Comments for Biospherica

Comment on Mapping Biomes by joe

joe — Wed, 28 Dec 2011 13:05:49 +0000

Thanks Paul, I was running R on Windows at the time of this post. On the Mac, quartz() is another alternative.

Comment on Mapping Biomes by Paul dassori

Paul dassori — Sat, 24 Dec 2011 17:06:25 +0000

In Windows, the graphics window is controlled by the windows() command; in unix/linux, the X11 window is controlled by the x11() function. The size of the window is specified in inches as arguments to the function. For example, to get a window 8 inches wide by 6 inches tall

x11(height=6,width=8) or windows(height=6,width=8)

Comment on Mapping Biomes by Paul dassori

Paul dassori — Sat, 24 Dec 2011 16:41:15 +0000

Congratulations, your map is very good.
I need to create a similar map, making his code to activate the “windows ()” the program provides Error: Could not find the “windows”
This library function which belongs?

Thanks for any help-
Greetings from the global south, Valdivia, Chile.

Comment on Ensemble Prediction by Mike

Mike — Wed, 30 Nov 2011 16:23:21 +0000

Thanks. Thats what it looked like to me but as a new user (of R, GRIB2) I wasn’t sure somehow I was modifying the names or doing something wrong. At some point, I guess NECP changed the naming convention of the field to include the ensemble number as part of variable name. Thanks again.

Comment on Ensemble Prediction by joe

joe — Tue, 29 Nov 2011 22:52:41 +0000

The line should be changed to read:

t2m.en[[i]] <- get.var.ncdf(t2m,paste(“TMP__”,i,”_2maboveground”,sep=”"))

I tested the script with that change and it runs correctly.

Comment on Ensemble Prediction by Mike

Mike — Tue, 29 Nov 2011 16:36:23 +0000

Thank you very much for the reply. However, I don’t understand; Are you saying my map is inverted? How do i uninvert it?

Why does the following line from your code return a “variable not found” error?

t2m.en[[i]] <- get.var.ncdf(t2m,"TMP_2maboveground")

When I look at the variable names for the t2m variable (i.e. print(t2m) ) it suggest (I think) that somewhere in the process the variable name has been modified in the follwoing way:

from TMP_2maboveground to TMP__1_2maboveground
from TMP_2maboveground to TMP__2_2maboveground
from TMP_2maboveground to TMP__3_2maboveground
…
from TMP_2maboveground to TMP__20_2maboveground

Will look at the raster doccumetnation but any assistance you could proveivde for this new user would be very much appreciated.

Comment on Ensemble Prediction by joe

joe — Wed, 23 Nov 2011 23:55:27 +0000

Mike,

as a sanity check, try making a map of the ensemble mean. it should be obvious what the problem is e.g. the map is inverted.

by the way, i recommend R’s raster package. it gives a nice concise way of handling weather ensembles.

Comment on Ensemble Prediction by Mike

Mike — Wed, 23 Nov 2011 21:17:30 +0000

This is killing me! Is there any reason why the the TMP_2maboveground variable name would be prefixed by …

TMP__1_2maboveground
TMP__2_2maboveground
TMP__3_2maboveground
…
…
TMP__19_2maboveground

for each of the ensebme runs?

I tested my wgrib2 statement mannually in the command window and it seems to produced the same prefixed variable names listed above which prevent the following line from working:

t2m.en[[i]] <- get.var.ncdf(t2m,"TMP_2maboveground")

I tried adding and modifying the above line to the followig to dynamicaly create the variable name:

nm=paste("TMP__",i,"_2maboveground",sep="");
t2m.en[[i]] <- get.var.ncdf(t2m,nm)

While this does seem to produce the charts the results dont seem reasonable the histograms produce results that show temps in the -30 range (Kelvin?)

I'm so close but cant seem to crack it, and I have become obsessed with figguring this out. Any assistance would be greatly appreciated.

Comment on Ensemble Prediction by Mike

Mike — Tue, 22 Nov 2011 20:50:09 +0000

I am a very new user to R and the weather files so, my appolgies if this is a dumb question. After some work I got wgrib2 and grep installed and workig but run to a error when pulling the 2m temps. It seems that the following line …

t2m.en[[i]] <- get.var.ncdf(t2m,"TMP_2maboveground")

…should be changed to:

t2m.en[[i]] <- get.var.ncdf(t2m,"TMP__1_2maboveground")

Is this correct?

Comment on Large-scale vegetation-rainfall correlations in Africa by Peter Maclean

Peter Maclean — Mon, 24 Oct 2011 23:54:09 +0000

Yes, I will appreciate getting the data.