e2024GL111434 2024GL111434
", "tags": [], "relations": {}, "dateAdded": "2026-10-23T17:44:35Z", "dateModified": "2026-10-23T17:44:35Z" } }, { "key": "IC4T57R6", "version": 1144, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/IC4T57R6", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/IC4T57R6", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Geller et al.", "parsedDate": "2026-12-01", "numChildren": 0 }, "data": { "key": "IC4T57R6", "version": 1144, "itemType": "journalArticle", "title": "Modeled variations in transport and export of riverine freshwater across a chain of Beaufort Sea lagoons for a range of open water season conditions", "creators": [ { "creatorType": "author", "firstName": "Tina", "lastName": "Geller" }, { "creatorType": "author", "firstName": "Julia M.", "lastName": "Moriarty" }, { "creatorType": "author", "firstName": "Irina", "lastName": "Overeem" }, { "creatorType": "author", "firstName": "Yvette H.", "lastName": "Spitz" }, { "creatorType": "author", "firstName": "Melissa", "lastName": "Moulton" } ], "abstractNote": "The transport and retention of freshwater in estuaries affect habitat, water quality, and biogeochemical cycles. This study implemented a numerical hydrodynamic and particle tracking model to understand the variability in freshwater transport and retention in the Kaktovik Lagoon chain, a series of connected Beaufort Sea back-barrier estuaries in Arctic Alaska. Specifically, the Regional Ocean Modeling System (ROMS) was implemented for the peak open water season of 2019. Salinity and the transport of Lagrangian tracers released at river mouths were analyzed during six periods over late July into September, characterized by different winds, shelf currents, and river discharge. Modeled lagoon currents and freshwater transport oscillated primarily in the along-shore direction, consistent with east-west winds and shelf currents. Across the lagoon chain, freshwater was preferentially retained in more protected lagoons and in deeper regions of the estuary, whereas lagoons with greater connectivity to the shelf experienced more rapid loss to other regions of the chain or export to the shelf. Depending on winds, shelf currents, and river discharge, about 30-87% of the total freshwater tracers were exported from the lagoon chain within three days, with the fastest export during periods of westward transport. Uncertainties in forcings condition the results, with river-discharge uncertainty alone altering export by up to ∼10% and half-life by up to ∼2.4 days. Despite this uncertainty, the results demonstrate that freshwater retention is favored in more protected and deeper regions and when winds and shelf currents are weak.", "publicationTitle": "Continental Shelf Research", "publisher": "", "place": "", "date": "2026-12-01", "volume": "303", "issue": "", "section": "", "partNumber": "", "partTitle": "", "pages": "105797", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Continental Shelf Research", "DOI": "10.1016/j.csr.2026.105797", "citationKey": "", "url": "https://www.sciencedirect.com/science/article/pii/S0278434326001603", "accessDate": "2026-10-22T16:10:42Z", "PMID": "", "PMCID": "", "ISSN": "0278-4343", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "", "libraryCatalog": "ScienceDirect", "callNumber": "", "rights": "", "extra": "https://doi.org/10.6073/pasta/91bf4e756e81fbde485ff36aa97827d5", "tags": [ { "tag": "Arctic", "type": 1 }, { "tag": "Estuaries", "type": 1 }, { "tag": "Export", "type": 1 }, { "tag": "Freshwater", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "Numerical hydrodynamic modeling", "type": 1 }, { "tag": "Retention", "type": 1 }, { "tag": "Supported" }, { "tag": "Transport", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-10-22T16:10:42Z", "dateModified": "2026-10-22T16:12:43Z" } }, { "key": "A2XP3E9L", "version": 1139, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/A2XP3E9L", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/A2XP3E9L", "type": "text/html" } }, "meta": { "createdByUser": { "id": 5767825, "username": "atn38", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/atn38", "type": "text/html" } } }, "lastModifiedByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Baker et al.", "parsedDate": "2021", "numChildren": 0 }, "data": { "key": "A2XP3E9L", "version": 1139, "itemType": "journalArticle", "title": "The Genomic Capabilities of Microbial Communities Track Seasonal Variation in Environmental Conditions of Arctic Lagoons", "creators": [ { "creatorType": "author", "firstName": "Kristina D.", "lastName": "Baker" }, { "creatorType": "author", "firstName": "Colleen T. E.", "lastName": "Kellogg" }, { "creatorType": "author", "firstName": "James W.", "lastName": "McClelland" }, { "creatorType": "author", "firstName": "Kenneth H.", "lastName": "Dunton" }, { "creatorType": "author", "firstName": "Byron C.", "lastName": "Crump" } ], "abstractNote": "In contrast to temperate systems, Arctic lagoons that span the Alaska Beaufort Sea coast face extreme seasonality. Nine months of ice cover up to ~1.7 m thick is followed by a spring thaw that introduces an enormous pulse of freshwater, nutrients, and organic matter into these lagoons over a relatively brief 2-3-week period. Prokaryotic communities link these subsidies to lagoon food webs through nutrient uptake, heterotrophic production, and other biogeochemical processes, but little is known about how the genomic capabilities of these communities respond to seasonal variability. Replicate water samples from two lagoons and one coastal site near Kaktovik, AK were collected in April (full ice cover), June (ice break up), and August (open water) to represent winter, spring, and summer respectively. Samples were size fractionated to distinguish free-living and particle-attached microbial communities. Multivariate analysis of metagenomes indicated that seasonal variability in gene abundances was greater than variability between size fractions and sites, and that June differed significantly from the other months. Spring (June) gene abundances reflected the high input of watershed-sourced nutrients and organic matter via spring thaw, featuring indicator genes for denitrification possibly linked to greater organic carbon availability, and genes for processing phytoplankton-derived organic matter associated with spring blooms. Summer featured fewer indicator genes, but had increased abundances of anoxygenic photosynthesis genes, possibly associated with elevated light availability. Winter (April) gene abundances suggested low energy inputs and autotrophic bacterial metabolism, featuring indicator genes for chemoautotrophic carbon fixation, methane metabolism, and nitrification. Winter indicator genes for nitrification belonged to Thaumarchaeota and Nitrosomonadales, suggesting these organisms play an important role in oxidizing ammonium during the under-ice period. This study shows that high latitude estuarine microbial assemblages shift metabolic capabilities as they change phylogenetic composition between these extreme seasons, providing evidence that these communities may be resilient to large hydrological events in a rapidly changing Arctic.", "publicationTitle": "Frontiers in Microbiology", "publisher": "", "place": "", "date": "2021", "volume": "12", "issue": "", "section": "", "partNumber": "", "partTitle": "", "pages": "", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Front. Microbiol.", "DOI": "10.3389/fmicb.2021.601901", "citationKey": "", "url": "https://www.frontiersin.org/articles/10.3389/fmicb.2021.601901/full", "accessDate": "2021-03-15T13:29:00Z", "PMID": "", "PMCID": "", "ISSN": "1664-302X", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "English", "libraryCatalog": "Frontiers", "callNumber": "", "rights": "", "extra": "https://doi.org/10.6073/pasta/6bfe32f7eb95a886ee5af8f099634b3c\nhttps://doi.org/10.6073/pasta/9acb5a6f3956476be643e88c403404e3\nhttps://doi.org/10.6073/pasta/4dcefec5d550301065619ed15b2192cc", "tags": [ { "tag": "Archaea", "type": 1 }, { "tag": "Arctic", "type": 1 }, { "tag": "Arctic National Wildlife Refuge (ANWR)", "type": 1 }, { "tag": "Bacteria", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "LTER-Funded" }, { "tag": "Supported" }, { "tag": "estuary", "type": 1 }, { "tag": "omics", "type": 1 }, { "tag": "sea ice", "type": 1 } ], "collections": [ "C3XB5ABB", "IJ4K8DFH", "KHTHLKB5", "ZQZ83R7H" ], "relations": {}, "dateAdded": "2021-03-15T13:29:00Z", "dateModified": "2026-10-21T16:59:26Z" } }, { "key": "QDXLF85H", "version": 1138, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/QDXLF85H", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/QDXLF85H", "type": "text/html" } }, "meta": { "createdByUser": { "id": 5767825, "username": "atn38", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/atn38", "type": "text/html" } } }, "lastModifiedByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Bonsell and Dunton", "parsedDate": "2021", "numChildren": 0 }, "data": { "key": "QDXLF85H", "version": 1138, "itemType": "journalArticle", "title": "Slow Community Development Enhances Abiotic Limitation of Benthic Community Structure in a High Arctic Kelp Bed", "creators": [ { "creatorType": "author", "firstName": "Christina", "lastName": "Bonsell" }, { "creatorType": "author", "firstName": "Kenneth H.", "lastName": "Dunton" } ], "abstractNote": "Seasonal hydrographic fluctuations may impart strong abiotic control on community structure in nearshore Arctic ecosystems, but the effects may be overcome by propagule delivery and recruitment. We compared spatial differences in benthic community structure to environmental factors (temperature, salinity, current speed, underwater light) and static habitat attributes (depth, distance from river inputs) in a shallow High Arctic kelp bed in the Beaufort Sea. Spatial and temporal patterns of recruitment and community development were observed to assess the timescale and trajectory of community development. Foliose red algae (47-79%), prostrate kelps (2-19%), and crustose coralline algae (0-19%) dominated the epilithic community. Strong spatial distinctions among sites included a positive correlation between cover by crustose coralline algae and distance to river inputs. We found no significant relationships between environmental factors and functional groups. Differences between early-successional and established benthic communities indicated that slow growth rates result in prolonged community development, augmented by strong abiotic control over local community structure. Growth and post-recruitment mortality determine crustose coralline algae and invertebrate prevalence in the established community, while kelp seem to be largely recruitment-limited. On scales >1 m, community structure depends on bathymetry and exposure to freshwater intrusion. Colonization rates (means of 3.3-69.9 ind. 100 cm-1 year-1 per site) were much lower than studies in other Arctic kelp habitats, and likely reflect the nature of a truly High Arctic environment. Our results suggest that community development in the nearshore Beaufort Sea occurs over decades, and is affected by combinations of recruitment limitation, primary disturbance, and seasonal abiotic stressors. While seasonality exerts strong influence on Arctic systems, static habitat characteristics connect seasonal variability to benthic ecosystem structure by integrating abiotic conditions over timescales longer than most ecological studies.", "publicationTitle": "Frontiers in Marine Science", "publisher": "Frontiers", "place": "", "date": "2021", "volume": "8", "issue": "", "section": "", "partNumber": "", "partTitle": "", "pages": "", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Front. Mar. Sci.", "DOI": "10.3389/fmars.2021.592295", "citationKey": "", "url": "https://www.frontiersin.org/articles/10.3389/fmars.2021.592295/full", "accessDate": "2021-07-28T13:33:33Z", "PMID": "", "PMCID": "", "ISSN": "2296-7745", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "English", "libraryCatalog": "Frontiers", "callNumber": "", "rights": "", "extra": "https://doi.org/10.6073/pasta/e0e71c2d59bf7b08928061f546be6a9a", "tags": [ { "tag": "Arctic", "type": 1 }, { "tag": "Benthic Ecology", "type": 1 }, { "tag": "Coastal occanography", "type": 1 }, { "tag": "Kelp", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "LTER-Funded" }, { "tag": "Supported" }, { "tag": "community structure", "type": 1 }, { "tag": "recruitment", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5", "ZQZ83R7H" ], "relations": {}, "dateAdded": "2021-07-28T13:33:33Z", "dateModified": "2026-10-21T16:53:19Z" } }, { "key": "UL342LCY", "version": 1137, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/UL342LCY", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/UL342LCY", "type": "text/html" } }, "meta": { "createdByUser": { "id": 5056957, "username": "BLE-IM", "name": "Tim Whiteaker", "links": { "alternate": { "href": "https://www.zotero.org/ble-im", "type": "text/html" } } }, "lastModifiedByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Demir et al.", "parsedDate": "2024-11-28", "numChildren": 0 }, "data": { "key": "UL342LCY", "version": 1137, "itemType": "journalArticle", "title": "Coastal Supra‐Permafrost Aquifers of the Arctic and Their Significant Groundwater, Carbon, and Nitrogen Fluxes", "creators": [ { "creatorType": "author", "firstName": "Cansu", "lastName": "Demir" }, { "creatorType": "author", "firstName": "James W.", "lastName": "McClelland" }, { "creatorType": "author", "firstName": "Emily", "lastName": "Bristol" }, { "creatorType": "author", "firstName": "Matthew A.", "lastName": "Charette" }, { "creatorType": "author", "firstName": "M. Bayani", "lastName": "Cardenas" } ], "abstractNote": "Abstract\n \n Fresh submarine groundwater discharge (FSGD) can deliver significant fluxes of water and solutes from land to sea. In the Arctic, which accounts for ∼34% of coastlines globally, direct observations and knowledge of FSGD are scarce. Through integration of observations and process‐based models, we found that regardless of ice‐bonded permafrost depth at the shore, summer SGD flow dynamics along portions of the Beaufort Sea coast of Alaska are similar to those in lower latitudes. Calculated summer FSGD fluxes in the Arctic are generally higher relative to low latitudes. The FSGD organic carbon and nitrogen fluxes are likely larger than summer riverine input. The FSGD also has very high CO\n 2\n making it a potentially significant source of inorganic carbon. Thus, the biogeochemistry of Arctic coastal waters is potentially influenced by groundwater inputs during summer. These water and solute fluxes will likely increase as coastal permafrost across the Arctic thaws.\n \n , \n Plain Language Summary\n Groundwater flows from land to sea, transporting freshwater, organic matter, nutrients, and other solutes that impact coastal ecosystems. However, along coasts of the rapidly‐warming Arctic, there is limited knowledge regarding how much fresh groundwater enters the ocean. Using field observations and numerical models, we show that groundwater flowing from tundra in northern coastal Alaska carries large amounts of freshwater, organic matter, and carbon dioxide to the Arctic lagoons during summer. These inputs are likely significant to coastal biogeochemical cycling and marine food webs. Groundwater discharge and the associated transport of dissolved materials are expected to increase due to longer periods of above‐zero temperatures that thaw frozen soils below the tundra.