Indigenous mental health in a changing climate: a systematic scoping review of the global literature

Indigenous Peoples globally are among those who are most acutely experiencing the mental health impacts of climate change; however, little is known about the ways in which Indigenous Peoples globally experience climate-sensitive mental health impacts and outcomes, and how these experiences may vary depending on local socio-cultural contexts, geographical location, and regional variations in climate change. Thus, the goal of this study was to examine the extent, range, and nature of published research investigating the ways in which global Indigenous mental health is impacted by meteorological, seasonal, and climatic changes. Following a systematic scoping review protocol, three electronic databases were searched. To be included, articles had to be empirical research published since 2007 (i.e. since the Intergovernmental Panel on Climate Change’s Fourth Assessment Report); explicitly discuss Indigenous Peoples and describe factors related to climatic variables and mental health. Descriptive data from relevant articles were extracted, and the articles were thematically analyzed. Fifty articles were included for full review. Most primary research articles described research in Canada (38%), Australia (24%), and the United States of America (10%), with the number of articles increasing over time. Mental health outcomes such as strong emotional responses, suicide, depression, and anxiety were linked to changes in meteorological factors, seasonality, and exposure to both acute and chronic weather events. The literature also reported on the ways in which the emotional and psychological impacts of climate were connected to changing place attachment, disrupted cultural continuity, altered food security and systems, forced human mobility, and intangible loss and damages. This review highlights global considerations for Indigenous mental health in relation to climate change, which can support Indigenous-driven initiatives and decision-making to enhance mental wellness in a changing climate.


Introduction
Mental health has been recognized as a major concern in the context of climate change [1][2][3][4], reflected in burgeoning research, programming, and public interest [1,2,[4][5][6][7][8][9][10]. There are many known and anticipated causal pathways through which climate change and the resultant environmental shifts impact mental health, including: acute trauma and distress resulting directly from exposure to severe weather events [5]; disruptions to the underlying determinants of mental health, such as physical health, infrastructure, and social capital [e.g . 11]; and altered connections to place that threaten knowledge systems and cultural practices [e.g. [12][13][14][15]. Population-level studies based on hospital and national mortality databases have indicated that changes in weather and seasonality are associated with mental health-related hospital visits [e.g. 16,17], interpersonal conflict [e.g. 18], and suicide [e.g. 4,19]. Globally, the burden of mental illness is projected to rise [20], with climate change identified both as a magnifier of already-present mental health challenges, as well as directly and indirectly leading to new climate-sensitive mental health stressors and outcomes that are complex, cumulative, wide-ranging, and far-reaching [11,21,22].
The mental health impacts of climate change are amplified among certain populations, including those living in ecologically sensitive areas; those who rely closely on their environment for subsistence and livelihoods; those who already struggle with chronic health issues; and those experiencing ongoing systems of inequity, marginalization, and colonization, such as many Indigenous Peoples globally [1,[23][24][25][26]. As such, climate change and resulting environmental changes not only risk amplifying existing health challenges for many Indigenous Peoples, but also potentially create new challenges, such as coping with ecological grief and anxiety [7], solastalgia and the loss of beloved places [14], and intangible impacts of environmental loss and damage [13].
Much of the existing research on Indigenous experiences of mental health in relation to climate change has involved case studies that examined the locally-and culturally-specific mental health impacts of climate change among Indigenous groups [12,[27][28][29][30]. Given the diverse understandings of mental wellbeing across Indigenous contexts [31] and the geographical variation in climate change exposures [25], there are likely both similarities and differences globally among the Indigenous mental health experiences of climate change. As such, the current study sought to synthesize these understandings with a systematic scoping review of the published literature. Specifically, the goal of this scoping review was to examine the extent, range, and nature of published research investigating the ways in which global Indigenous mental health is impacted by meteorological, seasonal, and climatic changes, and synthesize these findings to offer a more holistic picture of Indigenous mental health in a changing climate.

