Researchers Wednesday urged sailors to become "citizen oceanographers" and help scientists better understand some of the world's wildest seas where ships and even planes disappear without trace.
An Australian-led study said that despite technology such as GPS navigation and advanced research vessels with modern capabilities, much of the world's oceans remains under-explored, with cost a key impediment to knowing more.
"Notwithstanding satellite constellations, autonomous vehicles, and more than 300 research vessels worldwide, we lack fundamental data relating to our oceans," said the study published in the journal PLoS Biology.
"These missing data hamper our ability to make basic predictions about ocean weather, narrow the trajectories of floating objects, or estimate the impact of ocean acidification and other physical, biological, and chemical characteristics of the world's oceans."
The lack of knowledge has been evident most recently in the fruitless hunt for Malaysia Airlines Flight MH370, which is believed to have crashed in the largely unmapped southern Indian Ocean off Western Australia six months ago.
"Even a modern jetliner can disappear in the ocean with little or no trace, and the current costs and uncertainty associated with search and rescue make the prospects of finding an object in the middle of the ocean daunting," it said.
Federico Lauro, a University of New South Wales microbiologist and national sailing champion who led the study, said cost was a key factor in better understanding oceans.
But there was a large pool of sailors who could contribute cheaply, using small instruments fitted to yachts at a fraction of the cost of running specialised research vessels.
"The world's oceans are largely unexplored and we have a shortage of oceanographic data because it is financially and logistically impractical for scientists to sample such vast areas," he said.
"But with the right equipment, citizen scientists could gather large quantities of information as they sail around the world."
- 'Citizen science' -
 Lauro last year led a scientific expedition across the Indian Ocean aboard S/Y Indigo V, a 61-foot (18-metre) sailing yacht, to pioneer this method of data collection.
The expedition, involving researchers from institutions in Australia, Canada, Singapore, Denmark and the US, demonstrated that the cost-effective approach could work.
During the 6,500 nautical mile "proof of concept" voyage from South Africa to Singapore, the team regularly took measurements and collected samples of tiny marine microbes.
The four-month journey cost less than two days of ship-time aboard an oceanographic research vessel, which typically costs more than US$30,000 per day to operate, excluding the cost of scientists, engineers, and the research itself.
Lauro said the thousands of yachts at sea each year could form a global monitoring network, collecting temperature and conductivity measurements, monitoring the weather and recording sightings of debris.
They could also collect samples of the tiny marine microbes, including bacteria and plankton, that are the foundation of the food web and vital indicators of an ocean's health.
"By using what's known as 'citizen science', Indigo V Expeditions set out to prove that the concept of crowdsourcing oceanography can solve the great data collection bottleneck," said Lauro.