Wind Erosion in Western Queensland Australia

Chapter 3 – Modelling Land Erodibility Review2001; Zender et al., 2003a). This approach is surprising considering the diverse spatial scalesat which wind erosion models have been developed to operate. It reflects difficulties inobtaining measurements of wind erosion activity over large areas, and also inherentdifficulties associated with obtaining representative measurements of a spatio-temporallydynamic process. Global scale studies of dust transport are increasingly comparing modeloutputs with remotely sensed data on aerosol optical thickness to obtain spatial assessmentsof model performance (e.g. Mahowald et al., 2003a; Ginoux et al., 2004).Validation of the model components is generally considered during their development(individually) or through validation of the complete wind erosion models (e.g. Marticorenaand Bergametti, 1995). Explicit validation of model assessments of u *t have not beenreported. This reflects the fact that, despite the potential for doing so, the models have notbeen applied to assess land erodibility.3.6 SummaryThis chapter has presented a review of approaches for representing land erodibility in winderosion models. The review has covered empirical and mechanistic models that have beenapplied to quantify soil loss and dust emission from the field to global scales. The chapter hasreviewed limitations to wind erosion modelling, including: the availability of robust modelsto predict temporal variations in soil erodibility; the availability of suitable model input data;a requirement for robust methods to upscale models and account for sub-grid scaleheterogeneity in soil and vegetation conditions; and a reliance on validating models at smallpoint scales or very coarse resolutions due to a lack of data available to test the performanceof models at intermediate (landscape to regional) scales. Most notably, and despiteconsiderable modelling efforts, there has been a significant lack of research that seeks toapply models to assess spatial and temporal patterns in the susceptibility of landscapes towind erosion. This is essential for accurately assessing spatial and temporal patterns in landerodibility, particularly in rangeland environments.Considerable effort has been directed toward scaling issues associated with broad-scalespatial modelling (see Raupach and Lu, 2004; Shao, 2000) and dealing with sub-grid scaleheterogeneity (e.g. Okin, 2008). Priority must therefore be given to addressing gaps in96