Water quality / small water bodies

Benefits

The use of both high-resolution remote sensing imagery and red-edge portion of the electromagnetic spectrum allow for the monitoring of several water quality parameters in small water areas.

Limitations

• Improvements could be gained from having in-situ measurements the same day than the images.

• A higher number of in-situ measurements and consideration of other water quality parameters may be needed to improve the results of the study.

Applicability for Northland

Yes, likely.

An important limitation would come from the need to acquire high-resolution imagery, which at the moment is not available freely, and would therefore induce monitoring costs.

Techniques applying optical data will be limited in coverage and temporal granularity by the persistent cloud cover in the region, particularly during the winter months. Mature cloud-masking techniques are directly available for open access multispectral data (e.g. Landsat and Sentinel-2). When using commercial data, care must be taken to ensure that there is sufficiently cloud free imagery available, as cloud masking is not as mature and ordering a large volume of imagery to ensure complete cloud free coverage between multiple observations can become cost prohibitive.