ScienceDaily: Oceanography News

Underwater springs reveal how coral reefs respond to ocean acidification

Mon, 17 Jun 2013 16:08:08 EDT

Ocean acidification due to rising carbon dioxide levels will reduce the density of coral skeletons, making coral reefs more vulnerable to disruption and erosion, according to a new study of corals growing where submarine springs naturally lower the pH of seawater. The study is the first to show that corals are not able to fully acclimate to low pH conditions in nature.

Jet stream changes cause climatically exceptional Greenland Ice Sheet melt

Mon, 17 Jun 2013 11:12:12 EDT

Scientists have shown that unusual changes in atmospheric jet stream circulation caused the exceptional surface melt of the Greenland Ice Sheet in summer 2012.

New 'embryonic' subduction zone found

Mon, 17 Jun 2013 10:46:46 EDT

A new subduction zone forming off the coast of Portugal heralds the beginning of a cycle that will see the Atlantic Ocean close as continental Europe moves closer to America.

'Cold snap' 116 million years ago triggered marine ecosystem crisis

Sun, 16 Jun 2013 15:52:52 EDT

A "cold snap" 116 million years ago triggered a similar marine ecosystem crisis to the ones witnessed in the past as a result of global warming, according to new research. The international study confirms the link between global cooling and a crash in the marine ecosystem during the mid-Cretaceous greenhouse period.

Study of oceans' past raises worries about their future

Fri, 14 Jun 2013 11:16:16 EDT

Scientists have now completed the first global study of changes that occurred in a crucial component of ocean chemistry, the nitrogen cycle, at the end of the last ice age. The results of their study confirm that oceans are good at balancing the nitrogen cycle on a global scale. But the data also shows that it is a slow process that may take many centuries, or even millennia, raising worries about the effects of the scale and speed of current changes in the ocean.

Warm ocean drives most Antarctic ice shelf loss

Thu, 13 Jun 2013 14:28:28 EDT

Ocean waters melting the undersides of Antarctic ice shelves, not icebergs calving into the sea, are responsible for most of the continent's ice loss, a new study has found.

'Tailing' spiny lobster larvae to protect them

Thu, 13 Jun 2013 09:23:23 EDT

In a new study of spiny lobsters scientists studied the larval dispersal of this species in the Caribbean. The goal of the study was to describe the sources, sinks, and routes connecting the Caribbean spiny lobster metapopulation. The results led the team to propose marine resource management strategies that incorporate larval connectivity and "larval lobster credits" to sustain and rebuild exploited marine populations.

Rapid adaptation is purple sea urchins' weapon against ocean acidification

Wed, 12 Jun 2013 18:40:40 EDT

In the race against climate change and ocean acidification, some sea urchins may still have a few tricks up their spiny sleeves, suggesting that adaptation will likely play a large role for the sea creatures as the carbon content of the ocean increases.

Iron fertilization, process of putting iron into ocean to help capture carbon, could backfire

Wed, 12 Jun 2013 14:48:48 EDT

A study suggests that iron fertilization, the process of putting iron into the ocean to encourage the growth of carbon dioxide capturing alga blooms, could backfire.

Life underground: Microbes active far beneath seafloor

Wed, 12 Jun 2013 14:47:47 EDT

Genetic researchers have revealed active bacteria, fungi and other microbes living in 5 million-year-old ocean sediment.

When will the next megathrust hit the west coast of North America?

Wed, 12 Jun 2013 13:31:31 EDT

A new study presents our first glimpse back in geologic time of the recurrence interval of large and megathrust earthquakes impacting the vulnerable BC outer coastline.

Researchers sequence the genome of global deep ocean

Wed, 12 Jun 2013 13:31:31 EDT

Biologists have started to sequence the genome of the global deep ocean. They are using more than 2,000 samples of microorganisms collected in the Atlantic, Indian and Pacific Oceans during the Malaspina Expedition. This collection of marine microbial genomic, the first in the world on a global scale, will provide new clues about a reservoir of biodiversity yet to explore.

