Polar bear sighting. (Credit: Valentina Ekimova)
Field Notes
By Valentina Ekimova | Sept/Oct 2025
Snow and Ice: Tracking Infrastructure Impact in Arctic Aquatic Systems
From 30 September to 7 October, Utqiaġvik, Alaska, greeted us with a surprise: about 3 inches of shorefast ice on our study sites. At the same time last year, these shores were only lightly iced even later in October, so this early, solid ice cover was not what we expected.Our targets were the same three water bodies, now in their early winter mode: Imikpuk Lake, Middle Salt Lagoon, and Isatkoak Lagoon. The method also stayed the same. Using a YSI EXO1 Multiparameter Sonde, we collected shoreline profiles of temperature, conductivity, dissolved oxygen, pH, turbidity, algal biomass, and fluorescent dissolved organic matter (fDOM) at locations influenced by roads and buildings as well as more tundra-dominated stretches.What changed was the effort required to reach the water. Instead of picking our way through slush and thin ice, we had to work through thick, resonant ice that echoed across Utqiaġvik with every hammer strike. Armed with a hammer and an ice breaker, and with support from our bear guard Emi, we opened holes through the ice at each sampling point. Emi not only kept an eye out after a recently visiting bear, but also helped us break through the ice so we could get the sonde into the water.The cold was not just an abstract metric; our instrument felt it too. The sonde started to freeze between measurements, so we treated it like a small, very valuable field companion, tucking it back into a warm, thermally insulated cover whenever it was out of the water.Despite the conditions, we completed our planned transects and came away with a full set of fall measurements that pair directly with our summer data. Together, these two years of summer and autumn records will allow us to explore how infrastructure and strong seasonality shape the chemistry and thermal structure of Arctic lakes and lagoons. I will share the results in an oral presentation at AGU 2025 in New Orleans, 15–19 December.