SHEBA: Site 2 Messages, 80 Entries..

Station 2 was setup today, Tuesday 12-Oct-97.

It is approximately 2 miles south of the ship on rough ice.

The weather is continuing to hold off with low wind, partial sun and thin
stratus cover.  Temps did drop into the -20 range.

TEG / Propane Status
	2 full bottles.
	Removed the vent insulation and cover plate after seeing the
	other stations last night getting too warm inside.

RF / LOS / Remote Console
	Station Data is getting into the packet files, and the remote
	console seems to be working quite well.

Gill Sonic:  ETL asymmetric R2A sonic s/n

TRH:	s/n 4	-18.9C, 83%

Compass/Gill Orientation:
	The electronic compass is oriented with its 'north' point back
	towards the mast as viewed from the hygrothermometer.
	At the present time, this is looking close to due west.
	Elec. Compass reading = 226.85
	   Adjusted for Dec   = 264.45  (ie declination = 38 )
		Note difference between this and the hand-held compass:
	Hand compass	      = 275	(with 38 declination)

	The alignment of the gill is oriented with it's 'north'
	axis pointing correctly: essentially north, along/parallel
	with its xarm.   It is within compass accuracy of 90-deg from
	the trh xarm: 275+90 = 5-deg.

Station Orientation:
	The 4-component system is directly south of the station. 
	The sled is pointing toward the station and about 10-m to the
	ESE.  The sun shadows will be longer from there but
	the scientific need is to obtain the maximum readings which will
	be more likely from due south.

Logger / 4-Comp.:	s/n 3
	Rad. Level: x=.84, y=.94
	We didn't attempt to correct these readings or confirm them
	with the bubble level in order to not disturb the snow.
	Visually these numbers seemed reasonable. 
	We used conduit to put the surface cables up most of the
	sawhorse leg.

Station 2 was visited 10/19 at about 14:30AKDT

The beacon was replaced
Configuration format 0050 with a new compass scaling, and increased
poll rate for the TRH was installed.
Data Downloaded.
TEG Vent plate re-installed to prevent snow/ice blowing into the box.
Trail Marking was improved.

4-Comp. system domes had a slight bit of ice which was removed.
Note the PYG's look like there is an open.

The data from the PYG's on the 4-comp system appear bad.

From the signature, they're following the PSP values.  This
can happen within the Campbell Mux. if a channel which
is being sampled has an open connection.....check for this
during the next visit.

Gordon and I went out to station 2 this afternoon to
work on the 4-component system. Based on what little
testing we could do, the interface from the pygs to the
10X is questionable. Decided to bring in the 4-component
unit to test in the room and install at station 4. So at
the moment station 2 does not have radiation data.
  A new configuration was also loaded. Refer to message
57.

Time of visit about 22:00 GMT.
  The 4-comp system was taken back to station 2 yesterday.
It checked out ok. There were 2 problems found: (1) the
CR10 was not multiplexing correctly and (2) the cables for
the PYGS needed to be reversed (end for end). The spare CR10
with the correct rom was mounted.
  The heating fan from station 4 was moved out to 2. A new
heater will be added to the fan at station 4.

  The dome temps at station 2, Cleveland, have taken
a step change of about 15C. This happened at 10:00 GMT.
We may still have a problem with the Campbell or else the
heater unit is working overtime!

  A new lead has open up between here and station 2, Cleveland.
At this time we do not have any means of getting to the site
There may be a long way around but we do not know. The feedback
from experience ice people is do not worry about it. It will
probable close back up in a few days.

CAUTION!!!! Gordon and I had gone out there about 3 days ago with
no obvious sign of this happening. At least we did not know what
to look for.

  Ed, Gordon, and I tried to get to station 2 this
afternoon. There was a possible place to cross the
lead and we hope to try it tomorrow.

  Went to station 2 today to work on the Tdomes, download the
new config, and change propane bottles.

  Propane: We tried turning off both used bottles before switching
to the new ones. There was not enough propane left in the line and
the TEG went down. After putting the new bottles on the TEG started again
in about 2 minutes. The whole procedure took lest then 10 minutes.

  Tdomes: Measured the voltage output on the Tdomes. They were higher
than expected so we put in the original logger box. The Tdomes came
back to normal readings.

 The new config to correct the spiking on TRH was downloaded and the
TRH was reprogammed for interactive continuous mode.

  Jeff and I went out to station 2 this morning to remove the
Campbell. We brought it back to the ship to try and find
any problem with it. I decided to send it back out with the
rnet and licor channels shorted together since they were floating
and may have had an effect on the multiplexer relays. If this 
works then we will do the same thing at all other sites. If it
dosn't work then I will reprogram the CR10X with a longer delay
after the relay switching.

  The Tdomes at Cleveland have gone high again. This occurred
at about 17:00 local time. There was alot of spiking before
they made a final transaction top the high state. Based on this
response, the shorts across net rad and licor may have helped.
Our next test will be to reprogram the logger for a longer
delay time between relay changes.
NOTE: PYGS still tracking PYRS

  Chris and I went out to station 2 to switch the
Campbell and the cables going to the PYGS. Based on
past test, this Campbell gave good PYG.raw data but
bad T.domes. The original Campbell was bad on both.
Hopefully the cable swap will help with the problem.
Time will tell.
NOTE: we had to cross 3 new leads to get to the site.

NO COMMENT!

12/18 ~19:30
	Visited Cleveland.

	To get to Cleveland, crossed two large frozen leads that were not 
	there on the last visit.  Both a couple of hundred meters across.
	For both, once across, had to travel to the right few hundred meters 
	to find next section of trail.

	Crossed other small leads and pressure ridges as well.

	Changed propane and Flashcard.
	Got TEG going.  Changed out battery with fully charged one.  Found 3 
	loose wires in battery compartment.  Wasn't sure where they went or 
	whether they've always been loose, so left them.

	Removed nozzle.  Found it to be clean so reinstalled it.

	BEAR DAMAGE:
		4-component fan missing.  Only black plastic connector at 
			end of its cable remained.
		One pyg cable yanked from the CSI box, partially breaking 
			bulkhead connector.
		Snow temperature and heat flux plate cables hanging down.  
			Wire ties holding up excess cable had been broken.
		TRH intake tube hanging by sensor wires.
		TRH cable yanked off TRH when bear bit cable and pulled it 
			back through beam.  Twist lock ring broken on 
			connector.
		Feather duster, whose handle had been stuck in open top of 
			pipe at center of tripod, was broken.

	Reattached pyg cable.  Pins are fine.  Part of plastic bulkhead 
	connector is missing.

	Tried to bundle up excess snow sensor cables.  HFT cable insulation 
	snapped in the cold.  Loosely bundled up cables.  Cables are still 
	within reach of a fox.

	Replaced TRH with spare.  TRH cable is mangled but works.  Cable 
	connector doesn't lock, but still works.

	Removed remains of feather duster so they wouldn't attract 
	another bear attack.

	Did not have a spare 4-component fan with me so didn't replace the 
	missing one.

	Cleaned heavy frost off sonic with ladder and mitten.  Melted slight 
	frost residue off with fingers.  Sonic heads then clean and dry.

	Cleaned heavy frost off radiometer domes.

	Fresh fox tracks in snow around station.

	Used Rocky laptop to check all variables.  All looked good, with 
	possible exception of sonic variables.

	Fairly new pressure ridge swings around site on N and W sides, coming 
	to within about 150' of station.

	Returned to the ship.  No Cleveland data showing up on Splus plots.  
	Cleveland data looks fine, though, when using eve_console on pampoll 
	laptop.

