This study provides the first comprehensive research of wind-induced coastal upwelling in the South-Eastern (SE) Baltic Sea based on the analysis of satellite and conventional monitoring data over a period of 2000–2015. The analysis of multispectral satellite data enabled the analysis of both physical and biological properties of the coastal upwelling in a broad range of spatial and temporal scales. The detailed statistical information on upwelling properties in this region and the impact of the upwelling-induced inflows on the hydrological conditions of the Curonian Lagoon together with an insight of its possible impact on the marine environment of this region is provided. Additionally, for the first time an Ekman-based upwelling index (UI) is used over the study region to better understand the upwelling response to the background meteorological conditions, and to assess the effectiveness of satellite data in the upwelling studies over the SE Baltic Sea. The study results indicate that the upwelling-induced SST drop and its spatial properties are larger than were previously registered with the SST drop up to 14 ˚C and the total affected area up to 16000 km2 during extreme upwelling events. The analysis of satellite optical data shows a clear upwelling-induced decline in chlorophyll-a (Chla) concentration in the coastal zone and in the shallow Curonian Lagoon. It was also demonstrated that coastal upwellings might significantly influence water salinity and air temperature. The study outcomes suggest that satellite data is an effective tool for coastal upwelling detection in the Baltic Sea under relatively cloud-free summer conditions enabling the analysis of the coastal upwelling intensity, its biological and atmospheric response and, moreover, yielding significant information about the sea-lagoon interaction. This thesis also demonstrates the benefits of integrating multi-spectral satellite data for the monitoring of the Baltic Sea and the Curonian Lagoon environment.