Carbon dioxide absorption in Antarctic seas

Wed, 12 Jun 2013 13:26:26 EDT

Diatoms stuff more iron into their silica shells than they actually need. As a result, there’s not enough iron to go around, and the added iron during fertilization experiments may stimulate less productivity than expected. The study also says that the removal of iron through incorporation into diatom silica may be a profound factor controlling the Southern Ocean’s bioavailable pool of iron, adversely affecting the ecosystem.

Fukushima accident raised levels of radioactive strontium off the east coast of Japan by up to 100 times

Tue, 11 Jun 2013 08:42:42 EDT

Researchers in Spain have studied the spread of radioactive strontium in the coastal waters of eastern Japan during the three months following the Fukushima nuclear accident, which happened in March 2011. The samples analysed show the impact of the direct release of radioactive materials into the Pacific Ocean, and indicate that the amount of strontium-90 discharged into the sea during those three months was between 90 and 900 Tbq (terabecquerels), raising levels by up to two orders of magnitude. The highest concentrations were found to the north of the Kuroshio current, which acts as a barrier preventing radioactive material from being carried to lower latitudes.

Leakage of carbon from land to rivers, lakes, estuaries and coastal regions revealed

Mon, 10 Jun 2013 09:51:51 EDT

When carbon is emitted by human activities into the atmosphere it is generally thought that about half remains in the atmosphere and the remainder is stored in the oceans and on land. New research suggests that human activity could be increasing the movement of carbon from land to rivers, estuaries and the coastal zone indicating that large quantities of anthropogenic carbon may be hidden in regions not previously considered.

Amazon forest fire risk to increase in 2013

Fri, 07 Jun 2013 15:39:39 EDT

University and NASA researchers predict that the severity of the 2013 fire season will be considerably higher than in 2011 and 2012 for many Amazon forests in the Southern Hemisphere. The outlook is based on a fire severity model that produced a successful first forecast in 2012.

Stranded orcas hold critical clues for scientists

Fri, 07 Jun 2013 13:10:10 EDT

The development of a standardized killer-whale necropsy system has boosted the complete data from killer-whale strandings from two percent to about 33 percent, according to a recent study.

Earthquake acoustics can indicate if a massive tsunami is imminent

Thu, 06 Jun 2013 15:51:51 EDT

Scientists have identified key acoustic characteristics of the 2011 Japan earthquake that indicated it would cause a large tsunami. The technique could be applied worldwide to create an early warning system for massive tsunamis.

Predicting the future of coral reefs in a changing world

Thu, 06 Jun 2013 14:06:06 EDT

Scientists have described for the first time the biological process of how corals create their skeletons, which form massive and ecologically vital coral reefs in the world's oceans. They identified specific proteins secreted by corals that precipitate carbonate to form the corals' characteristic skeleton.

Where trash accumulates in the deep sea

Wed, 05 Jun 2013 14:43:43 EDT

Surprisingly large amounts of discarded trash end up in the ocean. Plastic bags, aluminum cans, and fishing debris not only clutter our beaches, but accumulate in open-ocean areas such as the "Great Pacific Garbage Patch." Now, new research shows that trash is also accumulating in the deep sea, particularly in Monterey Canyon.

Pollution controls increase beach attendance, study shows

Wed, 05 Jun 2013 13:01:01 EDT

Southern California beaches with storm drain diversion systems attract millions more people annually, a new study shows.

NASA's IceBridge mission contributes to new map of Antarctica

Wed, 05 Jun 2013 09:07:07 EDT

A new dataset called Bedmap2 gives a clearer picture of Antarctica from the ice surface down to the bedrock below. Bedmap2 is a significant improvement on the previous collection of Antarctic data -- known as Bedmap -- that was produced more than 10 years ago.

Human deforestation outweighs climate change for coral reefs

Wed, 05 Jun 2013 07:17:17 EDT

Better land use is the key to preventing further damage to the world's coral reefs, according to new research. The study has important implications for Australia's Great Barrier Reef. The study authors write that preventing soil erosion and sediment pollution arising from human activities such as deforestation are crucial to reef survival.

