NavList:

This time I managed to get to the shoreline with my sextant late in the day, when the sun is out over the water (Az ~ 290 deg). I took a series of 18 sights over 20 minutes with the lower limb of the Sun descending from 14d23.8m to 10d16.4m .

I reduced the sights using Henning Umland’s Sight Reduction for the Sun, V1.39 retaining the default temperature and pressure.

https://www.celnav.de/sunsight.htm

The mean of the intercepts was -1 nm and the standard deviation was 2.88 . This suggests that the smoke had little effect on refraction. More practically, the haze made very little contrast between the water and sky and I think this adds to the variability. It was a challenge to bring the sun to the nearly invisible horizon and not be biased by the reflection of the sun off the water. It was a comparison of slightly bluish-grey vs slightly brownish-grey, but mostly just grey! Visibility was less than 2 miles at times (couldn’t see the buoy off shore), so dip-short may also have been a factor.  The sun’s attenuation was so great that the crossed-polarizer index shade was set full open!