In 1950s and 1960s, Indian budget was regarded as a gamble on the monsoon rains. This holds good even now. Understanding and forecasting monsoons are crucial for Indian agriculture, as they account for nearly 70 per cent of the annual rainfall in the country. Monsoon forecast is the most talked about but least understood topic in India. It has such far reaching implications and political overtones that even India Meteorological Department (IMD) treads very carefully in the area of monsoon forecasting.
From the early days of 16 parameter model to latest ensemble technique, monsoon forecasting is in ever evolving mode, mainly because monsoon is a complex phenomenon. And it is believed that a complete understanding of monsoon forecasting is well-neigh impossible.
Thus, in quest for further improvement, IMD is now embarking on Rs.350 crore project to see how Himalaya’s presence affects monsoon circulation over the Indian sub-continent. In the first phase, the IMD will be setting up three Doppler Weather Radars with weather, snow and other gauges, in Jammu and Kashmir, Himachal Pradesh and Uttarakhand at a cost of Rs. 108 crore. This will be followed by similar stations across the Northeastern States at a cost of Rs. 250 crore to study temperature, wind speeds and other meteorological parameters.
Understanding the role of Himalayas in the context of Indian climate in general and monsoon in particular is crucial. In the past, the role of Himalayan snow cover has been studied in the 16 parameter model. A recent study has shown that pollution from China, India and Nepal can reach altitudes of over 5,000 metres in the Himalayas. This will contribute to the warming of the atmosphere and potentially affecting the Indian monsoon cycle. The French-Italian team, whose findings were published in Proceedings of the National Academy of Sciences in 2008, studied all this over a 16-month period at the Himalayan Nepal Climate Observatory site in Khumbu Valley, at nearly 5000 metres.
The study team pointed out that when pollutants such as vehicle fumes transported from the plains of Nepal and other Himalayan countries, meet down-sloping cleaner air from the troposphere. In this portion of the Earth's atmosphere aerosol particles are formed. Discussing the implications of the study, aerosol particles emitted by burning processes absorb sunlight, causing warming of the lower atmosphere and thus, contributing to global temperature rise to the same extent as major greenhouse gases. This atmospheric warming can have a significant effect on the Southwest monsoon, as the functioning of monsoon cycle depends upon temperature regulation, the production of warmth in the atmosphere and rise or fall of atmospheric temperatures.
Thus, these are just the few areas on which, these radar stations will provide some more information but only time will tell how many other monsoon mysteries may be unlocked which are lying imprisoned in the deep ravines of Himalayas.