2023 in climate change


This article documents events, research findings, scientific and technological advances, and human actions to measure, predict, mitigate, and adapt to the effects of global warming and climate change—during the year 2023.

Summaries

  • 6 February: U.N. Secretary-General António Guterres said "I have a special message for fossil fuel producers and their enablers scrambling to expand production and raking in monster profits: If you cannot set a credible course for net-zero, with 2025 and 2030 targets covering all your operations, you should not be in business."
  • 20 March – The final synthesis of the IPCC Sixth Assessment Report is published. It summarises the state of knowledge relating to climate change with assessed levels of confidence. Conclusions in the summary for contemporary policy-makers include that the extent to which both current and future generations will be impacted depends on choices now and in the near-term, with "high confidence" that policies implemented by the end of 2020 are "projected to result in higher global GHG emissions in 2030 than emissions implied by NDCs" and would fail to meet global climate goals.
  • 6 September: U.N. Secretary-General António Guterres said "Our planet has just endured a season of simmering — the hottest summer on record. Climate breakdown has begun."
  • 24 October: BioScience's "2023 state of the climate report" stated that "we must shift our perspective on the climate emergency from being just an isolated environmental issue to a systemic, existential threat".
  • 27 December: Inside Climate News summarized the year: "The push and pull of progress and catastrophe made 2023 one of the most discordant—and consequential—years for the world's climate.... In 2023, clean energy progress and the horrors of a radically warming climate fought almost to a draw."