Methods
The review protocol was developed using a scoping review framework [32], and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses' reporting guidelines for scoping reviews [PRISMA-ScR; 33]. This process included the following steps: (1) identifying the research question and purpose; (2) identifying relevant articles; (3) selecting articles for inclusion; (4) extracting data from included articles; and (5) summarizing, analyzing, and reporting results. The following question guided this review: What is reported in the existing published research about the ways in which Indigenous mental health is impacted by meteorological, seasonal, and climatic variables?Within this broad question, this review sought to specifically answer: What are the publications trends over time and place?What are the pathways through which climate change is currently effecting, and/or anticipated to effect, Indigenous mental health?

Search strategy
Search terms and strings were developed by the research team in consultation with a university librarian and informed by on-going research collaborations, discussions, and continual learning with Indigenous research colleagues, particularly in Northern Canada and Inuit Nunangat, as well as ongoing collaborations with Indigenous colleagues in Uganda and Peru (see table 1 in the supplementary file, Relevance screening was conducted in two stages using inclusion criteria based on study design, content, and year of online publication (table 2): first, titles and abstracts were screened; second, the full texts of potentially relevant articles were screened (see table 2 in the supplementary file for a complete list of screening questions). Articles were independently screened by two reviewers at both stages of screening, where those articles deemed ineligible by both reviewers were excluded. At both stages of screening, the level of agreement between reviewers was assessed using Cohen's Kappa (κ), where κ0.80 indicated excellent agreement [35]. Reviewers met regularly throughout the review to discuss and reconcile any conflicting screening results. Articles were considered to be relevant to this review if: they presented empirical research; humans were the focus or a primary subject; they were published online in 2007 or later (i.e. after the Intergovernmental Panel on Climate Change's (IPCC) Fourth Assessment Report, when more diverse human health and wellbeing impacts of climate change began to be considered [36]); mental health was discussed; meteorological and climatic conditions were discussed; and the articles' authors considered mental health and meteorological and climatic conditions as they relate to each other. Additionally, in the second stage of screening, Indigenous Peoples had to be reported as a population of interest within the article (table 2). In this review, we focus on research with Indigenous Peoples, recognizing them as distinct peoples with specific rights, diverse cultural backgrounds, and diverse approaches to self-determination [37].

Data analysis and synthesis
A data charting form was created and applied in DistillerSR © (see table 3 in the supplementary file). The data charting form served to capture descriptive data on article information (e.g. year of publication, and authors' institutional affiliations) and study characteristics (i.e. primary or secondary research, country of study, geographic scope of study, and methodology). Additionally, information relevant to the scoping review objective was extracted, including: categories of mental health topics relevant in both Indigenous and climate change contexts; how mental health was considered within the context of climate change; and Table 2. Inclusion and exclusion criteria used to identify published articles on the relationship between Indigenous mental health and meteorological, seasonal, and climatic conditions.

Inclusion Exclusion
Empirical research Conference abstracts or proceedings, protocols/frameworks, commentaries, articles in media, editorials, calls for research, literature reviews without a search strategy, letters to the editor, book reviews, textbooks, replies from author, erratum, thesis, or opinion pieces Article discussed meteorological, seasonal, and/or climatic variables in the natural world Meteorological, seasonal a , or climatic conditions in a built or controlled environment (e.g. 'work climate', laboratory or clinical settings, endogenous systems such as body temperature and circadian rhythms), or if the article exclusively discussed geological events b (e.g. earthquake, volcano, etc) Article discussed human mental health and related outcomes Mental health terms used in relation to an inanimate object, or outside the context of human wellbeing (e.g. growth depression, or system stresses) Article explicitly discussed Indigenous Peoples Only non-Indigenous populations Published online on 1 January 2007, or later Published online prior to 1 January 2007 a Articles that only considered seasonality in relation to daylight hours were not included as our objective was concerned with seasonality in meteorological factors (e.g. temperature) that may be directly impacted by climate change. b Articles that exclusively discussed geological events were excluded, as our objective was concerned with meteorological variables directly subject to change from anthropogenic climate change.
how the article reported Indigenous engagement in the research process. Following this descriptive data charting, results were exported into Microsoft ® Excel 2016 (Microsoft Corporation, Redmond, WA, USA) and Stata ® 13.1 (StataCorp, College Station, TX, USA) to visualize and summarize study characteristics. In addition to descriptive data charting, all articles were thematically analyzed using a constant-comparative approach to identify patterns within and across articles, methodologies, and research contexts [38,39]. This qualitative analysis served to identify, characterize, and synthesize important themes and gaps across all articles, and also provided context to information extracted during the data charting stage.

