Ground altitude for the same point varies with start date/time
Posted: September 21st, 2017, 9:45 pm
Dear All,
I'm running many backward trajectories starting at the same lat/lon and altitude above ground but separated in steps of 1h, for all hours in a particular month.
The column before last in my output files (endpoint file format) is named TERR_MSL and, as far as I understand, it should be the terrain altitude in meters above sea level, along the trajectory. Therefore, if I look just in the first line of each output file (i.e. time = 0h backwards) this values should always be the same (ground altitude of start position).
In my output files, however, they vary! See:
t140319_0800_backward.dat.T3
8 PRESSURE THETA AIR_TEMP RAINFALL MIXDEPTH RELHUMID TERR_MSL SUN_FLUX
1 1 14 3 19 8 0 2 0.0 -3.213 -60.598 100.0 995.2 297.9 297.5 0.6 41.4 91.7 62.8 0.0
t140319_0900_backward.dat.T3
8 PRESSURE THETA AIR_TEMP RAINFALL MIXDEPTH RELHUMID TERR_MSL SUN_FLUX
1 1 14 3 19 9 0 3 0.0 -3.213 -60.598 100.0 995.7 297.8 297.4 0.7 39.6 92.6 62.7 0.0
t140319_1000_backward.dat.T3
8 PRESSURE THETA AIR_TEMP RAINFALL MIXDEPTH RELHUMID TERR_MSL SUN_FLUX
1 1 14 3 19 10 0 2 0.0 -3.213 -60.598 100.0 995.7 298.2 297.8 0.0 67.5 89.1 51.0 12.8
How can the initial ground altitude be changing?
Is this expected? or is this a bug?
More information:
Running on a SGI cluster, with linux SLES11
Hysplit4 downloaded in July 2015
Input is GDAS 0.5 degrees
TRAJ.CFG======
&SETUP
tratio = 0.75,
delt = 0.0,
mgmin = 10,
khmax = 9999,
kmixd = 0,
kmsl = 0,
kagl = 1,
k10m = 1,
nstr = 0,
mhrs = 9999,
nver = 0,
tout = 60,
tm_pres = 1,
tm_tpot = 1,
tm_tamb = 1,
tm_rain = 1,
tm_mixd = 1,
tm_relh = 1,
tm_sphu = 0,
tm_mixr = 0,
tm_dswf = 1,
tm_terr = 1,
dxf = 1.00,
dyf = 1.00,
dzf = 0.01,
messg = 'MESSAGE',
/
SETUP======
&SETUP
TM_PRES=1,
TM_TPOT=1,
TM_TAMB=1,
TM_RAIN=1,
TM_MIXD=1,
TM_TERR=1,
TM_DSWF=1,
TM_RELH=1,
TOUT=60,
/
ASCDATA.CFG======
-90.0 -180.0 lat/lon of lower left corner
0.5 0.5 lat/lon spacing in degrees
360 720 lat/lon number of data points
2 default land use category
0.2 default roughness length (m)
'../bdyfiles0p5/' directory of files
CONTROL=====
14 01 01 00 30
6
-3.212972 -60.598056 100
-3.139200 -60.131530 100
-3.097220 -59.986700 100
-2.890476 -59.969899 100
-2.594580 -60.209300 100
-2.144111 -58.999861 100
-336
0
10000.0
17
/work/hbarbosa/gdas0p5/
20140102_gdas0p5
/work/hbarbosa/gdas0p5/
20140101_gdas0p5
/work/hbarbosa/gdas0p5/
20131231_gdas0p5
/work/hbarbosa/gdas0p5/
20131230_gdas0p5
/work/hbarbosa/gdas0p5/
20131229_gdas0p5
/work/hbarbosa/gdas0p5/
20131228_gdas0p5
/work/hbarbosa/gdas0p5/
20131227_gdas0p5
/work/hbarbosa/gdas0p5/
20131226_gdas0p5
/work/hbarbosa/gdas0p5/
20131225_gdas0p5
/work/hbarbosa/gdas0p5/
20131224_gdas0p5
/work/hbarbosa/gdas0p5/
20131223_gdas0p5
/work/hbarbosa/gdas0p5/
20131222_gdas0p5
/work/hbarbosa/gdas0p5/
20131221_gdas0p5
/work/hbarbosa/gdas0p5/
20131220_gdas0p5
/work/hbarbosa/gdas0p5/
20131219_gdas0p5
/work/hbarbosa/gdas0p5/
20131218_gdas0p5
/work/hbarbosa/gdas0p5/
20131217_gdas0p5
/home/hbarbosa/hysplit/goam0p5/backward/
t140101_0030_backward.dat
I'm running many backward trajectories starting at the same lat/lon and altitude above ground but separated in steps of 1h, for all hours in a particular month.
