An Introduction to the Community Lake Ice Collaboration: A Long-Term Lake Ice Phenology Community Science Project Spanning 1000 Lakes and Over 30 Years

For northern communities, ice cover is intrinsically linked to life in winter. Transportation, recreation, provisioning of food and ice, and religious ceremonies are only some of the ways people use lake ice (Knoll et al. 2019). For example, winter ice roads provide critical transportation infrastructure for remote communities in the Arctic to ship food, fuel, and medical supplies, in addition to employment and social networks over the dark, cold winters (Hori et al. 2017). Countless kids across Canada, Sweden, Russia, and countries across the Northern Hemisphere have learned how to skate and play hockey at local frozen lakes and ponds. Millions of people attend ice festivals around the world each winter, with the Harbin International Ice and Snow festival in China being the largest, attracting 18 million visitors and producing $4.4 billion in revenue annually (https://www.hindustantimes.com/travel/theworld-s-largest-ice-festival-features-massivestunning-sculptures-see-pics/story-b9g0rNY56 ylYRlgK3Y2FnI.html, accessed on 20 January 2023; www.icefestivalharbin.com, accessed on 20 January 2023). Last but not least, ice fishing provides a source of recreation, and also protein sources, to northern communities. For example, a large retired and unemployed community angle for perch, roach, and ruffe in the frozen Lake Peipsi (Russia, Estonia, Latvia) and sell their catch to their local community over the winter (Orru et al. 2014). Because of the large importance of lake ice to northern communities, long-term observations of ice records spanning decades to centuries exist for lakes and rivers around the world (Magnuson et al. 2000). Warmer winters are contributing to the loss of lake ice and the consequential decline in winter lake ice activities (Magnuson et al. 2000; Knoll et al. 2019). Lakes are losing their ice cover at alarming rates owing to anthropogenic emissions of greenhouse gas emissions (Sharma et al. 2021b) with unprecedented rates of ice loss expected by the end of the 21 century (Sharma et al. 2019). For example, in the last 25 years, lakes have been observed losing ice at rates of 107 days per century, at rates six times faster than any other time period in the last 100 years (Sharma et al. 2021b). Lakes that froze reliably every winter are now beginning to experience ice-free winters (Sharma et al. 2019), with some of these lakes forecasted to permanently lose ice cover within this century if greenhouse gas emissions are not mitigated (Sharma et al. 2021a). Large, deep lakes in colder regions, in addition to small and large lakes found in regions where winter air temperatures hover below 0 C, such as in coastal, low-elevation, or more southerly regions, are at highest risk of ice-free winters (Sharma et al. 2019, 2021a). Lakes in the contiguous states of the United States of America are one of the most vulnerable regions to losing ice cover within this century (Sharma et al. 2019). We currently have updated records for handfuls of lakes across Wisconsin, Minnesota, New York, New Hampshire, and Maine within the Global Lake and River Ice Phenology database housed at the National Snow and Ice Data Centre based on long-term human observations (Benson et al. 2000, updated 2021; Sharma et al. 2022). However, we currently lack observations for smaller and shallow lakes across a landscape. Fortuitously, Kenton Stewart, an emeritus professor from the University at Buffalo, USA, established the Community Lake Ice Collaboration (CLIC) in the 1980s collecting lake ice phenological observations for hundreds of lakes across the United States (Fig. 1). Kenton Stewart passed on the reins of his community science project to his former Ph.D. student, Gerald Bove, and then Sapna Sharma at York University in Toronto, Canada, who is now the lead. As this project is transitioning to new leadership, it is a good opportunity to share the history behind the development of this long-term community science project on a tight budget. The CLIC was established in the 1980s by Kenton Stewart from the University at Buffalo, USA. CLIC evolved out of work which started in 1967, specifically the long-term limnological monitoring of the Western Finger Lakes in New York, USA. At the start of the study on the Western Finger Lakes, real-time local weather and lake data were not readily available. As the Finger Lakes were 100+ km from the Buffalo campus, a phone call to local “lake monitors” helped to identify if conditions were favorable for sampling, including whether the lakes were still ice-covered. Stewart recruited lake monitors by direct outreach to marinas, local chambers of commerce, and state conservation officers. In other instances, curious passersby encountered while sampling were also recruited. Lake monitors lived or worked near the study lakes and were called on a monthly or bimonthly basis, enabling researchers to gather information on local conditions prior to making the hours-long trip from the university. For the first few years of monitoring the Western Finger Lakes, freeze/thaw dates were estimated based on lakes being frozen or open during the bi-monthly visits. However, with the establishment of lake monitors, exact dates for freeze/thaw could be recorded remotely. Some of the more curious participants asked to join in field sampling and some provided material support for the project, including storage spaces for equipment. By the mid-1980s, visits to the Finger Lakes by the lake monitors numbered in the hundreds. From the researchers’ perspective, the local knowledge that lake monitors provided was invaluable to conducting the study. However, over time, there was also a sense of connection and community that developed around a common interest, an essential element in sustaining long-term participation in a project (Rotman et al. 2014). Once lake monitors were recruited, they were dedicated and increasingly interested in observing and reporting lake conditions; it appeared that the observations were benefiting both the lake monitors and the researchers. The lake monitors were noticing and recording events that they may have only observed by chance before, and the researchers were efficiently gathering important data. The “success” of the lake monitors in the Finger Lakes led to monitors being recruited at other regularly sampled lakes in New York and Wisconsin (during family visits by the founder, Stewart) to collect freeze and thaw dates. From this point, monitors were recruited in other states where Stewart had worked or had personal or professional contacts, including Maine, Minnesota, and Michigan. Lake monitors were recruited in these areas using a similar methodology to that of New York and Wisconsin. Stewart first reached out to personal and professional contacts, followed by sourcing phone numbers of