Consultation and engagement
Ongoing engagement and collaboration with Indigenous research partners and leaders guided the conceptualization, analyses, and interpretation of findings for this review. Two co-authors (AC and SLH) have been working with Indigenous Peoples on climate change and mental health community-led research for more than ten years, and this ongoing work continues to inform related research, including this scoping review. Ongoing meetings with Indigenous community members, government representatives, and graduate students also informed the creation and interpretation of this review and assisted in the contextualization of the results.

Search strategy limitations
While this scoping review strategy was comprehensive, there were limitations. First, only published research was examined; gray literature was not reviewed. While gray literature may likely contain a variety of information relevant to mental health and wellbeing programming, policy, and action plans, the purpose of this review was to understand findings and trends in the published literature. Second, while we included non-English articles, the search string was developed in English, and therefore may have limited the ability to identify literature that was not indexed in English.

Results
Searches of the three electronic databases identified 8096 articles after removing duplicates (figure 1). Our search identified articles published in 10 different languages, including English, French, Russian, Spanish, Chinese, Portuguese, Turkish, German, Swedish, and Afrikaans. After screening, 50 articles met all inclusion criteria and underwent full data extraction and analyses (see table 4 in the supplementary file for the complete list of included articles). The level of agreement between reviewers was excellent (κ0. 80). Articles that were relevant and met the inclusion criteria were written in English and Chinese.

What are the publication trends over time and place?
Articles included in this review discussed or reported a variety of Indigenous determinants of mental wellbeing (figure 2) and climatic stressors related to mental health (table 3). Almost all included articles were primary research (n=48/50 articles; 96%), and predominantly used qualitative methods (n=28/50 articles; 56%). The majority of primary research was conducted in Canada (n=19/48 articles; 39.6%), Australia (n=12/48 articles; 25%), or the United States of America (n=5/48 articles; 10.4%; figure 3), and occurred at a local/community level (n=25/48 articles; 52.1%; figure 4) that were predominantly set in remote or rural contexts [e.g. [40][41][42]. The number of articles discussing Indigenous mental health in relation to weather and climate generally increased over time (figure 5).
Indigenous involvement in the research process was reported in 48% of the included articles (n=24/ 50 articles). Of these articles, Indigenous involvement was most often reported in the data collection (n=20/24 articles; 83.3%), study design (n=17/24 articles; 70.8%), and analysis (n=15/24 articles; 62.5%) stages of research. Indigenous engagement was less commonly reported in the study conceptualization (n=12/24 articles; 50%) and writing (n = 7/24 articles; 29.2%) stages of research. Overall, the proportion of articles reporting Indigenous involvement did not appear to increase over time (figure 5), and were reported more commonly within specific co-author networks [e.g. 30, 43, 44].

