Increased water evaporation!
- Thread starter Master Zero
- Start date
That is an interesting explanation.
I live in the desert where we have very little humidity and wind is common place and I've never had 50% loss to evaporation. Not even close.
Now, you'll lose a great deal of water when the wind blows if you have spitters or a waterfall of any kind. You would be surprised at how much you lose in a short time if they are running in the wind.
I live in the desert where we have very little humidity and wind is common place and I've never had 50% loss to evaporation. Not even close.
Now, you'll lose a great deal of water when the wind blows if you have spitters or a waterfall of any kind. You would be surprised at how much you lose in a short time if they are running in the wind.
yes but cold air can hold more moisture than warm air.. so it will evaporate more if its dry and cold than if its dry and hot (like a desert)
Cold air can hold more moisture? Sure about that? Think about it; When air - like many other substances - heats up it expands. Humidity ( moisture in air ) is only relevant to density of air. The humidity % is the % of water the air is holding and its out of total capability at that given temp. So the warmer the air the more it can hold. 100% humidly at 20* is less water volume then 100% humidity at 85*. So I think that warmer air can actually hold more moisture.
Alright time to throw in a little explanation. Water evaporation from any body of water is due to several things: Air motion, temperature, and relative humidity. These interactions are normally referred to as vapor pressure.
Air does hold less total water at lower temperatures than at higher temps. As the temperature dropped the air becomes more and more saturated. Until the dew point, the point where the relative humidity is 100% and water precipitates out of the air.
Now the speed of evaporation is dependent upon the layer of air directly above the liquid water. This has a micro-environment where due to evaporation the humidity is very close to 100% regardless of what the ambient atmospheric relative humidity. So the speed of evaporation is directly linked to how fast the gases water moves away from the body of water. So in still air, the lower the relative humidity is the faster water diffuses away from the micro-environment (more sucking power from the outside atmosphere. As diffusion is heat dependent the colder it is the slower it goes (the molecules slow down). An important note to remember is that more liquid water cannot evaporate until there is room for it in the micro-climate directly above it.
Now wind speeds up the process dramatically because it removes the micro-environment directly above the water. This means than the humidity right next to the water is no longer close to 100%. Depending on the speed of the wind it can be almost exactly the same as the ambient environment. This means that there is less restrictions to water evaporating and it diffuses very quickly. It also causes ripples in the water which increases the surface area of active evaporation.
So I imagine in the winter with the colder temperatures also comes more wind and less plant foliage to deflect it. So on one night with a consistent cold wind blowing and low relative humidity it is highly feasible to loose this much water from your pond.
Air does hold less total water at lower temperatures than at higher temps. As the temperature dropped the air becomes more and more saturated. Until the dew point, the point where the relative humidity is 100% and water precipitates out of the air.
Now the speed of evaporation is dependent upon the layer of air directly above the liquid water. This has a micro-environment where due to evaporation the humidity is very close to 100% regardless of what the ambient atmospheric relative humidity. So the speed of evaporation is directly linked to how fast the gases water moves away from the body of water. So in still air, the lower the relative humidity is the faster water diffuses away from the micro-environment (more sucking power from the outside atmosphere. As diffusion is heat dependent the colder it is the slower it goes (the molecules slow down). An important note to remember is that more liquid water cannot evaporate until there is room for it in the micro-climate directly above it.
Now wind speeds up the process dramatically because it removes the micro-environment directly above the water. This means than the humidity right next to the water is no longer close to 100%. Depending on the speed of the wind it can be almost exactly the same as the ambient environment. This means that there is less restrictions to water evaporating and it diffuses very quickly. It also causes ripples in the water which increases the surface area of active evaporation.
So I imagine in the winter with the colder temperatures also comes more wind and less plant foliage to deflect it. So on one night with a consistent cold wind blowing and low relative humidity it is highly feasible to loose this much water from your pond.
But its not hot here, its COLD and dry. We're in the single digits at night this week.
We get winds, still, I don't get that kind of evaporation loss here.
Perhaps Master Zero does get that kind of water loss but I find it hard to believe he would lose that much every day strictly to evaporation.
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We've been having nights in the teens for the past month, I have a 1200gal pond with a small waterfall that runs year round to promote gas exchange. I haven't seen any noticeable evaporation in the past several weeks.
If you're losing 250+ gallons per day, there's got to be something else going on other than evaporation.
If you're losing 250+ gallons per day, there's got to be something else going on other than evaporation.
