John Faulkner Burkhart

• Filhol, Simon; Lefeuvre, Pierre-Marie; Ibañez, Juan David; Hulth, John; Hudson, Stephen & Gallet, Jean-Charles [Vis alle 8 forfattere av denne artikkelen] (2023). A new approach to meteorological observations on remote polar glaciers using open-source internet of things technologies. Frontiers in Environmental Science. ISSN 2296-665X. 11. doi: 10.3389/fenvs.2023.1085708. Fulltekst i vitenarkiv
• Burkhart, John; Matt, Felix Nikolaus; Helset, Sigbjørn; Abdella, Yisak Sultan; Skavhaug, Ola & Silantyeva, Olga (2021). Shyft v4.8: A Framework for Uncertainty Assessment and Distributed Hydrologic Modelling for Operational Hydrology . Geoscientific Model Development. ISSN 1991-959X. 14(2), s. 821–842. doi: 10.5194/gmd-14-821-2021. Fulltekst i vitenarkiv
• Teweldebrhan, Aynom Tesfay; Schuler, Thomas; Burkhart, John & Hjorth-Jensen, Morten (2020). Coupled machine learning and the limits of acceptability approach applied in parameter identification for a distributed hydrological model. Hydrology and Earth System Sciences (HESS). ISSN 1027-5606. 24, s. 4641–4658. doi: 10.5194/hess-24-4641-2020. Fulltekst i vitenarkiv
• Bhattarai, Bikas Chandra; Burkhart, John; Tallaksen, Lena M.; Xu, Chong-Yu & Matt, Felix Nikolaus (2020). Evaluation of global forcing datasets for hydropower inflow simulation in Nepal. Hydrology Research. ISSN 1998-9563. 51(2), s. 202–225. doi: 10.2166/nh.2020.079. Fulltekst i vitenarkiv
• Bhattarai, Bikas Chandra; Silantyeva, Olga; Teweldebrhan, Aynom Tesfay; Helset, Sigbjørn; Skavhaug, Ola & Burkhart, John (2020). Impact of Catchment Discretization and Imputed Radiation on Model Response: A Case Study from Central Himalayan Catchment. Water. ISSN 2073-4441. 12( 9). doi: 10.3390/w12092339. Fulltekst i vitenarkiv
• Eriksrød, Jon Håvard; Burkhart, John; Lande, Tor Sverre & Hamran, Svein-Erik (2020). Bistatic SAR Radar for Long-Term Snow Pack Monitoring. IEEE Transactions on Geoscience and Remote Sensing. ISSN 0196-2892. 58(1), s. 218–226. doi: 10.1109/TGRS.2019.2935781.
• Magnusson, Jan; Nævdal, Geir; Matt, Felix; Burkhart, John F & Winstral, Adam (2020). Improving hydropower inflow forecasts by assimilating snow data . Hydrology Research. ISSN 1998-9563. 51(2), s. 226–237. doi: 10.2166/nh.2020.025. Fulltekst i vitenarkiv Vis sammendrag

  Accurate long-term inflow forecasts are essential for optimal planning of hydropower production. In snow-rich regions, where spring snowmelt is often the largest reservoir of water, inflow forecasts may be improved by assimilating snow observations to achieve more accurate initial states for the hydrological models prior to the prognosis. In this study, we test whether an ensemble Kalman based approach is useful for this purpose for a mountainous catchment in Norway. For 15 years, annual snow observations near peak accumulation at three locations were assimilated into a distributed hydrological model. After the update, the model was run for a 4-month forecasting period with inflows compared to a base case scenario that omitted the snow observations. The assimilation framework improved the forecasts in several years, and in two of the years, the improvement was very large compared to the base case simulation. At the same time, the filter did not degrade the forecasts largely, indicating that though the updating might slightly degrade performance in some years, it maintains the potential for large improvements in others. Thus, the framework proposed here is a viable method for improving snow-related deficiencies in the initial states, which translates to better forecasts.

• Pisso, Ignacio; Sollum, Espen; Grythe, Henrik; Kristiansen, Nina Iren; Cassiani, Massimo & Eckhardt, Sabine [Vis alle 21 forfattere av denne artikkelen] (2019). The Lagrangian particle dispersion model FLEXPART version 10.4. Geoscientific Model Development. ISSN 1991-959X. 12(12), s. 4955–4997. doi: 10.5194/gmd-12-4955-2019. Fulltekst i vitenarkiv Vis sammendrag

  The Lagrangian particle dispersion model FLEXPART in its original version in the mid-1990s was designed for calculating the long-range and mesoscale dispersion of hazardous substances from point sources, such as those released after an accident in a nuclear power plant. Over the past decades, the model has evolved into a comprehensive tool for multi-scale atmospheric transport modeling and analysis and has attracted a global user community. Its application fields have been extended to a large range of atmospheric gases and aerosols, e.g., greenhouse gases, short-lived climate forcers like black carbon and volcanic ash, and it has also been used to study the atmospheric branch of the water cycle. Given suitable meteorological input data, it can be used for scales from dozens of meters to global. In particular, inverse modeling based on source–receptor relationships from FLEXPART has become widely used. In this paper, we present FLEXPART version 10.4, which works with meteorological input data from the European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecast System (IFS) and data from the United States National Centers of Environmental Prediction (NCEP) Global Forecast System (GFS). Since the last publication of a detailed FLEXPART description (version 6.2), the model has been improved in different aspects such as performance, physicochemical parameterizations, input/output formats, and available preprocessing and post-processing software. The model code has also been parallelized using the Message Passing Interface (MPI). We demonstrate that the model scales well up to using 256 processors, with a parallel efficiency greater than 75 % for up to 64 processes on multiple nodes in runs with very large numbers of particles. The deviation from 100 % efficiency is almost entirely due to the remaining nonparallelized parts of the code, suggesting large potential for further speedup. A new turbulence scheme for the convective boundary layer has been developed that considers the skewness in the vertical velocity distribution (updrafts and downdrafts) and vertical gradients in air density. FLEXPART is the only model available considering both effects, making it highly accurate for small-scale applications, e.g., to quantify dispersion in the vicinity of a point source. The wet deposition scheme for aerosols has been completely rewritten and a new, more detailed gravitational settling parameterization for aerosols has also been implemented. FLEXPART has had the option of running backward in time from atmospheric concentrations at receptor locations for many years, but this has now been extended to also work for deposition values and may become useful, for instance, for the interpretation of ice core measurements. To our knowledge, to date FLEXPART is the only model with that capability. Furthermore, the temporal variation and temperature dependence of chemical reactions with the OH radical have been included, allowing for more accurate simulations for species with intermediate lifetimes against the reaction with OH, such as ethane. Finally, user settings can now be specified in a more flexible namelist format, and output files can be produced in NetCDF format instead of FLEXPART's customary binary format. In this paper, we describe these new developments. Moreover, we present some tools for the preparation of the meteorological input data and for processing FLEXPART output data, and we briefly report on alternative FLEXPART versions.