How does climate change impact Indigenous mental health?
3.2.1. A variety of climate-sensitive mental health outcomes were studied The included articles described a variety of mental health impacts that were linked to acute and extreme weather exposures, chronic and cumulative exposure of multiple weather variables, as well as vicarious and anticipated experiences of climatic stressors. Importantly, mental health impacts and climatic stressors were not exclusive to any one pathway, peoples, or region, and were often overlapping (table 3).
Both qualitative and quantitative research linked acute and short-term weather variables such as storms, flooding, temperature, and seasonality with a range of psychological and mental health impacts including depression and anxiety [e.g. 10, 49, 50], suicide [47][48][49], self-harm [50], post-traumatic stress disorder [PTSD; 51-53], psychological resilience [53], selfreported mood and behavior [54,55], mental illness and behavioral disorders [56], and strong emotional reactions such as fear and anxiety [e.g. 27]. Changes in temperature and precipitation were the most commonly reported weather variables, and often investigated in relation to suicide or self-harm, substance abuse, depression, and stress ( figure 6).
The majority of the included articles reported on the effect of chronic exposure to multiple climatic variables, and/or subacute weather events, and subsequent environmental changes (table 3), which were often linked with emotional responses and feelings of loss, worry, anger, sadness, and ongoing emotional distress (figure 6). These subacute and chronic climatic exposures, including drought, sea ice changes, changes to wildlife and vegetation, and altered seasons were not directly linked to the onset of acute mental and behavioral illnesses such as suicide, depression, and PTSD. Although, several articles and study Figure 2. Proportion of mental health-related topics discussed across articles each year. Note, these topics are not mutually exclusive, such that one article could be counted to cover from one to all 12 topics. populations expressed concern that the cumulative effects of repeated exposure to both acute and chronic climatic stressors, and climate-sensitive drivers of mental health (e.g. food and water insecurity, further discussed below), could manifest in the form of mental illness [e.g. 46,48], an increased use of health services [e.g. 8,44], and maladaptive coping strategies such as substance abuse, and self-harm [e.g. 8,48,57]. For example, Bunun adolescents in Taiwan who had a history of traumatic experiences were more likely to receive a diagnosis of PTSD following a typhoon, and struggle with higher levels of depression, cognition, and social relations [51]. Similarly, forums held with Indigenous Peoples across rural New South Wales (Australia) suggested that communities facing multiyear drought were struggling with increased substance use leading to interpersonal conflict, and suicidality, in addition to strained social and emotional wellbeing [57]. Despite concerns regarding cumulative effects of projected climatic changes, none of the included articles reported on active monitoring or surveillance of mental health among affected Indigenous Peoples.
Articles in this review also highlighted that neither chronic or acute climatic stressors needed to be experienced directly to induce mental health impacts. Several qualitative studies reported vicarious distress among Indigenous participants who feared or empathized for those, particularly those within their social networks such as family and friends, experiencing intense weather or environmental conditions. For example, Inuit women felt anxiety and fear for family and friends' out on the land during stormy conditions [58]. Moreover, many people interviewed shared strong emotional responses such as sadness [e.g. 59], anger [12], and grief [e.g. 57] for anticipated environmental changes they will have to cope with under a rapidly changing climate.
Very few research articles noted potential positive mental health outcomes resulting from exposure to climatic variables (figure 2), although several articles investigating Indigenous mental health following exposure to a typhoon in Taiwan [e.g. 52] and wildfires in Canada [e.g. 27] reported enhanced community cohesion, compassion, and psychological resilience and growth among some individuals. Overall, however, there were no      [45,58,59,62,70], two of which investigated women's wellbeing in the context of seasonal and climate-dependent food security [45,70]. Research also indicated that some emotional responses to climate change differed by gender [12,59]. For example, an Australian study found that 'Aunties' shared more symptoms of solastalgia (i.e. distress and sadness due to environmental change in their home) [59]. Similarly, in a subarctic Inuit community, female respondents reported higher levels of frustration, sadness, fear, anger, helplessness, and distress in response to observed and lived climatic changes [12], and the odds of reporting feeling angry, scared, and frustrated by changes in the environment were significantly higher for women compared to men [44]. Although no articles reported exclusively investigating males, some articles suggested that anxiety [12], suicide [e.g. 48,49], and substance abuse [e.g. 42] were more of a challenge among males. Of particular concern for male mental health was when seasonal and climate-dependent employment (e.g. farming, hunting) were at risk, as climate-related environmental change had important impacts on their land-based identity [e.g. 43].
Age was also discussed in some articles: four primary research articles explicitly focused on youth [30,51,71,72], two of which examined protective factors for Inuit mental wellbeing in Nunatsiavut, Labrador, Canada [30,71]. Articles described the importance of focusing on youth experiences of climate not only because youth mental health experiences can differ from other generations, but also because these experiences are often formative for mental health and wellbeing later in life [51]. Elders and older community members were also identified as a 'vulnerable' group for mental health impacts related to changing climates [66, p 19], as their identities, livelihoods, and wellbeing were often deeply rooted in time spent on the land [e.g. 57]. Notably, Inuit youth participants expressed particular concern for Elders and seniors in their community, acknowledging that the drastic changes they perceived in environment and culture must be felt even more so among older generations [30].

