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Abstract In 2023, the first Polar Postdoc Leadership Workshop convened to discuss present and future polar science issues and to develop leadership skills. The workshop discussions fostered a collective commitment to inclusive leadership within the polar science community among all participants. Here, we outline challenges encountered by underrepresented groups in polar sciences, while also noting that progress has been made to improve inclusivity in the field. Further, we highlight the inclusive leadership principles identified by workshop participants to bring to the polar community as we transition into leadership roles. Finally, insights and practical knowledge we gained from the workshop are shared, aiming to inform the community of our commitment to inclusive leadership and encourage the polar community to join us in pursuing action toward our shared vision for a more welcoming polar science future. 

Abstract A widely examined predictive model of invertebrate community dynamics in glacial‐melt streams describes longitudinal changes in community structure with changing water temperature and channel stability with increasing distance from glaciers. Previous studies conducted in Europe, Greenland, New Zealand, and South America have supported the predictions of the invertebrate model and contributed to its refinement. However, none has evaluated if the model fits invertebrate community dynamics over a full range of distances from the glacier and water temperature conditions within glacial‐melt streams in southeast Tibet.We sampled invertebrates and measured water temperature, specific conductivity, turbidity, and associated glacier‐related variables within 14 sites in three subalpine glacial‐melt catchments in southeastern Tibet's Three Parallel Rivers region during 2010, 2011, 2013, and 2015. Our sites encompassed a temperature gradient from the upstream metakryal sites (maximum summer water temperature <2°C) to the furthest downstream site (maximum summer temperature >10°C) near the Mekong River.We evaluated the relationships of invertebrate community structure with in situ water temperature and channel stability which are the focal habitat variables in the invertebrate model. The additional habitat variables of distance from the glacier, glacier size, conductivity, and turbidity were evaluated to see if these were more important determinants of community structure than in situ water temperature and channel stability.Minimum and in situ water temperatures were positively correlated with distance from the glacier but Pfankuch Channel Stability Index bottom scores were not. Thus, the physical template within our study area differed from the expected template of the invertebrate model.Similar to the invertebrate model, in situ water temperature by itself or combined with Pfankuch index best explained five invertebrate response variables. In contrast with the invertebrate model, conductivity and turbidity best explained invertebrate taxa richness, density, and the site scores of the first and second detrended correspondence analysis axes of relative abundance.The invertebrate model predicts that only Diamesinae will occur in metakryal sites. However, in our metakryal sites we frequently captured 13 taxa (two Nemouridae morphotypes, Diamesinae, Orthocladiinae,Rhyacophila,Epeorus, Taeniopterygidae,Baetis,Capnia, Simuliidae, Limnephilidae,Himalopsyche, and Collembola).Invertebrate‐habitat relationships and taxa occurrence trends in glacial‐melt catchments in southeast Tibet differed from the invertebrate model predictions. Our findings highlight the need to develop a regional version of the invertebrate model applicable to Asian glacial‐melt streams with unstable stream channels throughout their catchments and that do not freeze in the winter. 

Abstract Supraglacial pools are prevalent on debris-covered mountain glaciers, yet only limited information is available on the microbial communities within these habitats. Our research questions for this preliminary study were: (1) What microbes occur in supraglacial pool sediments of monsoonal Tibet?; (2) Which abiotic and biotic habitat variables have the most influence on the microbial community structure?; and (3) Does microbial composition of supraglacial pool sediments differ from that of glacial-melt stream pool sediments? We collected microbial samples for 16S rRNA sequencing and invertebrates for enumeration and identification and measured 14 abiotic variables from 46 supraglacial pools and nine glacial-melt stream pools in 2018 and 2019. Generalized linear model analyses, small sample Akaike information criterion, and variable importance scores were used to identify the best predictor variables of microbial community structure. Multi-response permutation procedure (MRPP) was used to compare taxa composition between supraglacial pools and stream pools. The most abundant phyla in supraglacial pool sediments were Proteobacteria, Actinobacteria, Bacteroidota, Chloroflexi, and Cyanobacteria. Genera richness, indicator genera richness, andPolaromonasrelative abundance were best predicted by Chironomidae larvae abundance. 

Debris-covered glaciers (DCGs) are globally distributed and thought to contain greater microbial diversity than clean surface continental glaciers, but the ecological characteristics of microbial communities on the surface of DCGs have remained underexplored. Here, we investigated bacterial and fungal diversity and co-occurrence networks on the supraglacial debris habitat of two DCGs (Hailuogou and Dagongba Glaciers) in the southeastern Tibetan Plateau. We found that the supraglacial debris harbored abundant microbes with Proteobacteria occupying more than half (51.5%) of the total bacteria operational taxonomic units. The composition, diversity, and co-occurrence networks of both bacterial and fungal communities in the debris were significantly different between Hailuogou Glacier and Dagongba Glacier even though the glaciers are geographically adjacent within the same mountain range. Bacteria were more diverse in the debris of the Dagongba Glacier, where a lower surface velocity and thicker debris layer allowed the supraglacial debris to continuously weather and accumulate nutrients. Fungi were more diverse in the debris of the Hailuogou Glacier, which experiences a wetter monsoonal climate, is richer in calcium, has greater debris instability, and greater ice velocity than the Dagongba Glacier. These factors may provide ideal conditions for the dispersal and propagation of fungi spores on the Hailuogou Glacier. In addition, we found an obvious gradient of bacterial diversity along the supraglacial debris transect on the Hailuogou Glacier. Bacterial diversity was lower where debris cover was thin and scattered and became more diverse near the glacial terminus in thick, slow-moving debris. No such increasing bacterial pattern was detected on the Dagongba Glacier, which implies a positive relationship of debris age, thickness, and weathering on bacterial diversity. Additionally, a highly connected bacterial co-occurrence network with low modularity was found in the debris of the Hailuogou Glacier. In contrast, debris from the Dagongba Glacier exhibited less connected but more modularized co-occurrence networks of both bacterial and fungal communities. These findings indicate that less disturbed supraglacial debris conditions are crucial for microbes to form stable communities on DCGs.