• Filhol, Simon; Perret, Alexis; Girod, Luc Maurice Ramuntcho; Sutter, Guillaume; Schuler, Thomas & Burkhart, John (2019). Time-lapse photogrammetry of distributed snow depth during snowmelt. Water Resources Research. ISSN 0043-1397. 55(9), s. 7916–7926. doi: 10.1029/2018WR024530. Fulltekst i vitenarkiv Vis sammendrag

  Characterizing snowmelt both spatially and temporally from in situ observation remains a challenge. Available sensors (i.e., sonic ranger, lidar, airborne photogrammetry) provide either time series of local point measurements or sporadic surveys covering larger areas. We propose a methodology to recover from a minimum of three synchronized time-lapse cameras changes in snow depth and snow cover extent over area smaller or equivalent to 0.12 km2 . Our method uses photogrammetry to compute point clouds from a set of three or more images and automatically repeat this task for the entire time series. The challenges were (1) finding an optimal experimental setup deployable in the field, (2) estimating the error associated with this technique, and (3) being able to minimize the input of manual work in the data processing pipeline. Developed and tested in the field in Finse, Norway, over 1 month during the 2018 melt season, we estimated a median melt of 2.12 ± 0.48 m derived from three cameras 1.2 km away from the region of interest. The closest weather station recorded 1.94 m of melt. Other parameters like snow cover extent and duration could be estimated over a 300 × 400m region. The software is open source and applicable to a broader range of geomorphologic processes like glacier dynamic, snow accumulation, or any other processes of surface deformation, with the conditions of (1) having fixed visible points within the area of interest and (2) resolving sufficient surface textures in the photographs.

• Bhattarai, Bikas Chandra; Burkhart, John; Stordal, Frode & Xu, Chong-Yu (2019). Aerosol Optical Depth Over the Nepalese Cryosphere Derived From an Empirical Model . Frontiers in Earth Science. ISSN 2296-6463. 7. doi: 10.3389/feart.2019.00178. Fulltekst i vitenarkiv
• Santra, Sauvik; Verma, Shubha; Fujita, Koji; Chakraborty, Indrajit; Boucher, Olivier & Takemura, Toshihiko [Vis alle 9 forfattere av denne artikkelen] (2019). Simulations of black carbon (BC) aerosol impact over Hindu Kush Himalayan sites: Validation, sources, and implications on glacier runoff. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 19(4), s. 2441–2460. doi: 10.5194/acp-19-2441-2019. Fulltekst i vitenarkiv
• Parajka, Juraj; Bezak, Nejc; Burkhart, John; Hauksson, Bjarki; Holko, Ladislav & Hundecha, Yeshewa [Vis alle 15 forfattere av denne artikkelen] (2019). Modis snowline elevation changes during snowmelt runoff events in Europe. Journal of Hydrology and Hydromechanics. ISSN 0042-790X. 67(1), s. 101–109. doi: 10.2478/johh-2018-0011. Fulltekst i vitenarkiv Vis sammendrag

  This study evaluates MODIS snow cover characteristics for large number of snowmelt runoff events in 145 catchments from 9 countries in Europe. The analysis is based on open discharge daily time series from the Global Runoff Data Center database and daily MODIS snow cover data. Runoff events are identified by a base flow separation approach. The MODIS snow cover characteristics are derived from Terra 500 m observations (MOD10A1 dataset, V005) in the period 2000–2015 and include snow cover area, cloud coverage, regional snowline elevation (RSLE) and its changes during the snowmelt runoff events. The snowmelt events are identified by using estimated RSLE changes during a runoff event. The results indicate that in the majority of catchments there are between 3 and 6 snowmelt runoff events per year. The mean duration between the start and peak of snowmelt runoff events is about 3 days and the proportion of snowmelt events in all runoff events tends to increase with the maximum elevation of catchments. Clouds limit the estimation of snow cover area and RSLE, particularly for dates of runoff peaks. In most of the catchments, the median of cloud coverage during runoff peaks is larger than 80%. The mean minimum RSLE, which represents the conditions at the beginning of snowmelt events, is situated approximately at the mean catchment elevation. It means that snowmelt events do not start only during maximum snow cover conditions, but also after this maximum. The mean RSLE during snowmelt peaks is on average 170 m lower than at the start of the snowmelt events, but there is a large regional variability.

