Nirlungayuk, Gabriel: Deputy Minister of the Environment, Nunavut
Norman, David: Director of Campaigns, WWF-UK
Nurse, Sir Paul: Geneticist and President of the Royal Society
Obama, Barack: President of the United States
O'Keefe, William: CEO, George C. Marshall Institute
Oreskes, Naomi: Science historian and co-author of Merchants of Doubt
Otto, Dr. Friederike: Deputy Director, Environmental Change Institute
Pachauri, Dr Rajendra: Chairman of the IPCC
Paddock, William C.: Consultant and co-author of Famine 1975!
Palmer, Professor Tim: Director, Programme on Modelling and Predicting Climate, Oxford University
Parr, Dr. Doug: Chief Scientist and Policy Director, Greenpeace UK
Pearce, Fred: Science writer and journalist
Peiser, Dr. Benny: Director, Global Warming Policy Foundation
Pendleton, Andrew: Head of Campaigns, Friends of the Earth
Perry, Charles: Co-founder, SecondNature and former Director, BP Green Energy
Pershing, Jonathan: Former US Deputy Special Envoy for Climate Change
Pethica, Professor John: Professor of material science and Fellow of the Royal Society
Pidgeon, Professor Nick: Professor of Environmental Psychology, Cardiff University
Pinker, Steven: Professor of Psychology, Harvard University
Pope, Dr. Vicky: Head of Integration and Growth, UK Met Office Hadley Centre
Porter, David: Chief Executive of the Association of Electricity Producers (UK)
Porritt, Jonathon: Environmentalist and writer
Prescott, John: Former UK Deputy Prime Minister, Council of Europe's rapporteur on climate change
Rapley, Professor Chris: Director of the British Antarctic Survey, 1998-2007
Read, Rupert: Academic and Green Party (UK) politician
Reitze, Dr. Arnold: Professor of Environmental Law, George Washington University Law School
Ridley, Matt: Author of The Rational Optimist
Robinson, Mary: Former UN High Commissioner for Human Rights
Rockström, Professor Johan: Executive Director, Stockholm Resilience Centre
Rowlatt, Justin: BBC presenter and "Ethical Man"
Rudd, Amber: Secretary of State for Energy and Climate Change in the UK
Rusbridger, Alan: Editor-in-chief, The Guardian
Rutter, Jill: Programme director, Institute for Government
Sagan, Professor Carl: Astronomer, astrophysicist and author
Saño, Naderev "Yeb": The Philippines' delegate to the COP19 climate summit in Warsaw
Sarmad, Ovais: Deputy Executive Secretary, UNFCCC
Sauven, John: Executive Director, Greenpeace UK
Scaife, Dr Adam: Meteorologist, Met Office Hadley Centre
Schmidt, Dr. Gavin: Director, NASA Goddard Institute for Space Studies
Schneider, Professor Stephen: Professor of Environmental Biology and Global Change at Stanford University
Sen, Amartya: Philosopher and economist
Shaw, Nicola: Chief Executive of the UK National Grid
Shine, Professor Keith: Regius Professor of Meteorology and Climate Science, Reading University
Shuckborough, Dr. Emily: Head of Open Oceans, British Antarctic Survey
Silver, Nate: Author and statistician
Simms, Andrew: Fellow of the New Economics Foundation
Singer, Professor Fred: Emeritus professor of environmental science at University of Virginia
Skinner, Dr Luke: Palaeoclimatologist, Department of Earth Sciences, Cambridge University
Slingo, Professor Julia: Chief Scientist, UK Met Office
Smith, Lord: Chris Smith, Former Chairman of the Environment Agency, UK
Sparks, Professor Tim: Nature advisor to the Woodland Trust
Spencer, Dr Roy: Climatologist and a Principal Research Scientist for the University of Alabama in Huntsville
Stark, Chris: CEO, Committee on Climate Change
Steiner, Achim: Executive Director, UNEP
Stern, Lord Nicholas: Baron Stern of Brentford, British economist and academic
Stevens, Fisher: Director and producer of Before the Flood
Stewart, Duncan: Environmentalist, architect, former presenter of RTE programme Eco Eye
Stewart, Professor Iain: Geologist and Professor of Geoscience Communication at the University of Plymouth
