Article
Multidisciplinary Sciences
Kyle S. S. Mattingly, Jenny V. V. Turton, Jonathan D. D. Wille, Brice Noel, Xavier Fettweis, Asa K. Rennermalm, Thomas L. L. Mote
Summary: The Greenland Ice Sheet has been melting at an accelerated rate, particularly in northeast Greenland. The extreme melt events in this region are mainly caused by atmospheric rivers (ARs) from northwest Greenland, which induce foehn winds in the northeast. These events have become more frequent in the twenty-first century and are expected to continue increasing with climate warming.
NATURE COMMUNICATIONS
(2023)
Article
Geosciences, Multidisciplinary
D. Tonina, A. Marzadri, A. Bellin, M. M. Dee, S. Bernal, J. L. Tank
Summary: The study demonstrates that riverine N2O emissions decrease with increasing low flow severity, regardless of dissolved inorganic reactive nitrogen (DIN) concentrations, providing a form of climate resilience.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Water Resources
Ada Pastor, Louis J. Skovsholt, Kirsten S. Christoffersen, Naicheng Wu, Tenna Riis
Summary: This study investigates the impact of climate change on stream biogeochemistry in the Arctic, finding that vegetation and geomorphology have contrasting effects on stream hydrochemistry. High-Arctic catchments are facing changes in vegetation cover and soil physical disturbance due to climate change, which will affect stream productivity and solute export.
HYDROLOGICAL PROCESSES
(2021)
Article
Multidisciplinary Sciences
Laura A. Stevens, Meredith Nettles, James L. Davis, Timothy T. Creyts, Jonathan Kingslake, Ian J. Hewitt, Aaron Stubblefield
Summary: The impact of increasing surface melt on the annual discharge of the Greenland Ice Sheet is unclear. Observations of a supraglacial lake drainage at Helheim Glacier show that basal floods following these events have limited effect on ice flow. The discharge of the ice sheet to the ocean is mainly controlled by fast-flowing outlet glaciers, and the influence of increasing surface melt on annual discharge is still unknown.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Mathis Loic Messager, Bernhard Lehner, Charlotte Cockburn, Nicolas Lamouroux, Herve Pella, Ton Snelder, Klement Tockner, Tim Trautmann, Caitlin Watt, Thibault Datry
Summary: Flowing waters play a crucial role in supporting global biodiversity, biogeochemical cycles, and human societies. However, the prevalence and significance of non-perennial rivers and streams are often overlooked, contributing to the degradation of water sources and livelihoods. By analyzing global data, it was found that a significant portion of the world's rivers experience at least one day of flow cessation each year, challenging traditional river concepts and highlighting the importance of considering intermittence in river management.
Article
Water Resources
Dongyu Zhu, Chunxia Zhou, Yikai Zhu, Boyang Peng
Summary: This study investigates the Supraglacial lakes (SGLs) of Sermeq Avannarleq glacier in southwest Greenland and analyzes the seasonal changes of these lakes from 2000 to 2020 using satellite images. The results show an increase in the area, volume, and depth of the lakes, as well as changes in the melting area and elevation.
JOURNAL OF HYDROLOGY-REGIONAL STUDIES
(2022)
Review
Biodiversity Conservation
Francine H. Mejia, Valerie Ouellet, Martin A. Briggs, Stephanie M. Carlson, Roser Casas-Mulet, Mollie Chapman, Mathias J. Collins, Stephen J. Dugdale, Joseph L. Ebersole, Danielle M. Frechette, Aimee H. Fullerton, Carole-Anne Gillis, Zachary C. Johnson, Christa Kelleher, Barret L. Kurylyk, Rebecca Lave, Benjamin H. Letcher, Knut M. Myrvold, Tracie-Lynn Nadeau, Helen Neville, Herve Piegay, Kathryn A. Smith, Diego Tonolla, Christian E. Torgersen
Summary: Human activities and climate change have negative impacts on coldwater organisms in freshwater ecosystems by warming rivers and streams, increasing warm temperature events, and reducing thermal heterogeneity. It is crucial to adopt cohesive management approaches to protect cold-water refuges, considering physical, biological, and social factors. Current policies for protecting thermally sensitive species include designating cold-water habitats, restricting fishing during warm periods, and implementing temperature standards or guidelines. However, these policies lack coordination and Indigenous peoples' input. We propose managing cold-water refuges as distinct operational landscape units, integrating science and management to prioritize actions and implement adaptive practices.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Geography, Physical
Rohi Muthyala, Asa K. Rennermalm, Sasha Z. Leidman, Matthew G. Cooper, Sarah W. Cooley, Laurence C. Smith, Dirk van As
Summary: This study presents long-term discharge data for a supraglacial stream catchment in southwest Greenland, capturing diurnal and seasonal variability. Shortwave radiation is the primary driver of melting, but its contribution decreases during high-melt episodes, while longwave radiation, sensible heat fluxes, and latent heat fluxes become more important. The timing of daily maximum discharge changes, possibly due to the expansion and contraction of the stream network.