• Mesquita, Michel d. S.; Orsolini, Yvan; Pal, Indrani; Veldore, Vidyunmala; Li, Lu & Raghavan, Krishnan [Vis alle 10 forfattere av denne artikkelen] (2019). Challenges in forecasting water resources of the Indus River basin: Lessons from the analysis and modeling of atmospheric and hydrological processes. I Khan, Sadiq & Adams III, Thomas (Red.), Indus River basin. Water security and sustainability.. Elsevier. ISSN 9780128127827. s. 57–83. doi: https:/doi.org/10.1016/B978-0-12-812782-7.00003-5.
• Teweldebrhan, Aynom Tesfay; Burkhart, John; Schuler, Thomas & Xu, Chong-Yu (2019). Improving the Informational Value of MODIS Fractional Snow Cover Area Using Fuzzy Logic Based Ensemble Smoother Data Assimilation Frameworks. Remote Sensing. ISSN 2072-4292. 11(1). doi: 10.3390/rs11010028. Fulltekst i vitenarkiv
• Wang, Tao; Liu, Dan; Piao, Shilong; Wang, Yilong; Wang, Xiaoyi & Guo, Hui [Vis alle 19 forfattere av denne artikkelen] (2018). Emerging negative impact of warming on summer carbon uptake in northern ecosystems. Nature Communications. ISSN 2041-1723. 9. doi: 10.1038/s41467-018-07813-7. Fulltekst i vitenarkiv
• Matt, Felix Nikolaus & Burkhart, John (2018). Assessing Satellite-Derived Radiative Forcing From Snow Impurities Through Inverse Hydrologic Modeling. Geophysical Research Letters. ISSN 0094-8276. 45(8), s. 3531–3541. doi: 10.1002/2018GL077133.
• Teweldebrhan, Aynom Tesfay; Burkhart, John & Schuler, Thomas (2018). Parameter uncertainty analysis for an operational hydrological model using residual-based and limits of acceptability approaches. Hydrology and Earth System Sciences (HESS). ISSN 1027-5606. 22(9), s. 5021–5039. doi: 10.5194/hess-22-5021-2018. Fulltekst i vitenarkiv
• Matt, Felix Nikolaus; Burkhart, John & Pietikainen, Joni-Pekka (2018). Modelling hydrologic impacts of light absorbing aerosol deposition on snow at the catchment scale. Hydrology and Earth System Sciences (HESS). ISSN 1027-5606. 22(1), s. 179–201. doi: 10.5194/hess-22-179-2018. Fulltekst i vitenarkiv
• Eriksrød, Jon Håvard; Kjelgård, Kristian Gjertsen; Tømmer, Mathias; Burkhart, John & Lande, Tor Sverre (2017). Bi-static environmental SAR radar imager. I Jari, Nurmi (Red.), 2017 IEEE Nordic Circuits and Systems Conference (NORCAS): NORCHIP and International Symposium of System-on-Chip (SoC). IEEE conference proceedings. ISSN 978-1-5386-2844-7. doi: 10.1109/NORCHIP.2017.8124979.
• McConnell, Joseph R.; Burke, Andrea; Dunbar, Nelia W; Kohler, Peter; Thomas, Jennie L. & Arienzo, Monica M [Vis alle 29 forfattere av denne artikkelen] (2017). Synchronous volcanic eruptions and abrupt climate change ~17.7 ka plausibly linked by stratospheric ozone depletion. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 114(38), s. 10035–10040. doi: 10.1073/pnas.1705595114.
• Burkhart, John; Kylling, Arve; Schaaf, Crystal B.; Wang, Zhuosen; Bogren, Wiley Steven & Storvold, Rune [Vis alle 9 forfattere av denne artikkelen] (2017). Unmanned aerial system nadir reflectance and MODIS nadir BRDF-adjusted surface reflectances intercompared over Greenland. The Cryosphere. ISSN 1994-0416. 11(4), s. 1575–1589. doi: 10.5194/tc-11-1575-2017. Fulltekst i vitenarkiv
• Piao, Shilong; Liu, Zhuo; Wang, Tao; Peng, Shushi; Ciais, Philippe & Huang, Mengtian [Vis alle 22 forfattere av denne artikkelen] (2017). Weakening temperature control on the interannual variations of spring carbon uptake across northern lands. Nature Climate Change. ISSN 1758-678X. 7(5), s. 359–363. doi: 10.1038/nclimate3277.
• Paliwal, Umed; Sharma, Mukesh & Burkhart, John (2016). Monthly and spatially resolved black carbon emission inventory of India: uncertainty analyses. Atmospheric Chemistry and Physics Discussions (ACPD). ISSN 1680-7367. 2016, s. 1–32. doi: 10.5194/acp-2015-978.
• Paliwal, Umed; Sharma, Mukesh & Burkhart, John (2016). Monthly and spatially resolved black carbon emission inventory of India: Uncertainty analysis. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 16(19), s. 12457–12476. doi: 10.5194/acp-16-12457-2016. Fulltekst i vitenarkiv
• Uttal, Taneil; Starkweather, Sandra; Drummond, James R.; Vihma, Timo Pekka; Makshtas, Alexander P. & Darby, Lisa S. [Vis alle 54 forfattere av denne artikkelen] (2016). International arctic systems for observing the atmosphere: An International Polar Year Legacy Consortium. Bulletin of The American Meteorological Society - (BAMS). ISSN 0003-0007. 97(6), s. 1033–1056. doi: 10.1175/BAMS-D-14-00145.1.
• Hegdahl, Trine Jahr; Tallaksen, Lena M.; Engeland, Kolbjørn; Burkhart, John & Xu, Chong-Yu (2016). Discharge sensitivity to snowmelt parameterization: A case study for Upper Beas basin in Himachal Pradesh, India. Hydrology Research. ISSN 1998-9563. 47(4), s. 683–700. doi: 10.2166/nh.2016.047.
• Fibiger, Dorothy L.; Dibb, Jack E.; Chen, Dexian; Thomas, Jennie L.; Burkhart, John & Huey, Lewis Gregory [Vis alle 7 forfattere av denne artikkelen] (2016). Analysis of nitrate in the snow and atmosphere at Summit, Greenland: Chemistry and transport. Journal of Geophysical Research (JGR): Atmospheres. ISSN 2169-897X. 121(9), s. 5010–5030. doi: 10.1002/2015JD024187.
• Bogren, Wiley Steven; Burkhart, John & Kylling, Arve (2016). Tilt error in cryospheric surface radiation measurements at high latitudes: a model study. The Cryosphere. ISSN 1994-0416. 10(2), s. 613–622. doi: 10.5194/tc-10-613-2016. Fulltekst i vitenarkiv
• Kramer, L.J; Helmig, Detlev; Burkhart, John; Stohl, Andreas; Oltmans, S. & Honrath, Richard E. (2015). Seasonal variability of atmospheric nitrogen oxides and non-methane hydrocarbons at the GEOSummit station, Greenland. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 15(12), s. 6827–6849. doi: 10.5194/acp-15-6827-2015. Fulltekst i vitenarkiv
• Law, Katharine S.; Stohl, Andreas; Quinn, Patricia K.; Brock, Charles A.; Burkhart, John & Paris, Jean-Daniel [Vis alle 15 forfattere av denne artikkelen] (2014). Arctic air pollution: New insights from POLARCAT-IPY. Bulletin of The American Meteorological Society - (BAMS). ISSN 0003-0007. 95(12), s. 1873–1895. doi: 10.1175/BAMS-D-13-00017.1.
• Pandolfi, Marco; Querol, Xavier; Alastuey, Andrés; Jiḿenez, José Luis González; Jorba, Oriol & Day, Douglas A. [Vis alle 29 forfattere av denne artikkelen] (2014). Effects of sources and meteorology on particulate matter in the Western Mediterranean Basin: An overview of the DAURE campaign. Journal of Geophysical Research (JGR): Biogeosciences. ISSN 2169-8953. 119(8), s. 4978–5010. doi: 10.1002/2013JD021079.
• Brioude, J; Arnold, D; Stohl, Andreas; Cassiani, Massimo; Morton, D & Seibert, P [Vis alle 14 forfattere av denne artikkelen] (2013). The Lagrangian particle dispersion model FLEXPART-WRF version 3.1. Geoscientific Model Development. ISSN 1991-959X. 6(6), s. 1889–1904. doi: 10.5194/gmd-6-1889-2013. Fulltekst i vitenarkiv Vis sammendrag

  The Lagrangian particle dispersion model FLEXPART was originally designed for calculating long-range and mesoscale dispersion of air pollutants from point sources, such that occurring after an accident in a nuclear power plant. In the meantime, FLEXPART has evolved into a comprehensive tool for atmospheric transport modeling and analysis at different scales. A need for further multiscale modeling and analysis has encouraged new developments in FLEXPART. In this paper, we present a FLEXPART version that works with the Weather Research and Forecasting (WRF) mesoscale meteorological model. We explain how to run this new model and present special options and features that differ from those of the preceding versions. For instance, a novel turbulence scheme for the convective boundary layer has been included that considers both the skewness of turbulence in the vertical velocity as well as the vertical gradient in the air density. To our knowledge, FLEXPART is the first model for which such a scheme has been developed. On a more technical level, FLEXPART-WRF now offers effective parallelization, and details on computational performance are presented here. FLEXPART-WRF output can either be in binary or Network Common Data Form (NetCDF) format, both of which have efficient data compression. In addition, test case data and the source code are provided to the reader as a Supplement. This material and future developments will be accessible at http://www.flexpart.eu.

