<?xml version="1.0" encoding="utf-8" standalone="no"?>
<!DOCTYPE article SYSTEM "http://www.hydrol-earth-syst-sci.net/inc/hess/copernicus.dtd">
<article language="en">
	<journal>
		<journal_title>Hydrology and Earth System Sciences</journal_title>
		<journal_url>www.hydrol-earth-syst-sci.net</journal_url>
		<issn>1027-5606</issn>
		<eissn>1607-7938</eissn>
		<volume_number>13</volume_number>
		<issue_number>10</issue_number>
		<publication_year>2009</publication_year>
	</journal>
	<doi>10.5194/hess-13-1907-2009</doi>
	<article_url>http://www.hydrol-earth-syst-sci.net/13/1907/2009/</article_url>
	<abstract_html>http://www.hydrol-earth-syst-sci.net/13/1907/2009/hess-13-1907-2009.html</abstract_html>
	<fulltext_pdf>http://www.hydrol-earth-syst-sci.net/13/1907/2009/hess-13-1907-2009.pdf</fulltext_pdf>
	<start_page>1907</start_page>
	<end_page>1920</end_page>
	<publication_date>2009-10-19</publication_date>
	<article_title content_type="html">Mapping rainfall erosivity at a regional scale: a comparison of interpolation methods in the Ebro Basin (NE Spain)</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>M. Angulo-MartÃ­nez</name>
		</author>
		<author numeration="2" affiliations="3">
			<name>M. LÃ³pez-Vicente</name>
		</author>
		<author numeration="3" affiliations="2">
			<name>S. M. Vicente-Serrano</name>
		</author>
		<author numeration="4" affiliations="1">
			<name>S. BeguerÃ­a</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Department of Soil and Water, Aula Dei Experimental Station â€“ CSIC, 1005 Avda. MontaÃ±ana, 50080-Zaragoza, Spain</affiliation>
		<affiliation numeration="2" content_type="html">Department of Geo-environmental Processes and Global Change, Pyrenean Institute of Ecology â€“ CSIC, 1005 Avda. MontaÃ±ana, 50080-Zaragoza, Spain</affiliation>
		<affiliation numeration="3" content_type="html">Department of Earth and Environmental Sciences, Katholieke Universiteit Leuven, Celestijnenlaan 200E, 3001 Leuven-Heverlee, Belgium</affiliation>
	</affiliations>
	<abstract content_type="html">Rainfall erosivity is a major causal factor of soil erosion, and it is
included in many prediction models. Maps of rainfall erosivity indices are
required for assessing soil erosion at the regional scale. In this study a
comparison is made between several techniques for mapping the rainfall
erosivity indices: i) the RUSLE R factor and ii) the average EI&lt;sub&gt;30&lt;/sub&gt; index
of the erosive events over the Ebro basin (NE Spain). A spatially dense
precipitation data base with a high temporal resolution (15 min) was used.
Global, local and geostatistical interpolation techniques were employed to
produce maps of the rainfall erosivity indices, as well as mixed methods. To
determine the reliability of the maps several goodness-of-fit and error
statistics were computed, using a cross-validation scheme, as well as the
uncertainty of the predictions, modeled by Gaussian geostatistical
simulation. All methods were able to capture the general spatial pattern of
both erosivity indices. The semivariogram analysis revealed that spatial
autocorrelation only affected at distances of ~15 km around the
observatories. Therefore, local interpolation techniques tended to be better
overall considering the validation statistics. All models showed high
uncertainty, caused by the high variability of rainfall erosivity indices
both in time and space, what stresses the importance of having long data
series with a dense spatial coverage.</abstract>
	<references>
		<reference numeration="1" content_type="text"> Ahmed, S. and De Marsily, G.: Comparison of geostatistical methods for estimating transmissivity using data on transmissivity and specific capacity, Water Resour. Res., 23, 1717â€“1737, 1987. </reference>
