NASA's Orbiting Carbon Observatory (OCO)-2 will measure CO2 in the atmosphere

An artists rendition of NASA's Orbiting Carbon Observatory (OCO-2), which will launch on July 1 and measure atmospheric carbon dioxide 

NASA is preparing a July 1 launch for its first satellite dedicated to measuring atmospheric levels of carbon dioxide, a greenhouse gas that plays a key role in climate change.

CO2 levels have reached their highest point in at least 800,000 years, according to the US space agency.

The Orbiting Carbon Observatory (OCO-2) satellite is very similar to its predecessor, OCO-1, which was destroyed during its launch in February 2009.

The satellite will help provide a more complete and global picture of man-made and naturally occurring CO2 emissions as well as the effects of carbon "sinks," like oceans and forests, which absorb and trap the gas.

"Carbon dioxide in the atmosphere plays a critical role in our planet's energy balance and is a key factor in understanding how our climate is changing," said Michael Freilich, director of NASA's Earth Science Division.

"With the OCO-2 mission, NASA will be contributing an important new source of global observations to the scientific challenge of better understanding our Earth and its future," he added in a statement.

The OCO-2 satellite will be launched on a United Launch Alliance Delta II rocket from Vandenberg Air Force Base in California, aiming for an orbit at 438 miles (705 kilometers) above the Earth's surface.

High-speed discovery helps measure greenhouse gases from space

Scientists have discovered how to measure greenhouse gases 200,000 times faster as the result of research by an award-winning PhD student from The University of Western Australia (UWA) and a US team.

The discovery - which is already being used by NASA scientists in Space - has major implications for global warming research, breath analysis (to detect illness), explosives detection, chemical process monitoring and a range of other applications, including fundamental quantum theory.

UWA physics graduate Gar-Wing Truong used highly-sensitive rapid laser scanning technology to help lead US scientists from National Institute of Standards and Technology (NIST) in Maryland to build new gas measurement equipment with unparalleled speed, accuracy, precision and spectral coverage.

NASA's Jet Propulsion Laboratory in California has begun using data from Mr Truong's research to calibrate carbon monitoring satellites in orbit around Earth and better understand carbon dioxide molecules.

Eric May

The research is an extension of Mr Truong's PhD project on precision spectroscopy for gas metrology, which he has conducted at the University since 2009 under the supervision of UWA Winthrop Professor Eric May and former Winthrop Professor Andre Luiten (now at University of Adelaide) , with funding from the Australian Research Council's Discovery program.

Mr Truong said better, more reliable data on global warming held significant benefit to society, helping researchers better understand its causes and accurately evaluate the impact of policy decisions.

"This research is of particular significance to Australia if it is to take the lead in global warming policy and research," Mr Truong said. "It is also highly relevant to WA, where the economy is strongly driven by oil, gas and mineral industries."

Mr Truong, who worked on the new spectroscopy technique while on a year-long Australian Fulbright Fellowship at NIST, said the breakthrough combined ideas already being developed at UWA with apparatus and methods used at NIST.

The resulting novel approach - dubbed Frequency-Agile, Rapid Scanning spectroscopy (FARS) - had greatly improved the speed at which gases could be traced without compromising on precision.

"Usually in science or engineering if you want to make measurements go faster, you have to sacrifice sensitivity," Mr Truong said.

"What we have demonstrated here is a 200,000-fold increase in speed to enable high-precision spectroscopy without degrading sensitivity - we've built a new apparatus with unparalleled speed, accuracy, precision and spectral coverage."

"The unique properties of FARS make it well suited for many existing challenges in trace gas sensing," Mr Truong wrote in a paper published online today in the journal, Nature Photonics.

"We see clear applications in the real-time measurements of greenhouse gas fluxes, as well as in the monitoring of dynamic processes such as combustion."

More information: dx.doi.org/10.1038/NPHOTON.2013.98