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Greenhouse gases reached another record high in 2023, warns UN weather agency
New data released by the UN on Monday indicating that greenhouse gases have hit a record high shows once again that urgent action and not words is needed from the world’s major polluters to protect us all from climate change, the World Meteorological Organization (WMO) insisted.
The appeal comes as global leaders prepare to gather for the UN’s Climate Change Conference in Baku next month, amid repeated dire warnings about the human cost of ignoring the existential crisis from UN Secretary-General António Guterres and others.
Echoing the UN chief’s longstanding appeals, WMO Deputy Secretary-General Ko Barrett told journalists that carbon dioxide (CO2) – one of the three main greenhouse gases, along with methane and nitrous oxide - is now accumulating in the atmosphere “faster than at any time experienced during human existence”. Because of the extremely long lifetime of CO2 in the atmosphere, “we are committed to rising temperatures for many, many years to come”, she added.
WMO’s 2024 Greenhouse Gas Bulletin offers a stark, scientific reminder that rising CO2 levels need to be slowed. In 2004, the concentration of carbon dioxide in the atmosphere was 377.1 parts per million (ppm), while in 2023, this reached 420 ppm, according to WMO’s Global Atmosphere Watch Network. “This is an increase of 42.9 parts per million, or 11.4 per cent in just 20 years,” Ms. Barrett explained.
“These are more than statistics," the WMO deputy chief insisted. "Every part per million matters, every fraction of a degree of temperature increase matters; it matters in terms of the speed of glacier and ice retreat, the acceleration of sea level rise, ocean heat and acidification. It matters in terms of the number of people who will be exposed to extreme heat every year, the extinction of species, the impact on our ecosystems and economies.”
Key greenhouse gas-producing events include forest fires and the El Niño weather phenomenon which fuelled drier conditions and a “surge” in concentrations in the latter part of 2023, according to WMO. Its analysis shows that just under half of CO2 emissions remain in the atmosphere, just over one quarter are absorbed by the ocean and just under 30 per cent are retained on land.
Senior scientific officer at WMO, Oksana Tarasova, described last year’s wildfires in Canada as “absolutely dramatic” in terms of the amount of greenhouse gases produced.
Today’s CO2 levels have not been seen “in the history of humanity”, she said. “The last time we see 400 parts per million of CO2 was three to five million years ago, and during that time, the temperature was three to four degrees warmer” and sea levels 10-20 metres higher.
The WMO report pointed out that from 1990 to 2023, radiative forcing – the warming effect on our climate from greenhouse gases increased by 51.5 per cent. CO2 accounted for more than 80 per cent of this increase, according to data from the National Oceanic and Atmospheric Administration Annual Greenhouse Gas Index.
“As long as emissions continue, greenhouse gases will continue accumulating in the atmosphere leading to global temperature rise,” the UN agency said. “Given the extremely long life of CO2 in the atmosphere, the temperature level already observed will persist for several decades even if emissions are rapidly reduced to net zero.”
Asked about whether the UN climate conference might be expected to yield tangible commitments from countries, the WMO Deputy Secretary-General noted that politicians worldwide do reference the latest scientific climate findings and forecasts in their public declarations. “So I do think they are listening, the question is to what degree will we see that manifest at COP29 in action,” she said.
Ms. Barrett noted that measures taken at a national level to transition to a “lower fossil fuel economy” were massively important to safeguard future generations.
“Even though there is a lag and temperatures will rise, we are not to be dissuaded from action,” she said, “because there will be a transformation and a downward trend in temperature in future. It all just depends on how quickly we take action and how fast we can reduce those temperatures.”
Story: Record greenhouse gas levels - WMO
Speakers:
Ko Barrett, WMO Deputy Secretary-General
Oksana Tarasova, Senior scientific officer, WMO
TRT: 0x’”
SOURCE: UNTV CH
LANGUAGE: ENGLISH / NATS
ASPECT RATIO: 16:9
DATELINE: 28 October 2024 - GENEVA, SWITZERLAND
RESTRICTIONS: None
SHOTLIST
- Exterior medium shot: UN flag alley.
- Wide shot of the press conference room with speakers at the podium.
