From Persuasion Theory to Climate Action: Insights and Future Directions for Increasing Climate-Friendly Behavior

Abstract

Combatting climate change requires motivating individuals to adopt climate-friendly behaviors, whether to make individual lifestyle changes, vote for environmental policy, or accept technological innovations. Efforts to promote such behaviors can be more effective when informed by theoretically and empirically driven insights into human behavior change—an endeavor led by persuasion research. This review explores the intersection of persuasion research and climate-friendly behavior, demonstrating how persuasion theory can be applied to encourage climate action. Key theoretical approaches are examined, including the theory of planned behavior, social norms, narrative-based persuasion, framing, and emotional appeals, along with considerations for their practical applications. Additionally, promising future directions for integrating persuasion research into climate change interventions are highlighted; these include tailoring messages based on moral foundations theory and the transtheoretical model, as well as leveraging artificial intelligence to personalize climate-friendly recommendations. By synthesizing insights across persuasion and environmental research, this review provides valuable guidance for environmental researchers, policymakers, intervention designers, communication strategists, and environmental activists in developing robust and effective strategies to increase climate action at a time when accelerating these behaviors is more urgent than ever.

1. Introduction

As greenhouse gas (GHG) emissions continue to accumulate beyond safe and sustainable levels, there is increasing recognition that mitigating climate change requires human intervention [1,2]. Climate change is unequivocally caused by human action, and while scientists widely agree that existing technologies can effectively ameliorate environmental crises, they also note that the lack of public and political will makes it unlikely that behavior will shift in time [3,4]. Therefore, addressing climate change involves increasing climate-friendly behavior specifically, and pro-environmental behavior (PEB), or behavior that limits harm to the environment and/or benefits the environment, in general [5,6,7].

Although each individual contributes relatively little to global GHG emissions, their cumulative contributions play a substantial role. Collectively, household consumption accounts for more than 60% of global GHG emissions, along with 50–80% of total land, water, and material use [8,9]. Additionally, the European Environment Agency reported that while it was on track to meet 2030 targets in several areas related to policy and technological advances, it was off track to meet targets related to citizens’ consumption and use of alternative transportation [10]. The large cumulative contribution of individual actions indicates that behavior change is a necessary component of climate change mitigation. In fact, Dietz et al. [11] estimated that 20% of United States (U.S.) emissions could be reduced by consumer behavior change alone, a proportion that they proposed would increase with advancements in green technology (see also [12,13,14]). Because global political leaders have recently stepped back environmental protections, it is more important than ever to promote climate action at individual, organizational, national, and global levels. While individual behaviors are certainly not the only, nor the easiest, focus of climate change mitigation efforts, their reduction is necessary to combat the warming planet [5,15].

Choosing climate-friendly over alternative behaviors requires individuals to surmount a multitude of psychological, social, and structural barriers that regularly interfere with substantive climate action [15,16,17,18]. First, on the scale of human lifespans, climate change is a slow process that is difficult to experience directly [17,19]. The temporal, spatial, social, and hypothetical distribution of environmental threats contributes to the perception that climate change is psychologically distant, which reduces the sense of urgency to engage in climate-friendly behaviors [20] (but see [21] for arguments that this effect is overestimated). Furthermore, while PEBs such as shopping locally or taking alternative modes of transportation often pose immediate personal costs in the forms of time, expense, and/or inconvenience [22,23,24], the collective benefits of PEB are dispersed both geographically and temporally, and are thus rarely enjoyed by the individuals who perform them—and if so, only in the distant future [17,22]. The collective causes and consequences of climate change also reduce the sense of personal responsibility to engage in climate action [25,26,27,28], and increase feelings of apathy and withdrawal, which reduce environmental efforts [29].

The complexities associated with climate change produce cognitive biases that interfere with climate-friendly behavior. For instance, both citizens and policymakers regularly discount distant climate change threats, and rewards for climate action, in favor of the immediate benefits from cheaper, easier, and habitual unsustainable behaviors (discounting bias) [17,19,30]. They also tend to underestimate the probability of unfavorable climate change events (optimism bias), and to focus on, interpret, and remember information that confirms their existing ideas and expectations about climate change consequences (confirmation bias) [17], which both reduce a sense of urgency. Because most people are not yet impacted by climate change on a daily basis, the tendency to evaluate the likelihood and importance of an event based on information most readily available in memory (availability bias) [17,30,31] also interferes with the psychological urgency to act. Many additional cognitive biases complicate climate change behavior; see [17,18,19,32] for reviews.

Given that most individuals are not responsible for the policies, global supply chains, and economic structures that drive polluting practices at individual, organizational, national, and international levels [33], it would be a grievous mistake to imply that everyday individual actions such as reducing food waste should be the focus of climate change interventions while the pollution from industrialization, capitalism, multinational corporations, and digitalization (including the rise of artificial intelligence) can continue unbated [34]. However, human action is also necessary at those higher levels [15]. For example, transitioning to a circular economy depends not only on policy and regulation, but also on psychological and behavioral variables including the environmental attitudes and leadership of company decision-makers, pressures from consumers and competing organizations, the willingness of employees to carry out organizational environmental missions, and consumers’ acceptance of technical solutions [35,36,37,38]. Furthermore, the success of pro-environmental policy is itself dependent upon people willing to promote environmental agendas in office, vote for environmentally aware political leaders, and accept, adopt, and model new regulations [5,39,40]. Too many environmental policies are based on oversimplified and erroneous assumptions of cognitive biases and human behavior, which can detract from the efficacy of climate change interventions [16,19,32,41]. Well-intentioned policies can even have unfavorable impacts on PEB when behavior change science is not considered; for example, policy improvements in energy efficiency can make individuals feel justified in increasing their energy consumption (i.e., rebound effect) [42], and harsh environmental regulations can produce reactance that decreases PEB [33]. To create evidence-based interventions for climate action (whether for policy, campaigns, or grassroots movements), it is therefore necessary to address the barriers to and facilitators of behavior change—an effort led by persuasion research and theory.

2. Persuasion Research for Climate Action

Responding to calls to base pro-environmental interventions on theoretically and empirically driven insights [5,43,44], scholars in the fields of environmental communication and psychology have drawn from various theoretical frameworks of persuasion. Persuasion can be defined as any effort that intends to, or is perceived as having the intention to, shape, reinforce, and/or change the responses of another, in which there exists some measure of freedom [45,46]. Because many efforts to mitigate climate change attempt to reinforce or change behavior toward perceived voluntary practices that reduce environmental impacts, persuasion research is especially suited to advance an understanding of the determinants of climate-friendly behavior. Furthermore, many persuasion theories provide insights into the most effective structural changes to promote desired behaviors [5]. In fact, the fields of environmental communication and persuasion are so intertwined that some scholars working to increase climate-friendly behavior feel that “environmental communication is essentially persuasion; we communicate to make people change their attitudes, intentions, and consequently their behaviour” [15] (p. 57).

This review describes the ways in which persuasion research has effectively been applied to encourage climate-friendly behavior, and the corresponding strengths and limitations that should be considered prior to applying these tools to climate change interventions in practice. After describing prominent persuasion theoretical frameworks in the PEB literature, it considers promising future directions for the intersection of persuasion and climate-friendly behavior change. Whether used at the individual, campaign, organizational, or institutional levels, these persuasion frameworks can help increase climate action at a time when evidence-based practices are urgently needed.

Table 1. Reviewed Theoretical Frameworks from Persuasion and their Main Contributions to Developing Climate Change Interventions.

