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Research Projects

Current Research Projects

Improved Rainfall Measurement Using Mobile Phone Tower Link Attenuation

Accurate near-real-time precipitation data at high resolution are critical to flash flood forecasting in and around Australia's capital cities. Current precipitation estimates suffer from the limited availability of rain gauge data in urban areas. However, mobile phone towers abound and the microwave links between them can provide information on rainfall intensity, meaning that these data may be used to supplement the shortfall in raingauge data. This project will develop the technology to generate precipitation maps using the combination of mobile phone network link, rain gauge and weather radar data. Melbourne will be the case study, validated using a research microwave scintillometer and super high resolution mobile weather radar.

Preserving Vegetation Health and Biodiversity of Natural, Urban Reserves

The aim of this project is to quantify the links between water resources, vegetation health and biodiversity in small native and remnant vegetation reserves embedded in urban environments. The specific objectives are to i) quantify water requirements and carbon balances in four reserves within Greater Melbourne hosting native tree species (River Red Gum), identified as vulnerable or endangered, and experiencing different rainfall regimes as well as water management practices, ii) test a set of measurement methods (in-situ and remote sensing) to relate water use with tree growth and biodiversity in urban reserves, and iii) develop a model for the water balance and vegetation growth to assist in the management of urban reserves and parks.

A Multi-frequency Microwave Radiometer System for Environmental Research

A multi-frequency microwave radiometer system for environmental research: A new capability for airborne remote sensing of key environmental variables will be established. The unique P-, Ku- and Ka-band passive microwave radiometer system will provide information on soil moisture, surface temperature and vegetation, and allow for a new satellite concept to be demonstrated. By combining with an existing L-band radiometer, data can be collected simultaneously at P-, L-, Ku- and Ka-bands, with increased spatial resolutions accordingly. The shorter wavelength, but higher spatial resolution data can be used to enhance the spatial resolution of the longer wavelength data, resulting in a capability to derive long wavelength observations from space at unprecedented spatial resolution.

On-the-go Soil Moisture Monitoring from GPS Signals During Routine Farming Operations

Mapping near surface soil moisture variation across agricultural fields is currently a challenging problem, especially as part of routine farming operations. Even earth observation satellites are a challenging option, due to the low spatial resolution of the most suitable satellites (several kilometres). Moreover, widely used field-based sensors only provide soil moisture measurements at single points, with many sensors required to provide a complete map. To overcome these issues, a proximal sensing technique for soil moisture mapping is proposed, which uses the ground reflected signals from Global Navigation Satellite Systems (such as the Global Positioning System) collected from tractors and other such farm equipment as they work the paddocks.

Linking Flow, Nutrients, Seagrass and Fish: An Integrated Approach to Estuary Management

Estuaries are iconic recreational areas providing both ecological habitat and millions of dollars in revenue to the tourism and fisheries industries. How estuaries respond to human pressures is highly variable with some such as the Gippsland Lakes succumbing to algal blooms, whilst other heavily nutrient laden systems such as the Werribee Estuary support extremely high fish populations. This project aims to lead to an understanding of the links between freshwater flow, blue-green algal blooms, and recruitment of a key fishery species, black bream. The outcome of the project aims to give catchment managers greater confidence in setting levels of environmental flows that will both support fish populations but also mitigate against algal blooms.

Catchment Water Balance and CO2 Fluxes: A Comparison Between Productive Land Uses

The aim of the project is to improve the understanding of different land use implications on water resource and land productivity. The project aims to use a paired-catchment study that compares the carbon and water balances in two catchments in the high rainfall zone in south western Victoria. One catchment is used prevalently for grazing, while the other is predominantly planted with blue gums. The main objectives of this project are: to quantify the effect of different agricultural land uses on the catchment water balance; to estimate the trade-off between carbon sequestration and water resources related to tree plantations and pastures; and to develop models at different spatial scales of catchment water balance for land-use management.

