Extreme weather events such as thunderstorms, heavy rains, heatwave, cold wave, cyclone, floods, and drought have a significant impact on the environment. A cold wave is a prolonged period of freezing weather in which a sudden invasion of frigid air over a vast area takes place. Cold waves are most common in India during the winter months, i.e., November to February - and can last up to three weeks.
This is a localized seasonal phenomenon that is widespread in all states except southern Indian states. The north, especially the plains adjacent to the hills of India, make up the core cold wave zone that spans 17 states / UT. From November to February, minimum temperatures fall below 8 ° C in many parts of northern India. January and December are the coldest months, with a minimum temperature below 6 ° C in most of the northwest and below 8 ° C in other parts of North India.
In general, scientists and policymakers worldwide are discussing in the context anthropogenic global warming, which can lead to the occurrence of cold spells reduction worldwide. Cold periods occur when the recorded global average temperature (SAT) is warmest and coldest for a period of time. The most recent cold spells in East Asia and the United States have led to discussions of what could be in store for us in the future. Cold waves in East Asia are associated with the atmospheric circulation regime, which primarily revealed substantial Ural blocking height(UBH) anomalies and recorded Siberian surface height (SSH) anomalies.
The frequencies of cold waves in different country states for various periods are shown on the Indian map with an average number of a wave throughout the year.
Historically, cold times were considered "cold weather" and were treated as seasonal changes in India. Due to the occurrence of cold spells limited to specific country regions, cold spells tended to fall under national responsibility and were treated as regional disasters requiring minimal disaster preparedness or mitigation measures. The cold waves have had a significant impact on health. There was severe damage to crops, horticulture, forest trees, livestock, fisheries, and water. Utilities, power supply, transportation, tourism, social activities, the economy, and other livelihood systems have caused economic losses to the agricultural community. The cold wave has also affected various service sectors, including vegetable sellers, rickshaw pullers, day laborers, and street kiosk operators.
The effects of cold spells on people can lead to death and injury. Mortality rates have shown a significant increase in areas where cold spells recur. Health problems are more often observed in the elderly & in Newborn babies. In India, the cold waves from 2001 to 2019 had killed 5091 people in various states.