Icy ecosystems (e.g. glacier, snow, sea ice, frozen lakes) remain the least explored sector of the cold biosphere, yet are now known to be inhabited by significant populations of microorganisms. They are the closest models we have for habitats on other planets and may have been refuges for life during periods of extreme cold in Earth's history. Because of the extreme environmental conditions present (cold, desiccation, high radiation, high pressure and physical abrasion by meltwater/ice) few sensors are developed for these environments and most investigations to date have involved hand-sampling and laboratory analysis of samples. These rudimentary sampling methods yield only limited information and are inappropriate for investigating the more remote deep sub-surface environments, such as lakes beneath the Antarctic Ice Sheet. Significant innovation in the field of chemical/biosensor development is essential for controls on microbial activity in icy environments to be understood, and in order to engage fully in the future exploration of Antarctic subglacial lakes and sub-ice water bodies on other planets (e.g. Mars, Jovian moons). The Principle Investigator has extensive experience in sensor deployment and biogeochemical monitoring in extreme cold environments, including the glacial field site, and will organize and lead a core team of experts to develop the first generation of chemical/biosensors for high resolution monitoring of icy ecosystems. The sensor testing site is a glacier, Engabreen (Norway), where environmental stresses common to a range of icy ecosystems are present. A unique aspect of this site is the exploitation of the Svartisen subglacial laboratory, where tunnels bored in bedrock beneath the glacier enable relatively straight-forward emplacement of sensors in the high stress subsurface environment. This work will provide a platform for the future development of a larger research group focused on biogeochemical sensing of the cryosphere and the acquisition of further funding from a variety of sources.