\n , \n Key Points\n \n \n \n Summer fresh submarine groundwater discharge (FSGD) to the Alaskan Beaufort Sea is only 3%–7% of rivers but carries as much organic matter\n \n \n Summer FSGD delivers a median of 116 (interquartile range: 35–405) and 6 (2–21) kg/d per km dissolved organic carbon and nitrogen\n \n \n \n Fresh groundwater at the beach of Simpson Lagoon (SL) has a median PCO\n 2\n of ∼33,000 μatm implying substantial CO\n 2\n flux", "publicationTitle": "Geophysical Research Letters", "publisher": "", "place": "", "date": "2024-11-28", "volume": "51", "issue": "22", "section": "", "partNumber": "", "partTitle": "", "pages": "e2024GL109142", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Geophysical Research Letters", "DOI": "10.1029/2024GL109142", "citationKey": "", "url": "https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024GL109142", "accessDate": "2024-12-05T18:31:38Z", "PMID": "", "PMCID": "", "ISSN": "0094-8276, 1944-8007", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "DOI.org (Crossref)", "callNumber": "", "rights": "", "extra": "https://doi.org/10.6073/pasta/e0e71c2d59bf7b08928061f546be6a9a", "tags": [ { "tag": "LTER-BLE" }, { "tag": "Supported" } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2024-12-05T18:31:38Z", "dateModified": "2026-10-21T16:51:42Z" } }, { "key": "RDGLGPHG", "version": 1136, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/RDGLGPHG", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/RDGLGPHG", "type": "text/html" } }, "meta": { "createdByUser": { "id": 5056957, "username": "BLE-IM", "name": "Tim Whiteaker", "links": { "alternate": { "href": "https://www.zotero.org/ble-im", "type": "text/html" } } }, "lastModifiedByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Stanek et al.", "parsedDate": "2022-10-03", "numChildren": 0 }, "data": { "key": "RDGLGPHG", "version": 1136, "itemType": "journalArticle", "title": "Barrier islands influence the assimilation of terrestrial energy in nearshore fishes", "creators": [ { "creatorType": "author", "firstName": "Ashley E.", "lastName": "Stanek" }, { "creatorType": "author", "firstName": "Vanessa R.", "lastName": "von Biela" }, { "creatorType": "author", "firstName": "Sarah M.", "lastName": "Laske" }, { "creatorType": "author", "firstName": "Rebecca L.", "lastName": "Taylor" }, { "creatorType": "author", "firstName": "Kenneth H.", "lastName": "Dunton" } ], "abstractNote": "We examined the relative importance of landscape features on estuarine fish trophic structure and dependence on terrestrial organic matter (OMterr) in four barrier island lagoon systems along the Alaskan Beaufort Sea coast. Our study compared two relatively large lagoon systems characterized by high river discharge and relatively free ocean water exchanges (central region near Prudhoe Bay, Alaska) with two highly protected lagoons characterized by low river discharge and limited exchange with ocean waters (eastern region near Kaktovik, Alaska). We hypothesized that freshwater discharge would be a strong determinant of food web structure for both resident marine and diadromous fishes if more discharge increases availability of OMterr relative to lagoons with limited or no river inputs. To consider differences in trophic characteristics in fishes between study regions, we estimated community-wide measures of trophic structure (hereafter, community metrics) and the relative use of OMterr from mixing models using stable isotope composition (δ13C and δ15N; muscle tissue) among 12 species and identified the influences of region and body size. Fish captured in lagoons well protected by barrier islands had more distinct and diverse isotopic niches relative to those in more exposed lagoons based on community metrics. The use of OMterr by nearshore fishes in both regions was substantial and was >50% for diadromous species. Between regions, OMterr use differed in 6 of the 8 species considered but was not consistently higher in one region. The relative importance of OMterr varied with fish size in 7 of 10 species considered, with more OMterr used by smaller individuals. This work highlights the importance of OMterr to Arctic fishes and fisheries, some of which are of subsistence importance, even when feeding grounds are primarily marine. We propose that landscape features, particularly barrier islands, play an important role in structuring nearshore food webs. Barrier islands may provide a previously undocumented ecosystem service of increasing food web complexity, which may promote system resilience.", "publicationTitle": "Estuarine, Coastal and Shelf Science", "publisher": "", "place": "", "date": "2022-10-03", "volume": "", "issue": "", "section": "", "partNumber": "", "partTitle": "", "pages": "108094", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Estuarine, Coastal and Shelf Science", "DOI": "10.1016/j.ecss.2022.108094", "citationKey": "", "url": "https://www.sciencedirect.com/science/article/pii/S0272771422003523", "accessDate": "2022-10-03T21:17:19Z", "PMID": "", "PMCID": "", "ISSN": "0272-7714", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "ScienceDirect", "callNumber": "", "rights": "", "extra": "https://doi.org/10.5066/P9DAFMJD\nhttps://doi.org/10.6073/pasta/38d4e92e56b078cfad442c64e4f6b71e", "tags": [ { "tag": "Alaska", "type": 1 }, { "tag": "Beaufort sea", "type": 1 }, { "tag": "Carbon", "type": 1 }, { "tag": "Food webs", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "LTER-Enabled" }, { "tag": "Lagoons", "type": 1 }, { "tag": "Nitrogen", "type": 1 }, { "tag": "Stable isotopes", "type": 1 }, { "tag": "Supported" }, { "tag": "USA", "type": 1 } ], "collections": [ "IJ4K8DFH", "JK9MDZ2M", "KHTHLKB5" ], "relations": {}, "dateAdded": "2022-10-03T21:17:19Z", "dateModified": "2026-10-21T16:43:55Z" } }, { "key": "ZM8UNBU6", "version": 1135, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/ZM8UNBU6", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/ZM8UNBU6", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Spera et al.", "parsedDate": "2026-01-20", "numChildren": 0 }, "data": { "key": "ZM8UNBU6", "version": 1135, "itemType": "journalArticle", "title": "Wind-driven Circulation Impacts Water Quality and pCO2 Over an Estuarine Gradient in an Arctic Lagoon", "creators": [ { "creatorType": "author", "firstName": "Alina", "lastName": "Spera" }, { "creatorType": "author", "firstName": "Sasha", "lastName": "Peterson" }, { "creatorType": "author", "firstName": "Craig", "lastName": "Tweedie" }, { "creatorType": "author", "firstName": "Vanessa", "lastName": "Lougheed" } ], "abstractNote": "Arctic carbon (C) budgets typically exclude estuarine and coastal CO2 dynamics despite evidence that these systems can be a source of atmospheric CO2, unlike the shelf waters and the open ocean. High frequency measurements of Arctic coastal pCO2 are limited but needed to understand C cycling responses to interacting influences of terrestrial and oceanic inputs. We measured continuous pCO2 and estimated CO2 fluxes during three open water seasons at five sites across an Arctic estuary, including three shallow sites (≤ 1 m), and two deep sites (> 2 m). During the open water season, wind-driven currents controlled the distribution of terrestrial and marine materials, which influenced spatial and temporal patterns - both daily and interannual - in lagoon water quality. Lagoon waters generally had undersaturated pCO₂ relative to the atmosphere, particularly at the deeper sites. pCO₂ increased or reached saturation at all sites when wind-driven circulation enhanced terrestrial influence that led to warmer, fresher conditions with elevated light attenuation and higher apparent oxygen utilization. On average, two shallow sites were sources of CO2 to the atmosphere, potentially due to their proximity to eroding coastal bluffs, inputs from an intermediate-sized river, and wind driven resuspension events. Continuous measurements and high spatial coverage are important to detect and scale CO2 fluxes across the open water season in the Arctic nearshore zone, especially those draining understudied, smaller watersheds.", "publicationTitle": "Estuaries and Coasts", "publisher": "", "place": "", "date": "2026-01-20", "volume": "49", "issue": "2", "section": "", "partNumber": "", "partTitle": "", "pages": "49", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Estuaries and Coasts", "DOI": "10.1007/s12237-025-01662-6", "citationKey": "", "url": "https://doi.org/10.1007/s12237-025-01662-6", "accessDate": "2026-01-20T21:08:08Z", "PMID": "", "PMCID": "", "ISSN": "1559-2731", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "Springer Link", "callNumber": "", "rights": "", "extra": "https://doi.org/10.6073/pasta/bd140df496a851ced06f8f03445f73ab\nhttps://doi.org/10.6073/pasta/755d4a016fcc053c6dcd816be97d0e7e", "tags": [ { "tag": "Arctic lagoon", "type": 1 }, { "tag": "CO2 flux, light attenuation", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "Supported" }, { "tag": "Wind-driven