Study warns of threats to water security and biodiversity in the world’s rivers.

Only isolated parts of the Amazon have low levels of threat to water security and biodiversity.

Nearly 80% of the world’s population — 4.8 billion people as calculated in 2000 — live in areas experiencing a high level of threats to human water security or biodiversity.

Water-management strategies aimed at improving human water security, such as building dams to provide access to water-starved regions, often detrimentally affects wildlife that also depends on freshwater resources, such as migrating fish.

But a study published in Nature today is the first to consider factors affecting both human water security and biodiversity in its analysis of threats to global freshwater resources, such as pollution and the density of dams1.

“If you analyse water-security issues from both a human and biodiversity perspective, you find that the threats are shared and pandemic. Even rich countries, which you would expect to be good stewards of water, have some of the most stressed and threatened areas,” says Charles Vörösmarty, a civil engineer at the City University of New York, one of the lead investigators of the analysis. Read more

Spinosaurs’ semi-aquatic habits helped them coexist with tyrannosaurs.

Spinosaurs may have spent much of their lives in water. Marc Simonetti

Researchers have found evidence of dinosaurs that spent much of their time in water. The discovery, made by analysing oxygen isotopes found in the fossils of a spinosaur that fed on fish, shows how the dinosaur might have coexisted with other large predators such as tyrannosaurs.

The results, published in Geology by Romain Amiot at the University of Lyon in France and a team of colleagues, show that dinosaurs were not in fact restricted to land as had been previously thought1. Water-dwelling animals such as Plesiosaurus and Ichthyosaurus, which although dinosaur-like in appearance, are not part of the dinosaurian lineage.

Baryonyx walkeri, from the spinosaur family, had a long, crocodile-like skull littered with iconic cone-shaped teeth. When it was found, theories swirled that with piercing teeth, rather than the serrated teeth so often found in closely related meat eaters such as Tyrannosaurus rex, and a long snout, the dinosaur was a fish feeder. Read more

Mysterious changes in the stratosphere may have offset greenhouse effect.

A loss of water vapour from the Earth’s stratosphere may have been behind the last decade being cooler than expected.NASA

A puzzling drop in the amount of water vapour high in the Earth’s atmosphere is now on the list of possible culprits causing average global temperatures to flatten out over the past decade, despite ever-increasing greenhouse-gas emissions.

Although the decade spanning 2000 to 2009 ranks as the warmest on record, average temperatures largely levelled off following two decades of rapid increases. Researchers have previously eyed everything from the Sun and oceans to random variability in order to explain the pause, which sceptics have claimed shows that climate models are unreliable.

Now a team led by researchers at the National Oceanic and Atmospheric Administration (NOAA) in Boulder, Colorado, report that a mysterious 10% drop in water vapour in the stratosphere — the atmospheric layer that sits 10–50 kilometres above Earth’s surface — since 2000 could have offset the expected warming due to greenhouse gases by roughly 25%. Just as intriguingly, their model suggests that an increase in stratospheric water vapour might have boosted earlier warming by about 30% in the 1980s and 1990s. Read more

We place high demands on the quality of our drinking water. If pathogens or toxic substances found their way into the piping system, many people could become infected or injured very quickly. That’s why this risk must be kept low. To do this, experts have developed technologies for a comprehensive monitoring, early warning and emergency management system.

Drinking water is indispensable for every human being. Public works and water utilities must not only protect the supply system from impurities, but also from possible manipulation. Every day, they collect probes and analyze drinking water quality in a lab, but such analysis takes time. Preventative methods and tools are needed for continuous monitoring in order to identify contaminations quickly and also catch unexpected toxic substances. Even a few drops could have devastating consequences – toxins that make their way into the water supply reach millions of users within hours. Read more