	Downloaded Flashcard data.  Data only goes through 11/30 (local), 
	though Cleveland was active until 12/10 when its battery died.  Data 
	suspicously stops at 0Z 12/1.  I think Florida's Flashcard did the 
	same thing recently.

12/19 ~18:00gmt
	Used eve_console to talk with Cleveland.  Generator and instruments 
still working, but data acquisition program is not working.  Nothing is being 
stored on the Flashcard.  This explains why Splus is not showing any data 
for Cleveland.
	Attempted to use "stop" and "start" commands, but with each command, 
communications locked up.  Never got prompt back.

12/21-12/22
	Found problem with Cleveland not recording any data.  The program 
file config.dat was corrupted, by the extended power outage, the subsequent 
cold, or the polar bear.  One character was changed from an "L" to an "N", 
causing it to hang at startup.
	Have installed good version of program in spare board with the `
ramdisk on it.  Will swap boards when we can get back to Cleveland, but 
Atlanta must be visited first before it runs out of propane.  Hope for Atlanta 
visit tomorrow, but weather is deteriorating.
	The RF link is too noisy to download the new program from the ship.

12/27 ~
	Visited Cleveland.  Changed propane, bringing back one nearly empty 
and one mostly full tank.  Cleveland was visited not because it was due for 
a propane change, but because its data acquisition program was not running.
	Cleaned heavy frost from sonic with feather duster.  Then melted 
crusty residue with fingers.  (Used ladder for cleaning.)
	Cleaned heavy frost from all 4 radiometer domes.
	Replaced DCOM332 CPU board and adjoining I/O board.  The CPU board 
was replaced because of a possible memory chip problem where one bit of the 
data acquisition file changed, causing the program to hang.  The replacement 
CPU board already had Cleveland's config.dat file loaded into its memory.  
(The I/O board was replaced only because there's a vinyl insulated ribbon 
cable attaching it to the CPU board.  Under extreme cold conditions, it was 
safer to replace them as a pair instead of flexing or removing the ribbon 
cable.)
	Added the 4-port fan that was removed from Florida recently to the 
4-component to replace the missing fan that the bear ripped off.
	Used the Rocky laptop to check that data acquisition system was now 
running.
	Forgot to reconnect 3 loose wires inside battery box.  Two wires are 
a pair used to measure a TEG or battery voltage or current.  From the data, 
I think it must be for i.charge.  I don't know what the third wire is for.

	No new lead activity along route, or noticed around station.
	Sastrugi around site (from storms about 3 weeks ago) is mostly about 
6" high.

1/5 ~20:00gmt
	Visited Cleveland.  Changed propane and flashcard.
	Cleveland was not due for propane, but the CRREL tech needed to go to 
Cleveland, so I did a site visit anyway.  One propane bottle was empty.  The 
other still weighed 50 pounds.
	Reconnected loose wires in battery box.  Sensing of i.charge is now 
correct.
	NO FROST ON WORKING SURFACES OF ANY INSTRUMENTS.  Well, except for the 
PSP domes which were covered with light frost.  But the sun is still below 
the horizon anyway.

	Some light snow has accumulated in depressions and formed small drifts 
since last visit.  This must be from snowfall/drift during the previous couple 
of days.
	No sign of new leads or pressure ridges.

1/17 ~20:00gmt
	Visited Cleveland. Changed propane and flashcard.

	Cleveland had stopped transmitting to ship at 1/16 16:00gmt.  Based on 
	flashcard data, the system was shut down by the battery monitor at 
	that time, even though the battery voltage was at 11.5V and the load 
	should not have been dropped until the battery voltage dropped to 
	10.5V.  Then, at 1/17 18:30gmt, the system started back up by itself, 
	presumably because the TEG had charged the battery back up 
	sufficiently.  The RF link was not reestablished at this time.

	Cleaned moderate frost from radiometer domes.
	Cleaned light frost from sonic heads.

	Changed TEG nozzle.
	Swapped out battery with fully charged one.

	Returned to the ship to find that RF was not working.  Jeff returned
	to the site (~23:45) and replaced the antenna.  One of 4 ground rods 
	was missing.  Site was then able to communicate, though it's not 
	definite that the problem was the antenna, as what would've caused 
	the rod to fall out when nobody was on site?  No animal tracks seen.

	To get to Cleveland, we followed a new, straight flagged route put 
	up by support personnel.

	No new leads or changes in snow conditions.

Went to CLE to clean up after ridge activity. What appears to have happened 
was a lead which had formed under the tripod overturned it onto the radiometer 
arm, submerging the 4-component and freezing over.  Later, this lead ridged, 
bending the radiometer arm and toppling the tripod in the opposite direction, 
toward the sonic arm.  This motion tore the data cables from the eve sled and  
bent the tripod.  The total damage is unknown at this time.  

Retrieved in apparently operational condition were the sonic unit, TRH, data 
logger and eve sled.  The central tripod post and some beams were retrieved.  
The 4-component was recovered.  Shields on the upward side were bent, but
the domes were intact.  The pyranometer dome on the downward side broke
and both shields were bent.

Leads and ridges in the Cleveland area were still active while we were
on site.

2/3 ~22:00gmt
	Visited remains of Cleveland near the cold storage hut here in camp.
	Installed rebuilt TEG burner that had been removed from Atlanta.
	Added one partial tank of propane.
	Plan to test TEG and EVE for day or two.  No cables or instruments 
(other than pressure sensor) attached.

Cleveland sled and data system brought up.
Located side-by-side with Florida.

Initially will have only the CR10 with the 4-component system for
testing against Florida for SW domes versus no-domes.
Radiometers installed on 3-legged stand oriented roughly SE.
Sled sitting adjacent to Florida sled roughly SSW of the towers.
NO tsoil, hft, sonic, trh.

Passive weather-head vent. cut into lid of box to help prevent overheating.
Cover on louvered vent is installed.

Sa. 4/4, ~16:00 AKST or 4/5, 1:00 UTC
Added heat motor to open/close a cover plate on the lid vent at Cleveland.
The louvers are covered.  Last night without the heat motor, the box still
got fairly warm ~+25.  The temps at Sheba have been on the warm side.
Will watch to see whether the motor works and whether the box temps stabilize
more.

Su. 4/5, ~9:30 AKDT
Observed heat motor shutter fully opened.
Louvered vent still closed
Noticing that box still getting warm, will add 2nd cable/air access
hole in side of box later.

Installed ATI #3 on Cleveland for check against Fla.

Tower sited immediately to W of Fla tower.  Both sonics pointing N.
ATI boom: 333 + 23 variation
TRH boom:  66 + 23 variation

Notes:
- ATI is approximately .5-m lower than Gill.  Have not measured vertical
distance to snow surface (of today)
- TRH boom sent up was a full length unit, need to cut-off and reinstall
later.
- Clev/Fla sleds to S of towers.

Wind Generator installed to check / mounting.
Could use maybe 2-3' taller mast and braces.
Braces should probably have small pad.
Tolerances on hole for generator head too tight, hard
to put onto mast.
Otherwise mount OK.
Note I didn't see the blinking LED indicating the generator
is producing voltage.  Could be related to single phase rewiring
(unlikely) or charger sensing that battery is fully charged (more
likely).

Now wait for wind (would've been nice a couple of days ago).

Log 4/8 
	14:50 checked generator: turning at ~ 25 RPM in ~14knot winds,
	No voltage output measured on open circuit....wonderful :-(
	Further examination reqd. and check of other unit purchased.

Checked level and made slight correction per bubble level.

Cleveland Logger #4: 

4/10 ~14:30 Installed HFT, and Tsoil sensor at snow/ice interface.
		This is roughly 1.5' under the snow level.