circulation", "type": 1 }, { "tag": "pCO2 dynamics", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-01-20T21:08:08Z", "dateModified": "2026-10-21T16:41:25Z" } }, { "key": "QNJRKD4K", "version": 1134, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/QNJRKD4K", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/QNJRKD4K", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Connolly et al.", "parsedDate": "2026", "numChildren": 1 }, "data": { "key": "QNJRKD4K", "version": 1134, "itemType": "journalArticle", "title": "Landscape Controls River Continuum Dissolved Organic Carbon in Northeastern Alaska", "creators": [ { "creatorType": "author", "firstName": "C. T.", "lastName": "Connolly" }, { "creatorType": "author", "firstName": "J. C.", "lastName": "Koch" }, { "creatorType": "author", "firstName": "J. W.", "lastName": "McClelland" }, { "creatorType": "author", "firstName": "M. A.", "lastName": "Rawlins" }, { "creatorType": "author", "firstName": "M.", "lastName": "Repasch" } ], "abstractNote": "Rivers draining continuous permafrost landscapes on the North Slope of Alaska span from the mountains to the coast, integrating gradients in vegetation, soil organic matter, and hydrologic flow. We investigated how these landscape transitions influence dissolved organic carbon (DOC) concentrations, radiocarbon ages, and export along the river continuum over seasonal timeframes in northeastern Alaska. Water samples were collected from the Canning River and its tributaries from the spring freshet through late summer via multiple campaigns during 2011–2024. A simulation from the Permafrost Water Balance Model (PWBM) estimated terrain-specific contributions to freshwater and DOC export. River DOC concentrations peaked during the spring and declined in summer, with episodic increases linked to summer rainfall. Summer river DOC concentrations from the Brooks Range remained low (0.41–0.64 mg C L−1) but increased downstream (0.5–3.0 mg C L−1), becoming younger from the mountains (805 yBP) to the river delta (525 yBP) as flow from DOC-enriched streams draining the foothills (6–18 mg C L−1; Modern yBP) entered the Canning. The PWBM simulation revealed that while the mountains dominate the Canning's annual (90%) and spring-summer (88%–93%) freshwater export, the foothills disproportionately influence its annual (56%) and spring-summer (44%–58%) DOC export. DOC yields from the coastal plain were also high but had little influence due to its small contributing area. Our findings highlight the outsized role of the foothills in modulating river-integrated DOC export to coastal ecosystems. Considering the impact of these landscapes on carbon source and runoff will aid in anticipating future DOC fluxes from Arctic rivers.", "publicationTitle": "Water Resources Research", "publisher": "", "place": "", "date": "2026", "volume": "62", "issue": "9", "section": "", "partNumber": "", "partTitle": "", "pages": "e2025WR042358", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1029/2025WR042358", "citationKey": "", "url": "https://onlinelibrary.wiley.com/doi/abs/10.1029/2025WR042358", "accessDate": "2026-10-05T14:12:27Z", "PMID": "", "PMCID": "", "ISSN": "1944-7973", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "Wiley Online Library", "callNumber": "", "rights": "© 2026 The Author(s). Water Resources Research published by Wiley Periodicals LLC on behalf of American Geophysical Union. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.", "extra": "https://doi.org/10.6073/pasta/543de845044f3fc573b919b57d190a83", "tags": [ { "tag": "Arctic", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "Supported" }, { "tag": "dissolved organic matter", "type": 1 }, { "tag": "landscape contributions", "type": 1 }, { "tag": "rivers", "type": 1 }, { "tag": "streams", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-10-05T14:12:27Z", "dateModified": "2026-10-05T14:14:45Z" } }, { "key": "JIHNG2Y4", "version": 1130, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/JIHNG2Y4", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/JIHNG2Y4", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/2211939/items/QNJRKD4K", "type": "application/json" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "JIHNG2Y4", "version": 1130, "parentItem": "QNJRKD4K", "itemType": "note", "note": "e2025WR042358 2025WR042358
", "tags": [], "relations": {}, "dateAdded": "2026-10-05T14:12:27Z", "dateModified": "2026-10-05T14:12:27Z" } }, { "key": "H7TFK46Y", "version": 1128, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/H7TFK46Y", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/H7TFK46Y", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Demir et al.", "parsedDate": "2026", "numChildren": 1 }, "data": { "key": "H7TFK46Y", "version": 1128, "itemType": "journalArticle", "title": "Time-Varying Hydroclimatic and Oceanic Controls on Arctic Submarine Groundwater Discharge Inferred Using Explainable AI", "creators": [ { "creatorType": "author", "firstName": "Cansu", "lastName": "Demir" }, { "creatorType": "author", "firstName": "Jesus D.", "lastName": "Gomez-Velez" }, { "creatorType": "author", "firstName": "Julia", "lastName": "Guimond" }, { "creatorType": "author", "firstName": "James W.", "lastName": "McClelland" }, { "creatorType": "author", "firstName": "Matthew A.", "lastName": "Charette" }, { "creatorType": "author", "firstName": "M.", "lastName": "Bayani Cardenas" } ], "abstractNote": "Submarine groundwater discharge (SGD), an important component of coastal water and nutrient budgets, is challenging to monitor and predict in the Arctic given the remoteness and harsh conditions. Here, we used explainable artificial intelligence to quantify the time-varying importance of hydroclimatic and oceanic drivers of SGD at an Arctic beach from the early thaw period to late summer. Deep learning models were trained on in situ observations and reanalysis data, and feature contributions to model prediction were quantified using SHAP (Shapley Additive Explanations). We learned the following: potential evaporation is the dominant control on groundwater storage and SGD over seasonal scales; winds regulate short-term groundwater levels and intermediate-term discharge; soil temperature modulates groundwater storage via thaw-driven processes; and precipitation is important for short-term groundwater flushing and seasonal-scale storage. These insights on the scale-dependent SGD controls establish a framework for hindcasting and forecasting groundwater dynamics in remote Arctic environments.", "publicationTitle": "Geophysical Research Letters", "publisher": "", "place": "", "date": "2026", "volume": "53", "issue": "15", "section": "", "partNumber": "", "partTitle": "", "pages": "e2026GL123641", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1029/2026GL123641", "citationKey": "", "url": "https://onlinelibrary.wiley.com/doi/abs/10.1029/2026GL123641", "accessDate": "2026-07-30T15:21:42Z", "PMID": "", "PMCID": "", "ISSN": "1944-8007", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "Wiley Online Library", "callNumber": "", "rights": "© 2026 The Author(s). Geophysical Research Letters published by Wiley Periodicals LLC on behalf of American Geophysical Union.", "extra": "_eprint: https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2026GL123641", "tags": [ { "tag": "Arctic", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "Supported" }, { "tag": "coastal", "type": 1 }, { "tag": "deep learning", "type": 1 }, { "tag": "drivers", "type": 1 }, { "tag": "explainable AI", "type": 1 }, { "tag": "groundwater", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-07-30T15:21:42Z", "dateModified": "2026-07-30T15:22:16Z" } }, { "key": "GENZ4MVV", "version": 1125, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/GENZ4MVV", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/GENZ4MVV", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/2211939/items/H7TFK46Y", "type": "application/json" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "GENZ4MVV", "version": 1125, "parentItem": "H7TFK46Y", "itemType": "note", "note": "e2026GL123641 2026GL123641