The jewels of the ocean: Two new species and a new genus of octocorals from the Pacific

Mon, 03 Jun 2013 13:55:55 EDT

Two new beautiful species of octocorals and a new genus have been described from the well explored west coast of North America. Despite the 3,400 known species nowadays, these colorful marine jewels continue to surprise with new discoveries which calls for a detailed exploration of the remarkable biodiversity of octocorals.

Acceleration of ocean denitrification during deglaciation documented

Mon, 03 Jun 2013 11:39:39 EDT

As ice sheets melted during the deglaciation of the last ice age and global oceans warmed, oceanic oxygen levels decreased and "denitrification" accelerated by 30 to 120 percent, a new international study shows, creating oxygen-poor marine regions and throwing the oceanic nitrogen cycle off balance.

Hidden effects of climate change may threaten eelgrass meadows

Mon, 03 Jun 2013 09:23:23 EDT

Some research has shown that the effects of changes in the climate may be weak or even non-existent. This makes it easy to conclude that climate change will ultimately have less impact than previous warnings have predicted. But it could also be explained as direct and indirect effects cancelling each other out, as scientists show.

Catastrophic climatic events leave corals facing a decade-long fight for recovery

Sat, 01 Jun 2013 13:39:39 EDT

Coral reefs can take more than a decade to recover from catastrophic climatic events, with some species taking up to 13 years to recolonise their original habitats, scientists have discovered.

Acidifying oceans could spell trouble for squid

Sat, 01 Jun 2013 13:39:39 EDT

Acidifying oceans could dramatically impact the world's squid species, according to a new study. Because squid are both ecologically and commercially important, that impact may have far-reaching effects on the ocean environment and coastal economies, the researchers report.

North Atlantic hurricane forecast predicts above-average season

Sat, 01 Jun 2013 13:36:36 EDT

Scientists have developed a unique computer model with a knack for predicting hurricanes with unprecedented accuracy and are forecasting a season of above-average activity for 2013.

Mapping sea salt from orbit: Building better ocean and climate models

Fri, 31 May 2013 10:17:17 EDT

Climate is greatly influenced by the flow of heat energy carried by ocean currents. But precisely quantifying the mixing between the ocean and the atmosphere is hampered by a lack of detail in models of the ocean and of the water cycle. And in both models, knowing the salt content of the water is essential.

New maps show how shipping noise spans the globe

Thu, 30 May 2013 15:28:28 EDT

Scientists have modeled shipping noise on a global scale.

Why female loggerhead sea turtles always return to their place of birth

Thu, 30 May 2013 11:11:11 EDT

For a better protection of marine turtles, scientists are trying to understand why they return to their birthplace in order to reproduce after rather long distance migrations. Using molecular tools applied to turtles from the Cape Verde islands, scientists found females from different islands have different immune genes, suggesting that returning home to reproduce is linked to advantages in parasite resistance.

Thermal limit for animal life redefined by first lab study of deep-sea vent worms

Wed, 29 May 2013 19:09:09 EDT

Forty-two may or may not be the answer to everything, but it likely defines the temperature limit where animal life thrives, according to the first laboratory study of heat-loving Pompeii worms from deep-sea vents.

Recovery of Hawaiian green sea turtles still short of historic levels

Wed, 29 May 2013 13:35:35 EDT

Hawaiian green sea turtle populations have increased in recent years, but their numbers still fall far short of historic levels. A new report suggests that calls to lift protection for this species may be premature.

Arctic current flowed under deep freeze of last ice age, study says

Wed, 29 May 2013 13:34:34 EDT

During the last ice age, when thick ice covered the Arctic, many scientists assumed that the deep currents below that feed the North Atlantic Ocean and help drive global ocean currents slowed or even stopped. But in a researchers have now shown that the deep Arctic Ocean has been churning briskly for the last 35,000 years, through the chill of the last ice age and warmth of modern times.