Persuasion Theoretical Framework		Main Contributions to Developing Climate Change Interventions
Theory of Planned Behavior		The most prevalent theory for understanding environmental behavior Behavior (intention and action) predicted by attitudes, norms, and perceived behavioral control (PBC) Formative research can identify the beliefs underlying attitudes, norms, and PBC to address context-specific barriers to climate action
Social Norms		Often achieve the largest effect sizes in field interventions Formative research can identify the type or combination of norms that will be most effective, limiting counterproductive reactance and boomerang effects
Narratives		Campaigners can communicate climate change information without revealing persuasive intent Especially useful when developing interventions for polarized audiences Can be almost twice as effective as disseminating information through traditional public service announcements
Framing		Emphasis frames can omit polarizing information, and highlight accepted benefits of PEB Equivalence frames (e.g., gain vs. loss) show mixed results, but loss frames can evoke more fear
Emotions	Fear	Four components to fear appeals: severity, susceptibility, response efficacy, and self-efficacy Linear relationship between fear and persuasion, especially when efficacy information included However, evidence in climate change contexts is lacking, and evoking susceptibility may be central
	Pride and Guilt	Can drive PEB when prompted to self-reflect or evaluate one’s environmental behavior Both emotions can function anticipatorily, thus driving PEB prior to negative actions May mediate the effects of social norms appeals on climate-friendly behavior
	Hope	Motivates individuals to pursue their goals, similar to self-efficacy Persuasion depends on what one is hopeful for: Hope for climate action can increase PEB, while hope to avoid the problem is demotivational
Message Tailoring		Different interventions are often needed for different audiences Perceived as more relevant to the audience, which increases subsequent persuasive outcomes
Moral Foundations Theory		Liberals and conservatives apply different sets of moral values to guide attitudes and behaviors Using binding moral frames favored by conservatives can reduce polarized responses
Transtheoretical Model of Behavior Change		Behavior change unfolds over time as a progression through a series of stages Different information is needed as individuals progress through the stages of behavior change
Personalization		Recent evidence suggests personalized climate-friendly recommendations promote favorable environmental attitudes, behavior, and self-perceptions May overcome traditional tradeoffs between reach, effect, and durability of interventions

provides an overview of the persuasion frameworks reviewed in this chapter, highlighting their key contributions to the development of climate change interventions. These theoretical frameworks were selected based on the following criteria: (a) they represent prominent areas within persuasion research and are recognized as effective for understanding and shaping attitudes and behavior in general; (b) they are frequently applied in climate change or other PEB intervention research to develop evidence-based strategies; and (c) they have demonstrated promise in promoting climate-friendly behavior in field-based studies. While this review attempts to cover a wide range of persuasion research that may be useful for promoting climate-friendly behavior, it does not claim to provide an exhaustive list of theoretical frameworks that may effectively be applied in this context. Further, this review emphasizes the importance of formative research in selecting intervention strategies that have the most potential for impact in the intervention context, and thus focuses on the theoretical frameworks that can aid in the selection of specific intervention tactics (e.g., providing rewards or penalties, seeking commitment, giving feedback; see [28,47] for helpful reviews of environmental intervention categories).

2.1. The Theory of Planned Behavior

The theory of planned behavior (TPB) is one of the most widely used persuasion theories for understanding individual behaviors in general, and is the most prevalent theory for understanding environmental behavior [48,49]. The TPB has been used successfully in interventions to increase climate action such as taking alternative transportation [50,51], reducing energy consumption [52], adopting environmental management practices [53], engaging employees in workplace PEB [54,55], and understanding willingness to pay for environmental policies [56], among many others (see [49] for a scoping review of the TPB in environmental interventions). According to the TPB, an individual’s behavior is best predicted by their behavioral intention and their perceived behavioral control (PBC), which is the perceived difficulty or ease of performing a behavior (similar to the concept of self-efficacy) [57,58,59]. In turn, intention to perform the behavior is predicted by people’s attitudes toward the behavior, subjective norms, and PBC [60]. In the context of the TPB, attitudes are defined as the favorable and unfavorable evaluations or appraisals of the identified behavior, and subjective norms are perceived social pressure from important others to (not) perform a behavior [60]. Although the relative importance of each of these antecedents in predicting behavior intention varies across both behaviors and contexts, the PBC and self-efficacy constructs are consistently two of the strongest predictors of PEB (intention or action) across environmental intervention research [58,61,62,63].

Beyond predicting behavior, a central contribution of the TPB is its ability identify behavioral determinants through the antecedents of attitudes, subjective norms, and PBC [49]. According to the TPB, attitudes, subjective norms, and PBC are each determined by the product of the individual’s salient beliefs and a measure of their value: attitudes are determined by the product of behavioral beliefs and the individual’s evaluation of the belief’s attribute; subjective norms are determined by the product of normative beliefs and their motivation to comply; and PBC is determined by the product of control beliefs and power [60]. These equations make it straightforward for scholars to assess the relative importance of each determinant of climate-friendly behavior within a specific population, as well as to interpret and compare the determinants of behaviors in different contexts [5,49].

In climate change interventions, information about the beliefs underlying attitudes, norms, and PBC can help to identify the particular barriers that must be targeted for behavior change in different settings [5,49]. For example, Greaves et al. [55] interviewed employees of a public organization to identify their attitudinal, normative, and control beliefs about climate-friendly workplace practices. From the target audience’s salient beliefs, the authors created valid and reliable measures of attitudes, subjective norms, and PBC to survey a representative sample of employees in the organization [55]. Through this process, Greaves et al. [55] demonstrated that climate-friendly behavior in that organization could be meaningfully increased by accelerating the start-up time of the workplace PCs and simplifying the booking system [55]. Thus, by employing the framework of the TPB, Greaves et al. [55] were able to make specific recommendations to the host organization to facilitate workplace climate action, many of which had already been implemented by the time they published their results.

Because of its facility in identifying behavioral determinants, the TPB is thought to be one of the most effective theories from which to develop behavioral interventions [49]. It is no surprise that the TPB has gained recognition as one of the most effective theories to explain and encourage PEB [64], and as being particularly helpful in predicting behaviors perceived as being difficult or effortful [5,44,62]. However, a scoping review of the TPB within PEB research found that 86% of the identified articles overlooked beliefs when exploring the influence of behavioral antecedents on environmental action [49]. By ignoring this central element in the TPB, researchers “undermine the principal utility of the TPB—identifying beliefs that should be targeted in behavioral interventions” [49] (p. 7). Furthermore, the TPB also specifies that the behavioral antecedents (attitudes, norms, and PBC) must be measured in relation to a specific target behavior [60]. For example, studying recycling behavior through the TPB should involve examining attitudes towards recycling, perception of subjective norms related to recycling, and perceived control over recycling behavior, rather than general attitudes, norms, or PBC. However, many studies of environmental interventions using the TPB instead measure general PEB and/or general antecedents, despite concerns that the TPB “seems unsuitable for exploring non-specific actions” [49] (p. 5), [60]. Still, a recent meta-analysis on recycling behavior found that, although there were stronger relationships between behavior-specific antecedents and recycling, general measures of environmental attitudes, norms, and PBC were also related to this target behavior [58]. Together, these findings suggest that the TPB has great utility in understanding and motivating climate action, but that scholars have yet to take full advantage of its explanatory and predictive power.

Beyond issues related to measurement, the TPB has also been critiqued for being too simple, too cognitive, and for being unable to account for the large intention–behavior gap [49,65,66]. Though some fault the theory for not including unconscious influences on behavior that impede rational reasoning, such as cognitive biases, [67], Ajzen [68] argues that the theory makes no assumptions about whether the beliefs underlying the theoretical constructs are rational or irrational—only that they influence the formation of attitudes, norms, and PBC. However, in understanding climate action, the TPB does overlook other variables, such as emotions [28], personal moral norms [48,65], and other types of social norms [69] that have demonstrated influence over environmental action. For these reasons, many choose to strengthen climate change interventions by extending the TPB with additional theoretical constructs [49].

2.2. Social Norms

Another important line of persuasion research to inform climate change interventions is concerned with the use of social norms. Social norms are defined as standards, or rules, of behavior that are shared among members of a group and which guide and/or constrain behavior without legal force [48]. Social norms encourage people to act according to social standards by providing information about what is socially adaptive and by implying the threat of social sanctions if normative standards are not followed [70,71]. Several cognitive biases contribute to the subtle but powerful effect of social norms [72], including the tendency to adopt the beliefs and behaviors that others have already adopted (bandwagon effect), and the tendency conform to group standards in the way one thinks and behaves (conformity bias) [17]. Social norms are used extensively to enhance the persuasiveness of climate change messaging [28,70,72], and produce some of the largest effect sizes of environmental interventions conducted in the field [6,70].