", "tags": [], "relations": {}, "dateAdded": "2026-07-30T15:21:42Z", "dateModified": "2026-07-30T15:21:42Z" } }, { "key": "69PHRJ5I", "version": 1123, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/69PHRJ5I", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/69PHRJ5I", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Frantz et al.", "parsedDate": "2026", "numChildren": 0 }, "data": { "key": "69PHRJ5I", "version": 1123, "itemType": "journalArticle", "title": "Microbial Ecology of Rotten Sea Ice: Implications for Arctic Carbon Cycling with Global Warming", "creators": [ { "creatorType": "author", "firstName": "Carie M.", "lastName": "Frantz" }, { "creatorType": "author", "firstName": "Byron C.", "lastName": "Crump" }, { "creatorType": "author", "firstName": "Shelly", "lastName": "Carpenter" }, { "creatorType": "author", "firstName": "Erin", "lastName": "Firth" }, { "creatorType": "author", "firstName": "Mónica V.", "lastName": "Orellana" }, { "creatorType": "author", "firstName": "Bonnie", "lastName": "Light" }, { "creatorType": "author", "firstName": "Karen", "lastName": "Junge" } ], "abstractNote": "“Rotten” sea ice, ice in an advanced stage of melt, represents an important but understudied habitat in the rapidly changing Arctic. As Arctic warming accelerates, this late-season ice type will become more prevalent, yet little is known about its microbial inhabitants or their roles in Arctic marine biogeochemical cycles. We examined microbial communities (prokaryote and algal abundance, 16S and 18S rRNA gene and transcript sequencing) and biogeochemical properties of rotten sea ice and earlier-season ice near Utqiaġvik, Alaska, USA. Rotten ice was comparatively warm, isothermal, and largely drained of brine, with extensive, interconnected pore networks linked to melt ponds above and seawater below. Unlike earlier-season ice, fluids saturating rotten ice were vertically homogeneous in pH, dissolved inorganic carbon, prokaryote and phytoplankton abundance, and microbial community composition. However, particulate carbon and nitrogen exhibited strong vertical gradients, with the highest concentrations near the surface. Microbial communities in rotten ice were significantly different from those in earlier-season ice and varied between individual floes. These findings indicate that rotten ice constitutes a distinct microbial habitat and may serve as an important source of nutrient-rich particulate matter in the future Arctic Ocean during the summer melt season.", "publicationTitle": "Microorganisms", "publisher": "Multidisciplinary Digital Publishing Institute", "place": "", "date": "2026", "volume": "14", "issue": "2", "section": "", "partNumber": "", "partTitle": "", "pages": "482", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.3390/microorganisms14020482", "citationKey": "", "url": "https://www.mdpi.com/2076-2607/14/2/482", "accessDate": "2026-07-22T14:48:31Z", "PMID": "", "PMCID": "", "ISSN": "2076-2607", "archive": "", "archiveLocation": "", "shortTitle": "Microbial Ecology of Rotten Sea Ice", "language": "en", "libraryCatalog": "www.mdpi.com", "callNumber": "", "rights": "http://creativecommons.org/licenses/by/3.0/", "extra": "", "tags": [ { "tag": "Arctic shelf ecosystems", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "Supported" }, { "tag": "biogeochemical gradients", "type": 1 }, { "tag": "extracellular polymeric substances", "type": 1 }, { "tag": "particulate organic matter", "type": 1 }, { "tag": "polar microbial diversity", "type": 1 }, { "tag": "sea ice melt dynamics", "type": 1 }, { "tag": "sympagic microbiome", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-07-22T14:48:31Z", "dateModified": "2026-07-22T14:49:26Z" } }, { "key": "GMTHLINC", "version": 1118, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/GMTHLINC", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/GMTHLINC", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Wilkinson et al.", "parsedDate": "2026-03-01", "numChildren": 0 }, "data": { "key": "GMTHLINC", "version": 1118, "itemType": "journalArticle", "title": "Patterns of trophic niche overlap of diadromous and marine Arctic fishes in Beaufort Sea coastal lagoons", "creators": [ { "creatorType": "author", "firstName": "Sydney", "lastName": "Wilkinson" }, { "creatorType": "author", "firstName": "Lara", "lastName": "Horstmann" }, { "creatorType": "author", "firstName": "Benjamin D.", "lastName": "Barst" }, { "creatorType": "author", "firstName": "Todd", "lastName": "Sformo" }, { "creatorType": "author", "firstName": "Trent", "lastName": "Sutton" }, { "creatorType": "author", "firstName": "Kenneth", "lastName": "Dunton" }, { "creatorType": "author", "firstName": "Katrin", "lastName": "Iken" } ], "abstractNote": "Ongoing climatic changes in the coastal Arctic can influence the food webs that support a variety of fish species and subsistence fisheries in coastal lagoons. Along the Beaufort Sea coast, lagoons provide productive summer feeding habitats for both diadromous fishes migrating from freshwater and marine fishes migrating from the shelf. We compared trophic niche size and niche overlap between diadromous species, Arctic Cisco (Coregonus autumnalis), Least Cisco (Coregonus sardinella), and Dolly Varden (Salvelinus malma), and marine species, Polar Cod (Boreogadus saida), Fourhorn Sculpin (Myoxocephalus quadricornis), and Saffron Cod (Eleginus gracilis), across lagoon systems differing in freshwater input and oceanic exchange. Using complementary biomarkers (stomach contents, bulk δ13C and δ15N, compound-specific amino acid δ13C, and fatty acid profiles), we found that diadromous fishes consistently exhibited broader trophic niches than marine fishes, reflecting their ability to exploit both freshwater and offshore pelagic resources. Trophic overlap occurred across the two life histories in both lagoon types, but was greater in high-exchange lagoons, primarily due to shared reliance on amphipods, mysids, and marine carbon sources. Considering the different biomarker turnover times, this overlap likely extends from late winter ice cover into open water periods. These results suggest that competition for prey is probable among species with contrasting life histories, particularly during periods of low prey abundance. By resolving seasonal and spatial patterns of trophic overlap, our findings provide important baseline knowledge for modeling future scenarios of lagoon connectivity and for informing subsistence fisheries management under ongoing changes in the Arctic.", "publicationTitle": "Estuarine, Coastal and Shelf Science", "publisher": "", "place": "", "date": "2026-03-01", "volume": "330", "issue": "", "section": "", "partNumber": "", "partTitle": "", "pages": "109657", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Estuarine, Coastal and Shelf Science", "DOI": "10.1016/j.ecss.2025.109657", "citationKey": "", "url": "https://www.sciencedirect.com/science/article/pii/S0272771425005359", "accessDate": "2026-07-22T13:36:46Z", "PMID": "", "PMCID": "", "ISSN": "0272-7714", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "", "libraryCatalog": "ScienceDirect", "callNumber": "", "rights": "", "extra": "https://doi.org/10.6073/pasta/0d66fcc8c034d53b435672ca8e1a09bd", "tags": [ { "tag": "LTER-BLE" }, { "tag": "Supported" } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-07-22T13:36:46Z", "dateModified": "2026-07-22T13:37:38Z" } }, { "key": "4KD9H4E4", "version": 1113, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/4KD9H4E4", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/4KD9H4E4", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Demir et al.", "parsedDate": "2026", "numChildren": 1 }, "data": { "key": "4KD9H4E4", "version": 1113, "itemType": "journalArticle", "title": "Hydrological and Thermal Dynamics of a Supra-Permafrost Subterranean Estuary", "creators": [ { "creatorType": "author", "firstName": "Cansu", "lastName": "Demir" }, { "creatorType": "author", "firstName": "Julia A.", "lastName": "Guimond" }, { "creatorType": "author", "firstName": "Emily M.", "lastName": "Bristol" }, { "creatorType": "author", "firstName": "Emma", "lastName": "Bullock" }, { "creatorType": "author", "firstName": "James