Climatologists have found that the bomber planes used in World War II may have changed the temperature of the ground below with the contrails they left in their wake. Contrails are air vapor trails left by certain aircraft, and they affect climate by trapping heat below like a thermal barrier while reflecting incoming solar heat back up into the atmosphere. Research has shown that, by measuring the contrail information which was tracked by pilots, climatologists can measure the effect they had on global climate.

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