week 12


This week, we're exploring coastal erosion and how it affects communities globally. Many of the examples and tools we discussed—such as NOAA's Sea Level Rise Viewer and the USGS Coastal Change Portal—are designed for coastal countries, particularly the US. What about where I'm from, though, Nepal? We're a landlocked country, so we don't have any ocean coastline at all. So, by definition, Nepal doesn't really have coastal erosion like you would typically find elsewhere. But that doesn't mean that we're entirely erosion-hazard free.


Actually, erosion itself is an environmental dilemma in Nepal, just of a different kind. Rather than along coastlines, we have erosion of riverbanks, landslides, and even glacier lake outburst floods (GLOFs)—all of which climate change, uncontrolled development, and forest loss are exacerbating.

Riverbank Erosion in the Terai

The Terai region in southern Nepal is threatened by riverbank erosion, particularly in monsoon season. The Koshi, Gandaki, and Karnali rivers swell with monsoon rain and tend to change their path and destroy homes, agricultural lands, and highways. Villagers along the Koshi River perpetually fear flood and erosion, as history has shown that the river can change its course drastically. Such events result in displacing thousands of residents annually and disrupt local economies that rely on agriculture.Landslides in Hills and Mountains

Landslides pose a significant risk in hilly and mountainous areas. Heavy rainfall, deforestation, unplanned road development, and earthquakes often cause them. If soil becomes destabilized, slopes can give way and sweep houses and transport routes away. The frequency of landslides has increased in recent years because of altered weather cycles and improper land use. During June to September, landslides rank as one of Nepal's deadliest natural disasters.

Glacial Lake Outburst Floods (GLOFs) of the Himalayas

As is the case with global warming, Himalayan glaciers are melting rapidly, forming glacier lakes that tend to be dammed by loose rock or uneven ice. The lakes easily burst and let out massive amounts of water that flow downvalley  at destructive speeds. Such events, known as Glacial Lake Outburst Floods (GLOFs), can wreck villages, agricultural land, and infrastructure within minutes. The danger is mounting as Nepal is warming at speeds higher than the global average, particularly at higher elevations.

Though Nepal doesn't have to fear coastal erosion as nations that share ocean borders do, we remain extremely susceptible to erosion-related disasters. Riverbank erosion, landslides, and GLOFs pose threats to life, ravage land, and affect whole communities. Knowing about these hazards is key to preparedness and environmental conservation. Ultimately, erosion is not an exclusively "coastal" issue—it's a climate and land use issue that impacts landscapes of all types, including those in Nepal.




International Centre for Integrated Mountain Development (ICIMOD). Understanding GLOFs.


United Nations Office for Disaster Risk Reduction (UNDRR). Nepal Disaster Risk Profile. https://www.undrr.org The Kathmandu Post. Riverbank erosion displaces hundreds in Terai. National Disaster Risk Reduction and Management Authority of Nepal. https://www.ndrrma.gov.np

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