Climat: Explaining Why the World Record for Average Earth Temperature Was Broken Twice This Week
Climate change continues to make headlines as the world experiences unprecedented heatwaves and record-breaking temperatures. June 2023 has been recorded as the hottest month ever, with an average temperature of 16.51°C, surpassing the previous record set in 2019 by 0.53°C.
🌍🔥🌡️ This week, the world broke the daily temperature record!— World Meteorological Organization (@WMO) July 7, 2023
🌡️🔥 According to @CopernicusECMWF's #ERA5 dataset, the global average 2m temperature hit 17.03°C on 4th July! 📈🌡️
Stay tuned for further updates from @WMO #StateofClimate
🔗 https://t.co/7ScabFvIG4 pic.twitter.com/7goNPhEnXg
The summer of 2023 is shaping up to be a season of alarming temperature records. The European Climate Change Observatory, Copernicus, announced on Thursday, July 6th, that June was the hottest month ever recorded globally. The average global temperature for the month was 16.51°C, which is 0.53°C higher than the average of the previous three decades. The previous record, set in June 2019, was only 0.37°C above these norms.
This trend continues into July. Tuesday saw the hottest day ever recorded globally, with an average temperature of 17.03 degrees, confirmed by Copernicus based on preliminary measurements. On Monday, another record was already broken, with an average temperature of 16.88 degrees across the globe (land and sea combined). Here's why these alarming records were broken.
High Ocean Surface Temperatures
The global temperature record for June is largely due to very high ocean surface temperatures, which cover more than 70% of the Earth's surface, explains Julien Nicolas, a scientist for Copernicus. "One factor is the lower wind speeds in large areas of the North Atlantic, due to a weak Azores high-pressure system, the weakest for a June since 1940. This reduced the mixing of surface waters and therefore their cooling."
Marine temperatures had already reached record levels in May in the Pacific Ocean. In June, the North Atlantic also experienced marine heatwaves, which "surprised many people by reaching truly unprecedented levels," according to the expert. "Extreme marine heatwaves" were also recorded in the Baltic Sea, as well as around Ireland and Great Britain, which had already confirmed its record-breaking June, significantly above the previous one. Additionally, there is the ongoing trend of ocean warming, with 90% of the heat produced by human activity being absorbed by the oceans, adds Julien Nicolas.
El Nino Phenomenon
The increase in ocean surface temperatures is partially due to the onset of El Niño. This climatic phenomenon occurs cyclically but irregularly, every three to seven years, and its episodes last from nine to twelve months, according to the World Meteorological Organization (WMO). It also leads to climate disasters, including droughts and above-average precipitation.
El Niño, which will continue throughout the year at least at a moderate intensity, according to the WMO, is expected to further contribute to rising temperatures in the coming months. "The arrival of El Niño will significantly increase the probability of breaking temperature records and triggering more extreme heat in many regions of the world and in the oceans," warned Petteri Taalas, the Secretary-General of the UN agency, in the organization's bulletin on Tuesday.
Human Activities Warming the Earth
Beyond these meteorological factors, these record-breaking temperatures on the Earth's surface are evidence of climate change caused by human activities. Humanity's greenhouse gas emissions continue to rise, as evidenced by data from the Our World in Data platform, led by the University of Oxford.
The situation is alarming and proves that "climate change is out of control," warned UN Secretary-General Antonio Guterres on Thursday. "If we continue to postpone the necessary measures [to reduce greenhouse gas emissions], we are heading towards a catastrophic situation," he cautioned.
While these temperature increases are concerning, they do not surprise scientists. Chloé Maréchal, a paleoclimatologist at the University of Lyon, notes that this phenomenon is "striking and has no equivalent in past situations." It is "entirely consistent with the increase in human-caused greenhouse gases in the atmosphere," she explained on BFMTV. According to the researcher, this rise in temperatures is "completely consistent with climate models that have been running for about a decade."
The situation is unlikely to improve, as confirmed by the findings of the Intergovernmental Panel on Climate Change's (IPCC) sixth report, published in March. The report estimates that human activities have caused a temperature increase of 1.07°C between 2010 and 2019. "Current trends are not at all compatible with stabilizing global warming, which would ensure a livable and equitable world. Efforts have been made, but they are not sufficient in scale for a rapid enough reduction in greenhouse gas emissions," warned climatologist Valérie Masson-Delmotte in an interview with France24 in March.