W.", "lastName": "McClelland" }, { "creatorType": "author", "firstName": "Matthew A.", "lastName": "Charette" }, { "creatorType": "author", "firstName": "M. Bayani", "lastName": "Cardenas" } ], "abstractNote": "Subterranean estuaries (STEs), where groundwater interacts with seawater, influence surface and subsurface coastal ecology and biogeochemistry. In Arctic-STEs overlying permafrost, groundwater flow and heat transport determine the fate of organic matter. Yet, direct observations of groundwater flow and heat and solute transport processes in Arctic STEs remain limited. This study characterized groundwater flow paths and fluxes and heat transport within an Arctic-STE along Alaska's Beaufort Sea coast during thawing, summer, and freeze-up. Intertidal seabed temperature-depth profiles collected along a 10-m transect captured the active groundwater flow period, from thaw and flow onset in mid-June to freeze-up in late-September. During this period, aquifer geometry evolved non-uniformly due to spatially varying thaw rates across the STE (mean (m) thaw depths–beach: 0.25 to 0.55–0.6 m on 20 June, 25 July, 1 October; seabed: 0.6–0.9 m from 25 July to 1 October). Groundwater and surface water levels, salinity, and subsurface temperature profiles measured over tidal time scales were interpreted alongside groundwater flow-heat transport numerical simulations. Fresh groundwater discharge was sporadic during thawing (m: 0.32 m3/day/m), abundant in summer (m: 0.45 m3/day/m), and was largely absent during freeze-up. During freeze-up, groundwater flow was driven exclusively by seawater recirculation via tidal pumping (from thawing to summer to freeze-up: 0.00025–0.15–0.5 m3/day/m) and convection. Heat advection dominated near aquatic interfaces (shaping intertidal ice), and conduction controlled vertical temperature gradients in low-flow and unsaturated sediments. These findings will help predict how prolonged summers will alter Arctic-STE cryo-hydrology and biogeochemistry.", "publicationTitle": "Water Resources Research", "publisher": "", "place": "", "date": "2026", "volume": "62", "issue": "5", "section": "", "partNumber": "", "partTitle": "", "pages": "e2025WR041790", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1029/2025WR041790", "citationKey": "", "url": "https://onlinelibrary.wiley.com/doi/abs/10.1029/2025WR041790", "accessDate": "2026-07-10T17:58:25Z", "PMID": "", "PMCID": "", "ISSN": "1944-7973", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "Wiley Online Library", "callNumber": "", "rights": "© 2026. The Author(s).", "extra": "_eprint: https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2025WR041790", "tags": [ { "tag": "Arctic subterranean estuary", "type": 1 }, { "tag": "Beaufort Sea lagoons", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "Supported" }, { "tag": "coastal groundwater", "type": 1 }, { "tag": "cryohydrogeology", "type": 1 }, { "tag": "groundwater surface water interactions", "type": 1 }, { "tag": "submarine groundwater discharge", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-07-10T17:58:25Z", "dateModified": "2026-07-10T17:58:39Z" } }, { "key": "964GN3GC", "version": 1111, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/964GN3GC", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/964GN3GC", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/2211939/items/4KD9H4E4", "type": "application/json" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "964GN3GC", "version": 1111, "parentItem": "4KD9H4E4", "itemType": "note", "note": "e2025WR041790 2025WR041790
", "tags": [], "relations": {}, "dateAdded": "2026-07-10T17:58:25Z", "dateModified": "2026-07-10T17:58:25Z" } }, { "key": "IBL6Q7ZA", "version": 1109, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/IBL6Q7ZA", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/IBL6Q7ZA", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Connolly et al.", "parsedDate": "2026", "numChildren": 0 }, "data": { "key": "IBL6Q7ZA", "version": 1109, "itemType": "journalArticle", "title": "Elucidating the Reactivity and Fate of Dissolved Organic Matter in Groundwater Entering the Alaska Beaufort Sea Coast Using 14C Ramped Oxidation", "creators": [ { "creatorType": "author", "firstName": "C. T.", "lastName": "Connolly" }, { "creatorType": "author", "firstName": "R. G. M.", "lastName": "Spencer" }, { "creatorType": "author", "firstName": "J. W.", "lastName": "McClelland" } ], "abstractNote": "Ramped oxidation and isotopic analysis provide a framework for assessing organic matter transformation and fate across Arctic waters\n\nSupra-permafrost groundwater exhibits an aged but reactive mid...", "publicationTitle": "", "publisher": "", "place": "", "date": "2026", "volume": "", "issue": "", "section": "", "partNumber": "", "partTitle": "", "pages": "", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1029/2025GL121357", "citationKey": "", "url": "https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025GL121357", "accessDate": "2026-07-10T17:54:11Z", "PMID": "", "PMCID": "", "ISSN": "", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "agupubs.onlinelibrary.wiley.com", "callNumber": "", "rights": "", "extra": "https://doi.org/10.6073/pasta/a4105a1bd1f8fd167b3f7af7d06ad9f4", "tags": [ { "tag": "LTER-BLE" }, { "tag": "Supported" } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-07-10T17:54:11Z", "dateModified": "2026-07-10T17:56:10Z" } }, { "key": "KPPR866K", "version": 1105, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/KPPR866K", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/KPPR866K", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Mahoney and Einhorn", "parsedDate": "2026", "numChildren": 1 }, "data": { "key": "KPPR866K", "version": 1105, "itemType": "journalArticle", "title": "The Evolving Decline of Landfast Sea Ice in Northern Alaska and Adjacent Waters: Results from an Updated Climatology", "creators": [ { "creatorType": "author", "firstName": "Andrew R.", "lastName": "Mahoney" }, { "creatorType": "author", "firstName": "Andrew H.", "lastName": "Einhorn" } ], "abstractNote": "We present a new 27-year record of landfast sea ice extent in northern Alaska and adjacent waters, which uses ice chart data to extend a previous analysis based on synthetic aperture radar (SAR) imagery. This new climatology provides updated information on the decline of landfast ice in a region of the Arctic that has seen extensive losses of sea ice in recent summers. By comparing our results with early satellite data analysis from the 1970s, we find that trends in the timing of landfast ice have been ongoing for at least 50 years. Over the period 1996–2023, the landfast season shortened by 19 days/decade in the Chukchi Sea and 13 days/decade in the Beaufort Sea, primarily due to later formation of landfast ice. Also, the time between onset of freezing air temperatures and landfast ice formation is increasing, which is consistent with a coastal ocean that takes longer to freeze. While it was previously reported that the typical annual maximum width of landfast ice in the Chukchi Sea declined by 13 km between periods 1970–1976 and 1996–2008, we find this retreat has slowed with a decline of 3.3 km over the course of our data set as few areas of extensive landfast remain to be lost. Conversely, landfast sea ice extent in the Beaufort Sea had previously been found to have remained constant since the 1970s, but we find an average reduction of 2.5 km. We attribute this emergent phenomenon to a reduction in the number grounded ridges forming offshore.", "publicationTitle": "Journal of Geophysical Research: Oceans", "publisher": "", "place": "", "date": "2026", "volume": "131", "issue": "1", "section": "", "partNumber": "", "partTitle": "", "pages": "e2025JC022464", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1029/2025JC022464", "citationKey": "", "url": "https://onlinelibrary.wiley.com/doi/abs/10.1029/2025JC022464", "accessDate": "2026-04-07T17:54:24Z", "PMID": "", "PMCID": "", "ISSN": "2169-9291", "archive": "", "archiveLocation": "", "shortTitle": "The Evolving Decline of Landfast Sea Ice in Northern Alaska and Adjacent Waters", "language": "en", "libraryCatalog": "Wiley Online Library", "callNumber": "", "rights": "© 2026. The Author(s).", "extra": "_eprint: https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2025JC022464", "tags": [ { "tag": "Alaska", "type": 1 }, { "tag": "Arctic", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "Supported" }, { "tag": "fast ice", "type": 1 }, { "tag": "landfast", "type": 1 }, { "tag": "sea ice", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-04-07T17:54:24Z", "dateModified": "2026-04-07T18:06:31Z" } }, { "key": "9HLZGFB3", "version": 1102, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/9HLZGFB3", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/9HLZGFB3", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/2211939/items/KPPR866K", "type": "application/json" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "9HLZGFB3", "version": 1102, "parentItem": "KPPR866K", "itemType": "note", "note": "e2025JC022464 2025JC022464