4/10  18:45 AKDT, Programmed CR10 Coefficients
	HFT   = 943149	40.1 Wm**2/mV
	Tsoil = NCAR002 a0 =-236.8619
			a1 = 223.6343
			a2 =  14.91284

NOTE: Good opportunity to intercompare with Fla.
	Both at roughly same depth and ice condition and are within
	~20 feet of each other.
NOTE: Hopefully we will move Cleveland to near a lead tomorrow or
	shortly thereafter.

NOTE: Quick check of the site showing that the Tsoil is not
	working and needs to be rechecked.

4/10 ~15:00 AKDT Removed Clev. 4-comp.
		Reinstalled outter domes
		Left in met-hut while refreshing shot desiccant that's
		used for between the domes.
     ~18:15 AKDT Reinstalled Clev 4-comp.

NOTE: Once again, found snow inside the 4-comp plenums esp. from the
	upwind components.

4/10 ~9:00 AKDT
Wind Generator was running at high speed in am.  Winds at ~6-7m/s
VOC ~= 20
Installed brake: this works
All seemed OK.

4/10 ~11:00 AKDT
	Moved wind generator to Florida to help cover load from
	4-comp heaters.
	Plugged generator into charge controller.
	Iload, Icharge immediately went out to lunch, probably dropped
		in half.  Maybe ground problem.
	Vteg/Vbatt reflecting reasonable values: 17.5, 14.5

NOTE:	After putting onto charge controller later observed unusual
	sounds or pulsing from gen.  Probably feedback from the
	pulse width charging from the morningstar.
	Probably need to connect gen directly to the battery.

4/11 9:30 AKDT
	Tsoil sensor connector at Cleveland had come loose
	after installation.  Reinstalled.  Working.

NOTE:   Fla = -8.5
	Cle = -6.5
	These are very close together, approximately 15-20, both
	were at the ice/snow interface.
	Both had roughly 1.5' of snow over them.
	Coefficients in loggers verified.
	Gsoil for Clev. showing ~2w/m**2 higher (~1 vs 3) positive flux
	so perhaps the ice is thinner and there it actually is warmer.
	Otherwise these numbers seem suspiciously different.

Clev. outter domes reinstalled on 4/11 2:30Z

SWin very consistent between Cle. and Fla.
SWout of Clev. is ~25w/m**2 low.  This could be due to either the
	dome scratch which occured during the station crunch, or
	some antifog we tried to determine whether that would inhibit
	icing (it didn't).

4/12 2:15Z SWout dome on Cle. cleaned with alcohol to try to
	improve the reading vs Fla.
	All domes Fla,Cle,Etl were clean.

4/12 2:20Z
	Reinserted the GPS cable into EVE which had been out.
	With the GPS declanation, and updated orientation.
	the Splus plots should now come out right.

	Confirmed ATI sonic was reporting consistent values on EVE
	for the observed wind.

4/13 18:25Z
Anticipating a trip to Balt when the weather is better, removed ATI
from Clev.

4/16 0z Installed cleaned TEG that came out of Baltimore.
	Installed in-line filter to hopefully help trap-crap.
	Started easily.

4/16 3Z
	Installed wind generator at Clev.
	This is the unit that was wired correctly by the manuf. for
	single phase.
	Works better in all respects than the other unit which was
	mis-wired.  Still have ground plane noise.
	Still need to improve earth ground.

4/16 18Z Removed and set aside for anticipated move to Balt.

4/16 17Z Took down Cleveland station sitting next to Fla.
	near met hut.
	Moved to Seattle site ~.9-1km N of ship.

	Installation totally different than others per Jumper's help.
	He's warning about the meltdown coming within next 1 or so
	months.
	Installed sled on top of 3 4x8' sheets of plywood as ablation
	shield to help keep it from sinking in.
	Installed tripods on top of 6 4x4' sheets of plywood.

	NEED TO: paint plywood white and add white skirting later
	to help protect ice underneath.

	Sonic Installed on 4/18 3:30Z
	Sonic boom height = 136" to center of Gill
		    angle = 337-deg magnetic
	Rad Boom height   = 78"
		    angle = 160-deg magnetic
	TRH boom anble    =  69-deg magnetic
	TRH boom Alignment

Visit_Log

Radiation System
	4/19 22:45Z Cleaned 1/2 dollar size ice off SWin
	4/19 23:30Z - 4/20 4:30	Worked on SW sensors,
		Unable to install Minco heaters on site
		in cold.  Returned to Ship with sensors,
		installed heaters, and got them back
		online by 20:30 AKDT.

4/22 ~18:30
	Seattle: 
		ATI #980303 installed
		Gill #123 removed
		ATI boom height = 114"

	NOTE: the s/n labeled on this sonic conflicts with the electronic
		serial number.
		The number above is the electronic id.

4/22 ~18:00 - 23  Seattle

	SWout outter dome, which was slightly scratched when the Cleveland
	site was crunched, was replaced with new dome.

4/24 17:30-19:00
	Installed new Schroff backplane in Seattle's EVE.  Had John already 
done this?  The backplane I removed was already a Schroff.
	Also replaced the button battery even though old battery was still 
above 3V.

	Data transmission after reinstalling EVE at Seattle did not resume, 
even though data was being stored on RAM and on the Flashdisk.  Killed what 
looked like a hung process on pampoll and issued "start" command under 
entersys while talking to Seattle via RF (which continued to work fine even 
though data was not being sent correctly to the ship).  Data transmission 
resumed.

	No frost on any instruments.

4/25 ~17:00gmt
	Downloaded configuration 54 via RF to Seattle.
	Prior to download, Seattle was reachable via RF, but was not storing 
data on ram or flashcard.  This problem had now happened twice since the 
backplane swap.
	After the download, data was still not being stored.
	I went to Seattle and swapped the EVE box, keeping the A/D board 
since we don't have a spare for that.  Rocky had not been configured with 
configuration 54, so when I loaded config, it went back to 52.
	~20:00, I redownloaded configuration 54 via RF.
	Data is being stored in ram and on flashcard.

4/25 ~18:00gmt
	Swapped EVE boxes at Seattle due to problem with EVE not storing data 
files on either ram or flashdisk.

Jeff and Peter visted Seattle ~2120 - 2210  30 April 1998 GMT

Changed propane  - one bottle empty one had 22 lbs left
Changed flash card
Replaced nozzle - old one looked quite clean.
(John`s cleaning of lines seems to have helped.  

Calibration with Vaisalla wand:
Time = 2149 30 April (GMT)
Tdry (wand) = -17.8   Tdry1 (PAM) = -17.67  Tdry2 (PAM) = -17.78 C
RH (wand) = 70.1      RH(PAM) =  73.8

No icing on radiometers, T/RH intakes, sonics
Fans all operational
Radiometers level according to bubble level
Did not check orientation - no reason to suspect change.

Jeff put A/D board in different slot.
Apparently fixed noisy voltage reading, (Actual voltaqes have been fine)

We had to walk last 100 m due to small lead (1.5 m wide)
that formed yesterday.  Lead was oriented roughly NW-SE.
The lead is where there was an old pressure ridge.
It is well-frozen grey ice.  Closest location to Seattle is ~50 to the`
North.

5/8 AKDT
	Multiple visits to Florida and Seattle.
	First problem was that the U channel on Seattle's sonic was showing 
-99's on eve_console.  Immediate problem proved to be that the sonic was 
frosted up with up to 1/2" of feathery frost.  The U channel returned when 
the frost was removed.
	We used the HEATON command with the TRH and could hear the TRH fan 
slow down, so the sonic heaters are capable of heating still, but must not 
be getting the heat commands from pampoll.  In looking at the output from 
show_heater, it appears that the sensed battery voltage was too low for 
sonic_heater to turn the sonic heaters on.