		<reference numeration="2" content_type="text"> Arnoldus, H. M. J.: Methodology used to determine the maximum potential average annual soil loss due to sheet and rill erosion in Morocco, FAO Soils Bulletin, 34, 39â€“51, 1977. </reference>
		<reference numeration="3" content_type="text"> BeguerÃ­a, S. and Vicente-Serrano, S. M.: Mapping the hazard of extreme rainfall by peaks over threshold extreme value analysis and spatial regression techniques, J. Appl. Meteorol., 45, 108â€“124, 2006. </reference>
		<reference numeration="4" content_type="text"> BeguerÃ­a, S., Vicente-Serrano, S. M., LÃ³pez-Moreno, J. I., and GarcÃ­a-Ruiz, J. M.: Annual and seasonal mapping of peak intensity, magnitude and duration of extreme precipitation events across a climatic gradient, North-east Iberian Peninsula, Int. J. Climatol., 29(12), 1759â€“1779, doi:10.1002/joc.1808, 2009. </reference>
		<reference numeration="5" content_type="text"> BeguerÃ­a, S. and Pueyo, Y.: A comparison of simultaneous autoregressive and generalized least squares models for dealing with spatial autocorrelation, Global Ecol. Biogeogr., 18(3), 273â€“279, 2009. </reference>
		<reference numeration="6" content_type="text"> Boellstorff, D. and Benito, G.: Impacts of set-aside policy on the risk of soil erosion in central Spain, Agr. Ecosyst. Environ., 107, 231â€“243, 2005. </reference>
		<reference numeration="7" content_type="text"> Borrough, P. A. and McDonnell, R. A.: Principles of geographical information systems, Oxford University Press, 1998. </reference>
		<reference numeration="8" content_type="text"> Brown, D. P. and Comrie, A. C.: Spatial modelling of winter temperature and precipitation in Arizona and New Mexico, USA, Climate Res., 22, 115â€“128, 2002. </reference>
		<reference numeration="9" content_type="text"> Brown, L. C. and Foster, G. R.: Storm erosivity using idealized intensity distributions, T ASAE, 30, 379â€“386, 1987. </reference>
		<reference numeration="10" content_type="text"> Casas, M. C., Herrero, M., Ninyerola, M., Pons, X., RodrÃ­guez, R., Rius, A., and RedaÃ±o, A.: Analysis and objective mapping of extreme daily rainfall in Catalonia, Int. J. Climatol., 27, 399â€“409, 2007. </reference>
		<reference numeration="11" content_type="text"> Chiles, J. and Delfiner, P.: Geostatistics: modelling spatial uncertainty, Wiley, New York, 1999. </reference>
		<reference numeration="12" content_type="text"> Cressie, N. A. C.: Statistics for spatial data, rev. edn., John Wiley and Sons, 1993. </reference>
		<reference numeration="13" content_type="text"> Creus, J.: Las sequÃ­as en el valle del Ebro, in: Causas y consecuencias de las sequÃ­as en EspaÃ±a, edited by: Gil, A. and Morales, A., Universidad D&apos;Alacant, 231â€“259, 2001. </reference>
		<reference numeration="14" content_type="text"> Cuadrat, J. M.: Las sequÃ­as en el valle del Ebro. Aspectos climÃ¡ticos y consecuencias econÃ³micas, Rev. Real Acad. Ciencias, 85, 537â€“545, 1991. </reference>
		<reference numeration="15" content_type="text"> Curse, R., Flanagan, J., Frankenberger, B., Gelder, D., Herzmann, D., James, D., Krajenski, W., Kraszewski, M., Laflen, J., Opsomer, J., and Todey, D.: Daily estimates of rainfall, water runoff and soil erosion in Iowa, J. Soil Water Conserv., 61, 191â€“199, 2006. </reference>
		<reference numeration="16" content_type="text"> Daly, C., Gibson, W. P., Taylor, G. H., Johnson, G. L., and Pasteris, P.: A knowledge-based approach to the statistical mapping of climate, Climate Res., 22, 99â€“113, 2002. </reference>
		<reference numeration="17" content_type="text"> Deutsch, C. V. and Journel, A. G.: Gslib: Geostatistical software library and user&apos;s guide, Oxford university press, 1998. </reference>
		<reference numeration="18" content_type="text"> Diggle, P. J., Ribero, P. J., an dCristensen, O. F.: An introduction to model basis geostatistics, in: Spatial statistics and computational methods. Lecture notes in statistics, edited by: MÃ¸ller, J., Springer-Verlag, New York, 2002. </reference>
