Mauna Loa Observatory (MLO) 2

The Mauna Loa Observatory (MLO) is an atmospheric baseline station on Mauna Loa, Hawaii. Since 1958, MLO has been collecting data relating to atmospheric change, and is known especially for the continuous monitoring of atmospheric carbon dioxide (CO2). The observatory is under the Earth System Research Laboratory which is part of the National Oceanic and Atmospheric Administration (NOAA). According to the NOAA, Mauna Loa is the world's oldest continuous CO2 monitoring station, and the world's primary benchmark site for measurement of the gas.