	Made slight adjustments to Florida's and Seattle's 4-component levels.  
All 4 PAM site 4-components have now been recently leveled with a bubble level.

	The second problem I tried to diagnose was the bad sensing of the 
battery voltage at Seattle.  Swapping Seattle's and Florida's analog cables 
from the battery box to the EVE box made no difference.  Swapping their 
battery boxes made no difference.  It's still too early to say (the problem is 
sporadic) but swapping the EVE analog boards may have fixed the sensing of 
Seattle's battery voltage without having the problem show up at Florida.  But 
Seattle's sensed TEG voltage now jumps around from 14 to 17V.  Not sure if it 
was that way before.

I changed the propane and TEG nozzle at Sea.  Everything else there looked good.

Dave

I was in the area ( at Fla.) and went to check for rime and problems at Sea.  Things looked clean and the right things were making the right noises.

Dave.

Quick visit to Sea. because we had some freezing rain and Fla. needed to be 
cleaned.  Both upward looking radiometers had some melting ice on the domes.  
There was some water droplets on the sonic heads.  We shot the sonic boom at 
113.5  (I think he means 13.5 deg true, ELA).  Some of the plywood near the sled and all the PVC pipe was exposed.  The 
snow was very soft and packs well.  There was some cracks about 150 m south of 
the station. Today was the first recorded positive temp.  0.3C

Hugs
Davey

New fuel at Sea.  The equipment looked good.  It sounded like the spark was 
still sparking.  There are still cracks about 150 m to the south.  The site 
seemed to have moved relative to other equpment in the area and the ship so we 
had the bridge give us a range and bearing ( from the bridge )
RANGE -> 820 meters
BEARING-> 003 degrees

Tdry	0.33 C
Tdry2	0.28 C
RH	100.6  %
digi commpass	279.70 ( w/decl )
boom	13 degrees
flash	14 days ( correct )

Things are getting slushy and wet.  It was drizzling with light winds at the 
site.  Ed found a Swiss Army pocket knife under the radiometers.  ~1130 Alaskan If the data jumped around this time, this is why.  And who's the lucky one to 
get their knife back?

I.B. Wet

The TBox at Sea has been running very high, 45C plus.  I opened the vent behind the PV and cracked the lid on EVE and the Batt Box.  I felt around in eve to
find what was running so hot and the hotest thing I found was the RF
transmitter. When I opened the batt box there was an odor of burnt insulation
and it was warm/hot, too.  I couldn`t tell which component was the warmest.

I.B. Cooler

A lead opened up about 20 feet from radiometer boom.  The lead is about 60 feet
across and 250' long ( just the lake area).  I couldn't spot the ends of the 
lead.  All the plywood is showing. I didn't see any cracks under the station. So
we got lucky.  I was thinking about attaching four 55 gal drums to the tripod 
via a line. The drums will be near the sled and maybe 4 to the sled/box.  That
lead could have easily swallowed the station.  I hope a lot of stress has been 
relieved on that little peice of ice and it won't break up anymore. I got some
killer pictures. 

I. C. Waterfront

Went to check out Sea and level the boom.  I noticed a very fresh crack near 
the tripod. The station was now on a peninsula.  I felt it was time to get a 
second opinion so I called the boys in and they fired up the helicopter. They
did a fly by and we packed it up.  About 2 1/2 hours later it was safe
and sound about half mile away on the other side of the original Sea lead. We
moved it by snow machine.
The plywood is in the met hut and will be painted tomorrow and when everybody is
in agreement we will redeploy.

What does that 'P' stand for again....
D. M. Costa

I would like to welcome you to the new Maui site.  The site is on a nice 
rough peice of real estate located about 3/4 of a mile NW of Atl and 47 degrees,
1090 meters off the bow.  There is a big lead about a 50 m radius going from the N to the E of the site and a 2.5 m pressure ridge that follows the lead about  30 m of the site.  The tripod is on a small hummic/old pressure ridge and there
will soon be lots of melt ponds in the area.
There is also a 2 m icy peak about 10 m west of the site.  
Maui came on line at 0000 GMT JD 162.
All systems NORMAL .... :-D

Mr. Costa

I changed NNW to NNE.  NNW was a mistake and I added a more better topo. ( brain fuzz)

I changed the propane and TEG nozzle. The nozzle was a little bit dirty.

Heights

2.23 m	radiometer from the middle of the boom to the surface
3.02 m	sonic ( middle of the boom to surface )
2.04 m	end of TRH shield to surface 

compass reading will be reported later.

The flash card had days 149-163 ( missing 160 and 161 )

Things looked good .....

I. C. Sun

Leved Maui

x =  0.34
y = -0.01

compass  47.5		Rocky 316.96 ( w/decl )   :-)

I did notice the 6 sec pulse on the TEG current meter.  Everything else was 
great.  

I. C. Ice

The y level at Maui jumped from 0.55 to 2.5 around 1800 on June 22.  We tried 
leveling it today ( @ 1515) and Rocky wasn't recording the changes when we were
adjusting the boom.  I think the level sensor has malfunctioned, so we did the
best we could with the bubble level.

heights
303 cm	middle of the sonic boom to surface
192 cm	end of TRH shield to surface
227 cm	from middle of radiometer to surface

dmc

I went to Maui with Don and Bonnie (PAM station transition people) changed the
 propane, nozzle and flash card.  The instruments
looked clean. 

The TEG nozzle was OK but I switched it for training purposes.  

The flash card had the correct days on it ( 163 - 176 ).

Dave and Christine(PAM computer transition person)

At 1509 local, we checked the levels at Maui with the bubble level.
We leveled the radiometers and discovered that the electronic level
showed Xlevel=-0.15 and Ylevel=0.86 with the bubble level exactly flat.


Hugs

Visited Maui at 1920 UTC 980706.

Radiometers:  upwelling SW had ice/frost on it.  It was cleaned.  Leveled the 
radiometers with the bubble level.

Tsoil sensor was 6 inches in the ice in an open groove.  It was not in water, 
thereby explaining the 4 deg C temperature.  It was repositioned on top of the 
ice and covered with about 1 cm of coarse-grained snow (ice?) crystals.  At 
next visit, we will wrap the Tsoil sensor in aluminum foil.
The flux plate had a visible melt crack in the ice, but the plate was not 
visible in the crack.  It is unknown whether it is horizontal or on edge.  
Therefore, we did not try to remove it or move it.  

Photographs were taken of the Tsoil and flux plate melt cracks, as well as the 
Maui site.

Visited Maui at 1830 UTC 980707.

Radiometers:  All OK.  Leveled the radiometers with the bubble level.

Wrapped Tsoil sensor in Al foil and repositioned on top of the 
ice and covered with about 1 cm of coarse-grained snow (ice?) crystals.  The 
flux plate had a visible melt crack in the ice, but the plate was not 
visible in the crack.  It is unknown whether it is horizontal or on edge.  
Therefore, we did not try to remove it or move it.  

Propane and flashcard replaced.

Made height and angle measurements:
Heights:
Sonic - snow: 123 inches
Radiometer domes-snow: 65 inches

Angles:
Radiometer arm: 219 deg T (22 deg declination)
Compass arm:123 deg T
Sonic arm:36 deg T
Sled-sonic angle: 335-347 deg T

Site visit to maui 7/14/98

	Site visit to reset radiometer levels at maui -- Maui's y level
seems stuck at 2.5.  Only the hundredths digit changed, no matter how
much radiometer was moved.  Maui is now level with buble level.  Fixed
fans on both of the down looking radiometers.

