Fig 1.
Seafarer citizen scientist and yachtswoman susie goodall with a 30 cm diameter Secchi Disk and Fibreglass tape measure.
Fig 2.
Citizen science Secchi depth versus extracted MODIS-Aqua Level-3 log10(chlorophyll a) data, available at 4 by 4 km resolution.
(A) MODIS-Aqua Level-3 8-day temporal composite log10(chlorophyll a) data. (B) MODIS-Aqua Level-3 1-day temporal composite log10(chlorophyll a) data.
Fig 3.
Seafarer citizen science Secchi depths, Secchi depths estimated from satellite ocean colour data, and the influence of bathymetry or distance from the nearest coast.
(A) Seafarer Secchi depth data and Secchi depth estimated from the MODIS-Aqua Level-3 8-day temporal composite chlorophyll a data, and bathymetry and (B) with distance from the nearest coast; the size and colour of the points are proportional to the bathymetry or the distance from the coast, respectively. The black line originates from a linear regression analysis. (C) Positive and (E) negative residuals for the relationship in Fig 3A. (D) Positive and (F) negative residuals for the relationship in Fig 3B.