River channel / floodplain connectivity

Satellite(s) e.g., Jason-2.	Monitoring element Water surface height.

Satellite(s)

e.g., Jason-2.

Monitoring element

Water surface height.

Description technique

Park (2020) employs the concurrent measurement of water levels over river and floodplain and analyses seasonal changes in water surface height differences between the two water bodies. Hydrological connectivity thresholds at different stages during the rising phase are then identified and validated using field data and remote sensing-driven surface suspended sediment maps.

Accuracy / Resolution

Root mean square error (RMSE): 0.6-2.1 m.

Case study

Amazon River.

Benefits

Decoupling the two indiscrete flooding processes during the rising phase: channelized and overbank processes is one of the major outcomes of this study.
The proposed approach is relatively straightforward to be used, and therefore it may be readily adapted by non-remote sensing experts.

Limitations

Altimetry data is available only at the intersection with the satellite pass and not during the dry season.
Detailed mapping of flow routing patterns and sedimentation patterns in the floodplain, and how they influence floodplain landscape development still have to

Applicability for Northland

Yes, possibly depending on availability of satellite imagery, in-situ data and characteristics of river of interest.

Publication references

Park E. 2020. Characterizing channel-floodplain connectivity using satellite altimetry: Mechanism, hydrogeomorphic control, and sediment budget. Remote Sensing of Environment. 243:111783. doi:10.1016/j.rse.2020.111783.

https://repository.nie.edu.sg/handle/10497/22057

Other comments or information

One of the promising alternatives to altimetric data would be integrating Interferometric Synthetic Aperture Radar (InSAR) techniques that can map floodplain water surface gradients.

Other references

Schwatke, C., Dettmering, D., Bosch, W., Seitz, F., 2015. DAHITI–an innovative approach for estimating water level time series over inland waters using multi-mission satellite altimetry. Hydrol. Earth Syst. Sci. 19, 4345–4364.

https://hess.copernicus.org/articles/19/4345/2015/