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</o:shapelayout></xml><![endif]--></head><body lang=EN-SG link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>I was surprised to find that running on WRF 3.4 the same domain, with the same initial and boundary conditions could get different results. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>I’ve read about the fact that the internal variability of a model can give different results, for the same period of simulation, when the initial conditions change even just for a few days/hours. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>However, running 2 times the same and finding differences till +/- 8m/s in U10 for example is scaring. Anyone can explain me how this is possible?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal align=center style='text-align:center'><span style='mso-fareast-language:EN-SG'><img width=729 height=576 id="Picture_x0020_1" src="cid:image002.jpg@01CDB920.F8DA23B0"></span><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>A Million Thanks in advance!<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Elena<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=360 style='width:270.0pt'><tr><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'>Elena Pison San Pedro<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'>M.Sc. in Atmospheric Sciences</span><span style='font-size:9.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'>Meteorologist/Climate Change Researcher</span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr style='height:15.0pt'><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal style='line-height:15.0pt'><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'> </span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif";mso-fareast-language:EN-SG'><img width=150 height=38 id="Picture_x0020_2" src="cid:image003.gif@01CDB920.F8DA23B0" alt="Description: C:\Users\mmc\AppData\Roaming\Microsoft\Signatures\dhi_logo.gif"></span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr style='height:7.5pt'><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm;height:7.5pt'><p class=MsoNormal style='mso-line-height-alt:7.5pt'><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'> </span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'>DHI-NTU Research Centre and Education Hub,<o:p></o:p></span></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=360 style='width:270.0pt'><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'>DHI Water & Environment (S) Pte Ltd</span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'>1 Clean Tech Loop</span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'>#03-05 CleanTech One</span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'>Singapore 637141</span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr></table></td></tr><tr><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm'><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=360 style='width:270.0pt'><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'></td></tr><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'></td></tr><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'></td></tr><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'></td></tr></table></td></tr><tr><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm'></td></tr><tr><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm'><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=360 style='width:270.0pt'><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'></td></tr><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'></td></tr><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'></td></tr><tr><td valign=top style='padding:0cm 0cm 0cm 0cm'></td></tr></table></td></tr><tr style='height:7.5pt'><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm;height:7.5pt'><p class=MsoNormal style='mso-line-height-alt:7.5pt'><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'> </span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr style='height:6.0pt'><td width=50 valign=top style='width:37.5pt;padding:0cm 0cm 0cm 0cm;height:6.0pt'><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'>Tel: </span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td><td width=5 valign=top style='width:3.75pt;padding:0cm 0cm 0cm 0cm;height:6.0pt'><p class=MsoNormal 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style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><a href="mailto:emp@dhi.com.sg"><span style='color:blue'>emp@dhi.com.sg</span></a></span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr><tr><td colspan=3 valign=top style='padding:0cm 0cm 0cm 0cm'><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><a href="http://www.dhigroup.com/"><span style='color:blue'>www.dhigroup.com</span></a></span><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";mso-fareast-language:EN-SG'><o:p></o:p></span></p></td></tr></table><p class=MsoNormal><span style='mso-fareast-language:EN-SG'><o:p> </o:p></span></p><p 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