• Yasunari, Teppei J.; Stohl, Andreas; Hayano, Ryugo S.; Burkhart, John; Eckhardt, Sabine & Yasunari, Tetsuzo (2013). Correction for Yasunari et al., Cesium-137 deposition and contamination of Japanese soils due to the Fukushima nuclear accident. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 110, s. 7525–7528. doi: 10.1073/pnas.1301231110.
• Bates, Timothy S.; Quinn, Patricia K.; Johnson, James E.; Corless, Andrew; Brechtel, Fred J. & Stalin, Scott E. [Vis alle 8 forfattere av denne artikkelen] (2013). Measurements of atmospheric aerosol vertical distributions above Svalbard, Norway, using unmanned aerial systems (UAS). Atmospheric Measurement Techniques. ISSN 1867-1381. 6(8), s. 2115–2120. doi: 10.5194/amt-6-2115-2013. Fulltekst i vitenarkiv
• Crumeyrolle, Suzanne; Schwarzenboeck, Alfons; Roger, Jean-Claude; Sellegri, Karine; Burkhart, John & Stohl, Andreas [Vis alle 14 forfattere av denne artikkelen] (2013). Overview of aerosol properties associated with air masses sampled by the ATR-42 during the EUCAARI campaign (2008). Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 13(9), s. 4877–4893. doi: 10.5194/acp-13-4877-2013. Fulltekst i vitenarkiv
• Van Dam, Brie; Helmig, Detlev; Burkhart, John; Obrist, Daniel & Oltmans, Samuel J. (2013). Springtime boundary layer O-3 and GEM depletion at Toolik Lake, Alaska. Journal of Geophysical Research (JGR): Atmospheres. ISSN 2169-897X. 118(8), s. 3382–3391. doi: 10.1002/jgrd.50213.
• Cristofanelli, P.; Fierli, F.; Marinoni, A.; Calzolari, F.; Duchi, R. & Burkhart, John [Vis alle 10 forfattere av denne artikkelen] (2013). Influence of biomass burning and anthropogenic emissions on ozone, carbon monoxide and black carbon at the Mt. Cimone GAW-WMO global station (Italy, 2165 m a.s.l.). Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 13(1), s. 15–30. doi: 10.5194/acp-13-15-2013. Fulltekst i vitenarkiv
• Freutel, F.; Schneider, J.; Drewnick, F.; von der Weiden-Reinmuller, S. L.; Crippa, M. & Prévôt, A. S. H. [Vis alle 23 forfattere av denne artikkelen] (2013). Aerosol particle measurements at three stationary sites in the megacity of Paris during summer 2009: meteorology and air mass origin dominate aerosol particle composition and size distribution. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 13(2), s. 933–959. doi: 10.5194/acp-13-933-2013. Fulltekst i vitenarkiv
• Ubl, Sandy; Scheringer, Martin; Stohl, Andreas; Burkhart, John & Hungerbuhler, Konrad (2012). Primary source regions of polychlorinated biphenyls (PCBs) measured in the Arctic. Atmospheric Environment. ISSN 1352-2310. 62, s. 391–399. doi: 10.1016/j.atmosenv.2012.07.061.
• Pikridas, Michalis; Riipinen, Ilona; Hildebrandt, Lea; Kostenidou, Evangelia; Manninen, Hanna & Mihalopoulos, Nikos [Vis alle 11 forfattere av denne artikkelen] (2012). New particle formation at a remote site in the eastern Mediterranean. Journal of Geophysical Research (JGR): Atmospheres. ISSN 2169-897X. 117. doi: 10.1029/2012JD017570.
• Sjostedt, Steven J.; Leaitch, W. Richard; Levasseur, Maurice; Scarratt, Michael; Michaud, Sonia & Motard-Côté, Jessie [Vis alle 8 forfattere av denne artikkelen] (2012). Evidence for the uptake of atmospheric acetone and methanol by the Arctic Ocean during late summer DMS-Emission plumes. Journal of Geophysical Research (JGR): Atmospheres. ISSN 2169-897X. 117. doi: 10.1029/2011JD017086.
• Quennehen, Boris; Schwarzenboeck, Alfons; Matsuki, Atushi; Burkhart, John; Stohl, Andreas & Ancellet, Gerard [Vis alle 7 forfattere av denne artikkelen] (2012). Anthropogenic and forest fire pollution aerosol transported to the Arctic: observations from the POLARCAT-France spring campaign. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 12(14), s. 6437–6454. doi: 10.5194/acp-12-6437-2012. Fulltekst i vitenarkiv
• Stohl, Andreas; Seibert, P.; Wotawa, G; Arnold, D.; Burkhart, John Faulkner & Eckhardt, Sabine [Vis alle 9 forfattere av denne artikkelen] (2012). Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Dai-ichi nuclear power plant: determination of the source term, atmospheric dispersion, and deposition. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 12(5), s. 2313–2343. doi: 10.5194/acp-12-2313-2012. Fulltekst i vitenarkiv
• Blechschmidt, Anne-Marlene; Kristjansson, Jon Egill; Ólafsson, Haraldur; Burkhart, John; Hodnebrog, Øivind & Rosenberg, P.D. (2012). Aircraft-based observations and high-resolution simulations of an Icelandic dust storm. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 12(22), s. 10649–10666. doi: 10.5194/acp-12-10649-2012. Fulltekst i vitenarkiv Vis sammendrag

  The first aircraft-based observations of an Icelandic dust storm are presented. The measurements were carried out over the ocean near Iceland's south coast in February 2007. This dust event occurred in conjunction with an easterly barrier jet of more than 30 m s−1. The aircraft measurements show high particle mass mixing ratios in an area of low wind speeds in the wake of Iceland near the coast, decreasing abruptly towards the jet. Simulations from the Weather Research and Forecasting Model coupled with Chemistry (WRF/Chem) indicate that the measured high mass mixing ratios and observed low visibility inside the wake are due to dust transported from Icelandic sand fields towards the ocean. This is confirmed by meteorological station data. Glacial outwash terrains located near the Mýrdalsjökull glacier are among simulated dust sources. Sea salt aerosols produced by the impact of strong winds on the ocean surface started to dominate as the aircraft flew away from Iceland into the jet. The present results support recent studies which suggest that Icelandic deserts should be considered as important dust sources in global and regional climate models.

