Greenhouse gas emissions at ‘an all-time high’ - and it is causing an unprecedented rate of global warming, say scientists

• Human-induced warming averaged 1.14°C over the last decade  

• A record level of greenhouse gases is being emitted each year, equivalent to 54 billion tonnes of carbon dioxide 

• The remaining carbon budget - how much carbon dioxide can be emitted to have a better than 50% chance of holding global warming to 1.5°C - has halved over three years  

• Leading scientists have today launched a project to update key climate indicators every year, so people can be kept informed about critical aspects of global warming  

Newswise — According to 50 eminent scientists, human-induced global warming has persistently accelerated at a "remarkable pace" since the previous extensive evaluation of the climate system released 24 months ago.

A researcher remarked that the analysis served as a "timely alert" highlighting the inadequacy of the current pace and scope of climate initiatives. This statement coincides with the gathering of climate experts in Bonn, who are working to lay the foundation for the significant COP28 climate conference scheduled for December in the UAE. The conference will involve an assessment of the progress made towards the objective of limiting global warming to 1.5°C by 2050.

Considering the rapidity of transformations occurring within the global climate system, the scientists contend that policymakers, climate negotiators, and civil society organizations must possess current and resilient scientific data to inform their decision-making processes.

The UN's Intergovernmental Panel on Climate Change (IPCC) serves as the primary and reputable provider of scientific information regarding the state of the climate. However, the significant assessments conducted by the IPCC have a turnaround time of five to ten years, resulting in an "information gap," particularly when climate indicators undergo rapid changes.

Under the leadership of the University of Leeds, the scientists have undertaken an initiative to establish an open data and open science platform called the Indicators of Global Climate Change (IGCC) and its corresponding website (https://igcc.earth/). This platform aims to provide annual updates on essential climate indicators, ensuring access to up-to-date information.

Critical decade for climate change 

Professor Piers Forster, Director of the Priestley Centre for Climate Futures at Leeds, is leading the coordination of the Indicators of Global Climate Change Project. Emphasizing the urgency, he stated, "This is the crucial decade for addressing climate change."

"The choices made at this moment will determine the extent of temperature increases and the nature and severity of consequent impacts," Professor Piers Forster explained, highlighting the significance of present decisions in shaping the future climate scenario.

"At present, the long-term warming rates have reached unprecedented levels, primarily driven by the highest-ever recorded greenhouse gas emissions. However, there are indications that the rate of greenhouse gas emission growth has started to decelerate," the scientists observed.

"In response to climate change, it is imperative that we remain adaptable and responsive. We must revise policies and approaches based on the most recent evidence concerning the state of the climate system. Time is no longer in our favor, and access to current information is of utmost importance," stressed the scientists, emphasizing the critical need for agility and access to up-to-date data in addressing the challenges posed by climate change.

In their publication in the journal Earth System Science Data, the scientists have unveiled the alterations in crucial indicators since the release of the IPCC's Sixth Assessment Working Group 1 report in 2021. These indicators served as the primary data source for the subsequent IPCC Sixth Synthesis Report.

What the updated indicators show  

Anthropogenic warming, predominantly attributed to the combustion of fossil fuels, has escalated to an average of 1.14°C above pre-industrial levels during the latest decade (2013 to 2022). This represents an increase from 1.07°C recorded between 2010 and 2019.

Human-induced warming is now increasing at a pace of over 0.2°C per decade.  

-The analysis further revealed that greenhouse gas emissions have reached an unprecedented peak, with human activities leading to an average annual release of approximately 54 (+/-5.3) gigatonnes (or billion metric tonnes) of carbon dioxide equivalent into the atmosphere during the last decade (2012-2021).

While there has been a notable shift away from coal combustion, it has come with a short-term consequence. The reduction in particulate pollution caused by this shift has inadvertently contributed to global warming. Particulate pollution in the air has a cooling effect, and its decline has resulted in a net increase in global warming.

