2000年初,美国空军发布了一份未注明日期的情况说明书,表示阴谋论是一场恶作剧,部分源自于美国空军大学于1996年起草的战略文件《作为力量倍增器的天气:2025年呼风唤雨》(Weather as a Force Multiplier: Owning the Weather in 2025)[16][17]。这份文件是为了响应到2025年维持美国军事影响力,概述日后建立策略性天气改造(英语:Weather modification)系统的军事指令而提出的,是“未来情况或情景的虚构展示”[17]。2005年,空军进一步澄清,该文件“不反映目前的军事策略、实践或能力”,“未来没有开展任何天气改造系统试验或计划的计划[5][18]。”此外,空军表示化学尾迹恶作剧持续遭受调查,并受到众多权威高校、科研组织或主流媒体的驳斥[5]。
2001年,美国国会议员丹尼斯·库辛尼奇为回应选民诉求,拟定(但没有签署)法案编号H. R. 2977(第107届)2001年太空保护法案(Space Preservation Act of 2001),永远禁止在太空中使用武器,将化学尾迹列为将被禁止的“异国武器”[35][36][37]。支持者将这一对化学尾迹的明确提及,解读成政府承认其存在[20][38]。怀疑论者指出,质询中的法案提到“外形武器”和“环境、气候或构造武器”。法案受到美国国防部的不利评价,最终死在委员会手上,之后库辛尼奇三次尝试制定太空保护法案未果[39],文本均没有提及化学尾迹。
^ 2.002.012.022.032.042.052.062.072.082.09Watson, Traci. Conspiracy theorists read between lines in the sky. USA Today. 2001-03-07: A.04 [2018-04-03]. (原始内容存档于2012-12-17). Exasperated by persistent questions, the Environmental Protection Agency, NASA, the Federal Aviation Administration and the National Oceanic and Atmospheric Administration joined forces last fall to publish a fact sheet explaining the science of contrail formation. A few months earlier, the Air Force had put out its own fact sheet, which tries to refute its opponents' arguments point by point. "If you try to pin these people down and refute things, it's, 'Well, you're just part of the conspiracy,' " says atmospheric scientist Patrick Minnis of NASA's Langley Research Center in Hampton, Va. "Logic is not exactly a real selling point for most of them."
^ 3.03.1James, Nigel. Knight, Peter , 编. Contrails. Conspiracy Theories in American History: An Encyclopedia (ABC-CLIO). 2003: 197–199 [2018-04-22]. ISBN 978-1-57607-812-9. (原始内容存档于2021-02-06). there are no books on the subject to date. Reports on contrails are carried by dedicated websites...Mainstream news agencies rarely report on concerns over contrails, and when they do it is in terms of anti-government “paranoia.” When USA Today ran a contrail story it likened the story to something out of The X-Files, arguing that it was only those who are suspicious of the government who believe that lines in the sky are evidence of malfeasance.Some suggested that they are trying to slow down global warming with compounds that reflect sun-light into the sky.
^Cama, Timothy. EPA confronts ‘chemtrails’ conspiracy talk. the Hill. 2015-03-13 [2016-12-10]. (原始内容存档于2016-10-24). Conspiracy theorists say that government officials or others are using jets to spray harmful chemicals into the atmosphere. They cite the contrails left by jets as evidence of the chemicals. The EPA has added a new notice to its website, which links to a fact sheet explaining that the trails left by jets in the atmosphere are only ice particles and contain no harmful chemicals. “Contrails are line-shaped clouds or ‘Condensation trails’ composed of ice particles that are visible behind jet aircraft engines under certain atmospheric conditions and at times can persist,” says the notice, posted to the EPA’s website Friday. “EPA is not aware of any deliberate actions to release chemical or biological agents into the atmosphere.” Theorists have posited that the chemicals are meant to control the climate, to harm humans or to kill them. The fact sheet from the EPA and other federal agencies like the Federal Aviation Administration and the National Oceanic and Atmospheric Administration was first published in 2000, when the chemtrails conspiracy became popular on the Web. An EPA spokeswoman said the agency frequently receives questions about chemtrails.
^ 9.09.19.2Smith, Oliver. 'Chemtrails' and other aviation conspiracy theories. telegraph.co.uk. the Telegraph. 2013-09-24 [2016-12-11]. (原始内容存档于2016-12-22). So persistent is the chemtrail theory that US government agencies regularly receive calls from irate citizens demanding an explanation...The conspiracy theory took root in the Nineties, with the publication of a US Air Force research paper about weather modification...Governments and scientific institutions have of course dismissed the theories, and claim those vapour trails which persist for longer than usual, or disperse to cover a wide area, are just normal contrails.
^chemtrail. Oxford English Dictionary Third. Oxford University Press. December 2011 [2018-04-22]. (原始内容存档于2015-09-24).
^ 11.011.111.2Paul Simons. Weather Eye: contrail conspiracy. The Times. 2013-09-27 [2018-04-03]. (原始内容存档于2015-03-15). This conspiracy idea took hold in 1996 when the US Government was accused of trying to modify the weather for military means
^37th Parliament, 2nd Sessions Edited Hansard; Number 110 Contents. Publications: Debates: Committees of the House: Petitions: The Environment 1030. Parliament of Canada. 2003-06-03 [2009-04-13]. (原始内容存档于2010-11-18). Mr. John Herron (Fundy—Royal, PC): Mr. Speaker, I am presenting a petition on behalf of Mr. Brian Holmes of Ontario regarding aerial spraying. Mr. Holmes has collected signatures from across the country from concerned Canadians who believe that chemicals used in aerial sprayings are adversely affecting the health of Canadians. The petitioners call upon Parliament to stop this type of high altitude spraying. The petition has been duly certified by the clerk and I present it at this time.
^House of Commons Hansard - 8 November 2005: Column 314W-315W. United Kingdom Parliament. 2005-11-08 [2009-03-12]. (原始内容存档于2009-06-15). Mr. Morley: The Department is not researching into chemtrails from aircraft as they are not scientifically recognised phenomena.
"Lake Oroville Runoff Enhancement Project" Final Report (页面存档备份,存于互联网档案馆) submitted to California Dept. of Water Resources Division of Operations and Maintenance (September 1995); published by US Department of the Interior's Bureau of Reclamation Technical Service Center, River Systems and Meteorology Group.
Abstract: "Bureau of Reclamation cooperated with California Department of Water Resources to design and implement a snowpack augmentation program to increase runoff to Oroville Reservoir. The program involves collection of data to document physical processes leading to increased precipitation. This report summarizes main results from 3 yr of in-situ physical studies and statistical analysis of precipitation data collected during 87 randomized seeding cases. Liquid propane released from high elevation sites has proven to be a viable, reliable method of seeding wintertime clouds in the Sierra Nevada."