Today, marine fish are largely surveyed using selective and invasive methods mostly limited to commercial species, and restricted to areas with favorable conditions. Researchers in Denmark, however, have shown that seawater contains DNA from animals such as fish and whales. They have successfully used this trace presence, using as little as half a liter of water, to establish a method for tracking species.
Charles Darwin hypothesized in 1880 that most species could not disperse across the Eastern Pacific Barrier, an uninterrupted 4,000-mile stretch of water with depths of up to 7 miles that separates the central from the eastern Pacific Ocean. Scientists have confirmed this hypothesis for many species, but recent research by Penn State University is the first to determine its effect on coral.
If recent research by a team from the U.S. and Germany is correct, previous estimates about the total mass of all life on planet Earth will have to be reduced by about one third. The revision came about after researchers realized that previous drill cores, upon which the estimate are based, were recovered close to shore or in nutrient-rich areas. However, much of the ocean is a “desert”, supporting very little life.
The National Snow and Ice Data Center reported Monday that the extent of Arctic sea ice shrank to 1.58 million square miles and is likely to melt more in the coming weeks. That breaks the old record of 1.61 million square miles set in 2007. Data center scientist Ted Scambos said the melt can be blamed mostly on global warming from man-made emissions of greenhouse gases.
At this week’s American Chemical Society meeting, a number of scientists reported progress toward workable solutions for extracting uranium for nuclear power from seawater, which holds at least four billion tons of the material. The concept, which dates back 40 years, is seen as a crucial step for making future nuclear power operations viable.
The average temperature of oceans is rising along with the temperatures in the atmosphere, raising concern that ice-like compounds called methane hydrates could dissolve this powerful greenhouse gas into the atmosphere. An expedition to Spitsbergen in the high Arctic could help answer this question.
This week researchers have reported the first detailed data on methane-exhaling microbes that live deep in the cracks of hot undersea volcanoes. As evidence builds that a large amount of biomass exists in Earth’s subsurface, the scientists’ major goal was to test results of predictive computer models and to establish the first environmental hydrogen threshold for these extreme microbes.
The Southern Ocean is an important carbon sink. Around 40% of the annual global carbon dioxide emissions absorbed by the world’s oceans enter through this region. A team of British and Australian scientists has recently discovered how this carbon is drawn down from the surface of the Southern Ocean to the deep waters beneath.
Debate over the origin of large-scale polygons (often many kilometers in diameter) on Mars has been intensified by comparison to similar geometric patterns on Earth. Geologists at The University of Texas at Austin have recently examined these polygons and compared them to similar features on Earth's seafloor, which they believe may have formed via similar processes.
The powerful magnitude-8.6 earthquake that shook Sumatra on April 11, 2012, was a seismic standout for many reasons, not the least of which is that it was larger than scientists thought an earthquake of its type could ever be. Now, researchers from the California Institute of Technology report on their findings from the first high-resolution observations of the underwater temblor, they point out that the earthquake was also unusually complex
On Monday, the head of the National Oceanic and Atmospheric Administration said that oceans' rising acid levels have emerged as one of the biggest threats to coral reefs. Acid acts as the "osteoporosis of the sea,” he said, and threatens everything from food security to tourism to livelihoods.
In what's known as the North Atlantic Bloom, an immense number of phytoplankton burst into color, first "greening" then "whitening" the sea as one species follows another. According to recent research, whirlpools, or eddies, swirl across the surface of the North Atlantic Ocean, sustaining phytoplankton and acting as a biological pump. An important question is how this might change in the future.
New research by a team of Lawrence Livermore National Laboratory scientists and international collaborators shows that the observed ocean warming over the last 50 years is consistent with climate models only if the models include the impacts of observed increases in greenhouse gas during the 20th century.
A seaweed considered a threat to the healthy growth of coral reefs in Hawaii may possess the ability to produce substances that could one day treat human diseases, a new study led by scientists at Scripps Institution of Oceanography at University of California, San Diego has revealed.
The first global analysis of carbon stored in seagrasses has revealed a surprising figure. While a typical terrestrial forest stores about 30,000 metric tons of carbon per square kilometer, most of which is in the form of wood, coastal seagrasses can account for 83,000 metric tons of carbon per square kilometer. Their global impact is significant as well.
Starting this week, U.S. Navy divers will be part of a multinational effort near Estonia to help clear the Baltic Sea of underwater mines left over from as long ago as the First and Second World Wars. At the same time, physicians are studying these divers and how gas molecules form in humans who experience long periods deep underwater.
According to predictions made by climate researchers with the Alfred Wegener Institute for Polar and Marine Research, the Filchner-Ronne Ice Shelf fringing the Weddell Sea in Antarctica may start to melt rapidly in this century and no longer act as a barrier for ice streams draining the Antarctic Ice Sheet. They claim this finding refutes previous assumptions that climate change would not affect the Weddell Sea.
An increase in plastic debris floating in a zone between Hawaii and California is changing the environment of at least one marine critter, scientists recently reported. Over the past four decades, the amount of broken-down plastic has grown significantly in a region dubbed the "Great Pacific Garbage Patch." Most of the plastic pieces are the size of a fingernail.
Different versions of microengines have been developed, including devices that could transport medications through the bloodstream. But until now no one has ever shown that these devices—which are about 10 times smaller than the width of a human hair—could help clean up oil spills. Scientists are reporting successful testing of the first self-propelled “microsubmarines” designed to pick up droplets of oil and transport them.
Seeking out statistical techniques that had not previously been applied to finding the current rate of sea level rise and the rates of ice sheet melting, scientists in Canada have developed a new method to distinguish sea-level fingerprints. The technique relies on the fact that the historical pattern for each ice sheet is unique and is preserved.
Seismologists say last week's powerful earthquake off western Indonesia increased pressure on the source of the devastating 2004 tsunami: a fault that could unleash another monster wave sometime in the next few decades.
Researchers at the Virginia Institute of Marine Science are investigating whether sound waves can be used to determine the size of oil droplets in the subsea—knowledge that could help guide the use of chemical dispersants during the cleanup of future spills.
Research led by scientists at the American Museum of Natural History shows that ammonites—an extinct type of shelled mollusk that's closely related to modern-day nautiluses and squids—made homes in the unique environments surrounding methane seeps in the seaway that once covered America's Great Plains. These findings show that mobile shelled mollusk stayed put if conditions were right.
To the world's military leaders, the debate over climate change is long over. They are preparing for a new kind of Cold War in the Arctic, anticipating that rising temperatures there will open up a treasure trove of resources, long-dreamed-of sea lanes and a slew of potential conflicts.
A panel of experts in Japan recently said that any tsunami unleashed by a magnitude-9.0 earthquake in the Nankai trough, which runs east of Japan's main island of Honshu to the southern island of Kyushu, could top 34 m (112 ft) at its highest. This is a significant elevation of risk from an earlier forecast in 2003 that put the potential maximum height of such a tsunami at less than 20 m.