OASIS98: Logbook Entries

OASIS98: Site NCAR Messages, 28 Entries..

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Entry Date Title Site Author #Graphics
157 Fri 24-Jul-1998Change 1m. Wind SensorNCARKathy Jirak
152 Wed 22-Jul-1998SOIL GRAVMOIST BLKDENS VWF and CsNCARTony Delany
144 Tue 21-Jul-1998Cleaned radiometer domesNCARTony Delany
121 Wed 15-Jul-1998BOUYANCY DETERMINED BULK DENSITIESNCARTony Delany
117 Tue 14-Jul-1998Soil core, pit and clod samples takenNCARTony Delany
116 Tue 14-Jul-1998atm.9m remounted NCARSteve Oncley
114 Mon 13-Jul-1998second K-probe back at 1mNCARSteve Oncley
113 Mon 13-Jul-1998THR 1.5 HC11 swappedNCARSteve Oncley
111 Sun 12-Jul-1998Soil core and trench samples TrimeNCARTony Delany
109 Sun 12-Jul-1998trh at 1.5m restartedNCARSteve Oncley
106 Fri 10-Jul-1998Moist layer in soilNCARTony Delany
104 Thu 09-Jul-19989m ATI taken downNCARSteve Oncley
103 Thu 09-Jul-1998pressure temperature compensationNCARSteve Oncley
100 Wed 08-Jul-1998Soil parameters & storage termNCARTony Delany
99 Wed 08-Jul-1998Soil cores taken/Trime measurementNCARTony Delany
98 Wed 08-Jul-1998lots of rain last nightNCARSteve Semmer
97 Tue 07-Jul-1998Re-planted Gsoil and Tsoil NCAR1NCARTony Delany
96 Tue 07-Jul-1998flipped 6.5m prop vaneNCARSteve Semmer
95 Tue 07-Jul-1998wet towel on sonicNCARSteve Oncley
94 Tue 07-Jul-1998fine adjustments to RHsNCARSteve Oncley
93 Tue 07-Jul-1998photos takenNCARSteve Oncley
92 Tue 07-Jul-1998Cleaned NCAR krypton hygrometersNCARTom Horst
91 Tue 07-Jul-1998Bulk Density of soilNCARTony Delany
90 Tue 07-Jul-1998flipped vane on 2mNCARSteve Oncley
87 Sun 05-Jul-1998Soil samples taken/Trime measurement madeNCARTony Delany
85 Sat 04-Jul-1998Night-time response of Eppley short wave radiometersNCARTony Delany
84 Sat 04-Jul-1998Replacement of 6.5m TRHNCARTony Delany
52 Mon 29-Jun-1998Adjusted level of NCAR RnetNCARTom Horst


157: PROPS, Site NCAR, Fri 24-Jul-1998 12:30:48 CDT, Change 1m. Wind Sensor
Swapped out 1m. wind sensor. 12:30p.m. Old serial number 001, new serial number 002. No more spares. Wobbles in the wind. Looks like bent shaft as well as burnt bearings.

Entered 305 as prop pitch as that is what was in old sensor. We are now using same prop in new sensor.


152: SOIL_SENSORS, Site NCAR, Wed 22-Jul-1998 16:56:22 CDT, SOIL GRAVMOIST BLKDENS VWF and Cs
This logbook entry uses the data from LOGBOOK # 40.
Using the following parameters:
Cm = 1.9 MJ.m-3.degreeK-1
Co = 2.5
Cw = 4.2
vmf = 0.65
vof = 0.01
vwf = blkdens(or BD) * gwf(or gravmoist or gravimetric water fraction or GF)
Cs  =   Cm * vnf       +   Co * vof     + Cw  * blkdens * gwf
    =    1.22          +    0.03        + 4.2 * blkdens * gwf
    =               1.25                + 4.2 * blkdens * gwf

Corer (SS)
date/time (CT)	depth	wet	dry1	dry2	dry3	GF     BD
6/26 11:30      4 cm    118.1   112.3   112.1   111.7  .06    1.22
6/26 11:45	6 cm	191.4	182.2	181.2	180.7  .06    1.33