Validation of Global Water and Energy Balance Monitoring in the Australian Murray-Darling Basin Using GCOM-W1 Data

Together with the Japan Aerospace Exploration Agency (JAXA), this project will undertake validation of the Global Change Observation Mission for Water (GCOM-W) Advanced Microwave Scanning Radiometer-2 (AMSR-2) soil moisture observations in the Murray Darling Basin of Australia, and their subsequent use in land surface data assimilation systems. In order to validate both the AMSR-2 surface soil moisture product, and the derived root-zone soil moisture and land surface flux exchange through assimilation into land surface models, long-term ground observation of flux data will be collected within the SMAP Test-bed focus site, which is appropriately sized for the AMSR-2 footprint.

Improving Flood Forecasting Skill Using Remote Sensing Data

The hypothesis of this project is that remote sensing can be a very helpful tool for operational water management, with a particular focus on flood forecasting. For this purpose, remote sensing data will be used in two different ways. First, estimated soil moisture profiles from hydrologic models will be improved through the merging of these model predictions with remotely sensed surface soil moisture values. This is expected to have a beneficial impact on modelled hydrographs. Second, estimated flood inundations and water levels from hydraulic models will be improved through merging these model results with remotely sensed observations of flood inundations or water levels. This is expected to improve the predictive capability of the hydraulic model. Overall, using remote sensing data in flood forecasting is expected to lead to better early warning systems, management of floods, and post-processing of flood damages. The objective of the project is to demonstrate the utility of coupled hydrologic/hydraulic model forecasting and data assimilation using remotely sensed data for potential operational use. This is expected to have a strong future beneficial impact on flood management practices in Australia.

MoistureMonitor: A Multi-mission Soil Moisture Monitoring System for a Water Limited Future

A long-term soil moisture record for Australia is critical to understanding climate change feedback mechanisms and their impacts on water management. This project will validate, downscale and harmonise soil moisture retrievals from three satellite missions across this decade, each using a new and different low resolution antenna technology and interpretation approach. MoistureMonitor, the framework to deliver this soil moisture record, will be verified using airborne campaigns and hydrological monitoring infrastructure in the Murrumbidgee catchment. Important outcomes will be validation of a new soil moisture satellite and development of a high resolution soil moisture product for improved land and water management and policy for Australia.

Mobile Weather Radar System for Advanced Environmental Monitoring and Modelling

The proposed infrastructure seeks to establish a new national capability for high spatial and temporal resolution weather radar data acquisition with application to a range of environmental fields. The METEOR 50DX is an X-Band weather radar system featuring Doppler and dual polarization technology to provide Australian rainfall and wind information with unprecedented accuracy and detail. Its compact trailer mounted design makes it suitable for applications across Australia, thus complementing our sparse national weather radar network, which is limited by the quality and coverage of many of its current radars. This new capability will allow Australian researchers to undertake world-class research on environmental prediction hitherto impossible.

SMOS + Hydrology

The integration of low resolution SMOS observations into finer resolution hydrologic models poses significant challenges. Therefore, this study aims at developing a robust end-to-end methodology that allows for the assimilation of SMOS data (either brightness temperature or soil moisture) into land surface models and for assessing the usefulness of SMOS data with respect to flood forecasting. The assimilation system is being set up for the Variable Infiltration Capacity (VIC) land surface model coupled to a river routing scheme, and tested for two large river basins, the Upper Mississippi Basin in central USA and the Murray Darling Basin in Eastern Australia. The aim of the study is to demonstrate the potential and limits of the SMOS level 1 and level 2 products and their benefits for flood prediction.

Past Research Projects

Towards Global Water and Energy Balance Monitoring Using GCOM-W1 in the Australian Murray-Darling Basin

Together with the Japan Aerospace Exploration Agency (JAXA), this project will undertake validation of the Global Change Observation Mission for Water (GCOM-W) Advanced Microwave Scanning Radiometer-2 (AMSR-2) soil moisture observations in the Murray Darling Basin of Australia, and their subsequent use in land surface data assimilation systems. In order to validate both the AMSR-2 surface soil moisture product, and the derived root-zone soil moisture and land surface flux exchange through assimilation into land surface models, long-term ground observation of flux data will be collected within the SMAP Test-bed focus site, which is appropriately sized for the AMSR-2 footprint.

