The United Nations World Meteorological Organization (WMO) says last month was the warmest April on record - the eleventh month in a row with record global temperatures. Sea surface temperatures have also been at record highs for the past 13 months. While recent extreme weather events have caused numerous casualties and socio-economic disruption, the WMO warns that climate change is making heat waves - one of the deadliest types of weather - more extreme.
In recent weeks alone, more than 1 million people have been affected by floods, including in Afghanistan, Brazil, Kenya and Pakistan. Around the world, hundreds of people have lost their lives as a result of severe weather events. Southern Africa is facing the prospect of failed harvests due to drought, and Southeast Asia is grappling with a widespread heat wave.
According to monthly reports from the European Union-funded Copernicus Climate Change Service (C3S) and the United States National Oceanic and Atmospheric Administration (NOAA), the extraordinary period of record temperatures has been fueled by the naturally occurring El Niño weather phenomenon and the additional energy trapped in the atmosphere and ocean by greenhouse gases from human activities.
El Niño occurs on average every two to seven years, and episodes typically span 9 to 12 months. It is a naturally occurring climate pattern associated with warming ocean surface temperatures in the central and eastern tropical Pacific. However, the pattern occurs in the context of a climate that has been altered by human activities.
April 2024 had an average surface air temperature of 15.03°C, 0.67°C above the 1991-2020 average for April and 0.14°C above the previous high set in April 2016, according to CCRS. Last month was 1.58°C warmer than an estimate of the April average for 1850-1900, the designated pre-industrial reference period.
A similar streak occurred previously during the strong El Niño of 2015-2016, according to the WMO. Monthly breaches of 1.5°C do not mean the world has failed to meet the temperature goal of the Paris Agreement, which refers to a long-term temperature rise over decades.
Under the Paris Agreement, countries agreed to make deep cuts in global greenhouse gas emissions to keep the long-term global average surface temperature increase well below 2°C above pre-industrial levels and to pursue efforts to limit it to 1.5°C.
Global temperature changes are typically measured against the average temperature over a historical, pre-industrial baseline of 1850-1900. This baseline is the earliest period for which high-quality observations of land and ocean surface temperatures are available.
The first months with an average temperature greater than 1.5°C above the pre-industrial average occurred during 2015-2016, driven by both human-caused climate change and a strong, naturally occurring El Niño.
The latest record temperatures in 2024 were accompanied by extreme weather events - including drought in Southern Africa, devastating rains and floods in East Africa, Brazil and Afghanistan, and intense heat in many parts of Asia. According to a new study by the World Weather Attribution Project, climate change made the deadly heat waves that affected millions of vulnerable people more extreme.
The study confirmed that the role of climate change is likely to be similar in magnitude to the heat waves in South Asia studied in 2022 and 2023, which were found to be about 30 times more likely and much hotter. In the Philippines, the event would have been impossible without human-induced climate change. In West Asia, climate change increased the likelihood of the event by about a factor of 5.
Drought hit Southern Africa, particularly Malawi, Zambia, and Zimbabwe, and extreme rainfall struck the Arabian Peninsula. Persistent torrential rains in East Africa and southern Brazil worsened during the first week of May, causing devastating and deadly flooding.
Afghanistan also suffered deadly flash floods in mid-May, killing more than 300 people and causing widespread destruction of homes and infrastructure. Since the start of the March-May rainy season, Kenya has experienced heavy rains that have led to widespread flooding and landslides in several regions, resulting in more than 260 deaths and affecting hundreds of thousands of people.
“The high number of extreme weather and climate events (including record daily and monthly temperatures and rainfall amounts) are more likely in a warmer world,” said WMO climate expert Alvaro Silva in a statement.
“The sea surface temperature in several ocean basins, including in the tropical belt, continues to be record high, releasing more heat and moisture to the atmosphere and thus exacerbating conditions,” he said.
According to C3S, the average global sea surface temperature for April 2024 was 21.04°C, the highest on record for that month, just below the 21.07°C recorded for March 2024.