St Louis, Connie: Lecturer in science journalism, City University
Stocker, Professor Thomas: Co-Chair, IPCC Working Group I
Stordalen, Dr. Gunhild A.: Co-founder and President of EAT Foundation
Stott, Dr. Peter: Leader of Climate Monitoring and Attribution Team, UK Met Office
Stott, Professor Philip: Professor emeritus of biogeography at SOAS, University of London
Stringer, Graham: Labour MP, UK Parliament
Sulston, Sir John: Biologist, Chair of the Institute for Science, Ethics and Innovation (iSEI) at the University of Manchester
Sutton, Professor Mark:Environmental physicist, Centre for Ecology and Hydrology
Sutton, Professor Rowan: Director of NCAS, researcher at Walker Institute
Suzuki, David: Canadian academic and environmental activist
Swinburn, Professor Boyd: Professor of Population Nutrition and Global Health, University of Auckland
Swingland, Professor Ian: Conservation biologist
Taalas, Petteri: Secretary-General, World Meteorological Organization
Taylor, Dr. Mitchell: Polar bear expert, Lakehead University
Thatcher, Margaret: Prime Minister of Great Britain, 1981 - 1990
Thomas, Professor Stephen: Professor of Energy Studies, Greenwich University
Thompson, Emma: Hollywood actress and climate campaigner
Thunberg, Greta: Climate change activist
Tindale, Stephen: Associate fellow, Centre for European Reform, also former Executive Director, Greenpeace UK
Tittensor, Dr Derek: Research scientist working on issues of marine biodiversity
Townsend, Solitaire: Co-founder and Chief Executive of Futerra Sustainability Communications
Tol, Professor Richard: Professor of Economics, University of Sussex
Trenberth, Dr Kevin: Head of Climate Analysis, National Centre for Atmospheric Research
Tschakert, Professor Petra: Assistant Professor of Geography, Pennsylvania State University
Turner, Lord Adair: Chairman, Committee on Climate Change (UK government advisory body)
Turner, Professor John: Leader of Climate Variability and Modelling group, British Antarctic Survey
Turney, Professor Chris: Professor of Climate Change, UNSW
Tutu, Desmond: Archbishop Emeritus of Cape Town and social activist
van der Linden, Dr. Sander: Social psychologist, Princeton University
Verdier, Philippe: Meteorologist and author
Vidal, John: Environment Editor, The Guardian
Vince, Dale: Owner of green UK electricity company Ecotricity
Vishvapani: Member of the Triratna Buddhist order
Wadhams, Professor Peter: Professor of Ocean Physics, University of Cambridge
Walley, Joan: Labour MP, UK Parliament, also Chair, House of Commons Environmental Audit Select Committee
Walport, Sir Mark: UK Government Chief Scientific Advisor
Ward, Bob: Policy and Communications Director, Grantham Research Institute on Climate Change
Watson, Professor Andrew: Climate scientist, School of Environmental Sciences, UEA
Watson, Professor Bob: Chief scientific advisor to UK Government's Department for the Environment
Watson, Professor Jim: Professor of Energy Policy, Director of the Sussex Energy Group
Watts, Anthony: Meteorologist, blogger and president, IntelliWeather Inc.
Weaver, Dr. Andrew: Climate scientist and politician
Weintrobe, Sally: Psychoanalyst
Westwood, Vivienne: English fashion designer and businesswoman, co-founder of Climate Revolution
Wheeler, Dr. Dennis: Reader in Geography, University of Sunderland
Whitehouse, Dr David: Astronomer, science editor at GWPF
Williams, Dr. Paul: Meteorologist and Royal Society Research Fellow, University of Reading
Willis, Professor Rebecca: Professor in Practice, Lancaster University
Windsor, Prince Charles: HRH The Prince of Wales
Worthington, Baroness Bryony: British environmental campaigner and Labour life peer in the House of Lords
Wright, Martin: Chairman, Renewable Energy Alliance
Yeo, Tim: Conservative MP, Chairman of the Energy and Climate Change Select Committee (UK)
Zelnio, Kevin: Marine Biologist