There is an accelerated increase in the number of extreme thermal events on the planet. Previously, severe heat waves were limited to specific regions, but now they are spreading over vast areas of the world. If five major heat storms were recorded annually on average in the 1960s, the average number has risen to 102 in the current decade. This data was obtained by analyzing temperature indicators.
The most significant heat storm, which occurred between 2023 and 2024, lasted for 367 days and covered about 85 percent of the Earth's surface. The consequences of such long periods of high temperature are not limited to just an increase in average annual figures; they pose a threat to public health, contribute to drought, and increase the risk of wildfires. It was also found that various major events occurring simultaneously in different parts of the world may be related to the same heat storm.
A heat storm is defined as a very powerful heat wave that lasts for a long time and spreads over large areas of the planet. When the temperature in any region remains significantly above normal for five or more consecutive days, it is classified as a heat wave. However, the criteria for identifying heat waves vary in each country. For example, in the USA, a heat wave is usually referred to as abnormally hot days lasting two or more days, whereas some other countries have set a threshold of three days. Furthermore, there are differences in temperature thresholds, which makes direct comparison of such phenomena between different states difficult.
Within this study, a special standard was introduced for defining a heat storm: if a heat wave reaches at least one percent of the Earth's surface at its maximum level, it is classified as a heat storm. This approach allows for tracking thermal events affecting vast territories.
In the 1960s, the largest heat wave lasted 46 days and covered approximately 6 percent of the Earth's surface. Its impact was recorded in the Atlantic Ocean, some areas of Latin America, and West Africa. By the 1990s, such large-scale waves began to spread to other parts of the world, but vast areas of Asia and North America remained unaffected.
The current situation is drastically different. The largest heat storm of this decade lasted 367 days and affected about 85 percent of the Earth's surface, indicating that extreme weather events have begun to affect much wider regions compared to the past.
The heat storm that lasted during 2023–2024 affected many countries. In some areas of the Philippines, temperatures rose to 38 degrees Celsius. Since many schools there lacked air conditioning, students found it difficult to study in such intense heat, and the condition of some children worsened.
In Louisiana, USA, prolonged heat and drought led to an increase in wildfires. Around 600 fires were recorded there in August 2023. Later, due to smoldering fires in marshy areas, thick smog and fog formed, triggering a collision involving more than 158 vehicles on the road, resulting in seven deaths.
Meanwhile, near the city of Derna in Libya, two dams collapsed. The flooding caused by heavy rains led to widespread destruction. In Saudi Arabia, during Hajj, the temperature near the Grand Mosque in Mecca reached 51.8 degrees Celsius, leading to the death of over 1300 pilgrims.
The main reason for the rise in global temperature is climate change. In addition, seasonal phenomena such as El Niño also affect global temperature. During El Niño, water in some parts of the Pacific Ocean becomes warmer than normal, which affects the weather in many regions of the world and can lead to increased heat in certain places.
From the 1990s to the 2020s, there has been an expansion of the range of major thermal events. However, the growth in the number and scale of heat storms cannot be explained solely by the influence of El Niño; the increase in the Earth's average temperature and other climatic factors must be taken into account. Scientists point out that increased greenhouse gas emissions due to human activity prevent heat from escaping the Earth, leading to a rise in average temperature and an increased risk of prolonged severe heat. Events like El Niño can only temporarily exacerbate this heat.
Heat negatively affects human health, agriculture, water availability, and forests. Prolonged droughts increase the probability of wildfires. Monitoring heat storms helps to understand how extensive the area affected by heat is and what damage it causes to the population.