Corer separated samples (TD)
Date / Time  Depth       Fresh  Dry   Diff  Grav fract  blkdens   vwf  Cs
5 Jul 09:30  0-6cm        25.6  24.6   1.0  0.041 
                          20.7  19.9   0.8  0.042 0.040
                          24.3  23.4   0.9  0.038

Waxed clod (TD)
Date/ Time   Depth  Vol  Fresh  Dry   Diff  Grav fract  blkdens   vwf    Cs
5 Jul 10:00  0-3     39    ~    59.2    ~     ~          1.50
             3-6cm   86    ~   120.3    ~     ~          1.40
 
Corer total (TD)
Date/ Time   Depth  Vol  Fresh  Dry    Diff  Grav fract  blkdens  vwf    Cs
7 Jul 10:00  0-6cm  137   173.9 168.7   5.2   0.031       1.23

Corer separated (TD)
Date/ Time   Depth  Vol  Fresh  Dry    Diff  Grav fract  blkdens  vwf    Cs
8 Jul 09:30  0-3cm  ~     83.3  69.1   14.2   0.205           ~
             3-6cm  ~     88.6  80.5    8.1   0.101           ~

Soil pit (TD)
Date/ Time   Depth  Vol  Fresh  Dry   Diff  Grav fract   blkdens  vwf    Cs
12 Jul 0930  0-6cm    ~   19.3  18.4   0.9   0.049
                          21.2  20.2   1.0   0.050 0.049    ~
                          22.0  21.0   1.0   0.048

Corer total (TD)
Date/ Time   Depth  Vol  Fresh  Dry   Diff  Grav fract   blkdens  vwf   Cs
12 Jul 0930  0-6cm  137  184.0  173.3 10.7   0.062        1.26

Soil pit (TD)
Date/ Time   Depth  Vol  Fresh  Dry   Diff  Grav fract   blkdens  vwf   Cs
14 Jul 0930  0-6cm    ~    20.6 19.9   0.7   0.035
                           27.4 26.5   0.9   0.034 0.035
                           32.5 31.4   1.1   0.035

Corer total (TD)
Date/ Time   Depth  Vol  Fresh  Dry   Diff  Grav fract   blkdens  vwf   Cs
14 Jul 0900  0-6cm  137   183.0 175.8  7.2   0.041

Soil clod (TD)
Date/ Time   Depth  Vol   Fresh  Dry   Diff  Grav fract  blkdens  vwf   Cs
14 Jul 0900  0-6cm  89.6  134.0  129.2  4.8  0.037         1.44
             0-6cm  80.2  118.8  114.2  4.6  0.040 0.036   1.42
             0-6cm  57.1   83.6   81.0  2.6  0.032         1.42

Soil pit (TD)
Date/ Time   Depth  Vol   Fresh   Dry   Diff Grav fract  blkdens  vwf   Cs
18 Jul 0930  0-6cm   ~     26.4   23.4  1.0  0.043
                           25.7   24.7  1.0  0.041 0.041
                           26.2   25.2  1.0  0.040

Corer total (TD)
Date/ Time   Depth  Vol   Fresh   Dry   Diff Grav fract  blkdens  vwf   Cs
18 Jul 0930  0-6cm  137   174.6   168.3  6.3 0.037       1.23

Soil clod
Date/ Time   Depth  Vol   Fresh   Dry   Diff Grav fract  blkdens  vwf   Cs
18 Jul 0930  0-6cm  153.4 222.6   214.1  8.5  0.040      1.40
                    93.2  137.3   131.7  5.6  0.043      1.41            
                  


Date/ Time   Depth  Vol   Fresh  Dry    Diff Grav fract  blkdens  vwf   Cs



144: RADIATION, Site NCAR, Tue 21-Jul-1998 09:40:47 CDT, Cleaned radiometer domes
At 09:00 I cleaned the domes of the four component array
and the Q7.
I also checked the level of the leveling platform (Swartzenager).
It was level, N-S, E-W, to ~ 0.2 degrees.
121: SOIL_SENSORS, Site NCAR, Wed 15-Jul-1998 09:46:48 CDT, BOUYANCY DETERMINED BULK DENSITIES
A bouyancy method was devized to determine the bulk density of the soil.
The soil at OASIS is compact and lends itself to the clod method of bulk
density determination. A chunk of the uppermost ~10cm of soil is brought
into the trailer and, using a plasterers trowel and a small saw, is shaped
into regular rectangular prisms, 6 cm deep and ~ 4 cm on a side.

