Courtesy David Sandwell, Scripps Institution of Oceanography, UC San DiegoResearchers at the Scripps Institution of Oceanography at UC San Diego have used archived satellite data to develop new, detailed maps of the ocean floor, giving scientists new insights into earthquakes, spreading seafloors, and plate tectonics. The maps are the latest to be compiled in over two decades and provide a higher resolution picture of the ocean bottom revealing features not seen in previous versions. The study appears in the journal Science.
Courtesy Patricia L. CorcoranGeologists have always considered rocks to be plastic because they are often reformed, remelted, and reshaped by tectonic forces such as heat and pressure. But now, earth scientists have declared a new type of rock they're calling plastiglomerates. It's a composition of volcanic rock and actual plastic, or a clump of rock, sand, coral and seashells all held together by a mass of melted plastic derived from human debris.
Considering we humans have been generating heaps of plastic waste since the middle of the last century (and enough to wrap up our entire planet in plastic) it's no wonder some of it has managed to find its way into the rock cycle. It's only surprising that it took us this long to notice it.
Chunks of plastiglomerate were found recently at a beach in Hawaii. Patricia Corcoran, a geologist from the University of Western Ontario, and Charles Moore, captain of the research vessel Alguita discovered plastiglomerates at 21 different sites they surveyed on Kamilo Beach located on the southern tip of the Big Island of Hawaii. Their study appears in the latest issue of GSA Today.
Courtesy NASAKamilo Beach is an isolated location that, due to ocean currents and trade winds, and its location, has long been a magnet for plastic and other trash floating on the Pacific. In the distant past, native Hawaiians collected wood from Kamilo that had floated in from the Pacific Northwest to make dugout canoes. There's no easy access to the beach - it's usually void of beach-goers and takes a two hour four-wheel drive over a jagged lava field just to reach it. But each year, 15 to 20 tons of all sorts of floating plastic - from toothbrushes to water bottles to toy green army men - pile up on the rocks and sand of Kamilo. It's not the only place of course, plastic debris has been found in different areas of ocean bottom around the world. It's not surprising that some of it ends up joined with other elements to form the new rock.
Plastiglomerates are thought to have formed probably from plastic melted in beach campfires or in lava flows, which aren't unusual on the Big Island. In the distant future, as plastic gets further buried under layers of future sedimentation or lava flows, it will likely become even more incorporated, melting and re-melting under extreme heat or pressure and filling in cracks and crevasses in the country rock much like minerals such as quartz and pyrite have done in the past. Tens or hundreds of thousands of years from now, future geologists will no doubt be able to use these traces as markers for the Anthropocene era, the name gradually gaining acceptance to describe humanity's post-agricultural or industrial time on the planet.
This is something you don't see everyday: a plethora of life existing in a single drop of seawater, magnified 25 times, and captured by photographer David Littschwager. Another reason not to swallow the ocean.
Curious of what sort of creatures appear in the photo? Go here for an explanation.
Courtesy Mark RyanOver the past couple years, Science Buzz has posted several stories (here and here) about the humongous patches of garbage and plastic debris found floating in the world's oceans. It's a serious problem and one that should raise red flags for anyone concerned with the Earth's environment. But even more troubling is the recent news that plastic particles have now been found in all five of the Great Lakes lining the border of the USA and Canada. Unlike the large globs of plastic clogging areas of the ocean, the plastics polluting the Great Lakes are microscopic particles detectable only in a microscope. But they're no less disturbing.
A team of researchers led by Dr. Sherri “Sam” Mason, professor of chemistry at SUNY-Fredonia has been gathering water samples and reported finding high concentrations of plastic particles in the chain of freshwater lakes. One of the researchers involved is environmental chemist Lorena Rios-Mendoza from University of Wisconsin-Superior. Both she and Mason have studied the Great Trash Island (aka Trashlantis) in the Pacific Ocean but has now turned their attention to the Great Lakes.
Most of the plastic found in the water is visible only under a microscope, but has been found in all five of the Great Lakes, both in the water column, and in lake sediment. The amount of micro-plastic varies between lakes with Lake Erie - the shallowest and smallest by water volume - containing the largest ratio and Lake Superior - the largest and most voluminous - a much smaller ratio. But it doesn't matter; the point is that we're polluting some of our important sources of fresh water with plastic.
It's thought that cosmetics with could one of the sources, since the industry relies heavily on using micro-beads in its products. These tiny plastic particles used on our faces, skin, and teeth, eventually get washed off into the water supply where they're too small to get filtered out. But cosmetics certainly aren't the only source.
