Weather Phenomena are defined as observable, dynamic events or conditions that occur in the Earth's atmosphere over short periods, ranging from minutes to days. These atmospheric events, which include temperature fluctuations, precipitation (rain, snow), wind, and atmospheric pressure changes, are a fundamental scientific concept.
The formal, modern study of these phenomena in India led to the creation of the India Meteorological Department (IMD), an institution established on January 15, 1875, by the Government of India. The IMD was founded in response to devastating weather events, such as the 1864 tropical cyclone in Calcutta and subsequent monsoon failures, which highlighted the need for a central authority to monitor the atmosphere.
The mechanism behind weather phenomena is driven by differences in air pressure, temperature, and moisture, primarily occurring in the troposphere. Differential heating of the Earth's surface by the Sun creates temperature contrasts, which in turn cause pressure differences. This pressure gradient moves air, creating wind and leading to the development of complex weather systems like cyclones and the Indian Monsoon.
The IMD, which operates under the Ministry of Earth Sciences (MoES), is connected globally as one of the six Regional Specialised Meteorological Centres (RSMC) of the World Meteorological Organisation (WMO). The IMD's forecasting mechanism has changed recently with the adoption of the Bharat Forecasting System (Bharat FS), which uses a higher-resolution 6-km grid model, improving upon the older 12-km model. Furthermore, the IMD is increasingly integrating Artificial Intelligence (AI) and Machine Learning (ML) models, alongside supercomputing upgrades like 'Arka' and 'Arunika', to enhance the speed and accuracy of severe weather predictions.