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Land cover and traffic data inclusion in PM mapping
Annual European-wide air quality maps have been produced using geostatistical techniques for many years and is based primarily on air quality measurements. The mapping method follows in principle the sequence of regression – interpolation – merging. It combines monitoring data, chemical transport model outputs and other supplementary data (such as altitude and meteorology) using a linear regression model followed by kriging of its residuals (‘residual kriging’), applied separately for rural and urban background areas. The rural and urban background map layers are
subsequently merged on basis of population densities into one final concentration map for Europe.
Inclusion of land cover and road type data among the set of the supplementary data demonstrated to improve the quality of urban and rural background layers in the NO2 map and is currently routinely applied in the NO2 mapping. In addition, an urban traffic map layer based on the measurement data from traffic stations is constructed and takes art in the merging process with the rural and urban background map layers to reach a final NO2 map.
This report examines now – due to its proved added value in the NO2 mapping – whether for PM10 and PM2.5 the similar method provides also sufficient added value to include it on a routinely basis in the production of the final concentration map and population exposure estimates.. It concerns the inclusion of land cover data and road type data in the background map layers, as well as the inclusion of the urban traffic layer based on traffic measurement stations. The analysis is done based on 2015 data, being the most recent year with all data needed available when this study started.
ETC/ACM
2019
2017
2008
2008
Land surface temperature determination from ATSR-family of instruments and the Sentinel-3 SLSTR. NILU PP
2010
Land surface temperature validation for WACMOS-ET. Reference input data set validation report. NILU report
The Land Surface Temperature (LST) products generated specifically for the WAter Cycle Observation Multi-mission Strategy - EvapoTranspiration (WACMOS-ET)project, funded by the European Space Agency (ESA), are evaluated with respect to their overall quality. LST products derived from observations acquired by the Advanced Along-Track Scanning Radiometer (AATSR), the Multi-Functional Transport Satellite (MTSAT), and the Geostationary Operational Environmental Satellite (GOES) were studied here. Following previously established best-practices on LST validation, the evaluation includes both a qualitative component addressing general issues with the data, as well as a quantitative component, which compares the LST products directly against a reference dataset. For the latter satellite LST is compared against both ground-based in situ datasets acting as a source of absolute reference data and against independent satellite-based LST products from other sensors to provide a spatially exhaustive relative comparison.
2017
2015
2014
2014
2016
1977
Langtransport av miljøgifter med avfall: En giftfri framtid på bekostning av fattige land? NILU F
Det er nå mindre forbudte industrielle miljøgifter i rike industriland som Norge, men nivåene er blitt helsefarlige i deler av Afrika og Asia. I dette foredraget vil du få høre om hvordan kontrolltiltak i rike land kan ha medført at fattige land har blitt en dumpingplass for giftig avfall.
2014
2016
2009
2025
Black Carbon (BC) aerosol is a major climate forcer in the Arctic. Here, we present 15 years (2001–2015) of surface observations of the aerosol absorption coefficient babs (corresponding to Equivalent BC), obtained at the Zeppelin Observatory, Ny Ålesund, Svalbard, coupled with backward transport modeling with Flexpart in order to calculate the Potential Source Contribution Function (PSCF) for BC. The observed long-term variability superimposed on a strong annual cycle is studied as a function of large-scale circulation patterns represented by monthly index values for the North Atlantic Oscillation (NAO) and the Scandinavian pattern (SCAN). We find a 35% increase of babs values at Zeppelin during the SCAN+ phase in the winter half-year compared to the SCAN+ phase but no significant difference in babs values between the NAO index phases. Both NAO and SCAN induce significant regional variability on the areas of origin of babs, mainly Siberia, Europe, and North America.
2021
Large eddy simulation of plume dispersion and concentration fluctuations in a neutral boundary layer
2018
2010
Large regional pollution episodes in Europe and status and perspectives of the EMEP Programme. NILU F
2014
Seasonal to interannual variations in the concentrations of sulfur aerosols (< 2.5 µm in diameter; non sea-salt sulfate: NSS-SO2−4; anthropogenic sulfate: Anth-SO2−4; biogenic sulfate: Bio-SO2−4; methanesulfonic acid: MSA) in the Arctic atmosphere were investigated using measurements of the chemical composition of aerosols collected at Ny-Ålesund, Svalbard (78.9∘ N, 11.9∘ E) from 2015 to 2019. In all measurement years the concentration of NSS-SO2−4 was highest during the pre-bloom period and rapidly decreased towards summer. During the pre-bloom period we found a strong correlation between NSS-SO2−4 (sum of Anth-SO2−4 and Bio-SO2−4) and Anth-SO2−4. This was because more than 50 % of the NSS-SO2−4 measured during this period was Anth-SO2−4, which originated in northern Europe and was subsequently transported to the Arctic in Arctic haze. Unexpected increases in the concentration of Bio-SO2−4 aerosols (an oxidation product of dimethylsulfide: DMS) were occasionally found during the pre-bloom period. These probably originated in regions to the south (the North Atlantic Ocean and the Norwegian Sea) rather than in ocean areas in the proximity of Ny-Ålesund. Another oxidation product of DMS is MSA, and the ratio of MSA to Bio-SO2−4 is extensively used to estimate the total amount of DMS-derived aerosol particles in remote marine environments. The concentration of MSA during the pre-bloom period remained low, primarily because of the greater loss of MSA relative to Bio-SO2−4 and the suppression of condensation of gaseous MSA onto particles already present in air masses being transported northwards from distant ocean source regions (existing particles). In addition, the low light intensity during the pre-bloom period resulted in a low concentration of photochemically activated oxidant species including OH radicals and BrO; these conditions favored the oxidation pathway of DMS to Bio-SO2−4 rather than to MSA, which acted to lower the MSA concentration at Ny-Ålesund. The concentration of MSA peaked in May or June and was positively correlated with phytoplankton biomass in the Greenland and Barents seas around Svalbard. As a result, the mean ratio of MSA to the DMS-derived aerosols was low (0.09 ± 0.07) in the pre-bloom period but high (0.32 ± 0.15) in the bloom and post-bloom periods. There was large interannual variability in the ratio of MSA to Bio-SO2−4 (i.e., 0.24 ± 0.11 in 2017, 0.40 ± 0.14 in 2018, and 0.36 ± 0.14 in 2019) during the bloom and post-bloom periods. This was probably associated with changes in the chemical properties of existing particles, biological activities surrounding the observation site, and air mass transport patterns. Our results indicate that MSA is not a conservative tracer for predicting DMS-derived particles, and the contribution of MSA to the growth of newly formed particles may be much larger during the bloom and post-bloom periods than during the pre-bloom period.
2021
2005