		<reference numeration="19" content_type="text"> Diodato, N.: Estimating RUSLE’s rainfall factor in the part of Italy with a Mediterranean rainfall regime, Hydrol. Earth Syst. Sci., 8, 103â€“107, 2004. </reference>
		<reference numeration="20" content_type="text"> Dirks, K. N., Hay, J. E., Stow, C. D., and Harris D.: High-resolution studies of rainfall on Norfolk Island. Part II: Interpolation of rainfall data, J. Hydrol., 208, 187â€“193, 1998. </reference>
		<reference numeration="21" content_type="text"> DomÃ­nguez-Romero, L., Ayuso MuÃ±oz, J. L., and GarcÃ­a MarÃ­n, A. P.: Annual distribution of rainfall erosivity in western Andalusia, southern Spain, J. Soil Water Conserv., 62, 390â€“401, 2007. </reference>
		<reference numeration="22" content_type="text"> Dunkerley, D.: Rain event properties in nature and in rainfall simulation experiments: a comparative review with recommendations for increasingly systematic study and reporting, Hydrol. Process., 22(22), 4415â€“4435, doi:10.1002/hyp.7045, 2008. </reference>
		<reference numeration="23" content_type="text"> Efron, B. and Tibshirani, R. J.: Improvements on cross-validation: the .632+ bootstrap method, J. Am. Stat. Assoc., 92, 548â€“560, 1997. </reference>
		<reference numeration="24" content_type="text"> GarcÃ­a-Ruiz, J. M., ArnÃ¡ez, J., White, S. M., Lorente, A., and BeguerÃ­a, S.: Uncertainty assessment in the predition of extreme rainfall events: an example from the Central Spanish Pyrenees, Hydrol. Process., 14, 887â€“898, 2000. </reference>
		<reference numeration="25" content_type="text"> Garrido, J. and GarcÃ­a, J. A.: Periodic signals in Spanish monthly precipitation data, Theor. Appl. Climatol., 45, 97â€“106, 1992. </reference>
		<reference numeration="26" content_type="text"> Gobin, A., Jones, R., Kirkby, M., Campling, P., Govers, G., Kosmas, C., and Gentile, A. R.: Indicators for pan-European assessment and monitoring of soil erosion by water, Environ. Sci. Policy, 7, 25â€“38, 2004. </reference>
		<reference numeration="27" content_type="text"> GonzÃ¡lez-Hidalgo, J. C., PeÃ±a-MonnÃ¨, J. L., and de Luis, M.: A review of daily soil erosion in western Mediterranean areas, Catena, 71, 193â€“199, 2007. </reference>
		<reference numeration="28" content_type="text"> Goodale, C. L., Aber, J. D., and Ollinger, S. V.: Mapping monthly precipitation, temperature and solar radiation from Ireland with polynomial regression and a digital elevation model, Climate Res., 10, 35â€“49, 1998. </reference>
		<reference numeration="29" content_type="text"> Goovaerts, P.: Geostatistics for natural resources evaluation, Oxford University Press, New York, 1997. </reference>
		<reference numeration="30" content_type="text"> Goovaerts, P.: Using elevation to aid the geostatistical mapping of rainfall erosivity, Catena, 34, 227â€“242, 1999. </reference>
		<reference numeration="31" content_type="text"> Goovaerts, P.: Geostatistical modelling of uncertainty in soil science, Geoderma, 103, 3â€“26, 2001. </reference>
		<reference numeration="32" content_type="text"> Hengl, T., Heuvelink, G. B. M., and Stain, A.: A gereric framework for spatial prediction of soil variables based on regression-kriging, Geoderma, 120, 75â€“93, 2004. </reference>
		<reference numeration="33" content_type="text"> Hoyos, N., Waylen, P. R., and Jaramillo, A.: Seasonal and spatial patterns of erosivity in a tropical watershed of the Colombian Andes, J. Hydrol., 314, 177â€“191, 2005. </reference>
		<reference numeration="34" content_type="text"> Hudson, N.: Soil Conservation, Cornell University Press, Ithaca, 1971. </reference>
