New Delhi: Scorching temperatures and heatwaves are battering Delhi with people desperately hoping for an end to the twin problem. According to reports, while the temperature in the national capital was 41 degrees Celcius on May 23, the ‘heat index’ was 50 degrees Celcius. On May 22, the index went even higher to 55.4 degrees Celcius. As Delhi grapples with the problem of soaring heat, let us take a look at what is heat index.
What is the heat index?
Also known as ‘real feel’, the heat index is a metric which takes into account both the heat and humidity in the weather. It has another term, ‘apparent temperature’, and to put it in simple terms, the heat index is the temperature that we feel when relative humidity is combined with the air temperature. It is an important measurement as it helps us to determine if the weather is comfortable or not for the human body.
When our body becomes too hot, it begins to perspire to bring down the temperature. However, the body cannot control its temperature if the perspiration is unable to evaporate as it is an essential cooling process. When the moisture content or the relative humidity in the atmosphere is high, the evaporation process from the body slows down, which simply means that we feel warmer in humid conditions which increases the chances and risks of heat stress.
On the other hand, when the relative humidity decreases, the rate of perspiration goes up. While the body feels cooler in arid conditions, the air temperature, relative humidity and the heat index are related. It means that as the air temperature and relative humidity increase, the heat index increases. It is important to note that every individual perceives heat differently due to several physical conditions. The heat index is based on reports of how hot subjects feel at a given temperature and humidity. Apart from the heat index, there are other measures of apparent temperature like the Canadian humidex and the relative outdoor temperature.
In July 2023, the India Meteorological Department (IMD) launched the heat index as an experiment to provide general guidance for the regions within India where the apparent temperature was on the higher side causing discomfort for the people which could guide people about the need to take additional care during summer. From April 1, 2024, the IMD started calculating the heat index as a more accurate indicator to gauge the discomfort level of people.
Also known as ‘real feel’, the heat index is a metric which takes into account both the heat and humidity in the weather. From April 1, 2024, the IMD started calculating the heat index. knowledge Knowledge News, Photos and Videos on General Knowledge
