Hydrophones Beneath River Ice

Two hydrophones (Aquarian H2d) hung from leafless branches and lodged under the ice in this narrow curving section of the Tromsdalselva / Sálášváhjohka river, just before the bridge leading from the stadium. Some ice sheets are starting to collapse, fragments drifting downstream. From observations from the bank, the thickness of the main sections of remaining ice around 3 cm.