		<reference numeration="35" content_type="text"> Kinnell, P. I. A. and Risse, L. M.: USLE-M: Empirical modelling rainfall erosion through runoff and sediment concentration, Soil Sci. Soc. Am. J., 62, 1667â€“1672, 1998. </reference>
		<reference numeration="36" content_type="text"> ICONA: Agresividad de la lluvia en EspaÃ±a. Valores del factor R de la EcuaciÃ³n Universal de PÃ©rdida de Suelo, Ministerio de Agricultura, pesca y alimentaciÃ³n, EspaÃ±a, 1988. </reference>
		<reference numeration="37" content_type="text"> Isaaks, E. H. and Strivastava, R. M.: An introduction to applied geostatistics, Oxford University Press, Oxford, 1989. </reference>
		<reference numeration="38" content_type="text"> Lal, R.: Soil erosion on alfisols in Western Nigeria. III â€“ Effects of rainfall characteristics, Geoderma, 16, 389â€“401, 1976. </reference>
		<reference numeration="39" content_type="text"> Lana, X. and BurgueÃ±o, A.: Spatial and temporal characterization of annual extreme droughts in catalonia (Northeast Spain), Int. J. Climatol., 18, 93â€“110, 1998. </reference>
		<reference numeration="40" content_type="text"> Lasanta, T.: GestiÃ³n agrÃ­cola y erosiÃ³n del suelo en la cuenca del Ebro: el estado de la cuestiÃ³n, ZubÃ­a, 21, 76â€“96, 2003. </reference>
		<reference numeration="41" content_type="text"> Llasat, M. C. and Puigcerver, M.: Meteorological factors associated with floods in the north-eastern part of the Iberian Peninsula, Nat. Hazards, 5, 133â€“151, 1994. </reference>
		<reference numeration="42" content_type="text"> Llasat, M. C.: An objective classification of rainfall events on the basis of their convective features: Application to rainfall intensity in the northeast of Spain, Int. J. Climatol., 21, 1385â€“1400, 2001. </reference>
		<reference numeration="43" content_type="text"> Leek, R. and Olsen, P.: Modelling climatic erosivity as a factor for soil erosion in Denmark: changes and temporal trends, Soil Use Manage., 16, 61â€“65, 2000. </reference>
		<reference numeration="44" content_type="text"> Lim, K. J., Sagong, M., Engel, B. A., Tang, Z., Choi, J., and Kim, K.: GIS-based sediment assessment tool, Catena, 64, 61â€“80, 2005. </reference>
		<reference numeration="45" content_type="text"> LÃ³pez-Vicente, M., Navas, A., and MachÃ­n, J.: Identifying erosive periods by using RUSLE factors in mountain fields of the Central Spanish Pyrenees, Hydrol. Earth Syst. Sci., 12, 523â€“535, 2008. </reference>
		<reference numeration="46" content_type="text"> MartÃ­n-Vide, J.: Diez caracterÃ­sticas de la pluviometrÃ­a espaÃ±ola decisivas en el control de la demanda y el uso del agua, BoletÃ­n de la AGE, 18, 9â€“16, 1994. </reference>
		<reference numeration="47" content_type="text"> McBratney, A. B. and Webster, R.: Chosing functions for semi-variograms of soil properties and fitting them to sampling estimates, J. Soil Sci., 37(4), 617â€“639, 1986. </reference>
		<reference numeration="48" content_type="text"> McBratney, A., MendoÃ§a-Santos, M., and Minasny, B.: On digital soil mapping, Geoderma, 117, 3â€“52, 2003. </reference>
		<reference numeration="49" content_type="text"> Millward, A. A. and Mersey, J. E.: Adapting the RUSLE to model soil erosion potential in a mountainous tropical watershed, Catena, 38, 109â€“129, 1999. </reference>
		<reference numeration="50" content_type="text"> Mitasova, H., Mitas, L., Brown, W. M., Gerdes, D. P., Kosinovsky, I., and Baker, T.: Modelling spatially and temporally distributed phenomena: new methods and tools for GRASS GIS, Int. J. Geogr. Inf. Syst., 9, 433â€“446, 1995. </reference>
		<reference numeration="51" content_type="text"> Mutua, B. M., Klik, A., and Loiskandl, W.: Modeling soil erosion and sediment yield at a catchment scale: the case of masinga catchment, Kenya, Land Degrad. Dev., 17, 557â€“570, 2006. </reference>
