‘Average annual temp rose by 0.056 degree Celcius in the past 4 decades’The average annual maximum temperature of the country Nepal has risen by 0.056 degree Celsius, according to a recent study conducted by the Department of Hydrology and Meteorology (DOHM).
Chandan Kumar Mandal
The average annual maximum temperature of the country Nepal has risen by 0.056 degree Celsius, according to a recent study conducted by the Department of Hydrology and Meteorology (DOHM).
Proving the claims of climate change impacts for mountainous country, the study has suggested that the average maximum temperatures in all seasons in Nepal have increased for the period 1971-2014.
The study has shown a positive trend in annual and seasonal countrywide maximum temperature however no such significant trend has been observed in yearly or seasonally precipitation around the country. Likewise, extreme events have also been limited to some particular areas of the country.
The monsoon season has recorded the highest growth of 0.058 Celsius per year and pre-monsoon the lowest of 0.051 Celsius annually, it suggests.
According to the study, except for Bara, Rautahat and Sarlahi, the all 75 districts have witnessed increasing temperature annually as only 72 districts have shown significant trend.
Interestingly, the highest rise in annual temperature of 0.092 degree Celcius was observed in Manang and the lowest of 0.017 degree Celcius in Parsa.
“The low-lying Tarai districts have witnessed the lowest increase in temperatures (0.021 C) and high Himalayan regions the highest (0.086 C),” noted Pratibha Manandhar, senior divisional meteorologist with the DHM and a member of the study team. The highest increase in annual temperature of 0.12 degree Celcius has been recorded in mountainous district of Manang in winter season.
Manandhar credits all these as increasing effects of global warming which also impacts Nepal, a country which contributes less to global cause of global warming.
“The rising population and it has a dramatic effect on our surroundings,” noted Manandhar, adding, “Country like Nepal, which contributes almost nothing to global warming, is bearing the brunt as well.”
According to the report, 28 districts has shown positive trend in monsoon rain whereas 47 districts have shown negative trend.
Most of the districts in the farwestern region and central districts in the western region have shown increase in annual rainfall. Except for the Tarai, all the other regions have recorded a decrease in annual rainfall.
Out of those 47 districts with less annual rainfall, five districts—Manang, Dolakha, Ramechhap, Sindhuli and Ilam—are the most affected.
Monsoon precipitation has gone up in the Tarai, whereas the rainfall during the same season has decreased in the rest of the regions.
An increase in pre-monsoon precipitation has also been traced in the Tarai, Siwaliks and mid-hills, but it has plummeted in high mountains and high Himalayan regions, according to the report. Altogether, the post-monsoon precipitation has shrunk in 73 districts, including the all five regions.
The report has also studied extreme weather patterns in the country.
According to the report, extreme rainfall has been significantly increased in northwestern and northeastern districts of the country.
The number of rainy days with more than 1mm of rainfall has increased, which was more significant in 12 districts. The number of wet days has, however, decreased considerably, mainly in the northern mountain districts, it says.
According to Deputy Director General of the DoHM Sarju Kumar Baidya, high intensity rainfall has been observed in short period over the year—which is abnormal.
“We see heavy rainfall in short period of time. Extreme rainfall has the potential to cause water-induced disasters like floods and landslides,” said Baidya.