Scientists from NASA and the Commerce Department's National Oceanic and Atmospheric Administration (NOAA) have confirmed the ozone hole over the Antarctic this September is not only much smaller than it was in 2000 and 2001, but has split into two separate "holes."

A new NASA climate study has found that large amounts of black carbon (soot) particles and other pollutants are causing changes in precipitation and temperatures over China and may be at least partially responsible for the tendency toward increased floods and droughts in those regions over the last several decades.

The NASA Jet Propulsion Laboratory (JPL) Frequency Standards Laboratory team has developed and installed a new trapped ion atomic clock for the U.S. Naval Observatory in Washington that is expected to provide 20 times improved stability and accuracy over previous trapped ion clocks.

A new NASA-funded study used a computer climate model to simulate the last 50 years of climate changes, projects warming over the next 50 years regardless of whether or not nations curb their greenhouse gas (GHG) emissions soon. If no emission reductions are made and they continue to increase at the current rate, global temperatures may increase by 1-2º Celsius (1.8º-3.6º Fahrenheit). But if the growth rate of carbon dioxide does not exceed its current rate and if the growth of true air pollutants (things that are harmful to human health) is reversed, temperatures may rise by only 0.75C (1.35F).

Over warmer ocean waters, tropical storm clouds become thicker, more extensive and reflect more sunlight back into space than they do over cooler waters, NASA researchers report.

Driven by precise new satellite measurements and sophisticated new computer models, a team of NASA researchers is now routinely producing the first global maps of fine aerosols that distinguish plumes of human-produced particulate pollution from natural aerosols.

Researchers from NASA's Jet Propulsion Laboratory, Pasadena, California, have shown that although radio signals from the constellation of global positioning system (GPS) navigation satellites orbiting Earth are very weak, they can be detected by airborne instruments and used to map ocean eddies.

Six months into its mission to precisely measure Earth's shifting water masses and map their effects on Earth's gravity field, the joint NASA-German Aerospace Center Gravity Recovery and Climate Experiment, or Grace, is already producing results of considerable interest.

NASA scientists will venture into an isolated part of the Bolivian Amazon to try and uncover the origin of a 5 mile (8 kilometer) diameter crater there known as the Iturralde Crater. Traveling to this inhospitable forest setting, the Iturralde Crater Expedition 2002 will seek to determine if the unusual circular crater was created by a meteor or comet.