Climate change to cause frequent landslides in the Himalayan region, including Nepal, says NASA
Changing rainfall patterns—turning more frequent and intense due to climate change— could trigger an increased number of landslides in Nepal, bordering regions of China and in the higher Himalayan region, according to new research findings of NASA.
The NASA study, which is said to be the first quantitative study of the links between precipitation and landslides in the region, says the rise in landslide events would be significant in the border regions of China and Nepal, recording a surge of 30 percent to 70 percent in the number of landslides.
The research findings, released on Tuesday, looks more alarming because the projected increased number of landslides in the region would take place in areas currently covered by glaciers and glacial lakes, which is already feeling the heat of climate change.
The latest findings only add more evidence of a harsher future for the Himalayan region, which, for long, has been proven to witness adverse impacts of climate change in various sectors.
The finding strongly validates arguments that countries like Nepal are more vulnerable to climate change, said Manjeet Dhakal, a climate change expert and advisor to Least Developed Countries (LDCs) Chair to the United Nations Framework Convention on Climate Change.
“As it clearly mentions climate change as the reason behind more extreme events like landslides, it provides a strong ground for negotiations with international communities and for attribution, where we have always been weak,” Dhakal added.
The study, a collaboration between scientists from NASA’s Goddard Space Flight Center in Greenbelt, Maryland; the National Oceanic and Atmospheric Administration (NOAA) in Washington; and Stanford University in Palo Alto, California, was based on satellite estimates and modelled precipitation data to project how changing rainfall patterns in the region might affect landslide frequency in the region.
The study team had relied on different models for assessing precipitation and landslide trends in the future (2061-2100) versus the past (1961-2000).
The findings of the study are troubling, especially because the landslides in such fragile zones would not be limited to the region alone, its impact would reach downstream communities, with landslides damaging dams and other infrastructures.
“Problems of the mountain would not be a problem of the mountain region alone. This report shows that such effects would have a cascading impact on low-lying communities, by damaging infrastructures and water resources, ” said Dhakal. “This report once again proves that a mountainous country like Nepal is more vulnerable to climate change effects and gives us strong evidence that the developed countries should cut down emissions.”
The Hindukush Himalayan region, which stretches from Afghanistan to Myanmar, is known as a water tower for the region as it meets water needs for the region and millions of people. The region has been facing an accelerated rate of melting of ice and is projected to lose one-third of its ice by the end of the century.
According to a recent study, rising demands and excessive melting of glaciers accelerated by climate change has threatened the region’s water towers, which could pose a risk of water storage for over 1.9 billion people.
Experts worry that the impacts of climate change would be even deadlier for Nepal where the climate resilience and preparedness against the looming mayhem remains poor.
“Our country has not even reached a certain level of understanding about climate change, which has become a climate crisis,” said Madhukar Upadhya, climate change and watershed management expert. “In the last few years, we have witnessed how rainfall patterns have altered and caused massive water-induced disasters.”
In recent years, Nepal has been experiencing changes in rainfall patterns, which is becoming more intense with heavy rainfall within a short span of time, unleashing water-induced disasters in the country.
A government study, “Observed Climate Trend Analysis of Nepal (1971-2014)”, based on the hydro-meteorological data of four decades from the Department of Hydrology and Meteorology, had clearly projected signs of climate change impacts in the country, in the form of increased temperature and changes in rainfall patterns. The study concluded that extreme rainfall has significantly increased in northwestern and northeastern districts of the country.
Another study predicted that Nepal’s climate is likely to get warmer and wetter in the future, indicating an increase in intense rainfall events and temperature increase. It further said while there will be higher intensity rainfall, there will be fewer rainy days.
According to Upadhya, the total loss incurred due to water-induced disasters was
Rs28 billion between 1983-2005 and for the period of 2010-2016, it was Rs16 billion, showing there has been an increase in losses due to extreme weather events.
“The total estimated loss was more than Rs60 billion in 2017, which saw massive floods in Tarai and landslides in the hilly regions. We are incurring economic losses due to climate change,” said Upadhya. “There are changes in rainfall patterns at the same time there are droughts too. Hydropower and our highways which are along major rivers that get flooded every year will continue to be affected due to climate change events. But our preparation is almost nil.”