	All else looks well.  

Site visit Maui -- July 23, 1998, 2230-2330 UTC
Moderate-dense fog, light wind.

	Sled on 3ft high pedestal which has become shorter and narrower than theplywood under the sled.  Sled tipping precariously on arrival.  Moved plywood 
and sled over center of pedestal, and will return with material to stake sled 
and plywood to pedestal and protect the sides of the pedestal.  Meltponds cover 
70% of area around Maui, including entire area between sled and tripod. However, radiometers looking at only substantial piece of white ice near tripod, so will only be seeing the meltponds out at larger angles to the vertical.  Likely 
means that the albedo measurements are unrepresentative of the area. Tripod legs starting to get pedestals under them, making radiometer cantilever arm tilting sharply away from main tripod.  Photos taken of site. 

Both the Gsoil and Tsoil have melted down into narrow crevices in the ice.  Couldn`t see either one, so don't know if the flux plate was tilted or not.  Did not dig them out, since we didn't have an ice axe and I didn't want to risk 
damaging them with a coarser tool. Photos taken of Tsoil and Gsoil crevices.

The radiometers had fog/water drops on all domes, with more on the upward 
facing ones.  Radiometer cantilever legs were adjusted so arm wasn't tilted, and radiometers then leveled and cleaned. The rest of the cantilever footpads were screwed into the underlying plywood.  

Propane tanks and flashcard were swapped.

Heights:
              Sonic arm centerline to ice surface: 324 cm
              Downward looking radiometer domes to ice surface: 229 cm

Orientations: Sonic arm: 39 deg T (22.5 deg decl.)
              Compass arm: 129 deg T
              Radiometer arm: 224 deg T

NOTE: Many bear tracks around site.  The bear was observed by many people (including myself) to go up to the Maui site on the evening of July 22, sniff and inspect the tripod, and then decide to move on as Dean, Paul, and Matt approached with snowmobiles.  The bear did not appear to touch anything, and there was no 
evidence that it had.

Site visit Maui -- July 24, 1998

	Repositioned Teg box, and stabilized Teg box and platform with stakes
and rope.  Placed white cloth around platform to protect further erosion
of piller.

Site visit Maui -- July 30, 1998, 2130-2230 GMT
overcast, moderate wind.

	Stopped at site on the way back from Baltimore at 1920 GMT.  Site 
visited due to change in x-level yesterday morning to >6d.  Found
that both tripods had probably slipped forward, also found that radiometer
was missing its leveling marble.  Returned in the afternoon, installed new
leveling marble and raised front leg of rad. tripod to level radiometers.

Both the Gsoil and Tsoil have melted down into narrow crevices in the ice.  Did not try to did Tsoil out.  Dug out Gsiol, it was oriented vertically at 40 cm
depth in wet blue ice.  Wrapped Gsoil in foil, placed on ice with dot pointed
up under 1cm of corse grained snow/ice.  

Propane tanks, TEG nozle, and flashcard were swapped.

Heights:
              Sonic arm centerline to ice surface: 323 cm
              Downward looking radiometer domes to ice surface: 242 cm

Orientations: Sonic arm: 45 deg T (compass set at 22.5d decl.)
              Compass arm: 131 deg T
              Radiometer arm: 228 deg T

Site visit Maui -- August 6, 1998, 2200-00030 UTC

	The radiometer tripod and arm were moved so the radiometers were over a 
meltpond.  The meltpond is about 7-8 m wide and about 10 times as long, with thelong axis running approximtaely E-W.  The radiometer arm is oriented towards 
210 deg T (22.5 deg decl.). The tripod is supported by two guy wires to anchors in the ice(through the ice in one case).  The forward pad of the tripod is at 
the meltpond edge, so this needs to be watched.  The radiometer arm was not 
extended (We were concerned about tipping, but perhaps we should have risked it and extended it a little further -- something to consider).  The radiometer is 
about 170 cm from the edge of the meltpond(i.e., the edge of the top of the ice -- the edge is undercut) and is 227 cm above the water surface.  The edge of themeltpond is about 20 cm high, and the undercut is also about 20 cm.  Using 
T. Horst's formula, I estimate that 70-75% of the radiometer signal is from the 
meltpond, with the remainder from the surrounding ice, ice edge and tripod legs.Leveling of the radiometers is a little tricky.  We accomplished it by putting aladder in the meltpond. When the pond gets more frozen, it will be more 
difficult until the ice is thick enough to stand on.  The pond is 43 cm deep 
(just below my boot tops) and had a thin layer of ice along its downwind (N) 
edge today.  We had 3 ponds to choose from without moving the sled.  This one 
was chosen because 1) it had a dark-blue color, which was the most 
representative in the area. The other ones were a) azure blue and smaller and b)larger and almost black with most of the bottom melted through to the ocean. 
The latter would have been impossible to level and the former will likely freezesolid first and will therefore be less interesting. 

The foil-covered Gsoil plate was put on top of the ice 54 cm from the edge of 
the pond and covered with about 1 cm of coarse-grained ice granules.  The dot 
was facing upwards.


Heights:
              Sonic arm centerline to ice surface: not measured
              Downward looking radiometer domes to water surface: 227 cm

Orientations: Sonic arm: not measured
              Compass arm: not measured
              Radiometer arm: 210 deg T (22.5 deg decl.)

The hand-held Vaisala wand was inserted in the PAM aspirator tube for several 
minutes.  It gave a reading of T = -0.5 deg C and RH=92.6% at 0025-0030 UTC 
August 7.

Photographs were taken of the radiometer installation and the meltpond.

Site visit Maui -- August 7, 1998, 2300-2359 UTC

	Front leg of radiometer tripod raised one notch.  Radiometers leveled. 
Radiometer tripod foot pads were spiked to the ice.

Site visit Maui -- August 10, 1998, 2340-0020 UTC

Foggy, light/moderate wind.  Ice melting.

Changed propane and flashcards.

Leveled radiometers and wiped off water drops off of them (esp SWin).
Tightened guy wires.
The meltpond had no ice on it.
Measurements: Radiometers 50-55 inches (sorry, all we had with us) from ice edge
                          94 inches above the water
                          ice edge is 7.5 inches high above the water
                          width of meltpond estimated as 200-250 inches
 

wand calibration @ 2358-0000 UTC: Twand=0.2 deg C  RH=94.0%
                                  T1=0.39 deg C   RH=101.7%
                                  T2=0.24 deg C

Flux plate had melted down 5 cm into ice, but was oriented approximately 
horizontal.  GBut the foil was coming off, so the foil was replaced and the
plate was repositioned at the surface of the ice (dot up) and covered with a
thin layer of ice granules.

Photos taken

We ( Peter and Dave ) went to Maui to install the new level sensor board and 
the Tsoil probe.
I tried to remove the old level sensor and was able to loosen one of the rusty 
screws and the other one broke my Leatherman.  I'll be back tomorrow with a
bigger screwdriver.

Next was the Tsoil sensor. When I plugged it in, Rocky said the temp was
-241.80C and when it was unplugged the temp was 699C.  It shouldn't take very
long for the probe to settle, should it?  I will try it at Fla. Are there any 
diagnostics I can do here?  I couldn't find a log on what happened to the old
one, what's wrong with it?

I. M. Back 

I tried the "new" Tsoil probe at Fla and it also read -239.10 C. I checked the
the probe connector ( nice RTV job ) and didn't see anything obviously wrong. 
I also looked around for a pin output or some help in the manuals up here, 
nothing more than the calibration report.  Any clues?