The prisms are weighed fresh, baked for two days and then weighed dry. 
Melted parawax is dribbled all over the dried clod using a heat gun so
the clod is impregnated with wax and made water proof without altering 
its form or volume. 
Conventionally the volume of the clod is then determined by displacement 
of the water level in a graduated container.

A second method of determining volume involves weighing the waxed clod
in air and then suspended in water. Fortunately the soil balance has
a suspension hook which enable this to be done.

Apparent wt of waxed clod suspd in water = wt of waxed clod - bouyancy

Bouyancy of waxed clod = Volume of waxed clod * density of water
  
      M.wx.sus        =   M.wx   - V.wx * 1
      V.wx            =   M.wx   - M.wx.sus

Bulk density of dry clod  =  Mass of dry clod / Volume of dry clod
      blkdens             =  M.dry            /   V.dry
        
Volume of dry clod   =  Volume of waxed clod
        V.dry        =        V.wx            
                     =  M.wx - M.wx.sus

        blkden       =  M.dry / M.wx - M.wx.sus 
             

Example: The clod made from the sample collected 5 Jul, weighed dry 7 Jul and
had bouyancy determined 15 Jul

   Top 6cm clod dry weight              , M.dry       = 120.3g
   Top 6cm clod waxed weight            , M.wx        = 136.4g
   Top 6cm clod waxed, suspended weight , M.wx.sus    =  50.4g
        
   blkdens = M.dry / ( M.wx  - M.wx.sus )
           = 120.3 / ( 136.4 - 50.4 )
           = 120.3 /  86.0
           = 1.40 g . cm-3

Date     Depth   Fresh   Dry     Waxed   Immersed    Volume    Bulk density
 5 Jul   0-6cm           120.3   136.4     50.4       86.0       1.40
         0-3cm            59.2    64.1     25.1       39.0       1.52

Date     Depth   Fresh   Dry     Waxed   Immersed    Volume    Bulk density
14 Jul   0-6cm   134.0   129.2   139.1     49.5       89.6       1.44
         0-6cm   118.8   114.2   121.8     41.6       80.2       1.42
         0-6cm    83.6    81.0    87.7     30.6       57.1       1.42


Date     Depth   Fresh   Dry     Waxed   Immersed    Volume    Bulk density



117: SOIL_SENSORS, Site NCAR, Tue 14-Jul-1998 10:24:09 CDT, Soil core, pit and clod samples taken
At 09:00 CDT soil samples were taken from the area north of the rad stand.

A soil core was made and the top 0-6cm taken for a single sample.

A soil pit was dug ~12cm deep. A ~ 500g sample of the top 0-6cm portion
of the dressed edge was taken. Three soil moisture aliquots were made.

Two 12 cm deep chunks of the surface soil were extracted. On the bench three
rectangular prism clods were sawed from the chunk for soil moisture and
bulk density determination.

see #40


116: SONICS, Site NCAR, Tue 14-Jul-1998 09:11:46 CDT, atm.9m remounted
We've RTV'd the ati K-probe back together.  I also did a laboratory (trailer)
zero calibration on all 3 paths.  It found biases of about 1 cm/s and path-
lengths of about 14.6 cm for all paths.  

The boom is drooping a bit, just due to the weight.  I've done as much as
I can with the yoke - there is a bit of play in the square part of the yoke.
We could try shimming.  For the moment, I've just left the droop in, assuming
that it can be removed later by tilt.sonic.

We still need to shoot the new boom angle.  I wouldn't expect it to have
changed much.

114: SONICS, Site NCAR, Mon 13-Jul-1998 15:49:15 CDT, second K-probe back at 1m
We installed the replacement U2 transducer in the ati K-probe and have
had it running at 1m on the UW tower for about an hour.  We'll continue
to run it for a while to decide if it is working well enough to mount at 9m.