• Minguillón, M. C.; Perron, N.; Querol, X.; Szidat, S.; Fahrni, S. M. & Alastuey, A [Vis alle 30 forfattere av denne artikkelen] (2011). Fossil versus contemporary sources of fine elemental and organic carbonaceous particulate matter during the DAURE campaign in Northeast Spain. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(23), s. 12067–12084. doi: 10.5194/acp-11-12067-2011. Fulltekst i vitenarkiv Vis sammendrag

  We present results from the international field campaign DAURE (Determination of the sources of atmospheric Aerosols in Urban and Rural Environments in the Western Mediterranean), with the objective of apportioning the sources of fine carbonaceous aerosols. Submicron fine particulate matter (PM1) samples were collected during February–March 2009 and July 2009 at an urban background site in Barcelona (BCN) and at a forested regional background site in Montseny (MSY). We present radiocarbon (14C) analysis for elemental and organic carbon (EC and OC) and source apportionment for these data. We combine the results with those from component analysis of aerosol mass spectrometer (AMS) measurements, and compare to levoglucosan-based estimates of biomass burning OC, source apportionment of filter data with inorganic composition + EC + OC, submicron bulk potassium (K) concentrations, and gaseous acetonitrile concentrations. At BCN, 87 % and 91 % of the EC on average, in winter and summer, respectively, had a fossil origin, whereas at MSY these fractions were 66 % and 79 %. The contribution of fossil sources to organic carbon (OC) at BCN was 40 % and 48 %, in winter and summer, respectively, and 31 % and 25 % at MSY. The combination of results obtained using the 14C technique, AMS data, and the correlations between fossil OC and fossil EC imply that the fossil OC at Barcelona is ∼47 % primary whereas at MSY the fossil OC is mainly secondary (∼85 %). Day-to-day variation in total carbonaceous aerosol loading and the relative contributions of different sources predominantly depended on the meteorological transport conditions. The estimated biogenic secondary OC at MSY only increased by ∼40 % compared to the order-of-magnitude increase observed for biogenic volatile organic compounds (VOCs) between winter and summer, which highlights the uncertainties in the estimation of that component. Biomass burning contributions estimated using the 14C technique ranged from similar to slightly higher than when estimated using other techniques, and the different estimations were highly or moderately correlated. Differences can be explained by the contribution of secondary organic matter (not included in the primary biomass burning source estimates), and/or by an overestimation of the biomass burning OC contribution by the 14C technique if the estimated biomass burning EC/OC ratio used for the calculations is too high for this region. Acetonitrile concentrations correlate well with the biomass burning EC determined by 14C. K is a noisy tracer for biomass burning.

• Yttri, Karl Espen; Simpson, D.; Nøjgaard, J.K.; Kristensen, K.; Genberg, J. & Stenström, K. [Vis alle 17 forfattere av denne artikkelen] (2011). Source apportionment of the summer time carbonaceous aerosol at Nordic rural background sites. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(24), s. 13339–13357. doi: 10.5194/acp-11-13339-2011. Fulltekst i vitenarkiv
• Roiger, A.; Schlager, H.; Schafler, A.; Huntrieser, H; Scheibe, M & Aufmhoff, H. [Vis alle 14 forfattere av denne artikkelen] (2011). In-situ observation of Asian pollution transported into the Arctic lowermost stratosphere. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(21), s. 10975–10994. doi: 10.5194/acp-11-10975-2011. Fulltekst i vitenarkiv
• Yasunari, Teppei J.; Stohl, Andreas; Hayano, Ryugo S.; Burkhart, John Faulkner; Eckhardt, Sabine & Yasunari, Tetsuzo (2011). Cesium-137 deposition and contamination of Japanese soils due to the Fukushima nuclear accident. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 108(49), s. 19530–19534. doi: 10.1073/pnas.1112058108. Fulltekst i vitenarkiv
• Chang, R. Y.-W.; Leck, C.; Graus, M.; Müller, M; Paatero, J. & Burkhart, John Faulkner [Vis alle 14 forfattere av denne artikkelen] (2011). Aerosol composition and sources in the central Arctic Ocean during ASCOS. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(20), s. 10619–10636. doi: 10.5194/acp-11-10619-2011. Fulltekst i vitenarkiv
• Kulmala, Markku; Asmi, Ari; Lappalainen, H. K.; Baltensperger, Urs; Brenguier, Jean-Louis & Facchini, Cristina [Vis alle 125 forfattere av denne artikkelen] (2011). General overview: European Integrated project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) - integrating aerosol research from nano to global scales. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(24), s. 13061–13143. doi: 10.5194/acp-11-13061-2011. Fulltekst i vitenarkiv
• Schmale, J.; Schneider, J.; Ancellet, G.; Quennehen, B.; Stohl, Andreas & Sodemann, Harald [Vis alle 12 forfattere av denne artikkelen] (2011). Source identification and airborne chemical characterisation of aerosol pollution from long-range transport over Greenland during POLARCAT summer campaign 2008. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(19), s. 10097–10123. doi: 10.5194/acp-11-10097-2011. Fulltekst i vitenarkiv Vis sammendrag

  We deployed an aerosol mass spectrometer during the POLARCAT (Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, of Climate, Chemistry, Aerosols, and Transport) summer campaign in Greenland in June/July 2008 on the research aircraft ATR-42. Online size resolved chemical composition data of submicron aerosol were collected up to 7.6 km altitude in the region 60 to 71° N and 40 to 60° W. Biomass burning (BB) and fossil fuel combustion (FF) plumes originating from North America, Asia, Siberia and Europe were sampled. Transport pathways of detected plumes included advection below 700 hPa, air mass uplifting in warm conveyor belts, and high altitude transport in the upper troposphere. By means of the Lagrangian particle dispersion model FLEXPART, trace gas analysis of O3 and CO, particle size distributions and aerosol chemical composition 48 pollution events were identified and classified into five chemically distinct categories. Aerosol from North American BB consisted of 22% particulate sulphate, while with increasing anthropogenic and Asian influence aerosol in Asian FF dominated plumes was composed of up to 37% sulphate category mean value. Overall, it was found that the organic matter fraction was larger (85%) in pollution plumes than for background conditions (71%). Despite different source regions and emission types the particle oxygen to carbon ratio of all plume classes was around 1 indicating low-volatility highly oxygenated aerosol. The volume size distribution of out-of-plume aerosol showed markedly smaller modes than all other distributions with two Aitken mode diameters of 24 and 43 nm and a geometric standard deviation σg of 1.12 and 1.22, respectively, while another very broad mode was found at 490 nm (σg = 2.35). Nearly pure BB particles from North America exhibited an Aitken mode at 66 nm (σg = 1.46) and an accumulation mode diameter of 392 nm (σg = 1.76). An aerosol lifetime, including all processes from emission to detection, in the range between 7 and 11 days was derived for North American emissions.

