Mauna Loa Observatory
The Mauna Loa Observatory (MLO) on the Big Island of Hawaii is located on the north flank of Mauna Loa Volcano. Since 1956 this atmospheric research facility has continuously overseen and collected data related to atmospheric and climate change. Mauna Loa was initially selected as a monitoring site because of its location which is far from any landmass. The air sampled from the area also presents a good average for the central Pacific region, although contamination from local volcanic activity is sometimes detected by the observatory and is then removed from background data. The Mauna Loa Observatory is not open to the public but tours are available but by appointment only.