When we do, we will have to:
1. zero it
2. feed a bit more cable up the tower
3. shoot the boom angle.

113: HYGRO, Site NCAR, Mon 13-Jul-1998 12:05:46 CDT, THR 1.5 HC11 swapped
The T/RH at 1.5m was dead again this morning, having died at ~06:05 UTC.

I decided to swap the HC11 boards with the spare we have.  Of course,
it also was necessary to swap the coefficients.  Before the swap, I saved 
the coefficients as:
$ASTER/projects/OASIS98/doc/trh1.doc & trh3.doc.

Then, I reprogramed TRH003 with the coefficients from TRH001 (using COFL).
NOTE: I DID NOT CHANGE THE SERIAL NUMBERS, SO THE SERIAL NUMBERS ARE OF
THE HC11 AND NOT THE SENSOR.

I loaded sensor #1's coefficients into CPU #3
I pulled the old sensor with CPU #1 from the tower.
I swapped brains in the trailer.
I reinstalled the sensor with CPU #3.
I loaded sensor #3's coefficients back into CPU #1 (the spare), just to be
safe.

Thus, CPU #3 should be debugged in the lab, if possible.

111: SOIL_SENSORS, Site NCAR, Sun 12-Jul-1998 10:06:16 CDT, Soil core and trench samples Trime
At 09:00 both a soil core sample and a soil trench sample were taken
in the area north  of the roped-off radiometer stand.
Soil core, 0-6cm, fresh wt = 184.0g
Soil trench, 0-6cm, fresh wts  CI  = 19.3g    CII = 21.2g   CIII = 22.0g

At 10:00 the Trime probes were inserted  Readings:
    Moisture  Vol%   6.7%   6.8%   6.9% 
    TDR level        56.0   56.0   56.0
Left probes in the ground to see if the readings will change with time,

At 10:35 
    Moisture Vol%    7.2%   7.1%   7.1%
    TDR level        54      55    55

At 11:00
    Moisture Vol%    7.1%   7.1%   7.1%
    TDR level        54.0   55     55

The difference between the fist set of readings and all subsequent readings
may also have been due to the heating of the Trime electronics, as the sun
caused the box to heat considerably.
109: HYGRO, Site NCAR, Sun 12-Jul-1998 09:12:14 CDT, trh at 1.5m restarted
The TRH at 1.5m died at 07:54 GMT last night.  We have no idea why.

rserial didn't respond to wake it up; however the fan was running when 
we went out to check on it (therefore it had power).
Cycling power brought it back to life.

(What good is COP if it allows this to happen?)

106: SOIL_SENSORS, Site NCAR, Fri 10-Jul-1998 10:21:38 CDT, Moist layer in soil
The major thunderstorm at 03:30 dumped heavy rain, leaving puddles on the dirt
road to the site. For the next three days test pits were dug at ~ 09:30
 8 July:    top 2.5cm of soil noticeably dark, below still dry.
 9 July:    top 3.5cm of soil dark
10 July:    soil apparently uniform to inspection

Gravimetric soil moisture meaurements were made on 7 July, prior to the rain,
and on 8 July, after the rain measurements were made of 0-3cm and 3-6cm.

see #40 

104: SONICS, Site NCAR, Thu 09-Jul-1998 12:05:16 CDT, 9m ATI taken down
To allow us to check why the 9m ATI is spiking on U, I've climbed the tower
and taken the sonic head down.  (The Krypton is still mounted to the boom
at 9m).  Note that I had to disconnect the yoke in order to give the cables
enough play to allow me to pull the head out of the boom, so TILT CORRECTIONS
WILL NEED TO BREAK THE FIT AT THIS TIME.

The head is now reconnected and running on channel 201, but is physically
at 1m on the UW test tower (which has no other sonic running on it yet).
Already the U channel appears to be spiking, so this is a good test 
configuration.

We're going to lunch now.  Assuming that it is still bad after lunch, I'll
try looking at the signals on the scope.

