Former Director, the Inter American Institute (IAI) for Global Change Research, São Paulo, Brazil. Professor on leave from Georg-August Universitat of Gottingen, Germany. Alexander von Humboldt Science Awardee (1998). Prof Tiessen is an agriculture science expert with deep knowledge of land use impacts on climate change; he received the IPPC's recognition for contributions to the 2007 Nobel Peace Prize. He has held visiting professorships in University of Bonn, Germany; Universidad Nacional de La Pampa, Argentina, Universidad Autonoma de Yucatan, México; Universidad Central de Venezuela, Caracas and Unversidade Federal de Pernambuco, Brazil. During 2005-2016 he led the Inter-American Institute for Global Change Research concentrating on science governance and management.