Years after the 2010 Deepwater Horizon Oil spill, oil continues to wash ashore as oil-soaked “sand patties,” persists in salt marshes abutting the Gulf of Mexico, and questions remain about how much oil has been deposited on the seafloor. Scientists have developed a unique way to fingerprint oil, even after most of it has degraded, and to assess how it changes over time.
The paleoclimate record for the last ice age tells of a cold Earth whose northern continents were covered by vast ice sheets. Chemical traces from plankton fossils in deep-sea sediments reveal rearranged ocean water masses, as well as extended sea ice coverage off Antarctica. Air bubbles in ice cores show that carbon dioxide in the atmosphere was far below levels seen before the Industrial Revolution.
In June, 2010, two months after the Deepwater Horizon oil spill, Regina Lamendella collected samples along a hard-hit beach near Grand Isle, Louisiana. She was part of a team of Lawrence Berkeley National Laboratory researchers that wanted to know how the microbes along the shoreline were responding to the spill.
Microbiologists have recently studied unseen armies of viruses and bacteria as they wage war at hydrothermal vents more than a mile beneath the ocean's surface. They have found that viruses infect bacterial cells to obtain tiny globules of elemental sulfur stored inside the bacterial cells. Instead of stealing this bounty, the viruses force the bacteria to burn their valuable sulfur reserves, then use the unleashed energy to replicate.
The smallest, most abundant marine microbe, Prochlorococcus, is a photosynthetic bacteria species essential to the marine ecosystem. An estimated billion upon billion of the single-cell creatures live in the oceans, forming the base of the marine food chain and occupying a range of ecological niches based on temperature, light and chemical preferences, and interactions with other species.
It’s broadly understood that the world’s oceans play a crucial role in the global-scale cycling and exchange of carbon between Earth’s ecosystems and atmosphere. Now scientists at Scripps Institution of Oceanography have taken a leap forward in understanding the microscopic underpinnings of these processes. The discovery involves “recycling” bacteria that play an important role in regulating the ocean’s storage of carbon dioxide.
Fish living on coral reefs where carbon dioxide seeps from the ocean floor were less able to detect predator odor than fish from normal coral reefs, according to a new study. The study confirms laboratory experiments showing that the behavior of reef fishes can be seriously affected by increased carbon dioxide concentrations in the ocean.
Far beneath the surface of the ocean, deep currents act as conveyer belts, channeling heat, carbon, oxygen and nutrients around the globe. A new study by the Univ. of Pennsylvania’s Irina Marinov and Raffaele Bernardello and colleagues from McGill Univ. has found that recent climate change may be acting to slow down one of these conveyer belts, with potentially serious consequences for the future of the planet’s climate.
According to new research, the ice-free season across the Arctic is getting longer by five days per decade. New analysis of satellite data shows the Arctic Ocean absorbing ever more of the sun’s energy in summer, leading to an ever later appearance of sea ice in the autumn. In some regions, autumn freeze-up is occurring up to 11 days per decade later than it used to.
Twenty-five years after the infamous Exxon Valdez oil spill in Prince William Sound, beaches on the Alaska Peninsula hundreds of kilometers from the incident still harbor small hidden pockets of surprisingly unchanged oil, according to new research being presented at the American Geophysical Union meeting in Hawaii this week.
It has long been known that free, ionic silver particles can be highly toxic to aquatic organisms. Yet we a lack of detailed knowledge about the doses required to trigger a response and how the organisms deal with the stress. To learn more about the cellular processes, scientists in Switzerland subjected algae to a range of silver concentrations. The results are reassuring, but the presence of other stressors could compound the problem.
For four decades, polychlorinated biphenyls (PCBs) and heavy metals from nearby manufacturing plants flowed into New Bedford Harbor, creating one of the EPA’s largest Superfund cleanup sites. It’s also the site of an evolutionary puzzle: small Atlantic killifish are not only tolerating the toxic conditions in the harbor, they seem to be thriving there. In a new paper, researchers may have an explanation for their genetic resistance to PCBs.
