What Is A Heatwave?
Heatwaves occur when excessively hot temperatures are often accompanied by high humidity, especially in oceanic climates. The term refers to both short-term variations in the weather and too rare, exceptional hot spells that may occur only once in a century.
During severe heat waves, crops fail, thousands of people die from hyperthermia, and power outages result from increased use of air conditioners. Heatwaves are considered extreme weather events that can be a natural disaster and a danger for the human body because heat and sunlight can overheat it. Forecasting instruments can be used to detect heat waves to issue a warning [3].
The India Meteorological Department (IMD) has set a number of criteria for declaring a heatwave for a region.
- Heatwaves are defined as conditions when the maximum temperature reaches 40 degrees Celsius or higher on the plains, 37 degrees Celsius or higher along the coast, and 30 degrees Celsius or higher in hilly regions.
- When the maximum temperature rises by between 4.5 degrees Celsius and 6.4 degrees Celsius above normal, it is also classified as a heatwave.
- A severe heatwave is declared when the maximum temperature deviates more than 6 degrees Celsius from normal.
- The third indicator of a heatwave is a maximum temperature over 45 degrees Celsius and up to 47 degrees Celsius on any given day.
How Do Heat Waves Affect Your Body?
A temperature above a certain point can affect bodily function and even prove fatal. The longer a person stays in elevated temperatures, the more serious the effects on their body are [4].
As the body heats up, blood vessels open up. This lowers blood pressure and makes the heart work harder to pump blood throughout the body, which in turn can cause mild symptoms such as an itchy heat rash or swollen feet as the blood vessels become leaky [5].
At the same time, sweating causes the loss of fluids and salts, affecting the balance between them in the body. Combined with lowered blood pressure, this can lead to heat exhaustion. Symptoms include the following [6]:
- dizziness
- headaches
- fainting
- nausea
- confusion
- muscle cramps
- heavy sweating
- tiredness
- If blood pressure drops too far, the risk of heart attacks rises.
Who Is More At Risk During A Heat Wave?
What To Do To Stay Safe During Heatwaves?
On A Final Note…
With the temperature only going up, climate experts are raising caution and advising people to stay indoors, especially during the afternoon hours. Stay hydrated, eat light and wear comfortable clothes.