<a href="https://en.wikipedia.org/wiki/2003_European_heat_wave" class="extiw" title="en:2003 European heat wave">2003 heat wave</a> temperature variations relative to July 2001 temperatures in Europe.
<p>"Compared to July 2001, temperatures in July 2003 were sizzling. This image shows the differences in day time land surface temperatures collected in the two years by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite." (quoted from <a rel="nofollow" class="external autonumber" href="http://earthobservatory.nasa.gov/IOTD/view.php?id=3714">[1]</a>)
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"TERRA MODIS derived land surface temperature data. The difference in land surface temperature is calculated by subtracting the average of all cloud free data during 2000, 2001, 2002 and 2004 from the ones in measured in 2003, covering the date range of July 20 - August 20." (quoted from <a rel="nofollow" class="external autonumber" href="http://www.iac.ethz.ch/staff/fischer/2003.html">[2]</a>)
"Image courtesy Reto Stockli and Robert Simmon, based upon data provided by the MODIS Land Science Team." <a rel="nofollow" class="external autonumber" href="http://earthobservatory.nasa.gov/IOTD/view.php?id=3714">[3]</a>
<a rel="nofollow" class="external free" href="http://earthobservatory.nasa.gov/IOTD/view.php?id=3714">http://earthobservatory.nasa.gov/IOTD/view.php?id=3714</a> (<a rel="nofollow" class="external text" href="http://eoimages.gsfc.nasa.gov/images/imagerecords/3000/3714/modis_lst_europe_2001-2003_lrg.jpg">image</a>)