CAPRI
images/capri_pic_01.jpg images/capri_pic_02.jpg images/capri_pic_03.jpg

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revisionPrevious revision
Next revision
Previous revision
Next revisionBoth sides next revision
capri:concept:spatyields [2011/04/11 09:37] gochtcapri:concept:spatyields [2011/04/11 09:37] – external edit 127.0.0.1
Line 1: Line 1:
 +<HTML>
 +   <div id="content"><!-- Start Inhalt -->
  
 +
 +
 +         <div class=rightwindow>
 +
 +
 +
 +
 +
 +
 +<H2><a class="intext" HREF="/dokuwiki/doku.php?id=capri:concept:spatialdownscaling">Agricultural land use and environmental indicators at 1x1 km grid resolution</A><BR> - Yields and Irrigation share</H2>
 +
 +
 +
 +<hr style="color: 'blue'; height: '2'; text-align: 'left';">
 +
 +Main Contributors: Wolfgang Britz and Gunter Wriedt<BR>
 +
 +GIS processing of MARS yields: Renate Koble and Giulio Marchi
 +
 +<hr style="color: 'blue'; height: '2'; text-align: 'left';">
 +
 +<P>The <B>crop yields</B> are estimated based on estimates of water limited and non-water limited yields, courtesy of the JRC's
 +
 +<a class="intext" HREF="http://www.marsop.info/scripts/mars.exe?page=bg">MARS</a> project, and per grid cell reported as the
 +
 +average of the water limited yield times unity minus the estimated irrigation share for that crop in the pixel cluster plus the non-water
 +
 +limited yields times the estimated irrigation share. A statistical estimator ensures that the average yields as reported in regional agricultural statistics from Eurostat are recovered.</P>
 +
 +
 +
 +
 +
 +<div style="float:right;padding:20px;padding-right:0px">
 +
 +<a href="images\IRR.jpg"><img style="text-decoration: none;border: none;color: white;" src="images\IRR.jpg" width="400px"/></a>
 +
 +</div>
 +
 +
 +
 +<P>The <B>irrigation shares</B> and yields per crop and 1x1 km cell cluster are statistically estimated
 +
 + based on a Highest Posterior Density estimator, which ensures the following conditions:</P>
 +
 +<UL>
 +
 +    <LI><P>The total irrigated area at NUTSIII/NUTSII region reported in the 1999 Farm Structure Survey is recovered</P></LI>
 +
 +    <LI><P>The area weighted average yield per 1x1 km grid cell and crop is identical to the yield found in regional statistics</P></LI>
 +
 +    <LI><P>Average yield per 1x1 km grid cell and crop are a weighted average of the non-irrigated and irrigated potential yields from MARS, multiplied with an identical scaling factor</P></LI>
 +
 +</UL>
 +
 +<P>Given the fact that there are more variables to estimate (irrigation shares per crop and <A HREF="/dokuwiki/doku.php?id=capri:concept:HSMU">HSMU</A>, scaling factors for yields per region), the statistical estimator picks the most probable
 +
 +combination based on minimizing deviations from given information:</P>
 +
 +<UL>
 +
 +   <LI><P>The reported or average irrigation shares at NUTS II level for selected crops. Where no shares had been reported, those had been estimated based on regression models based
 +
 +    the reported average irrigation shares, and using climate data as explanatory variables.</P></LI>
 +
 +   <LI><P>The average irrigation shares per HSMU, defined from the global irrigation map of FAO</P></LI>
 +
 +   <LI><P>A preferred scaling factor of unity for the crop yields</P></LI>
 +
 +</UL>
 +
 +
 +
 +<hr style="color: 'blue'; height: '2'; text-align: 'left';">
 +
 +<H3>More information</H3>
 +
 +<P class="pubparagraph"><span class="pubAuthor">Britz W. and Wriedt G.</span>:<BR>
 +
 +<I><a HREF="..\docs\yields.pdf" class="intext">Pan-European Estimation of crop specific yields and irrigation shares at 1x1 km grid, JRC, 2007 (pdf, foils)</a></I></p>
 +
 +<BR>
 +
 +
 +
 +<font size=1>Last Updated:Tuesday, October 28, 2008
 +
 +</font>
 +
 +         </div><!-- Ende RightWindow -->
 +
 +      </div><!-- Ende content -->
 +</HTML>
   
 
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Share Alike 4.0 International