Previously undocumented subglacial lake beneath Flade Isblink stores most of catchment runoff and delays its release

Previously undocumented subglacial lake beneath Flade Isblink stores most of catchment runoff and delays its release | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Previously undocumented subglacial lake beneath Flade Isblink stores most of catchment runoff and delays its release Mikkel Aaby Kruse, Nanna Bjørnholt Karlsson, Penelope How, Anders Kusk, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8225226/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 11 You are reading this latest preprint version Abstract We report the discovery of a previously undocumented subglacial lake beneath the Flade Isblink Ice Cap in North East Greenland. Using satellite Earth Observation data from 2019 to 2025 and outputs from a regional climate model, we quantify the lake’s role in regional hydrology. The subglacial lake’s volume is characterised by an annual cycle of filling during the melt season and drainage in September-October, with the lake storing up to 74% of the yearly runoff from its catchment area. In most years, lake drainage causes a 2–3-month lag between peak surface-meltwater production and downstream discharge into the nearby proglacial lake, Romer Sø. Lake drainage occurred in all years in our observation period except 2022, which had the lowest surface melt rates, suggesting that a minimum water input threshold is required to initiate lake drainage. Additionally, we find that the lake is not hydrologically connected to the nearby, well-known subglacial lake on the high plateau of FladeIsblink. Our findings highlight how subglacial conditions may substantially modify the outflow of subglacial water to the ice margin with potential impacts on downstream hydrology and ecosystems. It further demonstrates the potential of integrating remote sensing with hydrological modelling to understand ice-sheet hydrology. Earth and environmental sciences/Climate sciences Earth and environmental sciences/Environmental sciences Earth and environmental sciences/Hydrology Full Text Additional Declarations No competing interests reported. Supplementary Files SupportingInformation.pdf Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 14 Jan, 2026 Reviews received at journal 22 Dec, 2025 Reviewers agreed at journal 17 Dec, 2025 Reviews received at journal 17 Dec, 2025 Reviewers agreed at journal 16 Dec, 2025 Reviewers agreed at journal 10 Dec, 2025 Reviewers invited by journal 10 Dec, 2025 Editor invited by journal 09 Dec, 2025 Editor assigned by journal 05 Dec, 2025 Submission checks completed at journal 05 Dec, 2025 First submitted to journal 27 Nov, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8225226","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":559574934,"identity":"7912233a-5f47-4fd7-87b9-1308da25b27a","order_by":0,"name":"Mikkel Aaby Kruse","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAz0lEQVRIiWNgGAWjYHACZgaGCiiTB0ScIUoLTBVPArFaGNtI0aLbfvixceW8ujz+9sMHGN7+OMzAd+YAfi1mZ9KME89uO1wscSYtgXFOwmEGybMNBLQcSDA+2LjtQGLDDR4DZh6gFoPzBBxmdv7554ONc+oS59/g/0Cklhs5xomNDcyJG27wMEC0EHTYjTfFhg3HDhcbnkkzODgnLZ1HkqD3z6dvlmyoqcuTO3744YM3NtZyfGcSCLgMCsDKQMbzEKcepmUUjIJRMApGAVYAADN5SkWzblmEAAAAAElFTkSuQmCC","orcid":"","institution":"Technical University of Denmark","correspondingAuthor":true,"prefix":"","firstName":"Mikkel","middleName":"Aaby","lastName":"Kruse","suffix":""},{"id":559574935,"identity":"5a9edb68-b284-4ad2-87dd-d2f510ad98de","order_by":1,"name":"Nanna Bjørnholt Karlsson","email":"","orcid":"","institution":"Geological Survey of Denmark and Greenland","correspondingAuthor":false,"prefix":"","firstName":"Nanna","middleName":"Bjørnholt","lastName":"Karlsson","suffix":""},{"id":559574937,"identity":"36a91b44-c0c7-4581-a3ab-3f5914fbb173","order_by":2,"name":"Penelope How","email":"","orcid":"","institution":"Geological Survey of Denmark and Greenland","correspondingAuthor":false,"prefix":"","firstName":"Penelope","middleName":"","lastName":"How","suffix":""},{"id":559574939,"identity":"a93f392c-444b-4af6-8627-8a695329640a","order_by":3,"name":"Anders Kusk","email":"","orcid":"","institution":"Technical University of Denmark","correspondingAuthor":false,"prefix":"","firstName":"Anders","middleName":"","lastName":"Kusk","suffix":""},{"id":559574942,"identity":"f26eb042-836e-451f-9bf3-5128fd350b79","order_by":4,"name":"Karina Nielsen","email":"","orcid":"","institution":"Technical University of Denmark","correspondingAuthor":false,"prefix":"","firstName":"Karina","middleName":"","lastName":"Nielsen","suffix":""},{"id":559574943,"identity":"3ea60204-f359-4c10-9b15-2f77822fedcb","order_by":5,"name":"Magdalena Łucka","email":"","orcid":"","institution":"AGH University of Krakow","correspondingAuthor":false,"prefix":"","firstName":"Magdalena","middleName":"","lastName":"Łucka","suffix":""},{"id":559574946,"identity":"089ccf41-938d-4ffa-99bd-87cf6ec98f82","order_by":6,"name":"Louise Sandberg Sørensen","email":"","orcid":"","institution":"Technical University of