", "tags": [], "relations": {}, "dateAdded": "2026-04-07T17:54:24Z", "dateModified": "2026-04-07T17:54:24Z" } }, { "key": "YZRNL8GM", "version": 1100, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/YZRNL8GM", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/YZRNL8GM", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Rawlins et al.", "parsedDate": "2026", "numChildren": 1 }, "data": { "key": "YZRNL8GM", "version": 1100, "itemType": "journalArticle", "title": "Hydrological Cycle Intensification and Permafrost Thaw Drive Increased Freshwater and Organic Carbon Inputs to Northern Alaska Estuaries", "creators": [ { "creatorType": "author", "firstName": "Michael A.", "lastName": "Rawlins" }, { "creatorType": "author", "firstName": "Craig T.", "lastName": "Connolly" }, { "creatorType": "author", "firstName": "James W.", "lastName": "McClelland" } ], "abstractNote": "Understanding how hydrological inflows and climate change influence individual estuaries across northern Alaska is limited by a paucity of measured data, necessitating the application of suitably scaled numerical process models. This study uses an updated model to quantify freshwater discharge and dissolved organic carbon (DOC) export from the North Slope of Alaska (NSA) to coastal waters of the Beaufort Sea and examines climate-linked temporal changes. The model was applied at 1 \\textkm\\ resolution across the 166,483 {\\textkm^2\\ NSA domain over 1980–2023. Watershed inputs to coastal waters were estimated by routing along river networks to 1,039 outlets at the land-sea boundary. Key simulation parameters were evaluated to demonstrate model efficacy, then spatial and temporal patterns were quantified. Exports to specific lagoons, bays, and sounds demonstrate how landscape composition, terrestrial drainage basin size, and estuary area modulate watershed influence on coastal ecosystems across the region. Freshwater discharge and DOC export increased over the greater than four decades, associated with changes in precipitation and permafrost thaw. Surface and supra-permafrost subsurface fluxes also increased, with pronounced rises in proportional contributions via subsurface flow during summer and autumn. These changes have the potential to substantially impact salinity and trophic conditions along Alaska's Beaufort Sea coast. Our study highlights the value of model-data syntheses that resolve regional-to-local scale fluxes where observational measurements are sparse, and provides novel quantitative export metrics that will be useful to researchers, resource managers, and other stakeholders with interests in the climate, hydrology, and biogeochemistry of coastal northern Alaska.", "publicationTitle": "Global Biogeochemical Cycles", "publisher": "", "place": "", "date": "2026", "volume": "40", "issue": "4", "section": "", "partNumber": "", "partTitle": "", "pages": "e2025GB008822", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1029/2025GB008822", "citationKey": "", "url": "https://onlinelibrary.wiley.com/doi/abs/10.1029/2025GB008822", "accessDate": "2026-04-01T15:40:07Z", "PMID": "", "PMCID": "", "ISSN": "1944-9224", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "Wiley Online Library", "callNumber": "", "rights": "© 2026. The Author(s).", "extra": "_eprint: https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2025GB008822\n\nhttps://doi.org/10.6073/pasta/357705281a44f92f643e4d7f5b29ed82", "tags": [ { "tag": "Arctic", "type": 1 }, { "tag": "DOC", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "Supported" }, { "tag": "climate", "type": 1 }, { "tag": "hydrology", "type": 1 }, { "tag": "permafrost", "type": 1 }, { "tag": "rivers", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-04-01T15:40:07Z", "dateModified": "2026-04-01T15:40:53Z" } }, { "key": "JFKW9NAJ", "version": 1098, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/JFKW9NAJ", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/JFKW9NAJ", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/2211939/items/YZRNL8GM", "type": "application/json" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "JFKW9NAJ", "version": 1098, "parentItem": "YZRNL8GM", "itemType": "note", "note": "e2025GB008822 2025GB008822
", "tags": [], "relations": {}, "dateAdded": "2026-04-01T15:40:07Z", "dateModified": "2026-04-01T15:40:07Z" } }, { "key": "IYHTU3PZ", "version": 1096, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/IYHTU3PZ", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/IYHTU3PZ", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Marvy et al.", "parsedDate": "2026", "numChildren": 1 }, "data": { "key": "IYHTU3PZ", "version": 1096, "itemType": "journalArticle", "title": "Contrasting CO2 Fluxes Among Arctic Pond Types Are Driven by Differences in Carbon Lability, Terrestrial Inputs, and Benthic Respiration", "creators": [ { "creatorType": "author", "firstName": "Asher J.", "lastName": "Marvy" }, { "creatorType": "author", "firstName": "Christian G.", "lastName": "Andresen" }, { "creatorType": "author", "firstName": "Alina C.", "lastName": "Spera" }, { "creatorType": "author", "firstName": "Vanessa L.", "lastName": "Lougheed" } ], "abstractNote": "Small freshwater tundra ponds are hotspots for greenhouse gas release into the atmosphere. As the Arctic warms, thermokarst processes drive changes in tundra pond geomorphology, with implications for their contribution to carbon cycling in these regions. To understand how these morphological changes affect pond biogeochemistry, we compared low-centered polygonal (LCP) ponds and thermokarst trough (TKT) ponds that are formed through ice-wedge permafrost thaw. We found substantially higher levels of carbon, nutrients, and algal biomass in TKT ponds as compared to LCP ponds located in the Arctic Coastal Plain near Utqiaġvik, AK. These differences were likely driven by TKT ponds receiving increased terrestrial inputs due to discrete thermokarst events and slumping, lateral inflow of carbon and nutrients from surrounding soils, higher lability of TKT carbon, and greater rates of benthic respiration. Together, these factors create ponds that are more productive and greater sources of CO2 to the atmosphere than LCPs. During the peak growing season (July-August), CO2 uptake from macrophyte-dominated habitat in LCP ponds compensates for CO2 release from open water, making LCP ponds net CO2 sinks (−4 ± 3 gCO2/m2/d), whereas TKT ponds are CO2 sources (3 ± 6 gCO2/m2/d), despite TKT macrophyte-dominated habitat also being a site of CO2 uptake. The net atmospheric greenhouse gas contribution of these ponds will likely be altered with high latitude warming, as air temperature influenced factors including vegetation cover, precipitation, water temperature, and thermokarsting alter rates of CO2 flux from tundra ponds.", "publicationTitle": "Journal of Geophysical Research: Biogeosciences", "publisher": "", "place": "", "date": "2026", "volume": "131", "issue": "3", "section": "", "partNumber": "", "partTitle": "", "pages": "e2025JG009318", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1029/2025JG009318", "citationKey": "", "url": "https://onlinelibrary.wiley.com/doi/abs/10.1029/2025JG009318", "accessDate": "2026-03-16T13:17:08Z", "PMID": "", "PMCID": "", "ISSN": "2169-8961", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "Wiley Online Library", "callNumber": "", "rights": "© 2026. American Geophysical Union. All Rights Reserved.", "extra": "_eprint: https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2025JG009318\n\nhttps://doi.org/10.6073/pasta/4ff0d5ca036fcf28e3710d86468420e7", "tags": [ { "tag": "Arctic", "type": 1 }, { "tag": "LTER-BLE" }, { "tag": "Supported" }, { "tag": "biogeochemistry", "type": 1 }, { "tag": "carbon flux", "type": 1 }, { "tag": "thermokarst", "type": 1 }, { "tag": "tundra ponds", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-03-16T13:17:08Z", "dateModified": "2026-03-16T13:34:48Z" } }, { "key": "T4AXFXP3", "version": 1093, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/T4AXFXP3", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/T4AXFXP3", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/2211939/items/IYHTU3PZ", "type": "application/json" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "T4AXFXP3", "version": 1093, "parentItem": "IYHTU3PZ", "itemType": "note", "note": "e2025JG009318 2025JG009318
