Phenology is the study of periodically occurring developmental stages in the life cycles of plants and animals throughout the course of the year, and their relationship to weather patterns and climate. Examples include flowering, bud burst, insect emergence, bird nesting, fruit ripening, and leaf fall. These events are also referred to as phenological phases. The involvement of volunteer observers or citizen scientists forms the backbone of every phenological observation network — in Austria, over 300 volunteer observers regularly report data on currently 60 plant and 8 animal species. Phenology also captures changes in the seasonal behaviour of species in response to climate change and illustrates this in an easily accessible way.

The role that volunteer observers and citizen scientists play in the phenological observation network in Austria, and how phenology can be seen as a climate change indicator in Austria, is discussed by authors Helfried Scheifinger, Thomas Hübner, Hans Ressl, Markus Ungersböck and Gernot Zenkl from GeoSphere Austria in the newly published CCCA Fact Sheet!