I M Soiled

Peter and I took the helo out to Maui and noticed the sled was slightly tilted
from the air.  When we got closer we found a ridge formed near the sled. We 
suspect that activity broke the pedistal from the main flow. The result
was not pretty.  The sled was on the ablation sheid which was on a chunk 
of ice the size of the ablation shield and the whole thing was tipped over
about 30 degrees. The "front" corner of the sled was under and I could see about
3-5 inches in the box.  The 2x4s that Kerry and Ola put around the sled last
rotation saved the sled from sliding off the ablation shields and into the 
black darkness under the icy surface. 
We called in for backup and some helo slings.  Dean, Matt and Paul flew out
and we were able to put some slings around the sled and pull it off the ice
chunk, across some black death ( open water ) and up on to some "safe" ice.
Have no fear, EVE and the battery box were removed before preforming such
a trick manuver.  Then we saved the ablation shield and decided to move the 
sled on the same island as the tripod because of the current ice activity.
There were nice islands in the area but the cables were to short. 
We also moved the radiometers back from the edge beacuse the "shore" was
becoming under cut quite a bit.  The ponds in the area were 90% covered with
~3cm of dark grey ice.  
Tomorrow we will try to get things plugged back in and online.

Your Arctic Movers

After a day and a half of 25 - 30 knot winds with fog/freezing rain/rain we
were able to get back to Maui for the reconstruction.  Maui came back online
August 21 at 15:30.  The reconstruction went smooth and she fired up on the
first try ( again ).  We switched out the level sensor and will calibrate it
against the bubble level next trip because the Y axis wasn't settling.
I checked the Campbell CR10X and did NOT find a resistor between the 4H to 4L.
The wiring for the REBS T SOIL PRT is as follows:

T Soil        AMP 9 pin    AMP 9 pin    CR10X
                cable      bulkhead
PRT #1 (blu)      1            1          5-H
PRT #2 (wht/blu)  2            2          5-L
PRT #3 (org)      3            3          10K
PRT #4 (wht/org)  4            4          4-H
shield            5            5         shield
-                6-9          6-9          - 

The flux plate wire was apparently damaged when being extracted from the ice
to move the radiometers away from the edge, causing this to fail. The wire
looks repairable.
We plugged in the ATI sonic from Atl and the V axis also failed so I will
proceed with the Gill transplant.
The site is/was still active and a new 2-3 foot high ridge has formed about
10-15 feet east of the TRH sensor.  The ridge runs SSE.  The sled ended up
parallel just to the west and south legs of the tripod.  It was not an ideal 
site for the sled due to its proximity to the sonics, but there was no other
choice without moving the entire station. We felt it was worth the possible
contamination of the sonics data for some wind directions in order to maintain
the continuity of the site.  This site is in a fairly precarious position with 
the sled near a melt pond, the radiometer over a "black hole" and the sonics 
next to a recently active pressure ridge.  However, the data collected from
this site will be representatrive of some typical conditions that were not 
sampled at any other PAM sites or the main camp, which are located on fairly 
hefty, safe floes.  The radiometer pond was half open and the sonic pond was
80% open.  The station will be monitored carefully from the bridge and we will
make helo overpasses (and ask the ice guys to also) whenever possible.
I B Online Again

Peter and I took the helo to service Maui.  The flash card and propane were
swapped.

The melt ponds around the sled were 75% covered with thin wet nilas (.5-3 cm),
the rest open water. The ice directly under the radiomters was dark 
grey about 1-2 cm thick.

heights
328 cm	middle of the sonic boom to surface
261 cm	middle of the TRH boom to surface
231 cm	a peak about 4:30 o'clock 40 cm away,  ( noon would be looking straight
	out of the TRH boom )
244 cm	from middle of radiometer to surface of the WATER (actually thin ice)
087 cm	from the "shore" to a point directly under the radiometers
027 cm	from the top of the "shore" to surface of the WATER
218 cm	middle of the rad boom to surface of the snow
(note the radiometer heights don't add up correctly due to rounding )

compass 343 degrees ( no decl. correction (magnetic) ) 
The TRH/compass were DOA and the fuse was blown.  I replaced the fuse and things
seemed to work for a bit.  The data we are getting back now is erratic. Two of
the pins in the connector looked a little bit suspicious.  I'll
head back out with the pin outs and give it a look when I can.  Did I send back
the only TRH at the end of my last rotation?

The flash card had the correct days on it ( 222 - 238 ) missing 232 because 
stations was offline.

Peter leveled the radiometers and pulled the flux plate up for repair.

Hugs

Dropped by Maui to check out the TRH and compass.  The fuse was blown.  Pin 9
on the connector to the TRH unit was a little corroded.  We replaced the fan
and removed the compass beacuse it was giving erroneous readings.  Do
we have another one on site?  We also switched the TRH unit.  The serial 
number is R4 910001  50Y.  Does the Campbell programm need to be modified?

The fan on the downward-looking pyrgeometer is not working.  However, no
frost or moisture was on the sensor.  The radiometers were level to within 
0.3 degrees using a bubble-level and were not re-adjusted.  The y-axis 
on the built-in electronic level does not work.  The sonic anemometers were
level to within 0.5 degrees and were no-readjusted.

The ice around the Maui floe continues to be active, despite low winds.  
The rubble pile that we observed just in
front of the sonics on the last visit has moved about 5 meters to the east.
Another similar piler is now in the same place in front of the sonics.  The 
area under the radiometers has frozen to about 1-3 cm and there are also small
(2-5) cm chunks of white brash imbedded in the new-ice.  There has been some
finger-rafting of the new ice. 
A major change is
that the pool of water/new ice below the radiometers has been greatly shrank by
the ice movement, thick white ice moving in to with 2 meters of the location 
directly below the radiometers.   Therefore some of the increase (decrease)
in upwelling shortwave (longwave) radiation is due to advection of whiter ice,
rather than is situ freezing, although the latter is also ocurring.
The Maui ice floe itself is about the 
same size, with no apparent ablation around the edges.  The distances from 
the radiometer to the main flow edge are the same as before.

The flux plate was repaired and reinstalled ( dot up ). We will wrap it
in foil during the next visit.

Mrs PAM

I've found the jack to the fan on the board had come off.  I put it back on
and have been running the unit in the PAM room with the compass attached.
The compass was still erroneous data, values from 240 to 300 (when still).
Can I hook it up to a comm port and talk to it using Procomm?  I checked
out the manual, should I open it and have a looks see?  I will have
to hook it up at Fla to confirm it's deadness. 

The TRH unit that was at Maui:
TRH 006
P1110023  50Y
the compass was KVH P/N 01-0177-0015,  S/N  97060186

I found the coefficients for the TRH that's at Maui now.

dmc

Visited Maui 1015 - 1200 and 1445-1455 AKDT

Maui is an small island of ice in a very active region.  During the morning 
the radiometers were over an area of brash ice.  The immediate area (within 
30 m) around Maui is about 50% open water. This drops off to less than 5% 
except in a region running approx NW to SW which is active and has about 30%
open water. There was more ridging right under the sonic tripod and around the 
edges to the left and right of the sonics. Rafting ice depressed the sonic side
of the floe but ridging of the outer tripod leg kept the tripod level. 
Radiometers needed some leveling due to the tipping of the flow, but not too
much.

During the afternoon visit, the floe had rotated about 90% and there was much 
more open water in the immediate region.  Open water under the radiometers.
No further ridging.  This period should provide a unique data set, under
conditions probably never sampled before... 