A team of researchers led by Virginia Tech and Univ. of California, Berkeley, scientists has discovered that a regulatory process that turns on photosynthesis in plants at daybreak likely developed on Earth in ancient, methane-producing microbes 2.5 billion years ago, long before oxygen became available. The research opens new scientific areas in the fields of evolutionary biology and microbiology.
After a three-year overhaul and major upgrade, the United States' deepest-diving research submersible, Alvin, has been cleared to return to work exploring the ocean's depths. The sub has been out of service since December 2010, undergoing a major upgrade, including the replacement of its personnel sphere with a newly fabricated, larger, more capable hull.
Scientists at the Univ. of Liverpool have shown that deep sea fault zones could transport much larger amounts of water from the Earth’s oceans to the upper mantle than previously thought. They have estimated that over the age of the Earth, the Japan subduction zone alone could transport the equivalent of up to three and a half times the water of all the Earth’s oceans to its mantle.
Although few people live in the Western tropical Pacific Ocean region, the remote waters there affect billions of people by shaping climate and air chemistry worldwide. Next week, scientists will head to the region to better understand its influence on the atmosphere—including how that influence may change in coming decades if storms over the Pacific become more powerful with rising global temperatures.
Their effect on the surface of the ocean is negligible, producing a rise of just inches that is virtually imperceptible on a turbulent sea. But internal waves, which are hidden entirely within the ocean, can tower hundreds of feet, with profound effects on the Earth’s climate and on ocean ecosystems.
A cave discovered near the source of Indonesia's massive earthquake-spawned tsunami contains the footprints of past gigantic waves dating up to 7,500 years ago, a rare natural record that suggests the next disaster could be centuries away, or perhaps only decades. The findings provide the longest and most detailed timeline for tsunamis that have occurred off the far western tip of Sumatra island, where deadly 100-ft waves struck in 2004.
Using a new isotope technique and deep sea corals gathered near the Hawaiian Islands, a Lawrence Livermore National Laboratory scientist, in collaboration with Univ. of California Santa Cruz colleagues, has determined that a long-term shift in nitrogen content in the Pacific Ocean has occurred as a result of climate change. This shift is similar to major paleoceanographic transitions in the sedimentary record.
The U.S. Navy plans to increase sonar testing over the next five years, even as research it funded reveals worrying signs that the loud underwater noise could disturb whales and dolphins. Two recent studies off the Southern California coast found certain endangered whales stopped feeding and fled from recordings of sounds similar to military sonar. This was surprising because scientists thought they were immune to the high-pitched sounds.
Coral reefs, the most biodiverse ecosystems in the world’s oceans, provide safe harbor for fish and organisms of many sizes that make homes among the branches, nooks and crannies of the tree-like coral. But reefs are declining because of disease and bleaching, conditions exacerbated by rising ocean temperatures.
Jupiter’s moon Europa features an intricate network of cracks in its icy surface. This unusual pattern is particularly pronounced around the equator. Scientists performing modeling studies on the potential marine currents below this ice layer have discovered that, near Europa’s equator, warmer water rises from deep within the moon.
At high pressures and low temperatures, such as those in the deep oceans, carbon dioxide occurs as a liquid that is denser than seawater. Researchers in England have identified regions beneath the oceans where the igneous rocks of the upper ocean crust could safely store very large volumes of carbon dioxide.
Methane hydrates are a potential energy source, but they are also a potential source of global warming. A pair of cooperating microbes on the ocean floor "eats" this methane in a unique way, and a new study provides insights into their surprising nutritional requirements. Learning how these methane-munching organisms exist in extreme environments could provide clues about how the deep-sea environment might change in a warming world.
Researchers using transmission electron microscopy have examined the smallest building block of coral that can be identified: sphemlites. These studies have revealed three distinct regions whose formation could be directly correlated to the time of day. These findings could help scientists and environmentalists working to protect and conserve coral from the threats of acidification and rising water temperatures.