Why monsoon forecasts matter

The India Meteorological Department (IMD) has announced a normal southwest monsoon for this year. This will be followed by another update in June for the four-month season that ends in September. There will be monthly forecasts for July and August rainfall for the country as a whole, and also forecasts for rainfall over various geographical reasons. Each of these bulletins from the Met office is critical, given the fact that summer monsoon rains amount to almost 80 per cent of annual rainfall in India and is closely linked with irrigation, drinking water needs and hydropower production. For millions of people in India, these updates serve as early warnings about droughts and floods and are meant to help them plan farming operations. Every aspect of the summer monsoon — its onset, progress, quantum and distribution of rainfall and its withdrawal — is important.

The monsoon and other weather phenomenon are a dynamic process depending on multiple factors across the planet such as sea surface temperatures, El Nino and Southern Oscillation, Madden-Julian Oscillation, the extent of ice caps and so on. This makes the job of making long-range or seasonal forecasts risky. In fact, IMD is the only Met agency globally to release an operational seasonal rainfall forecast every year; others only have experimental ones. The agency has been constantly updating its forecasting capability in the past few years and has collaborated with meteorologists and researchers from America and elsewhere. As a result of the National Monsoon Mission launched five years ago, the Met department has significantly improved its forecasting skills. It now deploys a dynamical global ‘climate forecasting system’ model adopted from models used by the National Centers for Environmental Prediction (NCEP) of America. IMD has a grid of supercomputers that can crunch trillions of datapoints every second, and help in perfecting forecast models.  

All this means that the science part of monsoon forecasting has improved and is constantly adapting to new information and technologies, with adequate investments through initiatives like the National Monsoon Mission.

What about the society part? This is where we seem to be lacking. IMD is a scientific agency and passes on the forecasting information to the government, which in turn, makes it available to the state government for further dissemination through agriculture universities and extension systems. There are gaps in this system as well as the quality of forecasts. For any forecast to be of practical use, it has to be specific down to a region or even a district. During the monsoon season, there are dry spells and vast intra-seasonal variations. Total rainfall for the season may fall within the predicted limit but many areas may have got deficit rainfall, while others in plenty. So, clearly, one size does not fit all. We need more research and honing of skills in this area. The second point is about flow of information and sharing of data. IMD should open up its doors to private companies and groups who could make use of the Met data for wider use. The agency should incubate startups and perhaps encourage young scientists to become entrepreneurs. Like Antrix for the space sector, IMD should have a commercial arm. 

A bigger challenge is to prepare farming communities to face the vagaries of weather during the non-monsoon period. IMD’s own data shows that rainfall patterns across the country have changed, both during monsoon and non-monsoon periods. Temperature patterns are changing with factors like differences between day and night temperatures and maximum and minimum temperatures showing variation. Winter rains, so vital for crops in the hilly regions, have practically disappeared in the past few years. It does not rain when needed while at other times it is erratic or too heavy. Farmers are facing extreme weather events like hailstorms at several places. Heat waves too are becoming frequent. Now, we have summer predications also, and some states have initiated Heat Action Plans to reduce mortality and illness due to extreme heat. Overall, we need strategies and action plans to prepare communities for all weather-related changes, irrespective of the debate that such changes are directly linked with climate change or not. This would mean new cropping patterns, new climate resilient varieties and innovative water conservation plans. This calls for a year-round focus on weather forecasting and efforts to forge links with several agencies as well as communities directly.

The author is a New-Delhi based writer and columnist whose latest book The Outsourcer: The Story of India’s IT Revolution has been published by MIT Press.