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<h1><b><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New";font-weight:normal'>ALMA</span></font></b><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
font-weight:normal'> MEMO #487 <br>
<br>
Lightning Near Cerro Chascon </span></font></h1>
<h2><b><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New";font-weight:normal'>Seiichi Sakamoto (NAOJ) and Simon
J. E. Radford (NRAO) <br>
<br>
2004-04-23</span></font></b></h2>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>Keywords: site testing, lightning, safety <br>
<br>
We present a preliminary analysis of the spatial and seasonal lightning distribution
near the Cerro</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>Chascon science preserve, probed with a space-borne
imaging sensor and ground-based storm detectors.</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>The lightning flash rate in this area is among the
lowest in the world for comparable latitudes.</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>Thunderstorms only occur around 5 days per year.
Most observed lightning strikes occurred far to the</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>east of Cerro Chascon, in </span></font><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>Bolivia</span></font><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>
and </span></font><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>Argentina</span></font><font size=2
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>.
Lightning was detected primarily during the summer</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>(December-March), particularly in the afternoon and
evening (UT = 16h-1h). Morning (UT = 10h-14h)</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>events were rare. There seem to be two types of
storms - heavy storms from the west, and milder, but</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>more common, storms from the east. No significant
difference was found between the strike rates at </span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span lang=FR
style='font-size:10.0pt;font-family:"Courier New"'>Pampa La Bola and at Llano
de Chajnantor. </span></font></p>
<p class=MsoNormal><font size=3 face=Helvetica><span lang=FR style='font-size:
12.0pt;font-family:Helvetica'> </span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>View a pdf version of ALMA Memo #487. </span></font></p>
<p class=MsoNormal><u><font size=2 color=blue face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:blue'><a
href="http://www.alma.nrao.edu/memos/html-memos/alma487/memo487.pdf">http://www.alma.nrao.edu/memos/html-memos/alma487/memo487.pdf</a></span></font></u></p>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'> </span></font></p>
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