After being fogged out at Nisqually Wildlife Refuge Saturday morning, my wife and I switched plans and headed to McLane Creek Wildlife area. We were expecting to see the spawning antics of chum salmon in the creek and were not disappointed.
The surface of the pond was frozen. No wood ducks or mallards today.
and all surfaces: trails, boardwalk, plants were covered with a light glaze of ice. The temperature the night had dropped dramatically (min temp was 18oC at the Oly airport). We were able to observe two interesting icy phenomena: hoar frost and ice flowers. Hoar frost requires clear, cold, calm nights. As the air temperature drops, the air temperature cools below the dew point. As a result, water molecules in the air (water vapor) are deposited (sublimated) as ice crystals directly on a surface. Unlike rime ice, there is no liquid phase (aka, fog) in the formation of hoar frost.
As we hiked, my wife said to keep an eye out for “frost flowers”. These are not true flowers of course. In fact, they are ice crystals that are forced out from the water inside some plants or from the spaces inside wet dead branches by below-freezing temperatures. And in fact, we were fortunate to find a great example of this phenomenon on a small branch that had fallen by the path. The wood of the branch was surrounded by delicate ice threads.
By the time that we returned to our vehicle, the air temperatures were above freezing and these icy beauties had melted. Sic transit gloria mundi...
Steve
The surface of the pond was frozen. No wood ducks or mallards today.
and all surfaces: trails, boardwalk, plants were covered with a light glaze of ice. The temperature the night had dropped dramatically (min temp was 18oC at the Oly airport). We were able to observe two interesting icy phenomena: hoar frost and ice flowers. Hoar frost requires clear, cold, calm nights. As the air temperature drops, the air temperature cools below the dew point. As a result, water molecules in the air (water vapor) are deposited (sublimated) as ice crystals directly on a surface. Unlike rime ice, there is no liquid phase (aka, fog) in the formation of hoar frost.
As we hiked, my wife said to keep an eye out for “frost flowers”. These are not true flowers of course. In fact, they are ice crystals that are forced out from the water inside some plants or from the spaces inside wet dead branches by below-freezing temperatures. And in fact, we were fortunate to find a great example of this phenomenon on a small branch that had fallen by the path. The wood of the branch was surrounded by delicate ice threads.
By the time that we returned to our vehicle, the air temperatures were above freezing and these icy beauties had melted. Sic transit gloria mundi...
Steve