A New Generation Flood Forecasting System Using Observations From Space

Working with the Bureau of Meteorology, US Department of Agriculture Hydrology and Remote Sensing Laboratory and CSIRO, this project will develop a novel approach to combine observational data and computer models using data assimilation techniques to substantially improve the Bureau of Meteorology's flood forecasting system. Current flood forecasts have a number of error sources that reduce their accuracy. We will integrate satellite observations of soil moisture and rainfall into the Bureau's flood forecasting model to improve the accuracy of forecasts by reducing errors in rainfall inputs and modelled catchment wetness. The success of this study will result in a more accurate flood warning system for Australia.

Towards Operational Monitoring of Key Climate Parameters from Synthetic Aperture Radar

Economic, social, and environmental planning for a carbon-constrained future requires a capacity to monitor climate change impacts on vegetation and soil moisture at a level of detail that does not currently exist. While radar measurements from satellites can provide this important information, the signals are confounded by complex interactions with the Earth surface. Specifically, terrain micro-topography, vegetation structure/biomass, and the underlying soil moisture status, all interact together in an intricate way. Using airborne radar data together with detailed ground measurements, models of this complex interaction will be developed and tested for subsequent time-series application to satellite data across Australia.

Active Passive Microwave Soil Moisture Remote Sensing: Towards Sustainable Land and Water Management From Space

Soil moisture is a highly critical resource for the Australian agricultural economy which is stressed by climate change. Daily monitoring of paddock scale soil moisture from space represents a powerful tool to inform land management, allowing accurate crop yield and pasture growth predictions. At the continental scale, soil moisture information will result in better weather, climate and extreme flood prediction skill and the ability to assess the effects of future climate change on Australia. It is therefore imperative that active passive soil moisture retrieval algorithms be developed specifically for the Australian environment in order to take full advantage of the SMAP remote sensing mission when it is launched in 2012.

A New Paradigm for Improved Water Resource Management Using Innovative Water Modelling Techniques

The threat of climate change and Australia's arid environment makes accurate water resource planning essential for sustainable water management. This is particularly relevant in rural Australian catchments with competing needs for scarce water resources, including irrigation to sustain farming communities, maintaining adequate flows for river health, and seasonal flooding for fragile eco systems. Accurately predicting key water balance components across catchments is crucial for improved water resource planning. Continuously constraining model predictions with time series of spatial data can identify weaknesses in model physics for correction and make model scenario testing more reliable so better water management decisions can be made.

MoistureMap: A Soil Moisture Monitoring, Prediction and Reporting System for Sustainable Land and Water Management

Knowledge of the spatial and temporal variation of surface and root zone soil moisture content is critical to environmental sustainability and risk adverse farm management. A paddock scale soil moisture prediction tool will allow i) grain growers to make informed decisions of what to plant and when, based on likely germination rates and crop yield, ii) graziers to be proactive regarding management of stocking rates based on likely pasture growth, and iii) better weather and climate prediction skill. At regional scales moisture information can be used to support claims of drought exceptional circumstances.

Quantifying Near-surface Diffuse Discharge from the Southwest Great Artesian Basin

The Great Artesian Basin (GAB) is the largest groundwater resource in Australia and supports a number of mining and pastoral operations. Sustainable use of this resource requires an improved understanding of its water balance, particularly the large component of vertical leakage. This project proposes to use isotopic and geochemical techniques, in addition to physical monitoring of evaporation losses, to constrain the near-surface component of vertical leakage from the GAB in South Australia. Sampling will be optimally targeted and scaled up using detailed mapping of the near-surface leakage zones from remote sensing. This study will result in improved understanding and management of this critical resource.

Airborne Hyperspectral Scanning for Advanced Monitoring and Assessment of Vegetation and Water Properties

The proposed infrastructure will give Australian researchers the most advanced capabilities available world wide in airborne remote sensing of the environment. By combining hyper spectral scanning, with full wave form resolving Light Detection and Ranging (LIDAR), microwave scanning and sythetic aperture RADAR, flown simultaneously on the most cost efficient and technologically advanced research aircraft, it will be possible to assess and monitor a wide range of parameters not accessible to airborne methods before.

