A data set of phenological observations of plants, birds, as well as agrarian activities and abiotic phenomena from Latvia, 1970-2018 is presented. The data include limited number of observations of insects, amphibians, mammals, mushrooms, mollusks and fishes as well. The data was collected by voluntary observers (citizen scientists) and published as paper based yearly bulletins. It includes almost 48 000 individual observations of 159 different phenological phases from 103 locations in Latvia. Each entry is comprised of following fields: Station: name of the observation station Year: year of observation Season: season of observation as indicated in the primary publication Species: English name of the species observed or description of phenomena observed in case of abiotic occurrences Species Latin: Latine name of the species observed Taxonomic_group: taxonomic group of the species observed or grouping of non-biological phases (“Abiotic” for meteorological phenomena and “Agrarian” for agrarian activities) Phenophase: description of phenological phase observed BBCH: attributed BBCH code for phenological phase observed, where applicable Date: date of the first observation of the phase DoY: day of the year of the first observation of the phase Implausible: flag indicating of the reported date of phenological phase is highly implausible (TRUE) or realistic (FALSE) Wrong_order: flag indicating if the order of the reported phases at a given station and year is not realistic (TRUE) or realistic (FALSE)

{"references": ["Kalv\u0101ne G., Kalv\u0101ns A., \u0122\u0113rmanis A., Long term phenological data set of multi-taxonomic groups and agrarian activities, abiotical parameters from Northern Europa, Latvia. Earth System Science Data (ESSD)"]}

The study was carried out within the framework of the ERDF project "Impact of Climate Change on Phytophenological Phases and Related Risks in the Baltic Region" (1.1.1.2/VIAA/2/18/265).