The Intercontinental Chemical Transport Experiment – North America (INTEX-NA) was an integrated field campaign which quantified and characterized the transport of gases and aerosols on transcontinental and intercontinental scales. INTEX-A, the first phase of this experiment, was conducted in the summer of 2004. The second phase of the mission, INTEX-B, was conducted in the spring of 2006. This field experiment sought to quantify and characterize the transport of gases and aerosols on transcontinental and intercontinental scales. INTEX-B focused on the transpacific inflow of pollution from Asia to North America as well as the impact of pollution outflow from Mexico City across North America. These two factors play a key role in the atmospheric transport of pollution across North America.

The primary objectives of INTEX-B were to quantify the transport of pollution from Asia to North America in order to understand its impacts on regional air quality and climate; to quantify the inflow and outflow of gases and aerosols from Mexico City; and to assess the implications for European air quality of the transport of pollution from Asia and North America to the east coast of the United States and the Atlantic Ocean. Additionally, INTEX-B sought to validate satellite observations, to map trace gas and aerosol emissions, and to relate atmospheric composition to the sources and sinks of trace gases and aerosols.

INTEX-B was conducted in March and April of 2006. INTEX-B/Part I was performed in March with a focus on the outflow of pollution from Mexico City. Subsequently, INTEX-B/Part II was performed in April with a focus on the transpacific inflow of pollution from Asia. The geographic focus of INTEX-B was on the western United States and the Pacific Ocean. Transpacific inflow of pollution from Asia is episodic, but peaks in spring; thus, the planning of the second phase for spring addressed the peak season for transpacific pollution transport.

The NASA DC-8 was the primary platform used in INTEX-B, and the NSF/NCAR C-130 and DLR Falcon-20 acted as complementary platforms. The DC-8 served as a high altitude long-range aircraft, while the NSF/NCAR C-130 served as a low altitude aircraft, and the DLR-Falcon-20 served as a high altitude medium-range aircraft. These platforms were equipped with in-situ and remote sensing instruments to provide chemical, physical, and optical measurements of long-lived greenhouse gases, ozone, ozone precursors, aerosols, aerosol precursors, radicals, radical reservoirs, chemical tracers of sources and transport, and optical parameters. INTEX-B existed in collaboration with several national and international partners. INTEX-B leveraged data from NASA’s Terra, Aqua, and Aura satellites, as well as the European Space Agency’s Envisat satellite. Surface networks and sondes provided ground-based data.

INTEX-B Project Page