Chemtrails Conspiracy Theory

We receive many emails and letters asking me about chemtrails. Many express deep concern, some are abusive and threatening. This page gives our views on the topic.


Chemtrails refers to the theory that governments or other parties are engaged in a secret program to add toxic chemicals to the atmosphere from aircraft in a way that forms visible plumes in the sky, somewhat similar to contrails. Various different motivations for this alleged spraying are speculated, including sterilization, reduction of life expectancy, mind control or weather control.

We have not seen any credible evidence that chemtrails exist. If we did see any evidence that governments were endangering their own citizens in the manner alleged in the chemtrails conspiracy, we would be eager to expose and stop any such activities.

Our Research on Albedo Modification

We work on theoretical proposals for combating global warming called solar geoengineering or albedo modification. These are technologies that might enable people to add materials to the Earth's atmosphere to reflect a bit more sunlight back to space, partially masking or reducing the climate change due to accumulated greenhouse gases.

Study of solar geoengineering is in the very early stages and the topic is (rightly) a very controversial area of climate policy because if it ever were tested at large scales or implemented it could involve physical risks and would raise a range of serious socio-political and ethical issues. However, there is nothing secret about the study of albedo modification, with hundreds of publications about the topic in academic journals and hundreds of articles in mainstream media. You can find some of our work here.

We are confident that there is no currently active program to actually test or implement albedo modification outdoors.

We are not now involved in outdoor experimentation, though we are indeed actively developing proposals for field experiments. This experiment will proceed only if it is conducted in a fully transparent and public manner, and only if it passes a comprehensive independent safety review. The experimental plans, operations and results will be publicly available and freely usable (no patenting).

The Chemtrails Conspiracy Theory

Because of the apparent similarities between the proposed implementation methods for albedo modification (such as injecting reflective particles into the stratosphere), and the alleged methods for producing chemtrails, some people have linked the notion of chemtrails to the study of albedo modification.

There is No Evidence for the Existence of Chemtrails

Extraordinary claims require extraordinary proof. The claim that there is a large-scale secret program to spray materials from aircraft is extraordinary. Yet all the evidence we have seen to date has been very weak. The most common claim is simply that aircraft contrails look “different”, without any comparative analysis. This as convincing as saying that alien beings walk among in disguise as people because some people act very strangely.

If there really were a large-scale program dumping material from aircraft at the scale described, there would have to be a large operating program to manufacture, load and disperse materials. If such a program existed at the scale required to explain the claimed amount of chemtrails, it would require thousands or perhaps tens of thousands of people. It would be extraordinarily hard to keep such a program secret because it would be so easy for a single individual in the program to reveal it using leaked documents, photographs or actual hardware.

Moreover, if such a program was intended to cause harm to their fellow citizens—as is alleged by people who believe in the chemtrails conspiracy—then people working in the program would have very strong personal motivations to reveal it.

We don’t trust that governments will always do the right thing, but we do trust the goodwill of individual who take risks to blow the whistle, exposing government misdeeds.

Comments for People who Believe in Chemtrails

If you believe in chemtrails, ask yourself how you can be so certain that there is indeed a grand conspiracy. Consider alternative, simple explanations. Remember that the Internet is filled with people who are completely sure about stuff that just isn’t true. Remember that while governments can keep secrets that involve only a few people they do a very bad job of keeping large-scale programs secret. The Russians, for example, knew specific details about the Manhattan project before the first nuclear weapons test, and that was a case where those involved had a clear patriotic motivation to keep the secret.

If you think that aircraft contrails “look different” or are “behaving strangely” consider that regular aircraft condensation trails (contrails) are sometimes long-lasting and the way they look can change suddenly along a flight path as aircraft fly through regions with different temperature and humidity. This is well understood and has been demonstrated by ground observation and by scientific research performed by thousands of people over many decades. Of course it's possible that something else is going on, but to prove it one would need more than simple photographs of something that looks entirely consistent with normal contrails.

Finally here are some additional resources that may be of interest:

Several people who were concerned about chemtrails came to talk with me and recorded a video of our conversation.

There are a number of websites listed below that critique or debunk the chemtrail conspiracy theories. See for example:

Learn more about geoengineering.