420 410 400 The Keeling Curve 390 Measurements of carbon dioxide concentrations in the atmosphere from the Mauna Loa Observatory, in parts per million CO2. In the meantime, officials are contemplating flying in a generator via helicopter to the Mauna Loa observatory, which is operated by the National Oceanic and Atmospheric Administration. ISLAND OF HAWAI‘I Mauna Loa Observatory Lava flow Eruption began at Moku‘āweoweo caldera Mauna Loa Honolulu Hawai‘i Hawaiian Islands Area of detail Honolulu Hawai‘i Hawaiian Islands Area of detail ISLAND OF HAWAI‘I Mauna Loa Observatory Lava flow Eruption began at Moku‘āweoweo caldera Mauna Loa Source: Copernicus Notes: Image captured by satellite on Nov. 28, 2022. But none hold quite the same symbolism as Mauna Loa, which is home to the first and most frequently cited data. Even now, when scientists want to test new carbon dioxide monitoring equipment, “they go to Mauna Loa,” Dr. Sweeney said.

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