Group items tagged

An animated Robert Krulwich chemistry lesson -- in five episodes. [Correction The on-air version of this story stated that energy is released when carbon-atom bonds are broken. To be more precise, energy is released after the bond is broken and carbon atoms grab on to other atoms.]

Aerosols Altered Asian Monsoons Summer monsoons provide much of the water for farming on the Indian subcontinent, but the pattern of rain shifted dramatically during the last half of the 20th century. In a study appearing online 29 September in Science, researchers pin the blame on soot and other aerosols from human activities. From 1951 to 1999, central-northern India became drier while Pakistan, northwestern India, and southern India got wetter. To determine whether these changes were due to natural variability or human interference (greenhouse gases or aerosols), climate scientists Massimo Bollasina, Yi Ming, and V. Ramaswamy of the Geophysical Fluid Dynamics Laboratory/NOAA in Princeton, New Jersey, compared the history of rainfall with simulations that singled out each climate "forcing" factor to observe its impact. Although greenhouse gases would have increased rainfall over north-central India, the aerosols, they found, caused the "very pronounced drying trend," Ming says. Here's why: Under normal conditions, the northern hemisphere receives more energy from the sun from June to September; that imbalance drives the ocean-atmosphere circulation that powers the monsoons. But atmospheric aerosols shaded the northern hemisphere relative to the southern hemisphere, altering the energy balance between the two-weakening the circulation and altering where the rain falls.

Nature has evolved efficient strategies to synthesize complex mineralized structures that exhibit exceptional damage tolerance. One such example is found in the hypermineralized hammer-like dactyl clubs of the stomatopods, a group of highly aggressive marine crustaceans. The dactyl clubs from one species, Odontodactylus scyllarus, exhibit an impressive set of characteristics adapted for surviving high-velocity impacts on the heavily mineralized prey on which they feed. Consisting of a multiphase composite of oriented crystalline hydroxyapatite and amorphous calcium phosphate and carbonate, in conjunction with a highly expanded helicoidal organization of the fibrillar chitinous organic matrix, these structures display several effective lines of defense against catastrophic failure during repetitive high-energy loading events.

The Carbon Cycle What Goes Around Comes Around by John Arthur Harrison, Ph.D. Carbon is the fourth most abundant element in the universe, and is absolutely essential to life on earth. In fact, carbon constitutes the very definition of life, as its presence or absence helps define whether a molecule is considered to be organic or inorganic. Every organism on Earth needs carbon either for structure, energy, or, as in the case of humans, for both. Discounting water, you are about half carbon. Additionally, carbon is found in forms as diverse as the gas carbon dioxide (CO2), and in solids like limestone (CaCO3), wood, plastic, diamonds, and graphite.

- Welcome to the Global Warming Wheel Card Classroom Activity Kit (PDF) (2 pp, 2.4 MB, About PDF) - Instructions for Making a Global Warming Wheel Card (unassembled) (PDF) (5 pp, 2.4 MB, About PDF) - Guide for Teachers (including Teacher Notes on Activities) (PDF) (3 pp, 1.3 MB, About PDF) - Frequently Asked Questions About Global Warming and Climate Change: Back to Basics (PDF) (8 pp, 1.6 MB, About PDF) - Activity #1: Using the Global Warming Wheel Card (PDF) (2 pp, 1.4 MB, About PDF) - Homework for Activity #1: Electricity Use and Carbon Dioxide (PDF) (1 pp, 1.3 MB, About PDF) - Activity #2: What You and Your Community Can Do to Reduce Carbon Dioxide (PDF) (1 pp, 1.3 MB, About PDF) - Activity #3: A Simple Energy Audit (PDF) (3 pp, 1.3 MB, About PDF)

"Scientific Workforce NSF Touts Family-Friendly Policies as Boon to Women 1. Jeffrey Mervis Young women are forever asking Meg Urry, an astrophysicist at Yale University, if it's possible "to have a successful scientific career and a family." A tenured professor with both, Urry tells them "yes." Perhaps more telling, however, is that the issue doesn't seem to interest half of her students. "I've never been asked that question by a man," she says. This week, the National Science Foundation (NSF) rolled out a set of family-friendly policies that it hopes will reduce the number of young women who jettison scientific careers because of responsibilities outside the lab. "Too many women give up because of conflicts between their desire to start a family and their desire to ramp up their careers," says John Holdren, the president's science adviser and head of the Office of Science and Technology Policy. It was a rare moment in the spotlight for the low-profile basic research agency: First Lady Michelle Obama announced the policies at a White House ceremony touting the importance of women to the nation's economic recovery and, in particular, the need to improve the proportion of women in the so-called STEM (science, technology, engineering, and mathematics) workforce. Figure View larger version: * In this page * In a new window Lending a hand. First Lady Michelle Obama applauds the work of young women in science at a White House event. "CREDIT: NATIONAL SCIENCE FOUNDATION" The new policies will allow both male and female grant recipients to defer an award for up to 1 year or receive a no-cost extension of an existing grant. NSF also hopes to increase its use of "virtual reviews" of grant proposals so that scientists don't need to travel as often to the agency's Arlington, Virginia, headquarters. The only change with any price tag attached is a new program of supplemental awards to investigators going on family leave, allowing them to hi

