When faced with climate extremity, polar expedition members in the long nineteenth century experimented with media forms adequate to representing their position both out of place (at the ends of the earth) and out of time (in sunless polar winters, absent diurnal time). These forms might be called “polar ecomedia,” Blum proposes. She focuses on the ephemeral forms of expeditionary polar ecomedia, which include ship newspapers, notes in bottles, letters and cairn messages, and rescue notices printed on colored silk, all of which polar sailors used to mark time and communicate information. In the polar regions, ephemera are testimonials to (and fuel for) resilience, perhaps counterintuitively. In our contemporary Anthropocenic moment of accelerating Arctic and Antarctic polar ice sheet collapse, human life on earth can itself feel ephemeral, both because of and despite humans’ irreversible impact on global climate and the geological record. The evanescent textual records generated in polar extremity, Blum argues, offer unexpected conceptual and formal devices for describing, comprehending and, most ambitiously, surviving climatic extremity.