitudinal sampling transect from the south of England to the north of Norway was established with eleven sampling sites, mainly in remote locations, using Semi-Permeable Membrane Devices (SPMDs) as passive air samplers [2]. Both networks provide continuous, long-term ambient air trend data for a range of Persistent Organic Pollutants (POPs), including PCBs and PBDEs, and have helped demonstrating a decline in POPs air concentrations over the last three decades. However, in recent years no further significant declines have been observed. SumPCB and SumPBDE levels in the UK are lowest at the rural sites and highest for the urban sites (TOMPs), and they generally decrease from the south of England to the north of Norway (UK/Norway) in line with expectations. Higher values at less remote sites and sites downwind from population centres show that POPs concentrations may still mainly be influenced by primary emissions. Concentrations at semi-rural sites lie between rural and urban sites; however, they can exceed the latter in some years. This can probably be attributed to short-term local effects. The data from the TOMPs network shows that concentrations of PCBs are higher in warmer than in colder months, while the seasonal patterns are less uniform for PBDEs.
2018
2018
2018
2018
Seasonality of aerosol optical properties in the Arctic
Given the sensitivity of the Arctic climate to short-lived climate forcers, long-term in situ surface measurements of aerosol parameters are useful in gaining insight into the magnitude and variability of these climate forcings. Seasonality of aerosol optical properties – including the aerosol light-scattering coefficient, absorption coefficient, single-scattering albedo, scattering Ångström exponent, and asymmetry parameter – are presented for six monitoring sites throughout the Arctic: Alert, Canada; Barrow, USA; Pallas, Finland; Summit, Greenland; Tiksi, Russia; and Zeppelin Mountain, Ny-Ålesund, Svalbard, Norway. Results show annual variability in all parameters, though the seasonality of each aerosol optical property varies from site to site. There is a large diversity in magnitude and variability of scattering coefficient at all sites, reflecting differences in aerosol source, transport, and removal at different locations throughout the Arctic. Of the Arctic sites, the highest annual mean scattering coefficient is measured at Tiksi (12.47Mm−1), and the lowest annual mean scattering coefficient is measured at Summit (1.74Mm−1). At most sites, aerosol absorption peaks in the winter and spring, and has a minimum throughout the Arctic in the summer, indicative of the Arctic haze phenomenon; however, nuanced variations in seasonalities suggest that this phenomenon is not identically observed in all regions of the Arctic. The highest annual mean absorption coefficient is measured at Pallas (0.48Mm−1), and Summit has the lowest annual mean absorption coefficient (0.12Mm−1). At the Arctic monitoring stations analyzed here, mean annual single-scattering albedo ranges from 0.909 (at Pallas) to 0.960 (at Barrow), the mean annual scattering Ångström exponent ranges from 1.04 (at Barrow) to 1.80 (at Summit), and the mean asymmetry parameter ranges from 0.57 (at Alert) to 0.75 (at Summit). Systematic variability of aerosol optical properties in the Arctic supports the notion that the sites presented here measure a variety of aerosol populations, which also experience different removal mechanisms. A robust conclusion from the seasonal cycles presented is that the Arctic cannot be treated as one common and uniform environment but rather is a region with ample spatiotemporal variability in aerosols. This notion is important in considering the design or aerosol monitoring networks in the region and is important for informing climate models to better represent short-lived aerosol climate forcers in order to yield more accurate climate predictions for the Arctic.
2018