Work package 5: Ocean alkalinization biogeochemistry and ecosystem impacts

Leaders: University of Hamburg, GEOMAR Helmholtz Centre for Ocean Research Kiel
Partner: ULPGC

Prof. Jens Hartmann // University of Hamburg
Prof. Ulf Riebesell // GEOMAR

Prof. Javier Arístegui Ruiz // University of Las Palmas de Gran Canaria
Dr. María Montero // University of Las Palmas de Gran Canaria
Dr. Markus Schartau // GEOMAR
Dr. Jan Taucher // GEOMAR
Mathias Haunost // GEOMAR
Nicolas Smith Sanchez // GEOMAR
Niels Suitner // University of Hamburg

This work package will conduct a series of experiments at different scales and complexities to generate a robust data base on (1) the suitability of relevant minerals for ocean alkalinization purposes and (2) the ecological and biogeochemical impacts of ocean alkalinization approaches on natural pelagic ecosystems. While results of the former will provide recommendations on the most appropriate minerals and guide the in situ mesocosm experiments, the latter will provide a knowledge base to assess the effectiveness of different ocean alkalinization approaches as well as their possible ecological risks and side effects. This includes testing the green vs. white ocean hypothesis (dominance of diatoms vs. coccolithophores), with the latter representing a “CO2 leakage” term, reducing the efficiency of ocean alkalinization.


  1. To provide an assessment on the suitability of various minerals for ocean alkalinization purposes
  2. To examine ecological and biogeochemical responses to different approaches of ocean alkalinization in representative pelagic systems