The Weather Modification Association’s Response to the National Research Council’s Report Titled, “Critical Issues in Weather Modification Research”


  • Bruce Boe
  • George Bomar
  • William R Cotton
  • Byron L Marler
  • Harold D Orville
  • Joseph A Warburton


Last fall the National Research Council of the National Academy of Sciences published a report entitled, “Critical Issues in Weather Modification Research”. One of their conclusions was that “there is still no convincing scientific proof of the efficacy of international weather modification efforts. In some instances there are strong indications of induced changes, but this evidence has not been subject to tests of significance and reproducibility.” The report was very disappointing, with little support for operational cloud seeding. It showed little support for hail suppression and it was extremely short on its review of winter orographic cloud seeding. At the WMA semi-annual executive board meeting held in Reno, Nevada on October 17, 2003, there was a lively discussion about the report but little detail was known. It was concluded that the WMA needed to respond to the report and its conclusions. The board voted to charge Rick Stone, its president, with forming an ad-hoc committee to review the report and develop a statement reflecting the WMA position on the report. This was done in early November, with Bruce Boe, George Bomar, William Cotton, Byron Marler, Harold Orville and Joe Warburton being appointed as members. The committee solicited input from all members of the WMA before its meeting in early December in Fort Collins. The first draft was distributed to all members and further input invited. The committee received numerous comments and many additions and changes were made. The final report was completed in early February. A press release was issued in March. This WMA report is intended to provide an informed review to the membership and to the public and is now published on the WMA web page ( as well as being published in this current WMA Journal. In addition the report has been sent to various political leaders, policy makers, and scientists in the U.S. and abroad.

Author Biography

Harold D Orville





Technical Notes and Correspondence