Tag Archives: ocean

Thawing Permafrost 50 Million Years Ago Led To Warm Global Events, Says New Study

By Guest PostApril 7, 2012EnvironmentAntarctica, arctic permafrost, carbon, climate, climatic threshold, CO2, earth, eccentric orbits, ecosystem, Environment, floor sediment, fossil fuel, frozen-soil, greenhouse gas levels, italy, kevin schaefer, methane gas, ocean, orbit, organic matter, paleocene eocene, permafrost, permafrost thaw, petm, rob deconto, soil, source, thermal maximum, university of urbino

A new study led by the University of Massachusetts Amherst and involving the University of Colorado Boulder proposes a simple new mechanism to explain the source of carbon that fed a series of extreme warming events on Earth about 50 million years ago called the Paleocene-Eocene Thermal Maximum, or PETM, as well as a sequence of similar, smaller warming events afterward.

“The standard hypothesis has been that the source of carbon was in the ocean in the form of frozen methane gas in ocean-floor sediments,” said lead study author Rob DeConto of the University of Massachusetts Amherst. “We are instead ascribing the carbon source to the continents in polar latitudes where permafrost can store massive amounts of carbon that can be released as CO2 when the permafrost thaws.” (more…)

Gulf of Mexico Oil Spill’s Effects on Deep-Water Corals

By Guest PostMarch 27, 2012Environmentalvin, charles fisher, christopher german, corals, deep sea, deep water coral, deepwater horizon, ecosystem, erik cordes, gas chromatography, gulf of mexico, haverford college, helen white, jason, macondo spill, national science foundation, ocean, oil, oil spill, pen yuan hsing, penn state university, Pennsylvania, petroleum analysis, petroleum hydrocarbon, psu, rapid grant, rodey batiza, rov, submarine, temple university, timothy shank, two dimensional, U.S. Geological Survey, whoi

*Damaged deep-sea corals discovered months after Deepwater Horizon spill*

Scientists are reporting new evidence that the Deepwater Horizon oil spill has affected marine life in the Gulf of Mexico, this time species that live in dark ocean depths–deepwater corals.

The research used a range of underwater vehicles, including the submarine Alvin, to investigate the corals. The findings are published this week in the journal Proceedings of the National Academy of Sciences (PNAS). (more…)

Wind Energy

By Guest PostMarch 22, 2012Environmentalison bates, ccp, coast, delaware, environmental impact, human activity, jeremy firestone, kateryna samoteskul, marine ecosystem, marine mammal, maryland, nature conservation, new jersey, ocean, offshore wind farms, sea turtle migrations, spatial planning, teresa messmore, university of delaware

UD study assesses ocean use off Delaware, Maryland and New Jersey coasts

The Center for Carbon-Free Power Integration (CCPI) at the University of Delaware has issued a new report about ocean use off the coast of Delaware and parts of Maryland and New Jersey. The study addresses viable places to locate offshore wind farms, taking into account biological, ecological and other considerations. The report includes feedback from interested groups who attended a November 2011 workshop, as well as input from experts.

“This report demonstrates that the ocean is already active with ecological and human activity,” lead-author Alison Bates said. “It shows what government regulators ought to consider in planning for offshore wind development and the beginning of a way forward for offshore wind developers and existing users to accommodate one another.” (more…)

Study Links Past Changes in Monsoon to Major Shifts in Indian Civilizations

By Guest PostMarch 15, 2012Environmentasia, band of heavy rain, bay of bengal, camilo ponton, civilizations, climate change, cmz, core monsoon zone, dorian fuller, drilling vessel, drought, equator, eth, global warming, godavari river, harappan civilization, humid monsoon, India, indian monsoon, indian peninsula, insolation, inter tropical convergence zone, itcz, joides resolution, liviu giosan, modern agriculture, monsoon, northern hemisphere, ocean, paleo climatic information, plankton fossil, sahara desert, sediment core, solar radiation, tim eglinton, tropical forest, vegetation, whoi, zurich

A fundamental shift in the Indian monsoon has occurred over the last few millennia, from a steady humid monsoon that favored lush vegetation to extended periods of drought, reports a new study led by researchers at the Woods Hole Oceanographic Institution (WHOI). The study has implications for our understanding of the monsoon’s response to climate change.