The literature distinguishes between many different types of social norms (see [71] for an extended taxonomy), such as subjective norms (defined above), implicit and explicit norms, internal and external norms, perceived and actual norms, and prescriptive and proscriptive norms [69], though the most common distinction within environmental behavior research is between injunctive and descriptive norms [69]. The focus theory of normative conduct (FTNC) [73] defines descriptive norms as the behavior that is typical or normal within the salient referent group. Descriptive norms provide individuals with information about the status quo, which motivates them to conform to behaviors that are common within their social circle [28]. In contrast, injunctive norms specify what behavior is morally approved or disapproved by the referent group [73]. Injunctive norms provide information about what should be done, which motivates individuals to align their behavior with the norm in order to avoid social sanctions, or to gain social approval [28]. Although injunctive norms are similar to subjective norms from the TPB, and are sometimes used interchangeably in the literature [74,75], subjective norms can be considered a subset of injunctive norms, which also include personal introjected and personal integrated norms, in order of increasing internalization [71].

Recently, scholars have also explored the potential for dynamic norms to promote PEB. Dynamic norms provide information about changes in norms over time [76,77], which motivate individuals to conform to the change itself even when the unsustainable behavior is most common. Since many climate-friendly behaviors are not yet normative but are increasing in prevalence (e.g., reducing meat consumption, adopting energy efficient technologies) [77], existing injunctive and descriptive norms (and associated cognitive biases) may not favor their adoption, which poses a major challenge to climate change efforts [77,78]. In cases where prevailing norms reinforce unsustainable behavior, interventions that rely on them can inadvertently lead individuals who already engage in climate-friendly behavior at above-average levels to regress—a phenomenon known as the “boomerang effect” [28,69,76,79]. By emphasizing upward trends in climate-friendly behavior, dynamic norms may help counteract this effect. Growing evidence supports their effectiveness in climate change interventions, including for reducing meat consumption [76,80], using reusable cups [81], and conserving water [82]. Beyond environmental contexts, scholars have also found that dynamic norm interventions can increase policy support [83] and voter turnout [84].

In a field intervention of social norms on climate-friendly behavior, Schultz et al. [79] demonstrated the interacting effects of injunctive and descriptive norms on energy consumption. Within one neighborhood, they mailed some residents a descriptive normative message about average neighborhood energy use, while mailing other residents the same descriptive message with an additional injunctive norm (happy or sad icon) next to their household estimate [79]. The results demonstrated that the descriptive norm alone was effective at reducing energy use among residents whose energy consumption was higher than average [79]. However, for those with below-average energy use, the descriptive norm created a boomerang effect such that those residents increased their energy use to align with the perceived norm [79]. Schultz et al. [79] (and others; [69,85]) found that adding an injunctive norm eliminated this boomerang effect by reinforcing social approval for energy reduction. While Schultz et al. [79] also found that the combination of injunctive and descriptive norms enhanced the effectiveness of the intervention for households with above-average consumption, the overall evidence on whether using both norms together produces stronger effects remains mixed. In fact, one meta-analysis on conservation behavior found that descriptive norms alone had the strongest impact, followed by injunctive norms, and that messages combining both produced the weakest effects [74]. However, other meta-analyses have found that injunctive and descriptive norms have similar magnitude effects on PEB [70], or that injunctive norm manipulations are stronger influences on PEB than descriptive norm manipulations [86]. Because dynamic norms are a new area of research, evidence that compares their effectiveness with descriptive and injunctive norms is lacking.

This mixed evidence on the relative influence of different types of norms indicates that normative persuasion depends on contextual factors, such as the culture in which the intervention takes place. Cultures vary in their emphasis on collective goals (i.e., individualist vs. collectivist), tolerance for social norms transgressions (i.e., secular–rational vs. traditional), and degree of personal autonomy (i.e., self-expression vs. survival), among other attributes—all of which can shape the formation, strength, and effects of social norms on behavior [72,78,87,88,89,90]. For example, Ando et al. [91] found that subjective norms were more relevant than descriptive norms in Japan (a collectivist country), while the opposite was true in the U.S. (an individualist country), which they suggested was due to differences in how relationships define and influence identity in these cultures [91]. This same study also found that the effectiveness of these norms differed depending on whether the intervention targeted water use and shopping, energy conservation, or re-use behaviors [91], perhaps because some behaviors (e.g., reducing meat consumption) carry important sociocultural meanings that influence both the acceptance and impact of normative interventions [78]. While there is clear evidence that culture plays a role in normative persuasion [78], research has yet to establish consistent guidelines for predicting its influence in specific intervention contexts. Two meta-analyses found no significant effect of individualism vs. collectivism on PEB intentions or actions [59,70], while another found that norm-based PEB interventions were more effective in individualist than in collectivist cultures [72]—contrary to the study’s initial hypotheses and the findings of Ando et al. [91]. A fourth meta-analysis found that social norms regarding socially disapproved (vs. approved) behaviors were more influential in traditional and survival-oriented cultures than they were in secular–rational and self-expression cultures, but did not find significant cultural effects on normative persuasion overall [89].

Despite these mixed findings, social norms remain one of the most powerful mechanisms for promoting collective climate action over individual interests [6,47]. Rather than discouraging their use, these variations highlight the importance of identifying key audience characteristics when designing norm-based interventions [69,85]. Formative research can help identify the most salient and persuasive reference group for promoting climate-friendly behavior, as well as the type(s) of norms most likely to produce meaningful change in a given context. Generally, social norm interventions are most effective when the referent group is proximal, such as one’s neighborhood or close friends, though they can still promote behavior change at scale [47,58,69,89,92]. Additionally, normative information tends to be more persuasive when conveyed implicitly (e.g., through environmental cues such as lights being off when entering a room) rather than explicitly (e.g., through direct messaging about the importance of turning off lights) [72]. In part, this may be because normative messages that are perceived as coercive can trigger psychological reactance—the perception that one’s freedom to act or think in a specific way is threatened—which can cause the intervention to backfire [93]. Beyond influencing individual choices, social norms play a crucial role in political action by driving political pressure for ambitious climate policies. Moreover, policy itself can shape social norms by signaling societal approval of climate-friendly behaviors (injunctive norms) and by increasing their prevalence (descriptive norms) [69,78,94]; see [94] for information about influencing social norms through policy interventions.

2.3. Narratives

Though scientific data clearly demonstrate the rapid contribution of human GHG emissions to climate change on a geologic time scale [3], the consequences of climate change unfold slowly from the perspective of a human lifetime [17,18]. The experiential vagueness associated with not being able to directly perceive and experience climate change with our body and senses gives rise to myriad cognitive biases that interfere with climate-friendly behavior [17]. For example, climate action is thwarted by tendencies to notice and appreciate dramatic contrasting changes over gradual ones (contrast effect), to believe and remember information more easily when experienced directly rather than learned abstractly (i.e., through statistics and graphs; experience effect), and to accept and remember stories more easily than facts (story bias) [17]. These biases suggest that efforts to increase climate-friendly behavior will be more effective when they make the climate change feel personal and immediate—an approach supported by research on narrative persuasion.

Narratives, or stories of related characters and events that are connected in a causal chain with a distinct beginning, middle, and end, can be powerful channels for persuasion, and have a robust history in the context of entertainment–education programming [95]. Whether fictional or non-fictional [96,97], narratives provide the opportunity to embed persuasive (climate change) content into the plot of the story or into characters’ attitudes and behaviors, thus distributing pro-environmental messages without revealing their persuasive purpose [98,99]. Obscuring their persuasive intent allows narrative-based messages to limit the audience’s resistance to the persuasive content [100,101], which is especially useful when communicating climate change and other environmental information to polarized audiences [99,100,102], and in developing behavioral interventions [100,103].

