What poses the greater risk, traffic accidents or air pollution?

When a London anti-pollution organisation polled British lawmakers about the greatest risks to public health, most MPs were wrong, ranking traffic accidents or heavy drinking ahead of air pollution as a leading killer of Britons. "The vast majority of over 100 members of Parliament responding to our survey displayed a shocking level of ignorance about the health impact of air pollution," said Simon Birkett, head of Clean Air in London, an advocacy group. “"n particular, over two-thirds of Conservative MPs responding said air pollution has less impact than road traffic accidents," he said on releasing the survey results on 23 May.

Ocean Denitrification

Denitrification is a microbially facilitated process of nitrate reduction that may ultimately produce molecular nitrogen (N2) through a series of intermediate gaseous nitrogen oxide products. In general, it occurs where oxygen, a more energetically favorable electron acceptor, is depleted, and bacteria respire nitrate as a substitute terminal electron acceptor. Denitrification only takes place in anoxic environments where oxygen consumption exceeds the oxygen supply and where sufficient quantities of nitrate are present. As ice sheets melted during the deglaciation of the last ice age and global oceans warmed, oceanic oxygen levels decreased and denitrification accelerated by 30 to 120 percent, a new international study shows, creating oxygen-poor marine regions and throwing the oceanic nitrogen cycle off balance. By the end of the deglaciation, however, the oceans had adjusted to their new warmer state and the nitrogen cycle had stabilized – though it took several millennia. Recent increases in global warming, thought to be caused by human activities, are raising concerns that denitrification may adversely affect marine environments over the next few hundred years, with potentially significant effects on ocean food webs.

Indigenous Knowledge

It is time to stop discounting traditional expertise and make use of this vast and valuable resource, argues Indian scientist Suman Sahai. Science and technology have always been an important part of growth and development plans. But accepted 'scientific expertise' is Western, standardised and homogenous. From this viewpoint, the vast body of scientific expertise developed in diverse societies and cultures is discounted and ignored. Referred to as indigenous or traditional knowledge, this is a knowledge system distilled from generations of scientific work anchored in rural and tribal communities. It is different to the Western system of empirical, lab-based science — but is equally valid and efficacious.

Frozen Dione

Dione is the 15th largest moon in the Solar System, and is more massive than all known moons smaller than itself combined. It is composed primarily of water ice, but as the third densest of Saturn's moons (after Enceladus and Titan, whose density is increased by gravitational compression) it must have a considerable fraction (~ 46%) of denser material like silicate rock in its interior. So it is much like a frozen snowball, inert and dead. Thanks to close-up images of a 500-mile-long (800-kilometer-long) mountain on the moon from NASA's Cassini spacecraft, scientists have found more evidence for the idea that Dione was likely geologically active in the past. It could still be active now.

Data from NASA’s Landsat 8 now available in almost real time

Data from NAA's Landsat 8 is now freely available, enabling researchers and the general public to access images captured by the satellite within twelve hours of reception. The data is available to download at no charge from GloVis, EarthExplorer, or via the LandsatLook Viewer. Landsat 8 launched this February and has been capturing images since April. The satellite orbits Earth every 99 minutes and captures images of every point on the planet every 16 days, beaming 400 high resolution images to ground stations every 24 hours. Landsat features nine spectral bands, which include three visible light bands, two near-infrared bands, and two shortwave infrared (SWIR) bands, among others, as well as two thermal sensors, which are used for a wide range of applications, including monitoring environmental change, detecting fires, and watching crops. Google is one of the biggest commercial users of Landsat images, which feed into Google Earth, but other users include scientists and conservationists involved in tracking deforestation and forest degradation.

Rainforests will survive extreme global warming, argues study

Rainforests in South America have survived three previous extreme global warming events in the past, suggesting that they will survive a projected 2-6 degree rise in temperatures over the coming century, reports a study published in the Annual Review of Earth and Planetary Science. The research, published by Carlos Jaramillo and Andrés Cárdenas of the Smithsonian Tropical Research Institute (STRI) in Panama, reviewed some 3,800 published estimates of temperature over the past 120 million years and compared them to the existence of tropical plants in the fossil record.