Jason Vandehey / shutterstock
Researchers have long used such techniques to learn about currents and tides.
Coral affected by black band disease, Bahamas.
James St. John/Flickr
Infectious diseases are a normal part of ocean ecosystems, just as they are on land. But climate change is altering the oceans in ways that could make marine diseases spread farther and faster.
The oceans are teeming with life and potential – but the high seas are still largely ungoverned.
The open oceans are the world's "wild west", falling outside any nation's jurisdiction. UN negotiations are aiming to draft new laws for the high seas.
An Amphipod at 8,000 metres.
From time-shifting earthquakes to bizarre creatures, the crushing depths of the hadal zone are another world.
The land may be dry, but Western Australia’s waters are full of life.
The Great Barrier Reef might get all the attention, but what about our western coral reefs? Warmer waters and human impacts mean these reefs are in trouble.
A Japanese fish found in Washington after hitching a ride in a boat sent across the Pacific Ocean by the 2011 tsunami.
The 2011 Japan tsunami illustrates how more marine creatures are crossing the oceans than ever before - and not all of them are friendly travellers.
Anse Source d'Argent beach, La Digue island, Seychelles is one of Africa’s finest beaches.
Africa has some wonderful beaches. A serious traveller should visit at least one of them once in a lifetime.
Early signs of bleaching coral in Kaheohe Bay Hawaii, August 2015.
XL Catlin Seaview Survey / Underwater Earth
Many corals can't make it through the bleaching events caused by warming ocean waters. But some can – and scientists are trying to learn more about the sources of their resilience.
Deep seabed mining for minerals might soon become a reality.
Mining the deep oceans for minerals may soon become a reality, but the risks involved are many. So who is able to regulate this emerging industry?
Spot the opera house.
The dust storm that turned Sydney red in 2009 triggered plankton blooms in the Tasman Sea, demonstrating how we might fertilise the ocean to take up more carbon dioxide.
Gamba Grass is altering fire regimes in the Top End, threatening human life and property, natural assets including Kakadu and Litchfield National Parks, and compromising savanna burning programs.
One of the Australian government's new research priorities is "environmental change". But can be hard to know how to tackle such huge and interlinked issues as climate change and species extinctions.
The reefs of Indonesia - part of the Coral Triangle - could lose many of their species thanks to climate change.
How will climate change affect life in the oceans? New research shows that the answer is likely good and bad.
Too many fish in our seas, like this Pacific bluefin tuna, are being lost to over-fishing – but better management can help.
Over-fishing is a massive environmental and economic challenge. Fortunately, there are new solutions being trialled – including in a tuna hotspot in the Pacific.
Expect to see more ships on the horizon, as global shipping booms. But how well are we measuring and governing what happens at sea?
As the world's land-based economies struggle with around 2% GDP growth, the global marine economy – often talked about as "the blue economy" – is a bright light on the horizon.
The Great Southern Reef is unique, beautiful and contributes significantly to Australia’s culture and economy. However, few of us realise the magnitude and value of this gem right at our doorstep.
T. Wernberg 2002
The Great Southern Reef covers 71,000 square km and contributes more than A$10 billion to Australia's economy each year.
Where there are groups of seals, there are sharks.
Massachusetts Office of Energy and Environment
A rash of white shark attacks this summer points to a rebounding population in the US – a sign of healthier oceans and the need to coexist with this apex predator.
The Southern Ocean is remote, cloudy – and full of plankton.
These tiny organisms play a big role in regulating the Earth's climate.
The moment a shark encounters Australian champion surfer Mick Fanning.
AAP Image/World Surf League, Kirstin Scholtz
Although frightening, the footage of Mick Fanning at Jeffreys Bay is a reminder that sharks are present in the oceans, and that the vast majority of interactions between people and sharks end without fatality or injury.
Sensationalized shark attacks skew the facts.
'Shark' via www.shutterstock.com
Millions tune in to Shark Week each year, but many walk away with the wrong impressions.
Acehnese fishers are among the quarter of the world’s population who live on the coast, and for whom climate-driven changes to the oceans would make life much harder.
Hotli Simanjuntak/EPA/AAP Image
Failing to stick to the world's agreed global warming limit of 2C won't just affect the atmosphere - it will play havoc with the oceans too, potentially ruining ecosystems on which much of humanity depends.