A transparent method for the analysis and quality evaluation of irregulary distributed and noisy observational data
- Author(s)
- Reinhold Steinacker, Christian Häberli, Wolfgang Poettschacher
- Abstract
Observational errors may have a serious impact on objective analyses. Before conducting an objective analysis. that is, interpolating irregularly spaced observations to a uniform grid, the data should be checked thoroughly for errors. For this procedure a piecewise functional fitting approach is proposed, which is based on a variational algorithm. As for thin-plate splines, an intergral of squares of second temporal and/or spatial derivatives is minimized. The second derivatives are obtained from overlapping finite elements using a polynomial approach. In a slightly different mode, the same approach may also be used to interpolate the observational data to a regular grid. The method is formulated for and applied to scalar and vector quantities in a one- and two-dimentional domain. The basic advantages of the method are on a the hand the fact that no first guess or (prognostic) model field is necessary and on the other hand that no a priori knowledge about structure or explicitly. One of the most valuable features of the method is its simplicity. For a single station it is possible to recalculate by hand each step, which may make the procedure transparent. The comparatively inexpensive computational effort renders it especiallly well suited to model-independent quality assesment procedures and mesoscale objective analyses. It is presently used within the framework of the Mesoscale Alpine Programme.
- Organisation(s)
- Department of Meteorology and Geophysics
- External organisation(s)
- University of Vienna
- Journal
- Monthly Weather Review
- Volume
- 128
- Pages
- 2303-2316
- No. of pages
- 14
- ISSN
- 0027-0644
- DOI
- https://doi.org/10.1175/1520-0493(2000)128<2303:ATMFTA>2.0.CO;2
- Publication date
- 2000
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 1030 Physics, Astronomy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/be0261ea-4af2-4c7f-9655-2f4907140fde