GEOLOGY

Detailed explanation-1: -Perched on a barren volcano in the middle of the Pacific Ocean, the Mauna Loa observatory is a benchmark sampling location for CO2.

Detailed explanation-2: -The Mauna Loa Observatory of the National Oceanic and Atmospheric Administration, where the world’s primary atmospheric carbon dioxide measurements have been taken since 1958.

Detailed explanation-3: -In 1957 Dave Keeling, who was the first to make accurate measurements of CO2 in the atmosphere, chose the site high up on the slopes of the Mauna Loa volcano because he wanted to measure CO2 in air masses that would be representative of much of the Northern Hemisphere, and, hopefully, the globe.

Detailed explanation-4: -Carbon dioxide – the gas scientists say is most responsible for global warming – peaked again at record levels last month, scientists announced Tuesday. Levels at Hawaii’s Mauna Loa Observatory averaged 414.8 parts per million in May, surging past yet another climate milestone.

Detailed explanation-5: -The Northern Hemisphere dominates the annual cycle of CO 2 concentration because it has much greater land area and plant biomass than the Southern Hemisphere. Concentrations reach a peak in May as the Northern Hemisphere spring greenup begins, and decline to a minimum in October, near the end of the growing season.