<p><span lang="EN-US">Hi everyone</span><br></p>
<p style="text-indent:21.0pt;mso-char-indent-count:2.0"><span lang="EN-US">I am trying to run a regional model in Ross sea with the <a name="OLE_LINK1" target="_blank">curvilinear grid</a>. But I encounter a problem, that is, the
AngleCS and AngleSN generated by the model will have an abrupt change at the
north (last column)/east (last row) boundaries. In other words, the value of
AngleCS and AngleSN should be as close to the adjacent column/row as the other
columns/rows at the last columns/rows. But the AngleCS mostly going to be 1/0,
AngleSN close to 0/1. </span></p>
<p style="text-indent:21.0pt;mso-char-indent-count:2.0"><span lang="EN-US">We conduct a few tests to figure out what happened, and read some code then we
found some results. If the latitude of the region we selected were
symmetric, the AngleCS and AngleSN file would be fine everywhere (e.g., the Pan¨CAntarctica
region with latitude and longitude shown in Figure 1 and Figure 2). But If the domain
only contains one half of the Antarctica (e.g., the half longitude from 0E to
180E), we find that only the northern boundary (last column) has the sharp
changes in the AngleCS/SN and the eastern boundary (last row) changes smoothly
as expected. </span></p>
<p style="text-indent:21.0pt;mso-char-indent-count:2.0"><span lang="EN-US">At the current stage, I think I may try to use the following two
methods to avoid the sharp changes of the angle value at the northern and
eastern boundaries as follows:</span></p>
<p style="text-indent:21.0pt;mso-char-indent-count:2.0"><span lang="EN-US">1) I can use the AngleCS and
AngleSN data of the penultimate row and the penultimate column at the northern
or eastern boundaries; </span></p>
<p style="text-indent:21.0pt;mso-char-indent-count:2.0"><span lang="EN-US">2) I can create a larger domain and take out the AngleCS and AngleCS
data in my smaller domain where I am interested.</span></p>
<p style="text-indent:21.0pt;mso-char-indent-count:2.0"><span lang="EN-US">However, I still want to know what causes this problem, and whether
the two methods mentioned above are correct, since I have to apply these angle
file to my prescribed open boundary conditions. I am really appreciated to any
help and suggestions.</span></p>
<p><span lang="EN-US"> <img src="cid:446a33ca$1$16dfb833228$Coremail$liangjun.yan$hhu.edu.cn"><img style="color: rgb(0, 0, 0); font-family: "ËÎÌå",arial,Verdana,sans-serif; font-size: 14px; font-style: normal; font-variant: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: left; text-decoration: none; text-indent: 0px; text-transform: none; -webkit-text-stroke-width: 0px; white-space: normal; word-spacing: 0px;" src="cid:186e35dd$2$16dfb833228$Coremail$liangjun.yan$hhu.edu.cn"><img src="cid:6b924cb2$3$16dfb833228$Coremail$liangjun.yan$hhu.edu.cn"><img src="cid:51e9714a$4$16dfb833228$Coremail$liangjun.yan$hhu.edu.cn"></span></p>
<p><span lang="EN-US">Best regards,</span><span lang="EN-US"> </span></p>
<p><span lang="EN-US">Liangjun Yan</span><span lang="EN-US"><br></span></p>
<p><span lang="EN-US"><i>Master student, Physical Oceanography</i></span><span lang="EN-US"><i><br></i></span></p>
<p><u><span lang="EN-US"><font size="2"><a href="mailto:Liangjun.yan@hhu.edu.cn" target="_blank">Liangjun.yan@hhu.edu.cn</a></font></span></u><u><span lang="EN-US"><br></span></u></p>
<p><span lang="EN-US"><i><font size="2">NO.1, Xikang Road, Nanjing, 210098£¬China</font></i></span></p>
<p><span lang="EN-US"><i><font size="2">Hohai Universuty</font></i></span></p>