- SOUNDBITE (English) Ko Barrett, Deputy Secretary-General, World Meteorological Organization (WMO): “Carbon dioxide is accumulating in the atmosphere faster than at any time experienced during human existence, and because of the extremely long lifetime of CO2 in the atmosphere we are committed to rising temperatures for many, many years to come.”
- Medium shot of the podium’s speakers.
- SOUNDBITE (English) Ko Barrett, Deputy Secretary-General, World Meteorological Organization (WMO): “These are more than statistics; every part per million matters, every fraction of a degree of temperature increase matters; it matters in terms of the speed of glacier and ice retreat, the acceleration of sea level rise, ocean heat and acidification. It matters in terms of the number of people who will be exposed to extreme heat every year, the extinction of species, the impact on our ecosystems and economies.”
- Medium shot, TV screen showing CO2 dataset and graph with automatic TV camera in shot.
- SOUNDBITE (English) Ko Barrett, Deputy Secretary-General, World Meteorological Organization (WMO): “Yet again, unfortunately, we have to report that the main greenhouse gases, CO2, methane and nitrous oxide are all at record levels. In 2004, the concentration of carbon dioxide in the atmosphere was 377.1 parts per million. In 2023, 20 years later, it was at 420 parts per million, according to data from WMO’s Global Atmosphere Watch Network. This is an increase of 42.9 parts per million, or 11.4 per cent in just 20 years.”
- Medium-wide shot of speakers and Press room.
- SOUNDBITE (English) Oksana Tarasova, Senior scientific officer, WMO: “We have not seen these levels of CO2 in the history of humanity. The last time we see 400 parts per million of CO2 was three to five million years ago, and during that time, the temperature was three to four degrees warmer.”
- Medium, journalist typing on laptop.
- SOUNDBITE (English) Ko Barrett, Deputy Secretary-General, World Meteorological Organization (WMO): “The reason you’re seeing such variations even in the projections of what temperature rise might be in our future, it’s because it’s very much linked to the actions countries take now and the rapid - the ability to - make a rapid transition to a lower fossil fuel economy. And even though there is a lag and temperatures will rise, we are not to be dissuaded from action, because there will be a transformation and a downward trend in temperature in future. It all just depends on how quickly we take action and how fast we can reduce those temperatures.”
- Medium, podium speakers, UN logo as backdrop.
- SOUNDBITE (English) Ko Barrett, Deputy Secretary-General, World Meteorological Organization (WMO): “Personally, I see a lot of attention to science in the statements that are being made from politicians worldwide. So I do think they are listening, the question is to what degree will we see that manifest at COP29 in action.”
- Medium shot of TV screen showing data on greenhouse gas concentrations.
- Wide shot, Press room, TV screens showing Ms. Barrett and dataset.
- Medium shot, TV screen showing greenhouse gases dataset and graph with automatic TV camera in shot.
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Glaciers disappearing
In 2025, for the fourth consecutive year, every major glaciated region on Earth lost ice mass, leading to short-term hazards including floods and long-term water insecurity, according to WMO.
Responding to a question about whether the changing global water cycle might have contributed to the deadly Nepal-China flooding disaster, Ms. Saulo explained that melting ice and rock was just one factor in the chain of events that ultimately sent a massive and deadly wall of water and debris downstream on 26 August, killing at least 1,367 people.
“You asked if it could happen again? Absolutely; the problem in this region is that there’s 63,700 glaciers at the last count,” she told a Press Conference in Geneva. “Even if you’re looking with remote sensing with satellites at these glaciers, you might see some faults, you might see some slight shifting, that does not mean necessarily catastrophic collapse. So, in order to plan for this, it’s very, very difficult. But the international community is looking very hard at ways in which we can bring people together to solve some of these monitoring issues.”
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Preparing for moving baselines
The report does not attribute every observed change to climate change alone. WMO says pressure on water resources and natural variability also contribute.
Mr. Jenkinson said governments need to prepare for “moving baselines” as historical patterns become less reliable.
“The situation 30 years ago is not where we are today,” he said. Countries, he added, need to prepare “for those changes that have really already arrived”.
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