Submarius started as just a dashboard for diving conditions, but I quickly realized that there is simply no API for water clarity, nor even a simple way to calculate it. Divers call it viz, and it is one of the most consequential factors for a diving experience. So I dove the viz rabbit-hole. I landed on a state-augmented ensemble kalman filter. More details on the /clarity page. My question for the HN audience is if anyone knows of a better way of doing this? There is a ton of satellite data to train on, but a lot of it is messy (clouds read as turbid water, shallow reefs reflect abnormally causing bad readings, etc). Appreciate any feedback on the subject. Enjoy the read!