I was unaware that the contrails left by planes in the air during their flight also generate pollution for us. These contrails that we see are water vapor that condenses like ice; they are produced in the combustion of jet engines and are generated according to the conditions of the air through which the planes fly.
These contrails trap and absorb part of the heat that would otherwise go into space, and therefore contribute to warming our surroundings. And they stay in the air for a few minutes, hours, or even a day.
In addition, this situation worsens at night because the temperature is lower and the contrails remain for a longer time even if we do not see them.
The aeronautical sector is responsible for 2.4% of the CO2 we emit into the atmosphere, and now everything is analyzed in more detail to see ways to reduce this pollution.
According to the latest estimates by scientists, these contrails could account for around 50% of the pollution generated by airplanes, and if they can be reduced, it would be a step forward in the fight against CO2 emissions. And on this path all steps count.
The positive part of this "problem" is that contrails do not always occur and it is now better known under what conditions they are generated. Special atmospheric conditions of humid, cold and super-saturated air are required to form ice.
Knowing the situation of the air in the atmosphere the trajectory of the aircraft can be slightly modified and avoid a large part of the contrails that are produced. And that is a low cost and very effective solution.
The modification of the trajectory can be to vary the height of the flight a little or slightly modify its trajectory, and that varies very little the cost of fuel per passenger. It’s also necessary to modify the software that controls the flight of the plane and put some sensors on it, and none of that is excessively expensive.
Aircraft construction companies and operators (Airbus, Lufthansa, etc…) are more than interested and working on the issue.
I have no doubt that in a reasonably short time the combustion results of their engines will improve, but they still have the unfinished business of moving their engines with non-polluting fuels.
That is a more complex challenge that will take longer to implement. Many thousands of tons of alternative fuel are required for today's flights.
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