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Updating historical global inventories of anthropogenic mercury emissions to air. AMAP Technical Report, no. 3, 2010
2010
Updated trends for atmospheric mercury in the Arctic: 1995–2018
The Arctic region forms a unique environment with specific physical, chemical, and biological processes affecting mercury (Hg) cycles and limited anthropogenic Hg sources. However, historic global emissions and long range atmospheric transport has led to elevated Hg in Arctic wildlife and waterways. Continuous atmospheric Hg measurements, spanning 20 years, and increased monitoring sites has allowed a more comprehensive understanding of how Arctic atmospheric mercury is changing over time. Time-series trend analysis of TGM (Total Gaseous Mercury) in air was performed from 10 circumpolar air monitoring stations, comprising of high-Arctic, and sub-Arctic sites. GOM (gaseous oxidised mercury) and PHg (particulate bound mercury) measurements were also available at 2 high-Arctic sites. Seasonal mean TGM for sub-Arctic sites were lowest during fall ranging from 1.1 ng m−3 Hyytiälä to 1.3 ng m−3, Little Fox Lake. Mean TGM concentrations at high-Arctic sites showed the greatest variability, with highest daily means in spring ranging between 4.2 ng m−3 at Amderma and 2.4 ng m−3 at Zeppelin, largely driven by local chemistry. Annual TGM trend analysis was negative for 8 of the 10 sites. High-Arctic seasonal TGM trends saw smallest decline during summer. Fall trends ranged from −0.8% to −2.6% yr−1. Across the sub-Arctic sites spring showed the largest significant decreases, ranging between −7.7% to −0.36% yr−1, while fall generally had no significant trends. High-Arctic speciation of GOM and PHg at Alert and Zeppelin showed that the timing and composition of atmospheric mercury deposition events are shifting. Alert GOM trends are increasing throughout the year, while PHg trends decreased or not significant. Zeppelin saw the opposite, moving towards increasing PHg and decreasing GOM. Atmospheric mercury trends over the last 20 years indicate that Hg concentrations are decreasing across the Arctic, though not uniformly. This is potentially driven by environmental change, such as plant productivity and sea ice dynamics.
Elsevier
2022
Update on Polar Ozone: Past, Present, and Future. WMO Global Ozone Research and Monitoring Project, Report No. 55
2014
Update of background concentrations over Norway. NILU OR
A methodology for creating a new dataset of estimated background concentrations of NO2, O3, PM10, and PM2.5 that are representative of a typical year over Norway, was developed. The dataset has a spatial resolution of 10 km × 10 km and an hourly temporal resolution. The methodology is based on a spatial mapping component for obtaining information on annual mean background concentrations, and a temporal characterization component, which uses long-term time series of station data to describe the typical development of background concentrations throughout a day and a year. When combined, these two components allow estimates of typical background concentrations at any time of the year at any location in Norway. Whereas the previously used VLUFT method of 1993 only provided spatially constant data at the county level, the new method presented here provides spatially continuous data at a comparatively high spatial resolution. Furthermore, while the previous method only gave a range of constant values that were considered valid throughout the entire year, the new technique provides continuous time series for a typical year at hourly resolution at any location in Norway.
2011
Inert spredning av et enhetsutslipp er kombinert med tidsavhengig luftkjemi for å beregne maksimal belastning I luft og ferskvann for utslipp fra aminabsorberen ved TCM. Beregningene for et worst case viser at maksimal belastning av summen av nitrosaminer og nitraminer er 5 % av anbefalt retningslinje for luftkvalitet. Maksimale konsentrasjoner i ferskvann fra utslippet er fra 13 % til 53 % av retningslinjen avhengig av hvilken absorbent som benyttes og hvilken avgass som renses. Effekten av et "likely case" er estimert. Estimatet viser at luftkonsentrasjonene blir en faktor 3 lavere enn worst case. Ferskvannkonsentrasjonene blir en faktor fra 10 til 20 lavere enn worst case avhengig av hvilken absorbent som benyttes.
