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~10:00 Steve S. just replaced the battery at soil.b.  V went from 11.3 to 13.2, but it is dropping a bit.

~10:30 to 12:30  Spent time replacing the batteries at rad, soila and soila2 with one large battery.

I noted yesterday that an extension cord going to pond had been chewed on (a bit of copper was showing).  Since it was raining, decided not to do anything then.  Taped over it this morning (unplugged cable, taped, plugged back in) from 09:02-09:14.

During this process, I note that Vdsm went from 12.4 (plugged in) to 11.9 (just battery).  This tells me that the power supply voltage that charges the battery is a bit low.  I went back to check if this power supply voltage could be adjusted, but it can't (at least without taking the supply apart, which I didn't want to do because it is quite hot).  It has been running for weeks like this, so I would expect it to keep running.

Weather: Clear skies this morning, possible showers in the afternoon

Summary:  Tsoil.a at 4.4cm bad, low batteries on rad, soil.a2, and soil.b. EC150 & Licor 43.9m

had some events last night. Qsoil.a to be monitored.

Sonics: ok

TRH, P: ok

Wind Speed & Dir: ok

Soil, Rainr: ok, low batteries and tsoil.a 4.4cm bad. Minor precipitation activity during the night.

                  Qsoil.a showing suspicious activity since yesterday morning.

Vmote (rad, a, a2, b): 11.5, 11.9, 11.5, 11.2.

Radiation, Wetness: ok

H2O, CO2:ok, EC150 & 43.9m Licor had some strange action last night, ~3:00 to 7:00.

System (GPS, Vdsm): ok

Pond: ok

Averaged the GPS latitude, longitude and altitude for Jun 12 00-08Z, an arbitrary choice of time.

Note the altitudes are not very accurate, especially lower on the tower. Can't imagine that there is an altitude difference of 19 meters between pond and low. A 30 meter difference between pond and high is getting close.

Google map, with terrain overlay and 40 foot contours, indicates the pond site is something like 170 feet altitude = 52 meters.

11:20 - The 13.9m sonic is having problems. I assume it is due to the recent rain. Will monitor.

UPDATE, 11:50 - 13.9m looking good, idiag normal

10:58 - Tsoil.b has been replaced with the new probe Steve O. installed yesterday.  The only good signal from the old probe (Tsoil.1.9cm.a) is 0.15C lower, which indicates that the new probe is <mostly> settled in.  Note that the rain this morning should have helped "heal" the soil as well.

9:25 -  The internet link to the fish hatchery has been acting up so we are doing a test to try and

isolate the cause. Since Gordon had success with lowering the power on the AP24 we decided to

shut it down.

UPDATE, 10:30 : We went through a process of shutting down each interant and checking Paul's link.

There was no improvement. We then shut down the SODAR and again not success. Paul will

call his provider and we will start getting things back on the air.

UPDATE, 10:45 : Everything back on the air

8:00 -   Tsoil.b 0.6cm just failed as the rain started.

Weather: Cloudy, potential rain today

Summary: Tsoil 4.4cm a & b out, tsoil.b 3.1cm questionable. Plan to use new Tsoil at b.

a few rain events from WXT this morning, ~7:00.

Sonics: ok

TRH, P: ok

Wind Speed & Dir: ok

Soil, Rainr: ok, Tsoil 4.4cm a & b out, 3.1cm on tsoil.b questionable, 0.6cm a6 Tsoil b failed

Vmote (rad, a, a2, b): 11.7,12.1,11.7, 12.4

Radiation, Wetness: ok

H2O, CO2: ok

System (GPS, Vdsm): ok

Pond:ok

This morning, I installed our last spare Tsoilx4 at soil.b.  However, I want to give it some time to settle before using it.  So, swapped connections with the old Tsoil.b from 10:50-11:02 (note that the new probe has ID23) to get a baseline difference.  I then went back to the old Tsoilx4.  My plan is to do the real switch tomorrow.

 Decided to make a LAI measurement this morning since there was good cloud cover. While making the measurements the skies started clearing so this data set, 6/23/13, should be used with caution.

Below is a table of when LAI-2000 measurements were taken on the tower.