Many theoretical approaches provide context for the ways that narratives overcome resistance to their persuasive appeals, e.g., [104], especially in the context of entertainment–education [100]. Most relevant to environmental interventions are social cognitive theory (SCT) [105,106] and the entertainment overcoming resistance model (EORM) [100]. SCT asserts that individuals form general rules about performing a specific behavior by observing the behavior of others and the outcomes of their actions [101,104,105,106]. According to SCT, when characters are rewarded for their behaviors, they vicariously reinforce the value of the action in the minds of the audience, which then motivates the audience to enact similar behaviors in the future [101,106,107]. Any modeled behaviors can motivate subsequent similar behaviors if the audience has sufficient attention, retention, production, and motivation (which includes feeling a sense of self-efficacy [106]). However, empirical evidence has confirmed that the more that viewers identify with the model, the more likely it will be that the audience enacts similar behaviors in the future [100,104,106,108,109].

Drawing from SCT, the EORM suggests that identification is one of several ways in which audiences can become involved with narrative characters—an overarching category which also includes wishful identification, perceived similarity, parasocial interaction, and liking [100,104,106]. Additionally, the EORM also suggests that persuasion is influenced by audiences becoming involved in the narrative storyline, otherwise referred to as transportation [100]. Transportation is a state of narrative immersion in which the audience devotes enough of their mental capacity to events within the narrative to temporarily suspend engagement with their own immediate environment [98,104,110]. According to the EORM, these two forms of involvement (character and narrative) reduce resistance to embedded persuasive messages by decreasing the audience’s inclination to counterargue against the narrative’s content [100,109] and their tendency to experience of psychological reactance [100,111,112]. Becoming involved in stories about climate change consequences can help counteract cognitive biases such as contrast and experience effects [17]. Furthermore, the ability to avoid reactance may be especially useful when handling divisive topics [99,113]—a category in which climate change certainly falls.

Beyond identification and transportation, narratives also promote persuasion by resonating more deeply with their audiences, stimulating stronger affective responses, and driving greater interest in their stories than information-based messages [98,99]. Information communicated through narratives is also easier to encode and transfer into long-term memory than information communicated through information-based reports [102,114,115]. Additionally, the affect-laden information delivered through narratives can make related attitudes more accessible [97], and has a higher chance of recall [98,116]. Narratives with subtle climate change messaging are also more likely to reach the audiences most in need of persuasion, given that they are less likely to fall victim to confirmation-biased selective exposure and attention [117,118]. Finally, narrative information is presented as the lived experience of characters, which are not subject to the same truth requirements as fact-based messages [98]. For these reasons, narratives have been found to produce stronger persuasive effects than information-based messages, both immediately following exposure and at delayed measurement [119].

In the domain of climate change, narrative-based interventions can be almost twice as effective at increasing climate-friendly behavior and intentions compared to traditional public service announcements (PSAs) and other fact-based messages [114,120,121]. In some cases, researchers have found that PSAs can even have deleterious effects on PEBs. For example, Morris et al. [121] found that that participants exposed to environmental PSAs were less likely to perform PEBs than participants who were not exposed to any environmental material. Further, Moyer-Gusé et al. [99] found that an episode of the situation comedy 30 Rock that featured a pro-environmental plotline effectively motivated PEB intentions; however, when commercial breaks also included pro-environmental PSAs, viewers with weak environmental attitudes experienced reactance and were subsequently less motivated to perform PEBs (see also [102]). In contrast, even text-based narratives with climate change content have been shown to facilitate experiential processing, increase affective engagement, and motivate climate-friendly behaviors both immediately and six weeks after exposure [121].

Although the persuasive potential of narratives is clear, there is still much to be understood when they are used to promote climate-friendly behavior. For example, transportation is frequently credited as a cause of persuasive outcomes in narratives, e.g., [104], and some research on environmental narratives indicates that transportation plays an important role in promoting PEB [122]. However, other research on climate change narratives has either failed to find that transportation is a significant moderator of PEB or that it has led to increased counterarguing with the narrative information [110,115,121]. Therefore, before intervention practitioners induce states of transportation to incite climate-friendly behavior, more research is needed to understand whether transportation can successfully persuade audiences in this context.

2.4. Framing

Framing is arguably the most popular and influential theory in the communication discipline [123], and has important implications for climate change messaging. To frame a message involves making some facets of a perceived reality more salient in a message “in such a way as to promote a particular problem definition, causal interpretation, moral evaluation, and/or treatment recommendation” [124] (p. 52). All messages inherently contain frames that can shape audience responses, as people tend to base decisions on the way information is presented in addition to, or sometimes instead of, the facts of the information itself (framing bias) [17,125], and to focus on only one or limited aspects of a situation when attempting to estimate a future outcome (focusing illusion) [126]. Because of these tendencies, climate change interventions can use frames strategically to highlight aspects of the issue that are most likely to persuade the target audience, e.g., [127].

In the persuasion literature, framing is generally categorized as either emphasis or equivalence framing. Emphasis framing, in which certain aspects or attributes of a topic are promoted over others [127,128,129], can be particularly useful in persuading those resistant to climate change belief or action. Emphasis framing selects particular aspects of reality to make salient while also directing attention away from other aspects [124]. This omission of other perspectives, explanations, and/or recommendations can be just as critical in persuasion as the inclusion of the selected information [124], and is one reason for the popular use of frames among environmental communication scholars. Indeed, describing the potential benefits of a cleaner and healthier way of life is clearly a more persuasive approach to motivate climate-friendly behavior than describing the financial costs of transitioning to greener energy [17]. Emphasis frames can also selectively omit climate change information that is often associated with polarized responses, such as its anthropogenic causes and moral responsibility for action, and instead highlight other contributions of climate-friendly behavior, such as economic gains, national security, or the health of one’s family and children [17,128,130]. For example, framing solar panels or electric vehicles as status symbols can focus attention toward social approval one could gain from investing in these technologies, while downplaying (or omitting) polarizing perspectives on individual responsibility for climate action [17,24,131].

Unlike emphasis framing, which selectively presents different content in persuasive messaging, equivalence framing presents the same information from different orientations [127,129]. The most common form of equivalence framing contrasts gains and losses. Grounded in Kahneman and Tversky’s [132] prospect theory, gain–loss framing plays into the notion that individuals are more risk-averse when an outcome is framed as a potential gain (e.g., addressing climate change will save 70% of crops) than when the same outcome is framed as a potential loss (e.g., failing to address climate change will destroy 70% of crops), reflecting both loss aversion and risk perception biases [19,32]. From this perspective, emphasizing the severe consequences of climate change and the scarcity of environmental resources may be a more effective approach than focusing on the potential benefits from taking action [17]. Although some evidence suggests that highlighting environmental (or related economic, social, and material) losses can be more persuasive than emphasizing corresponding gains, e.g., [133], research on gain vs. loss framing in both environmental communication and the broader persuasion literature has yielded mixed results [127,134,135]. Similar to social norms, cultural influences may contribute to these inconsistencies, given that the cultural cognition of risk theory suggests that cultural values shape the way people evaluate risk (potential losses), empirical evidence, and scientific consensus [136]. However, research does consistently find that loss-framed messages evoke more fear than gain–framed messages, which itself can drive climate-friendly behavior under the right conditions [127,137,138,139].

2.5. Emotions

Nabi [140] proposed an emotions-as-frames model, which suggests that emotions can serve as frames by increasing the accessibility of certain information and guiding the interpretation of incoming stimuli. In addition, each emotion provokes distinct patterns of appraisals and action tendencies, which represent biological urges to act according to the emotion’s motivational goals [140,141]; thus, each emotional frame contributes unique potential to increasing climate-friendly behavior. People tend to overestimate the intensity and duration of their future emotions (affective forecasting; impact bias) and also make decisions based on what feels emotionally “right” (affect heuristic) [17,142,143], making emotions important drivers of behavior. Because of this, emotions—especially fear, pride and guilt, and hope—have received much attention in the PEB literature as potential points for intervention. Indeed, one meta-analysis of interventions to influence climate change attitudes found that, despite the small effect sizes overall, interventions that evoked emotional responses produced the largest effects [144].

