A release device for a polar profile observation system includes a support frame, a release base, a control electronic cabin, a release mechanism, and a floating body. The support frame performs an up and down profile movement along the under-ice guide cable, and is bonded with the profile observation system before the profile observation system is released. The release base is configured to provide an installation platform for the release mechanism. The control electronic cabin is configured to receive a release signal sent by the profile observation system and enable the release mechanism. The release mechanism is configured to perform a release task, so that the profile observation system can be detached from the support frame. The floating body provides buoyancy to balance the gravity of the release device.

An adjustable tethering system is disclosed that includes a primary line, a secondary line, and a capsule. The secondary line is wound about the primary line to form a frictional locking arrangement that resists translation of the secondary line along the primary line when the secondary line is tensioned. The capsule can be manipulated by a user to selectively release the frictional engagement between the primary and secondary lines, thereby enabling controlled transition of the system from a secured state to a state in which the secondary line can translate along the primary line.

An adjustable tethering system is disclosed that includes a primary line, a secondary line, and a bail release feature. The secondary line is wound about the primary line to form a frictional locking arrangement that resists translation of the secondary line along the primary line when tension is applied. The bail release feature is operable to be manipulated by a user to reduce the constriction of the windings about the primary line, thereby enabling controlled transition of the system from a secured state to a state in which the secondary line can translate along the primary line.