‘Indicators critical to address climate crisis’ 

Professor Maisa Rojas Corradi, Minister of the Environment in Chile, an IPCC author, and a scientist engaged in this research, emphasized the significance of an annual update on key global change indicators. Such updates play a crucial role in ensuring that the international community and individual nations maintain a sense of urgency in addressing the climate crisis and make decisions based on robust scientific evidence.

"To uphold the ratchet mechanism outlined in the Paris Agreement, it is essential to have frequent scientific updates on emissions, concentrations, and temperatures. This enables international climate negotiations to stay current and provides the opportunity to adjust and, if required, rectify national policies in line with the evolving climate situation," stressed Professor Maisa Rojas Corradi.

“In the case of Chile, we have a climate change law that aims at aligning government-wide policies with climate action.” 

Remaining carbon budget  

One significant discovery from the analysis is the rapid depletion rate of the remaining carbon budget, which represents an estimate of the amount of carbon that can be emitted into the atmosphere while still maintaining a 50% probability of limiting global temperature rise to within 1.5°C.

In 2020, the IPCC estimated that the remaining carbon budget was approximately 500 gigatonnes of carbon dioxide. However, as of the beginning of 2023, that figure has been reduced by half to approximately 250 gigatonnes of carbon dioxide. This indicates a significant decrease in the allowable emissions to stay within the desired temperature limit.

The reduction in the estimated remaining carbon budget can be attributed to two factors. Firstly, it is influenced by ongoing emissions that have occurred since 2020. Secondly, updated assessments of human-induced warming have played a role in refining the estimates of the remaining carbon budget. These combined factors have contributed to the decreased figure for the allowable carbon emissions.

Professor Forster highlights the pressing nature of the situation, stating, "Even though we have not yet reached 1.5°C of warming, it is highly probable that the carbon budget will be depleted within a few years. This is due to a triple impact of heating caused by substantially elevated CO2 emissions, increases in other greenhouse gas emissions, and the reduction of pollution." The convergence of these factors intensifies the urgency to address climate change promptly.

“If we don’t want to see the 1.5°C goal disappearing in our rearview mirror, the world must work much harder and urgently at bringing emissions down. 

“Our aim is for this project to help the key players urgently make that important work happen with up-to-date and timely data at their fingertips.”   

Dr. Valérie Masson-Delmotte, co-chair of Working Group 1 of the IPCC's Sixth Assessment report and a participant in the climate indicators project, emphasized the significance of the comprehensive update. She stated, "This robust update demonstrates the escalating warming of our climate resulting from human activities. It serves as a timely wake-up call for the global stocktake of the Paris Agreement in 2023, underscoring that the current pace and extent of climate action are inadequate for curbing the escalation of climate-related risks." The statement highlights the urgent need for more ambitious measures to address the challenges of climate change.

As evidenced by recent IPCC reports, it is irrefutable that with each incremental rise in global temperatures, the frequency and intensity of climate extremes intensify. This includes an increase in occurrences of hot extremes, heavy rainfall, and agricultural droughts. The scientific consensus highlights the direct relationship between global warming and the heightened risk and severity of these climate-related phenomena.

The Indicators of Global Climate Change platform (https://igcc.earth/) will provide regular updates on key aspects such as greenhouse gas emissions, human-induced global warming, and the remaining carbon budget. With annual updates, the platform aims to deliver current and relevant information to enhance understanding and decision-making related to climate change.

The website builds upon the success of the Climate Change Tracker, a climate dashboard that effectively presents complex information to the public. Developed by software experts who drew inspiration from the finance industry's approach to presenting intricate data, the Climate Change Tracker serves as a valuable tool in communicating climate-related information to a broader audience. The Indicators of Global Climate Change website incorporates and expands upon the features of this successful climate dashboard.

What the analysis revealed 

The paper titled "Indicators of Global Climate Change 2022: Annual update of large-scale indicators of the state of the climate system and the human influence" presents headline results comparing the "AR6" period (around 2019) with the current state in 2022. The decadal average greenhouse gas emissions for the AR6 period (2010-2019) have been re-evaluated and provided in the assessment.