Leeds Professors: “Only 3 years left” to Avert Climate Catastrophe

Essay by Eric Worrall

Yet another climate deadline.

Only 3 years left – new study warns the world is running out of time to avoid the worst impacts of climate change

Published: July 20, 2025 2.20pm AEST

1. Piers Forster Professor of Physical Climate Change; Director of the Priestley International Centre for Climate, University of Leeds
2. Debbie Rosen Research and Innovation Development Manager for the Priestley Centre for Climate Futures, University of Leeds

Bad climate news is everywhere.  Africa is being hit particularly hard by climate change and extreme weather, impacting lives and livelihoods.

We are living in a world that is warming at the fastest rate since records began. Yet, governments have been slow to act.

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But so far, only 25 countries, covering around 20% of global emissions, have submitted their plans, known as Nationally Determined Contributions. In Africa, they are Somalia, Zambia and Zimbabwe. This leaves 172 still to come. 

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But arguably only one of the submitted plans – the UK’s – is compatible with the Paris Agreement.

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Our report shows that human-caused global warming reached 1.36°C in 2024. This boosted average global temperatures (a combination of human-induced warming and natural variability in the climate system) to 1.52°C. In other words, the world has already reached the level where it has warmed so much that it cannot avoid significant impacts from climate change. There is no doubt we are in dangerous waters.

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Just five of the G20 countries have submitted their 2035 plans: Canada, Brazil, Japan, the United States and the United Kingdom. But the G20 is responsible for around 80% of global emissions. This means that South Africa’s current G20 presidency can help to ensure that the world prioritises efforts to help developing countries finance their transition to a low-carbon economy.

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Read more: https://theconversation.com/only-3-years-left-new-study-warns-the-world-is-running-out-of-time-to-avoid-the-worst-impacts-of-climate-change-261229

The referenced “our report”;

Indicators of Global Climate Change 2024: annual update of key indicators of the state of the climate system and human influence

Piers M. Forster,Chris Smith,Tristram Walsh,William F. Lamb,Robin Lamboll,Christophe Cassou,Mathias Hauser,Zeke Hausfather,June-Yi Lee,Matthew D. Palmer,Karina von Schuckmann,Aimée B. A. Slangen,Sophie Szopa,Blair Trewin,Jeongeun Yun,Nathan P. Gillett,Stuart Jenkins,H. Damon Matthews,Krishnan Raghavan,Aurélien Ribes,Joeri Rogelj,Debbie Rosen,Xuebin Zhang,Myles Allen,Lara Aleluia Reis,Robbie M. Andrew,Richard A. Betts,Alex Borger,Jiddu A. Broersma,Samantha N. Burgess,Lijing Cheng,Pierre Friedlingstein,Catia M. Domingues,Marco Gambarini,Thomas Gasser,Johannes Gütschow,Masayoshi Ishii,Christopher Kadow,John Kennedy,Rachel E. Killick,Paul B. Krummel,Aurélien Liné,Didier P. Monselesan,Colin Morice,Jens Mühle,Vaishali Naik,Glen P. Peters,Anna Pirani,Julia Pongratz,Jan C. Minx,Matthew Rigby,Robert Rohde,Abhishek Savita,Sonia I. Seneviratne,Peter Thorne,Christopher Wells,Luke M. Western,Guido R. van der Werf,Susan E. Wijffels,Valérie Masson-Delmotte,and Panmao Zhai

Abstract

In a rapidly changing climate, evidence-based decision-making benefits from up-to-date and timely information. Here we compile monitoring datasets (published at https://doi.org/10.5281/zenodo.15639576; Smith et al., 2025a) to produce updated estimates for key indicators of the state of the climate system: net emissions of greenhouse gases and short-lived climate forcers, greenhouse gas concentrations, radiative forcing, the Earth’s energy imbalance, surface temperature changes, warming attributed to human activities, the remaining carbon budget, and estimates of global temperature extremes. This year, we additionally include indicators for sea-level rise and land precipitation change. We follow methods as closely as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One report.

