<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px"><div>Hi all, </div><div> </div><div>I am attempting to build an array of GFS model data, but I am running into some trouble when it comes to defining my Cartesian nodes in the ModelGrib function. </div><div> </div><div>I'll walk you through my code before that point... I pull the current day 0z GFS_hd run and then specify a given lat lon area along with certain variables to reduce the size of the data that I am reading in. From there, I run the DODSGrab function to pull in 36 hours worth of forecast data (gfs_hd) which works fine. </div><div> </div><div>From there, my troubles begin with the ModelGrid function. I believe I have all the arguments correct other than Cartesian.nodes, but I am skeptical on the resolution... not completely sure if I did that correctly. When it
comes to the Cartesian.nodes function, I'm not exactly sure what to put in the argument. I understand that it has to be a list with an x and y element, but I can't find any literature on the gfs_hd grid in kilometers. Any thoughts on how to move forward here?</div><div> </div><div>Thank you. </div><div> </div><div> </div><div>Code is listed below. I am running on a windows 7 machine so pulling Grib data is not an option for me, unfortunately. </div><div> </div><div>#############################################3</div><div> <br> library("rNOMADS")<br> library("RCurl")<br> <br> GFS.list <- GetDODSDates(abbrev="gfs_hd", archive=F, request.sleep=1) #returns list of available dates with GFS data in a numerical list<br> <br> <br> current.GFS.url <- tail(GFS.list$url, 1)<br> GFS.model.runs <- GetDODSModelRuns(current.GFS.url)<br> <br> GFS.0z <-
(head(GFS.model.runs$model.run,1))<br> <br> #run when needed <br> #GFS.info.variables <- GetDODSModelRunInfo(current.GFS.url, GFS.0z)<br> <br> lon <- c(480, 620) # USA Longitude<br> lat <- c(240, 280) # USA Latitude<br> <br>variables <- c("tmax2m","tmin2m", "weasdsfc", "ugrdmwl", "vgrdmwl")<br> <br>GFS.Model.Data <- DODSGrab(current.GFS.url, GFS.0z, variables, time = c(0,36), lon, lat)</div><div style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 12px; font-style: normal; background-color: transparent;"> </div><div>GFS.modelgrid <- ModelGrid(model.data = GFS.Model.Data, grid.type = "cartesian", resolution = c(-140,40),levels = c("surface","2_m_above_ground"), variables, model.domain = NULL, cartesian.nodes =
(list(x=0.5,y=0.5)))</div><div> </div><div>########################################################################</div><div> </div><div>Adam </div></div></body></html>