• Stutz, J.; Thomas, J.L.; Hurlock, S.C.; Schneider, M.; von Glasow, R. & Piot, M. [Vis alle 11 forfattere av denne artikkelen] (2011). Longpath DOAS observations of surface BrO at Summit, Greenland. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(18), s. 9899–9910. doi: 10.5194/acp-11-9899-2011. Fulltekst i vitenarkiv
• Merlaud, A.; Van Roozendael, M.; Theys, N.; Fayt, C.; Hermans, C. & Quennehen, B. [Vis alle 13 forfattere av denne artikkelen] (2011). Airborne DOAS measurements in Arctic: vertical distributions of aerosol extinction coefficient and NO2 concentration. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(17), s. 9219–9236. doi: 10.5194/acp-11-9219-2011. Fulltekst i vitenarkiv
• Vay, S. A.; Choi, Y.; Vadrevu, K.P.; Blake, Donald R.; Tyler, S. C. & Wisthaler, A [Vis alle 14 forfattere av denne artikkelen] (2011). Patterns of CO2 and radiocarbon across high northern latitudes during International Polar Year 2008. Journal of Geophysical Research (JGR): Atmospheres. ISSN 2169-897X. 116. doi: 10.1029/2011JD015643.
• Hamburger, T.; McMeeking, G.; Minikin, A; Birmili, W; Dall'Osto, M & O'Dowd, C [Vis alle 16 forfattere av denne artikkelen] (2011). Overview of the synoptic and pollution situation over Europe during the EUCAARI-LONGREX field campaign. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(3), s. 1065–1082. doi: 10.5194/acp-11-1065-2011. Fulltekst i vitenarkiv
• Siegfried, Matthew R.; Hawley, Robert L. & Burkhart, John Faulkner (2011). High-Resolution Ground-Based GPS Measurements Show Intercampaign Bias in ICESat Elevation Data Near Summit, Greenland. IEEE Transactions on Geoscience and Remote Sensing. ISSN 0196-2892. 49(9), s. 3393–3400. doi: 10.1109/TGRS.2011.2127483.
• Lance, S; Shupe, M.D.; Feingold, G; Brock, CA; Cozic, J & Holloway, J.S. [Vis alle 16 forfattere av denne artikkelen] (2011). Cloud condensation nuclei as a modulator of ice processes in Arctic mixed-phase clouds. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(15), s. 8003–8015. doi: 10.5194/acp-11-8003-2011. Fulltekst i vitenarkiv
• Hyvarinen, A.-P.; Kolmonen, P; Kerminen, V.-M.; Virkkula, A.; Leskinen, A. & Komppula, M. [Vis alle 14 forfattere av denne artikkelen] (2011). Aerosol black carbon at five background measurement sites over Finland, a gateway to the Arctic. Atmospheric Environment. ISSN 1352-2310. 45(24), s. 4042–4050. doi: 10.1016/j.atmosenv.2011.04.026.
• Sodemann, Harald; Pommier, M; Arnold, SR; Monks, SA; Stebel, Kerstin & Burkhart, John Faulkner [Vis alle 15 forfattere av denne artikkelen] (2011). Episodes of cross-polar transport in the Arctic troposphere during July 2008 as seen from models, satellite, and aircraft observations. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 11(8), s. 3631–3651. doi: 10.5194/acp-11-3631-2011. Fulltekst i vitenarkiv
• Hirdman, David Arne; Burkhart, John Faulkner; Sodemann, Harald; Eckhardt, Sabine; Jefferson, Anne & Quinn, Patricia K. [Vis alle 9 forfattere av denne artikkelen] (2010). Long-term trends of black carbon and sulphate aerosol in the Arctic: changes in atmospheric transport and source region emissions. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 10, s. 9351–9368. doi: 10.5194/acp-10-9351-2010. Fulltekst i vitenarkiv
• Hirdman, David Arne; Sodemann, Harald; Eckhardt, Sabine; Burkhart, John Faulkner; Jefferson, Anne & Mefford, Thomas [Vis alle 10 forfattere av denne artikkelen] (2010). Source identification of short-lived air pollutants in the Arctic using statistical analysis of measurement data and particle dispersion model output. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 10(2), s. 669–693. doi: 10.5194/acp-10-669-2010. Fulltekst i vitenarkiv
• Pikridas, Michalis; Bougiatioti, Aikaterini; Hildebrandt, Lea; Engelhart, Gabriella J.; Kostenidou, Evangelia & Mohr, Claudia [Vis alle 18 forfattere av denne artikkelen] (2010). The Finokalia Aerosol Measurement Experiment – 2008 (FAME-08): an overview. Atmospheric Chemistry and Physics (ACP). ISSN 1680-7316. 10(14), s. 6793–6806. doi: 10.5194/acp-10-6793-2010. Fulltekst i vitenarkiv

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• Filhol, Simon; Lefeuvre, Pierre-Marie; Burkhart, John Faulkner; Schuler, Thomas Vikhamar; Gallet, Jean-Charles & Hulth, John [Vis alle 7 forfattere av denne artikkelen] (2023). Development and Deployment of Wireless Sensor Networks on Arctic Glaciers.
• Silantyeva, Olga; Bhattarai, Bikas Chandra; Tallaksen, Lena M.; Burkhart, John Faulkner; Skavhaug, Ola & Helset, Sigbjørn (2021). Modeling Sensitivity To Mesh Size And Shape: A Case Study At Central Himalayan Catchment Revealing Importance Of Regional Dataset. Vis sammendrag

  The complex terrain, high seasonal variability, complexity in precipitation patterns and cold region hydrology at Budhi-Gandaki catchment in central Himalaya, Nepal, presents a challenge for hydrological modeling. Regional or local forcing data, especially with high spatial resolution is preferred over coarser global dataset. However, such data is not always available. The Budhi-Gandaki catchment is subject to significant hydropower development, so accurate discharge simulation is important. Shyft is a novel hydrologic modeling software for streamflow forecasting targeted for use in hydropower production environments and research (Burkhart et al, 2021). It allows easy manipulation with configurations, which is a great tool in decision-making processes in the power production chain. The new functionality of Shyft.hydrology allows capturing of detailed terrain topography using triangular irregular networks (tin) and “on the fly” slope and aspect correction of radiation forcing. We compare discharge simulations using two different forcing datasets: WFDEI global dataset (0.5o x 0.5o) and HI-AWARE regional dataset (5x5 km precipitation and temperature) in both a grid and tin-based configurations. Simulated discharge is compared to observed discharge for ten-year period (2000-2010) using two performance measures, Nash- Sutcliffe efficiency (NSE) and Kling-Gupta efficiency (KGE). We show that the regional dataset combined with a tin configuration performs better than using a rectangular grid resolution, both in terms of NSE and KGE. Furthermore, correcting radiation for slope and aspect at each cell improves the resultant NSE and KGE even more. However, for the global dataset a configuration based on tin performs worse than grid, which is partly attributed to the complexity of the precipitation distribution over the catchment area. One WFDEI grid cell covers the whole catchment, so it is only represented by one precipitation value, which does not allow the interpolation routines in the Shyft.hydrology to separate between windward and leeward areas. However, for less complex terrain and precipitation patterns, like in the Marsyangdi catchment, studied previously (Bhattarai et all, 2020), good results obtained even with the coarse resolution WFDEI dataset. Here introducing a tin configurations improved agreement between simulated and observed discharge as compared to using a rectangular grid. We conclude on the advantages of using a tin-based configurations for water planning in hydropower production in the region. This work contributes to LATICE (Land Atmosphere Interactions in Cold Environments) project at the University of Oslo Keywords: Central Himalaya; Budhi-Gandaki; Hi-AWARE; Shyft; TIN; Discharge simulation; References 1. Burkhart, J. F., Matt, F. N., Helset, S., Sultan Abdella, Y., Skavhaug, O., and Silantyeva, O.: Shyft v4.8: a framework for uncertainty assessment and distributed hydrologic modeling for operational hydrology, Geosci. Model Dev., 14, 821–842, https://doi.org/10.5194/gmd-14-821-2021, 2021. 2. Bhattarai, B. C., Silantyeva, O., Teweldebrhan, A. T., Helset, S., Skavhaug, O., and Burkhart, J. F.: Impact of Catchment Discretization and Imputed Radiation on Model Response: A Case Study from Central Himalayan Catchment, Water, 12, 2020.

