FLOSSII: Temp_RH Messages: 11 Entries..

  
  4/4/03
  
  the trh's were set up on the penthouse roof on a single sawhorse
to do a sensor intercomparison.
The channels are as follows:
	Main Tower:
		TRH
ch 00	.5m	001	has broken bell
ch 01	1m	206	has broken bell
ch 02	2m	104	has broken bell
ch 03	5m	701 	has broken bell
ch 04	10m	702
ch 05	15m	007 
ch 06	20m	704	replaced fan - no good since before teardown?
ch 07	25m	008 
ch 08	30m	003

ch 09	Sage:	101	disconnected initialy due to lack of inlet tubes 

ch 10	Lake:	502	disconnected initialy due to lack of inlet tubes

ch 11  cal lab  703
ch 12  cal lab	004	has broken bell
ch 13  cal lab  204

About 17 March, the fan at 20m started dying.  Even though we were there last 
Wed-Thursday, we didn't realize this until the tower was too icy to climb.
Thus, this level will remain bad through the rest of the program.  Sorry...

In our ongoing effort to nail down biases in the T/RH profiles, I've swapped
0.5 and 1.0 (recall that this morning I put a "new" sensor in at 1.0, so now
the new one is at 0.5.  Immediately, the RH profile at least developed a +2%
large value at 1.0.  I'll have to get more data to see how the T profile 
changed.  In any case, I think the old 0.5m (new 1.0m) T/RH has some biases.
(Steve's post-cals of these sensors will be critical!)

In an attempt to understand temperature profile (and RH) biases, I've just
put spare T/RHs in at 2m and 1m:
2m: 004 -> 104
1m: 703 -> 001
0.5m still appears to be lower than 1m, which isn't expected.  Thus, I'll 
probably do some more swapping soon.

I'm starting to look at the T/RH aspiration problems.  During the last part
of Dec and early Jan, T.5m sometimes looks okay and sometimes bad as its
fan became more or less effective.  The attached plot shows Rsw.in on the top,
spd on the bottom, and a flag, ib = abs(T.5m-T.2m)>abs(T.10m-T.2m).  ib should
be 0.  On every day during this period, ib was 1 sometime during the daytime
and 1 during the whole daytime period when the wind was calm.

There may be good data during some of this time period, but we'll never be sure.

From ~9:45-10:30, removed inlet tubes and then brushed snow caps off the Gortex
shields from T/RHs at 30, 25, 20, and 15m.

14:40 5m T/RH replaced, 204 removed, ??? installed
15:00 10 m disassembled and an icicle removed from the teflon filter. 
            Reinstalled 10 m
16:25 - 16:30 Removed icicles from teflon filters of 0.5m, 1m, and 2m T/RH

Dean and Larry have noted that the 10m T was a bit (~0.1C) high.  I changed the fan at about 12:45, but this didn't help.  Now, we've just swapped 5m and 10m
and now see that 5m is too high.  Thus, there is a bit of a bias with the sensor
which is now at 5m.  (And the one which was at 5 and now 10 looks a bit low!).

Since the fan I removed appears to have been working, I've put it back in the
cabinet in the trailer.

We swapped the T/RH at 2m on the tower back with the sensor that was pulled
by Kurt 2 weeks ago, since it was reading about 0.2C high.  (The one we just
installed has a new fan (which is quieter than the one we just removed.)

This done about 11:00.

replaced 2m TRH (bad fan on original) Wed, Dec 4th

TRH heights in meters on tower, as measured by SteveS.


 0.5
 1.0
 1.95
 5.0
10.0
15.5
20.25
25.2
30.2