NASA Ready to Launch Replacement OCO Satellite for Measuring Atmospheric CO2

NASA plans to launch next month its first spacecraft dedicated to measuring Earth’s atmospheric carbon dioxide (CO2), the leading human-produced greenhouse gas driving climate change, the agency announced on Thursday.

Called the Orbiting Carbon Observatory-2 (OCO-2), it replaces the nearly identical OCO, which was lost during a rocket launch failure in 2009.

OCO-2 will carry one instrument with three high-resolution spectrometers that will allow scientists to use light-analyzing processes to estimate concentrations of CO2 and oxygen. The satellite will take measurements over Earth’s sunlit hemisphere, capturing hundreds of thousands of measurements daily from the ground directly below, over oceans, and targeted sites as it passes overhead.

“Climate change is the challenge of our generation,” said Betsy Edwards, OCO-2 program executive at NASA Headquarters in Washington, one of the panelists at the press conference. “OCO-2 will provide new insight into where and how CO2 is moving in and out of the atmosphere…and it’s going to be an unprecedented level of coverage and resolution.”

The carbon cycle — how the planet breathes — remains largely a mystery.  Much of what is known about the role of CO2 comes from ground-based observations at Mauna Loa in Hawaii dating back to 1956, said Mike Gunson, OCO-2 project scientist at the agency’s Jet Propulsion Laboratory (JPL) in California, which manages the mission.   Satellites like OCO-2 can provide a global view.

Atmospheric CO2 is at its highest level in at least the past 800,000 years and nearly 40 billion tons is released annually by human activities such as fossil fuel burning according to the agency.

“Half of what we release is being absorbed by the plants or the oceans, but it is variable from year to year and understanding that variability is really crucial,” Gunson said. “CO2 is very stable and there are few loss processes, if any, once it is in the atmosphere.”

Gunson and his JPL colleagues OCO-2 project manager Ralph Basilio and OCO-2 deputy project scientist Annmarie Eldering were also members of the panel.

With the loss of the original OCO spacecraft, “we didn’t even have one problem to solve,” Basilio said as he described the heartbreak then and the excitement now to complete unfinished business.

The team will see their second chance lift off on a United Launch Alliance Delta II rocket on July 1 at 2:56 a.m. Pacific Daylight Time from Vandenberg Air Force Base in California if the schedule remains on track.

Edwards thanked NASA’s Japanese partners, who she said reached out and invited NASA to participate in analyzing data from their Greenhouse gases Observing SATellite (GOSAT) after the OCO mishap.

The original OCO cost roughly $275 million compared to $465 million for its replacement, Edwards said.  She cited the launch vehicle change (from a Taurus-XL to a Delta II), program delays, reengineering changes and inflation for the cost hike.

OCO-2, which has a design life of two years but sufficient fuel to last beyond that, will lead a line of five other international Earth-monitoring satellites known as the A-Train constellation. Every 16 days the spacecraft will observe the same spot on the globe to help give scientists seasonal as well as annual patterns.

NASA was planning to use OCO-2 spare parts to build OCO-3 and attach it to the International Space Station in late 2016, but budget constraints forced the agency to put that idea on hold.  “We hope to get back to OCO-3,” Edwards said, “but right now the budget doesn’t allow.”

For FY2015, NASA is seeking $21 million to operate OCO-2. The cost is part of the $4,972 million the agency is requesting for its science account, of which $1,770 million is for earth science.  The House-passed FY2015 Commerce-Justice-Science (CJS) appropriations bill would cut that amount slightly, to $1,750 million, while the Senate Appropriations Committee recommended a significant increase to $1,832 million largely because it wants to transfer two NOAA satellite programs to NASA.