The column before last in my output files (endpoint file format) is named TERR_MSL and, as far as I understand, it should be the terrain altitude in meters above sea level, along the trajectory. Therefore, if I look just in the first line of each output file (i.e. time = 0h backwards) this values should always be the same (ground altitude of start position).
In my output files, however, they vary! See:
t140319_0800_backward.dat.T3
8 PRESSURE THETA AIR_TEMP RAINFALL MIXDEPTH RELHUMID TERR_MSL SUN_FLUX
1 1 14 3 19 8 0 2 0.0 -3.213 -60.598 100.0 995.2 297.9 297.5 0.6 41.4 91.7 62.8 0.0
t140319_0900_backward.dat.T3
8 PRESSURE THETA AIR_TEMP RAINFALL MIXDEPTH RELHUMID TERR_MSL SUN_FLUX
1 1 14 3 19 9 0 3 0.0 -3.213 -60.598 100.0 995.7 297.8 297.4 0.7 39.6 92.6 62.7 0.0
t140319_1000_backward.dat.T3
8 PRESSURE THETA AIR_TEMP RAINFALL MIXDEPTH RELHUMID TERR_MSL SUN_FLUX
1 1 14 3 19 10 0 2 0.0 -3.213 -60.598 100.0 995.7 298.2 297.8 0.0 67.5 89.1 51.0 12.8
How can the initial ground altitude be changing?
Is this expected? or is this a bug?
More information:
Running on a SGI cluster, with linux SLES11
Hysplit4 downloaded in July 2015
Input is GDAS 0.5 degrees
TRAJ.CFG======
&SETUP
tratio = 0.75,
delt = 0.0,
mgmin = 10,
khmax = 9999,
kmixd = 0,
kmsl = 0,
kagl = 1,
k10m = 1,
nstr = 0,
mhrs = 9999,
nver = 0,
tout = 60,
tm_pres = 1,
tm_tpot = 1,
tm_tamb = 1,
tm_rain = 1,
tm_mixd = 1,
tm_relh = 1,
tm_sphu = 0,
tm_mixr = 0,
tm_dswf = 1,
tm_terr = 1,
dxf = 1.00,
dyf = 1.00,
dzf = 0.01,
messg = 'MESSAGE',
/
SETUP======
&SETUP
TM_PRES=1,
TM_TPOT=1,
TM_TAMB=1,
TM_RAIN=1,
TM_MIXD=1,
TM_TERR=1,
TM_DSWF=1,
TM_RELH=1,
TOUT=60,
/
ASCDATA.CFG======
-90.0 -180.0 lat/lon of lower left corner
0.5 0.5 lat/lon spacing in degrees
360 720 lat/lon number of data points
2 default land use category
0.2 default roughness length (m)
'../bdyfiles0p5/' directory of files
CONTROL=====
14 01 01 00 30
6
-3.212972 -60.598056 100
-3.139200 -60.131530 100
-3.097220 -59.986700 100
-2.890476 -59.969899 100
-2.594580 -60.209300 100
-2.144111 -58.999861 100
-336
0
10000.0
17
/work/hbarbosa/gdas0p5/
20140102_gdas0p5
/work/hbarbosa/gdas0p5/
20140101_gdas0p5
/work/hbarbosa/gdas0p5/
20131231_gdas0p5
/work/hbarbosa/gdas0p5/
20131230_gdas0p5
/work/hbarbosa/gdas0p5/
20131229_gdas0p5
/work/hbarbosa/gdas0p5/
20131228_gdas0p5
/work/hbarbosa/gdas0p5/
20131227_gdas0p5
/work/hbarbosa/gdas0p5/
20131226_gdas0p5
/work/hbarbosa/gdas0p5/
20131225_gdas0p5
/work/hbarbosa/gdas0p5/
20131224_gdas0p5
/work/hbarbosa/gdas0p5/
20131223_gdas0p5
/work/hbarbosa/gdas0p5/
20131222_gdas0p5
/work/hbarbosa/gdas0p5/
20131221_gdas0p5
/work/hbarbosa/gdas0p5/
20131220_gdas0p5
/work/hbarbosa/gdas0p5/
20131219_gdas0p5
/work/hbarbosa/gdas0p5/
20131218_gdas0p5
/work/hbarbosa/gdas0p5/
20131217_gdas0p5
/home/hbarbosa/hysplit/goam0p5/backward/
t140101_0030_backward.dat