The goal of Baltic Earth (www.baltic.earth) is to achieve an improved Earth system understanding of the Baltic Sea region, encompassing processes in the atmosphere, on land, and in the sea, as well as processes and impacts related to the anthroposphere; i.e. the human impact is to be assessed at all levels wherever possible and reasonable. Recent research has shown that the observed environmental changes are often caused by a mixture of interwoven factors such as climate change and its associated impacts, eutrophication, pollution, fisheries, land cover change, and others. Each of these factors has a scientific and a societal dimension, which are often interdependent, and make the identification of a single or even dominant factor responsible for the change difficult.

The scope of this special issue is to attempt to describe the different factors for change, their impacts on the Earth system of the Baltic Sea region, and to demonstrate the capacity to model any of these factors in a single or a coupled approach. Are we able to simulate the observed changes in a realistic way? Are we able to produce credible scenarios for the future? Ultimately, this analysis should help to identify knowledge gaps and research needs for the coming years, to help find solutions for the challenges we face in the future.

The special issue refers to the 1st Baltic Earth Conference, held in Nida, Lithuania, 13–17 June 2016, which brought together the Baltic Earth research community to share and discuss issues related to the general conference topic "Multiple drivers for Earth System changes in the Baltic Sea region".