Publications

Improved protection of paintings during exhibition, storage and transit - PROPAINT (EU project FP6, 044254).

Grøntoft, T.; Dahlin, E.; Odlyha, M.; Scharff, M.; Andrade, G.; Mottner, P.; Czop, J.; Colombini, P.; Hackney, S.; Wadum, J.

Improved optical flow velocity analysis in SO2 camera images of volcanic plumes – implications for emission-rate retrievals investigated at Mt Etna, Italy and Guallatiri, Chile

Gliss, Jonas; Stebel, Kerstin; Kylling, Arve; Sudbø, Aasmund

Accurate gas velocity measurements in emission plumes are highly desirable for various atmospheric remote sensing applications. The imaging technique of UV SO2 cameras is commonly used to monitor SO2 emissions from volcanoes and anthropogenic sources (e.g. power plants, ships). The camera systems capture the emission plumes at high spatial and temporal resolution. This allows the gas velocities in the plume to be retrieved directly from the images. The latter can be measured at a pixel level using optical flow (OF) algorithms. This is particularly advantageous under turbulent plume conditions. However, OF algorithms intrinsically rely on contrast in the images and often fail to detect motion in low-contrast image areas. We present a new method to identify ill-constrained OF motion vectors and replace them using the local average velocity vector. The latter is derived based on histograms of the retrieved OF motion fields. The new method is applied to two example data sets recorded at Mt Etna (Italy) and Guallatiri (Chile). We show that in many cases, the uncorrected OF yields significantly underestimated SO2 emission rates. We further show that our proposed correction can account for this and that it significantly improves the reliability of optical-flow-based gas velocity retrievals.

In the case of Mt Etna, the SO2 emissions of the north-eastern crater are investigated. The corrected SO2 emission rates range between 4.8 and 10.7 kg s−1 (average of 7.1  ±  1.3 kg s−1) and are in good agreement with previously reported values. For the Guallatiri data, the emissions of the central crater and a fumarolic field are investigated. The retrieved SO2 emission rates are between 0.5 and 2.9 kg s−1 (average of 1.3  ±  0.5 kg s−1) and provide the first report of SO2 emissions from this remotely located and inaccessible volcano.

Importance of integration and implementation of emerging and future mercury research into the Minamata convention.

Gustin, M.S.; Evers, D.C.; Bank, M.S.; Hammerschmidt, C.R.; Pierce, A.; Basu, N.; Blum, J.; Bustamante, P.; Chen, C.; Driscoll, C.T.; Horvat, M.; Jaffe, D.; Pacyna, J.; Pirrone, N.; Selin, N.

Import, use, and emissions of PCBs in Switzerland from 1930 to 2100.

Glüge, J.; Steinlin, C.; Schalles, S.; Wegmann, L.; Tremp, J.; Breivik, K.; Hungerbühler, K.; Bogdal, C.

Implications of Regurgitative Feeding on Plastic Loads in Northern Fulmars (Fulmarus glacialis): A Study from Svalbard

Tulatz, Felix; Gabrielsen, Geir Wing; Bourgeon, Sophie; Herzke, Dorte; Krapp, Rupert; Langset, Magdalene; Neumann, Svenja; Lippold, Anna; Collard, France

Procellariiform seabirds like northern fulmars (Fulmarus glacialis) are prone to ingest and accumulate floating plastic pieces. In the North Sea region, there is a long tradition to use beached fulmars as biomonitors for marine plastic pollution. Monitoring data revealed consistently lower plastic burdens in adult fulmars compared to younger age classes. Those findings were hypothesized to partly result from parental transfer of plastic to chicks. However, no prior study has examined this mechanism in fulmars by comparing plastic burdens in fledglings and older fulmars shortly after the chick-rearing period. Therefore, we investigated plastic ingestion in 39 fulmars from Kongsfjorden (Svalbard), including 21 fledglings and 18 older fulmars (adults/older immatures). We found that fledglings (50−60 days old) had significantly more plastic than older fulmars. While plastic was found in all fledglings, two older fulmars contained no and several older individuals barely any plastic. These findings supported that fulmar chicks from Svalbard get fed high quantities of plastic by their parents. Adverse effects of plastic on fulmars were indicated by one fragment that perforated the stomach and possibly one thread perforating the intestine. Negative correlations between plastic mass and body fat in fledglings and older fulmars were not significant.

Implementing the EMEP monitoring strategy and relation to the AQD-revision process. NILU F

Tørseth, K.

Implementering av de nye nasjonale forskrifter for lokal luftkvalitet. NILU F

Tørnkvist, K.

Implementation of state-of-the-art ternary new-particle formation scheme to the regional chemical transport model PMCAMx-UF in Europe.

Baranizadeh, E.; Murphy, B. N.; Julin, J.; Falahat, S.; Reddington, C. L.; Arola, A.; Ahlm, L.; Mikkonen, S.; Fountoukis, C.; Patoulias, D.; Minikin, A.; Hamburger, T.; Laaksonen, A.; Pandis, S. N.; Vehkamäki, H.; Lehtinen, K. E. J.; Riipinen, I.

Implementation of extraction routine for ECMWF data through the Calval web-pages. Final development report. NILU OR

Vik, A.F.; Krognes, T.; Walker, S.E.; Bårde, T.; Paltiel, R.; Tørnkvist, K.K.; Gloslie, B.; Larsen, R.; Thanh, T.N.

Impacts, outputs and effects from Sida-funded air quality management projects in Thailand and the Philippines. Sida Evaluation 06/14

Bower, J.; Sivertsen, B.; Larssen, S.

Impacts of UV Irradiance and Particle Precipitation on the North Atlantic Oscillation During the 11-year Solar Cycle

Orsolini, Yvan J.; Guttu, Sigmund; Stordal, Frode; Otterå, Odd Helge; Omrani, Nour-Eddine; Tartaglione, Nazario; Verronen, Pekka T.; Rodger, Craig J.; Clilverd, Mark A.

Impacts of the autumn Arctic sea ice on the intraseasonal reversal of the winter Siberian high

Lü, Zhuozhuo; He, Shengping; Li, Fei; Wang, Huijun

Science Press