Geochemistry survey at Chatham Rise reveals absence of modern day greenhouse gas emissions

Wed, 29 May 2013 10:16:16 EDT

Geochemistry analysis of fossil sediment injection structures off the New Zealand coast in February and March reveal no presence of modern day expulsions of methane gas, a potential contributor to global 'greenhouse effect' warming.

Historic sea-level change along New Jersey coastline mapped

Tue, 28 May 2013 18:10:10 EDT

A new study relied upon fossil records of marshland to reconstruct the changes in sea level along the New Jersey coast going back 10,000 years.

Scientists develop CO2 sequestration technique

Tue, 28 May 2013 14:37:37 EDT

Scientists have discovered and demonstrated a new technique to remove and store atmospheric carbon dioxide while generating carbon-negative hydrogen and producing alkalinity, which can be used to offset ocean acidification.

Fast-sinking jellyfish could boost the oceans' uptake of carbon dioxide

Tue, 28 May 2013 12:25:25 EDT

Increasing numbers of gelatinous plankton might help in mitigating the carbon dioxide problem. In field and laboratory experiments scientists have shown that dead jellyfish and pelagic tunicates sink much faster than phytoplankton and marine snow remains. Jellies are especially important because they rapidly consume plankton and particles and quickly export biomass and carbon to the ocean interior.

Study explores atmospheric impact of declining Arctic sea ice

Tue, 28 May 2013 10:58:58 EDT

New research explores the impact of ice free seas on the planet's atmospheric circulation.

Century-old ocean data provides further confirmation of global warming

Tue, 28 May 2013 10:45:45 EDT

A new NASA and university analysis of ocean data collected more than 135 years ago by the crew of the HMS Challenger oceanographic expedition provides further confirmation that human activities have warmed our planet over the past century.

Expedition to study ancient continental breakup west of Spain

Fri, 24 May 2013 10:42:42 EDT

An international team of scientists has embarked on a shipboard expedition to study how the Earth's crust was pulled apart in an area beneath the Atlantic Ocean off the coast of Spain.

Earth's mantle affects long-term sea-level rise estimates

Thu, 23 May 2013 14:37:37 EDT

New findings reveal that the U.S. shoreline -- from Virginia to Florida -- has been uplifted by more than 210 feet, meaning less ice melted than expected. This is big news for scientists who use the coastline to predict future sea-level rise.

NASA ships sensors for seafaring satellite to France

Thu, 23 May 2013 09:10:10 EDT

Three NASA-built instruments that are integral components of the next in a series of U.S./European ocean altimetry satellites have arrived in France for integration with their spacecraft in preparation for a 2015 launch. Jason-3 will extend the two-decade series of satellites that are tracking global sea level changes and enabling more accurate weather, ocean and climate forecasts.

Vast methane-based ecosystem uncovered

Wed, 22 May 2013 12:30:30 EDT

A marine research expedition has led to the discovery of perhaps the world's largest methane cold seep. The seep lies deep in the western North Atlantic Ocean, far from the life-sustaining energy of the sun. Mussels blanketing the the seep rely on bacteria that use the methane to make energy. The process, known as chemosynthesis, forms the basis for life in the harsh environment and could help scientists better understand how organisms can survive under these types of extreme conditions.

Study reveals how fishing gear can cause slow death of whales

Tue, 21 May 2013 19:42:42 EDT

Using a "patient monitoring" device attached to a whale entangled in fishing gear, scientists showed for the first time how fishing lines changed a whale's diving and swimming behavior. The monitoring revealed how fishing gear hinders whales' ability to eat and migrate, depletes their energy as they drag gear for months or years, and can result in a slow death.

Abundance and distribution of Hawaiian coral species predicted by model

Tue, 21 May 2013 10:57:57 EDT

Researchers have developed species distribution models of the six dominant Hawaiian coral species around the main Hawaiian Islands, including two species currently under consideration as threatened or endangered.

