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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Dear Colleagues: The IGS Troposphere WG Troposphere Comparison website is now open! It allows you to explore what kind of troposphere estimates are available at different locations around the world, and in some cases to compare them. Data types currently included: VLBI, GNSS, radiosondes, and numerical weather models.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Access it here: twg.igs.org/Tropo_Comp_Site/index.php<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Or from the IGS TWG website (twg.igs.org/index.html): click “GOP-IGS Troposphere-Comparison Website” (towards top right of the page, on same line as the giant “Troposphere”).<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Some areas are not yet available, and many need improvement, but we hope you enjoy using the site.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Finally: we thank the many contributors listed below!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Sincerely,<o:p></o:p></p><p class=MsoNormal>Christine Hackman, Jan Dousa and Sharyl Byram<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b><span style='font-size:10.0pt'>Acknowledgements:<o:p></o:p></span></b></p><p class=MsoListParagraphCxSpFirst style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>The International GNSS Service<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>The International VLBI Service<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>The EUREF Permanent GNSS Network<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>The European Centre for Medium-Range Weather Forecasts (ECMWF)<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>Geodetic Observatory Pecny (Czech Republic)<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>The United States Naval Observatory (USA)<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>UNAVCO (USA)<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>Czech Republic Ministry of Education, Youth and Sports Kontakt II Grant LH14089<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>National Oceanic and Atmospheric Administration (USA)<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>Agencia Spaziale Italiana (ASI)<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>The Center for Orbit Determination in Europe (CODE; Switzerland)<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>Military University of Technology (Poland)<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>Federal Office of Topograhy (swisstopo; Switzerland)<o:p></o:p></span></p><p class=MsoListParagraphCxSpMiddle style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>Instituto Geografico Nacional (Spain)<o:p></o:p></span></p><p class=MsoListParagraphCxSpLast style='mso-margin-top-alt:auto;margin-right:45.35pt;mso-margin-bottom-alt:auto;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo2;background:white'><![if !supportLists]><span lang=EN style='font-size:10.0pt;font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN style='font-size:10.0pt'>GeoForschungsZentrum (Germany)<o:p></o:p></span></p><p class=MsoNormal>--------------------------------------------<o:p></o:p></p><p class=MsoNormal>Dr. Christine Hackman, GS-15<o:p></o:p></p><p class=MsoNormal>Head, Earth Orientation Department<o:p></o:p></p><p class=MsoNormal>United States Naval Observatory<o:p></o:p></p><p class=MsoNormal>3450 Massachusetts Ave NW<o:p></o:p></p><p class=MsoNormal>Washington DC 20392 USA<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>tel: (202) 762-1444<o:p></o:p></p><p class=MsoNormal>fax: (202) 762-1563<o:p></o:p></p><p class=MsoNormal>e: christine.hackman@navy.mil <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>