Towards Improved Soil Moisture Retrieval by LiDAR Measurement of Microwave Properties of Vegetation and Development of a Data Assimilation Framework

We aim to improve the accuracy of soil moisture retrieval from satellite-based passive microwave systems. First, data collected from the recent Australian National Airborne Field Experiments (NAFE) by the University of Melbourne will be used to evaluate and test the data assimilation framework developed at the University of Reading (for snow mass modelling) in the context of soil moisture retrieval. Second, techniques used at the University of Reading for deriving vegetation structural information from airborne scanning LiDAR will be developed for application to a wider range of vegetation types and larger spatial scales, and applied to the NAFE data sets to explore the effects of improved vegetation characteristics on the retrieval of soil moisture from passive microwave observations.

High Resolution Airborne Radar for Environmental Research: Soil Moisture, Vegetation, Salinity and Terrain Mapping

There is a rapidly increasing demand for a range of environmental data. For example, information on soil moisture status is required for efficient and sustainable water use. Moreover, irrigation practices and large scale clearing have led to serious land degradation through increased salinity from rising water tables. Combined soil moisture and salinity measurement will provide important insight to this complex issue. Further, understanding the complex and rich biodiversity of Australian flora and its adaptation to droughts and fire is essential to ensuring Australian ecosystem longevity. Knowledge of flora changes through time as a function of soil moisture content and salinity is key to gaining this understanding.

Potential Applications for Airborne Remote Sensed Data This project investigates the potential for high-resolution airborne sensing technologies for monitoring human impacts on rivers at the basin-scale. The resolution and coverage provided by airborne data can potentially transform our understanding of landscape-scale impacts and underlying causal processes. Improved monitoring and understanding of these impacts will inform more effective environmental policy and management for rivers at regional, state and national levels.

The Murrumbidgee Monitoring Network

This project will make the Murrumbidgee Monitoring Network data available to the ACCESS modelling community.

Improving the Airborne Mapping of Soil Moisture

Deriving soil moisture from passive microwave observations requires knowledge of the near surface soil temperature. The aim of our project is to develop a model by which the near surface soil temperature can be estimated from airborne data. These estimates can then be used for the retrieval of soil moisture information.

Airborne Laser Scanning for Advanced Environmental Monitoring

This proposal seeks to enhance the national capability for airborne remote sensing of key environmental variables through the acquisition of an airborne laser scanner and inertial navigation system. Many environmental science studies, such as hydrology, soil moisture scaling and salinity, can be significantly enhanced by airborne laser scanning, through the creation of high precision, high resolution digital terrain models. Airborne laser scanning can also measure three dimensional vegetation canopy structure, a useful indicator of biomass, carbon storage and vegetation health. This infrastructure will provide Australian researchers with a unique arsenal of remote sensing tools for advanced yet affordable environmental research Studies.

Advanced Algorithms to Retrieve Remotely Sensed Soil Moisture and Enhance Hydrological Prediction

The spatial information on soil moisture provided by remotely sensed data has considerable potential to improve hydrological prediction. Despite this, it has had very little application in hydrological modelling. This is because remote sensed data is an indirect measure of soil moisture, confounded by several factors which introduce considerable uncertainties. These uncertainties have proved difficult to reliably characterise and this has limited application. This project will utilise unique datasets acquired in recent large scale field experiments to develop new algorithms to more accurately retrieve remotely sensed soil moisture and its associated uncertainty. These algorithms will be based on statistical Bayesian hierarchal spatio-temporal models which have yet to be applied to retrieving soil moisture from remotely sensed data. The potential of new algorithms to improve the predictive power of hydrological models will be assessed. This pilot project will develop prototype algorithms on a small scale to demonstrate proof-of-concept with the long-term goal of seeking external research funding to develop a large scale application.

Integrate NASA's Global Soil Moisture Remote Sensing and Modeling Data into USDA's Global Crop Production Decision Support System

This project aims at integrating NASA?s global soil moisture remote sensing and modeling data products into the U. S. Department of Agriculture?s Global Crop Production Decision Support System to improve their reliability and accuracy for forecasting crop yields. USDA?s crop yield forecasts affect decisions made by farmers, businesses, and governments by defining the fundamental conditions in commodity markets.