2011
Inert spredning av et enhetsutslipp er kombinert med tidsavhengig luftkjemi for å beregne maksimal belastning I luft og ferskvann for utslipp fra aminabsorberen ved TCM. Beregningene for et likely case viser at maksimal belastning av summen av nitrosaminer og nitraminer er 2 % av anbefalt retningslinje for luftkvalitet. Maksimale konsentrasjoner i ferskvann fra utslippet er fra 0.6 % til 3.2 % av retningslinjen avhengig av hvilken absorbent som benyttes og hvilken avgass som renses. For likely case i forhold til worst case er luftkonsentrasjonene en faktor 3 til 4 lavere enn worst case. Ferskvannkonsentrasjonene blir en faktor fra 16 til 22 lavere enn worst case avhengig av hvilken absorbent som benyttes.
2011
2023
Unprecedented shifts in aerosol pollution sources in China under a decade of clean air actions
China is a major hotspot of black carbon (BC) emissions, contributing to climate warming and risk to public health. Here, our dual-isotope-constrained observations indicate stringent air pollution controls have drastically reduced coal-burning in North China over the past decade, marking a transition to a “post-coal” era compared to earlier 2012–2014. However, biomass-burning fraction (fbb) for north/central/east winter hazes has doubled from earlier (north/east) ~20%, with significantly higher fbb during polluted winters. Comparisons between observation and transport modelling show good alignment in BC concentrations but substantial discrepancies in source attribution (i.e., fbb). Leveraging radiocarbon measurements, advanced atmospheric modelling, and a Bayesian approach, our study identifies biases stemming from misallocated residential fuel types in emission inventories. These findings underscore the untapped potential to mitigate BC emissions by targeting rural biomass burning, while providing critical insights into BC source evolution to refine emission inventories and formulate effective air quality policies for China and other nations facing severe air pollution.
Springer Nature
2025
2017
Unleaded gasoline as a significant source of Pb emissions in the Subarctic
After the phasing out of leaded gasoline, Pb emissions to the atmosphere dramatically decreased, and other sources became more significant. The contribution of unleaded gasoline has not been sufficiently recognized; therefore, we evaluated the impact of Pb from unleaded gasoline in a relatively pristine area in Subarctic NE Norway. The influence of different endmembers (Ni slag and concentrate from the Nikel smelter in Russia, PM10 filters, and traffic) on the overall Pb emissions was determined using various environmental samples (snow, lichens, and topsoils) and Pb isotope tracing. We found a strong relationship between Pb in snow and the Ni smelter. However, lichen samples and most of the topsoils were contaminated by Pb originating from the current use of unleaded gasoline originating from Russia. Historical leaded and recent unleaded gasoline are fully distinguishable using Pb isotopes, as unleaded gasoline is characterized by a low radiogenic composition (206Pb/207Pb = 1.098 and 208Pb/206Pb = 2.060) and remains an unneglectable source of Pb in the region.
Elsevier
2018
Unexpected nascent atmospheric emissions of three ozone-depleting hydrochlorofluorocarbons
Global and regional atmospheric measurements and modeling can play key roles in discovering and quantifying unexpected nascent emissions of environmentally important substances. We focus here on three hydrochlorofluorocarbons (HCFCs) that are restricted by the Montreal Protocol because of their roles in stratospheric ozone depletion. Based on measurements of archived air samples and on in situ measurements at stations of the Advanced Global Atmospheric Gases Experiment (AGAGE) network, we report global abundances, trends, and regional enhancements for HCFC-132b (CH2ClCClF2), which is newly discovered in the atmosphere, and updated results for HCFC-133a (CH2ClCF3) and HCFC-31 (CH2ClF). No purposeful end-use is known for any of these compounds. We find that HCFC-132b appeared in the atmosphere 20 y ago and that its global emissions increased to 1.1 Gg⋅y−1 by 2019. Regional top-down emission estimates for East Asia, based on high-frequency measurements for 2016–2019, account for ∼95% of the global HCFC-132b emissions and for ∼80% of the global HCFC-133a emissions of 2.3 Gg⋅y−1 during this period. Global emissions of HCFC-31 for the same period are 0.71 Gg⋅y−1. Small European emissions of HCFC-132b and HCFC-133a, found in southeastern France, ceased in early 2017 when a fluorocarbon production facility in that area closed. Although unreported emissive end-uses cannot be ruled out, all three compounds are most likely emitted as intermediate by-products in chemical production pathways. Identification of harmful emissions to the atmosphere at an early stage can guide the effective development of global and regional environmental policy.
2021
2024
2018
Undersøkelse av svevestøv ved veier. Elevbasert forskningskampanje som del av Forskningsdagene 2004. NILU OR
2005
2003
2004