Snow is an amazing insulating material. Igloos are a great example of snow's insulating properties. Even in howling winds at 40° below zero, a properly built igloo with a person inside is never colder than 19°F and can be as warm as 60°F when warmed by body heat alone.
Snow is a great insulator because of its molecular structure. When water freezes into ice crystals, air is trapped into its structure. This trapped air makes for excellent insulation.
So how does this pertain to the golf course this winter? Solid ice cover over the turf for extended periods of time (45-120 days) can result in turf damage because the ice traps gasses below the surface and the turf has the potential of suffocating. Over the last two weeks we have noticed a change in the ice conditions on the greens. The layer of ice has become more porous. This is good because porous ice allows for more gas exchange between the soil and air.
The change in ice conditions can be explained by the thermodynamics of the snow above it. Heat flows in only one direction; from a warmer body to a less warm body. When the air temperature moves above freezing, the ice crystals in the snow start pulling in the heat from the surrounding environment. The snow can store a lot of that heat, making anything under the snow warmer than the environment.
I made some observations last week on #15. Below is a photo I took in the middle of #15, a spot I exposed two weeks ago and again two days ago. The ice on this green has become less thick and more porous than what it was two weeks ago. The temperature of the turf surface was 31.4°F. This was 4.7°F warmer than the snow covering it. The snow and ice have insulated surface temperatures enough that the ice is slowly melting and then wicking back up through the dry snow. Like heat, moisture moves from high to low. The melting ice is moving from high concentration at the turf surface to the dry snow, which is of a lower concentration. It is always interesting to see science at work in the field.
Snow is a great insulator because of its molecular structure. When water freezes into ice crystals, air is trapped into its structure. This trapped air makes for excellent insulation.
So how does this pertain to the golf course this winter? Solid ice cover over the turf for extended periods of time (45-120 days) can result in turf damage because the ice traps gasses below the surface and the turf has the potential of suffocating. Over the last two weeks we have noticed a change in the ice conditions on the greens. The layer of ice has become more porous. This is good because porous ice allows for more gas exchange between the soil and air.
The change in ice conditions can be explained by the thermodynamics of the snow above it. Heat flows in only one direction; from a warmer body to a less warm body. When the air temperature moves above freezing, the ice crystals in the snow start pulling in the heat from the surrounding environment. The snow can store a lot of that heat, making anything under the snow warmer than the environment.
I made some observations last week on #15. Below is a photo I took in the middle of #15, a spot I exposed two weeks ago and again two days ago. The ice on this green has become less thick and more porous than what it was two weeks ago. The temperature of the turf surface was 31.4°F. This was 4.7°F warmer than the snow covering it. The snow and ice have insulated surface temperatures enough that the ice is slowly melting and then wicking back up through the dry snow. Like heat, moisture moves from high to low. The melting ice is moving from high concentration at the turf surface to the dry snow, which is of a lower concentration. It is always interesting to see science at work in the field.
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| porous ice from the middle of #15 green |