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Ice Accretion Pilot

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Cutty Sark Sailor:
Ahem... er... Here're thoughts I've shared with the pilot team, from this first 'experience'.  Admitted, they are random, confused, incoherent, and possibly totally useless... but:

--- Quote ---Background info: for several years, a WFO LMK meteorologist and I have experimented with WebCam visuals of Ice Accretion: onset, progress, and depth ...and it's not simple. So far, based on this first time event, experiment, this setup  is less viable visually, but then the project is NOT purposed for webcams!!

Frozen Events my location are 'usually' mixed precip events, and can be tricky. Heck... very tricky... .
Many of us (out of habit) MAY try to incorporate the Ice reports with our other observations. This is a PITA, and I don't recognize that as the intent of the project.  If my assumption is valid, I'd put more emphasis on this being an 'event' oriented report,  than a 'time related', or 'daily' report. 

Also I think we're attempting to reconcile 4 major areas of concern... Forestry, Infrastructure, Public Safety, and Transportation.  And what I've noted can also affect the SnowPack content numbers we're more familiar with....

Possibly even an "Observer's point, or sense, of Emphasis" toward one or more of the above areas, as tick boxes related to comments, or whatever... based on their knowledge of area and history... .

If I were a Power Company, NWS WFO, EMS person, etc... I'd want to know about 'onset', 'progress', and 'final' ... For overhead utilities, I'd also be concerned about melting (tree spring-back). I think this could correlate into the CCR 'severe weather' report quite well, but with the 'developing' standards incorporated when finalized... yay!

Consider removing specific tree species (Birch) from "impact category guide"...  Some folks may be quite literal, and at my location, I'd never reach a Cat 5, though a warp jump to Cat 8 is possible... heh....

I might also consider, possibly, in the 'cat guide', 'utility cables  begin to sag and stretch'  or similar, even to extent of 'poles / lines damaged or break'.  Perhaps include a measure in the report of how much 'physical' sag, or some similar, approach.

Suggest maintain 'low key' reference the 4" lines, with total of 6 measurements to average, proved too much for this old mind to remember, and trying to write them down, with snow blowing around me, yucch. This is a toughie for some of us, but I'd suggest a single measurement is better than no measurement, certainly!

Now, about that mounting Strap "non-typo":
Some 'metrics', and some suppliers mean  'this half inch strap dia is 1/2". These will NOT fit a 3/4 dowel.  Make sure says for 1/2" i.d. pipe", and maybe it will approach 3/4"  actual strap dia. Or get the oddball supplier's "3/4" and cross fingers. 
Struggling with this, and my 'hardware collection', I  gave up, and used  1" stainless straps (for pipes 3/4" i.d.) which were actually 1.15"  implementing a 'wrapping' around the 3/4" dowel to get it secure!  Annoying at my age.

Feature to Update or correct an entered report or notes, as with other CCR reports?

Will the initial set-up images overwrite with an 'updated' installation & new photos? Or is this designed as an 'event onset', or 'anticipated event' entry, for each event?
Perhaps a 'quick form' at onset, or is this the intent of the 'setup-form' for each event, then followed by the 'event ends' measurements???

Altitude, Lat and Long if no CCR station ID?
Suggest standardize orientation axis of dowel on setup, rather than random notes like 'faces west', or 'points east'...  e.g.: "Rod axis N/S"  (if seasonal dominant wind vector  'E/W').  Recommend use the 'axis' orientation??

Several folks already asking 'why wood', how about a PVC, etc... not every one understands 'standardization'... duh...
I do suspect that the dowel might require a rougher surface, for my location and general events, rather than the sanded or polished surface, and intend to 'grit' up a couple of areas on my 'initial' setup for eval.  Experimenting for surface ice over the years I noticed a 'grained' flat  surface was more consistent than smoother surfaces, and held the Ice better when measuring.

