The Intergovernmental Panel on Climate Change (IPCC) prepares comprehensive Assessment Reports every six years on the state of scientific, technical and socioeconomic knowledge on climate change, its impacts and future risks, and options for reducing the rate at which it is taking place. Each IPCC Report includes inputs from hundreds of scientists around the world and provides a scientific consensus on climate science. But the Earth system is dynamic, a lot can change in the six years between IPCC Reports, so it is important to release up-to-date scientific information on the state of the climate with greater frequency. Such updates complement the IPCC Reports and are crucial for decision-makers and policymaking processes, particularly at the annual Conference of the Parties (COP) of the United Nations Framework Convention on Climate Change.
United in Science
WMO compiles the annual United in Science report to provide an overview of the most recent climate science-related updates from key global partner organizations. United in Science makes scientific information more accessible to a broad audience by including concise summaries and key messages that are easy to understand.
The 2022 edition included an overview of global atmospheric greenhouse gas concentrations, emissions and budgets from the WMO Global Atmosphere Watch, the Global Carbon Project and UN Environment Programme. Data on global warming and impacts were taken from the annual WMO State of the Global Climate report and climate predictions for the years ahead were provided by the Met Office (United Kingdom). In addition, the report included sections on Climate Change and Cities, Tipping Points in the Climate System, Extreme Weather Events and Socioeconomic Impacts and Early Warning Systems for Adaptation and Disaster Risk Reduction. The report also highlighted key messages from the IPCC. The United Nations Secretary-General uses United in Science to provide unified climate information and promote ambitious climate action.
The 2023 edition of United in Science will focus on weather, water and climate science for sustainable development and will be launched ahead of the UN Sustainable Development Goals (SDG) Summit in September. The report will include contributions from key global partner organizations, summarizing the latest state of the climate and highlighting how weather, water and climate science supports relevant SDGs.
The State of the Climate
The WMO global State of the Climate reports have been produced annually since 1993. The reports provide an authoritative, scientific voice on the changing climate and the impacts that are felt on the ground. In 2019, WMO began issuing regional State of the Climate reports, which now cover all six WMO regions: I-Africa, II-Asia, III-South America, IV-North America, Central America and the Caribbean, V-South-West Pacific and VI-Europe.
The annual snapshot of the current state of the climate in the reports do not focus on predictions or specific sectors, nor do they prescribe policy.
Each is a 40–50-page comprehensive climate data overview for the year in language that is accessible for public audience. Many of the contributing experts and reviewers of the State of the Climate reports are lead authors or key contributors to various IPCC reports. The State of the Climate reports provide concrete examples of accurate predictions from the IPCC and the strong synergies between the two organizations ensure consistency between the various reports and create more platforms to amplify messages.
|Global annual mean temperature difference from pre-industrial conditions for 6 global temperature data sets (1850–2021). Source: UK Met Office|
All the State of the Climate reports follow a similar structure, focusing first on headline climate indicators, including surface temperature, greenhouse gas emissions, ocean heat content, ocean acidification, sea-ice extent, and glacial mass balance1, situating them within larger climate drivers and variability. For example, the recent State of the Global Climate 2022 reported the year as the fifth or sixth warmest on record despite La Niña, which brings cooler conditions. The scientific rigor behind the measurement of the indicators and careful review process of the reports helps ensure that the messages are trustworthy.
The reports also highlight the high impact events reported by WMO Members throughout the year as well as impacts on specific sectors – food security, health, population displacement and migration – through contributions from various UN agencies. This helps policymakers to understand the connection between the various ways in which the climate is changing and the impacts that are felt on the ground. For example, the State of the Climate in Asia 2020 highlighted damages associated with climate related hazards in the region, specifically highlighting countries where damages exceeded 0.5% of Gross Domestic Product (GDP) such as Bangladesh, India, the Islamic Republic of Iran and Pakistan.
The conclusion of each report focuses on pathways for climate change adaptation for policymakers such as by improving the coverage of Early Warning Systems, by developing better National Adaptation Plans and by connecting climate to achieving the Sustainable Development Goals (SDGs)2. While avoiding policy prescription, this section helps leaders to understand effective action that can be taken to address some of the worst impacts climate change.
Over the years, the reach of the reports has increased significantly both globally and regionally. Today, the State of the Climate reports are read by the scientific, policy and academic communities and picked up by major media outlets. The reports are one of the most anticipated products of the year from WMO. Key messages regarding headline climate indicators or extreme events often attract worldwide mass media attention, amplifying the Organization’s outreach to local, regional and international audiences. For example, the mention of the possibility of complete deglaciation in Africa by 2030 in the State of the Climate in Africa 2020 was covered by CNN, BBC, Forbes and Al Jazeera.
By reporting on the best available climate science, informing on extreme events and impacts, and pointing to key climate policy, the State of the Climate reports have become an indispensable source of information for shaping climate policy and decision-making at the regional and global scale. The Provisional Global State of the Climate report is launched each year at the annual session of the Conference of Parties (COP) to the United Nation Framework Convention on Climate Change (UNFCCC), where world leaders convene to receive the most up-to-date climate information. Regional reports are often promulgated at high-level ministerial or regional events to amplify messaging and the call for action on climate change.
In the last few years, the reports have been complemented by interactive digital StoryMaps, which help to contextualize the content by providing background videos and photos and include quizzes to engage public interest and reinforce learning.
|Headline State of the Climate indicators and their connection to the risks posed to achieving select Sustainable Development Goals (SDGs). Source: WMO|
State of Climate Services
WMO has issued annual reports on the State of Climate Services since 2019 in response to a request from the UN for more information on climate adaptation needs. The information provided in the reports help countries, funding agencies and development partners to assess gaps in the climate services value chain and to define steps to address them, thus leading to more effective adaptation investments. In turn, improved climate adaptation measures positively impact development outcomes at country levels. The State of Climate Services reports focus on the sectors identified in the Nationally Determined Contributions (NDCSs) of the Parties to the Paris Agreement of the United Nations Framework Convention on Climate Change (UNFCCC) – such as agriculture, water, disaster risk reduction, energy and health.
1 Trewin B, Cazenave A, Howell S, Huss M, Isensee K, Palmer MD et al (2021) Headline indicators for global climate monitoring. Bull Am Meteor Soc 102(1):E20–E37