The Boulder Atmospheric Observatory (BAO)
The BAO was a research facility in Erie, Colorado maintained by the NOAA/ESRL Physical Sciences Division, which was used for studying the planetary boundary layer and for testing and calibrating atmospheric sensors. Ongoing measurements included solar radiation and greenhouse gases.
The BAO (initially the NOAA/NCAR/CIRES Joint Meteorological Observatory) was officially accepted from the contractor in October 1977. The first major experiment, Project Phoenix, took place in the fall of 1978. The centerpiece of the facility was a 300-m tower initially instrumented at multiple levels with both fast- and slow-response temperature, relative humidity and wind sensors, had a profiling instrument carriage, a variety of remote sensing systems, and a real-time processing and display capability that greatly reduced analysis time for scientists. Over the years, the BAO hosted several large national and international experiments and numerous smaller ones.
The BAO's legacy officially came to an end as of July 31, 2016. A closing reception was held at the site on November 3, 2016, to help remember and celebrate nearly 40 years of professional excellence.
Additional information about the BAO can be found in a historical essay published in the Bulletin of the American Meteorological Society in July 2018.