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Yamamoto, Jorge Kazuo

doi:10.1023/a:1007577916868

Cited by 141 publications

(51 citation statements)

References 7 publications

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“…An absolute value of the uncertainty is given with the standard deviation (Fig. 5, bottom left), calculated according to Yamamoto (2000). It depends on the measured precipitation values.…”

Section: Uncertainty Informationmentioning

confidence: 99%

Global gridded precipitation over land: a description of the new GPCC First Guess Daily product

Schamm

Ziese

Becker

et al. 2014

Earth Syst. Sci. Data

178

109

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Abstract. This paper describes the new First Guess Daily product of the Global Precipitation Climatology Centre (GPCC). The new product gives an estimate of the global daily precipitation gridded at a spatial resolution of 1• latitude by 1 • longitude. It is based on rain gauge data reported in near-real time via the Global Telecommunication System (GTS) and available about three to five days after the end of each observation month. In addition to the gridded daily precipitation totals in mm day −1 , the standard deviation in mm day −1 , the kriging interpolation error in % and the number of measurements per grid cell are also encoded into the monthly netCDF product file and provided for all months since January 2009. Prior to their interpolation, the measured precipitation values undergo a preliminary automatic quality control. For the calculation of the areal mean of the grid, anomalies are interpolated with ordinary block kriging. This approach allows for a near-real-time release. Therefore, the purely GTS-based data processing lacks an intensive quality control as well as a high data density and is denoted as First Guess. The daily data set is referenced under doi:10.5676/DWD_GPCC/FG_D_100. Two further products, the Full Data Daily and a merged satellite-gauge product, are currently under development at Deutscher Wetterdienst (DWD). These additional products will not be available in near-real time, but based on significantly more and strictly quality controlled observations. All GPCC products are provided free of charge via the GPCC webpage: ftp://ftp-anon.dwd.de/pub/data/gpcc/html/download_gate.html.

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“…An absolute value of the uncertainty is given with the standard deviation (Fig. 5, bottom left), calculated according to Yamamoto (2000). It depends on the measured precipitation values.…”

Section: Uncertainty Informationmentioning

confidence: 99%

Global gridded precipitation over land: a description of the new GPCC First Guess Daily product

Schamm

Ziese

Becker

et al. 2014

Earth Syst. Sci. Data

178

109

View full text Add to dashboard Cite

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“…Today, a number of variants of kriging are in general use, and these are simple kriging, ordinary kriging (OK), universal kriging, block kriging, cokriging, and disjunctive kriging. Among the various forms of kriging, OK has been used widely as a reliable estimation method (Yamamoto 2000). Kriging is distinguished from IDW and other interpolation methods by taking into consideration the variance of estimated parameters (Buttner et al 1998).…”

Section: Introductionmentioning

confidence: 99%

“…OK is most commonly adopted for environmental studies (Poon et al 2000;Kravchenko and Bullock 1999;Lin et al 2001;Tranchant and Vincent 2000;Gringarten and Deutsch 2001). A more detailed explanation of the kriging method is given by Stein (1999), Yamamoto (2000), Gringarten and Deutsch (2001), Mcgrath and Zhang (2003), and Cressie (1990). Zimmerman et al (1999) compared the accuracy of OK, Universal Kriging, and IDW methods based on an analysis of synthetic data.…”

Section: Introductionmentioning

confidence: 99%

Groundwater quality mapping in urban groundwater using GIS

Nas

Berktay

2008

Environ Monit Assess

227

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Konya City, located in the central part of Turkey, has grown and urbanized rapidly. A large amount of the water requirement of Konya City is supplied from groundwater. The quality of this groundwater was determined by taking samples from 177 of the wells within the study area. The purposes of this investigation were (1) to provide an overview of present groundwater quality and (2) to determine spatial distribution of groundwater quality parameters such as pH, electrical conductivity, Cl-, SO4(-2), hardness, and NO3- concentrations, and (3) to map groundwater quality in the study area by using GIS and Geostatistics techniques. ArcGIS 9.0 and ArcGIS Geostatistical Analyst were used for generation of various thematic maps and ArcGIS Spatial Analyst to produce the final groundwater quality map. An interpolation technique, ordinary kriging, was used to obtain the spatial distribution of groundwater quality parameters. The final map shows that the southwest of the city has optimum groundwater quality, and, in general, the groundwater quality decreases south to north of the city; 5.03% (21.51 km2) of the total study area is classified to be at the optimum groundwater quality level.

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“…An alternative approach yielding more reliable errors (Yamamoto, 2000) was not implemented due to the enormous increase in computing time. Thus, the determination of accurate uncertainty estimates remains an issue for data sets of high resolution in space and time.…”

Section: Discussionmentioning

confidence: 99%

“…Kriging variance is known to lack precision on a local scale, since local variation of the data is not considered in the estimation of uncertainty. More sophisticated approaches were suggested by Deutsch and Journel (1998) and Yamamoto (2000). However, due to the enormous increase in computing time, as observed in tests using the approach by Yamamoto (2000), we rely on the easily available kriging variance in this work.…”

Section: Uncertainties Of Interpolationmentioning

confidence: 99%

High-resolution daily gridded data sets of air temperature and wind speed for Europe

Brinckmann

Krähenmann

Bissolli

2016

Earth Syst. Sci. Data

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Abstract. New high-resolution data sets for near-surface daily air temperature (minimum, maximum and mean) and daily mean wind speed for Europe (the CORDEX domain) are provided for the period 2001-2010 for the purpose of regional model validation in the framework of DecReg, a sub-project of the German MiKlip project, which aims to develop decadal climate predictions. The main input data sources are SYNOP observations, partly supplemented by station data from the ECA&D data set (http://www.ecad.eu). These data are quality tested to eliminate erroneous data. By spatial interpolation of these station observations, grid data in a resolution of 0.044 • (≈ 5 km) on a rotated grid with virtual North Pole at 39.25 • N, 162 • W are derived. For temperature interpolation a modified version of a regression kriging method developed by Krähenmann et al. (2011) is used. At first, predictor fields of altitude, continentality and zonal mean temperature are used for a regression applied to monthly station data. The residuals of the monthly regression and the deviations of the daily data from the monthly averages are interpolated using simple kriging in a second and third step. For wind speed a new method based on the concept used for temperature was developed, involving predictor fields of exposure, roughness length, coastal distance and ERA-Interim reanalysis wind speed at 850 hPa. Interpolation uncertainty is estimated by means of the kriging variance and regression uncertainties. Furthermore, to assess the quality of the final daily grid data, cross validation is performed. Variance explained by the regression ranges from 70 to 90 % for monthly temperature and from 50 to 60 % for monthly wind speed. The resulting RMSE for the final daily grid data amounts to 1-2 K and 1-1.5 m s −1 (depending on season and parameter) for daily temperature parameters and daily mean wind speed, respectively.

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Untitled

Cited by 141 publications

References 7 publications

Global gridded precipitation over land: a description of the new GPCC First Guess Daily product

Global gridded precipitation over land: a description of the new GPCC First Guess Daily product

Groundwater quality mapping in urban groundwater using GIS

High-resolution daily gridded data sets of air temperature and wind speed for Europe

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