Food security was a common link between climate and mental health
Food security was a pathway through which climate and Indigenous mental health were frequently linked [e.g. 44,45,54,73]. For example, seasonal fluxes in food harvesting were associated with mental health outcomes [e.g. 45, 54, 74], but mental health was also framed as a risk factor for food insecurity [e.g. 42,60,70]. For instance, those struggling with substance abuse may have less disposable income to prevent food shortages following a poor harvest [60] and/or may be excluded from social safety nets of food sharing networks [42]. Several papers reported how the practice of harvesting and sharing traditional food was tied with fulfilling psychological needs at both individual and community levels. For example, the ability to provide food for one's family was reported as a source of positive identity, and the process of harvesting and subsequent food sharing also contributed to stronger social networks [e.g. 43,57].
Climatic changes were reported as impacting Indigenous Peoples access to adequate quantity and quality of food. In the Australian context, chronic drought deteriorated crops and livestock, resulting in loss of livelihoods and subsequent negative mental health outcomes [e.g. 40,57,68]. In the Arctic, changes in sea ice, wildlife, and vegetation due to altered weather patterns compounded existing high rates of food insecurity among Inuit households [e.g. 60], and impacted relationships supported through the sharing of country food [e.g. 43,69,75]. Grief and mourning for climate-related loss of livestock and wildlife was also documented: Sami reindeer herders in Sweden reported loss of animals due to increased climate-driven predation [76,77]; Indigenous Peoples in northern Vietnam experienced the loss of water-buffalo due to changing temperatures [42]; and Inupiat in Alaska experienced an insufficient whale harvest as 'a starvation at emotional and spiritual levels' [69, p 296].

