Taxonomy term

timothy oleson

Bare Earth Elements: Past and present directors dissect the future of USGS

The U.S. Geological Survey, including its employees and leadership, have a penchant for self-assessment and an ambition for pragmatic self-improvement. That was on display Thursday, Dec. 18, in San Francisco in an hour-long panel discussion held in conjunction with the annual fall meeting of the American Geophysical Union, and featuring USGS acting director Suzette Kimball along with four of the five most recent past directors and acting directors. The panelists candidly addressed a number of issues, including how USGS has been and should continue adapting to best address its roles in science and public service, as well as internal and external barriers affecting its success in these roles.

22 Dec 2014

Carbon tet still offensive to ozone layer

Earth’s ultraviolet light-shielding ozone layer is recovering, according to a report released in September by the World Meteorological Organization and the United Nations Environment Programme. The findings, authored by more than 250 scientists and presented as part of the latest Scientific Assessment of Ozone Depletion (SAOD), suggest the ongoing success of the 1987 Montreal Protocol and its amendments in cutting atmospheric levels of chlorofluorocarbons (CFCs) and other ozone-depleting substances (ODS’s), which have fallen by about 10 to 15 percent overall since peaking in the late 1990s.

22 Dec 2014

Last Scottish glacier melted during big chill?

Scotland’s craggy peaks, deep lochs and fjord-lined coast are hallmarks of a landscape shaped by successive glaciations, the last of which, toward the end of the Pleistocene, draped the highlands with an ice cap covering 9,500 square kilometers. Rocky moraines give scientists a clear picture of the boundaries of this glaciation, called the Loch Lomond Advance, although the timeline of its growth and eventual demise has proved difficult to pin down.

18 Dec 2014

Limited ranges left ammonites vulnerable to extinction

Why spiral-shelled, ocean-faring ammonites went extinct at the end of the Cretaceous while the nautilids — the ammonites’ less abundant and less diverse cephalopod relatives — survived has long puzzled paleontologists. Nautilids tended to dwell deeper in the ocean than ammonites, perhaps keeping them farther out of harm’s way after the asteroid struck, which likely led to acidification of the ocean surface. Now, a new study suggests that the animals’ geographic range may have contributed to which ones lived and which ones died.

13 Dec 2014

Pliocene tropical oceans were warmer after all

Scientists may have overturned the idea that Earth’s tropical oceans were the same temperature during the Early to Middle Pliocene — between about 5 million and 3 million years ago — as they are today, despite the world being a far warmer place then.

12 Dec 2014

Better flood forecasts eyed from space

Satellite measurements of total water storage in river basins — including surface waters, snow, groundwater and soil moisture — may help indicate, months in advance, whether those basins will be predisposed to major flooding, according to new research published in Nature Geoscience. Thus, they could help improve on conventional flood forecasts, which are often based on shorter-term weather forecasts combined with incomplete estimates of basin saturation and offer abbreviated lead times for predictions.

09 Dec 2014

Beware the list that skews your view

List-making is an almost universal human endeavor. Some of us still scrawl them on paper; some tap them out on virtual sticky notes on phones and computers. Others, using mnemonic devices or sheer willpower, keep track in their heads. (I’m partial to the ink-on-paper medium, though I stray occasionally.) Whatever the case, I don’t know anyone who doesn’t make lists.

01 Dec 2014

Red Planet Roundup: November 2014

As Curiosity and Opportunity rove around Mars, the Mars Reconnaissance Orbiter (MRO), Mars Express and Mars Odyssey orbit above, and scientists on Earth study the Red Planet from afar, new findings are announced almost weekly. Here are a few of the latest updates.

06 Nov 2014

Clues to limestone weathering written in Western Wall

Builders and masons take note: When it comes to the durability of limestone, grain size matters. New research combining field and lab data shows that fine-grained limestone is more susceptible than its coarser-grained cousins to a one-two punch of chemical and mechanical weathering. The findings, which arose in part from observations of Jerusalem’s historic Western Wall, could have implications for Earth’s carbon cycle and landscape — as well as for architectural preservation.

16 Oct 2014

Ice (Re) Cap: October 2014

From Antarctica to the Arctic; polar caps, permafrost and glaciers to ocean-rafted sea ice; and burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

12 Oct 2014

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