Late Ordovician mass extinction caused by tropical cooling and habitat loss

The second-largest mass extinction in Earth’s history coincided with a short but intense ice age during which enormous glaciers grew and sea levels dropped. Although it has long been agreed that the so-called Late Ordovician mass extinction — which occurred about 450 million years ago — was related to climate change, exactly how the climate change produced the extinction has not been known. Now, a team led by scientists at the California Institute of Technology (Caltech) has created a framework for weighing the factors that might have led to mass extinction and has used that framework to determine that the majority of extinctions were caused by habitat loss due to falling sea levels and cooling of the tropical oceans.

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How buying dirty fossil fuels can benefit the climate: it’s all about economics

Environmental policy has historically been driven by a demand-side mindset — attempting to limit consumption of precious fossil fuels through pollution permits, taxation, and multi-national climate change treaties. However, new research from the Kellogg School of Management at Northwestern University suggests that actually buying coal, oil and other dirty fossil fuel deposits still in the ground could be a far better way to fight climate change.

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Oyster larvae fail to survive ocean acidification

Researchers at Oregon State University have definitively linked an increase in ocean acidification to the collapse of oyster seed production at a commercial oyster hatchery in Oregon, where larval growth had declined to a level considered by the owners to be “non-economically viable.”

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Tiny air samplers new tool in improving climate models

Miniscule air samplersAn air sampler the size of an ear plug is expected to cheaply and easily collect atmospheric samples to improve computer climate models.

“We now have an inexpensive tool for collecting pristine vapor samples in the field,” said Sandia National Laboratories researcher Ron Manginell, lead author of the cover story for the Review of Scientific Instruments, the often-cited journal of the American Institute of Physics.

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Nano-copper and nano-gold combine to form effective CO2 converter

nanoparticles

Researchers have combined gold nanoparticles (in light red) with copper nanoparticles (in light green) to form hybrid nanoparticles (dark red), which they turned into powder (foreground) to catalyze carbon dioxide reduction (credit Zhichuan Xu)

Copper — the stuff of pennies and tea kettles — is also one of the few metals that can turn carbon dioxide into hydrocarbon fuels with relatively little energy. When fashioned into an electrode and stimulated with voltage, copper acts as a strong catalyst, setting off an electrochemical reaction with carbon dioxide that reduces the greenhouse gas to methane or methanol.

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30 years of ecological research shows causes and consequences of climate change

As global temperatures rise, the most threatened ecosystems are those that depend on a season of snow and ice, scientists from the nation’s Long Term Ecological Research (LTER) Network say.”The vulnerability of cool, wet areas to climate change is striking,” says Julia Jones, a lead author in a special issue of the journal BioScience released today featuring results from more than 30 years of LTER, a program of the National Science Foundation (NSF).

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Paleocene-Eocene Thermal Maximum caused by thawing permafrost?

In a new study reported in Nature, climate scientist Rob DeConto of the University of Massachusetts Amherst and colleagues elsewhere propose a simple new mechanism to explain the source of carbon that fed a series of extreme warming events about 55 million years ago, the Paleocene-Eocene Thermal Maximum (PETM), and a sequence of similar, smaller warming events afterward.

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Amount of deep cold Antarctic bottom water decreasing over last decades

Antarctic bottom water

A layer of Antarctic Bottom Water colder than 0ºC (Credit: NOAA)

Scientists have found a large reduction in the amount of the coldest deep ocean water, called Antarctic Bottom Water, all around the Southern Ocean using data collected from 1980 to 2011.

These findings, in a study now online, will likely stimulate new research on the causes of this change.

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New NRC report on the state of the polar regions

GlacierThe U.S. National Research Council has just released a synthesis of reports from thousands of scientists in 60 countries who took part in the International Polar Year (IPY) 2007-08, the first in over 50 years to offer a benchmark for environmental conditions and new discoveries in the polar regions.

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