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Abstract Climate change is contributing to rapid changes in lake ice cover across the Northern Hemisphere, thereby impacting local communities and ecosystems. Using lake ice cover time‐series spanning over 87 yr for 43 lakes across the Northern Hemisphere, we found that the interannual variability in ice duration, measured as standard deviation, significantly increased in only half of our studied lakes. We observed that the interannual variability in ice duration peaked when lakes were, on average, covered by ice for about 1 month, while both longer and shorter long‐term mean ice cover duration resulted in lower interannual variability in ice duration. These results demonstrate that the ice cover duration can become so short that the interannual variability rapidly declines. The interannual variability in ice duration showed a strong dependency on global temperature anomalies and teleconnections, such as the North Atlantic Oscillation and El Niño–Southern Oscillation. We conclude that many lakes across the Northern Hemisphere will experience a decline in interannual ice cover variability and shift to open water during the winter under a continued global warming trend which will affect lake biological, cultural, and economic processes.
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Observation-derived ice growth curves show patterns and trends in maximum ice thickness and safe travel duration of Alaskan lakes and rivers
Abstract. The formation, growth, and decay of freshwater ice on lakes andrivers are fundamental processes of northern regions with wide-rangingimplications for socio-ecological systems. Ice thickness at the end ofwinter is perhaps the best integration of cold-season weather and climate,while the duration of thick and growing ice cover is a useful indicator forthe winter travel and recreation season. Both maximum ice thickness (MIT)and ice travel duration (ITD) can be estimated from temperature-driven icegrowth curves fit to ice thickness observations. We simulated and analyzedice growth curves based on ice thickness data collected from a range ofobservation programs throughout Alaska spanning the past 20–60 years tounderstand patterns and trends in lake and river ice. Results suggestreductions in MIT (thinning) in several northern, interior, and coastalregions of Alaska and overall greater interannual variability in riverscompared to lakes. Interior regions generally showed less variability in MITand even slightly increasing trends in at least one river site. Average ITDranged from 214 d in the northernmost lakes to 114 d acrosssouthernmost lakes, with significant decreases in duration for half ofsites. River ITD showed low regional variability but high interannualvariability, underscoring the challenges with predictingseasonally consistent river travel. Standardization and analysis of theseice observation data provide a comprehensive summary for understandingchanges in winter climate and its impact on freshwater ice services.
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- PAR ID:
- 10280457
- Date Published:
- Journal Name:
- The Cryosphere
- Volume:
- 14
- Issue:
- 11
- ISSN:
- 1994-0424
- Page Range / eLocation ID:
- 3595 to 3609
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.5194/tc-14-3595-2020