Measurements and statistics

Natural events and phenomena

  • 7 February: a study published in Nature Communications concluded that 15 million people globally are exposed to impacts from potential glacial lake outburst floods, more than half being from India, Pakistan, Peru, and China. Climate change has intensified glacial ice melt and expanded glacial lakes.
  • 13 February: a study published in the Proceedings of the National Academy of Sciences reported that increasing abundance of a thermotolerant symbiotic alga hosted by corals has facilitated maintenance of high coral cover after three mass coral bleaching events, suggesting that future reefs might maintain high cover for several decades, albeit with low diversity and provided that other stressors are minimized.
  • 2 March: a study published in Science said that boreal fires, typically accounting for 10% of global fire emissions, contributed 23% in 2021, by far the highest fraction since 2000. 2021 was an abnormal year because North American and Eurasian boreal forests synchronously experienced their greatest water deficit.
  • 13 March: a study published in Nature Water found that total intensity of extreme events is strongly correlated with global mean temperature, and concluded that continued warming of the planet will cause more frequent, more severe, longer and/or larger of such extreme events, and that "distortion of the water cycle... will be among the most conspicuous consequences of climate change".
  • 15 February: Two joint studies by the British Antarctic Survey and the US Antarctic programme finds that glaciers on the icy continent may be more sensitive to changes in sea temperature than previously thought. Researchers used sensors and an underwater robot beneath the Thwaites glacier to study melting. One day earlier, a new record low Antarctic sea ice extent is reported by the National Snow and Ice Data Center in the US, beating the previous record set a year earlier.
  • 29 March: a study published in Nature concluded that under a high-emissions scenario, abyssal warming is set to accelerate over the next 30 years, and that meltwater input around Antarctica drives a contraction of Antarctic Bottom Water, opening a pathway that allows warm circumpolar deep water greater access to the continental shelf and results in warming and aging of the abyssal ocean. The study described the "critical importance of Antarctic meltwater in setting the abyssal ocean overturning, with implications for global ocean biogeochemistry and climate that could last for centuries". On 25 May, observational evidence for problematic fast slowdown of the Antarctic bottom water current is presented in Nature Climate Change.
  • 7 April: citing reduced air density caused by global warming, a study published in the Bulletin of the American Meteorological Society estimated global warming has enabled more than 500 excess home runs in Major League Baseball since 2010, and projected hundreds more in this century, explaining that "even the elite billion-dollar sports industry is vulnerable to unexpected impacts" of global warming.
  • 5 June: a study published in Current Biology estimated that fungi can fix the equivalent of ~36% of global fossil fuel Greenhouse gas emissions.
  • 8 June: NOAA published an "ENSO update" declaring that "El Niño is here", estimating the odds of it becoming a strong event, at least a moderate event, and "fizzling out".
  • 11 June: Fluchthorn, a mountain between Switzerland and Austria, experienced a landslide of and a loss of in height, that has been attributed to melting of permafrost.
  • 20 June : the Panama Canal is experiencing its lowest rainfall since inception, lowering water levels and requiring restrictions for some vessels to limit their cargo by about 25% to maintain a safe draft and avoid running aground.
  • 4 July: the WMO formally declared "onset of El Niño conditions", projecting it to be "at least of moderate strength".
  • 11 July: a study of Chicago structures published in Communications Engineering found that in urban settings, subsurface heat islands caused by global warming cause significant deformations and displacements that may be "incompatible with the operational requirements of civil structures".
  • 28 July: Yale Environment 360 reported that, adding to ongoing climate change's dominant warming influence, additional factors contributing to current temperature increases include: 2022 eruption of an underwater volcano near Tonga, vaporizing large amounts of sea water and contributing an estimated of warming, solar radiance increasing towards its ~2025 11-year peak when it may contribute of warming, and the Pacific Ocean entering its El Niño phase, projected to contribute of warming.
  • 23 August : the Panama Canal experienced an unprecedented dry season causing a decline in water levels and prompting canal administrators to limit daily vessel passages from 36 to 32, and forcing some ships to carry up to 40% less cargo to avoid hitting the bottom.
  • 24 August: a study published in Nature Communications concluded that tropical cyclone rapid intensification events in offshore areas within of coastlines, tripled in frequency from 1980 to 2020.
  • 8 September : for the first time in recorded history, all seven tropical ocean basins saw cyclones/hurricanes reach Category 5 strength in the same year.
  • 13 September: a study published in Communications Earth & Environment concluded that, while for many years Antarctic sea ice had increased, from recent record lows in Antarctic sea ice coverage "it appears that we may now be seeing the inevitable decline, long projected by climate models", and that a "regime shift" may be taking place "in which previously important relationships no longer dominate sea ice variability".
  • 13 September: a study published in Science Advances indicated that six of the nine "planetary boundaries"—delimiting the "safe operating space"—had been exceeded. Carbon dioxide concentration and radiative forcing were among the boundaries that had been exceeded.
  • 27 September: studying tropical cyclones from 1981–2017, a study published in Nature found that cyclones formed almost two weeks sooner, on average, which authors said was "closely related to the seasonal advance of rapid intensification events". The time advance shifts cyclones from autumn into summer, increasing overlap with the peak rainfall season.
  • 6 December: a study published in Nature Geoscience said that marine methane hydrate—an ice-like substance found in sediment beneath water depths greater than ~450–700 m—can vent into the ocean to such a degree that it should considered for estimating climate change-induced release of methane, a greenhouse gas.

Actions and goal statements

Science and technology

Political, economic, legal, and cultural actions

Mitigation goal statements

  • 15 April: a communique from a meeting of G7 ministers pledged to collectively increase offshore wind capacity by 150 gigawatts by 2030 and solar capacity to more than 1 terawatt, and agreed to accelerate the phase-out of unabated fossil fuels to achieve net zero by 2050. They stopped short of endorsing a 2030 deadline for phasing out coal, and left the door open for continued investment in gas to help address potential energy shortfalls.
  • 19 May: a policies study review in One Earth, based on a systematic examination of existing methane policies across sectors, concludes that both only "about 13% of methane emissions are covered by methane mitigation policies and that the effectiveness of these policies "is far from clear".

