When this storm develops in the Atlantic Ocean and northeastern Pacific Ocean it is called a hurricane, in the north-western Pacific Ocean is called a typhoon and in the south Pacific or the Indian Ocean is referred to as "tropical cyclones" or "severe cyclonic storms
Cyclone Amphan which started out as a Category I cyclone soon became a high-intensity cyclone. An IANS report says, studies say human activities may have influenced Amphan in several ways. Climate change is increasing the damage that cyclones cause in many ways, including increasing sea surface temperatures that raise the maximum potential energy that a storm can reach; increasing the rainfall that drops during the storm; rising sea levels, which increases the distance inland that storm surges reach; and causing storms to gain strength more quickly.
See Pictures: Cyclone Amphan Makes Landfall In India; Houses, Roads Shattered As Storm Wreaks Havoc
According to a study done by US-based National Oceanic and Atmospheric Administration (NOAA) and the University of Wisconsin-Madison Cooperative Institute for Meteorological Satellite Studies (CIMSS) after analyzing satellite imagery of tropical cyclones for over 40 years, it was found that the intensity of cyclones has increased. The study says that the ‘intensities are also consistent with expectations based on theoretical understanding and trends identified in numerical simulations in warming scenarios.’ They also found that during the years that were studied the intensity increased by 8 percent every decade.
Although researchers are still figuring out the connection and accurate results are impacted by regional variations, so far there are some indications that a warmer climate can increase the destructive capacity of tropical cyclones such as Amphan. Another study published in the journal Nature looked at data from 1982–2008 and found that computer simulations show that anthropogenic factors such as pollutants may have an impact on the intensity of tropical storms. According to the study, natural pollutants such as volcanic ash are not enough to explain the rise in Rapid Intensification or RI which is an estimation of the increases in the rate of cyclone intensification.
The Indian Ocean has a natural propensity to retain heat and along with the Arabian Sea and Bay of Bengal has pre and post-monsoon storm season which is aided by various meteorological conditions. Global warming is causing the temperature of the oceans to rise and there are more frequent occurrences of phenomena such as Indian Ocean dipole, a climatic condition that is caused by variation of sea temperatures. These events lead to unusually heavy rainfall, flooding, and drought in some places. These variations also impact the tropical cyclones, making them more destructive.
Also Watch: Amphan cyclone: Uprooted trees, streets swamped with water a common sight in Kolkata