The Indian peninsula sustains over a billion people, yet it lies at the same latitude as the Sahara Desert. Without a monsoon, most of India would be dry and uninhabitable. The ability to predict the timing and amount of the next year’s monsoon is vital, yet even our knowledge of the monsoon’s past variability remains incomplete. (more…)

Evolution of Earliest Horses Driven by Climate Change

By Guest PostFebruary 24, 2012Environment, Nature, Scienceaaron wood, atmosphere, bighorn basin, body size, cabin fork area, carbon, carbon dioxide, cause and effect, climate model, clydesdale, concentration, doug boyer, dwarfing phenomenon, earliest horse, evolution, florida museum of natural history, fossil, geochemical analysis, global temperature, h richard lane, horse teeth, industrial revolution, jonathan bloch, mammal, national science foundation, natural selection, North America, nsf, ocean, ornithologist, oxygen levels, paleocene-eocene thermal maximum, petm, prediction, ross secord, sifrhippus sandae, stephen chester, temperature, university of florida, university of nebraska lincoln, worland, yale

*The hotter it gets, the smaller the animal?*

When Sifrhippus sandae, the earliest known horse, first appeared in the forests of North America more than 50 million years ago, it would not have been mistaken for a Clydesdale.

It weighed in at around 12 pounds–and it was destined to get much smaller over the ensuing millennia.

Sifrhippus lived during the Paleocene-Eocene Thermal Maximum (PETM), a 175,000-year interval of time some 56 million years ago in which average global temperatures rose by about 10 degrees Fahrenheit. (more…)

Global Extinction: Gradual Doom as Bad as Abrupt

By Guest PostFebruary 8, 2012Environment, Sciencebrooks ellwood, canadian arctic, carbon dioxide, charles henderson, coal deposit, dead zone, earth, ellesmere island, extinction, factor, fossil, geologic history, geology, global extinction, greenhouse, greenhouse gas, h richard lane, harry rowe, indian ocean, katherine freeman, marine life, mass extinction, national science foundation, ocean, permian period, permian triassic boundary, sedimentary rock, siberian traps, siberian volcanic activity, south china, steven bates, tethys, the great dying, thomas algeo, timothy lyons, united states, university of calgary, university of cincinnati, volcanic deposit, volcanic rock, volcanism in siberia, warming, west blind fiord

*In “The Great Dying” 250 million years ago, the end came slowly*

The deadliest mass extinction of all took a long time to kill 90 percent of Earth’s marine life–and it killed in stages–according to a newly published report.

It shows that mass extinctions need not be sudden events.

Thomas Algeo, a geologist at the University of Cincinnati, and 13 colleagues have produced a high-resolution look at the geology of a Permian-Triassic boundary section on Ellesmere Island in the Canadian Arctic. (more…)

First Plants Caused Ice Ages

By Guest PostFebruary 1, 2012Environment, Natureatmospheric carbon, atmospheric carbon level, calcium, carbon cycle, carbonate rocks, chemical weathering, climate, earth surface, first land plants, global cooling, granite, ice ages, iron, liam dolan, magnesium, marine life, mass extinction, mineral, modern moss, ocean, ordovician period, oxford university, phosphorus, physcomitrella patens, reduction, rocks, silicate rocks, tim lenton, university of exeter

*New research reveals how the arrival of the first plants 470 million years ago triggered a series of ice ages. Led by the Universities of Exeter and Oxford, the study is published in Nature Geoscience.*

The team set out to identify the effects that the first land plants had on the climate during the Ordovician Period, which ended 444 million years ago. During this period the climate gradually cooled, leading to a series of ‘ice ages’. This global cooling was caused by a dramatic reduction in atmospheric carbon, which this research now suggests was triggered by the arrival of plants.

Among the first plants to grow on land were the ancestors of mosses that grow today. This study shows that they extracted minerals such as calcium, magnesium, phosphorus and iron from rocks in order to grow. In so doing, they caused chemical weathering of the Earth’s surface. This had a dramatic impact on the global carbon cycle and subsequently on the climate. It could also have led to a mass extinction of marine life. (more…)

New CU-led Study May Answer Long-Standing Questions About Enigmatic Little Ice Age

By Guest PostJanuary 30, 2012Environmentalps, Arctic sea ice, baffin island, bette otto bliesner, canadian arctic, China, climate feedback system, climate model, cooling effect, darren larsen, dead plant material, european glacier, feedback, gifford miller, greenland, ice, ice cap, kurt refsnider, langjökull ice cap, little ice age, london, melting icecaps, middle age, Netherlands, north atlantic ocean, norway, ocean, sea, sediment core, simulation, solar radiation, south america, thames river, tropical volcanic eruptions, volcanic aerosols, waterways, yafang zhong

A new University of Colorado Boulder-led study appears to answer contentious questions about the onset and cause of Earth’s Little Ice Age, a period of cooling temperatures that began after the Middle Ages and lasted into the late 19th century.

According to the new study, the Little Ice Age began abruptly between A.D. 1275 and 1300, triggered by repeated, explosive volcanism and sustained by a self- perpetuating sea ice-ocean feedback system in the North Atlantic Ocean, according to CU-Boulder Professor Gifford Miller, who led the study. The primary evidence comes from radiocarbon dates from dead vegetation emerging from rapidly melting icecaps on Baffin Island in the Canadian Arctic, combined with ice and sediment core data from the poles and Iceland and from sea ice climate model simulations, said Miller. (more…)