		<reference numeration="52" content_type="text"> Ninyerola, M., Pons, X., and Roure, J. M.: A methodological approach of climatological modelling of air temperature and precipitation through GIS techniques, Int. J. Climatol., 20, 1823â€“1841, 2000. </reference>
		<reference numeration="53" content_type="text"> Ninyerola, M., Pons, X., and Roure, J. M.: Monthly precipitation mapping of the Iberian Peninsula using spatial interpolation tools implemented in a Geographic Information System, Theor. Appl. Climatol., 89, 195â€“209, 2007. </reference>
		<reference numeration="54" content_type="text"> Ninyerola, M., Pons, X., and Roure, J. M.: Objective air temperature mapping for the Iberian Peninsula using spatial interpolation and GIS, Int. J. Climatol., 27, 1231â€“1242, 2007. </reference>
		<reference numeration="55" content_type="text"> Odeh, I. O. A., McBratney, A. B., and Chittleborough, D. J.: Spatial prediction of soil properties from landform attributes derived from a digital elevation model, Geoderma, 63, 197â€“214, 1994. </reference>
		<reference numeration="56" content_type="text"> Odeh, I. O. A., McBratney, A. B., and Chittleborough, D. J.: Further results on prediction of soil properties from terrain attributes: heterotopic cokriging and regression-kriging, Geoderma, 67(3â€“4), 215â€“226, 1995. </reference>
		<reference numeration="57" content_type="text"> Onori, F., De Bonis, P., and Grauso, S.: Soil erosion prediction at the basin scale using the revised universal soil loss equation (RUSLE) in a catchment of Sicily (southern Italy), Environ. Geol., 50(8), 1129â€“1140, doi:10.1007/S00254-006-0286-1, 2006. </reference>
		<reference numeration="58" content_type="text"> PeÃ±arrocha, D., Estrela, M. J., and MillÃ¡n, M.: Classification of daily rainfall patterns in a Mediterranean area with extreme intensity levels: the Valencia region, Int. J. Climatol., 22, 677â€“695, 2002. </reference>
		<reference numeration="59" content_type="text"> Pons, X.: Manual of miramon, Geographic Information System and Remote Sensing Software, Centre de Recerca EcolÃ²gica i Aplicacions Forestals (CREAF): Bellaterra, available at: http://www.creaf.uab.es/miramon, 2006. </reference>
		<reference numeration="60" content_type="text"> Pons, X. and Ninyerola, M.: Mapping a topographic global solar radiation model implemented in a GIS and calibrated with ground data, Int. J. Climatol., 28(13), 1821â€“1834, doi:10.1002/joc.1676, 2008. </reference>
		<reference numeration="61" content_type="text"> Prudhome, C. and Reed, D. W.: Mapping extreme rainfall in a mountainous region using geostatistical techniques: A case study in Scotland, Int. J. Climatol., 19, 1337â€“1356, 1999. </reference>
		<reference numeration="62" content_type="text"> R Development Core Team: $R$: A Language and Environment for Statistical Computing, Vienna (Austria), R Foundation for Statistical Computing, 2008. </reference>
		<reference numeration="63" content_type="text"> Renard, K. G. and Freimund, J. R.: Using monthly precipitation data to estimate the $R$ factor in the revised USLE, J. Hydrol., 157, 287â€“306, 1994. </reference>
		<reference numeration="64" content_type="text"> Renard, K. G., Foster, G. R., Weesies, G. A., McCool, D. K., and Yoder, D. C.: Predicting Soil Erosion by Water: A Guide to Conservation Planning with the Revised Universal Soil Loss Equation (RUSLE), Handbook #703, US Department of Agriculture, Washington, DC, 1997. </reference>
		<reference numeration="65" content_type="text"> Romero, R., Guijarro, J. A., Ramis, C., and Alonso, S.: A 30-year (1964â€“1993) daily rainfall data base for the Spanish Mediterranean regions: first exploratory study, Int. J. Climatol., 18, 541â€“560, 1998. </reference>
		<reference numeration="66" content_type="text"> De Santos Loureiro, N. and De Azevedo Coutinho, M.: A new procedure to estimate the RUSLE EI$_30$~index, based on monthly rainfall data and applied to the Algarve region, Portugal, J. Hydrol., 250, 12â€“18, doi:10.1016/S0022-1694(01)00387-0, 2001. </reference>