Article
Environmental Sciences
Wensong Zhang, Kang Yang, Laurence C. Smith, Yuhan Wang, Dirk van As, Brice Noe, Yao Lu, Jinyu Liu
Summary: This study investigates the spatiotemporal distribution and variability of surface water in Greenland using Sentinel-2 imagery and model simulations. The results show significant differences in surface water extent, volume, and drainage pattern between different years and regions, with supraglacial rivers playing a dominant role in surface water appearance.
REMOTE SENSING OF ENVIRONMENT
(2023)
Article
Geography, Physical
Kang Yang, Laurence C. Smith, Matthew G. Cooper, Lincoln H. Pitcher, Dirk van As, Yao Lu, Xin Lu, Manchun Li
Summary: The study found that at elevations above 1600 meters, 21% of supraglacial lakes and 28% of supraglacial rivers drain into moulins, even during a colder-than-average melt season; supraglacial lakes dominate instantaneous surface meltwater storage, while supraglacial rivers dominate total surface meltwater area and discharge; the combined surface area of supraglacial lakes and rivers is strongly correlated with modeled surface runoff; among the three models examined, MERRA-2 runoff yields the highest overall correlation with observed proglacial discharge in the Watson River.
JOURNAL OF GLACIOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Paolo Billi, Velibor Spalevic
Summary: This study utilized suspended sediment yield field data measured by the national and regional hydrological services to investigate the factors influencing sediment yield in Italy. The research found a wide variation in sediment yield and attributed the marked decrease in sediment yield in Italy to factors such as reduced annual precipitation and forest expansion.
Article
Engineering, Civil
Yao Lu, Kang Yang, Xin Lu, Ya Li, Shuai Gao, Wei Mao, Manchun Li
Summary: This study mapped the supraglacial rivers and lakes on the northeast Greenland Ice Sheet, finding that they cover a significant area, are influenced by regional climate and ice flow regimes, and their morphology is controlled by surface meltwater and ice flow.
JOURNAL OF HYDROLOGY
(2021)
Article
Geosciences, Multidisciplinary
Sasha Z. Leidman, Asa K. Rennermalm, Rohi Muthyala, Qizhong Guo, Irina Overeem
Summary: Melting on the Greenland Ice Sheet leads to the formation of extensive supraglacial stream networks, which accumulate low-albedo sediments and contribute to further melting disproportionately. Studies analyzing the distribution of these sediments and their hydrodynamic properties are rare. Experimental results suggest that without microbial growth-induced flocculation, sediments would be flushed out, resulting in significantly higher albedos of supraglacial streams.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
David M. Chandler, Alun Hubbard
Summary: Dramatic supraglacial lake drainage events in Greenland and Antarctica are caused by fast hydrofracture propagation, but this study presents a slower mode of hydrofracture where hairline fractures intersect supraglacial streams. They suggest that water supply and englacial refreezing are critical factors limiting penetration depth. The study proposes that stream-driven hydrofractures are widespread across Greenland and Antarctica's ablation zones, and have significant impacts on englacial thermal profiles and the vulnerability of ice sheets and shelves to dynamic instability.
Review
Ecology
Christopher J. Sullivan, Jason C. Vokoun, Ashley M. Helton, Martin A. Briggs, Barret L. Kurylyk
Summary: The concept of thermal refuges is vague and often used interchangeably, hindering a holistic understanding. A structured framework is needed to define and measure thermal refuge types.
