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2018
2018
Meteorological Synthesizing Centre - East (MSC-E)
2018
2018
The aim of the present study was to investigate the presence and bioaccumulation of new flame retardants (nBFRs), polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DDC-CO) in the marine environment close to an Arctic community. Passive sampling of air and water and grab sampling of sediment and amphipods was used to obtain samples to study long-range transport versus local contributions for regulated and emerging flame retardants in Longyearbyen, Svalbard. BDE-47 and -99, α- and β-tetrabromoethylcyclohexane (DBE-DBCH), syn- and anti-dechlorane plus (DDC-CO) were detected in all investigated matrices and the DDC-COss at higher concentrations in the air than reported from other remote Arctic areas. Water concentrations of ΣDDC-COSs were low (3 pg/L) and comparable to recent Arctic studies. ΣnBFR was 37 pg/L in the water samples while ΣPBDE was 3 pg/L. In biota, ΣDDC-COSs dominated (218 pg/g ww) followed by ΣnBFR (95 pg/g ww) and ΣPBDEs (45 pg/g ww). When compared with other areas and their relative distribution patterns, contributions from local sources of the analysed compounds cannot be ruled out. This should be taken into account when assessing long-range transport of nBFRs and DDC-COs to the Arctic. High concentrations of PBDEs in the sediment indicate that they might originate from a small, local source, while the results for some of the more volatile compounds such as hexabromobenzene (HBBz) suggest long-range transport to be more important than local sources. We recommend that local sources of flame retardants in remote areas receive more attention in the future.
2018
Warm Arctic–cold Siberia: comparing the recent and the early 20th century Arctic warmings
The Warm Arctic–cold Siberia surface temperature pattern during recent boreal winter is suggested to be triggered by the ongoing decrease of Arctic autumn sea ice concentration and has been observed together with an increase in mid-latitude extreme events and a meridionalization of tropospheric circulation. However, the exact mechanism behind this dipole temperature pattern is still under debate, since model experiments with reduced sea ice show conflicting results. We use the early twentieth-century Arctic warming (ETCAW) as a case study to investigate the link between September sea ice in the Barents–Kara Sea (BKS) and the Siberian temperature evolution. Analyzing a variety of long-term climate reanalyses, we find that the overall winter temperature and heat flux trend occurs with the reduction of September BKS sea ice. Tropospheric conditions show a strengthened atmospheric blocking over the BKS, strengthening the advection of cold air from the Arctic to central Siberia on its eastern flank, together with a reduction of warm air advection by the westerlies. This setup is valid for both the ETCAW and the current Arctic warming period.
2018
2018
2018
Air quality in Norwegian cities in 2015. Evaluation Report for NBV Main Results.
This report documents the final deliveries of the first phase of development of the Norwegian Air Quality Planning Tool,
also called “Nasjonalt Beregningsverktøy” or NBV. The main purpose of NBV is to provide a common methodological and
information platform for local air quality modelling applications. The system is addressed to local and regional
environmental authorities, air quality experts and consulting companies. It is intended to help them meet the requirements
of current air quality legislation, to support local air quality planning and facilitate air quality good practices where people live.
The report constitutes a comprehensive user guide for the NBV services available at http://www.luftkvalitet-nbv.no. It
presents each of the different products developed at NBV, documents how the product has been calculated, provides
recommendations on how best to use it for planning purposes and explains the main strengths and limitations of each
product. The report also includes an extensive validation of the air quality information currently available at NBV.
NILU
2018
Equinors miljøovervåkingsprogram for Snøhvit. Overvåking av vegetasjon og jord – reanalyser i 2018
Petroleumsanlegget på Melkøya utenfor Hammerfest ble startet opp i 2007 og slipper ut karbon-dioksid (CO2), nitrogenoksider (NOx), metan (CH4), flyktige organiske forbindelser utenom metan (nmVOC), svoveldioksid (SO2) og hydrogensulfid (H2S) fra energiproduksjon og prosessanlegg. Utslipp av nitrogen og svovelholdige gasser kan generelt påvirke terrestriske økosystemer ved forsuring og gjødsling av jordsmonn og vegetasjon. Petroleumsanlegget på Melkøya tar imot naturgass fra feltene Snøhvit og Albatross i Barentshavet. Her prosesseres og nedkjøles natur-gassen til flytende gass (LNG) for videre distribuering. Utslippene fra LNG-anlegget er beregnet til å ligge under gjeldene kritiske tålegrenseverdier for terrestriske naturtyper, men tålegrense-verdiene i arktisk/alpine naturtyper er imidlertid usikre. For å kunne dokumentere eventuelle ef-fekter av utslipp til luft, ble det i 2006 (før utslipp) etablert et overvåkingsprogram for vegetasjon og jord i influensområdet fra LNG-anlegget på Melkøya. Grunnlagsundersøkelsen ble utført samme år, og det ble utført analyser i 2008, 2013 og 2018 etter samme metodikk som i 2006.