Table 2. Comparison of Fear, Pride and Guilt, and Hope in Promoting Climate-Friendly Behavior.

Emotion	Definition and Key Features	Contributions to Climate-Friendly Behavior	Challenges and Considerations
Fear	A response to perceived threat (i.e., climate change) that can drive protective action. Theories include the parallel process model (PPM), protection motivation theory (PMT), and the extended parallel process model (EPPM).	Fear appeals involve establishing perceptions of severity, susceptibility, self-efficacy, and response efficacy. May enhance message elaboration and long-term behavior change. Already used widely in climate change messaging.	Climate threats are often distant and abstract, so establishing personal susceptibility is both necessary and challenging for persuasion. Potential for fatigue due to frequent use in the media. Domain-specific evidence is lacking.
Pride and Guilt	Self-conscious emotions based on evaluating behavior against personal or social norms. Pride arises from positive actions, whereas guilt arises from failing to meet environmental standards.	Pride can reinforce positive behaviors and encourage sharing success. Guilt can motivate reparative actions. Anticipated emotions (e.g., avoiding future guilt) can be even stronger motivators than experienced emotions.	Effects depend on individual and socially normative differences in pro-environmental attitudes and behaviors. Using felt guilt requires engagement in environmentally detrimental behavior
Hope	A future-oriented emotion that attunes individuals to desired future outcomes and/or the possibility of relief from a negative situation. Linked to high coping potential and self-efficacy.	Encourages engagement when focused on personal action. Can enhance motivation by pairing with fear in emotional flow (fear → hope).	Can be demotivating if focused on complacency (“hopium”). Hope appeals highlighting societal efficacy may not be effective.

Note. PEB = pro-environmental behavior; PPM = parallel process model; PMT = protection motivation theory; EPPM = extended parallel process model.

compares these prominent emotions in climate change interventions, including their contributions to and limitations for increasing climate action.

2.5.1. Fear

The connection between fear and climate change is apparent to journalists and researchers alike [145]. The theoretical basis of persuasive fear appeals includes the parallel process model (PPM) [146], protection motivation theory (PMT) [147], and the extended parallel process model (EPPM) [148]. These theoretical approaches suggest that an individual’s experience of fear is determined by four cognitions: (a) the individual’s perceived severity of a threat and (b) their personal susceptibility, along with their perception that they have the efficacy to protect themselves from the threat, which conceptually includes both (c) self- and (d) response efficacy. Not all aspects of these theories have been validated, such as the interaction between perceived threat and efficacy in the EPPM, or predictions of a curvilinear relationship between fear and message acceptance [148] (though there is evidence for a within-subjects curvilinear relationship between fear and persuasive outcomes) [149]. However, meta-analyses do support a linear relationship between fear and persuasive outcomes, especially when accompanied by efficacy information [150]. Fear may also promote message elaboration, making long-lasting attitude and behavior change more likely [98,151].

Although fear appeals are already common in climate change media through the highlighting of consequences such as natural disasters and the decline of polar bears, their use as an intervention tool is mostly based on evidence from the field of public health [39]. Not only is evidence from the domain of climate change lacking, but the use of fear appeals in climate change communication has shown mixed results overall [39,151]. The lack of consistent persuasive effects of fear appeals within climate change communication research may be partially due to the delayed and distant threats associated with climate change impacts, in which future generations, individuals in the Global South, and other species are more susceptible [152,153], which fuels the tendency to discount climate change consequences (discounting bias) [17]. Supporting this idea, Kothe et al.’s [39] systematic mapping review of PMT and PEB found that the susceptibility construct has more consistent relationships with PEB intention than does severity, suggesting that those who do not feel susceptible to (distant, removed, and hypothetical) environmental threats are unlikely to take action, regardless of the perceived severity of these threats. Additionally, the already ubiquitous use of fearful language and images used in climate change descriptions [151], and the high levels of climate change worry among most individuals [154], may result in fatigue that limits the novelty and corresponding effectiveness of climate change fear appeals. There is an unmistakable urgency to communicate the gravity of impending climate consequences if action is not taken, which will continue to result in the use of fear-based messaging, whether intentionally persuasive or not [144,151]. Therefore, both researchers and practitioners will benefit greatly from additional research and theorizing in the area of climate change fear appeals [39,155,156].

2.5.2. Pride and Guilt

Pride and guilt are both self-conscious emotions, which “arise from a self-evaluation of one’s behavior in accordance with personal or social normative beliefs” [157] (p. 1). Whereas pride is a positive feeling that is evoked when individuals believe that they have performed a desired behavior, guilt’s negative affect arises when people believe that they have violated acceptable, or moral, rules of conduct [157,158,159]. In line with the emotions’ action tendencies, individuals who experience feelings of pride may continue their (climate-friendly) behavior and share their success with others, whereas those who experience guilt are likely to seek ways in which they can make reparations by engaging in positive (climate-friendly) behavior [158,159]. Both pride and guilt as driving forces of PEB have received extensive attention in the literature [157], and climate change interventions can evoke pride and/or guilt by prompting individuals (especially those with preexisting pro-environmental attitudes) to self-reflect or evaluate their environmental behavior. For example, Hurst and Sintov [160] evoked feelings of pride (guilt) by telling participants that their home energy use was smaller (larger) than 85% of other people (study 1), and by communicating they had supported a company with a smaller (bigger) carbon footprint than other similar companies; these emotions then predicted their PEB intentions (study 1) and decision to donate to an environmental organization (study 2). Because pride and guilt are self-conscious emotions, they can also arise through social norms appeals such that adhering to (diverging from) social norms inspires pride (guilt), which then motivates PEB [161].

In addition to the experiences of pride and guilt driving increased engagement in PEB [157], both emotions can also function anticipatorily to encourage climate-friendly behavior. Anticipated emotions are expected emotional states that arise as a consequence of considering potential future behavioral decisions [162,163]. Anticipated pride and guilt can arise when people are asked to think about how they would feel if they acted unsustainably, such as by considering how they would react if they learned that their carbon footprint was higher than most others [160]. Perhaps because of biased affective forecasting, meta-analyses suggest that the anticipation of these emotions is just as, or even stronger than, their experienced counterparts [157]. In the case of guilt, interventions that evoke the anticipation of this emotion are especially promising given that they can prevent individuals from performing environmentally detrimental actions in the first place.

2.5.3. Hope

Hope is a future-oriented state that attunes individuals to desired future outcomes and/or the possibility of relief from a negative situation [141,164]. According to appraisal theories of emotion, hope reflects high coping potential, which motivates individuals to pursue their goals [165,166]. In this way, hope is conceptually linked to self-efficacy cognitions [166,167], and extant research has found correlations between the two constructs [168,169].

Although hope and efficacy may work in tandem to encourage behavior [167,169,170], it is unclear whether evoking hope as an intervention tactic can consistently motivate climate-friendly behavior on its own. Hope can be persuasive in some contexts, but the emotion can also exert a “pleasant yet sedating, demotivational effect” sometimes referred to as hopium, which works counter to persuasive goals [164] (p. 2). In the context of climate change interventions, the motivational effects of hope may depend on what individuals are being made hopeful for [164]. For example, in a meta-analysis of hope and climate engagement, Geiger et al. [164] found that feeling hopeful for the possibility of taking action was strongly associated with climate-friendly behavior, whereas hope in relation to climate change not posing a problem was associated with decreased engagement in climate-friendly behavior. Furthermore, hope appeals highlighting personal efficacy to address environmental problems promoted climate-friendly behavior, whereas those that highlighted societal efficacy had no impact [164]. Overall, this meta-analysis suggests that the use of hope as a motivator of climate action shows promise, but that practitioners must be cautious to evoke hope associated with one’s own environmental action.