• Silantyeva, Olga; Burkhart, John Faulkner; Bhattarai, Bikas Chandra; Skavhaug, Ola & Helset, Sigbjørn (2020). Operational hydrology in highly steep areas: evaluation of tin-based toolchain. Vis sammendrag

  Triangular Irregular Network (TIN) is known to be an efficient way to represent surface topog- raphy (Marsh et al. 2018). However, little attention has been given to assess direct benefits of the TIN-based terrain representation in operational hydrology. We connect Shyft-hydrology, a part of Shyft open-source project dedicated to distributed hydrologic modelling in operational environment, with Rasputin software intended for conversion of digital elevation models into simplified triangular meshes. Shyft is known for its high flexibility: the framework lets researcher test different function- ing hypothesis with very little programming effort. We implemented new routine in Shyft-hydrology, which allows translation of solar radiation onto inclined surfaces based on (Allen et al. 2006). Thus, Shyft and Rasputin is a unique toolchain to study impact of hillslope variations in solar radiation onto snowmelt, evapotranspiration and discharge simulation. We conducted several experiments on subcatchments of Narayani river located in Central Nepal. This area is known to be very steep, with meteorological stations, located mainly in the low-land. The re-analysis data for the area is coarse and prone to different kind of issues (Bhattarai et al 2020). The outcomes are promising: tin-based solution outperfoms regular grid, when running with Shyft-hydrology model most used in the operations. The new model with translated radiation also works well, giving us no decrease in performance of discharge simulations, but some more insights in snow modelling. We clearly see, what we expect from observations: sunny slopes melt earlier while shady ones keep snow for longer periods. Acknowledgments. This project contributes to LATICE (Land Atmosphere Interaction in Cold Environments) initiative at the University of Oslo. References Marsh, C. B., Spiteri, R. J., Pomeroy, J. W., and Wheater, H. S.: Multi-objective unstructured triangular mesh generation for use in hydro- logical and land surface models, Computers and Geo- sciences, 119, 4967, 2018. Richard G. Allen, Ricardo Trezza, and Masahiro Tasumi. Analytical integrated functions for daily solar radiation on slopes. Agricultural and Forest Meteorology, 139:5573, 2006. Bhattarai, B. C., Burkhart, J. F., Tallaksen, L. M., Xu, C.-Y., and Matt, F. N.: Evaluation of forcing datasets for hydropower inflow simulation in Nepal, Accepted for publication. Hydrology research, 2020 1

• Pisso, Ignacio; Sollum, Espen; Grythe, Henrik; Kristiansen, Nina Iren; Cassiani, Massimo & Eckhardt, Sabine [Vis alle 21 forfattere av denne artikkelen] (2020). The Lagrangian particle dispersion model FLEXPART version 10.4.
• Silantyeva, Olga; Burkhart, John; Tallaksen, Lena M.; Helset, Sigbjørn & Skavhaug, Ola (2019). Shyft - Hydrologic Forecasting Toolbox: current state and future work.
• Silantyeva, Olga; Tallaksen, Lena M.; Burkhart, John; Skavhaug, Ola & Helset, Sigbjørn (2019). Analysis on the added value of accounting for slope/aspect and shading effects in hydrologic simulations. Vis sammendrag

  Radiation flux is a major component of earth’s energy balance. It is the driving factor for various processes withing the earth’s atmosphere and surface. However, the precise measurement of insolation is still subject to errors due to number of effects such as clouds and terrain shading. At regional scale the main issues is the existence and quality of radiation measurements in mountainous areas. The observational errors typically propagate through simulations leading to less accurate predictions of events such as snowmelt. We further develop SHyFT framework (https://github.com/statkraft/shyft), which is an opera- tional tool for distributed hydrologic modeling. Our current progress accounts for terrain topography. The new part of the tool allows detailed capture of topography and simulates slope/aspect and shad- ing effects. The radiation flux is translated onto inclined surfaces based on the method developed by [Allen et al., 2006]. The shading effects are added as a part of new triangulation tool (https://github.com/expertanalytics/rasputin). We expect that new functionality will help us investigate the hypothesis formulated in [Fan et al., 2019] that in energy-limited areas insolation contrast between sunny and shady slopes impacts water and vegetation. In order to conclude about the added value of the new methods at regional scale we are going to simulate number of local cases to asses impact on snowmelt and vegetation. The formulated results will be interesting for water planning in hydropower production as well as for weather predicting specialists. This work is a part of LATICE (Land Atmosphere Interaction in Cold Environments) project at the University of Oslo. References Richard G. Allen, Ricardo Trezza, and Masahiro Tasumi. Analytical integrated functions for daily solar radiation on slopes. Agricultural and Forest Meteorology, 139:55–73, 2006. Y. Fan et al. Hillslope hydrology in global change research and earth system modeling. Water Resources Research, 55(2), 2019.

• Silantyeva, Olga; Tallaksen, Lena M. & Burkhart, John (2019). Understanding terrain topography impact on snowmelt at catchment scale. Vis sammendrag

  The work by [Fan et.al., 2019] calls for model experiments to evaluate the major hypothesis that energy or water-limited regions are largely controlled by hillslopes. However, the meteorological data in mountainous areas lacks accuracy due to sparse station network and coarse re-analysis grids (for example, high-resolution senorge data is only 1km). Simulation tools that model hydrologic processes at local scales require ways to overcome the lack of accuracy in the observational data, particular at high elevations. SHyFT is a tool for distributed hydrologic modeling, which has demonstrated a high potential in the ability to model stream flow in complex and data sparse regions [Burkhart et al., 2016]. Steps are also taken to further account for hillslope-scale terrain structures carefully. This new functionality allows downscaling and translating radiation measurements or re-analysis data onto inclined surfaces improving the predictive power of the model. Based on the SHyFT framework we are analyzing the importance of topographic details such as slope/aspect and shading on predicting snowmelt and vegetation in northern latitudes, which are characterized by energy-limited complex terrain. Observations inform us that slope/aspect and shading effects in mountainous regions impact snowmelt: sunny slopes melt earlier while shady ones store snow for longer periods. Our framework provides a unique capability to directly incorporate these effects online within the hydrologic computation, and we will further evaluate whether the aforementioned hypothesis is accurately characterized with this new functionality for operational cases. Further, we will assess whether there is a direct benefit to hydrologic simulation. This project contributes to LATICE (Land Atmosphere Interaction in Cold Environments) initiative at the University of Oslo. References J. F. Burkhart, S. Helset, Y. S. Abdella, and G. Lappegard. Operational research:evaluating multi- model implementations for 24/7 runtime environment. American Geophysical Union, Fall General Assembly 2016, Abstract Id. H51F-1541, 2016. Y. Fan et al. Hillslope hydrology in global change research and earth system modeling. Water- Resources Research, 55(2), 2019.

