Diplomatic Standoff at IPCC Addis Ababa Session Threatens to Delay 2028 Climate Assessment

Several member states argue that delaying the next major global climate assessment until 2029 will ensure better participation from researchers in developing nations. However, climate scientists and allied governments warn that pushing the publication past 2028 will force the next United Nations global stocktake to rely on outdated data. The dispute has paralyzed the world's leading climate science body.[1][3]

The Intergovernmental Panel on Climate Change (IPCC) opened its 65th plenary session in Addis Ababa, Ethiopia, on October 12. The 195 member countries are attempting to finalize the timeline for the Seventh Assessment Report, known as AR7. The panel has remained deadlocked over this schedule for nearly three years, making this meeting critical.[1][4]

The AR7 cycle will produce three foundational reports. Working Group I covers the physical science of climate change, while Working Group II assesses vulnerability, impacts, and adaptation. Working Group III evaluates options to curb warming and reduce greenhouse gas emissions across the global economy.[1][2]

The scientists leading these groups have proposed completing all three documents by September 2028. This timeline is specifically designed to inform the second global stocktake under the Paris Agreement. That mandatory five-yearly review process concludes at COP33 in November 2028 and will dictate the next round of national emissions targets.[2]

The 2028 Deadline

A coalition including India, China, Saudi Arabia, Russia, and Kenya is pressing to postpone the Working Group II and III reports into 2029. These nations argue that the accelerated 2028 schedule places an undue burden on scientists from poorer countries, who often lack institutional support.[1][5]

They maintain that researchers need sufficient time to conduct new studies, publish findings, and navigate the extensive IPCC review process. Rushing the timeline, they argue, would compromise the quality of the data and limit the geographic diversity of the contributing authors.[5]

Kenyan delegate Joyce Kimutai noted that a rushed process would inherently exclude voices from the Global South. "If you have a process that goes very quickly, it would not be inclusive," Kimutai said, highlighting the structural barriers developing nations face.

Many researchers in developing economies struggle to secure unpaid leave or funding to participate in the demanding, multi-year assessment cycles required by the UN body. About half of the lead authors and editors chosen for AR7 come from developing or transition economies, according to the IPCC.[4]

Their full participation is central to the report's legitimacy. The next assessments will be the first to include dedicated chapters on climate finance and irreversible harm. These issues are top priorities for nations facing immediate climate impacts and seeking compensation for loss and damage.

Conversely, a coalition led by European, Latin American, and small island states insists that the 2028 deadline is non-negotiable. They argue that the delay is a political maneuver designed to weaken the pressure for stronger climate action and financial commitments from the developed world.[1][3]

Risks of Outdated Science

If the AR7 reports are not ready for the 2028 stocktake, negotiators will be forced to base their decisions on older science. The Sixth Assessment Report relies on scientific literature published before 2022. The global climate situation has shifted significantly since that cycle concluded.[5]

In 2024, the global average temperature exceeded 1.5 degrees Celsius above pre-industrial levels for the first time on an annual basis. This milestone accelerated the timeline for projected impacts and altered the baseline for future warming scenarios. Relying on older data means the 2028 negotiations might not accurately reflect these emerging risks.[5]

Climate Analytics has warned that failing to align the AR7 reports with the stocktake could marginalize the IPCC within the formal UN process. This would leave a vacuum for inputs that are not grounded in rigorous, globally negotiated consensus assessments, weakening the foundation of future treaties.

Slovak climatologist Jozef Pecho emphasized the danger of proceeding without a unified scientific baseline. Pecho told Reuters that the room for cherry-picking and distorting climate science during negotiations would expand significantly without an updated assessment to anchor the discussions.[1]

The IPCC's authority depends entirely on providing a single, undisputed factual foundation that all 195 member nations have formally approved. The deadlock in Addis Ababa comes at a time of broader institutional strain for the organization, complicating its ability to deliver on its mandate.[1]

The United States, historically the panel's largest financial contributor, withdrew from the organization in January 2026. This unprecedented five-meeting impasse over scheduling has raised concerns about the body's ability to function effectively amid growing geopolitical polarization and funding shortfalls.

Navigating the Plenary

The Addis Ababa session, hosted by the United Nations Economic Commission for Africa, will also address the mechanics of future assessments. The panel's provisional agenda includes a comprehensive review of the IPCC's principles and procedures to ensure they remain fit for purpose.[4]

Delegates will examine how to integrate emerging technologies into their workflow. This includes reviewing a specific document on the role of artificial intelligence in scientific assessment and data synthesis, bringing questions about emerging technology directly into the governance of international science.

The disagreement reaches into the foundations of science diplomacy. The IPCC does not conduct original research; instead, it brings scientists together to assess existing knowledge. Governments then participate line-by-line in the formal approval of major findings, ensuring political buy-in.

Its authority depends on both the scientific credibility of its assessments and the perceived legitimacy of the international process behind them. By October 16, governments must either agree on a firm publication date or push the decision to a future meeting.

A failure to resolve the timeline this week increases the likelihood that the 2028 UN climate talks will proceed without a comprehensive, updated scientific foundation. The panel's authors can only be as useful as the calendar allows, leaving the timeline in the hands of the governments the science is meant to inform.