----------------------------------
5:30 PM
It appears that the u signal is weak, I think going from u2 -> u1 (the
4th of 6 transmissions).  I'm going to try to get another transducer sent
here as a replacement.  Note that this sonic has been off and on all
day as I fiddled with it - all at 1m on the UW tower.  I've taken it off
completely for the night, since it is not weather tight.  I'll put it 
back up to 9m tomorrow.

103: BAROMETER, Site NCAR, Thu 09-Jul-1998 10:46:42 CDT, pressure temperature compensation
I've been playing with the temperature error in our pressure data.  I get
a reasonable fit with:

pNCAR = pOU - 0.2 (T1.5-27)

The fit has somewhat less scatter if I include a 10-20 min delay between 
the pressures and temperature.

100: SOIL_SENSORS, Site NCAR, Wed 08-Jul-1998 16:03:46 CDT, Soil parameters & storage term
See ASTER/delany/soilparameters.ps for table of soil parameters for previous 
deployments.

Deployment        mindens    vmf     vof    blkdens          Cs
----------------------------------------------------------------------------
                  g cm-3     ~        ~    g.cm-3    MJ.m-3. degreeK-1
------------------------------------------------------------------------------
SJVAQS                                              1.04 + 0.03 + 6.12*gravmoist 

STORMFEST92 est    2.65      0.55    0.01   1.45   1.05 + 0.03 + 6.09*gravmoist

STORMFEST92 meas   2.17      0.47    0.01   1.38   0.89 + 0.03 + 5.80*gravmoist

FOOTPRINT92        2.22      0.65    0.01   1.43   1.24 + 0.03 + 6.01*gravmoist

CACHE94

FLATLAND96

CASES98

OASIS98 est        2.5       0.64    0.01   1.60    1.22 + 0.03 + 6.7*gravmoist     

blkdens     =  dry soil mass / dry soil volume                 g.cm-3
gravmoist   =  (wet soil mass - dry soil mass)/ dry soil mass  g.g-1
vmf         =  blkdens / mindens                               g.cm-3. g-1.cm3
vwf         =  gravmoist x blkdens                             g.cm-3. g-1.cm3
Cm          = 0.46 cal.cm-3.degreeK-1  =                1.9    MJ.m-3.degreeK-1
Co          = 0.60 cal.cm-3.degreeK-1  =                2.5    MJ.m-3.degreeK-1
Cw          = 1.00 cal.cm-3.degreeK-1  =                4.2    MJ.m-3.degreeK-1

An approximate calculation of the soil volumetric heat capacity using previous 
data

Cs =   Cm x vmf  +   Co x vof  +   Cw x vwf                   MJ.m-3.degreeK-1
   = (1.9 x vmf) + (2.5 x vof) + (4.2 x blkdens x gravmoist)  MJ.m-3.degreeK-1
   = (1.9 x 0.64)+ (2.5 x 0.01)+ (4.2 x 1.6 x gravmoist)      MJ.m-3.degreeK-1
   = (1.9 x 0.64)+ (2.5 x 0.01)+ (6.7 x 0.1)                  MJ.m-3.degreeK-1
   =      1.22    +     0.03    +     0.67                    MJ.m-3.degreeK-1
   =                    1.92                                  MJ.m-3.degreek-1

Crude calculation of the magnitude of the storage term, S

Typical heating/cooling is 15 degree in 12 hr (= 50000s)
If a simple linear heating and cooling at the surface occured, then: 
  
Ht 1m2 to 5cm by 1degreeK in  1s for Cs=1.9 MJ.m-3.degreeK-1
   0.05m3,       1degreeK,    1s,       1.9 MJ m-3.degreeK-1;  0.095 MJ.s.m-2
                                                             95000    J.s.m-2
                          
Ht 1m2 to 5cm by 1  degreeK.in 1000s ....................... ;  95    J.s.m-2

Ht 1m2 to 5cm by 1  degreeK in 50 x 1000s .................   ;  1.9    J.s.m-2

Ht 1m2 to 5cm by 15 degreeK in 50 x 1000s .................  ;  27.5    J.s.m-2

............................................................;  27.5      W.m-2

That is, to a simple approximation, if the 5cm depth of soil is taken to be
heated uniformly during the day, and cooled uniformly during the night,
the storage term corresponds to a energy influx/outflux of ~ +_30 W.m-2


99: SOIL_SENSORS, Site NCAR, Wed 08-Jul-1998 09:13:14 CDT, Soil cores taken/Trime measurement
At 10:00 7 July a soil core was taken north of the roped-off area
Fresh wt of top 6cm = 173.9g
Placed in oven for two day bake.

