The SYR aims to synthesize knowledge across the entire IPCC Sixth Assessment report (AR6), which is a cycle spanning over seven years and consisting of three Special reports and three Working Group (WG) reports. Each IPCC assessment cycle includes WG reports and a few Special reports, the topics for which are chosen based on the proposals from members of the IPCC Panel representing different countries and observer organisations.

The SYR synthesizes results from the six underlying IPCC reports, offering the most authoritative yet concise assessment of the state of knowledge on the science of, and response to, climate change. It provides stakeholders (e.g., policymakers, private sector, NGOs, civil society) and the public with a broad overview of climate science and policy. While the information itself isn’t new, emphasis on different issues can change, specific perspectives can be highlighted, and linkages across all six reports can only be analysed and synthesized after their completion at the end of the assessment cycle. Given that these reports comprise thousands of pages and individual references, synthesizing them is considered a crucial final step in the assessment cycle.

Although it is difficult to easily summarize, a few points stand out:

• The 1.5°C target: Global warming of 1.1°C has resulted from many decades of fossil fuel use, unsustainable land use and other sources of greenhouse gas emissions; limiting warming to 1.5°C will require rapid, deep and sustained emissions reductions across all sectors.
• Policy and implementation: With current policies, 3.2°C of global warming (median value) is projected (medium confidence) by 2100. To avoid the risks of climate change, near-term action is needed to strengthen the implementation of existing policies and raise the ambition for future climate actions.
• Impacts, vulnerability and adaptation: Nearly half of the world’s population lives in climate-vulnerable regions, with climate impacts already being observed. Progress has often been incremental or fragmented; therefore, it is crucial to direct investment in climate adaptation measures towards the most vulnerable groups and regions.
• Climate finance: The goal of mobilizing USD 100 billion per year to support climate action in developing countries remains unmet. Public and private finance flows for fossil fuels currently exceed those for climate mitigation and adaptation. Moreover, tracked finance flows for mitigation are significantly higher than those for adaptation.
• Solutions availability: Effective mitigation and adaptation solutions exist across many sectors and systems, including more affordable renewable energy, greener urban planning with climate benefits, healthier diets, improved land-use management systems and tools for monitoring and analysing progress.
• Multi-level cooperation and governance: Enhancing international cooperation and strengthening governance and institutions is vital to climate-resilient development. Accelerated climate action in mitigation and adaptation can be achieved through finance, technology, capacity building and especially the support of technology transfer for developing countries. Incorporating diverse knowledge and practices, including Indigenous, local and scientific knowledge can facilitate climate-resilient development.

The three special reports focus on areas that were deemed critical during the AR6, providing an evidence base that complements that of the three Working Group reports by addressing certain issues in greater detail. The 1.5°C report evaluated the differences between pathways to maintaining global average temperature increase below 1.5°C and those below 2°C, in the broader context of sustainable development and the global response to climate change. The Land report examined land use and climate linkages, emphasizing areas facing land degradation, desertification, and the impacts on agriculture and food production, while exploring land-based mitigation and carbon removal. The Oceans and Cryosphere report explored how these systems are affected by climate change, including sea level rise and glacier melt, and the possible responses.

The SYR offers scientific and science-to-policy guidance for COP28 work programmes and agenda items. It complements the Global Stocktake, which evaluates progress in meeting the Paris Agreement goals. Since the SYR is being launched nearly nine months before COP28, it has a good opportunity to influence the COP, as agenda items are usually established at the UNFCCC Bonn Intersessional meeting in June.

The SYR identifies key issues and priorities at the global level, so its scope for addressing specific national or regional issues is limited. It does not provide guidance for specific countries, and unlike the WG II report, it does not have separate sections by world region. However, in cases where there are significant regional differences, the report highlights them.