		<reference numeration="67" content_type="text"> Shi, Z. H., Cai, C. F., Ding, S. W., Wang, T. W., and Chow, T. L.: Soil conservation planning at the small watershed level using RUSLE with GIS, Catena, 55, 33â€“48, 2004. </reference>
		<reference numeration="68" content_type="text"> Tobler, W. R.: A computer movie simulating urban growth in Detroit region, Econ. Geogr., 46, 234â€“240, 1970. </reference>
		<reference numeration="69" content_type="text"> Verstraeten, G., Poesen, J., DemarÃ©e, G., and Salles, C.: Long-term (105 years) variability in rain erosivity as derived from 10-min rainfall depth data for Ukkel (Brussels, Belgium): implications for assessing soil erosion rates, J. Geophys. Res., 111, D22109, doi:10.1029/2006JD007169, 2006. </reference>
		<reference numeration="70" content_type="text"> Vicente-Serrano, S. M., Saz-SÃ¡nchez, M. A., and Cuadrat, J. S.: Comparative analysis of interpolation methods in the middle Ebro Valley (Spain): application to annual precipitation and temperature, Climate Res., 24, 161â€“180, 2003. </reference>
		<reference numeration="71" content_type="text"> Vicente-Serrano, S. M.: Las sequÃ­as climÃ¡ticas en el valle medio del Ebro: factores atmosfÃ©ricos, evoluciÃ³n temporal y variabilidad espacial, Publicaciones del Consejo de ProtecciÃ³n de la Naturaleza de AragÃ³n, 2005. </reference>
		<reference numeration="72" content_type="text"> Vicente-Serrano, S. M., Lanjeri, S., and LÃ³pez-Moreno, J. I.: Comparison of different procedures to map reference evapotranspiration using geographical information systems and regression-based techniques, Int. J. Climatol., 27, 1103â€“1118, 2007. </reference>
		<reference numeration="73" content_type="text"> Vogt, J. V., Viau, A. A., and Paquet, F.: Mapping regional air temperature fields using satellite derived surface skin temperatures, Int. J. Climatol., 17, 1559â€“1579, 1997. </reference>
		<reference numeration="74" content_type="text"> Wackernagel, H.: Multivariate Geostatistics: an introduction with applications, Springer, Berlin/London, XIV, 1998. </reference>
		<reference numeration="75" content_type="text"> Weisse, A. K. and Bois, P.: A comparison of methods for mapping statistical characteristics of heavy rainfall in the French Alps: The use of daily information, Hydrolog. Sci. J., 47, 739â€“752, 2002. </reference>
		<reference numeration="76" content_type="text"> Weiss, S. M. and Kulikowski, C. A.: Computer Systems That Learn, Morgan Kaufmann, 1991. </reference>
		<reference numeration="77" content_type="text"> Willmott, C. J.: On the validation of models, Phys. Geogr., 2, 184â€“194, 1981. </reference>
		<reference numeration="78" content_type="text"> Willmott, C. J. and Matsuura, K.: Advantages of the mean absolute error (MAE) over the root mean square error (RMSE) in assessing average model performance, Climate Res., 30, 79â€“82, 2005. </reference>
		<reference numeration="79" content_type="text"> Winchell, M. F., Jackson, S. H., Wadley, A. M., and Srinivasan, R.: Extension and validation of a geographic information system-based method for calculating the Revised Universal Soil Loss Equation length-slope factor for erosion risk assessments in large watersheds, J. Soil Water Conserv., 63, 105â€“111, 2008. </reference>
		<reference numeration="80" content_type="text"> Wischmeier, W. H.: A rainfall erosion index for a universal soil-loss equation, Soil Sci. Soc. Am. Pro., 23, 246â€“249, 1959. </reference>
		<reference numeration="81" content_type="text"> Wischmeier, W. H. and Smith, D. D.: Predicting rainfall erosion losses: a guide to conservation planning, USDA Handbook 537, Washington, DC, 1978. </reference>
	</references>
</article>

