“In summer, the pressure of the sea air becomes higher than that of the land, that heated air moves towards the land, that process is called the arrival of monsoon.”
KATHMANDU:- There are only four days left for this year’s monsoon to arrive. The monsoon arrival date has been shifted a few days earlier than last year, to June 13. Accordingly, the Department of Hydrology and Meteorology has stated that the environment for the monsoon arrival may be created within the next week.
According to the department, the monsoon low pressure area has entered Kerala, India, on June 4. It will take about 10 days to reach the eastern part of Nepal from there. Meteorologist Rojan Lamichhane said, “The monsoon that has advanced from the Bay of Bengal is in the process of advancing from Kerala and may enter from the eastern part of Nepal.” He said that there is a possibility of the monsoon spreading to a small area in the east initially.
A team of meteorologists is currently studying the arrival of the monsoon in Nepal without missing a single minute. Meteorologist Lamichhane said, “We have been continuously holding collective and international discussions for the past few days. Our focus is on how it will arrive and how effective it will be.”
Every year, the rainy season follows the spring season. During this change of seasons, air pressure increases on both the land and sea surfaces. According to meteorologist Sanjeev Adhikari, during the summer, air with water particles flows from the sea to the land, while during the winter, warm air from the land moves towards the sea. This overall process is called monsoon. The arrival of monsoon means the movement of water vapor-rich air with water particles towards the land. He said, “In summer, the pressure of the sea air becomes higher than that of the land, that heated air moves towards the land, that process is called the arrival of monsoon.”
80 percent of the annual rainfall in Nepal falls during the monsoon season. The monsoon winds that come to Nepal are initially created around Madagascar, a South African country in the southern hemisphere of the earth. With the environmental changes there, the pressure of the monsoon winds also increases in the Bay of Bengal. From there, that water vapor becomes monsoon winds and enters the eastern region of Nepal via Kerala and Madhya Pradesh in India.
The monsoon, which enters in the fourth week of Jestha (May), usually leaves in the third week of Asoj, (August). According to meteorologist Adhikari, another system that causes rain during Nepal’s monsoon develops in the Arabian Sea. The water vapor-laden air there causes monsoon rain in the central and western regions of Nepal. The average location of the monsoon low-pressure line entering Nepal is around the Ganges coast of India. From there, when that line moves closer to the southern Terai of Nepal along with the water vapor-laden air, Nepal experiences more rainfall.
Agricultural meteorologist Rameshwor Rimal said that the arrival of the monsoon is not certain. He said, “It seems that the monsoon will be delayed in Nepal, while farmers have already planted the beds, and we are not able to say how to do farming.” Even after the monsoon arrives, if there is no rain when the next water is needed, the rice will burn or drown in heavy rain. We have initially said to plant rice that is drought and flood-tolerant. He said that suggestions to the government and an overall agricultural forecast can be decided after the monsoon arrives.