• Teweldebrhan, Aynom Tesfay; Burkhart, John; Schuler, Thomas & Hjorth-Jensen, Morten (2019). Application of machine learning emulators in parameter identification for a distributed hydrological model.
• Teweldebrhan, Aynom Tesfay; Burkhart, John; Schuler, Thomas & Xu, Chong-Yu (2019). Assimilation of MODIS fractional snow cover area into a hydrological model using fuzzy-logic based ensemble smoother data assimilation frameworks.
• Teweldebrhan, Aynom Tesfay; Burkhart, John; Schuler, Thomas & Xu, Chong-Yu (2019). Snow data assimilation into a hydrological model using fuzzy logic based ensemble smoothers.
• Teweldebrhan, Aynom Tesfay; Burkhart, John; Schuler, Thomas & Xu, Chong-Yu (2019). Fuzzy-logic based ensemble smoother data assimilation frameworks for improving the informational value of the assimilated data.
• Teweldebrhan, Aynom Tesfay; Burkhart, John & Schuler, Thomas (2019). Balancing between type I and type II errors in testing hydrological models as hypotheses of catchment behaviour .
• Matt, Felix Nikolaus; Magnusson, Jan Olof; Nævdal, Geir; Winstral, Adam & Burkhart, John (2019). Improving long‐term hydropower inflow forecasts by assimilating snow data.
• Pirk, Norbert; Ramtvedt, Eirik Næsset; Decker, Sven; Cassiani, Massimo; Burkhart, John & Stordal, Frode [Vis alle 7 forfattere av denne artikkelen] (2019). Causes of surface energy imbalances of eddy covariance measurements in mountainous terrain.
• Teweldebrhan, Aynom Tesfay; Burkhart, John & Schuler, Thomas (2018). Parameter uncertainty analysis for a distributed hydrological model.
• Filhol, Simon; Thomas, Schuler & Burkhart, John (2017). The Morphological evolution of a wind-shaped snow surface during a storm event at Finse, NO.
• Filhol, Simon; Pirk, Norbert; Schuler, Thomas & Burkhart, John (2017). The Evolution of a Snow Dune Field.
• Teweldebrhan, Aynom Tesfay; Burkhart, John & Schuler, Thomas (2017). Parameter identification for a Distributed hydrological model using the GLUE method.
• Teweldebrhan, Aynom Tesfay; Burkhart, John & Schuler, Thomas (2017). Parameterizing snow redistribution effect of topographic parameters in a conceptual hydrological model.
• Burkhart, John; Decker, Sven; Filhol, Simon; Hulth, John; Nesje, Atle & Schuler, Thomas [Vis alle 8 forfattere av denne artikkelen] (2017). Development of the Finse Alpine Research Station towards a platform for multi-disciplinary research on Land-Atmosphere Interaction in Cold Environments (LATICE).
• Tweldebrahn, Aynom Tesfay; Burkhart, John & Schuler, Thomas (2017). Parameterizing snow redistribution effect of topographic parameters in a conceptual hydrological model.
• Tweldebrahn, Aynom Tesfay; Burkhart, John & Schuler, Thomas (2017). Snow Distribution Modelling and Uncertainty Analysis using a Conceptual Hydrological Model.
• Filhol, Simon; Schuler, Thomas; Burkhart, John; Hulth, John & Decker, Sven (2017). A network of instrumentation to keep track of snow distribution at Finse, Norway.
• Filhol, Simon; Pirk, Norbert; Schuler, Thomas & Burkhart, John (2017). The morphological evolution of a wind-shaped snow surface during a storm event at Finse, Norway.
• Schuler, Thomas; Tweldebrahn, Aynom Tesfay; Filhol, Simon & Burkhart, John (2017). ESCYMO activities and linkage to SnowHow.
• Burkhart, John; Schuler, Thomas; Tallaksen, Lena M.; Filhol, Simon; Hulth, John & Decker, Sven (2016). Snow model validation in Norway at the Land Atmosphere Interaction in Cold Environments (LATICE) Finse site.
• Filhol, Simon; Burkhart, John; Schuler, Thomas & Hulth, John (2016). Capturing snow depth distribution with a low cost and wireless weather station network.
• Filhol, Simon; Burkhart, John; Schuler, Thomas & Hulth, John (2016). Weather stations for wind-blown snow at Finse, Norway: A distributed and real-time wireless network of.
• Filhol, Simon; Burkhart, John; Schuler, Thomas & Hulth, John (2016). A distributed and real-time wireless network of weather stations for wind-blown snow at Finse, Norway.
• Schuler, Thomas; Aalstad, Kristoffer; Aas, Kjetil Schanke; Burkhart, John; Dunse, Thorben & Filhol, Simon [Vis alle 9 forfattere av denne artikkelen] (2016). Towards real-time snow products for Svalbard.
• Mesquita, Michel d. S.; Jackson, Miriam; Nesje, Atle & Burkhart, John (2015). Summary of previous day activities and pending discussions.
• Mesquita, Michel d. S.; Jackson, Miriam; Nesje, Atle & Burkhart, John (2015). Welcome to the INDNOR Collaborative Workshop 2015.
• Jackson, Miriam; Mesquita, Michel d. S.; Nesje, Atle & Burkhart, John (2014). Introduction and remarks on the INDNOR Collaboration.
• Storvold, Rune; Solbø, Stian; Burkhart, John; Pedersen, Christina Alsvik & Gerland, Sebastian (2014). Attitude and Atmospheric Corrections of UAS Based Hyper Spectral Remote Sensing Reflectance Measurements.
• Orsolini, Yvan & Burkhart, John (2013). Nye forskningsrådsprosjekter: Norsk Klimaforskning til India. [Internett]. NILU.
• Storvold, Rune; Mulac, Brenda; Lesenkov, Sergey; Marshall, Douglas & Burkhart, John (2013). Use of Unmanned Aircraft for Scientific Data Collection in the Arctic. The Arctic Herald Information & Analytical Journal. ISSN 2304-3032. 1(5), s. 64–71.
• Solbø, Stian; Storvold, Rune & Burkhart, John (2011). Sea ice mapping using unmanned aerial systems.
• Teweldebrhan, Aynom Tesfay; Burkhart, John & Schuler, Thomas (2019). Ensemble-based uncertainty quantification and reduction in hydrological modelling and predictions. University of Oslo. ISSN 1501-7710.

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