Search Results - "Koponen, Sampsa"

A novel method for detecting lake ice cover using optical satellite data by Heinilä, Kirsikka, Mattila, Olli-Pekka, Metsämäki, Sari, Väkevä, Sakari, Luojus, Kari, Schwaizer, Gabriele, Koponen, Sampsa

“…•The method uses gaussian mixture model (GMM) applied to optical data.•Unlike many other implementations, the method uses an integrated cloud classifier.•Even…”
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Testing the performance of empirical remote sensing algorithms in the Baltic Sea waters with modelled and in situ reflectance data by Ligi, Martin, Kutser, Tiit, Kallio, Kari, Attila, Jenni, Koponen, Sampsa, Paavel, Birgot, Soomets, Tuuli, Reinart, Anu

“…Remote sensing studies published up to now show that the performance of empirical (band-ratio type) algorithms in different parts of the Baltic Sea is highly…”
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Application of an empirical neural network to surface water quality estimation in the Gulf of Finland using combined optical data and microwave data by Zhang, Yuanzhi, Pulliainen, Jouni, Koponen, Sampsa, Hallikainen, Martti

“…Since neural networks have been widely applied to the nonlinear transfer function approximation, we present an empirical neural network algorithm to estimate…”
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Water quality retrievals from combined Landsat TM data and ERS-2 SAR data in the Gulf of Finland by Yuanzhi Zhang, Pulliainen, J.T., Koponen, S.S., Hallikainen, M.T.

“…This paper presents the applicability of combined Landsat Thematic Mapper and European Remote Sensing 2 synthetic aperture radar (SAR) data to turbidity,…”
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Detection of water quality using simulated satellite data and semi-empirical algorithms in Finland by Härmä, Pekka, Vepsäläinen, Jenni, Hannonen, Tuula, Pyhälahti, Timo, Kämäri, Juha, Kallio, Kari, Eloheimo, Karri, Koponen, Sampsa

“…The aim of the study was to test the feasibility of the band combination of the TERRA MODIS and ENVISAT MERIS instruments for operational monitoring of lakes…”
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A semi-operative approach to lake water quality retrieval from remote sensing data by Pulliainen, Jouni, Kallio, Kari, Eloheimo, Karri, Koponen, Sampsa, Servomaa, Henri, Hannonen, Tuula, Tauriainen, Simo, Hallikainen, Martti

“…A semi-operative approach to retrieve chlorophyll-a concentration from airborne/spaceborne spectrometer observations has been developed and tested using the…”
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Temporal patterns of phytoplankton phenology across high latitude lakes unveiled by long-term time series of satellite data by Maeda, Eduardo Eiji, Lisboa, Filipe, Kaikkonen, Laura, Kallio, Kari, Koponen, Sampsa, Brotas, Vanda, Kuikka, Sakari

“…Monitoring temporal changes in phytoplankton dynamics in high latitude lakes is particularly timely for understanding the impacts of warming on aquatic…”
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Satellite bathymetry estimation in the optically complex northern Baltic Sea by Kulha, Niko, Ruha, Leena, Väkevä, Sakari, Koponen, Sampsa, Viitasalo, Markku, Virtanen, Elina A.

“…Satellite bathymetry estimation (SBE) is a cost-effective method for producing depth information for shallow marine and aquatic areas. However, most SBE…”
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Machine Learning Regression Approaches for Colored Dissolved Organic Matter (CDOM) Retrieval with S2-MSI and S3-OLCI Simulated Data by Ruescas, Ana Belen, Hieronymi, Martin, Mateo-Garcia, Gonzalo, Koponen, Sampsa, Kallio, Kari, Camps-Valls, Gustau

“…The colored dissolved organic matter (CDOM) variable is the standard measure of humic substance in waters optics. CDOM is optically characterized by its…”
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Applicability of Earth Observation chlorophyll-a data in assessment of water status via MERIS — With implications for the use of OLCI sensors by Attila, Jenni, Kauppila, Pirkko, Kallio, Kari Y., Alasalmi, Hanna, Keto, Vesa, Bruun, Eeva, Koponen, Sampsa

“…Earth Observation (EO) offers spatially and temporally unique data for generating information required under various environmental regulations for assessing…”
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MERIS Case II water processor comparison on coastal sites of the northern Baltic Sea by Attila, Jenni, Koponen, Sampsa, Kallio, Kari, Lindfors, Antti, Kaitala, Seppo, Ylöstalo, Pasi

“…Three MERIS Case II water processors included in the BEAM software package were studied for estimating the water quality in the coastal waters of the northern…”
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Application of empirical neural networks to chlorophyll-a estimation in coastal waters using remote optosensors by Yuanzhi Zhang, Koponen, S.S., Pulliainen, J.T., Hallikainen, M.T.

