Quantifying expert consensus against the existence of a secret, large-scale atmospheric spraying program
Nearly 17% of people in an international survey said they believed the existence of a secret large-scale atmospheric program (SLAP) to be true or partly true. SLAP is commonly referred to as ‘chemtrails’ or ‘covert geoengineering’, and has led to a number of websites purported to show evidence of widespread chemical spraying linked to negative impacts on human health and the environment.
To address these claims, we surveyed two groups of experts—atmospheric chemists with expertise in condensation trails and geochemists working on atmospheric deposition of dust and pollution—to scientifically evaluate for the first time the claims of SLAP theorists. Results show that 76 of the 77 scientists (98.7%) that took part in this study said they had not encountered evidence of a SLAP, and that the data cited as evidence could be explained through other factors, including well-understood physics and chemistry associated with aircraft contrails and atmospheric aerosols.
Our goal is not to sway those already convinced that there is a secret, large-scale spraying program—who often reject counter-evidence as further proof of their theories—but rather to establish a source of objective science that can inform public discourse.
published in Environmental Research Letters
Christine Shearer *†, Mick West §, Ken Caldeira ‡ and Steven J. Davis *†
* Near Zero
† University of California, Irvine, Department of Earth System Science
§ Metabunk.org
‡ Carnegie Institution for Science, Department of Global Ecology
Expert participants
78 experts participated in the elicitations for this report:
Andrew Carleton
Penn State University
Andrew Heidinger
National Oceanic and Atmospheric Administration
Andrew Heymsfield
National Center for Atmospheric Research (NCAR)
Andrew J. Weinheimer
National Center for Atmospheric Research
Anne-Catherine Pierson-Wickmann
University of Rennes 1
Brian A. Ridley
National Aeronautics and Space Administration
Bruce Anderson
National Aeronautics and Space Administration
Bryan Baum
University of Wisconsin-Madison
Carmen Nezat
Eastern Washington University
Carol Kendall
US Geological Survey
Charles A. Brock
National Oceanic and Atmospheric Administration
Charles E. Kolb
Aerodyne Research
Chris Measures
University of Hawaii
Christine Fichter
German Aerospace Center (DLR)
Christopher Hissler
Gabriel Lippmann Public Research Centre
Christos Zerefos
University of Athens
Clifton Buck
Franklin College
Cynthia Twohy
NorthWest Research Associates
Daniel Engstrom
University of Minnesota
Darrel Baumgardner
Droplet Measurement Technologies
David Doelling
National Aeronautics and Space Administration
David Grantz
University of California at Riverside
David J. Travis
University of Wisconsin-Whitewater
David Kratz
National Aeronautics and Space Administration
David Lee
Manchester Metropolitan University
David Lewellen
West Virginia University
Dominik Weiss
Imperial College London
Donald P. Garber
National Aeronautics and Space Administration
Eleftheratos Konstantinos
University of Athens
Gaby Radel
University of Reading
Guy Febvre
Observatory of Atmospheric Physics at Clermont-Ferrand
Hartmut Grassl
Max Planck Institute for Meteorology
Heleen de Wit
Norwegian Institute for Water Research
Jack Dibb
University of New Hampshire
Jan Kramers
University of Johannesburg
Jill Schrlau
Oregon State University
Joanna Clark
University of Reading
Josef Hejzlar
Institute of Hydrobiology
Karen Rosenlof
National Oceanic and Atmospheric Administration
Kiminori Shitashima
Kyushu University
Klaus Gierens
German Aerospace Center (DLR)
Larry Miloshevich
Milo Scientific
Lubos Boruvka
Czech University of Life Sciences Prague
Marjorie Schulz
US Geological Survey
Mark Smits
Hasselt University
Markus Garhammer
Ludwig-Maximilians-University
Matt Kulp
US National Park Service
Matthias Tesche
Stockholm University
Michael Ponater
German Aerospace Center (DLR)
Michael Prather
University of California at Irvine
Nicolas Belanger
University of Quebec
Otto Klemm
University of Muenster
Patrick Minnis
National Aeronautics & Space Administration
Pavel Rosendorf
T. G. Masaryk Water Research Institute
Piers Forster
University of Leeds
R. Paul Lawson
Stratton Park Engineering Company
Rabi Palikonda
National Aeronautics & Space Administration
Reinhold Busen
German Aerospace Center (DLR)
Robert Duce
Texas A&M University
Robert Sausen
Institute of Atmospheric Physics
Robert Talbot
University of Houston
Rolf David Vogt
University of Oslo
Ru-Shan Gao
National Oceanic and Atmospheric Administration
Scott Bailey
US Forest Service
Sonia M. Kreidenweis
Colorado State University
Stephan Bakan
Max Planck Institute for Meteorology
Steve Howell
University of Hawaii
Tatiana Khokhlova
University of Washington
Thilo Stilp
European Aviation Group for Occupational Safety and Health
Tomas Navratil
Czech Geological Survey
Tove Svenby
Norwegian Institute for Air Research
Ulrich Schumann
Institute of Atmospheric Physics
Ulrike Burkhardt
German Aerospace Center (DLR)
Volker Grewe
Institute of Atmospheric Physics
William L. Smith
National Aeronautics and Space Administration
William Landing
Florida State University
Wim de Vries
Wageningen University