Science at the Shine Dome 2010

Early-career researcher awards

Thursday, 6 May 2010

Inaugural Anton Hales Medal (2009)

Professor Jeffrey Walker
Reader in Environmental Engineering, Department of Civil and Environmental Engineering, University of Melbourne.

Jeffrey Walker received his BE (Civil) and B.Surveying degrees in 1995 with first class honours and the University Medal from the University of Newcastle, Australia, and his PhD in water resources engineering from the same university in 1999. His PhD thesis was among early pioneering research on the estimation of root-zone soil moisture from remotely sensed surface soil moisture observations. He then joined NASA Goddard Space Flight Center to implement his soil moisture work globally.

In 2001 Jeffrey moved to the Department of Civil and Environmental Engineering at the University of Melbourne as lecturer, where he continued his soil moisture work, including the development of the only Australian airborne capability for simulating new satellite missions for soil moisture. In 2010 he was appointed professor in the Department of Civil Engineering at Monash University, where he is continuing this research. He is contributing to soil moisture satellite missions at both NASA and the European Space Agency.

Soil moisture on planet Earth

Although conceived about 30 years ago as part of NASA’s ‘Mission to Planet Earth’, the routine monitoring of temporal and spatial variation in the Earth’s soil moisture on a global scale is only now on the verge of becoming a reality. In November 2009 the European Space Agency launched the first satellite dedicated to the measurement of soil moisture, known as the Soil Moisture and Ocean Salinity (SMOS) mission. However, the data from this satellite need to be validated using detailed field campaign data, and techniques must be implemented to increase the spatial resolution and depth of this soil moisture information.

Using a unique airborne simulator, the pre-launch soil moisture retrieval algorithms for SMOS have been extensively tested using detailed ground measurements and airborne observations from a series of intensive field campaigns undertaken in Australian soil moisture observatories. Moreover, an extensive validation campaign has just been undertaken in the Murrumbidgee soil moisture observatory, representing a typical slice of Australia. By accurately mapping the spatial variability across an area comprising more than twenty independent SMOS pixels, this extensive airborne campaign provides not only the first but possibly also the most comprehensive validation of observed brightness temperatures and derived soil moisture from the SMOS mission. Once validated, the soil moisture monitoring information that this satellite affords will be used to constrain numerical model predictions, thus providing a real-time soil moisture monitoring and prediction capability for Australia, leading to improvements in weather prediction, flood forecasting, drought monitoring, water accounting and agricultural productivity.