Contrails from the plane in the sky

We all know about the harmful effects that motor vehicles and various types of factories have on our environment. When someone mentions global warming, the first things on our mind are probably carbon dioxide, greenhouse gas emissions, gasoline, exhaust pipes, and loud car engines. However, the traffic on our streets and highways is not the only form of traffic that puts our environment in danger and warms the atmosphere. There has been a lot of talk recently in the scientific communities about the negative effects if airplane contrails. Studies show that contrails induce a warming effect that is hazardous to the global climate. Let’s explain why aviation has a negative impact on our climate.

During the flight, an aircraft releases certain amounts of humidity that form a cloud-like structure, high up in the atmosphere. These cloud-like formations are known as contrails, which is short of condensation trails. The condensation trails can’t be formed at every height as they require special conditions. Contrails are formed only at certain heights where the air temperature, humidity, pressure, and other atmospheric conditions allow for their formation to happen. For instance, military aircraft can avoid leaving contrails to prevent detection by enemy forces by flying at a certain height. However, commercial airplanes don’t have a choice — they need to leave contrails at some point.

The warming effect of contrails originates from their position in the atmosphere, their density, and their structure. The condensation trail of an airplane contains a large number of soot particles. The name “soot particles” stands for a mixture of various particles with different chemical makeup. A significant proportion of these particles are small parts of airplane fuel that didn’t combust. Apart from that, in soot particles, there is a large amount of carbon and chemicals that are a product of fuel burning. None of these particles is dangerous on their own, but when in the right position in the atmosphere, they can be. These small particles induce ice formation in the air, thus creating fine, thin, cirrus clouds high up in the air. The cloud-like structure made by airplanes creates the warming effect that worsens global warming. Studies show that contrails could harm our climate more than a large number of motor vehicles. Luckily, NASA and the German Aerospace Center are studying this phenomenon and working towards a solution.

Can This Warming Effect of Contrails Be Somehow Controlled or Reduced?

This problem has been discovered fairly recently, and science needs more information on it. In addition, the problem is more complicated than it seems at first. In this early stage, science offers only two ways in which this contrail problem can be treated. The first method would be an invention of a jet fuel that would leave fewer soot particles with different chemical makeup. This approach to the problem would reduce the contrail warming effect significantly and very fast. However, the problem is that a type of jet fuel that wouldn’t produce soot particles is not easy to make. All the experiments so far have shown fairly satisfying results. On the other hand, there is one more way that we could approach this problem — the avoidance of air travel altogether.

Of course, avoiding air travel is no permanent solution. It would, however, be a smart, temporary method of dealing with contrails’ negative effects. Many scientists and academics are joining in the discussion on this method. It seems that avoiding air travel until some “green jet fuel” is invented is the best we can do at this point. Unfortunately, all new green solutions for jet fuel that have been developed recently also produced some soot particles. These fuels did produce fewer soot particles but still enough to turn into ice crystals. It seems that we will have to wait a bit more until these new fuels are perfected. In the meantime, NASA scientist Dr. Peter Kalmus, together with numerous academics, decided to avoid air travel as much as possible.

The Positive Side of the Story

The story about the contrails is not all that dark, there is one positive thing about them that gives us hope. Contrails and their environmental effects have a very short lifespan! They induce a lot of damage, but they don’t last long themselves. If we could find a solution for contrails in the form of a jet fuel green substitute, the negative effects of contrails would clear up fast. These cloud-like formations do produce the warming effect, but their nature is nothing like the nature of the gas emissions that create the greenhouse effect. Once the contrails cease to exist, the issues caused by them would also perish — scientists believe that the negative effects of contrails would need only decades to become a thing of the past.


Our modern way of life creates so much pollution — we pollute the environment with our cars, planes, fuels, factories, plastics, and various chemicals. The only optimistic thing in the story of global warming is that either the substitutes for the things that cause pollution already exist or are soon going to be perfected. We now live at a point in time when we can choose — we can start changing our habits, our way of life, the way we travel, the materials we use; or we can watch our planet die. There maybe isn’t a solution for contrails yet, but that doesn’t stop us from flying only when it’s necessary. If we reduced the frequency of our flights, our lives wouldn’t be that different; not a lot would change really. Every time we find out something new, we have a new choice to make. The study conducted by NASA showed that air traffic has an increasing warming effect on our climate. Now that we have information about contrail effects backed up by the best scientists in the world, we are obliged to think about the problem and act appropriately.