Throughout April and extending into May 2024, extreme record-breaking heat led to severe impacts across the Asian continent.
Much of Asia - including Israel, Lebanon, Syria, Bangladesh, Thailand, Vietnam, and the Philippines - experienced temperatures well above 40°C for many days. The heat was particularly difficult for people living in refugee camps, camps for internally displaced persons (IDPs) and informal settlements, as well as for outdoor workers.
Heatwaves are among the deadliest types of extreme weather events, and while the death toll is often underreported, hundreds of deaths have already been reported in most of the affected countries, including Palestine, Bangladesh, India, Thailand, Myanmar, Cambodia and the Philippines. The heat has also had a major impact on agriculture, damaging crops and reducing yields.
While most media attention focuses on daily maximum temperatures, it is nighttime temperatures that pose the greatest health risks, especially for vulnerable populations. Elevated daily minimum temperatures are particularly dangerous to human health because the body cannot recover from hot days.
India experienced repeated heat waves in April and early May. In Bangladesh, schools were closed as a precaution against the dangerous heat. Thailand set many new temperature records. Myanmar also set new temperature records, while Mexico experienced unusually high temperatures.
According to the Intergovernmental Panel on Climate Change (IPCC), limiting global warming to 1.5 degrees Celsius instead of 2 degrees Celsius over the long term could result in about 420 million fewer people being exposed to extreme heat waves.
Experts predict that the effects of climate change will intensify in the coming years, leading to more extreme weather events that will exacerbate ongoing crises, especially in protracted complex emergencies related to armed conflict, hunger, poverty and economic crises. It is the world's most vulnerable people who are most at risk from the climate crisis, even though they have done the least to cause it.
But the climate crisis is not only exacerbating existing humanitarian emergencies. It is closely linked to an increase in humanitarian crises affecting many millions of people around the world and posing immense challenges to the world. Devastating storms, floods, historic droughts and extreme heat waves are killing people, destroying livelihoods, causing hunger crises and spreading disease.
One of the most tragic consequences of the climate emergency is the forced displacement and migration of people. Environmental changes such as drought, loss of agricultural land or rising sea levels are forcing people to leave their homes. This leads to internal displacement, cross-border displacement, or mass migration.
The WMO says early warning systems are critical to saving lives before natural disasters strike. It says these systems are more important than ever to protect people from the extreme weather conditions associated with human-induced climate change.
The World Meteorological Organization (WMO) is an intergovernmental organization with 193 member states and territories. Established on March 23, 1950, it is a United Nations agency specializing in meteorology (weather and climate), operational hydrology and related geophysical sciences, with headquarters in Geneva.
The Copernicus Climate Change Service (C3S) supports society by providing reliable information on past, present and future climate in Europe and the rest of the world. Its mission is to support the adaptation and mitigation policies of the European Union (EU). Based in Bonn, Germany, C3S is one of the information services provided by the EU's Copernicus Earth Observation Program.
World Weather Attribution is an academic working group that deals with the attribution of extreme events, i.e. the calculation of the effects of climate change on extreme meteorological events such as heat waves, droughts and storms. When an extreme event occurs, the project calculates the probability that the occurrence, intensity and duration of the event can be attributed to climate change. Partners are Imperial College London, the Royal Netherlands Meteorological Institute (KNMI) and the Red Cross Red Crescent Climate Center.
Further information
Full text: Global temperature record streak continues, as climate change makes heatwaves more extreme, World Meteorological Organization (WMO), press release, published May 15, 2024
https://wmo.int/media/news/global-temperature-record-streak-continues-climate-change-makes-heatwaves-more-extreme
Full text: Climate change made the deadly heatwaves that hit millions of highly vulnerable people across Asia more frequent and extreme, World Weather Attribution, analysis, released May 14, 2024
https://www.worldweatherattribution.org/climate-change-made-the-deadly-heatwaves-that-hit-millions-of-highly-vulnerable-people-across-asia-more-frequent-and-extreme/