The transatlantic jet trails visible from space: How 'contrails' can stay in the sky for up to 14 hours

PUBLISHED: 21:13 EST, 17 June 2012 | UPDATED: 05:08 EST, 18 June 2012
Like a giant game of crosses without the naughts, these incredible jet engine trails can be seen criss-crossing the Atlantic from space.
NASA's Terra satellite captured these two amazing images of aircraft trails, or 'contrails' as they are known, spreading across the sky off the coast of Newfoundland, Canada.
The spectacular effect forms in the wake of passing aircraft due to the extra particles and water vapor contained in their exhaust.
NASA said these it has observed these clusters of contrails lasting as long as 14 hours, though most get a shorter lifespan of four to six hours.
Jet trails: NASA's satellite captured the jet trails, pictured, criss-crossing the Atlantic on May 26
Jet trails: NASA's satellite captured the jet trails, pictured, criss-crossing the Atlantic on May 26
These photographs, taken over two hours on May 26, capture contrails that were likely caused by commercial aircraft flying west to North America from the UK and Europe.
The contrails are arrayed in X-shaped patterns and a cirrus cloud is visible to the left of both images.
The airplane signatures with distinct edges are visible in the first, older image, but two hours later have grown wispier and spread outward as winds have blown them south and east.
 

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The temperature and humidity of the air affects how long contrails last - when the air is dry, they remain visible for mere seconds or minutes.
But when the air is humid, as was the case here, contrails can be long-lived and spread outward until they become difficult to distinguish from naturally-occurring cirrus clouds.
Faded: A second image, pictured, captured two hours later shows the jet trails spreading and growing wispier
Faded: A second image, pictured, captured two hours later shows the jet trails spreading and growing wispier
Climate scientists are fascinated by long-lived, spreading contrails because they reflect sunlight and trap infrared radiation.
A contrail in an otherwise clear sky reduces the amount of solar radiation that reaches Earth’s surface, while increasing the amount of infrared radiation absorbed by the atmosphere.
These opposing effects make it difficult for scientists to pin down the exact effect contrails have on climate.
'Overall, contrails create additional cirrus cloud cover,' said Patrick Minnis, a senior scientist at NASA's Langley Research Center.
'Current estimates indicate that contrails have a small warming effect, but the extent of the additional coverage and the amount of warming remain quite uncertain.'
In 2004, Mr Minnis published a study of surface observations that found cirrus cloud cover had increased by 3 per cent between 1971 and 1995 over the United States, the most recent data available.
The two new pictures were taken by the Terra satellite's Moderate Resolution Imaging Spectroradiometer, used for photographing clouds and atmospheric features.