A United Nations assessment has found that 2024 is projected to be the hottest year on record. The unprecedented heat caused by human activities has persisted for a decade, resulting in extreme weather events that have had a more severe impact on societies and economies around the globe than ever before. Experts anticipate that the global average temperature is likely to continue rising in 2025.
The World Meteorological Organization (WMO) stated on the 30th that "the impact of climate change in 2024 has hit the world, affecting extensive areas, from mountains to the depths of oceans worldwide," adding that "greenhouse gas levels are continuously increasing to record highs, and even more heat is expected to come in the future."
António Guterres, Secretary-General of the United Nations, issued a statement on this day before the new year, saying, "The recent decade, including 2024, has been the hottest decade in human history," and noted, "Climate collapse is happening in real-time, and we must urgently get off the path of destruction." Celeste Saulo, Secretary-General of the WMO, also said, "The frequency and intensity of extreme weather events caused by climate change are now occurring daily," and added, "Storms and floods that have occurred in various places have caused numerous fatalities and brought great sorrow to communities across all continents."
The WMO will officially announce a comprehensive report on global temperature data for 2024 in January. Additionally, a report detailing the global climate status is expected to be released in March.
◇ First time exceeding the 1.5 degree threshold compared to transfer
In November, the WMO revealed that the global average temperature from January to September 2024 was 1.54 degrees higher than the average from 1850 to 1900, prior to the Industrial Revolution, and exceeded last year's record increase of 1.45 degrees. This is the first time that the global average temperature has surpassed 1.5 degrees compared to pre-industrial levels. The Paris Agreement, signed in 2015, aims to limit the rise in the Earth's temperature to below 2 degrees compared to pre-industrial levels, and if possible, to 1.5 degrees. According to the climate change scenarios (RCP) announced by the Intergovernmental Panel on Climate Change (IPCC), an average temperature increase of 2 degrees compared to pre-industrial levels will lead to extreme rainfall events occurring annually, devastating communities and infrastructure.
Climate change has now escalated to the point where the term "climate collapse" has been introduced. This term, proposed by the British newspaper The Guardian, encompasses a much broader concept than global warming, signifying the complete breakdown of the climate that humanity has relied on for growth and survival.
According to a report released on the 27th by the multinational research groups World Weather Attribution (WWA) and Climate Central, the world experienced an additional 41 days of 'dangerous heat' in 2024, which would not have occurred without climate change. A volunteer research team composed of scientists from various countries compared the daily temperatures worldwide in 2024 to the temperatures expected without the climate crisis. The result showed that 'dangerous heat,' defined as the top 10 percent of temperatures from 1991 to 2020, significantly increased last year, exposing millions to health-threatening environments.
In some regions, it was confirmed that extreme heat persisted for more than 150 days. Additionally, of the 29 extreme weather events that occurred last year, 26 were found to have been influenced by global warming. As a result, 3,700 people died, and millions lost their homes.
◇ Routine climate disasters... is climate collapse coming?
Routine climate disasters, including hurricanes, floods, wildfires, and droughts, have become the 'new normal.' While the number of tropical storms, such as typhoons and hurricanes, has decreased, they are gaining strength by receiving more energy from warm ocean waters.
In September, Storm Boris swept through central and eastern Europe, causing dozens of fatalities and severe damage from flooding to buildings and infrastructure. Scientists revealed that the flooding during that time was the result of human-induced climate change, which doubled the rainfall. In the same month, Hurricane Helen struck six U.S. states, resulting in 230 deaths. U.S. weather authorities classified Helen as the deadliest storm to hit the continental United States in decades. Just weeks later, Hurricane Milton struck the southeastern U.S., which was also analyzed to have strengthened due to ocean warming. Experts estimate that global warming is increasing the likelihood of severe hurricanes like Helene and Milton by 200 to 500 times, while also predicting an increase in rainfall by about 10%.
The situation is also severe in the Indian and Pacific Oceans. Last year, six typhoons struck the Philippines within 30 days, affecting 13 million people. From October 10 to 15, Cyclone Chido hit the French territory of Mayotte in East Africa, resulting in more than 1,000 fatalities. Severe floods and landslides have also followed in Africa and South America. In Africa, floods in Sudan, Nigeria, Cameroon, Niger, and Chad have resulted in at least 2,000 deaths and millions of displaced persons.