High Resolution Mapping of Surface and Root Zone Soil Moisture

Knowledge of the spatial and temporal variation of surface and root zone soil moisture content at high spatial resolution is critical to achieving more efficient water utilisation practices in agriculture. Australia 's main river basins are under mounting pressure to satisfy a wide range of competing economic, social and environmental needs for water, particularly in terms of environmental flows and efficient irrigation. A better understanding of the soil moisture distribution at sub-farm scales will allow farmers to better utilise both the moisture in their soil and their limited allocation for irrigation. This will help alleviate soil moisture related problems in some of the nation's key catchments, such as the Murray Darling Basin.

Assimilation of Latent and Sensible Heat Flux Data into the CSIRO Biosphere Model

This project will investigate the use of latent and sensible heat flux data to improve the predictive performance of a land surface model. The significance of land surface models is their ability to provide continuous prediction of latent and sensible heat flux feedback to atmospheric models for weather and climate forecasting. Historically, soil moisture and/or air temperature and humidity data have been used to correct land surface model predictions, despite their often weak and indirect relationship to latent and sensible heat flux. This research aims to use direct information on latent and sensible heat flux to achieve optimal flux predictions from land surface models.

Gravity Changes, Soil Moisture and Data Assimilation

This project will assess the utility of space and ground-based gravity measurements for monitoring changes in the hydrological cycle at regional scales. At present there are no methods available for monitoring changes in terrestrial water storage over the globe, despite its importance for assessing the effects of large-scale changes in land use and climate change. The launch of NASA's Gravity Recovery and Climate Experiment (GRACE) satellites earlier this year provides a 5-year window of opportunity to undertake ground-based research to test this innovative technique for monitoring terrestrial water storage from gravity measurements - something that has been shown to be possible theoretically, but has not been testable until now.

On the Use of Remote Sensing Data in Bio-geo-chemical Marine Models

This project will investigate the use of satellite and other sources of water quality data for evaluating coastal marine model structure and improving predictive performance. The capability to model highly complex bio-geo-chemical marine systems is becoming increasingly possible due to advances in computing power, remote sensing data availability and interpretation algorithms. However, the techniques for using this data to evaluate and/or correct model trajectories are immature. This project will enhance the current capacity for using satellite derived data sources in marine bio-geo-chemical models with the purpose of generating greater credibility and reliability of model predictions. It will combine the strengths of CSIRO marine modelling capability with the UofM?s expertise in data assimilation and spatial analysis.

A New Airborne Facility for Environmental, Hydrological, Atmospheric and Oceanic Research: High Resolution Measurement of Soil Moisture, Temperature and Salinity

This proposal seeks to establish a new national capability for airborne remote sensing of key environmental variables. It will enable high-resolution mapping of near-surface soil moisture, land surface salinity and temperature, and ocean surface salinity and temperature. It will be a new tool for hydrologic, atmospheric and oceanic researchers, providing unprecedented detail on characteristics critical to our understanding and management of the environment. The small instrument size and weight will enable use of a light aircraft as the observing platform, providing the national (and international) research community with an affordable tool, hitherto unavailable.

Scaling and Assimilation of Soil Moisture and Streamflow

Information on how soil moisture varies in space and time has been largely restricted to point-scale groundbased measurements. We will develop methods for predicting how soil moisture status evolves in time over a range of spatial scales, by assimilating groundbased measurements and satellite observations of soil moisture together with streamflow observations into simple rainfall-runoff models. Extensive soil moisture monitoring will allow development of scaling relationships and validation for new satellite-based microwave radiometers.

Use of Remote Sensing Actual Evapotranspiration Estimates and Water Delivery Data for Assessing Water Use Efficiency in an Irrigated Landscape

Improving management of water in irrigated agriculture will lead to increased sustainability, decreased environmental impacts and increased profitability. Quatifying water use efficiency for an irriguation district is a vital part of improving water management. This project aims to develop new methods for quatifying water use efficiency by combining actual evapotranspiration estimates with water delivery information at the farm scale for an entire irrigation district. Remote sensing techniques will be utilized to map actual evapotranspiration and water meter data will be combined with cadastral and channel network data to map water delivery.

