Oceans

ocean

Radium levels suggest Arctic Ocean chemistry is changing

Rising temperatures have already caused changes in the Arctic environment, like diminishing sea ice and thawing permafrost. Now, it appears that sea-ice loss could be throwing Arctic Ocean chemistry out of whack.

24 Apr 2018

Disrupting the deep: Ocean warming reaches the abyss

Since the 1970s, just 7 percent of the heat associated with humancaused warming has melted snow and ice or warmed the land and atmosphere. The other 93 percent was absorbed by the oceans, where temperatures are now increasing at nearly all latitudes and depths, threatening to fundamentally alter our planet by disrupting ocean circulation. 
20 Mar 2018

Gyres spin up, currents get muddled

In addition to polynya formation and warming-induced surface freshening, other factors may also impact open-ocean convection in the Southern Ocean. The warming atmosphere is shifting global climatic zones and their associated wind fields poleward in both hemispheres. In the Weddell Sea Gyre, one of two clockwise-spinning circulation patterns in the Southern Ocean, this shift has resulted in a dramatic increase in wind stress curl (the strength of the wind’s influence on ocean water flow) over the past two years.

20 Mar 2018

Heating up Enceladus' ice-covered ocean

Saturn’s sixth-largest moon, Enceladus, is covered by ice, but just beneath its icy surface lies an ocean of liquid water. New research suggests that this internal ocean may be maintained in a liquid state by heat generated by tidal friction within the moon’s fragmented, rocky core.

08 Mar 2018

Driftwood reveals ancient Arctic currents and sea-ice levels

Arctic driftwood up to 12,000 years old is giving scientists a better understanding of how ocean currents and sea ice in the far north have changed through the Holocene. In a new study, published in the Journal of Geophysical Research: Oceans, scientists at the University of Oxford in England studied more than 900 pieces of driftwood collected from Arctic shorelines since the 1950s to investigate how shifting Arctic Ocean currents help melt or fortify sea ice.

28 Dec 2017

Ancient wildfires suggest rising atmospheric oxygen helped end past ocean anoxia

Many times throughout Earth’s history, oxygen levels in the world’s oceans have decreased dramatically in episodes called oceanic anoxic events (OAEs), which have caused massive marine die-offs. In the Early Jurassic, for example, the Toarcian OAE has been linked with the extinction of many ammonite species and other sea life. However, how such episodes end remains largely unclear to scientists.

22 Aug 2017

A new — and more toxic — normal? Harmful algal blooms find new habitats in changing oceans

A massive and deadly algal bloom along the West Coast of North America in 2015 is just one example of the growing number of severe algal blooms that are occurring throughout the world's oceans. Scientists are studying how toxic species are adjusting to a warming climate. 

16 Jan 2017

Pluto may still have liquid ocean

Last year, images from NASA’s New Horizons flyby of Pluto revealed geologic activity that suggested a liquid ocean may have once lurked beneath the dwarf planet’s icy crust. But whether it still exists in that state, or had frozen, remained a question. According to a new study published in Geophysical Research Letters, it may still be partially liquid.

14 Nov 2016

Drilling for gold inside a submarine volcano

Earth scientists have been given the green light to drill into an active submarine volcano for the first time, with the hope of discovering substantial new reserves of valuable metals, as well as new forms of extreme life.

31 Oct 2016

Tiny ocean bacteria could play big role in climate

In the 1990s, researchers identified the most abundant group of organisms in the ocean as Pelagibacterales, a class of free-living bacteria that live in surface waters as a microscopic but major part of the phytoplankton community. Now, a new study suggests that Pelagibacterales could play an important role in the global climate cycle by producing dimethylsulfide (DMS), an organosulfur compound that stimulates cloud formation when it gets into the atmosphere.

05 Sep 2016

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