📢 Climate change cannot be communicated on its own, as decades of awareness-raising and public engagement initiatives have shown. There is growing evidence from the social sciences on climate change communication, which provide many explanations for why engaging with the topic can be challenging. Climate science is fraught with uncertainty, a familiar challenge when communicating with the unfamiliar. For some, the topic may be abstract and intangible. For others, the abstract statistics that define climate discourse may seem remote from their everyday experiences. In some countries, the topic is politically polarized.

However, the same social science literature that documents the challenges of public engagement on climate change also provides reliable guidelines on how to communicate more effectively. It is well known that our worldview, values, and social norms dictate how we receive information and apply it to our own lives. It has also long been recognized that the messenger is at least as important, if not more so, than the message itself. Scientists are trusted by society, and there are many opportunities for public engagement at key moments in the climate calendar, such as the release of IPCC reports.

It is with the aim of providing guidance to IPCC scientists on how to engage the public in the most effective, efficient and evidence-based way possible at these crucial moments that this handbook has been developed. It was commissioned by the Technical Support Unit of Working Group I of the Intergovernmental Panel on Climate Change (IPCC) and produced by Climate Outreach, Europe’s leading specialist in climate change communication. The aim was to distill only the most basic principles of effective communication and engagement.

Social science tells us that it is possible to communicate climate science in a way that makes the message easier for non-scientific audiences to understand and more relevant to their lives and experiences. Connecting with audiences based on shared values builds trust between communicator and audience. While there are no “magic words” that will resonate universally, there are better and worse ways to start a conversation about climate change.

The manual presents six key principles for IPCC authorswhich they can use in public engagement:

1. Be a confident communicator: Scientists are generally highly trustworthy. By using an authentic voice, you can communicate effectively with any audience. In addition to expertise, trust is also determined by the extent to which the communicator speaks authentically, drawing on their own experiences and perspectives. IPCC authors have a variety of specializations, but the public audience will often not limit their questions to one particular area. It is important to distinguish between when you are speaking on behalf of the IPCC and when you are speaking as an expert in your own right. The IPCC reports are scientifically balanced and politically neutral, so it is important to refrain from expressing personal views on climate policy or opinions that go beyond the scope of the IPCC reports if you are speaking as an IPCC scientist. However, as long as you are clear about the capacity in which you are speaking, this should not limit your engagement with the public.
2. Talk about the real world, not abstract ideas.: Although they define scientific and policy discourse, the “big numbers” of climate change (global average temperature targets and atmospheric carbon dioxide concentrations) do not relate to people’s everyday experiences. Focusing on abstract, global metrics like temperature can provoke an unintended response—in some parts of the world, a two-degree warming is welcome if it means less cold winters. Using global numbers or long-term trends can reinforce the perception that the problem is an abstract technical matter that has little to do with people’s everyday lives. This makes it easier for audiences to engage in what is called “psychological distancing,” dismissing climate change as a problem that only concerns the distant future for people living far away. To avoid this, it’s important to use language that positions your science in a way that is relevant to your audience (known as “framing”). All information is “framed” in some way—framing simply means using language to express an idea in a certain way or in a certain light. Start your climate conversation on common ground, using clear language and examples that your audience is likely to be familiar with. Examples of effective frames include avoiding wastethat resonates with all audiences, especially conservative ones, or health benefits cleaner air, which met with a positive response across a wide spectrum of the public. Balance is another frame that speaks to the core values of center-right audiences. Metaphors and analogies are types of framing that help us understand the unknown through familiar terms. They can serve as mental shortcuts and make climate science messages more inclusive and relevant. Examples include the metaphor "loaded cubes" to illustrate the increased likelihood of extreme weather events, "heat-trapping blanket" for the greenhouse effect, or "bath", which is filled with carbon dioxide, to explain the accumulation of emissions.
3. Connect with what matters to your audience: Research consistently shows that people’s values and political beliefs have a greater influence on their attitudes towards climate change than their level of scientific knowledge. People “filter” information based on whether it aligns with their values. When communicating and engaging, connection to widely shared public values or points of “local interest” increases the likelihood that your science will be heard. The facts and figures of the science message should, wherever possible, be based on a platform of shared values – in other words, try to find common ground with your audience. Examples of key values that support the perception of change in the UK energy system include reducing waste, protecting the environment, secure and affordable energy, maintaining autonomy and a fair system. In addition to values, it is also important to connect with local points of interest. This means knowing something about what your audience is likely to care about and using that as a platform to present facts and statistics, rather than starting with the science and then explaining its relevance. Practical tips include researching the location you’re speaking to, partnering with a local group, speaking to interest groups (farmers, gardeners, sports clubs, faith groups) about things that directly affect them, and asking your audience what they love and what is being affected by climate change. You can also share one thing you care about and the risk climate change poses to it.
4. Tell a human story: Most people understand the world through anecdotes and stories, not statistics and graphs. Focusing on narrative structure and showing the human face behind science Telling a compelling story when presenting information will help you. The IPCC has historically been perceived as a dry and inaccessible organization, partly because of the absence of “human faces” behind the science. Scientists’ personal stories – who they are, why they do their work, what inspires and motivates them, what they care about and what they fear – are an incredibly valuable resource. Communicating science in narrative form is more effective when those narratives use language that reflects the interests of the audience. In the context of climate change communication, this means describe the problem, outline its consequences, and talk about solutions. Including solutions is key because without a clear indication of how people can respond to the risks, climate change can seem overwhelming. A simple but effective way to engage your audience in your story is to use a template ABT (And, But, Therefore – A, Ale, Preto), which introduces a “conflict” and a “resolution” to the story. The “And” part is the exposition, the “But” brings in the conflict, and the “Therefore” provides the resolution.
5. Lead with what you know.: Uncertainty is a characteristic of climate science that should not be ignored, but it can be a major stumbling block when talking to the uninitiated. The general level of scientific literacy among the public is relatively low, and science is often perceived in a binary way – as a set of facts, not as a method of understanding the world with uncertainties. For the purposes of public engagement, the focus should be on a narrative approach, not on detailed quantitative analysis of uncertainty. A simple approach to ensuring that uncertainty does not derail a compelling story is to focus on what is known, before discussing uncertainties. Uncertainty in science is often misinterpreted by the public as ignorance. It is well established that in many countries around the world, people dramatically overestimate the uncertainty associated with climate science and underestimate the level of scientific consensus. Mention of level of consensus on the basic fact that humans are responsible for climate change, can be a useful communication tool. Acceptance of scientific consensus has been described as the “gateway to belief” on which other climate-related beliefs are based. The relationship between weather and climate is a key example of effective communication about uncertainty. Extreme weather events can provide tangible evidence of climate change and offer an opportunity to discuss climate risks. Science is increasingly able to quantify the link between some extreme weather events and climate change – communicating growing confidence in "matching" is important. The public is increasingly understanding the connections. Talk about the connection between weather and climate, ideally before (not during or after) an extreme event. Experiences of extreme weather do not override cultural and ideological filters. Stick to the science and avoid overly technical language.
6. Use the most effective visual communication: The choice of images and graphs is just as important and should be evidence-based as verbal and written communication. The “visual language” of climate change is particularly important. The narrow visual vocabulary that currently frames climate change in the public mind (polar bears, melting glaciers, smokestacks, protesters) can undermine the effectiveness of outreach. The Climate Visuals project has conducted research and developed a set of principles for more effective communication, as well as a library of evidence-based images. Five key principles for IPCC authors include: show "real people", not staged photos; tell new stories using lesser-known images; to show the emotional power of climate impacts, by linking impact images to concrete “action” for people; show local climate impacts, especially when they involve individuals with recognizable emotions; and understand your audience, with images depicting “solutions” evoking positive emotions across the political spectrum. In data visualization, which is an integral part of the IPCC’s work but can be challenging for non-experts, it is important to apply principles that ensure clarity and accessibility. These principles are summarized in the acronym MADE: consider your Message (Message), Audience (Audience), Design (Design) of the visual and its Evaluation (Evaluation). Identify the main message, assess the audience's prior knowledge, use familiar visual formats, and test designs on the target audience.