Climate-induced human mobility was a mental health concern
The mental health implications of human mobility (i.e. migration and displacement) were also discussed in many articles. Climatic change and resultant environmental impacts, such as sea level rise and chronic drought, may alter landscapes to such an extent that they are no longer able to support Indigenous cultures and livelihoods in the same way [e.g. 65,67]. For example, forced out-migration was either suggested or documented for Indigenous Peoples in both Australia [40,68] and Tanzania [73] due to loss of farming livelihoods following prolonged drought.
Mental health concerns resulting from unplanned relocation following extreme, acute weather events were also reported. For example, in the year following a typhoon in Taiwan, individuals who were able to stay in their community showed higher resilience compared to those who relocated to urban centers [53]. Furthermore, poor planning and policy had more severe psychological consequences than the disaster itself; as such, 'governments should set aside more space, hold longer discussions, and provide different alternatives' for relocation [53, p109].
Of note, only two articles specifically asked participants about planned relocation due to environmental changes as an adaptation strategy [12,65]. For example, over 90% of Inuit who were surveyed in the community of Rigolet, Nunatsiavut, Labrador, Canada, indicated they would not leave their community due to climatic and environmental changes [12]. Similarly, the Inupiat community of Shishmaref, Alaska, USA, were also resistant to planned relocation due to rising sea levels, ongoing flooding, and six state-declared disasters since 1988, where the potential trauma of loss of meaningful places, social networks, and culture was reported to be of great concern [65, p 419]: In a place where the risks of death and material destruction are very real possibilities in the event of a large storm and flooding event, ethnographic accounts demonstrate that residents discuss these immediate risks less frequently than the long-term psychological and cultural ramifications of relocating the entire communityK.
While community members largely agree that relocating is necessary, they believe that remaining in culturally significant rural areas is paramount to long-term, successful adaptation.
3.2.6. Climate change compounds emotions tied to historical and ongoing disempowerment Helplessness [e.g. 12, 78] and anger were commonly reported across articles as participants lamented their limited ability to mitigate global climate change [e.g. 64] and, in some cases, were linked in the research to feelings of abandonment by governments and the broader global community [65,76,79]. The urgent need to adapt to and/or mitigate climate changes also resurfaced previous traumas for some Indigenous Peoples. For example, Sami reindeer herders in one study likened climate change to the Chernobyl disaster, where 'interviewees described feelings of being alone, powerless and left to fend for themselves after what happened and they had to deal with the problems caused by other people' [76]. A similar finding was reported among Nunatsiavut Inuit in Labrador, Canada, as an Inuit harvester shared [8, p 264]: a lot of trauma that you face-whether it be rape or residential schools or child abuse or anything like that-usually if you are able to find some sense of worth in yourself and value you are able to start unconsciously healing from those wounds or you are able to get enough confidence in yourself to really address them. K If you take away an internal capability and what makes you feel productive, then those tragedies or that past is still there, and then theyʼre magnified because they come more to the surface because youʼre not feeling that personal strength. I think if [climate change] take[s] away those [land] activities and people feel less capable, less able to provide, and less healthy about themselves, then those [mental and emotional] impacts will either come more to the forefront and have to be dealt with or they may just be built upon. KI think that those effects [from trauma of residential schools and assimilation] will be felt further if climate change affects [land] activity.
Related to feelings of helplessness and lack of control, several articles discussed the impacts of a changing climate on Indigenous autonomy and selfdetermination [e.g. 28,43]. For example, Inuit in Nain, Nunatsiavut, Labrador, Canada, associated sea ice with freedom, which means that rapid sea ice loss limits peoples' ability for self-determination, such that climate change was framed as a driver of 'environmental dispossession' [28, p25]. Related to self-determination in the context of climate change, many articles discussed the need for increased Indigenous engagement in climate change policy and relevant programing, and argued that it would likely improve adaptation efforts [e.g. 29].

