Russell Bewick, OHB System AG, Universitätsallee 27–29, Bremen 28359, Germany. E-mail: rusbewick@hotmail.com

Taraka Davies-Barnard, School of Geographical Sciences, University of Bristol, University Road, Bristol BS8 1SS, United Kingdom. E-mail: t.davies-barnard@bristol.ac.uk

Stuart Haszeldine, Grant Institute, The King's Buildings, West Mains Road, Edinburgh EH9 3JW, United Kingdom, Email: s.haszeldine@ed.ac.uk

Klaus S. Lackner, Columbia University, Lenfest Center for Sustainable Energy and Department of Earth and Environmental Engineering, New York, NY 10027, USA. Email: kl2010@columbia.edu

Tim M. Lenton, College of Life and Environmental Sciences, University of Exeter, Level 7, Laver Building, Exeter EX4 4QE, United Kingdom. Email: t.m.lenton@exeter.ac.uk

Colin R. McInnes, Department of Mechanical and Aerospace Engineering, University of Strathclyde, Glasgow G1 1XJ, United Kingdom. E-mail: colin.mcinnes@strath.ac.uk

Richard Owen, Business School, University of Exeter, Rennes Drive, Exeter, EX4 4PU, United Kingdom. E-mail: r.j.owen@exeter.ac.uk

Francis D. Pope, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom. E-mail: f.pope@bham.ac.uk

Alan Robock, Department of Environmental Sciences, School of Environmental and Biological Sciences, Rutgers University, 14 College Farm Road, New Brunswick, New Jersey 08901-8551, USA. E-mail: robock@envsci.rutgers.edu

Stephen H. Salter, Institute for Energy Systems, School of Engineering, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JL, Scotland, United Kingdom. Email: S.Salter@ed.ac.uk

Joan Pau Sanchez, Department of Applied Mathematics, Universitat Politècnica de Catalunya, Calle Jordi Girona, Barcelona 08034, Spain. E-mail: jpau.sanchez@upc.edu

Vivian Scott, Grant Institute, The King's Buildings, West Mains Road, Edinburgh EH9 3JW, United Kingdom. E-mail: Vivian.scott@ed.ac.uk

Thomas Stevenson, Institute for Energy Systems, School of Engineering, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JL, Scotland, United Kingdom. Email: Tom.Stevenson@ee.ed.ac.uk

John Thornes, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom. E-mail: j.e.thornes@bham.ac.uk

Andreas Tsiamis, Scottish Microelectronics Centre, University of Edinburgh, West Mains Road, Edinburgh EH9 3JF, Scotland, United Kingdom. Email: A.Tsiamis@ed.ac.uk