The indicators show that human activities are increasing the Earth’s energy imbalance and driving faster sea-level rise compared to the AR6 assessment. For the 2015–2024 decade average, observed warming relative to 1850–1900 was 1.24 [1.11 to 1.35] °C, of which 1.22 [1.0 to 1.5] °C was human-induced. The 2024-observed best estimate of global surface temperature (1.52 °C) is well above the best estimate of human-caused warming (1.36 °C). However, the 2024 observed warming can still be regarded as a typical year, considering the human-induced warming level and the state of internal variability associated with the phase of El Niño and Atlantic variability. Human-induced warming has been increasing at a rate that is unprecedented in the instrumental record, reaching 0.27 [0.2–0.4] °C per decade over 2015–2024. This high rate of warming is caused by a combination of greenhouse gas emissions being at an all-time high of 53.6±5.2 Gt CO₂e yr⁻¹ over the last decade (2014–2023), as well as reductions in the strength of aerosol cooling. Despite this, there is evidence that the rate of increase in CO₂ emissions over the last decade has slowed compared to the 2000s, and depending on societal choices, a continued series of these annual updates over the critical 2020s decade could track decreases or increases in the rate of the climatic changes presented here.

 – Discussion started: 05 May 2025

 – Revised: 11 Jun 2025

 – Accepted: 13 Jun 2025

 – Published: 19 Jun 2025

Read more: https://essd.copernicus.org/articles/17/2641/2025/

You have to delve into the study to find the 3 years reference;

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The values in Table 8 are all greater than zero, implying that we have not yet emitted the amount of CO₂ that would commit us to these levels of warming. However, including the uncertainty in ZEC (as in Table S8), non-CO₂emission and forcing uncertainty, and underrepresented Earth system feedbacks results in negative RCB estimates for limiting warming to low temperature limits with high likelihood. A negative RCB for a specific temperature limit would mean that the world is already committed to this amount of warming and that net negative emissions would therefore be required to return to the temperature limit after a period of overshoot. The assumption behind such a calculation is that we can treat the warming impact of positive and negative net emissions as approximately symmetric. While the claim of symmetry is likely valid for small emissions values, some model studies have shown that it holds less well for reversal of larger emissions (Canadell et al., 2021; Zickfeld et al., 2021; Vakilifard et al., 2022; Pelz et al., 2025). As such, larger exceedances of the RCB for a particular temperature target would decrease the likelihood that the temperature target could still be achieved by an equivalent amount of net negative emissions.

Note that the 50 % RCB estimate of 130 Gt CO₂ would be exhausted in a little more than 3 years if global CO₂ emissions remain at 2024 levels (42 Gt CO₂ yr⁻¹; see Table 1). This is not expected to correspond exactly to the time that 1.5 °C global warming level is reached due to uncertainty associated with committed warming from past CO₂ emissions (the ZEC) as well as ongoing warming and cooling contributions from non-CO₂ emissions. For comparison, our estimate of 2024 anthropogenic warming (1.36 °C) and the recent rate of increase (0.27 °C per decade) would suggest that continued emissions at current levels would cause human-induced global warming to reach 1.5 °C in approximately 5 years.

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Read more: Same link as above

This deadline will no doubt join all the other 3 years or 5 years or 10 years to save the world nonsense deadlines which have come and gone. Even if we wanted to there is no plausible path to meaningfully reducing emissions in such a short timeframe.

The world has already touched 1.5C global warming, and nothing bad happened. This appears to have prompted some rather panicked spin, at least in some quarters, to downgrade 1.5C to more of a guideline than a climate emergency.

The most interesting part of the article for me was the reference to the US nationally determined contributions plan for 2035, which was submitted in December 2024 by the Biden administration. The Biden plan committed the USA to a 61-65% reduction in emissions compared to 2005.

That submission was effectively rendered null and void by President Trump’s withdrawal from the Paris Agreement. Perhaps in the UN bubble world the authors of the quoted article inhabit, the USA is still a full Paris Agreement partner. Or maybe they think President Trump is an anomaly, a brief pushback by conservative reactionaries before the inevitable return of business as usual.