Altering Monsoon Pattern

When it was already time for the monsoon to retire, it was raining cats and dogs in western hills of the country this year. The cloudbursts triggered disasters in the form of landslides, flashfloods and inundation causing loss of lives and properties. A decade ago, the monsoon's duration was limited to 106 days but now it has been extended to 120 days. Monsoon is supposed to end by the first week of October but it is getting delayed in recent years. In Nepal, about 80 per cent of the annual rainfall takes place in June, July, August and September. The moisture laden wind coming from the Bay of Bengal is showing unusual and unpredictable dynamism in recent decades. Heavy rains are falling in calamitous proportions in some Himalayan regions like Manang while some Terai areas experienced prolonged droughts and farmers there could not carry out timely paddy plantations there. This phenomenon has been attributed to rising global temperatures that cause climate change. 

Climate change is now a pressing global issue. Scientists say that Earth’s average temperature has been rising at an alarming rate since the mid-20th century. The increasing global warming is impacting the climate negatively. The greenhouse emissions, caused by the burning of fossil fuels such as coal, oil and natural gases, has increased the temperature, resulting in the rise of sea level, snow-melting, storms, unpredictable rainfall, floods and landslides. The world has witnessed unusual pattern of rain, which has been attributed to the rising temperature that intensifies the Earth’s water cycle.  A warmer climate triggers evaporation of water from land and sea, and warmer atmosphere holds more moisture, causing extreme rainfall. With the increase in evaporation, there are instances of extreme rains but the distribution of rainfalls is not even and balanced.  There are rising cases of extreme rains as well as dry spells and droughts, all this inviting adverse consequences on various sectors of life. 

Scientists say that the degree of warming and precipitation are increasing over the years and decades. But the meteorologists are finding it difficult to identify the altering weather patterns and make accurate predictions. Thus, things like the farmers' working calendar to weather forecasting technologies have to make shifts accordingly. The change in the pattern of rainfall is considered a noticeable element that highlights the impact of climate change which has roiled the entire humanity.  Nepal has also experienced vagary of monsoon as well as rainfall, impelling meteorologists to scratch their head to make a precise prediction on the rainfall and other events in the atmosphere. Considering the changes in the monsoon air character, the Department of Hydrology and Meteorology revised the monsoon onset and withdrawal time three years ago. Now the duration of monsoon is considered to be 112 days, from June 13 to October 2.  The Department updates the entry and exit dates of the monsoon every decade based on its trend of three decades. 

However, the revised date of monsoon period does not still seem accurate. Like last year, monsoon stretches up to mid-October this year. It has not yet formally withdrawn from Nepal, according to a news report of this daily. The prolonged monsoon dampened the festive mood of Dashain festival recently. The people celebrated it amidst the heavy downpour, terming it hile (muddy) Dashain. Not only this, heavy rain lashed different parts of country during and after Dashain, killing many people and destroying the property worth millions of rupees, particularly in Karnali Province. In the Terai belt, paddy crops planted in a large swath of land were damaged.