Suchergebnisse

Black carbon (BC) particles are important atmospheric radiative forcing agents and also have a negative effect on human health. In this study, a seven wavelength, dual spot aethalometer, was used to determine the equivalent BC (eBC) concentrations at four locations in Ireland; Killarney, Enniscorthy, Birr and Dublin. The aethalometer data were combined with other measurements and meteorological parameters to determine the sources of the particles observed at the monitoring sites. The mean eBC concentrations measured in Killarney and Enniscorthy were higher than those in Dublin during the winter months, while the concentrations in Birr were only marginally lower. The aethalometer source apportionment model was used to show that domestic solid fuel burning accounted for 61%, 81% and 63% of eBC mass in Killarney, Enniscorthy and Birr respectively. The average diurnal profiles for eBC at these three locations showed a minor peak during morning hours attributed to traffic and a very large peak during the evening due to solid fuel burning. Results from two years of continuous measurements at an urban background location in Dublin, showed a strong seasonal variation in eBC. Higher concentrations were measured during winter due to solid fuel burning, which accounted for 57% of eBC during the winter of 2016/2017, and 50% during the winter of 2017/2018. The diurnal profile for Dublin during winter was similar to that observed at the other three sites. During summer, eBC levels were much lower and dominated by traffic emissions. The parameters used in the source apportionment model were explored and site-specific absorption Ångström exponents (α) and Mass Absorption Cross-section (MAC) values were also derived to provide an indication of the different aerosol properties at each location. The results of the source apportionment at all four sites correlate strongly with those from other instruments deployed during the campaigns. The BC levels recorded in Dublin were compared to historical measurements of black smoke in Dublin, Belfast, London and Paris, from 1963 to 2003. Large decreases in BS concentrations (over 90%) have been observed in each city and are related to legislative changes introduced in each jurisdiction over the decades. Overall, this work has highlighted the ability of the aethalometer to measure eBC concentrations in real-time and derive contributions from both solid fuel burning and traffic emissions.

1. Marine legislation, the key means by which the conservation of marine biodiversity is achieved, has been developing since the 1960s. In recent decades, an increasing focus on 'holistic' policy development is evident, compared with earlier 'piecemeal' sectoral approaches. Important marine legislative tools being used in the United Kingdom, and internationally, include the designation of marine protected areas and the Marine Strategy Framework Directive (MSFD) with its aim of meeting 'Good Environmental Status' (GES) for European seas by 2020. 2. There is growing evidence of climate change impacts on marine biodiversity, which may compromise the effectiveness of any legislation intended to promote sustainable marine resource management. 3. A review of key marine biodiversity legislation relevant to the UK shows climate change was not considered in the drafting of much early legislation. Despite the huge increase in knowledge of climate change impacts in recent decades, legislation is still limited in how it takes these impacts into account. There is scope, however, to account for climate change in implementing much of the legislation through (a) existing references to environmental variability; (b) review cycles; and (c) secondary legislation and complementary policy development. 4. For legislation relating to marine protected areas (e.g. the EC Habitats and Birds Directives), climate change has generally not been considered in the site-designation process, or for ongoing management, with the exception of the Marine (Scotland) Act. Given that changing environmental conditions (e.g. rising temperatures and ocean acidification) directly affect the habitats and species that sites are designated for, how this legislation is used to protect marine biodiversity in a changing climate requires further consideration. 5. Accounting for climate change impacts on marine biodiversity in the development and implementation of legislation is vital to enable timely, adaptive management responses. Marine modelling can play an ...

Over the past few decades, substantial funding has been directed towards improving scientific understanding and management of impacts of climate change in the marine environment. Following concerns that the key messages from these studies were not reaching the public, a comprehensive opinion poll of 10,000 European citizens in 10 countries was conducted to establish levels of awareness, concern, and trust among different demographic groups (by age, gender, proximity to the coast) and nationalities. Citizens exhibited varying levels of self-declared 'informedness' and concern. Citizens from Germany, Italy and Spain claimed to be the most informed on marine climate change issues; those from Czech Republic, Netherlands and Estonia claimed to be least informed. Respondents were least aware of ocean acidification and most aware of melting sea ice, pollution and overfishing. Citizens of Italy suggested that they were generally most concerned about marine climate change issues. Respondents from coastal areas claimed to be both more informed and more concerned than those living inland, as did females and older age groups (54-64 years). European citizens obtain information about climate change in the seas and ocean from different sources, particularly television and the internet. Trust in the various media sources varies among countries and demographic groups. Television is trusted most in Estonia, Germany and Ireland and least in France. The internet is trusted most in Italy, Czech Republic and Estonia, but least in France and the United Kingdom. 18-24 year olds are the biggest users of the internet, but trust this source less than older age groups. Academic scientists or those working for environmental NGOs are trusted more than scientists working for government or industry. Citizens from France are more trusting of industry than any other country polled. In terms of policy actions, most respondents highlighted mitigation measures as opposed to local-scale adaptation. Younger participants prioritised actions associated ...

Airborne black carbon particles are monitored in many networks to quantify its impact on air quality and climate. Given its importance, measurements of black carbon mass concentrations must be conducted with instruments operating in a quality checked and assured conditions to generate reliable and comparable data. According to WMO (World Meteorological Organization) and GAW (Global Atmosphere Watch), intercomparisons against a reference instrument are a crucial part of quality controls in measurement activities (WMO, 2016). The WMO-GAW World Calibration Centre for Aerosol Physics (WCCAP) carried out several instrumental comparison and calibration workshops of absorption photometers in the frame of ACTRIS (European Research Infrastructure for the observation of Aerosol, Clouds and Trace Gases) and the COST Action COLOSSAL (Chemical On-Line cOmpoSition and Source Apportionment of fine aerosoL) in January and June 2019. The experiments were conducted to intercompare filter-based particle light absorption photometers, specifically aethalometers AE33 (Magee Scientific), which are operated by research institutions, universities or governmental entities across Europe. The objective was to investigate the individual performance of 23 instruments and their comparability, using synthetic aerosols in a controlled environment and ambient air from the Leipzig urban background. The methodology and results of the intercomparison are presented in this work. The observed instrument-to-instrument variabilities showed differences that were evaluated, before maintenance activities (average deviation from total least square regression: 1.1 %, range: −6 % to 16 %, for soot measurements; average deviation: 0.3 %, range: −14 % to 19 %, for nigrosin measurements), and after they were carried out (average deviation: 0.4 %, range: −8 % to 14 %, for soot measurements; average deviation: 1.1 %, range: −15 % to 11 %, for nigrosin measurements). The deviations are in most of the cases explained by the filter material, the total particles load on the filter, the performance of the flow systems and previous flow check and calibrations carried out with non-calibrated devices. The results of this intensive intercomparison activity show that relatively small unit-to-unit uncertainties of AE33-based particle light absorbing measurements are possible with functioning instruments. It is crucial to follow the guidelines for maintenance activities and the use of the proper filter tape in the AE33 to assure high quality and comparable BC measurements among international observational networks.