Kathmandu – The possibility of extreme air pollution and the risk of forest fire is aliening this winter. Winter precipitation is key to maintaining clean air together with keeping moisture on the ground. But there is no immediate possibility of significant rainfall, according to the Meteorological Forecasting Division of the Department of Hydrology and Meteorology.
This means the atmosphere will not be cleared and the possibility of air pollution being more toxic is high. Dry winter leads to the danger of forest fires, which is also bad for air pollution.
According to a Meteorologist, there is a possibility of less than the median rainfall this winter across the country. ”And also, there is a possibility that the maximum temperature will be higher than the median across the country”. Winter forecast by DHM says, ”minimum temperature will be average or more than average.” However, there was average to more than average rainfall, and the maximum temperature was below average in the winter last year.
Although the country received normal precipitation during the monsoon season, with the end of monsoon there is no significant precipitation. That is what worrying experts and the public regarding air pollution and possible forest fires. ”All indications are leading towards higher air pollution and danger of forest fire-which will add pollution into the atmosphere”, Meteorologist Shanti Kandel said.
According to her, there are no signs of rainfall in the near future. “A few areas of the high mountain will experience isolated snowfall but in mid-hill and flat land, weather will be foggy but there will be no rainfall”, she added. No winter rain yet, neither the immediate possibility may cause increased air pollution in the coming days and flights will be affected because of low visibility and fire incidents in the forest area will increase.
Geographical conditions, weather systems, and local as well as regional activities affect air pollution in Nepal. Air pollution has become a major concern of key urban areas including the Kathmandu Valley during winter for the past few years.
The main reasons for pollution are weather conditions of winter, forest fires, the burning of stubble and waste and emission from vehicles and industries. Smoke and dust particles flowing through the air from a neighboring country are also major causes of air pollution in Nepal.
Low rain in winter means a high possibility of bad air quality because of the special weather phenomenon called ‘temperature inversion’. “There is a temperature inversion in winter so that dust particles or smog around the surface of the ground cannot go up to the top of the atmosphere, and air quality is reduced when it accumulates near the surface,” said a meteorologist at DHM.
In general, the higher you go in the atmosphere, the lower is the temperature. But with a temperature inversion, the higher the atmosphere, the higher be the temperature. Consequently, the surface formed in the atmosphere stops the dust particles and smoke from going up. The possibility of winter drought and weather indications are not in favor of good air quality right now and for the near future.
The main component of air pollution in Kathmandu and across the region is small dust particles, PM2.5. Dust particles that are 2.5 micrometers or smaller in the air are called PM 2.5. Such particles easily enter into the human body. According to the World Health Organization, PM 2.5 levels above five micrograms per cubic meter on average (annually) are considered harmful to health.
According to a recent report published by the World Bank, in South Asian countries including Nepal, the serious impact on public health along with the economic and social damage caused by air pollution.
According to the World Bank report, 9 out of 10 cities in the world have the worst air pollution in South Asia. Around two million people die every year due to air pollution in these polluted cities including Kathmandu.