NARSTO_PAC2001_GOLDEN_EARS_GAS_PM_DATA is the North American Research Strategy for Tropospheric Ozone (NARSTO) Pacific 2001 Air Quality Study (PAC2001) Golden Ears Gaseous, Particulate Matter (PM), and Meteorological Data product. Data was obtained from August 3-11, 2001 during PAC2001. The Golden Ears Provincial Park (GEP) site was situated at 49.27783 N, 120.51544 W, and 220 m above sea level (a.s.l.), about 45 km east of Vancouver in the Coastal Mountains. The sampling site, located at the park ranger headquarters compound, was in a small forest clearing of about 65 x 130 m and was surrounded by tall coniferous trees (dominated by Western Hemlock, Western Red Cedar, and Douglas Fir, typically seen in the Coastal Mountains) with canopy heights about 10-15 m near the site but rising to over 30 m in the park in general. The temporary labs were about 10 m away from the closest trees. The closest urban area, Maple Ridge, is about 8 km to the south. Different from the other sites, the Golden Ears Provincial Park site was dedicated to the question of secondary biogenic particles production from forestry precursors. The 1995 emission inventories for the LFV indicate strong monoterpene emissions from forests in the Coastal Mountains and the Cascade Ranges. A previous study here showed significant ambient concentrations of terpenes. Monoterpenes are converted into particles in the gas phase with high yields. While the forests were known to release monoterpenes, the magnitude of the contribution to fine particles in the LFV was not clear. Measurements at the GEP site were designed to provide information on secondary biogenic particle production from forestry precursors, such as monoterpenes. PAC2001 was conducted from August 1 to September 31, 2001 in the Lower Fraser Valley (LFV), British Columbia, Canada. The study consisted of individual research projects organized to address several issues on ambient PM and ozone that are important to policy makers. A special issue of Atmospheric Environment [Vol. 38(34), Nov 2004] described specific study objectives (Li, 2004) and presented a series of results papers from the field study. There were 5 ground sampling sites during the study, which included: Cassiar Tunnel, Slocan Park, Langley Ecole Lochiel, Sumas Eagle Ridge, and Golden Ears Provincial Park. Aloft measurements were taken from a Convair 580 and a Cessna 188. Selected measurement data were compiled for each site and aircraft and are archived as site-specific data sets.North American Research Strategy for Tropospheric Ozone (NARSTO), which has since disbanded, was a public/private partnership, whose membership spanned across government, utilities, industry, and academe throughout Mexico, the United States, and Canada. The primary mission was to coordinate and enhance policy-relevant scientific research and assessment of tropospheric pollution behavior; activities provide input for science-based decision-making and determination of workable, efficient, and effective strategies for local and regional air-pollution management. Data products from local, regional, and international monitoring and research programs are still available.