More Like this

1. Long-term ice phenology records spanning up to 578 years for 78 lakes around the Northern Hemisphere

   https://doi.org/10.1038/s41597-022-01391-6  

   Sharma, Sapna; Filazzola, Alessandro; Nguyen, Thi; Imrit, M. Arshad; Blagrave, Kevin; Bouffard, Damien; Daly, Julia; Feldman, Harley; Feldsine, Natalie; Hendricks-Franssen, Harrie-Jan; et al (December 2022, Scientific Data)

   Abstract In recent decades, lakes have experienced unprecedented ice loss with widespread ramifications for winter ecological processes. The rapid loss of ice, resurgence of winter biology, and proliferation of remote sensing technologies, presents a unique opportunity to integrate disciplines to further understand the broad spatial and temporal patterns in ice loss and its consequences. Here, we summarize ice phenology records for 78 lakes in 12 countries across North America, Europe, and Asia to permit the inclusion and harmonization of in situ ice phenology observations in future interdisciplinary studies. These ice records represent some of the longest climate observations directly collected by people. We highlight the importance of applying the same definition of ice-on and ice-off within a lake across the time-series, regardless of how the ice is observed, to broaden our understanding of ice loss across vast spatial and temporal scales. 

   more » « less
2. Impacts of Changing Winters on Lake Ecosystems Will Increase With Latitude

   https://doi.org/10.1111/ele.70200  

   Ozersky, Ted; Poste, Amanda; Rautio, Milla; Leu, Eva (August 2025, Ecology Letters)

   ABSTRACT Climate warming is especially pronounced in winter and at high latitudes. Warming winters are leading to the loss of lake ice and changing snow cover on lakes. Historically, lake scientists have paid less attention to the ice cover period, leading to data and theory gaps about the role of winter conditions in lake ecosystem function and the consequences of changing winters. Here we use simple models to show that the latitudinal interaction between ice cover duration and light flux seasonality has profound and underappreciated implications for lakes. Our models focus on light and temperature, two key drivers of ecosystem processes. We show that the relative amount of light arriving in lakes during ice cover increases non‐linearly with latitude and that the light climate of high latitude lakes is much more sensitive to changing winter conditions than that of lower latitude lakes. We also demonstrate that the synchronicity between high light and warm temperatures may decrease with latitude, with implications for primary and secondary production. Our results suggest that ice loss may lead to greater relative change to productivity and biotic interactions in higher latitude lakes and also offer several testable predictions for understanding the consequences of climate‐induced changes across latitudinal gradients. 

   more » « less
3. Shorter Ice Duration and Changing Phenology Influence Under‐Ice Lake Temperature Dynamics

   https://doi.org/10.1029/2024JG008382  

   Oleksy, Isabella A; Richardson, David C (November 2024, Journal of Geophysical Research: Biogeosciences)

   Abstract Temperate lakes worldwide are losing ice cover but the implications for under‐ice thermal dynamics are poorly constrained. Using a 92‐year record of ice phenology from a temperate and historically dimictic lake, we examined trends, variability, and drivers of ice phenology and under‐ice temperatures. The onset of ice formation decreased by 23 days century⁻¹, which can be largely attributed to warming air temperatures. Ice‐off date has become substantially more variable with spring air temperatures and cumulative February through April snowfall explaining over 80% of the variation in timing. As a result of changing ice phenology, total ice duration contracted by a month and more than doubled in interannual variability. Using weekly under‐ice temperature profiles for the most recent 36 years, we found that shorter ice duration decreased winter inverse stratification and was associated with an extended spring mixing period. We illustrate the limitations of relying on discrete ice clearance dates in our assumptions around under‐ice thermal dynamics by presenting high‐frequency under‐ice observations in two recent winters: one with intermittent ice cover and a year with slow spring ice clearance. 

   more » « less
4. Modeling present and future ice covers in two Antarctic lakes

   https://doi.org/10.1017/jog.2019.78  

   Echeverría, Sebastián; Hausner, Mark B.; Bambach, Nicolás; Vicuña, Sebastián; Suárez, Francisco (February 2020, Journal of Glaciology)

   Abstract Antarctic lakes with perennial ice covers provide the opportunity to investigate in-lake processes without direct atmospheric interaction, and to study their ice-cover sensitivity to climate conditions. In this study, a numerical model – driven by radiative, atmospheric and turbulent heat fluxes from the water body beneath the ice cover – was implemented to investigate the impact of climate change on the ice covers from two Antarctic lakes: west lobe of Lake Bonney (WLB) and Crooked Lake. Model results agreed well with measured ice thicknesses of both lakes (WLB – RMSE= 0.11 m over 16 years of data; Crooked Lake – RMSE= 0.07 m over 1 year of data), and had acceptable results with measured ablation data at WLB (RMSE= 0.28 m over 6 years). The differences between measured and modeled ablation occurred because the model does not consider interannual variability of the ice optical properties and seasonal changes of the lake's thermal structure. Results indicate that projected summer air temperatures will increase the ice-cover annual melting in WLB by 2050, but that the ice cover will remain perennial through the end of this century. Contrarily, at Crooked Lake the ice cover becomes ephemeral most likely due to the increase in air temperatures. 

   more » « less
5. Eutrophication and ice phenology influence methane storage in north temperate lakes

   https://doi.org/10.1002/lol2.70136  

   Wilkinson, Grace M; McCarthy, Moira; Bertolet, Brittni; Carpenter, Stephen R; Ha, Dat; Lottig, Noah; Szydlowski, Daniel K; Pace, Michael L; Jones, Stuart (May 2026, Limnology and Oceanography Letters)

   Abstract Among lakes, eutrophication is positively related to methane emissions, but various processes can alter the seasonal conversion of primary production into stored methane. We used a series of whole‐lake enrichment and shading experiments across three years with varying ice phenology to assess how eutrophication and ice cover affect within‐year methane storage. The seasonal pattern of methane storage was driven in part by cyanobacteria blooms and their influence on light and oxygen availability. Early ice‐off reduced anoxic volume and methane storage in both the manipulated and reference lake, but a subsequent bloom and shading in the manipulated lake drove a rapid increase in methane, with storage reaching similar levels to those of other years. These experiments revealed that interactions between ice phenology and eutrophication can drive shifts in seasonal methane storage trajectories in north temperate lakes. Improved understanding of variability in these drivers could substantially reduce uncertainty in lake methane emissions. 

   more » « less