Courtesy tedxgp2Think of the ungodly amount of plastic material we use and discard every year. Surprisingly, only about five percent of the bags, bottles, cups, electronics, etc. get recycled; most plastic trash ends up in landfills where it slowly degrades and eventually finds its way into the world's favorite garbage dump: the oceans.
“We have no idea how long some of these plastics stay in the ocean, could be more than 40 years,” Rios-Mendoza said. She also worries if organic toxins in the water can attach themselves to the tiny plastic particles, and end up in the food chain. In this regard, Rios-Mendoza has been sampling Great Lake fish to see if such toxic particles are present in their guts.
It's important to remember that only 3 percent of the world's water is freshwater and the five Great Lakes - Superior, Huron, Michigan, Ontario, and Erie - together contain 20 percent of that freshwater. That's a large portion of a relatively scarce and essential life ingredient. Last fall, I posted an interesting graphic that illustrates nicely Earth's total water supply versus fresh water and puts things in perspective.
Courtesy Mark RyanRios-Mendoza and Mason have been collaborating with a research and education group called 5Gyres Institute that monitors and studies garbage patches found in five subtropical gyres in the world's oceans. Rio-Mendoza presented a preliminary study of their work on the Great Lakes at a recent meeting of the American Chemical Society. The team's future studies involve pinpointing the sources of plastic pollution and acquiring a better understanding of how plastics degrade in the environment.
"We all need to become aware of how much plastic we use in our lives and avoid using single-use products. Don’t buy water in plastic bottles or cosmetic products with micro beads. Bring re-usable bags to the store with you. Simple things like this make a big difference, but it’s also important to keep talking about this issue and raising awareness about how it affects the Great Lakes and the world’s oceans.” --- Dr. Sherri Mason“
By the way, here in Minnesota, and situated at the western tip of Lake Superior, the city of Duluth was recently proclaimed to have the best tasting drinking water in the state. By best-tasting, I'm assuming they mean it has no taste whatsoever since water is described as a colorless, tasteless liquid. Whatever the case, I always thought Duluth's drinking water was the best while growing up there (my grandparents lived in a Twin Cities' suburb and I never liked the taste of their softener-treated water).
In another water-related story, it's estimated that life on Earth can survive for at least another 1.75 billion years until we move out of the habitable zone and our oceans (and other water sources) will evaporate in the increased heat. So it's probably best that we take care of what water we have - it needs to sustain us for a long time.
Courtesy EMSLMicrobes found living in rocks 1.5 miles under the ocean floor live such slow-paced lives that they reproduce only every 10,000 years or so. That's a long time between generations. They live this way in rocks estimated to be 100 million years old. The discovery was announced by scientists from the Integrated Ocean Drilling Program at a meeting of geochemists at the Goldschmidt onference in Florence, Italy. Scientists have also discovered other life forms - viruses and fungi - living zombie-like existences in the same deep rock layers.
Dr Beth Orcutt of Bigelow Laboratory for Ocean Sciences in Maine wonders how life exists in such extreme environments and where Earth's biosphere actually terminates.
"The deeper we look, the deeper we are still finding cells," she said, "and the discussion now is where is the limit? Is it going to be depth, is it going to be temperature? Where is the limit from there being life to there being no life?"
The density of the microbial population living in the deep rocks is miniscule compared to those found at the surface, but scientists still wonder if the microbes can actually be changing the lithosphere through chemical reaction with carbon and other elements in the rocks, and what results from that interaction.
Want to see how the Titanic's final resting place at the bottom of the Atlantic Ocean compares to that of the Edmund Fitzgerald in Lake Superior? Or get a real sense of just how deep Titanic film director James Cameron dove recently into the Challenger Deep section of the Marianas Trench? These questions I'm sure have been on everybody's minds because this coming weekend marks the 100th Anniversary of the Titanic's fateful night. Well, maybe some of you haven't been thinking about it, but for those who have, it's all here in a really nifty chart on the XKCD.com website. It's actually kind of interesting. You should note that only the depths in the chart are to scale, the lateral distances are not. It gives you a good appreciation of Cameron's recent diving feat or possibly the level of his insane nature. Wow!
Courtesy University of MiamiSecond-grader Sophi Bromenshenkel from Minnesota sold lemonade, hot chocolate, shark-shaped cookies, and wristbands to promote shark conservation, and become an international phenomenon. Earlier this year, 8-year old Sophi was named the 2011 "Ocean Hero" from Oceana, an international advocacy group working to protect the world’s oceans. She graces the front cover of the latest issue of Oceana Magazine.
