ABSTRACT
Jean Baptiste Boussingault was a nineteenth century French agricultural and analytical chemist. He sampled gas emissions from fumaroles near one of the many volcanoes and found carbon dioxide to be present. On returning to France, he made careful measurements of the atmosphere and was the first to determine that carbon dioxide in air was between 280 and 310 parts per million by weight. Annual consumption of carbon dioxide by photosynthesis is about 270 gigatons of carbon dioxide. Air is composed mostly of nitrogen. At the altitude in the islands, the air measured is very clean, monitoring was done continuously, wind corrections were easily accommodated, and instrument calibrations were checked every half hour. The average concentration increased steadily from 315 ppm to just over 400 ppm into the twenty-first century. There are mountains and valleys with corresponding decreasing or increasing air pressure, respectively, complicates the calculation.
