News - Wayne RESA
Update to Secchi Disk Water Transparency Protocol and Data Entry
The Secchi Disk Water Transparency protocol has been updated to improve accuracy and consistency in Secchi Disk water transparency measurements. Secchi disk water transparency depth is now measured from the water surface to the depth at which the Secchi disk is no longer visible, and values must be recorded in meters (not centimeters). This update corrects an issue in the previous Secchi Disk Water Transparency GLOBE protocol, which measured the distance from the observer rather than from the water surface. That approach often led to measurement errors.
To ensure accurate data collection under the updated protocol, please review the revised Secchi Disk Transparency Protocol Field Guide or complete the Water Transparency – Using a Secchi Disk eTraining.
Because of this change, Water Transparency Secchi disk depth data collected in 2026 cannot be directly compared to data collected in 2025 or earlier. The GLOBE Implementation Office STEPE team is developing a curated water transparency dataset and documenting these protocol improvements in the Data Users Guide. Both resources will be shared in February.
The Data Entry System has also been updated to reflect these changes, as shown in the image below.