Dynamic and Buoyancy Pressure A rising thermal plus… Unix basics

Some Unix basics (basis of Linux and Mac OS X) The command prompt is $ (do not type it) Unix commands presented in Courier font $ ls [lists your “visible” files] $ ls -a [lists all files, including invisible] $ ls -al [lists all files, includes size & other info] $ pwd [print working directory - shows your location]

Some Unix basics (continued) $ mkdir TEST [makes a directory called “TEST”] $ cd TEST [changes directory to “TEST”] $ cd.. [moves UP in directory hierarchy] $ cd TeST [command should FAIL… Unix is usually CASE SENSITIVE – though it isn’t on Mac]

Some Unix basics (continued) $ touch crap.txt [makes an empty file] $ nedit crap.txtOR $ kwrite crap.txt [invoked Notepad-like text editor on Synoptic Lab machines] [add some text, save file and exit] $ ls -al crap.txt [see it’s there] $ cp crap.txt crap.txt.backup [make a copy with cp] $ rm crap.txt [the remove command. Asks for confirmation. Don’t type ‘y’] $ \rm crap.txt [remove without confirmation. Think before hitting ENTER!]

Some Unix basics (continued) $ mkdir BACKUP [makes a new directory] $ cp crap.txt.backup BACKUP/. [type exactly as written - there is NO space before the period] [the period means “keep the same name”] $ ls -al BACKUP/ [see a copy is in the new location] $ mkdir BACKUP/more_backup [a new subdirectory in a directory] $ cd BACKUP/more_backup [move to new subdirectory] $ cd $ pwd [cd by itself always takes you to your home directory]

Some Unix basics (continued) $ cp /home/fovell/part*. [asterisk is wild card character] [copies all files matching text pattern to your directory] $ ls part* [lists files matching pattern] $ cat part1 part2 > both_parts [concatenates files] [greater-than sign is output redirect] $ more both_parts [more lists contents, one screen at a time] [hit space bar for next screenfull, type “q” to quit]

Your Unix PATH $ cp /home/fovell/execute_me. $ execute_me - if you receive execute_me: command not found your PATH needs changing - The PATH is an environment variable that tells Unix where to find stuff, and the order in which to look $./execute_me - this forces Unix to look in the current directory for the program to run

Fortran compiler Try this command $ which ifort If you get this… we definitely need to alter your Unix environment $ ifort: Command not found

Preparation for new users [“old” users may have a.cshrc file instead] $ cd $ mv.tcshrc.tcshrc_old [mv is move command] [.tcshrc or.cshrc is a script file of commands, paths, etc., executed for every new terminal window] $ cat.tcshrc_old /home/fovell/addon.csh >.tcshrc [type exactly as shown] [greater-than sign is output redirect] $ source.tcshrc [changes to script file in present window do not take effect until “sourced”] $ which ifort [now you should see: /opt/intel/Compiler/11.1/046/bin/intel64/ifort ] $ which gradsnc [see /home/fovell/grads-1.9b4/bin/gradsnc ]

DTDM on our Synoptic Lab Linux computers Synoptic Lab computers open during business hours ONLY and printing is difficult $ cp /home/fovell/DTDM_package_linux.tar. [note space and period!] $ tar –xvf DTM_package_linux.tar $ cd DTDM $ make [makes the dtdm executable file]

Using DTDM - 2 $ dtdm < input_thermal.txt [runs model, makes output] [less-than sign provides contents of txt file to the dtdm executable] $ gradsnc -l [starts up GrADS; ga-> is GrADS prompt] ga-> open thermal.anelastic ga-> query file

Using DTDM - 3 File 1 : DTDM demo simulation Descriptor: thermal.anelastic.ctl Binary: thermal.anelastic.dat Type = Gridded Xsize = 99 Ysize = 1 Zsize = 82 Tsize = 11 Number of Variables = 17 u 82 0 horizontal velocity up 82 0 pert horizontal velocity w 82 0 vertical velocity th 82 0 potential temperature thp 82 0 pert potential temperature pi 82 0 ndim pressure pip 82 0 pert ndim pressure ppmb 82 0 pert pressure in millibars pbyc 82 0 buoyancy pressure in millibars pdyn 82 0 dynamic pressure in millibars ptot 82 0 total pressure in millibars dudtd 82 0 U acceleration - dynamic dudtb 82 0 U acceleration - buoyancy dudtt 82 0 U acceleration - total dwdtd 82 0 W acceleration - dynamic dwdtb 82 0 W acceleration - buoyancy dwdtt 82 0 W acceleration - total running dtdm model created two new GrADS files: thermal.anelastic.ctl thermal.anelastic.dat contents of thermal.anelastic.ctl shown at left

ga-> set t 6 ga-> start.gs ga-> d thp

ga-> d ppmb

ga-> c ga-> set ccolor 1 ga-> d pbyc

ga-> c ga-> set ccolor 1 ga-> d pdyn

ga-> c ga-> set ccolor 1 ga-> d w

ga-> c ga-> set gxout shaded ga-> d w ga-> set gxout contour ga-> set ccolor 1 ga-> d dwdtt ga-> scripts/cbarn.gs dwdtt is Lagrangian dw/dt, not Eulerian

ga-> c ga-> set t 9 ga-> set ccolor 1 ga-> set cint 2 ga-> d w

scripts/thermal.gs 'set mproj off' 'set display color white' 'clear' 'set grads off' 'scripts/rgbset.gs' * plot w 'set x 30 70' 'set gxout shaded' 'set clevs ' 'set ccols ' 'd w' 'scripts/cbarn.gs' 'set gxout contour'

ga-> set t 6 ga-> scripts/thermal.gs

Final cautions Make backups This command runs the model $ dtdm < input_thermal.txt This command destroys the input file! $ dtdm > input_thermal.txt

Animations made painless ga-> step.gs thp Plots field thp …with contour interval 1.0 …and steps through times 1 through 11, inclusive …hit return to proceed to the next time

Advice Don’t ask what’s the least you can do for me. Instead, ask what’s the most you can do for yourself.