Climatic Change最新文献

The special reports of the Intergovernmental Panel on Climate Change (IPCC) have a unique character in IPCC scientific assessment. Their main purpose is to address specific timely issues of policy relevance. This article explores the nature and role of IPCC special reports along the lines of three questions: (1) the history (‘where they come from’); (2) the function (‘what they are doing’); and (3) the future (‘where they are going’). In earlier assessment cycles, special reports were characterised mostly as a direct channel for quickly responding to the request from the United Nations Framework Convention on Climate Change (UNFCCC). The conduct of special reports has been gradually institutionalised to embed its planning in the overall scoping of the entire assessment cycle. More recently, they have become a vehicle to consolidate cross-cutting scientific perspectives and serve the diverse needs of the international policy community, not only the UNFCCC. This historical evolution is, in a sense, the result of striving for greater policy relevance. Special reports have a dual political function—namely, turning into the site or object of politicised debates on science (politicisation) and serving as ‘de facto governance’ with the effect of normalising politically contested ideas (normalisation). This dual function is two different faces emerging from the process into which the IPCC is brought to deal with political controversy. The duality of the two functions also manifests inherent tensions that lie behind the IPCC’s ‘policy-relevant but not policy-prescriptive’ principle. For the future of special reports, the IPCC could reconsider the role of special reports in light of the priority over comprehensive assessment reports, the responsiveness to the UNFCCC request and the selection and scope definition of timely topics. However, there will remain a trade-off between provisional science and lasting political impact caused by the future undertaking of IPCC special reports on any topic.

Snowdrifts on lake ice provide vital breeding habitats for the endangered Saimaa ringed seal. In this study, a lake ice model of Watershed Simulation and Forecasting System (WSFS-Ice) was developed for improved estimation of ice and snow conditions in Lake Saimaa during the pupping season of the Saimaa ringed seal. The WSFS-Ice model is based on energy balance, enabling reliable estimation of the ice cover evolution in current and future climate. In addition, a simple snowdrift model was used to simulate formation of snowdrifts, which are essential for the seals breeding success in Lake Saimaa. The model was calibrated against ice thickness, ice type and snow depth measurements. According to our results based on climate scenarios with intermediate representative concentration pathway (RCP4.5), the breeding habitat of the Saimaa ringed seal is significantly deteriorating during the twenty-first century. The mean depth of the snowdrifts is projected to decrease approximately to half from the 1981–2010 to 2070–99 period and at the same time the ice-covered period is reduced by one and a half months. During the mildest winters the ice cover is projected to melt even before the pupping season has ended. The results highlight the importance of climate change mitigation and active conservation measures to enhance seal population growth, enabling it to survive in a changing climate.

Climate adaptation for Indigenous communities is not as simple as making good policy; it is equally about how policy is implemented and how collaboration unfolds between settler governments and Indigenous stakeholders. Rural Alaska Native villages are among the most environmentally threatened communities in the United States. Their ability to effectively manage environmental change and preserve sovereignty depends upon successful collaboration with a range of stakeholders, especially federal agencies. For more than two decades, academics and government agencies have documented a consistent pattern of failures, particularly by federal actors, to effectively manage adaptation challenges. These obstacles are sometimes misrepresented as policy failures. While poor policy is certainly involved in these poor outcomes, this paper highlights a set of barriers to successful collaboration that are not policy issues, per se, but rather micropolitical issues; that is, they pertain to the conduct of government in the context of Tribal relationships. Unaddressed, these micropolitical issues have created obstacles to Alaska Native communities’ self-determination as they adapt to a changing landscape. These barriers are explored in a case study drawn from Typhoon Merbok, which struck Western Alaska in 2022, and empirically grounded in a series of interviews and participant observation with experts, elders, elected officials, and Tribal staff. This article concludes with several concrete recommendations to improve the practice of domestic diplomacy between Indigenous communities and colonial governments.

Capacity building is recognized as one of three means of implementation (MOI) within the Paris Agreement, along with finance and technology. There is a good reason for this, namely that all aspects of climate action require multiple forms of capacity. In fact, it could be argued that capacity is foundational even to the other two MOIs as advancing both finance and technology requires a variety of capacities across multiple specific contexts. The Global Stocktake (GST) recognized the importance of capacity building for the achievement of the Paris Agreement and included its assessment within its evaluation of progress. However, unlike the other two MOIs, no chapter within the IPCC AR6 explicitly attempts to synthesize the state of knowledge about capacity or capacity building for climate action, and coverage of capacity remains scattered across the report. In this commentary we briefly reflect on the coverage of capacity and capacity building in the IPCC’s AR6 and develop some initial proposals for how knowledge about this key MOI could be better included in future assessment processes.

The Covid-19 pandemic challenged global governance in unprecedented ways by requiring intergovernmental meetings to be held online. For the Intergovernmental Panel on Climate Change (IPCC), this meant that the intergovernmental approval of the key findings of the Sixth Assessment Report (AR6) had to be conducted virtually. In this paper, we assess how the move away from face-to-face meetings affected country participation in IPCC approval sessions. Our findings demonstrate that virtual meetings increased the size of member governments’ delegations, but this did not necessarily translate into a greater number of interventions during the approval of the Summary for Policymakers (SPM) as time zone differences reduced engagement levels significantly—particularly for countries from the Pacific, East Asian, and Latin American regions whose delegations often found themselves in IPCC meetings late at night and early in the morning. These results offer initial, empirically robust evidence about what online meetings can and cannot achieve for promoting more inclusive global governance at a time when the IPCC and other organizations reflect on the future use of virtual and hybrid meeting formats.