The electronic compass, TRH and fan are all back on line at Maui.  The compass 
worked much better after I opened it up and poured the water out.  :-)
I asked about opening the electronic compass because it looked like it was still
factory sealed. We were only getting only 1.5 volts at the TRH boom and we 
found some corrosion in the connectors in the sled at the EVE box. Lots of
open sea water in the area and part of that sled was under water a couple 
of weeks ago. So we took out the "extra" cable from the radiometer boom and used
that as the TRH cable and it worked fine.  The TRH at Maui now is the
orginal one, so the coefficients should now be fine.

The one fan is still out, on the radiometers.  It's a tricky fix because they
are over open water now.  If it drifts over some solid ice we will be able to
get at it.

Approx  1630 AKDT
The Tsoil coefficients were changed.  The S/N on the sensor is NCAR002 
so we use the coefficients for S/N  N002.  There wasn`t an exact match 
for the S/N in the email from Claffey/Semmer ( S/N  97002 is close ).

I M Drifting

Changed the flash card, propane and TEG nozzle. The flash card had the correct
number of days ( 238 - 249 ).  The nozzle "head" was 75% covered with 
burnt tar.

The fan on the downward-looking pyrgeometer is still not working.  We're waiting
for some solid ice to form under the sensor. However, no
frost or moisture was on the sensor.  The radiometers were bubble leveled.
Rocky read  x = -0.22, y = -0.69 

We did a calibration with our TRH wand.
The wand read  temp = -1.5, RH = 92.9
Rocky read  Tdry = -1.35 Tdry2 = -1.49,  RH = 101.73

Compass 234 magnetic,  Rocky  136.1  (raw)

Conditions were generally similar to the last visit, a little less open 
water.  There has been some more ice movement, but significant changes to
the small Maui flow itself.
Below the radiometers are several chunks of brash, some new grey ice
and some larger 50 cm thick floes.  Peter made picture survey.

PAMmy

Ed and Scott visited Maui to repair damage done by a curious bear.
The bear visited Maui yesterday, Oct 10 at approx. 14:00 local. We
lost TRH and compass readings.

We pulled the head (tail ?) plate off and found the small (6 pin
I think) connector unplugged and the piggy backed board unplugged.
Plugging these back in solved the problems of no temp, RH and
compass readings. The bear had apparently swatted the long vertical
temp housing, causing it to pop loose and dangle enough to unplug
things. All is OK. We also reinserted the soil temp probe at the
ice/snow layer. The bear had pulled it loose and it was lying on the
surface of the snow.

Ed measured compass as pointing 124 deg magnetic.  Rocky gave the value as
117 deg.

	It appeared from the bridge this morning that there was much more open
water around Maui than yesterday, so Scott and I helicoptered out to evaluate
the situation.
	The lead is now about 100 m wide, runs east-west and starts just north
of the Maui radiometers.  The Maui side of the lead has thin ice about half way
across; the far half of the lead is open water.  The sonics are not well
positioned to sample the flux from this lead, because the winds were easterly
and did not catch much fetch over the open water.  Besides, the entire PAM
station is between the lead and the sonics.  That is, the sonics are exposed
best to southerly and westerly winds.
	Scott plugged in Rocky and found everything working OK.  I measured
the compass heading to be 124 deg magnetic, while Rocky was showing 115 deg.
Maybe this is part of the spread in wind directions between the three
reporting stations that I mentioned in the Daily_Status report.
	With all that new ice just meters from the station, Maui is at some
risk.  If we get any convergence, all that ice could raft up onto Maui's
floe and make retrieving the station a pick and shovel job.  We'll keep or eyes
on it.

THE PERILOUS LIFE OF PAM SLED #2, CHAPTER 4

We saw from the bridge at 9 a.m. today that the lead just north of Maui
had closed and there was now ridging.  The radiometer stand looked out of
place.  So since the weather had calmed down a bit, Scott, Jumper, and I
went by helicopter to investigate.

We found that the very small floe Maui was on had rotated 90 degrees
clockwise and had ridged right under the radiometers.  The weight of the new
ice had depressed the base of the radiometer stand and the sled so that the
feet of the stand and the runners of the sled were in seawater pooled on the
ice.  The main tripod was high and dry on another floe.  There was no
rebuilidng the station in that rubble field, so we took it apart and slung
it back to the ship.

The key at Maui went off at about 1830 GMT on September 20.

Amazingly, we retrieved all the sensors and cables undamamged, although
the PVC pipe carrying the cable was under water.  The only possible
damage may have been to the radiometer stand, which was a little bent.  But
considering that this was the same station eaten by a pressure ridge at
Cleveland, that damage may have already been there.

Scott commented that maybe the helicopter shouldn't deposit this unlucky sled
on the deck of the Des Gros.  Besides its adventure at Cleveland, this sled
had to be moved because of ice motions when it was at Seattle, and was saved
once before from imminent immersion at Maui.

I don't think that the ATI array was bent during the data collection for SHEBA.
As the attached plot shows, the wind speeds generally agreed between Maui and 
Florida before and after the bear visit and just prior to Maui teardown.  
However, Kurt has noticed that v on this sonic now has a 2.5 m/s offset, which
should show up on this plot if it were present.

Furthermore, Kurt noted that the vsamples are now low, but they were still
solidly 20 after the bear visit.  (They were down to 0 the day before
teardown, but this probably is due to riming since usamples and wsamples
also are low - though not 0 - during this period.  Also, open leads close
to the station were noted during this period which would have supplied
moisture for riming.)  (vsamples is shown as the lowest line on this plot,
normalized by 20 to have it fit on scale.)

...Steve Oncley

From horst Wed Feb 17 13:41:56 1999
Subject: Seattle fetch

I am continuing with the evaluation of the sonic tilts and have begun
looking at station 2.  The plot of wind elevation vs azimuth for
Seattle from April 23 - May 30 shows a very prominent deviation for
winds from approximately ENE (the sonic boom pointed to the North).
The data indicate a positive elevation angle (positive vertical
velocity) of 1-2 deg for winds from 60 deg E of N and a negative
elevation angle of 1-2 deg for winds from 75 deg E of N.  This feature
is present throughout the period.  Does anyone recall any obstruction
or terrain feature to account for this?

Tom

From: guestps@ibis.met.nps.navy.mil (Peter S. Guest)
Subject: Re: Seattle fetch
Date: Wed, 17 Feb 1999 14:09:37 -0800 (PST)

Tom,  I was there then.  Unfortunately, I didn't get any close-up
pictures of the Seattle site. Drats! (I took 360 deg pictures of all
the other sites at least once!) I think I actually made it out to the
Seattle site only once, but Jeff Otten went out at least a couple more
times during this period.  There was considerable lead activity; in
fact we tried several times unsuccessfully to  reach the site toward
the end of my stay.  Leads prevented us  from getting there.  I recall
there was a lead fairly close (10- 20 meters?) to the North.  It was
very active and threw up several large chunks of ice.  I think I recall
there was a large mound in about the ENE direction about 15 m away from
the tower, perhaps even closer. I remember because I climbed it to look
for polar bears. I would suspect this is causing the effects you note,
but I can't say for sure without an accurate direction fix from
pictures.

After a closer look, I found a couple of pictures from the ship's
bridge which show the Seattle site in the distance.  There does appear
to be a new ridge to the north and a "bump" just behind and a little to
the  left of Seattle from the bridge perspective.  I think this (bump)
is about ENE from Seattle. Again, the view is not clear so I can't say
for sure, but it does seem to be consistent with my recollections
stated above.  One thing I am sure of is that there was a lot of lead
activity and ridging very close to Seattle and it does not surprise me
that there were some 1-3 degree deviations in vertical wind speed.  I
also know there were no huts or other man-made obstructions that could
be the cause.  Hope this helps....

