Snow Revisited

[oksaradt]

In Oklahoma, our weathermen have been telling us that we've had three huge blizzards in Oklahoma History. The first was in 1896. They told us last year that our blizzard that buried cars was a one-in-a-century-blizzard(xmas eve 2009). We repeated that event in early Febuary. This has coined a new term, not "Global Warming", but "Global Chaos." I'm not going to pick sides on global warming. Weather is complicated, especially in Oklahoma where the Jet Stream and Gulf Streams regularly fight it out, and humanity is one filthy animal that has much disregard for it's environment. I'm sure both contributed.

Regardless, I got to take advantage of two great snow storms that came as predicted. This allowed me to run out and placed sources just out in the middle of areas. The snow buried them for me. My scent wasn't there for anyone to claim my dogs followed it to source. While I knew genreral area and sources were present, it was up to the dog to locate and target my sources for me. With quick rewarming a few days after the last snow (It's currently 61F here as I type), young Thorpe got tasked to help me refind teeth I poured out on open soil in the dark.

The day after the last snow, I had four sources to find: A suet cage with small bones in it, the mentioned teeth above (cleaned), an intact bone with good marrow, and a cavity wipe in a suet cage. All were under a minimum of 3 inches of snow, the teeth were under six inches. This second prolem set, I could tell where the snow build drifts, so the other three sources got buried to ground level in existing snow drifts from the last snow and then piled on higher and deeper.

After the dogs worked and made short order of the finds, I measured the temperature at various thermal areas to define why this was so easy. Ground soil was 32.4F at one inch of depth. Snow temperature was 29.2F. Air temperature was a toasty 13F when we worked.
Temperatue affects air pressure. The warmer the temperature, the higher the pressure. Thermodynamics tells us that hot goes to cold. So, scent sources in a warmer environment should diffuse to a cooler environment where the scent becomes available for the dog to find. That's the key. For a dog to find a scent source, the scent must be available to work to the source.

Now, I have to do a little bragging on the almost 15 months old puppy. I dropped a diaper wrapped frozen placenta yesterday in a snow-fed wash that I knew was not part of anyone's drinking supply. The wash looked like a babbling brook with snow banks in the shade and I allowed for about 60 feet of travel. Thorpe got to work it last, so I got to observe both a lab named Maggie and Murphy's scent reactions. My intent was to introduce Thorpe to moving water HRs work doing it the hard way, from downstream. Everyone else had left for the day, so I had all the time in the world to work him through this.
Thorpe one-upped me by first picking up scent about 120 feet downstream. To his credit, he didn't alert, but wanted to crawl into the culvert the water was coming out of. I cajoled him to follow me into the nicer area where I knew he'd get scent up a snow bank. He did, but he is a head-strong boy and went back downstream to a fence then turned back into the stream. I got to see him put his nose down in the water to blow bubbles at all the lulls of the stream. Dogs do this to use the extra scent organ in the roof of their mouth (or so we assume...I just know all my dogs have developed the habit in water work.) Thorpe worked upstream on his own, never indicating on the scent traps that I thought I'd have to move him past. When we got to the source, it had now thawed and the diaper was floating on top of the water with the tissue underneath. Thorpe decided to work his nose down in the water till he bumped the tissue and his eyes got wide. I was worried that he would try to snack on it, but instead he did a playbow in the water. When I asked, "closer", he laid a paw on top of the diaper right over where the tissue was located.

I think the pup might be a keeper. Yes, indeed.