To overvåkingsområder ble opprettet i 2006, ett med estimert relativt høy avsetning av nitrogen, nordøst på Kvaløya ved Forsøl og ett område med relativt lav avsetning sør på Kvaløya ved Stangnes. Områdene er samkjørt med Norsk institutt for luftforskning (NILU) sine overvåkings-stasjoner for luft- og nedbørskvalitet. Innen hvert område utføres det en integrert overvåking av vegetasjonens artssammensetning og kjemisk innhold av planter og jord i to atskilte naturtyper (næringsfattig kreklinghei og litt kalkfattig og svakt intermediær jordvannsmyr).
Vegetasjonen overvåkes i permanent oppmerkede ruter (1m × 1m i arktisk hei og 0,5m × 0,5m på myr). I hver rute registreres mengde av karplanter, moser og lav, samt vegetasjonssjiktenes høyde og dekning. Lys reinlav/fjellreinlav (reinlav) og rusttorvmose analyseres for kjemisk inn-hold, Kjeldahl-nitrogen, tungmetallene bly (Pb), nikkel (Ni) og sink (Zn) og polyaromatiske hydro-karboner (PAH). Jordprøver fra hver av naturtypene analyseres for pH, Kjeldahl-nitrogen, ekstraherbare kationer, utbyttingskapasitet, basemetning, Pb, Ni, Zn og PAH. De kjemiske analysene av planter og jord utføres av Norsk institutt for bioøkonomi og NILU.
Analysene av vegetasjonens artssammensetning viste få endringer i mengdeforhold mellom artene fra 2006 til 2018. De små endringene vi fant skyldes trolig årlige variasjoner. Det ble funnet noen få endringer av arter som normalt responderer positivt på nitrogengjødsling, slik som gress. Lav har gått noe tilbake mest sannsynlig pga. økt beitepress fra rein. Det er således ingen indikasjon på at en eventuell forurensing fra LNG-anlegget på Melkøya har påvirket vegetasjonens artssammensetning og mengdeforholdet mellom arter.
NØKKELORD : Hammerfest, Melkøya, Kvaløya, LNG-anlegg, forurensing, forsuring, gjødsling, nitrogen, arktisk/ alpin vegetasjon, kreklinghei, myr, plantekjemi, jordkjemi, polyaromatiske hydrokarboner,
KEY WORDS : Hammerfest, Melkøya, Kvaløya, LNG plant, pollution, acidification, fertilization, nitrogen, arctic/ alpine vegetation, mire, plant chemistry, soil chemistry, polynuclear aromatic hydrocarbons
Norsk institutt for naturforskning
2018
2018
Based on observations of the chlorofluorocarbons CFC-13 (chlorotrifluoromethane), ΣCFC-114 (combined measurement of both isomers of dichlorotetrafluoroethane), and CFC-115 (chloropentafluoroethane) in atmospheric and firn samples, we reconstruct records of their tropospheric histories spanning nearly 8 decades. These compounds were measured in polar firn air samples, in ambient air archived in canisters, and in situ at the AGAGE (Advanced Global Atmospheric Gases Experiment) network and affiliated sites. Global emissions to the atmosphere are derived from these observations using an inversion based on a 12-box atmospheric transport model. For CFC-13, we provide the first comprehensive global analysis. This compound increased monotonically from its first appearance in the atmosphere in the late 1950s to a mean global abundance of 3.18 ppt (dry-air mole fraction in parts per trillion, pmol mol−1) in 2016. Its growth rate has decreased since the mid-1980s but has remained at a surprisingly high mean level of 0.02 ppt yr−1 since 2000, resulting in a continuing growth of CFC-13 in the atmosphere. ΣCFC-114 increased from its appearance in the 1950s to a maximum of 16.6 ppt in the early 2000s and has since slightly declined to 16.3 ppt in 2016. CFC-115 increased monotonically from its first appearance in the 1960s and reached a global mean mole fraction of 8.49 ppt in 2016. Growth rates of all three compounds over the past years are significantly larger than would be expected from zero emissions. Under the assumption of unchanging lifetimes and atmospheric transport patterns, we derive global emissions from our measurements, which have remained unexpectedly high in recent years: mean yearly emissions for the last decade (2007–2016) of