 -Peter

Date: Wed, 17 Feb 1999 17:14:04 -0500
From: Ed Andreas 
Subject: Re: Seattle fetch

        I've described Seattle several times as a "fortress."  It had broken
ice all around it at various distances.  I was on the ice camp from May 12
through the end of May and found one photo I took of the Seattle PAM site
May 16.  The view is eastward, not northeastward, but there is an obvious
ridge encroaching into the picture from the north, fairly close--within 50
meters.  I'd say this is pretty good evidence that the offset you're seeing
is topographically controlled.

        Peter was on the station just before me, and I shared duty with Dave
Costa.  You might query them, too, for photos.

                                Ed

From horst Wed Feb 17 15:55:45 1999
Subject: RE: seattle fetch

Ed and Peter:

Thanks for the input.  John also recalled the ridge to the north of
Seattle.  His recollection is that the sled was perhaps to the WNW
of the station.  Does that sound right to you?

What is really remarkable to me is the extremely distinct change in the
elevation angle of the wind from +2 deg to -2 deg over only a 10-15 deg
change in wind direction.  A more complete description is roughly

azimuth		elevation
50 deg		0 deg
65 deg		1.5 deg
70 deg		0 deg
75 deg		-2 deg
85 deg		0 deg

Does that seem possible, given the terrain (icescape? help!)?  I
certainly have no other explanation.  I guess that I have spent too
much time collecting data over sites that resemble billiard tables.

Tom

From: "Persson, Ola" 
Subject: RE: seattle fetch
Date: Wed, 17 Feb 1999 16:42:01 -0700

John and I set Seattle up on April 20.  My logbook from that day says that
"320-338 deg true affected by sled". I also have a picture of Seattle on
April 20 towards about 15-20 degrees (assuming the sonic arm is due north)
showing substantial ice rubble/ridges about 40-50 m to the NNE.  As Ed
describes it, Seattle was a "fortress", with extensive ice ridge rubble
especially close to the sonic in the NW through ENE directions (clockwise).
Unfortunately, the picture probably does not show the 65-75 deg sector.  I
did find a slide I got from Dominique showing Seattle from the west.  I'm
not sure if the contrast will be good enough to see details on the opposite
side of the tripod, but once I find a slide projector (they seem to have
been packed for our move), I'll let you know.  

Ola

Date: Thu, 18 Feb 1999 08:34:56 -0500
From: Ed Andreas 
Subject: RE: seattle fetch

        The changes in elevation angle do seem pretty wild, but I have never
done an analysis like yours.  So who knows how to explain it?  I have seem
similary dramatic changes in the drag coefficient with angle of attack over
sea ice.

        A logbook entry (also should be in the PAM electronic long) on May
30 states that the Seattle sled was -36 degrees from head-on to the
sonic--i.e. northwest of the tripod.

                                Ed

Logbook	Date	Site	Comment highlight(s)
Entry	(local)

37	oct 14	2	Setup 2 mile S of ship (ETL R2A sonic sn?; TRH sn 4)
40	oct 15	all	Sonic hts tabulated (345-348 cm to center of array)
52	oct 19	2	New stn config with revised compass scaling, 
			revised TRH polling
56	oct 20	2	Removed radiation sensors
59	oct 21	2	Replaced radiometers and CR10 data logger
84	oct 26	2	New stn config; replaced CR10
92	oct 28	2	Removed CR10!
93	oct 28	2	Stn 4 TRH modified and mounted at Stn 2
108	oct 31	2	Switched CR10, Pyg cables

112	nov 3	2	Unlogged visit to Stn 2?
116	nov 7	2	Routine maintenance
120	nov 11	2	Routine maintenance
124	nov 19	2	Installed 4-port radiometer fan; heavy riming

155	dec 18	2	Repaired bear damage; replaced TRH
173	dec 27	2	Installed 4-port radiometer fan from Fla;
			Replaced EVE CPU board; heavy riming

191	jan 5	2	Routine maintenance; notes frost-free sensors
220	jan 17	2	Routine maintenance; light/moderate frost

258	feb 6	2	Cleveland 0, Ice 1

353	apr 3	2	Cle brought on-line adjacent to Fla
362	apr 6	2	Installed ATI #3; wind generator
370	apr 8	2	Checked and adjusted rad level
373	apr 10	2	Installed HFT and Tsoil sensors
385	apr 11	2	Attached GPS cable
386	apr 11	1,2,4	Sonic heights tabulated
392	apr 13	2	Removed ATI for installation at Bal
399	apr 16	2	Installed refurbished TEG from Bal
400 	apr 16	2	Moved to Sea site; measured hts and azimuths
409	apr 19	2	Added heaters to SW radiometers
417-8	apr 22	2	Swapped Gill #123 for ATI #980303 (electronic id);
			replaced outer dome of SW out
420	apr 24	2	Installed Schroff backplane
425	apr 25	2	Swapped EVE electronics
439	apr 30	2	Routine maintenance; replaced TEG chimney

452	may 8	2	Adjusted rad levels
467	may 17	2	Measured hts and azimuths; also see #470
475	may 19	2	Routine check
480	may 21	1,2,4	Rime check; minimal riming found
489	may 27	2	Cleaned radiometers; measured azimuths
492	may 29	2	Routine maintenance; measured azimuths
495	may 30	all	Tabulation of site characteristics in late May

502	jun 2	2	Routine maintenance
512	jun 6	2	Routine maintenance
517	jun 8	2	Moved about 0.5 mile
520	jun 10	2	Moved to Maui
525	jun 12	2	Measured heights
535	jun 15	2	Leveled radiometers
548	jun 23	2	Leveled radiometers; measured heights
551	jun 25	2	Routine maintenance
555	jun 27	2	Leveled radiometers
562	jun 30	all	Comparison of bubble & electronic levels

571	jul 6	2	Repositioned Tsoil sensor; leveled radiometers
573	jul 7	2	Measured heights and azimuths; wrapped Tsoil in Al foil
579	jul 14	2	Leveled radiometers
			leveled radiometers
595	jul 23	2	Measured heights and azimuths; leveled radiometers
597	jul 24	2	Ablation mitigation
607	jul 30	2	Repositioned Gsoil; measured hts and azimuths

613	aug 4	all	Tabulated offsets of electronic levels
618	aug 6	2	Positioned radiometers over meltpond;
			repositioned Gsoil; measured hts and azimuths
620	aug 7	2	Leveled radiometers
625	aug 10	2	Leveled radiometers; repositioned Gsoil
632	aug 13	2	Tried to remove rad level sensors
641	aug 19	2	Repositioned (rescued) sled, radiometers
644	aug 22	2	Swapped level sensor; data back on line
655	aug 26	2	Leveled radiometers; removed Gsoil for repair;
			measured hts and azimuths
661	aug 30	2	Swapped TRH (R4 910001); installed repaired Gsoil;
			note that sonic level within 0.5 deg;
			repaired TRH 006 but compass bad (log 662)

666	sep 2	2	Reinstalled "original" TRH; changed Tsoil coeff;
			ice ridging under tripod
671	sep 6	2	Routine maintenance; radiometers leveled;
			note that fan on upwelling pyrgeometer not working
680	sep 11	2	Reassembled TRH following bear visit; logbook 681 
692	sep 16	2	Reconaissance visit; measured compass bearing
			notes repositioning Tsoil at snow-ice interface
699	sep 20	2	Dismantled Maui following ice trauma
713	sep 28	all	Summary of site characteristics

Note that `Routine' Maintenance is often more than refueling, swapping
flash card, and de-riming sensors. However, here I am focusing mainly on
sensor maintenance.