By studying the springtime airflow from Asia across the Pacific, NASA
scientists intend to collect information to learn how natural and
human-induced changes affect our global climate.

The Transport and Chemical Evolution over the Pacific (TRACE-P)
experiment begins its 45-day operation this month from Hong Kong and
finishes at Yokota Air Base near Tokyo, Japan. The mission is using
two specially equipped NASA aircraft to measure gases and identify
the chemical makeup of air off
the East Asian coast over the Pacific Ocean.

A DC-8 from NASA’s Dryden Flight Research Center, Edwards, Calif.,
and a P-3B from NASA’s Wallops Flight Facility, Wallops Island, Va.,
will gather information, augmented by satellites and ground stations.

A major goal of TRACE-P is to understand the makeup and chemical
reactions of air coming from Asia. Researchers want to study how the
chemical reactions and movement affect the air as it sweeps away from
Asia across the Pacific. With rapid industrialization and increased
energy use, mostly in the form of
fossil fuel, scientists expect emissions to increase as East Asia
continues to develop.

TRACE-P is part of the long series of NASA Global Tropospheric
Experiments (GTE) and a follow-up to earlier atmospheric science
investigations in 1991and 1994. These exploratory missions studied
the Asian outflow — air flowing over the continent and across the
Pacific — and how seasons and geography affect
the chemistry and movement of air. GTE is aimed at a better
understanding of worldwide chemistry of the troposphere, which is the
part of the atmosphere closest to the Earth’s surface.

This international research effort is part of NASA’s Office of Earth
Sciences Enterprise, Headquarters, Washington, D.C. The Enterprise is
a long-term research effort dedicated to studying the Earth System
and how it is changing due to both natural and human-induced
processes.