This handbook provides IPCC authors with a resource for their public engagement and communication activities, capturing key findings from the social science literature and relating them to practical examples and situations. It provides a tool for IPCC scientists to feel confident in public engagement in the best possible way, based on the best available evidence. Spring

Glossary of key terms

• Climate Outreach: One of Europe's leading climate change communication specialists, bridging the gap between research and practice.
• IPCC (Intergovernmental Panel on Climate Change): The International Panel on Climate Change Science Assessment. This guide was created for its authors.
• Working Group I TSU (Technical Support Unit): The Technical Support Unit of IPCC Working Group I, which commissioned the development of this guide.
• The social science of climate change communication: A scientific field that studies how people understand and respond to information about climate change, with the aim of providing guidance for effective communication.
• Psychological distance: A phenomenon in which people perceive climate change as a problem that only concerns a distant place or the distant future, making it more difficult for them to engage with it on a personal level.
• Framing: The use of language to convey an idea in a certain way, or in a certain light, in order to make it accessible and increase its relevance to an audience.
• Metaphors and Analogies: Figures of speech that describe unfamiliar things through more familiar objects and language, serving as mental shortcuts for understanding complex information.
• Values: Guiding principles in people's lives (e.g., safety, equality) that significantly influence how they perceive and respond to information, including that about climate change.
• Narrative structure: Presenting information in the form of a story (with exposition, conflict, and resolution), which is a more natural and memorable way for most people to process information.
• ABT (And, But, Therefore) template: A simple framework for structuring a message into a narrative format that includes conflict and resolution.
• Uncertainty (in science): A property of scientific knowledge that recognizes that not all questions have definitive answers and that there are ranges of possible outcomes. Communicating uncertainty is a challenge when communicating with non-scientists.
• Scientific consensus: Broad agreement among scientists in a particular field. In the context of climate change, there is often talk of a scientific consensus that humans are responsible for the changing global climate.
• Gateway to faith: The concept that acceptance of the scientific consensus on climate change can lead to further climate-related beliefs and support action.
• Attribution (weather extremes): The ability of scientists to quantify the extent to which climate change has affected the likelihood or intensity of specific extreme weather events.
• Climate Visuals: A project that explored public perceptions of climate imagery and developed a set of principles and an image library for selecting effective climate-related visuals.
• MADE (Message, Audience, Design, Evaluation): An acronym summarizing key principles for ensuring the clarity and accessibility of data visuals when communicating about climate change.