Following rapid warming in the late 20th century, this century has so far seen surprisingly little increase in the average temperature at the Earth’s surface. At first this was a blip, then a trend, then a puzzle for the climate science community. More than a dozen theories have now been proposed for the so-called global warming hiatus, ranging from air pollution to volcanoes to sunspots.
The sweet and salty aroma of sunscreen and seawater signals a relaxing trip to the shore. But scientists are now reporting that the idyllic beach vacation comes with an environmental hitch. When certain sunblock ingredients wash off skin and into the sea, they can become toxic to some of the ocean’s tiniest inhabitants, which are the main course for many other marine animals.
From research stations drifting on ice floes to high-tech aircraft radar, scientists have been tracking the depth of snow that accumulates on Arctic sea ice for almost a century. Now that people are more concerned than ever about what is happening at the poles, research led by the Univ. of Washington and NASA confirms that snow has thinned significantly in the Arctic, particularly on sea ice in western waters near Alaska.
As the climate warms and sea ice retreats, the North is changing. An ice-covered expanse now has a season of increasingly open water that is predicted to extend across the whole Arctic Ocean before the middle of this century. Storms thus have the potential to create Arctic swell. A Univ. of Washington researcher made the first study of waves in the middle of the Arctic Ocean, and detected house-sized waves during a September 2012 storm.
The U.S. Geological Survey plans this summer and next to map the outer limits of the continental shelf, and also study underwater landslides that would help predict where and when tsunamis might occur. But environmentalists say it could cause the same type of marine life damage they fought unsuccessfully to prevent this month off the coast of New Jersey.
Until now, computer simulations of habitable climates on Earth-like planets have focused on their atmospheres. Mathematicians and earth sciences experts in the U.K. have recently taken the next step, creating a computer-simulated pattern of ocean circulation on a hypothetical ocean-covered Earth-like planet. They hope to learn how different planetary rotation rates would impact heat transport with the presence of oceans taken into account.
In an attempt to prevent vast quantities of oil from fouling beaches and marshes after the 2010 Deepwater Horizon spill in the Gulf of Mexico, BP applied 1.84 million gallons of chemical dispersant. The dispersant was thought to rapidly degrade in the environment, but a new study has found that the DOSS dispersant compound remains associated with oil and can persist in the environment for up to four years.
Iron is present in tiny concentrations in seawater, on the order of a few billionths of a gram in a liter. However, its availability in seawater can have a profound effect on phytoplankton growth and, consequently, the Earth's carbon cycle. In recent research, an assessment was made of the various sources of dissolved iron in the north Atlantic Ocean and surprising discoveries were made about their origins.
Plastic junk is floating widely on the world's oceans, but there's less of it than expected, a study says. A newly published study drew on results from an around-the-world cruise by a research ship that towed a mesh net at 141 sites, as well as other studies. Researchers estimated the total amount of floating plastic debris in open ocean at 7,000 to 35,000 tons.
In the last 40 years, ice loss from the Greenland Ice Sheet increased four-fold contributing to one-quarter of global sea level rise. Some of the increased melting at the surface of the ice sheet is due to a warmer atmosphere, but the ocean’s role in driving ice loss largely remains a mystery. Research by U.S. scientists sheds new light on the connection between the ocean and Greenland’s outlet glaciers.
Researchers report evidence for an oceans worth of water deep beneath the U.S. Though not in the familiar liquid form—the ingredients for water are bound up in rock deep in the Earth’s mantle—the discovery may represent the planet’s largest water reservoir. The presence of liquid water on the surface is what makes our “blue planet” habitable, and scientists have tried to figure out just how much water may be cycling between Earth’s surface.
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.
If the wreckage of a missing Malaysian airliner rests somewhere in the Indian Ocean's depths, then investigators will likely need to entrust the hunt at least partly to robot submarines and the scientists who deploy them to scan remote swaths of the seafloor. Such unmanned subs played a critical role in locating the carcass of a lost Air France jet in 2011, two years after it crashed in the middle of the south Atlantic.
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.