Discussion
This scoping review synthesized published research to identify global considerations for Indigenous mental health in relation to climate change and, in so doing, highlighted a diversity of pathways through which climate and weather impacts Indigenous Peoples' mental wellbeing. While the variety of study designs and methodologies in the included literature, as well as limited research at regional and national scopes, make it difficult to draw broad conclusions regarding patterns of specific mental health impacts and climatic stressors, similar to the broader literature on climate and mental health [11,24], this scoping review indicates that the onset and type of mental health impacts may be tied to the timing and intensity of climatic exposures. Acute and extreme weather, for example, were linked with a range of psychological and behavioral struggles, such as post-traumatic stress disorder [51][52][53], depression [51,53], suicide and selfharm [47,48,50], and seasonal fluctuations in mood [54], depression [45], and trauma mortality [49]. Importantly, much of the literature in this scoping review reported on how culminative exposure of increasingly unpredictable and intense weather patterns were associated with individual level distress. For example, research in Arctic and Subarctic regions commonly listed the interaction of changes in sea ice, wind, precipitation, and storms as important variables to land access and thereby for emotional and mental wellbeing [41,43,44,61,66,70,80]. Additionally, indirect experiences of climatic stressors produced emotional distress either vicariously or in anticipation of climatic projections that threaten individuals' and communities' futures. Moreover, articles in the present review suggest that emotional and behavioral distress from repeated exposure to multiple climatic stressors and subsequent environmental adversities over time, may be precursors to mental illness, suicidality, substance abuse, and limited psychological resilience [e.g. 8,53]. This is of note since the literature in this review indicated that it is often the subtle, cumulative, non-clinical mental health impacts that are widespread among Indigenous Peoples and communities (see table 3), and thus, may present potentially far-reaching and complex consequences within a continually changing climate.
Interestingly, very little of the included research articles were population-level studies [e.g. 48,49] or came from the disaster-based literature [27,[51][52][53], which have historically linked prevalence and incidence of specific mental illnesses with extreme heat events [16,81], humidity [82], flooding [83], wildfires [84], and hurricanes [85], among other acute climatic stressors across the globe [5]. Few studies in the present review used metrics of mental health and/or climate that are comparable across populations [e.g. 12,47,51]. Rather, the majority of articles were local or regional case studies, which explored more holistic concepts of mental health in depth, and Indigenous Peoples' emotional and behavioral responses to changes in the environment, and the social, cultural, and economic implications of those changes, such as loss of wildlife, livelihoods, and food security. This represents an important gap in the literature on climate-sensitive Indigenous mental health globally, and highlights the need for additional population-level studies.
Only more recently has the broader literature on climate change and mental health begun to quantitatively link subacute weather events with mental health outcomes [5,86]. As such, even globally the implications of repeated and cumulative exposure on individuals' and communities' mental health remains unclear. While some of the research included in the present review linked measures of depression and anxiety with seasonality [45,54] and drought [46], there was otherwise no quantitative evidence of subacute weather and associated environmental events (e.g. heatwaves, and delayed sea ice freeze-up) in the present review. Recent research suggests that factors such as length and intensity of exposure to extreme weather, including drought [87] and extreme temperature [4,19], are important to consider. Notably, there are limited studies projecting mental health under future global climate change scenarios [4], further highlighting the need for more population-level and longitudinal studies examining the mental health impacts of climate change [88].
Despite limited understanding of populationlevel, and longitudinal patterns of climatic stressors and mental health, it appears that different climatic stressors affects Indigenous Peoples differentially. Research examining climate-mental health experiences in Indigenous contexts identified potentially gendered and age-specific mental health outcomes and coping strategies [e.g. 30,57,59,62]. This theme aligns with the broader mental health literature, where mental health outcomes such as suicide and depression, are known to vary by sex and age [89,90]. Notably, climate change research and reports often identify women, children, and the elderly as vulnerable groups for climate-sensitive health outcomes [26]; however, the articles from the present review suggest that Indigenous adults, particularly those with land-based livelihoods, also face specific mental health challenges [e.g. 8,42,60,77]. Similar findings have been found in research from farming contexts in India and Australia, where drought is driving deterioration of farming livelihoods, leading to struggles with suicide and depression [15,19]. Articles in the present review identified differences in coping methods and access to social networks across gender and age groups, suggesting that intersectional approaches to mental health programming and support is important alongside individuallevel resources and those that address community wellbeing more broadly [11,45,57].
