AlTiS-NG GUI with Jason-2 mission on the Komadugu river, Niger
AlTiS-NG GUI with Jason-2 mission on the Komadugu river, Niger

AlTiS-NG | visualizing and processing altimetry data

AlTiS-NG | visualizing and processing altimetry data

THEIA Land Waters Expertise consortium
THEIA Scientific Expertise field

Access to software and data

Software Download @GitLab

Presentation

AlTiS-NG (Altimetry Time Series – New Generation) is a software designed for the visualization and processing of altimetry data to create time series of water levels on various bodies of water such as rivers, lakes, and flooded areas.

AlTiS-NG is a new release of the AlTiS software (2019-2024). It has been entirely redeveloped in Rust by the Centre for Topography of Oceans and the Hydrosphere (CTOH), a National Observation Service (SNO) of the LEGOS laboratory. The use of the Rust language significantly enhances the performance and ergonomics of the graphical interface.

This software can process a wide range of official GDR level 2 products from nadir altimetry missions in LRM and SAR modes, provided by CTOH. It is compatible with products from historical missions such as Topex, Jason-1/2/3, Envisat, as well as current missions like Sentinel-6 and SWOT nadir. AlTiS-NG is also an important tool for validating altimetry data using in situ measurements and assessing the consistency between historical mission data and new SWOT observations. It can be customized for various applications, including coastal altimetry and monitoring backscatter over ice-covered lakes.

The interface of AlTiS-NG allows users to:

  • Display numerous altimetric measurement parameters: height, distance between the satellite and the surface, atmospheric and geophysical corrections, backscatter coefficient, and waveform peak width.
  • Calculate the altimetric height of the water and configure the applied corrections.
  • Manually select valid altimetric measurements, facilitated by high-resolution map backgrounds (Google Maps, Sentinel-2, OpenStreetMap, Ersi, etc.).
  • Create time series of water levels.
AlTiS-NG GUI with Jason-2 mission on the Komadugu river, Niger
AlTiS-NG GUI with Jason-2 mission on the Komadugu river, Niger
An example of water surface elevation (WSE) computed using the SAR retracker for the Sentinel-3A mission on the Aruwimi River in the Democratic Republic of the Congo. The top left panel displays the WSE time series with its distribution on the right. The bottom left panel shows the median absolute deviation of the WSE for each cycle, with its corresponding distribution on the right.Altis-NG
An example of water surface elevation (WSE) computed using the SAR  retracker for the Sentinel-3A mission on the Aruwimi River in the  Democratic Republic of the Congo. The top left panel displays the WSE  time series with its distribution on the right. The bottom left panel  shows the median absolute deviation of the WSE for each cycle, with its  corresponding distribution on the right.

With over 100 users worldwide, AlTiS-NG has become an essential tool for many hydrologists. It enables them to easily process time series data on rivers and lakes using over three decades of spatial observations.

AlTiS-NG is free and open-source software. It is multi-platform, compatible with Windows 10/11 and Linux, and its installation is simplified.

Contact

Fabien Blarel
LEGOS | CTOH
ResearchGate

Documentation

Documentation : https://ctoh-docs.sedoo.fr/AlTiS-NG/docs/wiki/AlTiS-NG-Wiki-ia.html

Reference

Frappart, Frédéric & Blarel, Fabien & Fayad, Ibrahim & Bergé-Nguyen, Muriel & Cretaux, J. & Shu, Song & Schregenberger, Joël & Baghdadi, Nicolas. (2021). Evaluation of the Performances of Radar and Lidar Altimetry Missions for Water Level Retrievals in Mountainous Environment: The Case of the Swiss Lakes. Remote Sensing. 13. 2196. 10.3390/rs13112196.

Search