Pioneering ocean survey a step closer

A device to help Edinburgh scientists track atmospheric greenhouse gases will soon be installed in a NASA aircraft.

The equipment is being shipped to California to be mounted in a Global Hawk unmanned plane.

Once in situ, the instrument will measure atmospheric columns of carbon dioxide, methane and carbon monoxide over huge swaths of the Pacific Ocean.

Carbon management

Researchers hope the kit can improve their understanding of the natural carbon cycle by accurately estimating the emission and uptake of greenhouse gases.

This will help manage future levels of carbon dioxide, to support international agreements and national emission reduction programmes.

High altitude

The aircraft will be flown at altitudes up to 20,000m.

This is above the troposphere, where most of the Earth’s weather occurs.

The device on board, known as GreenHouse Observations of the Stratosphere and Troposphere - GHOST, is adapted from astronomy technology and was built at the UK Astronomy Technology Centre in Edinburgh.

Knowledge gap

The instrument plays a role in the Natural Environment Research Council (NERC) Coordinated Airborne Studies in the Tropics (CAST) project.

Scientists anticipate that the prototype instrument will provide fine-scale greenhouse gas measurements.

These will fill a measurement gap left by space-borne platforms and conventional in-situ instrumentation.

Light detection

GHOST can detect infrared light, which is absorbed by greenhouse gases, to measure atmospheric carbon dioxide, methane and carbon monoxide.

By measuring sunlight reflected from the ocean surface below, and incorporating this data into a large-scale numerical weather model, researchers can understand the atmospheric movement of gases.

It will allow scientists for the first time to observe the total amount of key gases at the same time.

The Global Hawk can fly for more than 24 hours at a time, enabling scientists to gather an unprecedented amount of information about the atmosphere.

GHOST represents a new collaboration between groups that have in the past focused on Astronomy and Earth observation, and a strategic alliance within Edinburgh, and I hope these will ultimately lead to more opportunities in the future.

Professor Paul PalmerSchool of GeoSciences