Atmospheric Radiation Measurement User Facility

The Atmospheric Radiation Measurement User Facility (ARM User Facility or ARM), a multi-laboratory U.S. Department of Energy Office of Science user facility, provides 30-plus years of atmospheric measurements, including data sets from all seven continents and five oceans, to advance the understanding of the Earth’s atmosphere. The ARM User Facility consists of three instrumented fixed-location atmospheric observatories, as well as mobile and aerial observatories.

Source: Wikipedia — Atmospheric Radiation Measurement User Facility (CC BY-SA 4.0)