Nepal is one of the most-densely populated mountain areas of the world, and is vulnerable to the impact of climate change, earthquakes, landslides and floods, conflict, political instability as well as the coping with changes brought about by infrastructure development, tourism and out-migration.
The project team made a field visit to Dolakha earlier this year, but follow-up fieldwork has been delayed because of the coronavirus lockdown. Using satellite images, remote sensing experts, geographers, economists and anthropologists are tracking land use change in areas like Dolakha.
The district was already feeling the effect of climate change on agriculture, has seen huge investment in hydropower and highways in the past decade, and was at the epicentre of the 12 May 2015 aftershock of magnitude 7.3 that followed the main 7.8 earthquake a month earlier.
“In a nutshell, our preliminary results show that development in the region is highly dynamic and not linear. Urban development is not an end, but a process,” says Karen Seto of the Yale School of Forestry and Environmental Studies and principal investigator of the project.
Combining satellite mapping and on-the-ground research, the group found that human settlements in the Himalaya have seen many cycles of infrastructure development due to factors like disasters, political instability or economic policy.
Seto says although we know more about the big cities, there is not enough data on which towns in Nepal are growing and how fast, and where the vulnerable groups in society are living, especially after the 2015 earthquake.
The population of Himalayan towns and cities has doubled in the past 40 years, and out-migration from rural areas has left farms fallow, and reduced pressure on forests. This demographic shift has had measurable ecological implications with expansion of urban centres along highways, new roads have caused rockslides, adding to the risk.
With the lockdown into its third month in Nepal, there is already significant impact of the return of young migrant workers back to their villages and the drop in tourism on the semi-urban communities in the Himalayan hinterland.
Researchers will be using NASA’s Landsat images at 2.5m resolution as well as recently de-classified military spy satellite images from the 1980s. On the ground, economists and sociologists will collect data on health, education, migration and the impact of political changes on the communities.
Says Seto: “The findings will help local governments understand the changes taking place so they can plan safer urban development less vulnerable to earthquakes, landslides, fires. After all, disasters in the Himalaya are not a question of if, but when.”