“Rime ice forms when super-cooled water liquid droplets freeze onto surfaces. Meteorologists distinguish between three basic types of ice forming on vertical and horizontal surfaces by deposition of super-cooled water droplets. Of course there are also intermediate formations, whereas, hoar frost (refers to white ice crystals deposited on the ground or loosely attached to exposed objects, such as wires or leaves. They form on cold, clear nights when conditions are such that heat radiates out to the open air faster than it can be replaced from nearby sources, such as wind or warm objects. Under suitable circumstances, objects cool to below the frost point of the surrounding air, well below the freezing point of water. Such freezing may be promoted by effects such as flood frost or frost pocket. These occur when ground-level radiation losses cool air until it flows downhill and accumulates in pockets of very cold air in valleys and hollows. Hoar frost may freeze in such low-lying cold air even when the air temperature a few feet above ground is well above freezing.” according to Wikipedia
Weather Online UK states that, “Rime is denser and harder than hoar frost, but lighter, softer, and less transparent than glaze.” This may be the reason why the last week’s winter wonderland did not behave like hoar frost. If the tree branches were tapped, the “hoar frost” did not fall to the ground, the “rime” held on for six days. On average, hoar frost will appear in the mornings, and usually disappear by noon when the wind picks up or the sun warms up the temperature of the air.
” Rime ice, formed from supercooled fog (water droplets that remain below freezing until they have a surface on which to freeze), is an accumulation of granular ice tufts on the windward side of exposed objects. These ice needles, about 2 inches (5 centimeters) long, point into the direction from which the wind was blowing during the fog…Generally the ‘feathers’ and ‘tails’ point into the wind, but under calm conditions the ‘needles’ might grow into every direction. This is why they can be mistaken as hoar frost. However, unlike hoar frost rime is formed by freezing fog or cloud droplets. ,” according to OpenSky which is the home for NCAR/UCAR research. It is true that at the afforestation areas this past week, the trees were showing rime ice formed on the south east sides, which tells the tail that the wind was blowing from the south east during the last few foggy days!!!
The trees situated within the cover of the forest were not as heavily coated as those trees on the southeast perimeter.
Well, whatever the phenomenon, the last week was indeed spectacular with the rime ice on the trees!
For more information:
P4G Saskatoon North Partnership for Growth The P4G consists of the Cities of Saskatoon, Warman, and Martensville, the Town of Osler and the Rural Municipality of Corman Park; planning for areas around the afforestation area and West Swale outside of Saskatoon city limits
Richard St. Barbe Baker Afforestation Area is located in Saskatoon, Saskatchewan, Canada north of Cedar Villa Road, within city limits, in the furthest south west area of the city. 52° 06′ 106° 45′
Part SE 23-36-6 – Afforestation Area – 241 Township Road 362-A
Part SE 23-36-6 – SW Off-Leash Recreation Area (Richard St. Barbe Baker Afforestation Area ) – 355 Township Road 362-A
S ½ 22-36-6 Richard St. Barbe Baker Afforestation Area (West of SW OLRA) – 467 Township Road 362-A
NE 21-36-6 “George Genereux” Afforestation Area – 133 Range Road 3063
Wikimapia Map: type in Richard St. Barbe Baker Afforestation Area
Google Maps South West Off Leash area location pin at parking lot
Web page: https://stbarbebaker.wordpress.com
Where is the Richard St. Barbe Baker Afforestation Area? with map
Where is the George Genereux Urban Regional Park (Afforestation Area)? with map
Contact the Meewasin Valley Authority at 402 Third Avenue South Saskatoon, SK S7K 3G5 Saskatoon, Saskatchewan, Canada. The MVA has begun a Richard St. Barbe Baker Afforestation Area trust fund. If you wish to support the afforestation area with your donation, write a cheque to the “Meewasin Valley Authority Richard St. Barbe Baker Afforestation Area trust fund (MVA RSBBAA trust fund)”. Please and thank you!
Please contemplate joining the SOS Elms coalition or make a donation to SOS Elms ~ leave a message to support the afforestation area 😉
“I believed that God has lent us the Earth. It belongs as much to those who come after us as to us, and it ill behooves us by anything we do or neglect, to deprive them of benefits which are in our power to bequeath.” Richard St. Barbe Baker