During the night, at ~03:00, 8 July, it rained. At 08:30 the morning of 8 July
a test hole was dug. The moisture had penetrated 2-3cm. Below was still dry.

At 09:00 8 July a soil core was taken north of the roped-off area.
Fresh wt of 0 - 3cm = 83.3g
Fresh wt of 3 - 6cm = 88.6g
Placed in oven for two day bake.

At 09:30 a Trime measurement was made.
Moisture = 10.7 %, TDR level = 46.0
Note only the top few cm are moist.
98: LOG, Site NCAR, Wed 08-Jul-1998 08:09:57 CDT, lots of rain last night
There was a thunderstorm about 3:30 last night (it woke us up in the motel!
There are some puddles around the site.

The OU network went down, so we are unable to look at OU data.  Stan is 
working on it.

The ADAMS apparently rebooted themselves during the storm - probably due
to lightning.  I didn't know they would do that!

All sensors appeared to have survived:
1. NCAR Fast t works and shows a 5 degree drop, along with the slow Ts.
2. NCAR kryptons got wet, but dried in 1-2 hours.  Perhaps their offset
   (difference from hygrothermometers) has changed by 0.5 g/m3).
   [Note that their offset is now negative, which may indicate that we
   are using the "scaled" calibration.]
3. Soil sensors record the moistening and increased cold flux into the soil
   as expected.  The soil Ts show a cold pulse during the rain, and then
   settling back to the general nighttime cooling trend.  All this is normal.
   Tony is very glad that he [had the foresight to] reinstalled the sensors
   at site #1 just before this wetting event.  Also note that this site did
   not record the most moistening, so he didn't disturb the soil too much.
97: SOIL_SENSORS, Site NCAR, Tue 07-Jul-1998 16:36:44 CDT, Re-planted Gsoil and Tsoil NCAR1
Examination of Gsoil for the past two week's data indicated that the 
NCAR1 Gsoil values were markedly out of line with all the other G's.
To a lesser extent Tsoil T was also somewhat different.

At 16:15 CDT I dug out the two probes and reinstalled them.
I did not disturb the Msoil probe, although its output too was somewhat
out of line with the other moisture probes.


96: PROPS, Site NCAR, Tue 07-Jul-1998 16:28:24 CDT, flipped 6.5m prop vane
Since flipping the 2m vane worked so well, I've just flipped the 6.5m prop
also.

95: SONICS, Site NCAR, Tue 07-Jul-1998 14:14:13 CDT, wet towel on sonic
In an attempt to figure out why the 9m ati is spiking, I wrapped the boom
with a wet towel about 1400 CDT.  (We hoped that the electronics would be
cooled.)  This did not affect the spiking, but probably disturbed the
krypton humidity measurement.  I'll remove it in another 15 min. or so.

Towel was removed about 15:05.  It was still damp.  I also used a finger 
to wipe a bit of dust off of both U transducers.  I doubt that any of this
made any difference.

94: HYGRO, Site NCAR, Tue 07-Jul-1998 10:59:13 CDT, fine adjustments to RHs
I've just played with the last 3 days of data and find that the ordering of
the RH profiles is improved if 0.6% is added to RH.4.5m and 0.1% is
subtracted from RH.6.5m and 0.2 is added to RH.1.5m.

Also, the T profile is slightly better by subtracting 0.04C from T.6.5m.

93: LOG, Site NCAR, Tue 07-Jul-1998 10:24:47 CDT, photos taken
A panorama of 8 photos was taken during the krypton cleaning climb mentioned
in the previous logbook message.  I'll try to download these to a 
just-to-be-created WWW page on OASIS.