Denmark","correspondingAuthor":false,"prefix":"","firstName":"Louise","middleName":"Sandberg","lastName":"Sørensen","suffix":""}],"badges":[],"createdAt":"2025-11-27 22:53:07","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8225226/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8225226/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":98194756,"identity":"343f0bf3-4921-44e3-87d7-1a6a1bad18b4","added_by":"auto","created_at":"2025-12-15 06:32:05","extension":"json","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":9404,"visible":true,"origin":"","legend":"","description":"","filename":"89f516ae8e0d4ca7a06eab411270fef7.json","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/e69be8118cca04e44974eb85.json"},{"id":98432603,"identity":"f6c618fe-6965-4768-b8a7-fe947d7d1350","added_by":"auto","created_at":"2025-12-17 16:49:44","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":74522,"visible":true,"origin":"","legend":"","description":"","filename":"CoverLetter.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/d23f2b4b9e28241da8513ef8.pdf"},{"id":98432418,"identity":"19a1ab44-f753-4b56-805f-a1ddf8215822","added_by":"auto","created_at":"2025-12-17 16:49:32","extension":"pdf","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1274207,"visible":true,"origin":"","legend":"","description":"","filename":"Figure1.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/ed6bbcef55aa569bc33c78ea.pdf"},{"id":98194759,"identity":"5e9ab199-b7d2-48ba-95a0-94bdd780ec41","added_by":"auto","created_at":"2025-12-15 06:32:05","extension":"pdf","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":85615,"visible":true,"origin":"","legend":"","description":"","filename":"Figure2.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/5b6c725f5023a151ce68a332.pdf"},{"id":98194757,"identity":"2e964544-6c2b-412b-8147-48c2673a1912","added_by":"auto","created_at":"2025-12-15 06:32:05","extension":"pdf","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":40425,"visible":true,"origin":"","legend":"","description":"","filename":"Figure3.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/ae72fcd7f87e15b0a9ac51ef.pdf"},{"id":98194760,"identity":"0b0a3f4a-482f-41b7-9865-22b98ff3d66f","added_by":"auto","created_at":"2025-12-15 06:32:05","extension":"pdf","order_by":5,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":2801305,"visible":true,"origin":"","legend":"","description":"","filename":"Figure4.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/0f57c5dd026ae320b44359c8.pdf"},{"id":98194771,"identity":"978988aa-07b5-4621-951d-7f8dce711d05","added_by":"auto","created_at":"2025-12-15 06:32:06","extension":"pdf","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":20262772,"visible":true,"origin":"","legend":"","description":"","filename":"SupportingInformation.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/80405b8358746d83ed82d5a7.pdf"},{"id":98194762,"identity":"b3f35870-9674-43d9-802d-cbec8eb1c255","added_by":"auto","created_at":"2025-12-15 06:32:05","extension":"ldf","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":49107,"visible":true,"origin":"","legend":"","description":"","filename":"jabbrvltwaall.ldf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/ca89385bbd5d80ea6419ab26.ldf"},{"id":98194763,"identity":"73f84c52-18d8-4227-b9a4-85aaf71ff5fb","added_by":"auto","created_at":"2025-12-15 06:32:05","extension":"ldf","order_by":8,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":268657,"visible":true,"origin":"","legend":"","description":"","filename":"jabbrvltwaen.ldf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/0328b27dd85a0ecfd206729f.ldf"},{"id":98432568,"identity":"4dc179bb-0e3b-40ce-9a1a-d91a71c1324b","added_by":"auto","created_at":"2025-12-17 16:49:42","extension":"sty","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":15480,"visible":true,"origin":"","legend":"","description":"","filename":"jabbrv.sty","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/21e0573d60da1fb01cf2ba1d.sty"},{"id":98194768,"identity":"d81d7db8-7b88-41ac-b1ec-d2c1c8d8d355","added_by":"auto","created_at":"2025-12-15 06:32:05","extension":"bbl","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":28339,"visible":true,"origin":"","legend":"","description":"","filename":"main.bbl","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/48747de04e7faf4a4855f05d.bbl"},{"id":98194766,"identity":"5e82854b-5d8e-4001-9c7a-59c2e0ec20c5","added_by":"auto","created_at":"2025-12-15 06:32:05","extension":"bst","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":36153,"visible":true,"origin":"","legend":"","description":"","filename":"naturemagdoi.bst","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/6a7f5c0206a514d9b444f98c.bst"},{"id":98431994,"identity":"7bfec5c9-a3de-427c-a4e4-f079b54a1e31","added_by":"auto","created_at":"2025-12-17 16:48:46","extension":"pdf","order_by":12,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":4351481,"visible":true,"origin":"","legend":"","description":"","filename":"qqtnpbrjcbryppcqyscpnhccsjgrqcmr.