Jim

[tempe507sar]

Hey Jim, we've had tons of snow so a group of local handlers have been kicking around what kind of scent profile would it be for a subject, out walking, lack of proper clothing and shelter, heavy snow storm so no track or trail located. After a week, more the scent of alive or cadaver? How about after two weeks? What are your thoughts...
Karla

[oksaradt]

A lot would depend on the environment the decedent was in when he/she dies. If the person went through extreme hyothermia prior to dying then they might strip their clothes off. Assuming the person is below 38'F, then decomposition is halted until weather changes. If the person seeks shelter prior to dying then again the environment plays a big part.
Let's say the person dies with black pants and black shirt on, but is lying on top of snow. The dark clothes can actually warm the remains when the sun comes out allowing decomposition to begin. Once the body's temperature rises above 38F then decomposition can start. It then becomes a contest between the heat generated by active decomposition and the cold. I have worked cases where the decedent went back and forth from decomposition to frozen and back over and over. The body can begin to show mottling but still be frozen solid. I would say each case is unique. Search management would be smart to do a lot of intel work on the "victim" as far as their experience in cold conditions. mental state, bad habits (did they go into the woods drunk and/or wasted?), are they familiar with the area, do they have favorite places there, were weather conditions such (say a white out) that even the experienced hiker could have gotten disoriented?

Oh, btw, someone really drunk takes longer to start decomposing regardless of environment because they really can be "pickled." A drowning victim takes longer to float when really drunk. I remember one person that was known to have ingested a minimum of 2Litrs of Grain Alcohol before they went swimming. Typically they would have floated in three days with the water temperature available. The body took five days to resurface.

Next search management would need to collect as much weather data for the search area as possible to have both a daily average temperature and temperature extremems. Vass worked up a formula fo surface decomposition where a body will go from tissue to bones when the sum of the AVERAGE daily temperatures reaches 1250C. This comes in handy, especially in the colder climates, to determine how long you can utilize dogs stronger on tissue than skeletal remains. Tissue being easier to work as the scent diffusion travels so much farther, this also can help the handler estimate what sort of grid dimenisions they should work to feel comfortable that their dog will get into scent if it's there.
Knowing the extreme temperatures will let search management decide when the optimum time to search for remains will be. They could always get a large beef roast, leave it outside in a secure aerated area to monitor how long it takes to thaw to 38F when the temperature rises and if it might do so in such time that the dogs can be deployed.

That being said, I've taken frozen placentas and thrown them out into snow banks. The dogs can still work them. I'm fairly sure it's the blood/tissue component still diffusing through the snow. Usually, in such cases, my tissue was colder than the snow as I believe my freezer stays at about 28F. The snow being warmer creates a temperature gradient with the tissue which should also promote scent travel.

For my area, lots of snow is a rarity. We can have cold winters with a maximum of 6 inches of snow that year. When I do get lots of snow, I always experiment to learn.


Soooo, I'd suggest your group become the experts on your environment by experimenting and documenting. Use your dogs as your scent response tools. If they get no scent then walk away, don't talk them into it. I've learned as much from long term scent studies where I'd place a source in a specific environment and let the dogs work the AREA (without focusing on where my experiment was) and observing the dogs. It's pretty easy to note a properly trained HRD dog's response when scent is available. Have another source somewhere else where you feel confident the dog will get scent so that you feel confident that your dog isn't broke and the dog gets to end on a win.

Best information would be to have someone set up the experiment(s) and let other handlers work the area as a double blind. The person that sets up the experiment stays away. Dog handlers, trainers, evaluators, etc. can work the area, use a GPS marker for where they think remains are. They go back to base and report the hit (if any). Stress to those working the problem that there might be remains there OR NOT, that if there are remains there that SCENT MIGHT NOT BE PRESENT, OR they might make a find. ...it's like a real search. *grin* If they can't do it then you don't want them working with you. If no one finds your remains that day then you can run out, take some temperature readings, wind readings, humidity readings, sun observations, vegetation, critter activity, etc. This makes you all better handlers as you learn to be the experts in your area.
I know my environments very well. I wouldn't go work in the Caribean as neither my dogs nor I know how scent works there. In my own area with surrounding states, I feel we can make a valid contribution.

(sorry, did this as a quick reply, so there might be typos)


Hope that helps,

Jim