Through her efforts, $3,676.62 was raised to pay for satellite tags that are used to track movement of individual sharks, and provide insight on shark populations. In addition to providing safety information to recreational ocean users, the observations of how sharks navigate the ocean can be used to inform policymakers where to focus their marine protection efforts. The satellite-tagged sharks can be followed online from the website for the R.J. Dunlap Marine Conservation Program. Note that the Google Earth Plugin needs to be installed on your computer to view the maps.
Courtesy WHOIBeing on a ship exploring the oceans: how cool is that?! If you can't be on the ship, or maybe you get seasick and don't want to be, check out videos from a real oceanography expedition.
An entire series is now on Science 360: The Knowledge Network. YouTube videos are filtered from some classrooms. Since Science 360 is sponsored by the National Science Foundation, their videos have passed a high academic standard and are not filtered.
Courtesy C-MOREThe Center for Microbial Oceanography (C-MORE), headquartered at the University of Hawai`i, conducted the BiG RAPA oceanographic expedition. The C-MORE scientists sailed from Chile to Easter Island, making discoveries about micro-life in one of the least explored areas of the world's ocean.
Courtesy C-MOREHow would you like to be aboard a ship, circumnavigating the globe, collecting samples from the world’s ocean?
That’s exactly what Spanish oceanographers are doing on their Malaspina Expedition aboard the Research Vessel, R/V Hespérides. Scientists and crew left southern Spain in December, reached New Zealand in mid-April, and recently arrived in Hawai`i. The expedition's primary goals are to:
Courtesy C-MOREIn connection with the latter two goals, the Malaspina scientists met with their colleagues at the Center for Microbial Oceanography: Research and Education (C-MORE). The two groups of scientists are working together. "We can exchange data on the local effects, what's happening around the Hawaiian Islands, and they can tell us what's happening in the middle of the Pacific," said Dr. Dave Karl, University of Hawai`i oceanography professor and Director of C-MORE.
The Malaspina-C-MORE partnership is the kind of cooperation that can help solve environmental problems which stretch beyond an individual nation’s borders. The R/V Hespérides has now left Honolulu on its way to Panama and Colombia. From there, the scientists expect to complete their ocean sampling through the Atlantic Ocean and return to Spain by July. Buen viaje!
Courtesy NOAAWe often talk about the ocean ecosystem. And, indeed, there is really just one, world-wide ocean, since all oceans are connected. An Indian Ocean earthquake sends tsunami waves to distant coasts. Whitecaps look as white anywhere in the world. The ocean swirls in similar patterns.
However, oceanographers do find differences from place to place. For example, let’s take a closer look at the chemistry of two swirls, or gyres as they’re more properly called. Scientists have found a micro difference between the North Atlantic Gyre and the North Pacific Gyre. The Atlantic generally has really low levels of phosphorus, measurably lower than the North Pacific Gyre.
Courtesy modified from WikipediaPhosphorus is a very important element in living things. For example, it’s a necessary ingredient in ATP (adenosine tri-phosphate), the energy molecule used by all forms of life. Phosphorus is picked up from seawater by bacteria. All other marine life depends upon these bacteria, either directly or indirectly, for P. Therefore, if you’re bacteria living in the impoverished North Atlantic Gyre, you’d better be really good at getting phosphorus.
And they are!
Oceanographers at the Center for Microbial Oceanography: Research and Education (C-MORE) at the University of Hawai`i have made an important discovery. C-MORE scientists Sallie Chisholm, based at the Massachusetts Institute of Technology and her former graduate student Maureen Coleman, now a scientist at the California Institute of Technology, have been studying two species of oceanic bacteria. Prochlorococcus is an autotrophic bacterium that photosynthesizes its own food; Pelagibacter, is a heterotrophic bacterium that consumes food molecules made by others.
Courtesy C-MOREDrs. Chisholm and Coleman took samples of these two kinds of bacteria from both the Atlantic and Pacific Ocean. The Atlantic samples were collected by the Bermuda Atlantic Time-Series (BATS) program. The Pacific samples were collected in the North Pacific Gyre (about 90 miles north of Honolulu) by the Hawai`i Ocean Time-Series (HOT) program. The scientists discovered surprising differences in the genetic code of the bacteria between the two locations:
Drs. Chisholm and Coleman have discovered important micro differences between bacteria of the same species in two oceanic gyres. Now we can better understand how these microbes are working to recycle an important nutrient beneath the whitecaps.