Publications

Estimating volcanic ash emissions using retrieved satellite ash columns and inverse ash transport modelling using VolcanicAshInversion v1.2.1, within the operational eEMEP volcanic plume forecasting system (version rv4_17)

Brodtkorb, André R.; Benedictow, Anna Maria Katarina; Klein, Heiko; Kylling, Arve; Nyiri, Agnes; Valdebenito Bustamante, Alvaro Moises; Sollum, Espen; Kristiansen, Nina Iren

Accurate modeling of ash clouds from volcanic eruptions requires knowledge about the eruption source parameters including eruption onset, duration, mass eruption rates, particle size distribution, and vertical-emission profiles. However, most of these parameters are unknown and must be estimated somehow. Some are estimated based on observed correlations and known volcano parameters. However, a more accurate estimate is often needed to bring the model into closer agreement with observations.

This paper describes the inversion procedure implemented at the Norwegian Meteorological Institute for estimating ash emission rates from retrieved satellite ash column amounts and a priori knowledge. The overall procedure consists of five stages: (1) generate a priori emission estimates, (2) run forward simulations with a set of unit emission profiles, (3) collocate/match observations with emission simulations, (4) build system of linear equations, and (5) solve overdetermined systems. We go through the mathematical foundations for the inversion procedure, performance for synthetic cases, and performance for real-world cases. The novelties of this paper include a memory efficient formulation of the inversion problem, a detailed description and illustrations of the mathematical formulations, evaluation of the inversion method using synthetic known-truth data as well as real data, and inclusion of observations of ash cloud-top height. The source code used in this work is freely available under an open-source license and is able to be used for other similar applications.

Estimation of Arctic ozone loss in winter 2004/05 based on assimilation of EOS MLS and SBUV/2 observations.

Jackson, D.R.; Orsolini, Y.J.

Estimation of daytime NO3 radical levels in the UK urban atmosphere using the steady state approximation method.

Khan, M.A.H.; Morris, W.C.; Watson, L.A.; Galloway, M.; Hamer, P.D.; Shallcross, B.M.A.; Percival, C.J.; Shallcross, D.E.

Estimation of eddies and flows around buildings. Powerpoint presentation. NILU F

Svenningsen, G.

Estimation of methane fluxes in the high northern latitudes from a Bayesian atmospheric inversion.

Thompson, R. L.; Stohl, A.; Myhre, C. L.; Sasakawa, M.; Machida, T. Aalto, T.; Dlugokencky, E.; Worthy, D.

Estimation of spatio-temporal source of microplastics using Bayesian Neural networks

Brožová, Antonie; Šmídl, Václav; Tichý, Ondřej; Evangeliou, Nikolaos

Estimation Of Surface NO2 Concentration Over Europe Using Sentinel-5P Observations And Machine Learning Models

Shetty, Shobitha; Schneider, Philipp; Stebel, Kerstin; Hamer, Paul David; Kylling, Arve

Estimation of the historical dry deposition of air pollution indoors to the monumental paintings by Edvard Munch in the University Aula, in Oslo, Norway

Grøntoft, Terje; Frøysaker, Tine

The historical (1835–2020) deposition of major air pollutants (SO2, NOx, O3 and PM2.5) indoors, as represented by the monumental Edvard Munch paintings (c. 220 m2) installed in 1916 in the Oslo University Aula in Norway, were approximated from the outdoor air concentrations, indoor to outdoor concentration ratios and dry deposition velocities. The annual deposition of the pollutants to the paintings was found to have been 4–25 times lower than has been reported to buildings outdoors in the urban background in the centre of Oslo. It reflected the outdoor deposition but varied less, from 0.3 to 1.2 g m−2 a−1. The accumulated deposition since 1916, and then not considering the regularly performed cleaning of the paintings, was found to have been 43 ± 13 g m−2, and 110 ± 40 g m−2 in a similar situation since 1835. The ozone deposition, and the PM2.5 deposition before the 1960s, were a relatively larger part of the accumulated total indoor (to the paintings) than reported outdoor deposition. About 18 and 33 times more O3 than NOx and PM2.5 deposition was estimated to the paintings in 2020, as compared to the about similar reported outdoor dry deposition of O3 and NOx. The deposition of PM2.5 to the paintings was probably reduced with about 62% (50–80%) after installation of mechanical filtration in 1975 and was estimated to be 0.011 (± 0.006) g m−2 in 2020.

BioMed Central (BMC)

Estimation of the vertical profile of SO2 injection by a volcanic eruption. NILU PP

Eckhardt, S.; Prata, A.J.; Seibert, P.; Stebel, K.; Stohl, A.

Estimation of the vertical profile of sulfur dioxide injection into the atmosphere by a volcanic eruption using satellite column measurements and inverse transport modeling.

Eckhardt, S.; Prata, A.J.; Seibert, P.; Stebel, K.; Stohl, A.

Estimation on air pollution from alternative roads Ringveg Vest, Bergen. NILU OR

Haugsbakk, I.

Estrogen-like properties of fluorotelomer alcohols as revealed by MCF-7 breast cancer cell proliferation. NILU PP

Maras, M.; Vanparys, C.; Berger, U.; Barber, J.L.; Blust, R.; De Coen, W.