Article
Geography, Physical
Asa K. Rennermalm, Regine Hock, Federico Covi, Jing Xiao, Giovanni Corti, Jonathan Kingslake, Sasha Z. Leidman, Clement Miege, Michael Macferrin, Horst Machguth, Erich Osterberg, Takao Kameda, Joseph R. McConnell
Summary: Research shows that the firn density on the Greenland ice sheet has increased in the past few decades, but some areas have experienced a decrease in density after an extreme melt in 2012. This suggests that despite overall melting increases, temporary build-up in firn pore space and meltwater infiltration capacity may still occur in certain regions.
JOURNAL OF GLACIOLOGY
(2022)
Article
Fisheries
David A. Boughton, Lee R. Harrison, Sara N. John, Rosealea M. Bond, Colin L. Nicol, Carl J. Legleiter, Ryan T. Richardson
Summary: The study used high-resolution methods to assess the capacity for anadromous steelhead and spring-run Chinook Salmon reintroduction in the Tuolumne and Merced rivers in the Sierra Nevada of California. Results showed that both systems could support viable populations of these species, with the Merced River being too warm for adult Chinook Salmon in the dry season.
TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY
(2022)
Article
Geosciences, Multidisciplinary
Kang Yang, Laurence C. Smith, Lauren C. Andrews, Xavier Fettweis, Manchun Li
Summary: There is a positive correlation between supraglacial drainage efficiency (D-d) and surface meltwater runoff (R) on the southwestern Greenland Ice Sheet. High-resolution satellite images can be used to map the spatial and temporal changes in D-d throughout the melt season, improving the characterization of supraglacial drainage efficiency.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2022)
Article
Multidisciplinary Sciences
J. C. Ryan, L. C. Smith, S. W. Cooley, B. Pearson, N. Wever, E. Keenan, J. T. M. Lenaerts
Summary: This study shows that clouds will play an increasingly important role in determining the Greenland Ice Sheet's contribution to global sea levels. The decrease in albedo in the ablation zone will make radiative fluxes more sensitive to changes in cloudiness, making accurate representation of clouds crucial for forecasting the ice sheet's impact on sea-level rise.
NATURE COMMUNICATIONS
(2022)
Article
Environmental Sciences
Ethan D. Kyzvat, Laurence C. Smith, Fenix Garcia-Tigreros, Chang Huang, Chao Wang, Theodore Langhorst, Jessica Fayne, Merritt E. Harlan, Yuta Ishitsuka, Dongmei Feng, Wayana Dolan, Lincoln H. Pitcher, Kimberly P. Wickland, Mark M. Dornblaser, Robert G. Striegl, Tamlin M. Pavelsky, David E. Butman, Colin J. Gleason
Summary: Areas of lakes with emergent aquatic vegetation emit more methane than open water, but are often overlooked in estimates of lake methane emissions. Using airborne synthetic aperture radar (SAR) mapping and field measurements, we found that these vegetated areas are more extensive than previously estimated and exhibit regional differences. When these areas were accounted for, overall lake methane emissions increased compared to estimates that did not differentiate lake zones. This highlights the need for methane-relevant remote sensing measurements and a consistent criterion for distinguishing wetlands in lake studies.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2022)
Article
Geography, Physical
Chang Huang, Laurence C. Smith, Ethan D. Kyzivat, Jessica Fayne, Yisen Ming, Christopher Spence
Summary: Accurate mapping of wetland inundation in the boreal region is crucial for monitoring ecological and societal functions. This study develops a novel algorithm to track wetland inundation using satellite data and validates the results. The findings have significant implications for wetland function monitoring and methane emissions estimation.
GISCIENCE & REMOTE SENSING
(2022)
Article
Geosciences, Multidisciplinary
Jing Xiao, Asa K. Rennermalm, Federico Covi, Regine Hock, Sasha Z. Leidman, Clement Miege, Michael J. MacFerrin, Samira Samimi
Summary: The study investigates the local-scale variability in firn density and ice content in southwest Greenland using shallow firn cores. The results show that there is substantial local variability in density and ice content, especially in high-elevation sites. The study emphasizes the importance of considering local variability in regional analyses.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Environmental Sciences
Carl J. Legleiter, Paul J. Kinzel, Mark Laker, Jeffrey S. Conaway
Summary: Information on velocity fields in rivers is crucial for various applications. This study presents a framework for measuring river velocity using aerial images, which has been successfully tested in two Alaskan rivers.
