Marine remote sensing toolkit

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BRG The University of Queensland
Fundamentals

- Main page
- Pre-processing
- Field data collection
  - Benthic sampling
  - Spectral libraries
  - Optical water properties
  - Bathymetry
  - Control points
  - Features mapping
- Mapping approaches
- Change and trends
- Delivery

# Natural control points

Natural Control Points:

- are used to georeference optical remote sensed imagery (see geometric corrections).
- are features (e.g. coral bommie) that are identifiable in the field and in the image and did not change in position, between the time of image and field data acquisition. Georeferencing used to improve image position and reduce mis-registration between field and image data.
- need to cover spatial extent of the study area (e.g. image and its reef)
- can be measured with GPS or Differential GPS depending on availability

Natural control points distributed throughout the extent of the satellite image.
GPS in dry back located on top of natural control points while recording the coordinates for a 5 min interval.
Position of GPS plotted on top of the same natural control point visible in the high spatial resolution satellite image (Quickbird 2, with 2.4 m x 2.4 m pixel size)