Fig. 2: Water clarity (A) during and after COVID-induced closure period and (B) as a function of total visitors to the Hanauma Bay Nature Preserve, O‘ahu, Hawai‘i per day.
From: COVID-19 anthropause affects coral reef ecosystems through biophysical changes

Clarity was quantified by horizontal visual reading of the Secchi disc just below the water surface. In A, Points are jittered along the x-axis to improve visibility. In B, gray shading represents the 95% confidence interval. Zero values on the x-axis reflect days when the bay was closed during the COVID period.