Researchers at the University of Graz enable reliable monitoring of Paris climate goals

New data from the University of Graz shows a six per cent greater increase in global surface air temperature than indicated by current monitoring. In order to meet the Paris climate goals, emissions must be drastically reduced. Photo: Frank H. - stock.adobe.com

Global warming is continuously advancing. How quickly this will happen can now be predicted more accurately than ever before, thanks to a method developed by climate researcher Gottfried Kirchengast and his team at the University of Graz. For the first time, this method enables reliable monitoring of the Paris climate goals and shows that temperatures are rising faster than expected in the latest IPCC report. The new findings have just been published in the scientific journal Communications Earth & Environment.

In the Paris Agreement of 2015, the international community of countries agreed to limit global warming to well below 2 °C, and preferably to 1.5 °C, compared to pre-industrial levels. This refers to the increase in global surface air temperature, inspected at any time of interest as an average over 20 years. The latest IPCC report expected the 1.5 °C threshold to be reached between 2030 and 2035. Climate researcher Gottfried Kirchengast from the Wegener Center and Institute of Physics at the University of Graz now has to revise this estimate: “Our new results show that we will exceed this limit as early as 2028 – with a standard deviation range of plus/minus two years. The benchmark record we have developed shows the global temperature rise with unprecedented reliability and therefore allows us for the first time to also propose an assessment scale to verify whether the Paris climate goals are being met or missed,” the scientist points out.

Reference standard for global warming
Over the oceans, conventional monitoring of global warming does not use the air temperature above the water surface, but rather the temperature of the top few meters of seawater, such as recorded directly by drifting buoys. This results in an uncertainty that could not be properly corrected so far. The researchers at the University of Graz have now succeeded in doing so. Based on the best available data sources from international climate centers, they computed a new benchmark record for the period from 1850 to 2024, complemented by predictions up to 2034 and scenarios to 2050. “Our data show a six percent higher increase in global surface air temperature than the conventional monitoring,” says Kirchengast. “And we can distinguish the human-induced temperature increase from specific climate phenomena like El Niño and other natural fluctuations, and predict the annual mean temperature of any current year, such as now for 2025, as early as from August,” adds the co-author of the publication, Moritz Pichler from the Wegener Center.

Compliance assessment for the Paris Agreement
Building on the reliable monitoring of global warming, the researchers propose a four-classes assessment scale to quantitatively gauge to what degree the Paris climate goals are being met or missed. “This creates a completely new compliance assessment basis for the political and legal implementation of the agreement,” explains Kirchengast. He suggests further standardization in the context of the World Meteorological Organization and the IPCC, to provide it as an official assessment method for the Paris Agreement member countries. “It is important to provide clarity for the Paris climate goals so that policymakers and all of us know where we actually stand and what it needs to meet them,” emphasizes the researcher, proposing as a complement to the 1.5° C goal that the imprecise wording ‘well below 2 °C’ be firmly defined as ‘below 1.7 °C’. “It is high time to make these internationally binding targets for limiting global warming truly measurable and verifiable in order to underpin the urgently needed climate action by a generally valid climate-physics foundation,” concludes Kirchengast.

Publication:
Gottfried Kirchengast & Moritz Pichler (2025): A traceable global warming record and clarity for the 1.5 °C and well-below-2 °C goals. Communications Earth & Environment, 2 June 2025, DOI: 10.1038/s43247-025-02368-0
https://www.nature.com/articles/s43247-025-02368-0

The research is part of the Field of Excellence Climate Change Graz at the University of Graz.

The new reference data set and other key data on climate change are freely accessible and available worldwide via the Graz Climate Change Indicators – ClimateTracer web portal.

The graphic illustrates the rise in global surface air temperature. ©University of Graz / Wegener Center

The graphic illustrates the observed and predicted rise in global surface air temperature until 2024 and 2034, respectively, followed by two different scenarios up to 2050. The blue line depicts the IPCC's ambitious climate action scenario that is compliant with the Paris goals: strong emission reductions towards net-zero CO2 emissions around the middle of the century. The orange line shows the rise in temperature if continuing the current annual emission levels without reduction, which leads to a severe exceedance of the goals up to beyond 2 °C. © University of Graz/Wegener Center

Gudrun Pichler

Related news

Like an open book: researchers invite people to share their experiences digitally

PhD student Saumya Sadhu has launched the "Human Chapters" initiative to bring people together at online events on the topic of diversity at universities. Interested parties can ‘look up’ certain chapters like in a book by exchanging ideas directly with like-minded people in digital spaces.

30 years after Srebrenica: Heike Karge supports forces for reconciliation

This year marks the thirtieth anniversary of the Srebrenica massacre in Bosnia. To this day, Serbia and the Republika Srpska refuse to characterise the killing of more than 8,000 Bosnian Muslims as genocide. Those in power lack the will to come to terms with the atrocities. There is hope from strong forces in civil society who want to make a process of reconciliation possible by documenting war crimes across national and ethnic boundaries. Heike Karge, Professor of Southeast European History at the University of Graz, supports them in joint research projects, among other things.

Styrian Economic Chamber awards scholarships to three students at the University of Graz

In their Master's theses, Daniela Pinter, Elena Pusca and Leonie Sayer are focussing on topics that are of particular importance to the economy. On 1 July 2025, the students from the University of Graz each received a research grant of 2,100 euros from the Styrian Economic Chamber. In addition, 500 euros each will go to the institutes where the theses are supervised.

Signals from the roots: how the plant hormone cytokinin influences flowering

Many do it in spring, others wait a little longer and some really get going in winter – when a plant begins to flower is controlled by various internal and external signals. In a study published in the renowned scientific journal Plant Physiology, researchers at the University of Graz were able to clarify the role played by the hormone cytokinin in this process. The findings are also interesting with regard to the breeding of crops for agriculture. In view of changing climatic conditions, adjustments to the start of flowering could help to secure yields.