Ice creams, cold coffees, long swims, short summer dresses; when you hear that, what does one associate these concepts with? Yes, you guessed it correct! Heat. Hot temperatures. While summer, with its warmer temperatures is a relief for many cold countries, it is quickly turning into a global climate emergency for many other countries across the world. Temperatures continue to rise beyond normal, in the form of heatwaves across the globe.
One can define a heat wave as a period of higher-than-average or record-breaking temperatures in a certain area. July 4th, 2023, was in fact, recorded as the hottest day ever on Earth. On Tuesday, Earth’s average temperature rose to 62.9 degrees. According to the Climate Reanalyzer of University of Maine’s, a tool based on satellite data and computer simulations, that’s the highest temperature recorded for that data set since the records began way back in 1979.
The unusual warmth is the result of a combination of human-caused climate change, the strengthening of the El Niño and the start of the summer in the Northern Hemisphere.
In June 2023, record breaking heatwaves were observed in Northern Mexico and South-central US, especially in Texas. All-time, record high temperatures have been tied in Texas cities such as Del Rio (115 degrees), Laredo (115 degrees) and San Angelo (114 degrees) last week. The heat index, which is ‘How hot it feels to the human body when humidity is factored in,’ reached an unofficial record of 125 degrees in Corpus Christi.
In the UK, the situation does not look any better. For the first time this year, temperatures have surged beyond 30°C, and meteorologists now predict a 45% chance—2.3 times the usual rate—that Britain will have a scorching summer. A repetition of last year’s record-breaking heatwave is predicted, which started wildfires, delayed rail travel, shuttered schools, resulted in hundreds of preventable deaths, and saw temperatures breach the – 40°C mark in the UK for the first time, is now conceivable.
Turning to India, it is battling with the same issue. India endured a scorching heat wave the previous year, with some areas of the nation reaching temperatures of more than 49°C (120°F). According to the Climate Reanalyzer, India had its hottest March and its hottest April ever, in 122 years in 2022. Additionally, researchers discovered that between January and October of 2022, India had 242 out of 273 days with intense weather.
So, the question arises- Why are temperatures rising across the world?
Heat waves occur when high atmospheric pressures move in and push warm air towards the ground. The atmospheric force then prevents the warm air from rising, resulting in the formation of a heat dome with trapped air beneath it. Without rising air, the pressure system compels weather to shift. This includes reducing wind and cloud cover and interfering with the cycle of formation of rain. The result is – hot, stuffy air that keeps getting hotter.
Another cause for these dominant heatwaves is the ‘El Niño effect’. El Niño causes a weakening or reversal of the Pacific tide winds, which reduces or even stops the upwelling of cold, nutrient-rich waters along the western coast of South America. The warm surface waters in the Central and Eastern Pacific Ocean consequently moves eastward towards the South American shores. This redistribution of ocean heat changes the patterns of air circulation, affecting the weather in various parts of the planet.
Climate change is without a doubt to blame for the world’s rising temperatures. Since the industrial revolution, there has been a significant increase in pressure on the atmosphere of our planet due to the exponential rise in ‘Greenhouse gas’ emissions, which are caused by burning of fossil fuels for energy and transportation, agriculture, as well as various industries. These emissions include carbon dioxide, methane, and nitrous oxide.
As more emissions are caused into the atmosphere, more gases are trapped, thickening the planet’s atmosphere, which in turn traps more solar heat, warming the earth’s surface. This is called as the ‘Greenhouse effect.’ The presence of heat waves is significantly influenced by the moisture in the atmosphere. Heat waves can have a significant impact on the population in high humidity circumstances, especially in cities with a larger people density, livestock, and wildlife. They tend to happen more frequently in dry, low-humidity settings. Scientists have been able to link the greater intensity and higher frequency of heat waves and comparable extreme climate events to human influence, even if it is impossible to quantify the precise impact of how climate change is creating heat waves.
Heat waves have broad repercussions that have an impact on many facets of society and environment. The danger they bring to human health is one of the concerns. Heat exhaustion, heatstroke, and even death can be the result of excessive heat. The elderly, even small children, and people with underlying medical issues are at risk. The death rate might increase during heat waves. Healthcare systems and infrastructures need to be developed to avoid these deaths. Heatwaves have impact on the agriculture as well. Food insecurity is made worse by heat stress on agricultural crops and livestock, which reduces yields and costs farmers money.
Heat waves also exacerbate dry conditions and aid in the escalation of wildfires. Dry and hot conditions enhance the chances of forest fires, wreaking havoc on ecosystems and endangering wildlife species. Forest fires in turn contribute to air pollution. Toxic gases which are hazardous to health are emitted into the atmosphere. They have disastrous effects on animals, humans, plant life, as well.
Even the economic impact of heatwaves is disastrous. The economic effects of heatwaves encompass reduced agricultural productivity, increased energy demand, infrastructure damages, impacts on tourism and recreation, decreased labor productivity, higher healthcare costs, insurance claims, supply chain disruptions, and market instability. These economic consequences highlight the urgent need to address climate change and develop adaptive strategies to mitigate the risks posed by heatwaves.
Heat waves are a glaring example of the developing climate problem, which is mostly brought on by human activity and made worse by climatic norms. Heat waves have wide-ranging effects on economies, ecosystems, and human health. Reducing greenhouse gas emissions and switching to renewable energy sources is needed to mitigate climate change. In order, to increase resilience and safeguard vulnerable communities from the negative consequences of heat waves, adaption mechanisms must also be put into place. We can endeavor to reduce the intensity and frequency of heat waves around the world by addressing the underlying causes and putting in place all-encompassing remedies, eventually protecting the health of both the present and future generations.
Written by – Tanisha Lakhani
Edited by – Mrunmayee Patwardhan