92: KRYPTONS, Site NCAR, Tue 07-Jul-1998 10:23:07 CDT, Cleaned NCAR krypton hygrometers
Steve cleaned the NCAR krypton hygrometer windows with distilled water
around 10:15 CDT.

This changed the voltages from 0.02 to 0.15 for ch 100 and from 0.1 to 0.7
for ch 101, which isn't a huge change, but somewhat better.

91: SOIL_SENSORS, Site NCAR, Tue 07-Jul-1998 09:23:37 CDT, Bulk Density of soil
On Sunday, 5 July a block of soil was dug up from the area immediately to
the north of the roped-off area around the radiation stand. It was noted that
the top several cm were more friable than the deeper soil.
In the trailer the block was whittled down to give roughly rectangular
prisms. One was formed from the top 3 cm and the other from the top 6 cm.
The blocks wereput in Al pans and baked for two days.
On Tuesday, 7 July the blocks were removed from the oven and weighed.
They were then impregnated with wax and their volumes determined by immersion
in water in a graduated vessel.

Top 3cm:   Dry mass = 59.2g,  Volume = 35cm3,  Bulk density = 1.69 g cm-3

Top 6cm:   Dry mass = 120.3g, Volume = 75cm3,  Bulk density = 1.60 g cm-3  
      

90: PROPS, Site NCAR, Tue 07-Jul-1998 09:13:17 CDT, flipped vane on 2m
I just flipped the vane on the 2m prop (the RM Young lettering is now
upside down) to test if the 2 degree difference in wind direction is due
to some asymmetry in the vane.  I could imagine that the vane was slightly
bent (I  off to the left, when viewed upside down from the hub).

We'll look at today's data to see if there was an effect.  Tom points out
that the 1m could be bent instead, so we can try it tomorrow.

87: SOIL_SENSORS, Site NCAR, Sun 05-Jul-1998 11:02:02 CDT, Soil samples taken/Trime measurement made
At 09:00 CST a soil core was taken and a Trime measurement made. 
The data is in Logbook entries 40 and 41


85: RADIATION, Site NCAR, Sat 04-Jul-1998 13:46:49 CDT, Night-time response of Eppley short wave radiometers
It was noted that immediatedly after sunset the response of the incoming
and the outgoing short wave Eppley radiometers indicated negative short wave
radiation fluxes.
To test whether this was an offset due to the Campbell electronics, the input
from the two radiometers were sucessively shorted, with a jumper between pin 1
and pin 2. In each case to apparent output decreased to +_ 0.078 Wm-2
This value of ~ +_ 0.1 Wm-2 is the data system uncertainty.

It is surmised that the indicated negative radiation flux is due to thermal
effects within the Eppley radiometers. The inside junction of the thermopile
views the warm inside of the radiometer case while the other junction 
views the inside of the dome. The thermopile is sensitive to long wave
radiation and so responds to the flux of long wave radiation from the warm
interior of the sensor to the cooler dome.

The artifact is most severe for the first hour after sunset when it corresponds
to ~ 5 Wm-2. Then,throughout the rest of the night, the artifact maintains a
value of ~ 2-3 Wm-2.

As the artifact is common to both upward facing and downward facing radiometers,
the effect should almost cancel when the net radiation flux is calculated.

NOTE The K&Z short wave radiometers responds in a similar fashion
We suspect that the OKMN short wave radiometer data is forced, by software, 
to yield 0.00 Wm -2, whenever its output goes negative.
84: HYGRO, Site NCAR, Sat 04-Jul-1998 11:09:23 CDT, Replacement of 6.5m TRH
Comparisons indicated that the 6.5m TRH was generating questionable T
At 10:45 CDT the inplace TRH was removed from the tower and the new TRH
brought from NCAR on 3 July was installed.
This sensor did not report RH. It was removed and on inspection it was 
discovered to have a bad board connector. This was fixed and the new TRH
reistalled on the tower at 6.5m at 11:25 CDT

At 13:35 CDT changed s/n to 006

52: RADIATION, Site NCAR, Mon 29-Jun-1998 16:44:22 CDT, Adjusted level of NCAR Rnet
Adusted level of net radiometer.  The bubble was touching the edge
of the bullseye and I rotated the radiometer to the east to center it.