Table of Contents About Science for All Americans and Atlas of Science Literacy.................................................. 4 From Chapter 1: The Nature of Science ............................... 5 From Chapter 3: The Nature of Technology ......................... 7 Map: Scientifi c Investigations ............................................. 11 Map: Interaction of Technology and Society ..................... 13 Map: Decisions about Using Technology ........................... 15 From Chapter 4: The Physical Setting ............................... 16 Recommended Reading ..................................................... 17 Map: Weather and Climate .................................................. 19 Map: Use of Earth's Resources ............................................ 21 From Chapter 8: The Designed World ................................ 22 From Chapter 5: The Living Environment .......................... 23 Map: Energy Resources ...................................................... 25 Map: Interdependence of Life ............................................ 27 Recommended Reading ..................................................... 28 Web Sites for Climate Change Resources ........................... 29

Science 8 July 2011: Vol. 333 no. 6039 pp. 173-175 Galaxy Zoo Volunteers Share Pain and Glory of Research 1. Daniel Clery A project to "crowdsource" galactic classifications has paid off in ways the astronomers who started it never expected. Figure View larger version: * In this page * In a new window Space oddity. Greenish "voorwerp" spotted by a Dutch volunteer still intrigues scientists. "CREDIT: NASA, ESA, W. KEEL (UNIVERSITY OF ALABAMA), AND THE GALAXY ZOO TEAM" The automated surveys that are becoming increasingly common in astronomy are producing an embarrassment of riches for researchers. Projects such as the Sloan Digital Sky Survey (SDSS) are generating so much data that, in some cases, astronomers don't know what to do with them all. SDSS has compiled a list of more than 1 million galaxies. To glean information about galaxy evolution, however, astronomers need to know what type of galaxy each one is: spiral, barred spiral, elliptical, or something else. At present, the only reliable way to classify galaxies is to look at each one. But the SDSS list is so long that all the world's astronomers working together couldn't muster enough eyeballs for the task. Enter the "wisdom of crowds." An online effort called Galaxy Zoo, launched in 2007, set a standard for citizen-scientist participation projects. Zealous volunteers astonished the project's organizers by classifying the entire catalog years ahead of schedule. The results have brought real statistical rigor to a field used to samples too small to support firm conclusions. But that's not all. Buoyed by the curiosity and dedication of the volunteers, the Galaxy Zoo team went on to ask more-complicated classification questions that led to studies they hadn't thought possible. And in an online discussion forum on the Galaxy Zoo Web site, volunteers have pointed to anomalies that on closer inspection have turned out to be genuinely new astronomical objects. "I'm incredibly impres

"Oil Exploration Oil Exploration Gulf Drilling Disaster Triggers Scrutiny of Mediterranean Oil Rush 1. Laura Margottini* A rush to find and extract oil in the Mediterranean Sea is threatening one of the planet's marine biodiversity hot spots, scientists warn. PANTELLERIA, ITALY-This tiny speck in the Mediterranean, home to a few thousand people, seems like one of the most tranquil places in the world. But looks are deceptive. Pantelleria, in the Strait of Sicily halfway between Palermo and Tunis, is close to one of the world's busiest shipping lanes, and of late, its waters have also become the center of a new oil rush. Attracted by Italy's easygoing drilling regulations and low tax on oil extraction, dozens of companies have new plans for exploration and drilling in this part of the Mediterranean Sea. At a recent meeting here,* however, scientists, conservationists, and environmental activists warned that such efforts put several important biodiversity hot spots in danger. An oil disaster like the Deepwater Horizon explosion, which sent oil gushing into the Gulf of Mexico for months, could easily ruin the Mediterranean ecology for a century or longer, some said. The Italian government has recently issued 66 permissions for drilling around its coasts and 25 concessions for exploration. Another 67 applications for exploration are under review. "Italy now represents the region that holds the most exciting and significant long-term opportunities," one company, Northern Petroleum, says on its Web site. The Strait of Sicily is the center of attention, but other biodiversity hot spots, such as the Tremiti Islands in the Adriatic Sea, could soon be explored as well. Italy isn't alone. Tunisia, for example, has granted concessions for oil exploration for most of its Mediterranean waters, without much political opposition. But the areas coveted by oil companies are ecological treasures, researchers and groups such as Greenpeace Italy stress. Last year, the Uni

Encyclopedia of Earth

"Slowing climate change requires overcoming inertia in political, technological, and geophysical systems. Of these, only geophysical warming commitment has been quantified. We estimated the commitment to future emissions and warming represented by existing carbon dioxide-emitting devices. We calculated cumulative future emissions of 496 (282 to 701 in lower- and upper-bounding scenarios) gigatonnes of CO2 from combustion of fossil fuels by existing infrastructure between 2010 and 2060, forcing mean warming of 1.3°C (1.1° to 1.4°C) above the pre-industrial era and atmospheric concentrations of CO2 less than 430 parts per million. Because these conditions would likely avoid many key impacts of climate change, we conclude that sources of the most threatening emissions have yet to be built. However, CO2-emitting infrastructure will expand unless extraordinary efforts are undertaken to develop alternatives. "