Heath Carmody | Beyond Concave Displacement Wave @heathcarmody2867 | Uploaded June 2023 | Updated October 2024, 1 day ago.
From the boat launch above the dam. Observation #5, June 8th, 2023.
I've captured similar effects a few times, but never very well. This was no exception. These events catch me off guard because they usually appear first in the areas I'm not watching. They are easily visible to the naked eye at this distance. I've seen similar effects in some of @pablosdog2808 , @theplanetruth and @wideawake2814 's observations as well. I'll link some videos with similar effects in a comment if I get around to it.
I only capture this phenomenon when there is a strong concave appearance to the water surface (appearing elevated above horizontal). The effect is kind of like moving a magnifying glass across an image. The already 'looming' water gets even more displaced upwards, stretched and warped. It sometimes appears to fold back in on itself.
Some might describe this as a distorted superior mirage of the water surface. That may be the case, but I think more likely that the cause of 'classic' superior mirages involves both upward and downward refraction at different distances, and this is likely no different. The extra displacement is possibly due to a relatively cold air mass moving across the deep part of the lake, that dissipates as it mixes with the warmer air closer to land.
Each 'band' represents a slightly different viewing angle to the water. This is evident later in the video when you see how the first dark band is formed by downward displacement (we are seeing that water from a lower angle). I'll be releasing a few more videos from my first 5 similar observations at this location, and I'll explain more about the bands and displacement - the way I've been starting to understand it.
As for the overall strong upward displacement, my measurements are rough with the distortion of the campground, but give a pretty good idea of the geometry involved. If anything, I think my eye level estimate is a little high. Feel free to challenge me on anything if you can tell me how it makes a difference in the flat vs. globe debate. Like if someone said "The looming limit for the globe is 3x the expected drop, so 3.6x could only happen on a flat plane" then I would try to verify my numbers better.
Final notes: This was the hottest day of the week, hottest time of the day, and I went to the super busy boat launch in the early evening to capture this familiar high upward displacement/compression and distorted concave appearance. I also captured similar effects the first 4 observations here this year, and dozens of observations in the past years.
From the boat launch above the dam. Observation #5, June 8th, 2023.
I've captured similar effects a few times, but never very well. This was no exception. These events catch me off guard because they usually appear first in the areas I'm not watching. They are easily visible to the naked eye at this distance. I've seen similar effects in some of @pablosdog2808 , @theplanetruth and @wideawake2814 's observations as well. I'll link some videos with similar effects in a comment if I get around to it.
I only capture this phenomenon when there is a strong concave appearance to the water surface (appearing elevated above horizontal). The effect is kind of like moving a magnifying glass across an image. The already 'looming' water gets even more displaced upwards, stretched and warped. It sometimes appears to fold back in on itself.
Some might describe this as a distorted superior mirage of the water surface. That may be the case, but I think more likely that the cause of 'classic' superior mirages involves both upward and downward refraction at different distances, and this is likely no different. The extra displacement is possibly due to a relatively cold air mass moving across the deep part of the lake, that dissipates as it mixes with the warmer air closer to land.
Each 'band' represents a slightly different viewing angle to the water. This is evident later in the video when you see how the first dark band is formed by downward displacement (we are seeing that water from a lower angle). I'll be releasing a few more videos from my first 5 similar observations at this location, and I'll explain more about the bands and displacement - the way I've been starting to understand it.
As for the overall strong upward displacement, my measurements are rough with the distortion of the campground, but give a pretty good idea of the geometry involved. If anything, I think my eye level estimate is a little high. Feel free to challenge me on anything if you can tell me how it makes a difference in the flat vs. globe debate. Like if someone said "The looming limit for the globe is 3x the expected drop, so 3.6x could only happen on a flat plane" then I would try to verify my numbers better.
Final notes: This was the hottest day of the week, hottest time of the day, and I went to the super busy boat launch in the early evening to capture this familiar high upward displacement/compression and distorted concave appearance. I also captured similar effects the first 4 observations here this year, and dozens of observations in the past years.