Consensus

  • 8 June: a study published in PLOS Climate studied defensive and secure forms of national identity—respectively called "national narcissism" and "secure national identification"—for their correlation to support for policies to mitigate climate change and to transition to renewable energy. The researchers concluded that secure national identification tends to support policies promoting renewable energy; however, national narcissism was found to be inversely correlated with support for such policies—except to the extent that such policies, as well as greenwashing, enhance the national image. Right-wing political orientation, which may indicate susceptibility to climate conspiracy beliefs, was also concluded to be negatively correlated with support for genuine climate mitigation policies.
  • 7 August: A global survey study of climate policy researchers, published in Nature Sustainability, finds these experts substantially doubt the prevailing green growth narrative, "underscor the importance of considering alternative post-growth perspectives" that include approaches of agrowth and degrowth.

Projections

  • 2 January: a study published in Earth's Future (American Geophysical Union) concluded that the greatest increase in the amount of coastal area below mean sea level will occur in the early stages of sea level rise, contrary to earlier assessments, shortening time for adaptation efforts. Latest projections indicate that SLR is certain to exceed in coming centuries, and a rise by is considered possible.
  • 5 January: a study published in Science stated that, based on then-current pledges, global mean temperature is projected to increase by +2.7 °C, which would cause loss of about half of Earth's glaciers by 2100, causing a sea level rise of 115±40 millimeters.
  • 30 January: Climate scientists predict, using artificial intelligence, in Proceedings of the National Academy of Sciences that global warming will exceed 1.5 °C, and a nearly 70% chance of 2 °C between 2044 and 2065 —a substantial probability of exceeding the 2 °C threshold—even if emissions rapidly decline.
  • 30 January: A study in Nature Sustainability outlines challenges of aviation decarbonization by 2050 whose identified factors mainly are future demand, continuous efficiency improvements, new short-haul engines, higher SAF (biofuel) production, removal to compensate for non- forcing, and related policy-options. With constant air transport demand and aircraft efficiency, decarbonizing aviation would require nearly five times the 2019 worldwide biofuel production, competing with other hard-to-decarbonize sectors and land-use. — News article about the study:
  • 6 February: A study in Nature Climate Change integrates policy as an aspect into an integrated assessment model, showing that Powering Past Coal Alliance-based coal phase-out is highly unlikely with current policies where both coal-use would substantially only shift from power to other industries and China will now potentially "dangerously delay" the phase-out.
  • February: the International Energy Agency's Electricity Market Report 2023 projected that low-emissions sources will constitute almost all the growth in global electricity demand through 2025, with renewables' portion of global power generation rising from 29% in 2022 to 35% in 2025.
  • 6 March: The highest-granularity study on food GHGs, published in Nature Climate Change, reports that global food consumption failed climate goals with constant patterns, with ~75% of the projected warming due to ruminant meat, dairy and rice, albeit consumption currently shifts towards higher emissions overall as economic development is expected to facilitate acquisitions of undifferentiated goods like beef.
  • 13 March: a study published in Nature Sustainability forecast that floating photovoltaic systems on reservoirs could provide 9,434±29 terawatt-hours/year—over a third of global electricity.
  • 27 March: a study in Geophysical Research Letters attempts to provide of the tipping point(s) of the Greenland ice sheet.
  • 5 April: in its Boom and Bust Coal publication, Global Energy Monitor stated that phasing out operating coal power by 2040 would require an average of 117 GW of retirements per year—4.5 times the capacity retired in 2022. An average of 60 GW/yr for OECD countries, and 91 GW/year for non-OECD countries, must come offline.
  • 17 May: the WMO Global Annual to Decadal Climate Update projected that the chance of global near-surface temperature exceeding 1.5 °C above preindustrial levels for at least one year between 2023 and 2027 is 66%, though it is unlikely that the five-year mean will exceed 1.5 °C.
  • 20 May: a study published in One Earth found that increased temperature delays sleep onset and increases the probability of insufficient sleep, estimating that global warming may erode 50–58 hours of sleep per person-year while producing geographic inequalities that scale with future emissions.