CFC-13 are at 0.48 ± 0.15 kt yr−1 (> 15 % of past peak emissions), of ΣCFC-114 at 1.90 ± 0.84 kt yr−1 (∼ 10 % of peak emissions), and of CFC-115 at 0.80 ± 0.50 kt yr−1 (> 5 % of peak emissions). Mean yearly emissions of CFC-115 for 2015–2016 are 1.14 ± 0.50 kt yr−1 and have doubled compared to the 2007–2010 minimum. We find CFC-13 emissions from aluminum smelters but if extrapolated to global emissions, they cannot account for the lingering global emissions determined from the atmospheric observations. We find impurities of CFC-115 in the refrigerant HFC-125 (CHF2CF3) but if extrapolated to global emissions, they can neither account for the lingering global CFC-115 emissions determined from the atmospheric observations nor for their recent increases. We also conduct regional inversions for the years 2012–2016 for the northeastern Asian area using observations from the Korean AGAGE site at Gosan and find significant emissions for ΣCFC-114 and CFC-115, suggesting that a large fraction of their global emissions currently occur in northeastern Asia and more specifically on the Chinese mainland.
2018
2018
Methane at Svalbard and over the European Arctic Ocean
Methane (CH<sub>4</sub>) is a powerful greenhouse gas. Its atmospheric mixing ratios have been increasing since 2005. Therefore, quantification of CH<sub>4</sub> sources is essential for effective climate change mitigation. Here we report observations of the CH<sub>4</sub> mixing ratios measured at the Zeppelin Observatory (Svalbard) in the Arctic and aboard the research vessel (RV) Helmer Hanssen over the Arctic Ocean from June 2014 to December 2016, as well as the long-term CH<sub>4</sub> trend measured at the Zeppelin Observatory from 2001 to 2017. We investigated areas over the European Arctic Ocean to identify possible hotspot regions emitting CH<sub>4</sub> from the ocean to the atmosphere, and used state-of-the-art modelling (FLEXPART) combined with updated emission inventories to identify CH<sub>4</sub> sources. Furthermore, we collected air samples in the region as well as samples of gas hydrates, obtained from the sea floor, which we analysed using a new technique whereby hydrate gases are sampled directly into evacuated canisters. Using this new methodology, we evaluated the suitability of ethane and isotopic signatures (δ<sup>13</sup>C in CH<sub>4</sub>) as tracers for ocean-to-atmosphere CH<sub>4</sub> emission. We found that the average methane / light hydrocarbon (ethane and propane) ratio is an order of magnitude higher for the same sediment samples using our new methodology compared to previously reported values, 2379.95 vs. 460.06, respectively. Meanwhile, we show that the mean atmospheric CH<sub>4</sub> mixing ratio in the Arctic increased by 5.9±0.38 parts per billion by volume (ppb) per year (yr<sup>−1</sup>) from 2001 to 2017 and ∼8 pbb yr<sup>−1</sup> since 2008, similar to the global trend of ∼ 7–8 ppb yr<sup>−1</sup>. Most large excursions from the baseline CH<sub>4</sub> mixing ratio over the European Arctic Ocean are due to long-range transport from land-based sources, lending confidence to the present inventories for high-latitude CH<sub>4</sub> emissions. However, we also identify a potential hotspot region with ocean–atmosphere CH<sub>4</sub> flux north of Svalbard (80.4∘ N, 12.8∘ E) of up to 26 nmol m<sup>−2</sup>s<sup>−1</sup> from a large mixing ratio increase at the location of 30 ppb. Since this flux is consistent with previous constraints (both spatially and temporally), there is no evidence that the area of interest north of Svalbard is unique in the context of the wider Arctic. Rather, because the meteorology at the time of the observation was unique in the context of the measurement time series, we obtained over the short course of the episode measurements highly sensitive to emissions over an active seep site, without sensitivity to land-based emissions.
2018