Aircraft tracks affect time

2002/08/08 Galarraga Aiestaran, Ana - Elhuyar Zientzia

• Garraioak
• Aeronautika
• Klima

The white footprint of the planes consists of condensed water vapors and small particles. This footprint quickly disappears in dry air, but if there is a lot of moisture it spreads like cirrus. Cirrus clouds are fine whitish clouds and it is known that this type of natural clouds, reflecting the rays of the sun, reduce the temperature during the day. At night, however, they do not let escape the heat of the Earth, so the temperature is usually higher when there are emotions than with the clean sky.

According to scientists, in areas of heavy air traffic, the influence of the footprint left behind by planes should be similar to that of the circus. And the opportunity that followed the attack was not wasted. Taking advantage of the fact that almost all the planes were on land from September 11 to 14, the night and daytime temperatures of those three days were measured and compared to the temperatures of the days when a similar time was made in September 1971 to 2000. The result was clarifying: on days without plane, the difference between the night minimum and the daily maximum was a greater degree than when there were planes. And the difference was even greater when compared with data from the three days before and after those three, with a difference of 1.8°C.

In the atmosphere as a whole, these temperature changes seem insignificant, but can be taken into account in areas with very high air traffic. In addition, the impact may be even greater in the future, as in some areas an increase of 5% per year of air traffic is expected. Although the results of the research are significant, researchers still know very little about the tracks left by the planes, so they cannot be taken into account when developing climate models.

The research has been published in the journal Nature.