Earth
We summarize the week's scientific breakthroughs every Thursday.
- Earth
Contaminants still lace some meats
Tainted ingredients of livestock feed can contribute to worrisome residues of organochlorines, such as PCBs, ending up in meat.
- Earth
Plastic debris picks up ocean toxics
Some plastics can accumulate toxic pollutants from water, increasing the risk that they might poison wildlife mistaking these plastics for food.
- Earth
Resuscitating the Gulf’s dead zone
State, federal, and Indian agencies have joined forces to develop policies aimed at stemming a huge, seasonal zone in the Gulf of Mexico where oxygen levels are too low to sustain most aquatic life.
- Earth
Eye above the Timberline
The Tundra-Cam, operated by the University of Colorado’s Institute of Arctic and Alpine Research, sits at an elevation of 11,600 feet near the U.S. Continental Divide. Visitors to the Web site can operate the remotely controlled webcam, panning across the mountainous landscape and zooming in on particular features of interest. Go to: http://tundracam.colorado.edu
- Earth
Pinning Down the Sun-Climate Connection
Many scientists propose that changes in the sun's magnetic field and radiation output during its 11-year sunspot cycle also affect the atmosphere, changing Earth's climate by steering weather systems and influencing the amount of cloud cover.
- Earth
Amazon basin is wetter now than in past
Sediments from the Atlantic Ocean indicate that the now lush Amazon Basin was much drier during the latest ice age.
- Earth
Explorers pinpoint source of the Amazon
A five-nation team of explorers has used Global Positioning System equipment to confirm that the source of the Amazon is a snowmelt-fed stream high in the Peruvian Andes.
- Earth
Scientists analyze volcanoes’ killing ways
Death patterns from more than 400 volcanic eruptions through history may reveal ways to reduce the number of fatalities from similar causes in the future.
- Earth
Lake sediment tells of Maya droughts
Sediment cores taken last year from the bottom of a lake on Mexico's Yucatán peninsula indicate that a series of extended droughts coincided with major cultural upheavals among the Mayan inhabitants of the area.
- Earth
Sediments show bipolar melting cycle
Both the North and South Poles have experienced regular and simultaneous periods of significant melting during the past 3 million years, according to sediments from the ocean floor at high latitudes.
- Earth
Snowpack chemistry can deplete ozone
Pollutants trapped in Arctic snow can be reactivated by sunlight when the sun returns to high latitudes in the spring, leading to ozone depletion in the snowpack and at low altitudes.
- Earth
Pollution in India may affect climate
Computer models show that air pollution over India could be preventing up to 15 percent of the sunlight from reaching the ground in the springtime, possibly causing temperature drops of up to 2 degrees Celsius.
