DESCRIPTION

The tool uses methods of zonal statistics to compute average values of 24 hours precipitation amounts of specified return period for a provided area or a spot. Rasters of daily maxima were derived from statistics published by Samaj et al. in 1985, which were based on precipitation series observed in 1901-1980. Calculated average value (in millimeters) is then reduced to the chosen length of design rain event.

NOTES

First automatization has been implemented by well-known method which is based on reduction of 24 hours design precipitation to shorter time. GIS can used for spatial supervised classification of point values of specified return periods (2, 10, 20, 50 and 100 years).

Figure: Basins (in orange) with orthophoto on background	Figure: Return periods (2, 10, 20, 50 years) in the area of the Czech Republic

Figure: IV.order basins colored by mean H_N2T60 value (in millimeters)

EXAMPLE

r.subdayprecip.design map=basin return_period=N2,N5,N10,N20 rainlength=60

REFERENCES

• Landa M., Kavka P., Strouhal L. (2015). A GIS tool for reduction day precipitation to subday (poster)
• Tomasu M. (2013). Tvorba nastoje pro sestaveni kratkodobych navrhovych destu na zaklade rizene interpolace a redukce (in Czech)
• Torfs, P. J. J. F., Horacek, S., & Rakovec, O. (2010). Chimera, a framework for conceptual modelling using analytical sensitives to parameters: implementation and application to PDM model.
• Sokol, Z., & Bliznak, V. (2009). Areal distribution and precipitation-altitude relationship of heavy short-term precipitation in the Czech Republic in the warm part of the year. Atmospheric Research, 94(4), 652-662.

Acknowledgement

SEE ALSO

AUTHORS

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