Publikasjoner

Atmospheric DMS in the Arctic Ocean and Its Relation to Phytoplankton Biomass

Plastic fantastic

Dynamical climate predictions at the Bjerknes Center

Inverse modelling of European CH4 emissions during 2006–2012 using different inverse models and reassessed atmospheric observations

We present inverse modelling (top down) estimates of European methane (CH4) emissions for 2006–2012 based on a new quality-controlled and harmonised in situ data set from 18 European atmospheric monitoring stations. We applied an ensemble of seven inverse models and performed four inversion experiments, investigating the impact of different sets of stations and the use of a priori information on emissions.

The inverse models infer total CH4 emissions of 26.8 (20.2–29.7) Tg CH4 yr−1 (mean, 10th and 90th percentiles from all inversions) for the EU-28 for 2006–2012 from the four inversion experiments. For comparison, total anthropogenic CH4 emissions reported to UNFCCC (bottom up, based on statistical data and emissions factors) amount to only 21.3 Tg CH4 yr−1 (2006) to 18.8 Tg CH4 yr−1 (2012). A potential explanation for the higher range of top-down estimates compared to bottom-up inventories could be the contribution from natural sources, such as peatlands, wetlands, and wet soils. Based on seven different wetland inventories from the Wetland and Wetland CH4 Inter-comparison of Models Project (WETCHIMP), total wetland emissions of 4.3 (2.3–8.2) Tg CH4 yr−1 from the EU-28 are estimated. The hypothesis of significant natural emissions is supported by the finding that several inverse models yield significant seasonal cycles of derived CH4 emissions with maxima in summer, while anthropogenic CH4 emissions are assumed to have much lower seasonal variability. Taking into account the wetland emissions from the WETCHIMP ensemble, the top-down estimates are broadly consistent with the sum of anthropogenic and natural bottom-up inventories. However, the contribution of natural sources and their regional distribution remain rather uncertain.

Furthermore, we investigate potential biases in the inverse models by comparison with regular aircraft profiles at four European sites and with vertical profiles obtained during the Infrastructure for Measurement of the European Carbon Cycle (IMECC) aircraft campaign. We present a novel approach to estimate the biases in the derived emissions, based on the comparison of simulated and measured enhancements of CH4 compared to the background, integrated over the entire boundary layer and over the lower troposphere. The estimated average regional biases range between −40 and 20 % at the aircraft profile sites in France, Hungary and Poland.

Maternal-Child Exposures to Persistent Organic Pollutants in Dhaka, Bangladesh

Information about the human burdens of persistent organic pollutants (POPs) in low- and middle-income countries is limited. In particular, studies often include only a small subset of POPs. To address this data gap, we aimed to assess maternal-child exposures to POPs in Dhaka, Bangladesh. We quantified 16 organochlorine pesticides, 12 polychlorinated biphenyls, 21 brominated flame retardants, 18 per- and polyfluorinated alkyl substances, 2 polycyclic aromatic hydrocarbons, and short-chain chlorinated paraffins in 18 pooled samples of human cord blood from 90 mother–infant pairs living in Dhaka, Bangladesh (2014–2015). In all pooled samples, we detected high levels of p,p′-DDT (median 81.6 ng/g lipid) and its metabolites p,p′-DDE and p,p′-DDD (median 551 and 10.7 ng/g lipid, respectively), where the p,p′-DDE/p,p′-DDT ratio ranged from 2.9 to 9.8 indicating recent dichlorodiphenyltrichloroethane (DDT) exposure. We also detected acenaphthene, decabromodiphenyl ethane, o,p′-DDT, o,p′-DDE, hexachlorobenzene, β-hexachlorocyclohexane, hexabromobenzene, and perfluorooctanoic acid in a subset of samples. For the other 59 target compounds, concentrations were below the limits of detection, despite using ultra-trace analytical methodology. No trends were observed when stratifying the analyses of detected POP concentrations by maternal age, maternal body mass index, or large fish consumption. These findings highlight recent DDT exposure in Dhaka, but the overall POP burden was otherwise low in this sample of pregnant women/newborns. Future monitoring efforts should focus on newly detected POPs for which burdens may be increasing due to ongoing industrialization in Bangladesh.

Flukskart av CH4 og CO2

ACTRIS Data Centre Concept and requirements

A Portable Tool for the Evaluation of Microclimate Conditions within Museum Enclosures, Transit Frames, and Transport Cases

Assessment of heavy metal transboundary pollution on global, regional and national scales

Meteorological Synthesizing Centre - East (MSC-E)

Luftkvalitetsmålingene i Tromsø holder mål

Du kan stole på målingene i Bergen

Validation of nitrogen dioxide and Arctic methane from S5P (VANDAM)

Kinetics of POP sorption and plastic additive release to a variety of polymers under Arctic conditions

The PLASTOX project investigates the ingestion, food-web transfer, and ecotoxicological impact of microplastics (MPs), together with the persistent organic pollutants (POPs), metals and plastic additive chemicals associated with them, on key European marine species and ecosystems. PLASTOX combines field-based observations, laboratory tests and manipulative field experiments to study the ecological effects of MPs.

As part of a long-term field experiment conducted at marine locations across Europe (Mediterranean to Arctic), a range of different virgin polymer pellets, post-use polymers (LDPE, PP, PS and PET), as well as marine litter-derived microplastic particles, were deployed underwater for up to 12 months in the small boat harbour of Tromsø, Northern Norway. The deployment device consisted of an empty stainless steel SPMD canister, with the various plastic types placed in reusable, empty 'teabags' made of PP, placed separately in nylon netting. Sampling was conducted 1 week, 1 month, 3 months, 6 months and 12 months after deployment. Hydrophobic persistent organic pollutants such as PAHs, PCBs, DDTs, PBDEs and pesticides that had become associated with the plastic were measured and their adsorption kinetics in seawater under Arctic conditions established. Samples were extracted using ultrasound and non-polar solvents, followed by GPC and SPE clean up prior to chemical analysis and quantification by GC/MS/MS and GC/qMS. The release kinetics of common plastic additives, including phthalates, organophosphate esters, bisphenols and perfluorinated chemicals, were estimated from four types of post-industrial virgin pellets (LDPE, PS, PVC, PET) according to the same sampling protocol. Chemical analysis was performed using either GC/MS or LC-QTOF.

Results show that HCB and PCBs represented the dominant pollutant classes adsorbing to all of the different polymer types, but at concentrations that are more than 10-times lower than those previously reported. However, equilibrium between pollutants and the polymers was not reached during the deployment period, indicating that Arctic conditions may result in different sorption kinetics than observed in temperate regions.