| Volumes and Issues Contents of Issue 4 |
www.geosci-model-dev-discuss.net/4/3161/2011/
doi:10.5194/gmdd-4-3161-2011
© Author(s) 2011. This work is distributed
under the Creative Commons Attribution 3.0 License.
Wavelet-based spatial comparison technique for analysing and evaluating two-dimensional geophysical model fields
Plymouth Marine Laboratory, Prospect Place, The Hoe, PL1 3DH Plymouth, UK
Abstract. Complex numerical models of the Earth's environment, based around 3-D or 4-D time and space domains are routinely used for applications including climate predictions, weather forecasts, fishery management and environmental impact assessments. Quantitatively assessing the ability of these models to accurately reproduce geographical patterns at a range of spatial and temporal scales has always been a difficult problem to address. However, this is crucial if we are to rely on these models for decision making. Satellite data are potentially the only observational dataset able to cover the large spatial domains analysed by many types of geophysical models. Consequently optical wavelength satellite data is beginning to be used to evaluate model hindcast fields of terrestrial and marine environments. However, these satellite data invariably contain regions of occluded or missing data due to clouds, further complicating or impacting on any comparisons with the model. A methodology has recently been developed to evaluate precipitation forecasts using radar observations. It allows model skill to be evaluated at a range of spatial scales and rain intensities. Here we extend the original method to allow its generic application to a range of continuous and discontinuous geophysical data fields, and therefore allowing its use with optical satellite data. This is achieved through two major improvements to the original method: (i) all thresholds are determined based on the statistical distribution of the input data, so no a priori knowledge about the model fields being analysed is required and (ii) occluded data can be analysed without impacting on the metric results. The method can be used to assess a model's ability to simulate geographical patterns over a range of spatial scales. We illustrate how the method provides a compact and concise way of visualising the degree of agreement between spatial features in two datasets. The application of the new method, its handling of bias and occlusion and the advantages of the novel method are demonstrated through analyzing model fields from a marine ecosystem model.
Discussion Paper (PDF, 3562 KB) Supplement (2 KB) Interactive Discussion (Closed, 8 Comments) Final Revised Paper (GMD)
Notice on Discussion StatusCitation: Saux Picart, S., Butenschön, M., and Shutler, J. D.: Wavelet-based spatial comparison technique for analysing and evaluating two-dimensional geophysical model fields, Geosci. Model Dev. Discuss., 4, 3161-3183, doi:10.5194/gmdd-4-3161-2011, 2011. Bibtex EndNote Reference Manager XML
