NASA Probe Sees Solar Wind Decline
The 33-year odyssey of NASA's Voyager 1 spacecraft has reached a distant point at the edge of our solar system where there is no outward motion of solar wind. Now hurtling toward interstellar space some 17.4 billion...
Super-Earth Atmosphere
A team of astronomers, including two NASA Sagan Fellows, has made the first characterizations of a super-Earth's atmosphere, by using a ground-based telescope...
Kepler Discovers
NASA's Kepler spacecraft has discovered the first confirmed planetary system with more than one planet crossing in front of, or transiting, the same star...
A new analysis, published this week and conducted by a team of scientists led by Drew Shindell of NASA's Goddard Institute for Space Studies (GISS) in New York City, shows stricter vehicle emission standards would yield major health, agricultural, and climate benefits.
Shindell and colleagues used a comprehensive computer model and climate simulator -- one of the first capable of accounting for the role of short-lived particles expelled in vehicle fumes called aerosols -- that shows vehicle fumes exact an enormous toll in all countries and especially in the developing world.
The scientists used modeling techniques developed at GISS to compare a baseline scenario that assumes existing emission standards remain unchanged in coming decades with a second scenario that has most countries adopting stringent standards similar to those in place in Europe and North America. Vehicles in those two regions produce less particulate matter and less polluting gases, such as nitrous oxides and carbon monoxide, due to the use of particle filters and cleaner-burning fuels.
The aggressive scenario assumes, for example, that China, India, and Brazil adopt "Euro 6" standards by 2015, a regime that would reduce emissions of particulate matter by about 85 percent, nitrogen oxides by about 65 percent, and carbon monoxide by about 70 percent for passenger vehicles. The aggressive scenario assumes major emissions reductions in Latin America, Africa, and the Middle East, the regions with the laxest emissions standards. Emissions rules in North America are slightly more stringent than European standards already, so in North America the baseline and aggressive scenarios were identical.