Beyond the isolated use of hope appeals, hope may also play a role in climate change interventions as one component of emotional flow [127,171]. The concept of emotional flow suggests that the progression from one emotion to the next can encourage persuasive outcomes [171]. For example, climate change messages that evoke fear and then hope, in sequence, have been shown to be more persuasive than messages that lack this progression [127]. This framework may be especially suited for narrative formats, in which there is already a framework for shifting audience emotions over the course of a message. Interestingly, while narratives that progress from fear to hope have improved the message receiver’s self-efficacy to avert a threat [169,170,171], reversing the emotions has been found to negatively affect self-efficacy [170], which can be detrimental to taking climate action. As additional research clarifies the persuasive implications of hope, scholars and practitioners may find that its greatest persuasive potential lies in its ability to strengthen efficacy appraisals within the context of climate change fear appeals.

3. New Directions for the Intersection of Persuasion and Climate Action: Message Tailoring and Personalization

The rise of social media, algorithms, and artificial intelligence (AI) has enabled interventions to direct targeted messages to specific audiences, maximizing their potential for impact. Tailored and personalized messages align the message content with characteristics of the target audience, which increases the likelihood that the audience will perceive them as relevant [172,173,174,175]. Because the messages are more relevant, tailored and personalized interventions are more likely to be seen and consumed by the audience [176], carefully processed [177,178], liked and remembered [179,180], and to ultimately change their attitudes and behavior [181,182,183]. Given that climate change messaging is known to have polarizing effects [184,185], crafting messages to persuade specific target audiences enables climate change interventions to emphasize the elements most likely to resonate with those in greatest need of behavior change.

3.1. Tailoring Climate Change Interventions

Tailoring involves customizing messages with one or more demographic, physiological, or behavioral characteristic(s) of the target audience [186]. In environmental research, scholars have long acknowledged that different interventions are needed to persuade individuals who are already environmentally aware compared to those who are not [5,187], and for liberal audiences compared to conservatives [130,144]. Based on established differences in climate action across political ideologies and climate awareness, two promising theoretical approaches to climate change interventions include tailoring to the audience’s moral values as informed by moral foundations theory (MFT) [188], and to their stage of change as informed by the transtheoretical model (TTM) [189]. Preliminary findings at the frontier of environmental tailoring research suggest that tailored interventions produce the largest behavioral effects [190,191], though much more research on message tailoring is needed in the domain of climate change.

3.1.1. Moral Foundations Theory

MFT proposes that liberals and conservatives rely on different (though overlapping) sets of moral values to guide their attitudes and behaviors. Specifically, liberals tend to be more persuaded by individualizing frames that reflect concern for individual rights and welfare by emphasizing harm/care and fairness/reciprocity, while conservatives are also persuaded by binding moral frames that reflect an attempt to maintain social order by emphasizing in-group loyalty, respect for authority, and purity/sanctity [130,188,192]. Regrettably, most climate change messages preach to the converted [193] in that they are framed implicitly or explicitly with moral emphases that most resonate with liberal audiences [130,192,194], despite liberals being more environmentally oriented on average [195,196].

In climate change interventions, using moral frames tailored to the target audience can increase persuasive success in a variety of ways. First, people have a tendency to see, focus on, and remember information that aligns with their existing beliefs and expectations (confirmation bias) [17,30]. Therefore, messages that are framed according to the audience’s moral values can prevent selective exposure/avoidance, or the tendency for individuals to discount information that goes against one’s worldview [113], and are often perceived as presenting stronger arguments [130]. Tailoring using moral frames can also cater to people’s tendencies to favor in-group interests (in-group/out-group bias) [17,32], by describing climate change information in ways that resonate with the audience’s political identity. Finally, matching moral frames to the audience can increase the perceptual fluency of the message, which facilitates comprehension and promotes feelings of desirability [192].

Thus far, using moral foundations to tailor climate change messages has shown considerable success. Simply framing the same climate change information using moral values that resonate more strongly with conservatives, such as highlighting impacts to the purity of pristine landscapes or national security as a result of climate change [197], has been shown to nearly eliminate the differences in environmental attitudes across the political spectrum [130,192]. For example, Wolsko et al. [130] found that when both liberals and conservatives were exposed to climate change information that emphasized a binding moral frame typically associated with conservatives, the difference in climate change attitudes between liberals and conservatives became non-significant. Similarly, Hurst and Stern [198] found that conservatively framed messages increased conservatives’ concern about fossil fuels and support for cleaner energy, especially when the messages were also delivered by a conservative source. Future research is needed to determine which message components are the most morally affirming among different audiences, and which moral frames can engage audiences across political lines [113,130]. However, current findings suggest that tailoring messages based on moral value frames has great potential to promote PEB across political lines.

3.1.2. The Transtheoretical Model of Behavior Change

The TTM was originally developed as a tool to help tailor health interventions [199,200], and has only recently received attention in the context of climate change interventions [66,201,202]. The TTM suggests that behavior change unfolds over time as a progression through a series of stages: precontemplation (not ready), contemplation (getting ready), preparation (ready), action (active), and maintenance (preventing relapse) [189,203]. By conceptualizing behavior change as a process of increasing readiness to perform an action, as opposed to as a singular event, the TTM enables researchers and practitioners to tailor different types of persuasive information based on the extent to which the target groups are more or less ready for action [199,201,204]. This is a noteworthy contribution to intervention research, as it is unrealistic to assume that individuals who never considered changing their behavior would respond to interventions in the same way as those who already want to take action [189]. Further, people are predisposed to focus on intermediary steps rather than the final objective (surrogation bias) [17,205], suggesting that interventions will be most impactful when they promote advancement through specific stages rather expecting people to navigate through these stages on their own. Supporting this idea, Doran et al. [202] propose that inconsistent findings in the literature on climate change interventions may be partially a consequence of the different samples being, on average, at different stages of change.

The TTM suggests that there are three supporting constructs that facilitate individuals’ progression through the stages of change: processes of change, decisional balance, and self-efficacy [189]. Although the processes of change were theorized to represent the “covert and overt activities that people use to progress through the stages,” the evidence has not supported their uniform application as predicted [189] (p. 62). In contrast, decisional balance and self-efficacy have shown systematic relationships with the stages of change, and thus provide helpful guidance for climate change interventions [189,201].

Decisional balance represents the relative importance of advantages and disadvantages of adopting the target behavior. According to the TTM, the decisional balance will favor pros of changing more heavily than cons as individuals advance through the stages of change [189]. In fact, meta-analyses examining the use of the TTM in public health research have confirmed that, on average, individuals experience a one standard deviation increase in the pros of changing (strong principle), and a ½ standard deviation decrease in the cons of changing (weak principle) as they progress from precontemplation to action [189,199]. If these findings replicate in climate change interventions, it would suggest that interventions should highlight approximately twice the number of advantages for action as counteracting barriers to change. Additionally, results from both health and environmental research have demonstrated that self-efficacy generally increases as individuals progress through the stages of change [202]. Although efficacy information can be valuable at every stage, its behavioral impact may be most pronounced for individuals in the preparation stage [206]. Furthermore, Doran et al. [202] suggest that different types of efficacy information may be more valuable in different stages; for example, individuals in precontemplation may require directional information regarding how to perform a behavior, while individuals in contemplation or action may require specific tips to circumvent identified obstacles. Thus, researchers and intervention practitioners should also consider tailoring the type of efficacy information to the target audience’s stage of change.

The TTM’s central contribution to persuasion—that different persuasive information is needed as individuals progress through the stages of behavior change—can be integrated with most of the theoretical frameworks described thus far. For example, within the TPB, adding a stage of change variable has been shown to explain more variance in behavior intention [207]. In addition, the relative impact of subjective norms has been shown to differ across stages of change [208], which suggests that norms-based interventions will benefit from understanding how close the target audience is to action. Although there are frequent calls to tailor climate change interventions to the stage of the target audience [5,201,202,209], this is still an emerging area of research. Additional research is needed in the environmental domain to validate stage of change measures, which are currently limited to single self-report items, and to determine the best intervention tactics to advance individuals at each stage.

