Showing posts with label GIS. Show all posts
Showing posts with label GIS. Show all posts

Thursday, March 25, 2021

#TBT Red River Delta

Originally published on 2017-03-25

Cross-border riverine issues have long been of interest to me. In 1995, my husband and I visited Assam and even took a rafting trip on one of the Brahmputra's tributaries. In 1998, I had the privilege of going to Tibet, where I traveled along the Yarlung Tsangpo River, as the river is known in its upper reaches.

Last month, the East-West Center in Washington, DC hosted a seminar on The Upstream Superpower: China’s Transboundary River Policies, presented by Dr. Selina Ho of the National University of Singapore. The entire seminar is presented below (apologies for the video quality, but that’s what E-W Center provided):



An audience member raised the issue of the Red River, which flows through China and Vietnam. Naturally, I had to launch ArcMap to create a map. You may see the map of the Red River Delta and find information about how I created the map on the Bahu of Bengal Facebook page.

UNESCO has designated the Red River Delta as a biosphere reserve notable for mangroves and intertidal habitats.

Thursday, May 17, 2018

Kaveri River dispute

The recent MLA election in Karnataka obscured pressing issues such as water. I stepped in to create maps of rivers.

Rivers of India
I champion open principles: open data, open software, and open standards.

Natural Earth is a public domain map dataset that provided data layers for shaded relief, internal administrative boundaries (states),water bodies, waterways, and populated places. The datasets are available at 1:10m, 1:50m, and 1:110 million scales. I chose datasets at 1:10 million, the most detailed that Natural Earth provides.

I processed the layers in QGIS, which is built on top of and is Free and Open Source Software (FOSS). QGIS uses the GNU General Public License (GNU GPL).The Free Software Foundation sponsors the GNU Operating System. FOSS software licenses grant the users rights to modify and re-use software product.
At the India extent, I applied labels for the states. Going on the premise that named waterways are more significant than unnamed waterways, I created separate layers for named and unnamed waterways. The named waterways were portrayed with a thicker line, while the unnamed waterways were portrayed in a lighter blue color and a thinner line. 

I also created separate layers for rivers with a specified width and rivers with an unspecified width.  Those rivers that had a specified width were deemed more important than those that didn't: likewise, they had a thicker line.
Kaveri River

I then selected administrative boundaries for Goa,Karnataka, and Tamil Nadu; saved them to a new layer; and zoomed in on the layer.In addition to labeling the states, I labeled populated places. Natural Earth favors regional significance over population census in selecting populated places. I also selected segments for the Kaveri River (waterways named Kaveri), saved them to a new layer, and styled the layer with a thick blue line.
Sources:

Front Page - Free Software Foundation - working together for free software. (n.d.). Retrieved May 16, 2018, from https://www.fsf.org/
GNU Operating System. (n.d.). Retrieved May 16, 2018, from http://www.gnu.org/
Natural Earth. (n.d.). Retrieved May 16, 2018, from http://www.naturalearthdata.com/
QGIS. (n.d.). Retrieved May 16, 2018, from https://www.qgis.org/en/site/