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 Dr. Roy presents at NASA and Global Land Project meetings in Berlin, Germany
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Dr. Valeriy Kovalskyy
Postdoctoral Fellow

PhD (2011),
Geographic Science and Engineering, South Dakota State University, Brookings, South Dakota, Thesis title: Development and validation of the Event Driven Phenology Model
MSc (2004), Environmental Sciences, Ohio University, Athens, Ohio, USA.
BA (2001), Geography, Ivan Franko Lviv National University, Ukraine.
Current Position
Post-doctoral Research Associate, GIScCE, South Dakota State University, SD, senior WELD algorithm research, developer and programmer.

Hansen, M.C., Egorov, A., Potapov, P., Stehman, S.V., Tyukavina, A., Turubanova, S.A., Roy, D.P., Goetz, S.G., Loveland, T.R., Ju, J., Kommareddy, A., Kovalskyy, V., Forsythe, C., Bents, T., (2013). Monitoring CONUS land cover change with Web-Enabled Landsat Data (WELD), Remote sensing of Environment, In Press.

Roy, D.P., Qin, Y., Kovalskyy, V. , Vermote, E.F., Ju, J., Egorov, A., Hansen, M.C., Kommareddy, I., Yan, L., 2012. Conterminous United Stated states demonstration and characterization of MODIS-based Landsat ETM+ atmospheric correction. Remote Sensing of Environment, In Press.
Kovalskyy, V, Henebry, G.M., Roy, D.P., Adusei, B., Hansen, M., Senay, G., Mocko, D.M. 2012. Evaluation of a coupled event driven phenology and evapotranspiration model for croplands in the United States northern Great Plains. Journal of Geophysical Research – Atmospheres,118, 11, 5065-5081, doi: 10.1002/jgrd.50387.
Kovalskyy, V. and Roy D. P., 2013, The global availability of Landsat 5 TM and Landsat 7 ETM+ data land surface observations and implications for global 30m Landsat data product generation. Remote Sensing of Environment, 130, 280–293., (

Ju, J., Roy, D.P., Vermote, E., Masek, J., Kovalskyy, V., 2012, Continental-scale validation of MODIS-based and LEDAPS Landsat ETM+ atmospheric correction methods. Remote Sensing of Environment, 122, 175–184.
Kovalskyy, V. and Henebry, G. M., 2012, A new concept for simulation of vegetated land surface dynamics – Part 1: The event driven phenology model, Biogeosciences, 9, 141-159, doi:10.5194/bg-9-141-2012.
Kovalskyy, V. and Henebry, G. M., 2012, Alternative methods to predict actual evapotranspiration illustrate the importance of accounting for phenology – Part 2: The event driven phenology model, Biogeosciences, 9, 161-177, doi:10.5194/bg-9-161-2012.
Kovalskyy, V., Roy, D. P, Zhang, X. Y., Ju, J., 2011, The suitability of multi-temporalWeb-Enabled Landsat Data (WELD) NDVI for phenological monitoring – a comparison with flux tower and MODIS NDVI, Remote Sens. Lett., 3:4, 325–334.
Roy, D. P., Ju, J., Kline, K., Scaramuzza, P. L., Kovalskyy, V., Hansen, M., Loveland, T. R., Vermote, E., and Zhang, C.: Web-enabled Landsat Data (WELD): Landsat ETM+ composited mosaics of the conterminous United States, 2010, Remote Sensing of Environment, 114, 35-49, 10.1016/j.rse.2009.08.011.
Kovalskyy, V., and Henebry, G. M., 2009, Recent trends in land surface phenologies within the Don and Dnieper River basins from the perspective of MODIS collection 4 products, in: Regional Aspects of Climate-Terrestrial-Hydrologic Interactions in Non-boreal Eastern Europe, NATO Science for Peace and Security Series, Springer Netherlands, 183-189.
Kovalskyy, V., and Henebry, G. M., 2009, Change and persistence in land surface phenologies of the Don and Dnieper river basins, Environ. Res. Lett., 4, 045018, doi:10.1088/1748-9326/4/4/045018.