While one region is experiencing flooding, another is enduring the effects of heatwaves and drought. In some countries in Asia, Europe, and Africa, temperatures exceeded 50 degrees last year on several occasions. Indonesia experienced dangerous heat for 122 days, and Singapore and various countries in Central America also faced heatwaves. In the Middle East, Saudi Arabia saw hot weather continue for 70 days, leading to 1,301 heat-related deaths among pilgrims during the Hajj in June. On the hottest day recorded, July 22, 5 billion people, or two-thirds of the global population, felt the heat.
In some areas, severe drought has led to wildfires, resulting in additional damage. The Amazon, often referred to as the 'lungs of the Earth,' is nearing a point of no return, having experienced the most severe drought on record last year. As the forest becomes increasingly dry, NAMUGA trees are dying en masse, resulting in a significant amount of carbon dioxide being released into the atmosphere.
South Korea also experienced extreme weather anomalies during the same period. The Korea Meteorological Administration reported that last summer's average temperature and number of tropical nights were the highest in the history of weather observations, with about 80% of the total summer rainfall concentrated during the monsoon period. Instances of intense rainfall often manifested in very localized areas during the rainy season. It was a peculiar year marked by severe flood damage alongside many areas experiencing drought.
Frederik Otto, a professor at Imperial College London and a co-founder of WWA, stated, "There has never been a year as clear and destructive in the impact of warming as 2024," and emphasized that to prevent further deterioration, the use of fossil fuels must be urgently halted.
◇ Heat is expected to continue into 2025
Some argue that the temperature rise observed in 2023 and 2024 is due to the influence of El Niño. El Niño is a phenomenon characterized by sea surface temperatures in the eastern Pacific remaining higher than usual in cycles of 2 to 5 years, impacting global climate. It is viewed that the El Niño phenomenon temporarily raised global temperatures and contributed to the increase in greenhouse gas emissions.
However, many experts believe that the impacts of the climate crisis extend beyond the effects of natural weather patterns like El Niño. While it is true that El Niño contributed to some extreme weather events in 2024, analyses show that climate disasters like the drought in the Amazon and severe flooding in Africa are a result of the climate crisis.
Experts predict that while the impact of El Niño will diminish, with the development of La Niña causing Pacific sea temperatures to drop in 2025, temperature rises are expected to continue following the trends of 2023 and 2024. The WMO has warned that record heat is likely to persist in 2025. The UK Met Office projects that the average global temperature in 2025 will also be 1.29 to 1.53 degrees higher than pre-industrial levels.
◇ A monitoring system for heat-related deaths needs to be established
The global average temperature has exceeded 1 degree above pre-industrial levels for 12 consecutive years. The United Nations Environment Programme (UNEP) report released last year warned that if greenhouse gas emissions, the cause of temperature rises, are not reduced, the average temperature could rise by an additional 3.1 degrees by the end of this century. Experts believe that greenhouse gas emissions are currently breaking records and that temperatures are expected to continue to rise. The WMO stated, "As greenhouse gas levels continue to set new records, there is a likelihood of more heat in the future," emphasizing that increased international cooperation is needed to address the problems of rising global temperatures and more frequent extreme weather phenomena.
Scientists unanimously agree that a global monitoring network for assessing deaths due to extreme heat needs to be strengthened. It is estimated that countless people have died from global warming over the past few decades, but precise assessments are still lacking. Experts believe that the absence of monitoring systems has led to a serious underestimation of deaths caused by heatwaves.
An expert group composed of 15 international organizations, 12 national governments, and various academic and non-governmental organizations (NGOs) convened on December 4 in Geneva, Switzerland, at the WMO headquarters to discuss measures to address the increasing climate threats. The WMO is implementing the "Early Warnings for All" initiative, which aims to improve climate services and early warnings to enhance public health.
The WMO believes that 2025, marking its 75th anniversary, is an opportune time to strengthen international efforts to mitigate climate change. The WMO and UNESCO have declared 2025 as the "International Year for Glacial Preservation," intending to raise global awareness regarding the rapidly changing ice and permafrost due to warming.
Reference materials
WWA (2024), https://www.worldweatherattribution.org/when-risks-become-reality-extreme-weather-in-2024/