How much water on Earth? Exactly 1.33 bn cubic km
Washington: For the romantics, love is as deep as the ocean. And now, researchers at the Woods Hole Oceanographic Institution (WHOI) have actually tried to quantify the age-old query— How deep is the ocean?
They’re also tackling an even more intriguing—if less romantic—question— What is the volume of the Earth’s oceans?
And the answer is 1.332 billion cubic kilometres, says Matthew Charette, an associate scientist in WHOI’s Department of Marine Chemistry and Geochemistry who is part of a research effort to audit all the water on the planet.
“A lot of water values are taken for granted. If you want to know the water volume on the planet, you Google it and you get five different numbers, most of them 30- or 40-year-old values,” he said.
Using satellite measurements, the researchers have come with up the new ocean volume figure.
The researchers report that the world’s total ocean volume is less than the most recent estimates by a volume equivalent to about five times the Gulf of Mexico, or 500 times the Great Lakes.
While that might seem a lot at first glance, it is only about 0.3 percent lower than the estimates of 30 years ago.
Most recently, researchers have pioneered the use of satellites to calculate ocean volume.
The trend toward a progressive lowering of volume estimates is not because the world’s oceans are losing water.
Instead, it reflects a greater ability to locate undersea mountain ranges and other formations, which take up space that would otherwise be occupied by water.
Satellite measurements reveal that ocean bottoms “are bumpier and more mountainous than had been imagined,” said co-investigator Walter H.F. Smith.
He noted that as measurements improve, ocean-volume values are lowering, emphasizing that this does not reflect an actual lessening of water but a more accurate accounting of undersea formations.
Satellite-based radar cannot “see” the ocean bottom, he explains. Rather, it measures the ocean surface, which reflects what lies beneath.
The satellite project has covered virtually all the world’s oceans, except for some areas of the Arctic that are covered with ice, he said.
The result is a “new world map” of the oceans, he added.
“Matt and I are seeing a better picture of the shape and volume of oceans,” said Smith
But satellite measurements have their shortcomings.
"There is a problem of spatial resolution, like an out-of-focus camera. We’re measuring the sea surface that is affected by mountains, but we’re seeing only really big mountains, and in a blurry way. The resolution is 15 times worse than our maps of Mars and the moon,” he said.
Consequently, the researchers say, more ship-based measurements are needed to augment and “fine tune” the satellite data.
And so far, ship-based sonar and other instrumentation have mapped only 10 percent of the Earth’s seafloor.
“We have gaps in echosounding measurements as wide as New Jersey,” said Smith.
The study’s calculation of the ocean’s mean depth is 3,682.2 meters—that’s 21-to-51 meters less than previous estimates.
The study is published in the current issue of the journal Oceanography.
More from India
More from World
More from Sports
More from Entertaiment
- Mathura SSP receives death threat letter, message for PM Modi
- Reservation issue: Police register case against Bainsla, 20 others
- Zee Media exclusive chat with 'Welcome to Karachi' cast
- Zee Media exclusive interview with Haryana CM Manohar Lal Khattar
- UP Minister allegedly threatens, abuses Gonda businessman
- Manali: Heavy corruption found in environmental taxes
- Aapke Sitare: Astro prediction for May 24, 2015
- Watch: Fast N Facts @ 7:30pm
- One year of Modi govt: How satisfied is the common man?
- Five unmanned parachutes spotted over Mumbai airport
- Jaipur girl Mini Rajpal wins Miss India Deaf 2015!
- UP: Jammu-bound Muri Express derails in Kaushambi
- One year of Modi govt: How satisfied is the common man? Part-2
- Mumbai architecture creates double decker bus from scrap!
- CBSE Board Class 12th Exam Results 2015 declared
- 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
- Organisation demands re-examination of AIPMT 2015
- Death threat to PM Narendra Modi ahead of Mathura rally sends police into tizzy
- Kejriwal completes 100 days in office, AAP says centre 'shadow boxing' over row with LG
- CBSE Class 12th Board Results 2015 to be announced on Monday, May 25
- Check cbseresults.nic.in for CBSE Class 12 result 2015
- LIVE - Cbse.nic.in & cbseresults.nic.in Class 12th XII Results 2015: CBSE Board Class 12th XII Exam Results 2015 to be announced shortly
- Online filing of applications for UPSC civil services exam begins
- Heatwave claims over 550 lives so far, Delhi saw hottest day
- Not just today, Muslims feeling alienated since 1947: Najma Heptulla
- Police register case against Bainsla, 20 others as Gujjar agitation continues
- Pakistan criticizes Defence Minister Parrikar's terrorism remarks