History of forecasting: From thermometer to supercomputer

Written by Sandip Das | Updated: May 5 2013, 05:31am hrs
While tracing the origin of forecasting rains, it could be concluded that the beginnings of meteorology or predicting rains in India could be traced to ancient times. Early philosophical writings of 3000 BC era, such as the Upanishads, contain references about the processes of cloud formation, rain and the seasonal cycles caused by the movement of earth around the sun. Varahamihiras classical work, the Brihatsamhita, written around 500 AD, provides clear evidence that a deep knowledge of atmospheric processes existed even in those times. It was believed that rain came from the sun and that good rainfall in the rainy season was key to bountiful agriculture and food for the people.

Kautilyas Arthashastra contains records of scientific measurements of rainfall and its application to the countrys revenue and relief work. Kalidasa in his epic Meghdoot mentioned the date of the onset of monsoon over central India and traced the path of monsoon clouds.

However, IMD officials say modern meteorology had its firm scientific foundation in the 17th century after the invention of the thermometer and barometer, and the formulation of laws governing the behaviour of atmospheric gases.

Wind directions, observatories

Research by the weather department had stated that in 1636, Halley, a British scientist, published his treatise on the Indian summer monsoon, which he attributed to a seasonal reversal of winds due to differential heating of the Asian land mass and Indian Ocean.

Incidentally, some of the oldest meteorological observatories of the world are located in India. The East India Company established several such stations, such as the one in Kolkata in 1785 and Chennai in 1796, for studying Indias weather and climate. The Asiatic Society of Bengal, founded in 1784 at Kolkata and in 1804 at Mumbai, promoted scientific studies in meteorology in India.

Beginning of IMD

A disastrous tropical cyclone struck Kolkata in 1864 and this was followed by monsoon failures in 1866 and 1871. In 1875, the government established the India Meteorological Department (IMD), bringing all meteorological work in the country under a central authority. The headquarters of the IMD were later shifted to Shimla from Kolkata then to Pune, and finally to New Delhi.

From a modest beginning in 1875, the met department has expanded its infrastructure for meteorological observations, communications, forecasting and weather services and has achieved parallel scientific growth.

Computers, satellites

One of the first few electronic computers introduced in the country in 1980s by then prime minister Rajiv Gandhi was provided to the IMD for scientific applications in meteorology. India was the first developing country in the world to have its own geostationary satellite, INSAT, for continuous weather monitoring of this part of the globe and particularly for cyclone warning.

The IMD has always used contemporary technology. In the telegraph age, it made extensive use of weather telegrams for collecting observational data and sending warnings. Later, the IMD became the first organisation in India to have a message switching computer for supporting its global data exchange, says Shailesh Nayak, secretary, ministry of earth sciences.

Supercomputers

The IMD, at present, has a High Power Computing System (HPCS) with a capacity of around 120 Tera Flops located at several institutes across the country. And following the governments recent move to hike computing capability further, things can only improve.

The national Monsoon Mission, launched last year with a budgetary support of R400 crore for five years to support research work related to the mission, will help implement a dynamic prediction system for the prediction of monsoon in all time scales, short range to seasonal, at appropriate spatial scales with improved prediction skill.