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Sampling the Pacific for Signs of Fukushima

By Guest PostApril 6, 2012Environmentcesium 134, chiba peninsula, coast of japan, earthquake, fukushima, fukushima dai ichi, gulf stream, hawaii, irina rypina, Japan, ken buesseler, kuroshio, marine ecosystem, marine environment, marine organism, nicholas fisher, nuclear power plant, ocean, ocean current, oyashio, plankton, potassium 40, radiation, radioactive isotope, radioactive substance, radioactivity, radionuclides, reactor, seafloor sediment, steven jayne, tsunami, whoi

An international research team is reporting the results of a research cruise they organized to study the amount, spread, and impacts of radiation released into the ocean from the tsunami-crippled reactors in Fukushima, Japan. The group of 17 researchers and technicians from eight institutions spent 15 days at sea in June 2011 studying ocean currents, and sampling water and marine organisms up to the edge of the exclusion zone around the reactors.

Led by Ken Buesseler, a senior scientist and marine chemist at the Woods Hole Oceanographic Institution (WHOI), the team found that the concentration of several key radioactive substances, or radionuclides, were elevated but varied widely across the study area, reflecting the complex nature of the marine environment. In addition, although levels of radioactivity in marine life sampled during the cruise were well below levels of concern for humans and the organisms themselves, the researchers leave open the question of whether radioactive materials are accumulating on the seafloor sediments and, if so, whether these might pose a long-term threat to the marine ecosystem. The results appear in the April 2 online edition of the journal Proceedings of the National Academy of Sciences (PNAS). (more…)

Explosive Evolution Need Not Follow Mass Extinctions

By Guest PostFebruary 14, 2012Scienceadaptive radiation idea, canisius college, charles e mitchell, charlotte hsu, climate change, david w bapst, deforestation, diplograptines, ecological release hypothesis, ecosystem, evolutionary lag, explosive evolution, fossil record, graptoloid evolution, graptoloid history, graptoloids, h david sheets, life on earth, marine organisms, mass extinction, michael j melchin, neograptines, ordovician mass extinction, peter c bullock, physical traits, plankton, university at buffalo, university of chicago, zooplankton

In the wake of a mass extinction like the one that occurred 445 million years ago, a common assumption is that surviving species tend to proliferate quickly into new forms, having outlived many of their competitors.

But new research shows that tiny marine organisms called graptoloids did not begin to rapidly develop new physical traits until about 2 million years after competing species became extinct. (more…)

Rising Carbon Dioxide Levels at End of Last Ice Age Not Tied to Pacific Ocean, As Had Been Suspected

By Guest PostOctober 9, 2011Environmentalan mix, carbon dioxide, co2 levels, coast of southwestern oregon, continental ice sheets, david lund, deep ocean, glacial times, heat trapping greenhouse gas, irvine, john southon, last ice age, levels of atmospheric carbon dioxide, microscopic shells, oregon state university, paleoclimatologist, plankton, radiocarbon dating, reservoir of carbon during glacial times, sediment core, university of california, university of michigan, ventilation rate

ANN ARBOR, Mich.— After the last ice age peaked about 18,000 years ago, levels of atmospheric carbon dioxide rose about 30 percent. Scientists believe that the additional carbon dioxide—a heat-trapping greenhouse gas—played a key role in warming the planet and melting the continental ice sheets. They have long hypothesized that the source of the gas was the deep ocean.

But a new study by a University of Michigan paleoclimatologist and two colleagues suggests that the deep ocean was not an important source of carbon during glacial times. The finding will force researchers to reassess their ideas about the fundamental mechanisms that regulate atmospheric carbon dioxide over long time scales. (more…)

Researchers Find That Pollution Forms an Invisible Barrier for Marine Life

By Guest PostMarch 18, 2011Environmentanthropogenic factors, bacteria, chemicals, chlorinated hydrocarbons, coastal areas, coastal water ecosystems, contaminants, discharge, ecosystem based management, evolutionary trajectory, heavy metals, human impacts, human stressors, jon puritz, larvae, los angeles, marine life, municipal treatment plants, nutrients, ocean, pacific coast, petroleum hydrocarbons, plankton, pollutants, population, rob toonen, sea stars, sewage, southern california bight, species, starfish, toxic, united states, urban runoff, urban runoff plumes

Over 50 percent of the population in the United States and over 60 percent in the world live in coastal areas. Rapidly growing human populations near the ocean have massively altered coastal water ecosystems.

One of the most extensive human stressors is the discharge of chemicals and pollutants into the ocean. In the Southern California Bight, more than 60 sewage and urban runoff sources discharge over 1 billion gallons of liquid on a dry day with the two largest sources of contaminants being sewage from municipal treatment plants and urban runoff from highly modified river basins. (more…)

Researchers Find Widespread Floating Plastic Debris in the Western North Atlantic Ocean

By Guest PostAugust 21, 2010Environmentchris reddy, great pacific garbage patch, john bullard, kara lavender law, missing plastic, nikolai maximenko, oceans, pacific commonly, paul joyce, plankton, plastic debris, plastic pieces, plastic pollution, sea, sea education association, triggerfish, uh, university of hawaii, western north atlantic, whoi, woods hole oceanographic institution, world

Despite growing awareness of the problem of plastic pollution in the world’s oceans, little solid scientific information existed to illustrate the nature and scope of the issue.

This week, a team of researchers from Sea Education Association (SEA), Woods Hole Oceanographic Institution (WHOI), and the University of Hawaii (UH) published a study of plastic marine debris based on data collected over 22 years by undergraduate students in the latest issue of the journal Science.

(more…)

Tag Archives: plankton

Sampling the Pacific for Signs of Fukushima

Explosive Evolution Need Not Follow Mass Extinctions

Rising Carbon Dioxide Levels at End of Last Ice Age Not Tied to Pacific Ocean, As Had Been Suspected

Researchers Find That Pollution Forms an Invisible Barrier for Marine Life

Researchers Find Widespread Floating Plastic Debris in the Western North Atlantic Ocean