Historical Trends, Drivers, and Future Projections of Ice Phenology in Small North Temperate Lakes in the Laurentian Great Lakes Region

Abstract

Lake ice phenology (timing of ice breakup and freeze up) is a sensitive indicator of climate. We acquired time series of lake ice breakup and freeze up, local weather conditions, and large-scale climate oscillations from 1981-2015 for seven lakes in northern Wisconsin, USA, and two lakes in Ontario, Canada. Multiple linear regression models were developed to understand the drivers of lake ice phenology. We used projected air temperature and precipitation from 126 climate change scenarios to forecast the day of year of ice breakup and freeze up in 2050 and 2070. Lake ice melted 5 days earlier and froze 8 days later over the past 35 years. Warmer spring and winter air temperatures contributed to earlier ice breakup; whereas warmer November temperatures delayed lake freeze. Lake ice breakup is projected to be 13 days earlier on average by 2070, but could vary by 3 days later to 43 days earlier depending upon the degree of climatic warming by late century. Similarly, the timing of lake freeze up is projected to be delayed by 11 days on average by 2070, but could be 1 to 28 days later. Shortened seasonality of ice cover by 24 days could increase risk of algal blooms, reduce habitat for coldwater fisheries, and jeopardize survival of northern communities reliant on ice roads.

The unique methodological challenges of winter limnology

“…With growing technological improvements and a greater interest in winter limnology, we expect rapid development of more creative methods to study lakes under the ice. Ultimately, increased winter sampling will provide a more comprehensive understanding of how aquatic ecosystems function, particularly in light of changing winter conditions (Magnuson et al ; Jensen et al ; Hewitt et al ). In addition, continued active dialog will help develop creative new methods, lower barriers for researchers to initiate winter work, and facilitate integrative and comparative winter studies across globally distributed lakes.…”

River and Lake Ice Processes—Impacts of Freshwater Ice on Aquatic Ecosystems in a Changing Globe

“…Climate change effects must be viewed through a regional lens, understanding the specific types of changes in precipitation, temperature, wind, and other variables that may occur, and building an understanding of how that will affect the ecosystems in a region. To help build the necessary local-regional-global understanding, synthetic work to understand differences across watersheds, across lakes, across rivers, and across regions such as those already presented here [32,62,64] and elsewhere [3,9] is very valuable-identifying common responses of ecosystems through winter, and differences across regions, and across types of lakes and rivers. This type of comparative approach will help to build a more diverse, regionally-informed understanding of physical, hydrological, hydraulic, biogeochemical, and ecological change, particularly when coupled with work to inform process-based understanding of changes through winter (e.g., [10,12]), and to integrate our growing understanding of winter changes into model-based frameworks (e.g., [76][77][78]).…”

“…Lakes and rivers are already experiencing decreased ice-cover duration in many regions [24,28,29], with the largest impact of climate change on ice-cover duration expected to be a much earlier spring melt, up to four-weeks earlier by 2050 [30,31]. Work by Hewitt et al [32] presented here compares long-term breakup and freezeup records over nine lakes in Wisconsin USA, and Ontario, Canada. They demonstrate that over 35 years, there has been a shift to loss of ice cover five days earlier in spring, and freeze up eight days later, associated with warmer fall, winter, and spring temperatures.…”

“…These changes have already been observed in some areas of the world, including in Lake Erie, and Sweden [18,63,69], and in some cases, resulting in increased spring bloom diatom biomass causing water quality problems for local municipalities [63]. Warner et al have provided important insights that will help build an understanding of the different responses we might anticipate across lakes of different regions, building on some of our knowledge of different physical responses, for example among lakes with varied mean depths [32]. Parks et al [70,71] also found that river ice in the arctic is lessening due to regional climate warming, as are other components of the cryosphere such as permafrost, glacier ice, and sea ice.…”

Consequences of lake and river ice loss on cultural ecosystem services

“…As a result of climate change, shorter ice duration or incomplete ice cover are becoming more common around the world (Magnuson et al ; Benson et al ; Sharma et al ). Projected trends for air temperature and snow cover in the Northern Hemisphere suggest that seasonal ice cover duration will continue to decline (Shuter et al ; Yao et al ; Magee and Wu ; Hewitt et al ; Sharma et al ).…”