WATER RESOURCES RESEARCH
(2023)
Article
Environmental Sciences
Carl J. Legleiter, Paul J. Kinzel
Summary: Accurate knowledge of water speed in rivers is vital for ecological and resource management purposes. Remote sensing is a more efficient method for measuring flow velocity, and powerful computational techniques have been developed for inferring velocity fields from videos or image time series. This paper introduces a software tool, TRiVIA, designed to facilitate the use of particle image velocimetry (PIV) by the river community. TRiVIA provides a complete workflow for producing spatially distributed velocity vectors from videos or images, with modules for data extraction, stabilization, enhancement, PIV analysis, visualization, accuracy assessment, and output export. The toolbox, now freely available, can be augmented to incorporate bathymetric information for discharge calculation functionality.
RIVER RESEARCH AND APPLICATIONS
(2023)
Article
Environmental Sciences
Bo Wang, Laurence C. Smith, Colin Gleason, Ethan D. Kyzivat, Jessica V. Fayne, Merritt E. Harlan, Theodore Langhorst, Dongmei Feng, Emily Eidam, Sebastian Munoz, Julianne Davis, Tamlin M. Pavelsky, Daniel L. Peters
Summary: Using in situ measurements and 37 years of satellite imagery, we have identified a slow avulsion of the Athabasca River in the Peace-Athabasca River Delta, Canada. This gradual channel change could have long-term implications for inundation patterns, ecosystems, and human use of the area.
WATER RESOURCES RESEARCH
(2023)
Article
Multidisciplinary Sciences
Kyle S. S. Mattingly, Jenny V. V. Turton, Jonathan D. D. Wille, Brice Noel, Xavier Fettweis, Asa K. Rennermalm, Thomas L. L. Mote
Summary: The Greenland Ice Sheet has been melting at an accelerated rate, particularly in northeast Greenland. The extreme melt events in this region are mainly caused by atmospheric rivers (ARs) from northwest Greenland, which induce foehn winds in the northeast. These events have become more frequent in the twenty-first century and are expected to continue increasing with climate warming.
NATURE COMMUNICATIONS
(2023)
Article
Geosciences, Multidisciplinary
Sasha Z. Leidman, Asa K. Rennermalm, Rohi Muthyala, S. McKenzie Skiles, Alexander Getraer
Summary: The presence of low-albedo features, such as water-filled supraglacial stream channels with cryoconite sediment, greatly contributes to the melting of the Greenland Ice Sheet. However, little is known about the spatial distribution of these sediment deposits and their response to seasonal flow regimes. This study surveyed a supraglacial stream network in Southwest Greenland, using UAV flights to collect imagery and digital elevation models. The findings show how sediment cover and stream width are correlated, and how changes in sediment cover affect albedo and the energy balance of the Ice Sheet surface.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Remote Sensing
Laurence C. Smith, Jessica V. Fayne, Bo Wang, Ethan D. Kyzivat, Colin J. Gleason, Merritt E. Harlan, Theodore Langhorst, Dongmei Feng, Tamlin M. Pavelsky, Daniel L. Peters
Summary: By analyzing the AirSWOT data in the PAD region of Canada, it is found that the SWOT technology can reveal water level changes and potential river avulsion. Although the AirSWOT data is noisy and susceptible to data losses, the river flow directions and water surface slope can still be accurately inferred after processing.
REMOTE SENSING LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Milad Niroumand-Jadidi, Carl J. Legleiter, Francesca Bovolo
Summary: This study evaluates the potential of using Landsat-9 imagery to map river bathymetry and finds that Landsat-9 provides more accurate bathymetry measurements, particularly when pan-sharpened. Additionally, downsampling SuperDove data and the enhanced spectral resolution of the 8-band SuperDoves improved depth retrieval. The neural network-based model outperformed the optimal band ratio analysis in bathymetry retrieval.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2022)
Article
Geography, Physical
Rohi Muthyala, Asa K. Rennermalm, Sasha Z. Leidman, Matthew G. Cooper, Sarah W. Cooley, Laurence C. Smith, Dirk van As
Summary: This study presents long-term discharge data for a supraglacial stream catchment in southwest Greenland, capturing diurnal and seasonal variability. Shortwave radiation is the primary driver of melting, but its contribution decreases during high-melt episodes, while longwave radiation, sensible heat fluxes, and latent heat fluxes become more important. The timing of daily maximum discharge changes, possibly due to the expansion and contraction of the stream network.