Assimilation of Satellite Observations of the Land Surface in Support of NASA's Seasonal-to-Interannual Prediction Project

This project will address the importance of assimilation of satellite observations, with the focus on soil moisture retrievals, in the initialisation of the land surface to enhance seasonal-to-interannual climate forecasts. Key aspects of this research are i) the extension of the current one-dimensional approach to take into account three-dimensionsl structures in forecast error due to forcing error and large scale correlations in the model properties; and through the development of strategies to account for model biases, and ii) the implementation of an operational land assimilation system based on these combined activities.

A Catchment-Based Global River Routing Scheme for Climate Models and Assimilation of Streamflow and Altimetry Data

There are two broad goals of this research. The first is to develop and test a new, catchment-based, global river transport scheme for use in global climate models and coupled climate system models that overcomes the shortcommings of cell-based models. The second goal is to develop and test methodologies for assimilation of stream gauge and satellite altimetric measurements into the new scheme.

Global Validation of EOS-AQUA Land Surface Dynamics Using Data Assimilation

This project seeks to determine the nature and variability in selected global soil moisture and snow products measured by the AMSR-E sensor on a variety of time scales, and to analyise the effects of these uncertainties on the predictability of the global surface water and energy balance using land surface data assimilation techniques in near real-time.

Optimal Land Initialisation for Seasonal Climate Prediction

This project seeks to provide optimal initialisation of the NSIPP (NASA Seasonal to Interannual Prediction Project) land surface model, through assimilation of near-surface soil moisture observations into the land surface model.

Validation of the AMSR-E Satellite Soil Moisture Product

One of the products to be provided by the AMSR-E remote sensing instrument is 25km resolution near-surface (top 1cm) soil moisture content at a specified accuracy of better than 6%v/v for areas having vegetation cover of less than 1.5kg/m2. Due to a lack of historical data, the algorithms to derive this soil moisture product have not been widely tested. We propose to test the validity of these algorithms for soil moisture measurement under Australian conditions.

Optimal Land Initialisation for Seasonal Climate Prediction: Brightness Temperature Assimilation

Accurate initialisation of the land surface in global climate models is critical for seasonal-to-interannual climatological prediction, because of its regulation on fluxes from the land surface to the atmosphere. Previous work has demonstrated the ability to obtain soil moisture initial conditions throughout the top metre or so of the Earth?s surface by assimilation of satellite measurements of near-surface soil moisture. This project seeks to extend that work, by assimilating the satellite brightness temperature measurements (ie. measurements of the radiation received at the sensor), rather than a derived soil moisture product, allowing the assimilation to impact both the soil moisture and temperature states, and eliminating restrictive assumptions made in deriving the soil moisture independent of the assimilation.

Optimal Land Initialisation for Seasonal Climate Prediction: Soil Moisture Assimilation

Accurate initialisation of the land surface in global climate models is critical for seasonal-to-interannual climatological prediction, because of its regulation on fluxes from the land surface to the atmosphere. Due to its long term persistence, it is most important that land soil moisture content be optimaly initialised. This project seeks to provide optimal land surface initialisation for Australia, in collaboration with the NASA Seasonal-to-Interannual Prediction Project (NSIPP) and the efforts at NASA Goddard Space Flight Centre to provide such initial conditions globally, through the assimilation of satellite measurements of near-surface soil moisture.

Assimilation of Remotely Sensed Snow Observations into the NSIPP Land Surface Model

This project seeks to provide optimal initialisation of the NSIPP (NASA Seasonal to Interannual Prediction Project) land surface model, through assimilation of snow melt signature, snow water equivalent, snow depth and snow cover observations into the land surface model.

A Global Land Data Assimilation System (GLDAS)

This project seeks to develop a high resolution, near-real-time global land data assimilation system using relevant remotely sensed and in-situ observations within a land data assimilation framework. This project is an extension to the North American LDAS project.