Dataset containing images of algal blooms in the Baltic Sea. The data is provided with a metadata description containing time spotted, comments, municipality, county and coordinates of each image. The images and metadata file are archived in a zip package. Images show various summer surface accumulations of so-called harmful algal blooms (HABs) or nuisance blooms. Typically, these blooms consists of species of cyanobacteria of the order of Nostocales, including toxic Nodularia and Aphanizomenon. These blooms were verified by Informationscentralen (Länstyrelsen Stockholm and Länstyrelsen Västerbotten). However, the blooms seen in the images have not been taxonomically annotated by microscopy nor genetic analysis. The following data fields are contained in the metadata files (provided in both json and csv format): report_id: unique identifier for reporting record, type: string time_spotted: date that bloom was spotted, type: datetime algae_overview_photo: url to overview photo submitted, type: string algae_detail_photo: url to detailed photo submitted, type: string comments: Any additional information relating to the bloom, type: string lat: Latitude of position where bloom was seen, type: float long: Longitude of position where bloom was seen, type: float place: County where bloom was spotted, type: string kommun: Municipality where bloom was spotted, type: string Total observations: 251 Note: Not every observation has an accompanying image and others were verified using other information provided.

Part of subproject "Algal Blooms Sweden" within Ocean Data Factory Sweden. See Facebook page (https://www.facebook.com/algalbloomssweden/) and project website (https://oceandatafactory.se/) for more information.