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/45098c4ddbaa768dc8e82442.pdf"},{"id":98432940,"identity":"6e713991-e212-4ccd-bae5-c8b9ba8c6d71","added_by":"auto","created_at":"2025-12-17 16:50:07","extension":"cls","order_by":13,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":5824,"visible":true,"origin":"","legend":"","description":"","filename":"wlscirep.cls","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/46e64efcfaab9d100466fd4a.cls"},{"id":98194765,"identity":"bc261f0c-0d11-488a-84ef-b88301b16d9a","added_by":"auto","created_at":"2025-12-15 06:32:05","extension":"xml","order_by":14,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":84710,"visible":true,"origin":"","legend":"","description":"","filename":"89f516ae8e0d4ca7a06eab411270fef71structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/ad212ec68d3f1a1c6a67ece5.xml"},{"id":98444916,"identity":"aaf67749-065f-4feb-899b-6215ad084b7f","added_by":"auto","created_at":"2025-12-17 17:18:15","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2407599,"visible":true,"origin":"","legend":"","description":"","filename":"qqtnpbrjcbryppcqyscpnhccsjgrqcmr.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1_covered_a2b62f93-3e65-4b6f-b018-a1333dbdcd18.pdf"},{"id":98432019,"identity":"41e7796f-ab41-417d-bb11-0c3ef93c9a6d","added_by":"auto","created_at":"2025-12-17 16:48:52","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":20262772,"visible":true,"origin":"","legend":"","description":"","filename":"SupportingInformation.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8225226/v1/35e2d7ab3dd36ead1938f9e5.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Previously undocumented subglacial lake beneath Flade Isblink stores most of catchment runoff and delays its release","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8225226/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8225226/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"We report the discovery of a previously undocumented subglacial lake beneath the Flade Isblink Ice Cap in North East Greenland. Using satellite Earth Observation data from 2019 to 2025 and outputs from a regional climate model, we quantify the lake’s role in regional hydrology. The subglacial lake’s volume is characterised by an annual cycle of filling during the melt season and drainage in September-October, with the lake storing up to 74% of the yearly runoff from its catchment area. In most years, lake drainage causes a 2–3-month lag between peak surface-meltwater production and downstream discharge into the nearby proglacial lake, Romer Sø. Lake drainage occurred in all years in our observation period except 2022, which had the lowest surface melt rates, suggesting that a minimum water input threshold is required to initiate lake drainage. Additionally, we find that the lake is not hydrologically connected to the nearby, well-known subglacial lake on the high plateau of FladeIsblink. Our findings highlight how subglacial conditions may substantially modify the outflow of subglacial water to the ice margin with potential impacts on downstream hydrology and ecosystems. It further demonstrates the potential of integrating remote sensing with hydrological modelling to understand ice-sheet hydrology.","manuscriptTitle":"Previously undocumented subglacial lake beneath Flade Isblink stores most of catchment runoff and delays its release","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-15 06:32:00","doi":"10.21203/rs.3.rs-8225226/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-01-14T14:33:24+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-22T16:28:02+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"217723105500265438842615454941385866390","date":"2025-12-17T18:20:49+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-17T08:41:48+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"177579642063779170597980898870519241211","date":"2025-12-16T07:05:57+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"313738241363746406302821154813464571862","date":"2025-12-10T13:13:38+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-12-10T12:23:13+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-12-09T11:44:46+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-05T13:48:36+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-05T13:46:58+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2025-11-27T22:39:15+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"57f5bd7d-8831-4492-b329-c4cc27dc95b3","owner":[],"postedDate":"December 15th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[{"id":59576360,"name":"Earth and environmental sciences/Climate sciences"},{"id":59576361,"name":"Earth and environmental sciences/Environmental sciences"},{"id":59576362,"name":"Earth and environmental sciences/Hydrology"}],"tags":[],"updatedAt":"2026-05-08T03:53:47+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-15 06:32:00","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8225226","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8225226","identity":"rs-8225226","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}