<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Thank you Carlos. Could you check the following statements so that I can confirm that I understand you correctly. <div class="">1) So if giving e_we, e_sn, dx and dy, the dimension of the computation domain can be determined, right? Choosing of dx and dy is up to me without additional constrain?</div><div class="">2) I should only give dx and dy for the first (coarse) domain, and not necessary to give that for other child domains because they can be inferred from parent_grid_ratio.</div><div class=""><br class=""></div><div class="">I have more other questions (sorry -):</div><div class="">1) How could I know what is the input resolution for each domain? More specifically, if I am using gfs data, I knew from the file name that the resolution can be 0.25 degree, 0.5 degree or 1 degree. What should be the corresponding grog_data_res for this case. </div><div class=""><br class=""></div><div class="">2) Is there any criteria to determine parent_time_step_ratio?</div><div class="">3) Is there any constrain on determine e_vert? By constrain, I mean, for example, e_we in namelist.input should be consistent with that in namelist.wps. If not, I can determine e_vert based on desired resolution in vertical direction?</div><div class="">4) How to determine the p_top_requested? </div><div class=""><br class=""></div><div class="">Thank you again.</div><div class=""><br class=""></div><div class="">Zhixuan Cao</div><div class=""><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Sep 6, 2016, at 1:47 PM, Carlos Ross <<a href="mailto:cf.ross@gmail.com" class="">cf.ross@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class="">Hi Zhixuan,<div class="">You're a bit confused.</div><div class=""><br class=""></div><div class="">e_we and e_sn are the domain dimensions. in X and Y.</div><div class=""><span style="font-size:12.8px" class="">geog_data_res is the resolution of the input data.</span><br class=""></div><div class=""><span style="font-size:12.8px" class="">dx and dy are the resolution of the main domain.</span></div><div class=""><span style="font-size:12.8px" class="">parent_grid_ratio is the ratio starting from the main domain.</span><br class=""></div><div class=""><span style="font-size:12.8px" class=""><br class=""></span></div><div class=""><span style="font-size:12.8px" class="">As example:</span></div><div class=""><span style="font-size:12.8px" class=""><br class=""></span></div><div class=""><div class=""><span style="font-size:12.8px" class=""> parent_id = 1,1,2,</span></div><div class=""><span style="font-size:12.8px" class=""> parent_grid_ratio = 1,3,3, (resolution of each domain: 27km, 9km, 3km)</span></div><div class=""><span style="font-size:12.8px" class=""> i_parent_start = 1,20,15,</span></div><div class=""><span style="font-size:12.8px" class=""> j_parent_start = 1,35,15,</span></div><div class=""><span style="font-size:12.8px" class=""> e_we = 100,75,60 (domain dimensions: 100x100, 75x75, 60x60 everyone in grid points)</span></div><div class=""><span style="font-size:12.8px" class=""> e_sn = 100,75,60</span></div><div class=""><span style="font-size:12.8px" class=""> geog_data_res = '10m','5m','2m', (input resolution for each domain)</span></div><div class=""><span style="font-size:12.8px" class=""> dx = 27000, (first domain resolution)</span></div><div class=""><span style="font-size:12.8px" class=""> dy = 27000,</span></div></div><div class=""><span style="font-size:12.8px" class=""><br class=""></span></div></div><div class="gmail_extra"><br class=""><div class="gmail_quote">2016-09-03 17:57 GMT-03:00 Zhixuan Cao <span dir="ltr" class=""><<a href="mailto:hitcaozx@gmail.com" target="_blank" class="">hitcaozx@gmail.com</a>></span>:<br class=""><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi<br class="">
I feel confused on the exact meaning of some parameters in namelist.wps, following user manual can not solve my confusion. Could someone give me some advice on this?<br class="">
<br class="">
Here do these following parameters work together to determine the resolution of grids for nested domain simulation?<br class="">
parent_grid_ratio<br class="">
i_parent_start<br class="">
j_parent_start<br class="">
e_we<br class="">
e_sn<br class="">
geog_data_res<br class="">
<br class="">
1) If geog_data_res gives resolution of grid, then it seems that I do not need e_we and e_sn.<br class="">
2) For nested domain simulation, should geog_data_res be consistent with parent_grid_ratio? For example, if parent_grid_ratio = 1, 3 then geog_data_res has to be something like geog_data_res = 9m, 3m.<br class="">
3) In the tutorial, it says that ( e_we = n* parent_grid_ratio +1) and ( e_sn = n* parent_grid_ratio +1). I guess I can use different n for e_we and e_sn. Am I right? But is there any constrain on n besides that n has to be a positive integer?<br class="">
<br class="">
Thank you very much!<br class="">
<br class="">
Zhixuan Cao<br class="">
<br class="">
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