Amazon River exhales virtually all carbon taken up by rainforest

Mon, 20 May 2013 15:43:43 EDT

Woody plant matter is almost completely digested by bacteria living in the Amazon River. This tough stuff plays a major part in fueling the river's breath. The finding has implications for global carbon models, and for the ecology of the Amazon and the world's other rivers. Until recently, people believed much of the rainforest's carbon floated down the Amazon River and ended up deep in the ocean.

Roots of future tropical rainfall: Sea level influenced tropical climate during the last ice age

Sun, 19 May 2013 19:04:04 EDT

How will rainfall patterns across the tropical Indian and Pacific regions change in a future warming world? Climate models generally suggest that the tropics as a whole will get wetter, but the models don't always agree on where rainfall patterns will shift in particular regions within the tropics.

Topography of Eastern Seaboard muddles ancient sea level changes

Thu, 16 May 2013 18:20:20 EDT

The distortion of the ancient shoreline and flooding surface of the US Atlantic Coastal Plain are the direct result of fluctuations in topography in the region and could have implications on understanding long-term climate change, according to a new study.

World's biggest ice sheets likely more stable than previously believed

Thu, 16 May 2013 14:25:25 EDT

A new study suggests that the previous connections scientists made between ancient shoreline height and ice volumes are erroneous and that perhaps our ice sheets were more stable in the past than we originally thought. The study found that the Earth's hot mantle pushed up segments of ancient shorelines over millions of years, making them appear higher now than they originally were millions of years ago.

World's melting glaciers making large contribution to sea rise

Thu, 16 May 2013 14:25:25 EDT

While 99 percent of Earth's land ice is locked up in the Greenland and Antarctic ice sheets, the remaining ice in the world's glaciers contributed just as much to sea rise as the two ice sheets combined from 2003 to 2009, says a new study.

'Fish thermometer' reveals long-standing, global impact of climate change

Wed, 15 May 2013 13:15:15 EDT

Climate change has been impacting global fisheries for the past four decades by driving species towards cooler, deeper waters, according to scientists.

Fall warming on Antarctic Peninsula driven by tropically forced circulation

Wed, 15 May 2013 13:14:14 EDT

New research shows that, in recent decades, fall is the only period of extensive warming over the entire Antarctic Peninsula, and it is mostly from atmospheric circulation patterns originating in the tropics.

Cooling ocean temperature could buy more time for coral reefs

Tue, 14 May 2013 11:28:28 EDT

Limiting the amount of warming experienced by the world's oceans in the future could buy some time for tropical coral reefs, say researchers.

Seabird bones reveal changes in open-ocean food chain

Mon, 13 May 2013 17:43:43 EDT

Remains of endangered Hawaiian petrels -- both ancient and modern -- show how drastically today's open seas fish menu has changed. Scientists analyzed the bones of Hawaiian petrels -- birds that spend the majority of their lives foraging the open waters of the Pacific. They found that the substantial change in petrels' eating habits, eating prey that are lower rather than higher in the food chain, coincides with the growth of industrialized fishing.

Using earthquake sensors to track endangered whales

Mon, 13 May 2013 15:24:24 EDT

Oceanographers used data from seafloor seismometers to analyze more than 300,000 fin-whale calls. By triangulating the position they created more than 150 tracks off the Pacific Northwest coast.

Western Indian Ocean earthquake and tsunami hazard potential greater than previously thought

Mon, 13 May 2013 10:37:37 EDT

Earthquakes similar in magnitude to the 2004 Sumatra earthquake could occur in an area beneath the Arabian Sea at the Makran subduction zone, according to recent research.

Under-appreciated benefit of oyster restoration highlighted

Thu, 09 May 2013 15:46:46 EDT

A new study shows that healthy oyster reefs would help to buffer the increasing acidity of coastal waters.

New robotic instruments to provide real-time data on Gulf of Maine red tide

Tue, 07 May 2013 15:50:50 EDT

A new robotic sensor deployed coastal waters may transform the way red tides or harmful algal blooms are monitored and managed in New England. The instrument was launched at the end of last month, and a second such system will be deployed later this spring.