3.2. Personalizing Messages for Climate Change

AI has enabled precise and automatic matching of individual user data to online messages through the process known as personalization [210]. Regardless of whether personalization is minimal (e.g., simply including the individual’s name) or more advanced (e.g., recommending products or services based on their online data), personalized messages are generally perceived as being more memorable, likable, and credible than non-personalized messages [180,211]. In turn, personalized messages subtly influence users’ attitudes, behaviors, and self-concepts in ways that often extend beyond their initial preferences [183,212,213]. These covert yet powerful persuasive effects of personalization may offer new opportunities for climate change interventions to expand their reach without compromising effectiveness, e.g., [214].

Although personalization implies matching content to a specific user, it is the perception of personalization, rather than the actual degree of personalization, that drives persuasive outcomes. Simply communicating that a message is personalized promotes persuasion, even if the message does not fully reflect the users’ preferences or behaviors (or does not reflect them at all) [183,213,215]. Major technology platforms, including Amazon, Spotify, and social media companies, have long leveraged the persuasiveness of perceived personalization to encourage behaviors that increase company revenue [180,216,217,218]—in the case of Netflix, by as much as 1 billion USD/year [219].

Although personalization research has traditionally focused on brand attitudes and purchase intentions, personalized messaging can also be used to promote climate-friendly behavior. For instance, Summers et al. [183] found that telling participants that a recommendation for an eco-friendly product was personalized increased their willingness to make eco-friendly purchases, even though the recommendations were not actually personalized. Moreover, these “personalized” eco-friendly recommendations strengthened participants’ environmental self-perceptions [183], supporting the idea that individuals can learn about themselves through personalized content [183,212,220,221]. These findings suggest that personalized messages that frame the recipient as someone who chooses to act sustainably may increase the recipient’s tendency to prioritize the environment. Though this is an emerging area of research, it highlights the potential for interventions that deliver personalized climate-friendly recommendations to drive both short- and long-term behavior change.

The potential to promote climate-friendly behavior through personalized AI recommendations holds tremendous potential, given the wide reach of AI personalization. Most other environmental interventions must balance reaching large heterogeneous audience with decreasing effect sizes due diminishing contextual relevance at scale [47,214]. However, personalized climate change recommendations may be able to achieve both, given the reach of AI and the relevance of personalization. An example may be illustrative. Imagine that Amazon introduced environmental priorities into its algorithm such that products were both filtered according to their match with the user’s data as well as their environmental impact. Because the recommendations would still be personalized, and because the perception of personalization is more important to persuasion than the extent of actual personalization [215], it is likely that Amazon users would begin to purchase more sustainable products. Even if the increase in sustainable recommendations was minimal, the incredible reach of the Amazon platform may result in substantial cumulative environmental effects. Finally, given that eco-friendly recommendations can strengthen users’ environmental self-perception [183], people who begin to purchase climate-friendly products may increasingly see themselves as more eco-friendly in general, and engage in climate action in other ways.

While purchasing products on Amazon has other negative climate change consequences associated with consumption and GHG emissions [222,223], the potential for these systems to increase climate-friendly behavior lies in changing the consumption patterns and self-perceptions of those who are already interacting with these platforms. Further, AI use is most common among the same demographic segments that are responsible for the majority of global environmental degradation [224,225]. Therefore, increasing PEB among AI users through personalization contributes to environmental justice by targeting those most responsible for change. Although recent evidence indicates that this strategy for intervening in climate action shows promise, much additional research is needed to understand the environmental outcomes associated with this type of climate change intervention.

4. Discussion

Climate change is one of the most prominent public and political issues facing current generations [226]. Atmospheric carbon dioxide levels are higher than at any point in the last two million years, the frequency and severity of natural disasters are intensifying, and there are few credible plans to avoid breeching established safe temperature thresholds [3]. This review argues that political, economic, and technological innovation must be paired with an understanding of human behavior change to effectively mitigate climate change impacts. By drawing from persuasion research, climate change interventions can maximize urgently needed increases in climate-friendly behavior across individual, organizational, and political contexts.

The theoretical frameworks reviewed in this paper were selected for their broad applicability to both persuasion and environmental interventions. Other syntheses of environmental intervention research offer valuable insights into key theoretical perspectives that can promote climate-friendly behavior [5,15,28,227]. This review builds on prior work by grounding climate change intervention research in the theoretical frameworks of persuasion, providing a deeper understanding of the mechanisms driving behavior change in the context of climate action. In doing so, it also considers how cognitive biases may shape responses to interventions (see

Table 3. Select Cognitive Biases Relevant to the Reviewed Theoretical Frameworks.

Persuasion Theoretical Framework		Select Cognitive Biases
Theory of Planned Behavior		Confirmation bias, risk perception bias
Social Norms		Bandwagon effect, conformity bias, in-group/out-group bias
Narrative-Based Persuasion		Contrast effect, experience effect, story bias
Framing		Availability bias, focusing illusion, framing bias, loss aversion, risk perception bias
Emotions
	Fear	Availability bias, loss aversion, risk perception bias
	Pride and Guilt	Affect heuristic, affective forecasting, availability bias, confirmation bias, in-group/out-group bias
	Hope	Optimism bias
Message Tailoring
Moral Foundations Theory		Confirmation bias, framing bias, in-group/out-group bias
Transtheoretical Model of Behavior Change		Surrogation bias
Personalization		Confirmation bias, framing bias

for relevant biases).

Although each persuasion framework described in this review contributes unique insights into human behavior change, they need not be applied independently. In fact, existing evidence suggests that the most effective interventions are those that combine relevant insights from a variety of theoretical perspectives to develop strategies best suited to the specific intervention context [5,28,65,66,228]. Further, these frameworks should not be applied indiscriminately, as a central lesson from persuasion research is that persuasion is most effective when based on an understanding of the specific intervention context [229]. Still, general guidelines for climate change interventions can be drawn from each area.

4.1. Practical Guidelines for Climate Change Interventions

The theory of planned behavior (TPB) provides explicit guidelines for conducting formative research to understand the underlying beliefs and motivations of the target audience. By first identifying contextually specific barriers to climate action, the TPB enables interventions to focus efforts on alleviating the barriers that pose the greatest hindrance to climate-friendly behavior. In this way, the TPB tells us that while climate change interventions may share similarities, promoting climate action requires addressing challenges that are idiosyncratic to each context. Perhaps because of this level of detail, the TPB is particularly helpful for encouraging difficult or effortful behaviors [5,44,62]. The TPB proposes that one’s attitudes, subjective norms, and perceived behavioral control are the three central antecedents to behavior intention and action, and the centrality of these constructs has received widespread support [230]. However, the TPB is also easily extended with additional constructs as deemed important to the intervention context [49]. In fact, 72% of articles analyzed in the scoping review of the TPB and PEB extended the model with variables such as personal moral norms, self-identity, anticipated emotions, environmental awareness, other social norms, and stage of change [49,69,207]. Extending the TPB with contextually relevant variables can help overcome criticisms related to its omission of emotional and habitual processes.

Social norms are widely used in climate change interventions, and have produced some of the largest effect sizes in the field [47,231]. Individuals often underestimate the influence of social norms on their behavior, allowing (especially implicit) normative appeals to promote persuasion through unconscious processes [68,71]. Although social norms are highly effective regardless of whether the behavior requires short- or long-term investments or the amount of effort required to comply [70,89], formative research is also necessary in this context to identify (a) the salient reference group, (b) the preexisting norms of the target audience, and (c) the effects of social influence in that behavioral and cultural context. This formative research can help the intervention planner determine whether descriptive, injunctive, dynamic, and/or other types of norms will promote the most favorable behavior change and prevent unfavorable boomerang effects and psychological reactance.

