Global temperatures have reached exceptionally high levels in 2023. The service Copernicus Climate Change Service (C3S)implemented by European Weather Forecasting Centre medium-term on behalf of the European Commission with EU funding, monitored several key climate indicators throughout the year: unprecedented global temperatures from June onwards led to 2023 becoming the warmest year on record, surpassing 2016 by a wide margin.
According to the 2023 Global Climate Highlights report, in 2023 the global average temperature was 14.98 C, 0.17 C higher than the previous highest annual value in 2016. 2023 was 0.60 C warmer than the 1991-2020 average and 1.48 C warmer than the 1850-1900 pre-industrial level. It is probable that in the end the figure will exceed the fateful threshold of +1.5 degrees above the pre-industrial level.
Furthermore, in 2023 for the first time every day had a temperature at least one degree higher than the pre-industrial era, and almost half of the days were more than 1.5 C warmer than the 1850-1900 level, and two days at November was, for the first time, more than 2 C warmer. Average annual air temperatures were the warmest on record, or close to the warmest, over large parts of all ocean basins and all continents except Australia.
Every month from June to December in 2023 was warmer than the corresponding month in any previous year, and July and August 2023 were the two warmest months on record. The boreal summer (June-August) was also the warmest season on record. September 2023 was the month with a greater temperature deviation above the 1991-2020 average than any other month in the ERA5 dataset.
December 2023 was the warmest December on record globallywith an average temperature of 13.51 C, 0.85 C above the 1991-2020 average and 1.78 C above the 1850-1900 level for the month.
Global mean sea surface temperatures (SSTs) have remained persistently and unusually high, reaching record highs for the April to December period of the year. 2023 saw the transition to El Nino. In the spring of 2023, La Nina ended and El Nino conditions began to develop, with the WMO declaring the onset of El Nino in early July.
As for Europe, temperatures were above average for 11 months in 2023 and September was the warmest September on record. The European winter (December 2022 – February 2023) was the second warmest winter on record. The average temperature for the European summer (June-August) was 19.63 C; at 0.83 C above average, it was the fifth warmest on record
. European autumn (September-November) had an average temperature of 10.96 C, which is 1.43 C above average. This made the autumn the second warmest on record, just 0.03 C colder than autumn 2020.
2023 was an extraordinary year for Antarctic sea ice: reached record minimum extensions for the corresponding period of the year in 8 months. Both daily and monthly extent reached record lows in February 2023. Arctic sea ice extent at its annual peak in March was ranked among the four lowest for the time of year in satellite data.
September’s annual low was the sixth lowest. Atmospheric concentrations of carbon dioxide and methane continued to increase and reached record levels in 2023, reaching 419 ppm and 1902 ppb, respectively. Carbon dioxide concentrations in 2023 were 2.4 ppm higher than in 2022, and methane concentrations increased by 11 ppb. Numerous extreme events have been recorded around the world, including heatwaves, floods, droughts and fires.
Estimated global carbon emissions from wildfires in 2023 increased by 30% compared to 2022, largely due to persistent wildfires in Canada. Mauro Facchini, head of Earth Observation at the Directorate General for Defense Industry and Space, European Commission, comments: «We knew thanks to the work of the Copernicus program throughout 2023 that we would not receive good news today. But the annual data presented here provides further evidence of the growing impact of climate change.
The European Union, in line with the best available science, has agreed to a 55% emissions reduction by 2030 – now just 6 years away. The challenge is clear. The Copernicus programme, managed by the European Commission, is one of the best tools available to guide our climate actions, keep us in line with the goals of the Paris Agreement and accelerate the green transition.”
Sima: with record heat, disease risks increase
Rising temperatures have direct effects on human health, and increase the risk of diseases transmitted through water, food, insects and parasites. This was stated by the experts of the Italian Society of Environmental Medicine (Sima), commenting on the alarm launched by Copernicus according to which 2023 is confirmed as the hottest year ever recorded since 1850, with the increase in the average global temperature close to the limit of 1.5 degrees centigrade.
Global warming alters the balance of all ecosystems, threatening the essential elements of human life such as water, air and food, and changes the frequency and distribution of many infectious diseases. – explains Sima – The increase in average temperatures creates the ideal conditions for the transmission of multiple pathogens: thanks to the greater humidity, for example, ticks, mosquitoes and parasites proliferate and spread even serious diseases such as the Zika virus, dengue fever and malaria .
But the risk of water-borne diseases is also growing: intense rains and floods, events directly connected to climate change, cause water courses to overflow and sewerage systems to go haywire, spreading viral agents such as hepatitis A and E viruses, Enterovirus, Adenovirus, Norovirus, Rotavirus among the population, contaminating also the food chain.
And right on the food front the rise in average temperatures increases the survival of cysts of pathogenic protozoa and the bacteria responsible for some gastrointestinal syndromesalso due to the contamination of some food products, such as fish products.
«These phenomena are associated with the psychological one, which must not be underestimated – states the Sima president, Alessandro Miani – The term “solastalgia” was recently coined to indicate the anguish caused by the drastic change in the climate: climatic events extremes cause a state of stress and anxiety among the most vulnerable citizens which can lead to post-traumatic disorders and even suicides.”