Abstract

The polar regions are home to important and dynamic components of nutrient cycles, from subglacial weathering to biological production and carbon sequestration in marine sediments. The Arctic, parts of the Antarctic, and glaciated mountain ranges (the ‘third pole’) are also some of the most climatically sensitive locations on Earth, where the most dramatic warming and associated physical and chemical changes have been observed in recent decades. If we are to comprehend the implications of anthropogenic climate change for future oceans, we need to examine how such rapid change in the polar regions could be either amplified or mitigated by biogeochemical feedback mechanisms. Here, I will explore the cycling of one key nutrient, silicon (Si), in the subarctic and Chilean Patagonia, using a range of physical, chemical and biological approaches to answer the questions: What are the mechanisms behind Si release in glacier systems? What are the downstream processes influencing the delivery of Si to the oceans? And how do we explore rates of Si flux to the open ocean?