The articles reviewed emphasized the importance of the concept of connection to place and its centrality in protecting and enhancing Indigenous mental wellbeing and supporting livelihoods, culture, social structures, and identity [e.g. 1,41]. The importance of place attachment is consistent with findings from the broader Indigenous mental health literature, where a secure sense of place and land-based wellness programming have been linked to improved physical and mental health outcomes among Indigenous Peoples, regardless of urban or rural status [91][92][93][94]. As articles in this review identified, however, both the slow and sudden onset of climate-related changes are disrupting, and in some cases severing, Indigenous Peoples' connections to place [43,65,69]. Researchers have begun to frame these deteriorating connections as another form of environmental dispossession [28,95,96], as well as a human rights issue within climate justice discussions [97,98]. Importantly, as climate change progressively impacts place and health, it is unclear how these climateinduced emotional and mental stressors may interact with concurrent health concerns and pre-existing mental illness [99], and possibly compound already-present health concerns [86]. Given the importance of place for mental wellbeing identified in this review, preserving connection to place has been highlighted as an important mental health adaptation for Indigenous Peoples in the context of climate change [11,12,65].
Research also highlighted increasing concern related to forced migration and displacement due to drought [40,73], sea level rise [e.g. 65,69], and environmental degradation [46]. Migration and displacement as an adaptation strategy is contested, given that it is often forced upon peoples when irrevocable loss and damage means that local adaptation is no longer an option [100][101][102]. Importantly, articles in the current review suggested that Indigenous communities do not perceive relocation and migration as desirable adaptation options [12,65]. Climate-driven human mobility is particularly complicated for Indigenous Peoples, as it may resurface past traumas related to forced relocation and displacement, all while meaningful places and associated protective mental wellbeing factors are altered [8,28,103]. Moreover, forced human migration is linked to higher rates of mental illness and substance abuse [104] in conjunction with the loss of critical social support systems [73,105]. This literature makes clear: as unstable and extreme climatic conditions will likely increase the need for climate-driven human mobility, it is important to consider and support the complex mental health needs of Indigenous migrants who may experience disruptions to health-sustaining cultural, social, familial, and environmental networks [65,106].
The deterioration of protective factors for community-wellbeing, such as local cultures and knowledge systems, and the subsequent emotional and mental impacts are examples of intangible (non-economic) climate-induced losses and damages [13,107,108]. These less visible forms of harm were widespread across Indigenous mental health and climate research [1,77,107]; however, as a relatively under-explored topic in global climate justice discussions [109], explicitly describing intangible loss and damage is integral for Indigenous communities to receive appropriate support [13,109]. Yet, in a recent review of intangible harm, less research was reported among Indigenous Peoples in low-income countries; this lack of research was cited as an epistemological disparity in which forms of loss and damage are not being acknowledged, or are absent from the literature, leading to important and inequitable gaps in understanding [107].
Although understandings of the inequitable and diverse mental health impacts of climate change have expanded over the last decade, only recently have these intangible forms of loss and damage been recognized by international scientific bodies leading the calls for action on climate change [25]. Notably, recent updates to the United Nations' Paris Agreement have called for a place for nations to systematically report their intangible losses and damages alongside climate change interventions within the transparency framework [110]. Existing loss and damage tracking systems, such as insurance databases, are ill-suited or incapable of documenting intangible climate-driven impacts [111]. Evidence shows that the application of diverse methodological approaches [13,109] and increased engagement with Indigenous communities [112] will be necessary to document these intangible losses and damages, determine the potential limits of adaptation, and propose desirable alternative pathways.

Conclusion
Since the IPCC's Fourth Assessment Report [36], burgeoning research has advanced our understanding of current and future impacts of climate change on Indigenous mental health [e.g. 113]. By synthesizing the published research relevant to Indigenous mental health and climate change, this scoping review has highlighted the multifaceted ways in which climate links to the mental wellbeing of Indigenous Peoples globally, the already widespread climate-driven mental and emotional impacts, as well as identified important opportunities to support Indigenous mental wellbeing within a changing climate. As Indigenous Peoples face a rapidly changing environment, this literature review indicates that acute mental health impacts can arise while existing mental health struggles are often exacerbated, and intangible losses and damages will continue to create new mental health challenges. In recognizing the highly interconnected and potentially pervasive mental health challenges Indigenous Peoples will face, there exist important opportunities for global research efforts to engage Indigenous Peoples on this topic, while building upon existing causal understandings to better plan and prepare for the mental health implications of rapid climatic change.