We have determined that a ~4' black rat snake lives in a crack in the concrete near the back steps of the base trailer.  Completely harmless (if you are not a rodent).

Instructions for LAI-2000 vertical profiles

Sensor Setup

1. Grab the “A” sensor and control unit. Plug sensor into “X” port on the control unit.
2. 2.       Ensure that the sensor head is clean and the 270° view-cap is correctly oriented (such that it blocks the user). If the sensor head is dusty or has fingerprints, use the cleaning supplies in the box to clean (brush, poofer, lens wipes + fluid).
3. Push ON key.
4. Push LOG.
5. Push ENTER to confirm “WHERE” as AABC.
6. Use keys to enter the next increment for the “WHAT” identifier (V1, V2, V3, etc. for vertical profiles). Remember that the ? key must be pushed to enter a letter.

Measurements

1. Gear up. Don’t forget to stretch!
2. Climb to 38 m.
3. Hold the sensor out from the tower. Orient it such that it is not exposed to direct sunlight (e.g. W if morning, E in evening). Note compass direction.
4. Level the sensor (roughly is OK).
5. Push and release the button on the handle to take a measurement. You will hear 2 beeps. If you don’t, it is likely that the sensor is disconnected. Reconnect and try again.
6. Repeat steps 3 – 5 at every flux level. Point sensor in the same compass orientation every time.
7. When done, push BREAK.
8. Push FCT 09 to turn off the control unit.
9. Please log the time, V# and direction in which measurements were taken in a spreadsheet.

Downloading Data

Note: This can wait until the end of the campaign.

1. Install FV2200 software on your computer.
2. Attach the RS-232 port on the LAI-2000 control unit to a computer serial or USB port.
3. LAI-2000: push ON.
4. LAI-2000: push FCT 21. Note number of files.
5. Run the FV2200 executable and click “Acquire”. Follow the on-screen prompts.
6. LAI-2000: when prompted to print files (after FCT 32), enter:
   1. FROM: 1
   2. THRU: [total number of files]
   3. Make sure that data is saved on your computer. If not, you will have to use “saveAs” in FV2200.
   4. Send the data to Glenn Wolfe: gwolfe@umbc.edu, along with the log-book spreadsheet.
   5. Thanks!

Notes

-          Measurements are best done when the sun is low: before 9 AM or after 6 PM. Optimal conditions are a uniform sky (i.e.  all blue or all grey), but this is not essential given that vertical profile does not take long to acquire.

-          Avoid taking measurements in direct sunlight. You can shade the sensor (e.g. with your hand) from directly behind it. The view-cap prevents this region from being included in the measurement.

-          It would be nice to have measurements from multiple directions.

-          If you ever mis-enter a command on the LAI 2000, just push BREAK to start over.

Weather: Partly cloudy

Summary: Tsoil 4.4cm a & b out, tsoil.b 3.1cm questionable. May change batteries on rad and a2. Rain event shown on

rainr.ott at about 20:30 last night.

Sonics: ok

TRH, P: ok

Wind Speed & Dir: ok

Soil, Rainr: ok, Tsoil 4.4cm a & b out, 3.1cm on tsoil.b questionable

Vmote (rad, a, a2, b): 11.8, 12.2, 11.9, 12.7

Radiation, Wetness: ok

H2O, CO2: ok

System (GPS, Vdsm): ok

Pond: ok

I had speculated at this week's Science Meeting that canopy storage (in particular moisture) should be large to balance the surface energy budget.  I've just run a quickee calculation from yesterday (a mostly clear-sky case).  I simply linearly averaged the in-canopy measurements in this calculation.

I get that, at night, the canopy loses heat at about -20 W/m2.  During the morning, the canopy gains heat at up to 50 W/m2.  During the day, there are large changes, but the long-term average is zero, with a tendency for the top of the canopy to heat while keeping moisture constant and the bottom of the canopy to cool while gaining moisture.  To first order, sensible and latent heat storage are about the same (each about half of the total storage) in the night and morning, and equal and opposite during the day.  The average storage over the entire day was 0!  

All of this seems entirely plausible to me, but it this doesn't explain the energy imbalance (not surprising from EBEX).  Guess we'll have to hypothesize horizontal advection...