In stark contrast to initial forecasts, the monsoon has not been disrupted and rainfall continues across much of the country. (Representative image: PTI)
The meteorological department predicts that rainfall this month will be 94% to 106% of the long-term average (LPA), which is within the normal range. However, the final closing price was nearly 15% higher than normal
August is coming to an end after catastrophic floods in Gujarat and a “rare” cyclone in the Arabian Sea, with “above normal” rainfall across the country, well above the “normal” initially forecast by the India Meteorological Department (IMD) for the third monsoon season months of rainfall.
The meteorological department predicts that monthly rainfall will be 94% to 106% of the long-term average rainfall (LPA), which is within the normal range. However, rainfall ended up being 15% above normal, with excessive rainfall occurring in parts of Gujarat, Rajasthan, Tamil Nadu and Madhya Pradesh, causing catastrophic flooding in some areas.
“We had originally forecast rainfall to reach 106% of the LPA, but the actual situation was almost 15% away from that limit. Rainfall did exceed expectations. This is mainly due to the continuous low pressure system that continues to bring more rainfall this month,” Director General of Meteorology (DGM) M Mohapatra said on Saturday.
Low pressure systems are cyclonic disturbances that are a regular feature of the southwest monsoon and are responsible for most of the rainfall. The IMD chief said the formation of such systems varies between seasons and is not well predicted in global climate prediction models.
“One problem when making seasonal forecasts for a month or a season is that global climate forecast systems have limitations in capturing intraseasonal changes, such as the formation of low-pressure systems. They can do a good job of predicting large-scale storms that bring abundant rainfall. system. But it is currently impossible to predict the number of depressions/low pressures that will form in a month.
“One problem when making seasonal forecasts for a month or a season is that global climate forecast systems have limitations in capturing seasonal changes such as the formation of low-pressure systems. They can do a good job of predicting large-scale events that can bring abundant rainfall. systems. But it is currently impossible to predict the number of such systems (low pressure/low pressure) that will form in a month.
Cyclone Asner
As many as 6 low pressure systems formed in August lasting 19-20 days as against the normal 16.3 days, two of which intensified into low pressure/deep low pressure (advanced stage). One of the systems was so intense that it moved from Madhya Pradesh to Gujarat within a few days and entered the Arabian Sea as Cyclone Asnar on August 30 – a “rare” phenomenon, Because most cyclones form before or after the southwest monsoon season. In the past 100 years, only three cyclones have formed in the Arabian Sea in August.
“If we could predict the number of such systems forming each month or each season, then we could certainly address this gap. But currently this is not possible on a global scale and we are working hard to achieve this goal.
The meteorological department's forecast for July rainfall (normal range 94-106%) was also on the high side, with actual rainfall 9% higher than normal.
The monsoon has not broken so far
In sharp contrast to initial forecasts, the monsoon has not been disrupted and rainfall continues across much of the country. IMD expects the suspension to take place around August 8-10. However, the monsoon trough becomes active during this period and remains north of its normal position, bringing ample rainfall to northwest and central India. Around August 23rd to 31st, it quickly moved southward, bringing heavy rain to the western region.
This month also set a climate record for the highest and lowest temperatures (monthly average) in India in the past 100 years. The monthly average minimum temperature is 24.2℃, and the same period of the year is 23.6℃, which is nearly 0.61℃ higher than the same period of the year. This is part of the country's long-term warming trend as global temperatures rise.