Research on narrative persuasion reveals that climate change information is more likely to reach and persuade polarized audiences when embedded in a story rather than presented as facts, statistics, or public service announcements. Narratives that incorporate climate change information can subtly educate audiences, enhance their sense of efficacy in performing climate-friendly behaviors, and increase climate action without explicitly calling for change. To enhance persuasion, narrative-based interventions should use characters that the target audience is most likely to identify with. This can be achieved by selecting characters the audience likes, perceives as similar to themselves, finds attractive, admires, and considers part of their in-group [17,100,106]. Therefore, using narratives to promote climate-friendly behavior also requires understanding the target audience to determine the message content and source that will maximize persuasion, as well as to identify the media channel through which the audience is most likely to be exposed. Although it may be tempting to include explicit calls to action to ensure that the subtle climate change information is understood, piloting this approach before implementation is essential, given that it has been shown to backfire in empirical research [121].

Frames can be used strategically in climate change interventions to present information in ways that are most likely to persuade. When targeting audiences with low environmental concern, emphasis framing can focus attention on the personal benefits of climate-friendly behavior that are most likely to resonate with the audience, while directing attention away from polarizing information, such as its anthropogenic causes and consequences, that could provoke resistance. In contrast, selecting an appropriate equivalence frame requires understanding the most persuasive way to describe the same content. Theoretical approaches to equivalence framing suggest that framing outcomes in terms of potential losses should be more persuasive than framing them in terms of potential gains, as loss frames leverage loss aversion and risk perception biases. However, meta-analyses do not support the overall effectiveness of loss over gain framing [127,134,135], also highlighting the need for formative research. Still, interventions that employ loss framing can evoke stronger feelings of fear, which in turn may drive climate action.

Emotions such as fear, pride, guilt, and hope are already inherent in climate change messaging, creating easy opportunities for interventions to enhance their persuasive impact. Given the prevalence of fear appeals in everyday climate change communication, their ability to motivate climate-friendly behavior depends on whether the audience is made to feel susceptible to the threat and capable of averting it. Pride derived from taking climate action and guilt from unsustainable activities can both increase engagement by encouraging people to self-reflect on their behavior. Interventions can also encourage people to consider how they would feel about (not) acting sustainably, as the anticipation of these emotions can produce similar effects while preventing initial environmentally harmful behavior. While hope is becoming increasingly essential for sustaining climate-friendly behavior amid adverse climate policies and stagnant political action, interventions should be careful to evoke hope in one’s ability to act rather than hope that climate change will resolve on its own. Additionally, generating feelings of hope immediately after a fear appeal may enhance the persuasive impact of both emotions [127]. Because people tend to overestimate the impact of their emotions and base decisions on them [17], framing climate change messaging to evoke emotional responses can be highly persuasive [140,144].

The rise of social media, algorithms, and AI has created new opportunities for persuasion research to inform climate change interventions. Tailoring messages to the target audience allows interventions to focus effort and resources on segments of the population that most require behavioral change. When interventions aim to increase climate-friendly behavior among conservative audiences, tailoring messages based on the moral values that resonate most with conservatives increases the likelihood that these messages will be seen, appreciated, remembered, and ultimately change behavior. Additionally, the transtheoretical model highlights the need for different interventions depending on the audience’s stage of environmental engagement. For those who are ready to take action and need only a small push, interventions can provide strategies to overcome specific barriers (which can be identified through formative research using the TPB). For those who have not yet begun to contemplate climate-friendly behavior, interventions can focus on raising awareness and shifting the perceived pros and cons of sustainable behavior (i.e., through narratives, framing, and social norms appeals).

With the increasing power of algorithms, interventions may also be able to leverage the persuasive effects of personalized messaging to recommend specific climate-friendly behaviors and choices to technology users. While this is still an emerging area of research, existing evidence suggests that personalized eco-friendly messages can influence attitudes, behaviors, and environmental self-perception, suggesting their potential to drive widespread and long-lasting change.

There are many additional theories and frameworks from both the persuasion and environmental behavior literature that can help guide climate change interventions, including self-determination theory [232,233], the health belief model [234,235], goal-framing theory [236], the norm activation model [25], and the value–belief-norm theory of environmentalism [228]. Those working to increase climate-friendly behavior are encouraged to explore additional behavior change research that can help inform the development of evidence-based interventions that will best persuade their target audience to enact a specific climate-friendly behavior.

4.2. Additional Considerations

When designing climate change interventions, consideration should be given to their reach, effect, and durability [47,214]. According to Goldberg and Gustafson [214], reach refers to the number of people exposed to the intervention, effect refers to the extent to which those exposed are impacted, and durability refers to the duration that the effect persists over time and/or resists opposition. Often, empirical tests of environmental interventions focus solely on significant effects at the expense of the reach and durability of these strategies in practice [214]. As an example, consider the effects of social norms interventions, which may achieve the largest effect sizes when they reference a proximal in-group, such as those who occupy the same physical space as the target, one’s neighborhood, or one’s close friends [47,89,237,238]. However, narrowing the scope of the intervention to a single neighborhood or friend group limits the reach of the intervention to fewer individuals. This tradeoff between reach and effect is demonstrated in two meta-analyses of field interventions for PEB (one being a second-order meta-analysis [72]), which both found that the average effects of the interventions decreased from approximately seven percentage points to two when examining studies with large sample sizes [47,231].

Another consideration related to the magnitude of the effect is the extent to which significant changes to individual behavior translates to meaningful environmental protection. Many PEB interventions promote behaviors that are easy to target experimentally but that have little environmental consequence, such as recycling, using reusable bags, foregoing plastic straws, and other low-cost PEB [239,240,241]. Because of this, the effect sizes associated with behavioral changes may not relate to the magnitude of environmental protection. The focus on behavioral outcomes is understandable, given that social scientists are trained to focus on behavioral outcomes and the relative infrequency of high-impact PEB makes data collection expensive, challenging, and time consuming [47]. Although the study of high-impact PEB presents challenges, considering environmental alongside behavioral effects is imperative if these interventions are to contribute to mitigating climate change impacts [47,227,228,242].

Finally, while most research on climate change interventions focuses exclusively on changing behavior [23], the durability of climate-friendly behaviors over time is also essential. Unfortunately, behavior maintenance has received less attention in the literature [23,66], and a meta-analysis on the long-term effects of climate change interventions suggests that most effects are short-lived [231]. While this finding may seem discouraging for the efficacy of climate change interventions, three important points should be considered. First, interventions that not only change behavior but also influence environmental attitudes and self-perceptions are more likely to encourage future action, as they promote the internalization of environmental goals [183,231]. Second, interventions that foster climate-friendly habits (e.g., through repeated behavior) may be more likely to sustain behavior over time [17,231]. Third, some of the most impactful climate-friendly actions require a large upfront cost or effort for adoption but demand little or no additional maintenance (e.g., purchasing an electric car, replacing gas appliances with electric alternatives) [23], indicating that focused efforts on adopting high-impact behaviors may lead to long term reductions in GHG emissions. Ultimately, prioritizing interventions that consider reach and durability alongside both behavioral and environmental effects can maximize their contribution to climate change efforts.

5. Conclusions

Combatting climate change requires concerted efforts to change human behavior as efficiently and effectively as possible. Applying persuasion research to these efforts can help shape climate change interventions around the determinants that have demonstrated ability to motivate climate-friendly behavior. This review highlighted several useful persuasion theoretical frameworks for increasing climate-friendly behavior, including the theory of planned behavior, social norms, narratives, framing, and emotions, and suggested new opportunities to tailor and personalize messages using AI. To accomplish the goal of increasing global climate action, however, interventions must be developed to address the needs and barriers of their specific context. Additionally, research efforts at the intersection of persuasion and climate change interventions must evolve alongside changing environmental threats and persuasive channels, while devoting increased attention to the intervention tactics that generate the largest practical environmental outcomes. There are myriad opportunities for future research at the intersection of climate change interventions and persuasion, the results of which can be used to guide meaningful efforts to increase climate action on individual, organizational, and policy levels.