The Tibetan Plateau (TP), the Third Pole of the world, has experienced significant warming over the past several decades. Previous studies have mostly relied on station-observed air temperature (T_a), reanalysis data, and remotely sensed land surface temperature (LST) to analyze the warming trend over the TP. However, the uneven distribution of stations, the poor spatial resolution of reanalysis data, and the differences between LST and T_a may lead to biased warming rates. This paper first maps T_a over the TP from 2001 to 2020 based on multi-source remote sensing data, and then quantifies the spatio-temporal variations of remotely sensed T_a and elevation dependent warming (EDW) of this region. The monthly mean T_a is estimated using machine learning (ML) method year by year, and its accuracy is validated based on station-observed T_a. The coefficient of determination (R² ranges from 0.97 to 0.98 and the mean absolute error (MAE) ranges from 1.01 to1.04 °C. The remotely sensed T_a is used to analysis warming trend and EDW over the TP. The overall warming trend of the TP during 2001–2020 is 0.17 ℃/10a, and warming mainly distributed in the eastern TP, central TP and western Kunlun Mountains. Among the four seasons, autumn shows the most significant warming, tripling the annual warming rate. Winter shows a significant cooling trend, with the warming rate of -0.18 ℃/10a. The study also reveales the existence of EDW at both the annual and seasonal scales. This paper suggests the potential of remotely sensed T_a in global warming study, and also provides an improved understanding of climate warming over the TP.

The terms “global warming,” “climate crisis,” “climate emergency,” and “climate justice” each draw attention to different aspects of climate change. Psychological theories of attitude formation suggest that people’s attitudes can be influenced by such variations in terminology. In a national experiment, we randomly assigned a national sample of 5,137 U.S. residents to “climate change,” “global warming,” “climate crisis,” “climate emergency,” or “climate justice” and examined their responses. Overall, “climate change” and “global warming” were rated as most familiar and most concerning, and “climate justice” the least, with ratings for “climate crisis” and “climate emergency” falling in between. Moreover, we find no evidence for “climate crisis” or “climate emergency” eliciting more perceived urgency than “climate change” or “global warming.” Rated willingness to support climate-friendly policies and eat less red meat were less affected by presented terms, but they were lowest for “climate justice.” Although effects of terms on rated familiarity, concern, and perceived urgency varied by political leaning, “climate justice” generally received the lowest ratings on these variables among Democrats, Republicans, and Independent/others. Auxiliary analyses found that when terms were unfamiliar, participants were generally less likely to express concern, urgency, policy support, or willingness to eat less red meat. We therefore recommend sticking with familiar terms, conclude that changing terminology is likely not the key solution for promoting climate action, and suggest alternative communication strategies.

Removing greenhouse gases from the atmosphere is a major challenge for today’s society. A great source of potential for greenhouse gas sequestration is beneath our feet: agricultural soil. By accumulating soil organic carbon in soil, farmers can sequester carbon dioxide and simultaneously reach soils more resilient to extreme weather events. To encourage farmers to build up humus and thus sequester carbon, some humus programmes have been developed by non-governmental organisations. In this regard, action-based reward systems are on their way to challenging the established results-based approaches. Against this background, we analyse how action-based and results-based approaches, as well as other crucial features of humus programmes, affect farmers’ willingness to participate in a humus programme. We conducted a Discrete-Choice-Experiment and analysed it using a mixed logit model. The results show that farmers have a statistically significant preference for action-based humus programmes, shorter programme durations, higher incentives, and an annual and government-funded payment. More specifically, farmer participation is twice as likely if humus formation is rewarded for action rather than results. The willingness-to-accept calculation indicates that a results-based humus programme would cost the funding agency about €20 more per ton of carbon dioxide sequestered in the soil. Above all, humus programmes with an action-based approach and annual payments would increase farmers’ willingness to participate. Our results contribute to the development of targeted humus programmes and policies to increase carbon sequestration in agricultural soils.

Climate change distress has been shown to be associated with markers of negative mental health. However, it is unclear whether climate change distress is also associated with suicidal ideation and whether this association might be mediated by perceptions of entrapment. On this background, the purpose of the present study was to investigate the association between climate change distress/impairment, entrapment, and suicidal ideation. Participants were recruited at a university in the Ruhr region in Germany. Overall, 323 participants (68.4% female; M_age=26.14, SD_age=8.35, range: 18–63 years) filled out self-report questionnaires on climate change distress/impairment, entrapment, and suicidal ideation online. Climate change distress/impairment was significantly positively associated with suicidal ideation. Entrapment completely mediated the association between climate change distress/impairment and suicidal ideation. Results underlines how stressful and existential climate change is experienced by many young persons. Findings underscore the need to develop and evaluate interventions to target climate change distress/impairment.