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geology

Supernova explosion detected in Early Pleistocene sediments

When a massive star comes to the end of its life cycle, it goes out with a spectacular bang known as a supernova. Only three of these events have been observed in the Milky Way in the past 1,000 years. Evidence for older explosions can be detected in the form of rare elements found on Earth that are only produced by such explosions.

10 Jan 2017

Earth's largest jet stream unexpectedly disrupted

In early 2016, scientists first noticed an unexpected change in wind direction in the stratosphere some 25 kilometers above the equator. This shift signaled the beginning of a multimonth disruption of one of the most regular atmospheric phenomena known — the quasi-biennial oscillation (QBO). The disruption is the first such event observed in this system since record keeping began in the 1950s.

06 Jan 2017

Down to Earth With: Paleoclimatologist Raymond S. Bradley

When 21-year-old Raymond S. Bradley left England in 1969 to pursue a graduate degree at the University of Colorado Boulder (CU), he thought he’d be studying Denver’s urban climate. But on arrival, a funding mix-up delayed the work and Bradley found himself in search of a new project. While his doctoral work would ultimately involve studying the precipitation history of the Rockies, a new opportunity came his way in the summer of 1970 when his officemate needed a field assistant for a trip to the Arctic. So, Bradley headed to Baffin Island in the Canadian Arctic on a three-month excursion that would prove to be just the first of dozens of Arctic expeditions to come over the course of a distinguished career.

04 Jan 2017

Current marine extinction unprecedented

In today’s ocean, larger-bodied animals are more likely to become extinct than smaller creatures, according to a new study in Science. This is contrary to extinction patterns seen during other mass extinction events in Earth’s history, during which smaller species were hit the hardest.

03 Jan 2017

Geologic Column: New Year's as we know it is new

Although commemorating the start of a new year and looking back on the past year is one of humanity’s oldest traditions, celebrating it on Jan. 1 is a relatively recent occurrence.  
 

 

31 Dec 2016

Ant bodies shaped by environment

Ants are ectotherms, which means their metabolisms are controlled by the temperature of their environment. New research shows that the environment also influences their color and size.

30 Dec 2016

Slow-moving slides may be triggered by cold temperatures

Landslides aren’t always fast-moving disasters. Slow landslides creep downhill at rates up to a few meters a year, which might not sound dramatic, but slow slides can still damage roads, pipelines and communities. Slow-moving slides are most commonly triggered by increased pore pressure in the soils due to rainfall or snowmelt, but in some places, according to a new study, temperature may also play a role. The new study looking at slow slides in Japan found that cold underground temperatures — independent of increased rainfall — may lubricate slow-moving slides.

27 Dec 2016

Panama's isthmus stays 3 million years young: Further evidence needed to support an older age

The formation of the tiny Isthmus of Panama had major geographic repercussions, cutting off the Caribbean Sea from the Pacific Ocean and connecting North and South America. A new study using multiple lines of geological, biological and molecular evidence supports the most commonly accepted age of the isthmus, about 3 million years, refuting a pair of 2015 studies that placed the closing at a much earlier date.

27 Dec 2016

Green corridors led humans out of Africa

A trail of fossil, archaeological and genetic clues suggests that modern humans, who first evolved in East Africa about 200,000 years ago, may have made forays outside Africa via the eastern Mediterranean and the Arabian Peninsula as early as 120,000 years ago. But most fossil and archaeological evidence suggests they didn’t begin widely populating the rest of the world until about 60,000 years ago.

26 Dec 2016

Mysterious Antarctic algae blown in by high winds

When fossils of microscopic marine algae called diatoms were discovered high in the Transantarctic Mountains 30 years ago, the mysterious find set off a heated debate about whether Antarctica had thawed enough at some point within the last few million years for the emergence of algae-rich seas in the middle of the continent, or whether the diatoms were blown far inland by wind. Now, a new study links the two hypotheses: Researchers led by Reed Scherer of Northern Illinois University found that the algae were likely deposited by strong winds after substantial ice-sheet melt led to sea-level rise along eastern Antarctica.

23 Dec 2016

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