Many of us also concerned with roadways, etc in addition to forest: Currently requires at least two submission forms, or close attention to comments:
Dowel measurement appears irrational when compared to accretion on exposed elevated surfaces.  0.75" Dowel accrued vertical: 0.012" -- horizontal: 0.005", mostly upper and West side of dowl.  Ice at snowboard / other surfaces, as much as 0.15".  In fact, in my report, I accidentaly left out specifics stating 0.14" ice layer (average) in comments incorporate 'horizontal surface depth'

I THINK at the moment, I'd rather see 2 cats on the same form, rather than 2 form reports...
"Dowel"  with it's Horiz & Vert measurements,
and 'also' / or 'only'
'Flat Surface', with 'depth' only. I note over the years that THIS layer, in my environment, is often thicker, and can INCREASE noticeably as snow compacts etc, on UNTREATED surfaces,  whereas accumulating 'snow' on foilage has more of a tendency to 'blow' off, not increasing. It seems to me this increases the threat time for certain categories.  And can dramatically affect the 'SnowPack' measurement and SWE if can't be included in the core samples... .

  ENSURE that caliper .etc.. has reached ambient outside temp!
If 'need' to brush off loose snow... be very gentle, may take your ice accretion with  the snow!
Ice may fall off on contact.
    Ice has turned to slush. Suggest alternate measurement if using caliper.
    Ice layer too thin (weak) for collector surface, measurement device
    Perhaps finished or sealed, or sanded / polished dowel allows accretion to slip off.
    Metal Caliper or Ruler too warm - hasn't reached outdoor ambient temp
    Twisting or too much pressure during measurement

--- End quote ---

Cutty Sark Sailor:
A quick experiment....  (last live image in the initial thread post)

This pilot program data input forms can be tricky if you're an old fart like me, and don't have a full dose of caffeine in the morning, to trigger my remaining grey cells into operation... dammned decimal point insertion tool don't function well without extra caffeine, and I have a tendency to 'mentally' compute the Ice thickness, and enter it, rather than following directions....  ](*,)  ... duh... expecially since my personal focus is on Horizontal surfaces, rather than the '3 dimensional' measurements... I, so far, have never slipped and fell on a icy tree branch, or power line. And NEVER lost control of my vehicle on a round wooden dowel..., after scraping the accretion off it's windshield or defrosting a dowel's door.  Hard to get in 'universal' mode with a narrow brain, ain't it?

But doing it at -25C  #-o
and dredging through snow drifts... no twig measuring for me, and total SWE only on Mondays...

Oh, and great job on your diligence and visual setup =D&gt; =D&gt;
Submission Delayed. Portion of 24hr snow was near liquid and quickly melded with pack. Total snowpack includes 0.1" ice layer on bottom.


Cutty Sark Sailor:
Thanks, Paul...
Yeah, one of the WFO LMK guys and I've been experimenting a couple of years with 'visual', to catch on cam any Ice building... especially onset, and the 'depth'.  It's tricky.  The dowel doesn't seem to 'work' for that, at least with 'natural' wood color, but that dowel method has been experimented with to a greater degree, and more toward utilities and forest damage. 
From my experience, I think I can tell more personally from the 'flat'... for general, It seems that a 'green shaded' surface, as opposed to other tones, indicates the 'accretion' better on a camera both in natural light, and typical IR.  An black surface better simulates 'pavement' response, with it on ground.  A green 'elevated' (or even the black) has proven to be 'freezing imminent', (related to ground surfaces /pavement -- even if no accretion there yet) since it 'cools quicker'. Melting response in sun is very similar in temps below freezing, and 'ground' only lags elevated slightly in time in temps >freezing... depending on sun and wind.... I guess what I'm saying, is an elevated, green, flat surface is both better 'predictor' and indicator, for all except trees.  The Wood (dowel) would probably better show 'tree' response, but I'm doubtful about using natural wood color....(I think needs 'bark' of some shade rather than 'bare' natural)  gonna experiment a bit more if old age, weak mind, will let me... assuming we have more events.
I wouldn't get out of the covers at -25C. 

Hope above not too confusing... not measurable science, just observations, and subjective.


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