Ocean asteroid could damage ozone layer
London: If a medium-sized asteroid were to land in the oceans a tsunami wouldn`t be the only worry, say scientists– Earth’s ozone layer could be at risk too.
A new computer simulation suggests that the water vapour and sea salt thrown up by the impact could damage the protective ozone layer, leading to record levels of ultraviolet radiation that could threaten human civilisation.
Elisabetta Pierazzo of the Planetary Science Institute in Tucson, Arizona, and colleagues used a global climate model to study how water vapour and sea salt thrown up from an impact will affect ozone levels for years after the event.
They focused on medium-sized asteroids, either 500 metres or 1 kilometre wide. To date, 818 asteroids that are at least 1 km wide have been discovered on orbits that could take them close to Earth.
These objects are on orbits that give them a very small probability of hitting Earth in the near future. However, estimates of the asteroid population suggest dozens more have yet to be found, with unknown orbits that could intersect with the Earth.
To get a sense of how much water might be jettisoned into the atmosphere if these asteroids hit the ocean, the team modelled what would happen if they reached Earth`s atmosphere at a clip of 18 kilometres per second, an average speed expected for a near-Earth object, and hit the ocean in the northern hemisphere at a 45-degree angle.
As expected, the simulations showed that the larger, 1-km asteroid created the bigger splash, throwing 42 trillion kilograms of water and vapour – enough to fill 16 million Olympic-sized swimming pools – across an area more than 1000 kilometres wide and up to hundreds of kilometres above the Earth`s surface.
Once in the atmosphere, the water, together with compounds containing chlorine and bromine from vaporised sea salts, destroyed ozone above the Earth`s atmosphere at a much faster rate than it is naturally created.
Some simulated impacts created depletions that were still felt across the whole Earth a year later.
"It will produce an ozone hole that will engulf the entire Earth," New Scientist quoted Pierazzo as saying.
The study has been published in the journal Earth and Planetary Science Letters.
More from India
More from World
More from Sports
More from Entertaiment
- Zee Media exclusive chat with 'Welcome to Karachi' cast
- Reservation issue: Police register case against Bainsla, 20 others
- Zee Media exclusive interview with Haryana CM Manohar Lal Khattar
- UP Minister allegedly threatens, abuses Gonda businessman
- Manali: Heavy corruption found in environmental taxes
- UP: Jammu-bound Muri Express derails in Kaushambi
- Five unmanned parachutes spotted over Mumbai airport
- Aapke Sitare: Astro prediction for May 24, 2015
- Watch: Fast N Facts @ 7:30pm
- Dawood's intercepted phone calls prove yet again he is in Pakistan
- One year of Modi govt: How satisfied is the common man?
- Jaipur girl Mini Rajpal wins Miss India Deaf 2015!
- CBSE Board Class 12th Exam Results 2015 declared
- Mumbai architecture creates double decker bus from scrap!
- One year of Modi govt: How satisfied is the common man? Part-2
- IPL 2015 Final: MI vs CSK - As it happened...
- CBSE.nic.in 12th XII Results 2015: CBSE Board (cbseresults.nic.in) Class 12th XII Exam Results 2015 to be announced on May 25
- Heatwave continues in North India; death toll in Andhra Pradesh, Telangana more than 400
- IPL 2015 final: Mumbai Indians thrash Chennai Super Kings by 41 runs to lift second title
- Heatwave claims over 550 lives so far, Delhi saw hottest day
- LIVE - Cbse.nic.in & cbseresults.nic.in Class 12th XII Results 2015: CBSE Board Class 12th XII Exam Results 2015 to be announced shortly
- Check cbseresults.nic.in for CBSE Class 12 result 2015
- Cbse.nic.in & cbseresults.nic.in Class 12th XII Results 2015: CBSE Board Class 12th XII Exam Results 2015 declared
- Two dead, over 100 injured as Muri Express derails in UP; Prabhu announces Rs 2 lakhs ex-gratia for kin of dead
- Mathura rally: PM Modi slams 'corrupt' UPA regime, lauds NDA govt's efforts in past one year
- CBSE Class 12 results out: Here's how you can check
- PM Narendra Modi's Mathura rally: As it happened
- Check WBBSE (wbresults.nic.in) Class 12th Results: West Bengal Board (wbscvet.org) Higher Secondary Class XII Vocational Results to be declared today at 4 PM
- Police register case against Bainsla, 20 others as Gujjar agitation continues
- CBSE Board 12th XII Results 2015: Cbse.nic.in & cbseresults.nic.in Class 12th XII Exam Results 2015 to be announced today at 12 Noon