Scientists suspected the 2015-16 El Nino -- one of the largest on record -- was responsible, but exactly how has been a subject of ongoing research. Analyzing the first 28 months of data from NASA’s Orbiting Carbon Observatory-2 (OCO-2) satellite, researchers conclude impacts of El Nino-related heat and drought occurring in tropical regions of South America, Africa and Indonesia were responsible for the record spike in global carbon dioxide. The findings are published in the journal Science Friday as part of a collection of five research papers based on OCO-2 data.
These findings, published in one of five studies coming out today in Science, represent just the first batch of discoveries from a mission NASA launched in 2014. The satellite, called Orbiting Carbon Observatory-2, or OCO-2, is designed to monitor carbon dioxide in our planet’s atmosphere. CO2 levels have been increasing since the Industrial Revolution in the 1800s, and because CO2 is a heat-trapping greenhouse gas, our planet is warming up. Today, we keep pumping out huge amounts of carbon by burning fossil fuels, but about 25 percent of those emissions are absorbed by the ocean, and another 25 percent is vacuumed up by plants. Today’s papers are the beginnings of explanations about how this carbon is taken up, and if these processes will last as the world continues to warm.
“There’s a lot of uncertainty on what the world might be like in 100 years, and understanding more of what we’re seeing now can help us predict better what the future holds,” says Annmarie Eldering, the deputy project scientist for the OCO-2 mission at NASA’s Jet Propulsion Laboratory (JPL), and the co-author of a few of the studies.
The OCO-2 satellite zooms around the Earth over 14 times a day, gathering about 100,000 measurements per day — including in areas that haven’t been observed much before, like the middle of the ocean and the Amazon rainforest. Using that data, researchers put together a map of CO2 concentrations over the planet, to see how the gas is absorbed and emitted, and how it’s dispersed into the atmosphere.