", "tags": [], "relations": {}, "dateAdded": "2026-03-16T13:17:08Z", "dateModified": "2026-03-16T13:17:08Z" } }, { "key": "FCKQ23HD", "version": 1006, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/FCKQ23HD", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/FCKQ23HD", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Stanek et al.", "parsedDate": "2024", "numChildren": 0 }, "data": { "key": "FCKQ23HD", "version": 1006, "itemType": "journalArticle", "title": "Arctic fishes reveal patterns in radiocarbon age across habitats and with recent climate change", "creators": [ { "creatorType": "author", "firstName": "Ashley E.", "lastName": "Stanek" }, { "creatorType": "author", "firstName": "Jonathan A.", "lastName": "O'Donnell" }, { "creatorType": "author", "firstName": "Michael P.", "lastName": "Carey" }, { "creatorType": "author", "firstName": "Sarah M.", "lastName": "Laske" }, { "creatorType": "author", "firstName": "Xiaomei", "lastName": "Xu" }, { "creatorType": "author", "firstName": "Kenneth H.", "lastName": "Dunton" }, { "creatorType": "author", "firstName": "Vanessa R.", "lastName": "von Biela" } ], "abstractNote": "Climate change alters the sources and age of carbon in Arctic food webs by fostering the release of older carbon from degrading permafrost. Radiocarbon (14C) traces carbon sources and age, but data before rapid warming are rare and limit assessments over time. We capitalized on 14C data collected 40 years ago that used fish as natural samplers by resampling the same species today. Among resampled fish, those using freshwater food webs had the oldest 14C ages (> 1000 yr BP), while those using marine food webs had the youngest 14C ages (near modern). One migratory species encompassed the entire range of 14C ages because juveniles fed in freshwater streams and adults fed in offshore marine habitats. Over 40 yr, average 14C ages of freshwater and marine feeding fish shifted closer to atmospheric values, suggesting a potential influence from “greening of the Arctic.”", "publicationTitle": "Limnology and Oceanography Letters", "publisher": "", "place": "", "date": "2024", "volume": "9", "issue": "6", "section": "", "partNumber": "", "partTitle": "", "pages": "796-805", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1002/lol2.10442", "citationKey": "", "url": "https://doi.org/10.1002/lol2.10442", "accessDate": "2026-01-26T21:13:14Z", "PMID": "", "PMCID": "", "ISSN": "2378-2242", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "en", "libraryCatalog": "Wiley Online Library", "callNumber": "", "rights": "", "extra": "_eprint: https://aslopubs.onlinelibrary.wiley.com/doi/pdf/10.1002/lol2.10442", "tags": [ { "tag": "LTER-BLE" }, { "tag": "Supported" } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-01-26T21:13:14Z", "dateModified": "2026-01-26T21:48:50Z" } }, { "key": "GHZSEHSF", "version": 1091, "library": { "type": "group", "id": 2211939, "name": "LTER-BLE", "links": { "alternate": { "href": "https://www.zotero.org/groups/lter-ble", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/2211939/items/GHZSEHSF", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/lter-ble/items/GHZSEHSF", "type": "text/html" } }, "meta": { "createdByUser": { "id": 13908241, "username": "Induja.UT", "name": "", "links": { "alternate": { "href": "https://www.zotero.org/induja.ut", "type": "text/html" } } }, "creatorSummary": "Bagavathyraj et al.", "parsedDate": "2026-01-21", "numChildren": 0 }, "data": { "key": "GHZSEHSF", "version": 1091, "itemType": "journalArticle", "title": "Segmentation of arctic coastal shoreline and bluff edges using optical satellite imagery and deep learning", "creators": [ { "creatorType": "author", "firstName": "Harshavardhini", "lastName": "Bagavathyraj" }, { "creatorType": "author", "firstName": "Sergio", "lastName": "Vargas Zesati" }, { "creatorType": "author", "firstName": "Olac", "lastName": "Fuentes" }, { "creatorType": "author", "firstName": "Sasha", "lastName": "Peterson" }, { "creatorType": "author", "firstName": "Craig E.", "lastName": "Tweedie" } ], "abstractNote": "The Arctic coastline spans multiple countries, supports Indigenous livelihoods, and plays a vital role in the Arctic system. Rapid climate change is accelerating permafrost thaw, sea-level rise, and coastal erosion, underscoring the need for decision making to be informed by accurate delineation of tundra shoreline (instantaneous water line) and bluff edge (vegetation–slope boundary) position and change trends. To address this need, we compared two image segmentation approaches for mapping Arctic land and water interfaces from high-resolution satellite imagery. (1) U-Net, a supervised convolutional neural network trained on expert-annotated scenes, and (2) Differentiable Feature Clustering (DifFeat), an unsupervised model applied in a minimally supervised manner via expert-guided cluster selection. The shoreline and bluff edge boundaries were derived from the segmented land and water masks using an automated interface extraction approach. DifFeat achieved higher segmentation accuracy, with IoU values of 0.95 (water) and 0.92 (land), compared to U-Net’s 0.58 and 0.50, respectively. U-Net produced reliable results and benefited from infrared and vegetation spectral indices, but required extensive annotation and showed limited generalization to UAV imagery. DifFeat achieved superior results without manual annotation, reducing the dependence on labeled data and completing training 99.87% faster than U-Net. These findings highlight the complementary strengths of supervised and semi-supervised models for Arctic coastal mapping, with DifFeat offering a scalable, label-efficient solution for long-term coastal-change monitoring. Future work will integrate elevation data to further improve bluff edge feature detection.", "publicationTitle": "Frontiers in Environmental Science", "publisher": "Frontiers", "place": "", "date": "2026-01-21", "volume": "13", "issue": "", "section": "", "partNumber": "", "partTitle": "", "pages": "", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Front. Environ. Sci.", "DOI": "10.3389/fenvs.2025.1657984", "citationKey": "", "url": "https://doi.org/10.3389/fenvs.2025.1657984", "accessDate": "2026-01-22T16:03:03Z", "PMID": "", "PMCID": "", "ISSN": "2296-665X", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "English", "libraryCatalog": "Frontiers", "callNumber": "", "rights": "", "extra": "", "tags": [ { "tag": "LTER-BLE" }, { "tag": "Supported" }, { "tag": "U-Net", "type": 1 }, { "tag": "bluff edge", "type": 1 }, { "tag": "deep learning", "type": 1 }, { "tag": "differentiable feature clustering", "type": 1 }, { "tag": "satellite imagery", "type": 1 }, { "tag": "segmentation", "type": 1 }, { "tag": "shoreline", "type": 1 }, { "tag": "unsupervised learning", "type": 1 } ], "collections": [ "IJ4K8DFH", "KHTHLKB5" ], "relations": {}, "dateAdded": "2026-01-22T16:03:03Z", "dateModified": "2026-01-22T16:27:57Z" } } ]