“…This paper presents chlorophyll-a estimation in coastal waters off the Gulf of Finland using remote optosensors. Concurrent remote optosensor data and in situ…”
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The accuracy of snow melt-off day derived from optical and microwave radiometer data — A study for Europe by Metsämäki, Sari, Böttcher, Kristin, Pulliainen, Jouni, Luojus, Kari, Cohen, Juval, Takala, Matias, Mattila, Olli-Pekka, Schwaizer, Gabriele, Derksen, Chris, Koponen, Sampsa

“…This paper describes the methodology for deriving yearly pixel-wise snow melt-off day maps from optical data-based FSC (Fractional Snow Cover) without…”
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Optical model for the Baltic Sea with an explicit CDOM state variable: a case study with Model ERGOM (version 1.2) by Neumann, Thomas, Koponen, Sampsa, Attila, Jenni, Brockmann, Carsten, Kallio, Kari, Kervinen, Mikko, Mazeran, Constant, Müller, Dagmar, Philipson, Petra, Thulin, Susanne, Väkevä, Sakari, Ylöstalo, Pasi

“…Colored dissolved organic matter (CDOM) in marine environments impacts primary production due to its absorption effect on the photosynthetically active…”
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Assimilation of satellite data to 3D hydrodynamic model of Lake Säkylän Pyhäjärvi by Mano, Akiko, Malve, Olli, Koponen, Sampsa, Kallio, Kari, Taskinen, Antti, Ropponen, Janne, Juntunen, Janne, Liukko, Ninni

“…To analyze the applicability of direct insertion of total suspended matter (TSM) concentration field based on turbidity derived from satellite data to…”
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Lake water quality classification with airborne hyperspectral spectrometer and simulated MERIS data by Koponen, Sampsa, Pulliainen, Jouni, Kallio, Kari, Hallikainen, Martti

“…We study the use of airborne and simulated satellite remote sensing data for classification of three water quality variables: Secchi depth, turbidity, and…”
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Assimilation of satellite data to 3D hydrodynamic model of Lake Saekylaen Pyhaejaervi by Mano, Akiko, Malve, Olli, Koponen, Sampsa, Kallio, Kari, Taskinen, Antti, Ropponen, Janne, Juntunen, Janne, Liukko, Ninni

“…To analyze the applicability of direct insertion of total suspended matter (TSM) concentration field based on turbidity derived from satellite data to…”
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Landsat ETM+ Images in the Estimation of Seasonal Lake Water Quality in Boreal River Basins by Kallio, Kari, Attila, Jenni, Härmä, Pekka, Koponen, Sampsa, Pulliainen, Jouni, Hyytiäinen, Ulla-Maija, Pyhälahti, Timo

“…We investigated the use of Landsat ETM+ images in the monitoring of turbidity, colored dissolved organic matter (CDOM), and Secchi disk transparency (ZSD) in…”
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A case study of airborne and satellite remote sensing of a spring bloom event in the Gulf of Finland by Koponen, Sampsa, Attila, Jenni, Pulliainen, Jouni, Kallio, Kari, Pyhälahti, Timo, Lindfors, Antti, Rasmus, Kai, Hallikainen, Martti

“…The concentrations of chlorophyll- a (chl- a), total suspended solids (TSS) and the absorption coefficient of colored dissolved organic matter ( a CDOM(400))…”
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Proxy Indicators for Mapping the End of the Vegetation Active Period in Boreal Forests Inferred from Satellite-Observed Soil Freeze and ERA-Interim Reanalysis Air Temperature by Böttcher, Kristin, Rautiainen, Kimmo, Aurela, Mika, Kolari, Pasi, Mäkelä, Annikki, Arslan, Ali N., Black, T. Andrew, Koponen, Sampsa

“…Triggered by decreases in photoperiod and temperature, evergreen needle-leaved trees in the boreal region downregulate photosynthetic activity and enter…”
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