A Study of Climate Change and Cost Effective Mitigation of the Baltic Sea Eutrophication

Description

Climate change and structural changes in the agricultural sector are considered to be the major drivers of future nutrient loads to the Baltic Sea. Climate change is expected to change the precipitation pattern in the drainage basin, leading to an increase in mean annual river-flows in the northen drainage basins of the Sea and a decrease in mean annual river-flows in the southern part of the catchment.

The purpose of the study is to calculate cost-effective solutions to the reduction of nutrient loads stipulated by the Baltic Sea Action Plan (BSAP) under four different scenarios of climate change. The effects of agricultural change and demographic changes were also taken into consideration to calculate  future nutrient loads. A numerical dynamic discrete model was aplied to calculate impacts on total abatement costs and associated allocation among the riparian countries.

The results indicate that impacts of climate change may facilitate the implementation of BSAP because of lower abatement costs. Abatement costs decrease with the severity of climate change, regardless of which climate change model is being used. When both agricultural and demographic changes in the climate change scenarios are included, an increase in abatement costs compared to the reference case was observed. In this scenario the major drivers of future nutrient loads to the Baltic Sea work in different directions: climate and demographic changes both lead to lower total abatement costs while agricultural change leads to an increase in abatement costs. Several limitations to the study have been put in evidence including uncertainty in the climate change analysis, variability of future nutrient outflow, unknown development in nutrient abatement technology and in marine ecosystem response to climate change.

 

Reference information