  • 22 May: a study published in Nature Sustainability projected that current policies leading to ~2.7 °C global warming could leave 22–39% of humans outside their "human climate niche"—defined as "the historically highly conserved distribution of relative human population density with respect to mean annual temperature." The study projected that reducing warming from 2.7 to 1.5 °C would result in a ~5-fold decrease in population exposed to unprecedented heat.
  • 6 June: a study published in Nature Communications projected that under all SSP emissions scenarios considered, the Arctic would be ice-free in September as soon as the 2030s, sooner than the IPCC's earlier projection of mid-century.
  • 7 June: the American Lung Association projected that, by 2050, as the U.S. moves to 100 percent zero emission new passenger vehicles sales and clean electricity generation, the resulting cleaner air could bring $978 billion in public health benefits, 89,300 fewer premature deaths, 2.2 million fewer asthma attacks, and 10.7 million fewer lost workdays.
  • 14 June: the International Energy Agency's Oil 2023: Analysis and forecast to 2028 said that demand for oil from combustible fossil fuels is on course to peak in 2028, and that growth is set to reverse after 2023 for gasoline and after 2026 for transport fuels overall.
  • 25 July: a study published in Nature Communications projected a tipping point collapse of the Atlantic meridional overturning circulation by mid-century, causing long term cooling of Europe. Earlier IPCC projections were that such a collapse is not likely within the century.
  • 19 August: a study published in Energies projected that global warming reaching 2 °C this century will cause premature deaths in roughly 1 billion humans. The study cited the order-of-magnitude estimate in the "1000-ton rule" that states that a future person is killed every time 1,000 tons of fossil carbon are burned.
  • 28 August: a study published in Nature Climate Change projected that without snowmaking, 53% of ski resorts in 28 European countries will be at "very high risk for snow supply" under global warming of 2 °C.
  • 5 September: A study in The Lancet Planetary Health shows decoupling rates in high-income countries are inadequate for Paris Agreement commitments and suggests post-growth approaches such as demand reduction strategies and reorienting the economy.
  • 2 October: a study published in Nature Communications studied the effect of the expected reduction in the amount of dark-colored, light-absorbing atmospheric particles that snow would absorb, making the snow reflect more sunlight, thus reducing radiative forcing that would otherwise warm the Earth. The study concluded that there would be a reduction in radiative forcing from 0.65W/m2 to 0.49 W/m2.
  • 23 October: a Washington Post analysis concluded that by 2040, longer warm and moist transmission seasons and expanding habitats for mosquitos, coupled with expected demographic growth, could put more than 5 billion people at risk of contracting malaria.
  • 23 October: a study published in Nature Climate Change projected that ocean warming at about triple the historical rate is likely unavoidable in the 21st century, with no significant difference between mid-range emissions scenarios versus achieving the most ambitious targets of the Paris Agreement—suggesting that greenhouse gas mitigation has limited ability to prevent collapse of the West Antarctic Ice Sheet.
  • 24 October: the International Energy Agency's World Energy Outlook 2023 stated that "the momentum behind clean energy transitions is now sufficient for global demand for coal, oil and natural gas to all reach a high point before 2030 in the STEPS".
  • 2 November: a study published in Oxford Open Climate Change projected that the recent decline of aerosol emissions should increase the global warming rate of 0.18°C per decade to at least 0.27°C per decade, so that "under the present geopolitical approach to GHG emissions", warming will exceed 1.5°C in the 2020s and 2°C before 2050.
  • 5 December: a report from the United Nations Environment Programme projected that on current growth trends, electricity for cooling equipment would more than double by 2050, and that under a business-as-usual scenario, emissions from cooling would account for more than 10% of global emissions in 2050.

Significant publications

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  • 14 November: , U.S. Global Change Research Program.
  • 30 November:
  • 19 March 2024: WMO-No. 1347.

Organizations

  • at the U.S. Environmental Protection Agency

Surveys, summaries and report lists

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