Developing a web-based seasonal geomorphological monitoring system for Ayeyarwady River basin in Myanmar
Abstract
The Ayeyarwady River and it two main tributaries Chindwin and Upper Ayeyarwady in Myanmar is one of few free-flowing rivers in the South and Southeast Asian region. Ayeyarwady is also the most morphologically active river in the region which are influenced by monsoon induced high water levels and sediment loads. While such a morphologically active river in its natural state provide immense benefits for aquatic biodiversity and ecosystem, it also poses significant risk to riverine villages, urban infrastructure, agricultural lands and ship navigation. The present bottom-up monitoring mechanism is resources intensive and are not suitable for monitoring large rivers such as Ayeyarwady.
A web-based seasonal geomorphological monitoring system called "Dancing Rivers" was developed for Ayeyarwady river basin using Landsat imagery in Google Earth Engine (GEE). Two seasonal composite images were created: Pre-monsoon (Apr - May) and Post-monsoon (Oct to Dec) for the study area. Using Modified Normalized Difference Index (MNDWI), the seasonal composites were classified into land and water pixels. Further, river channel water surface is segregated from other inland water bodies utilizing masks created from Sentinel-1 images. Utilizing change detection method on pre-monsoon and post-monsoon river water surface, erosion, deposition and no change areas were identified. River width change was quantified by estimating lateral changes in the demarcated stream centerlines and bank lines that were derived from the pre and post-monsoon channel masks. A simplified Graphical User Interface (GUI) was developed for the Myanmar stakeholders to access the Dancing Rivers monitoring system. The GUI provides access to both historical geomorphological change as well as the change for the current year (from 1989 to the current 2019). In addition, risk hotspots were produced from the long-term geomorphological change aggregates to classify sections into three risk categories - high, moderate and low. This monitoring system will aid DWIR to assess the river course changes over 2170 km of the river after the end of every monsoon season to plan for river improvements and stabilization activities.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMGC43K1420B
- Keywords:
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- 1622 Earth system modeling;
- GLOBAL CHANGE;
- 1630 Impacts of global change;
- GLOBAL CHANGE;
- 1632 Land cover change;
- GLOBAL CHANGE;
- 1640 Remote sensing;
- GLOBAL CHANGE