Last report of IPCC clearly stated that nowhere is climate change more visible than in the polar regions, making them the most critical reference regions for the detection and understanding of global change and its effects on biodiversity and ecosystem functioning. The polar biome is a highly connected ecosystem with linkages all over its components and beyond. However, can we consider the Antarctic region an early warning site?

 

All life on Earth is linked to microorganisms by being absolutely basal to the conversion of organic matter and energy that underlie the biosphere. On one hand, the balance between carbon sequestration and release depends on the ecological makeup of the microorganisms constructing an ecosystem as microbes have specialized traits to use distinct pools of organic carbon. On the other hand, the chemical diversity of the organic compounds present in the different biomes in the form of dissolved organic matter (DOM), can be crucial allowing an organic compound to serve as microbial food source or becoming recalcitrant and accumulate in the ocean for millennia. With atmospheric CO2 concentrations and global temperature rising in the next few decades, the ocean will become warmer, less oxygenated and more stratified. The lack of knowledge about environmental drivers behind microorganisms and DOM pool functioning in response to these changes, especially in Polar Regions limits our capacity to understand and predict the consequences of human activities and its associated global effects.

 

Our overarching hypothesis is that the environmental changes regarding precipitation and moisture regimes imposed by global climatic trends directly affect the microbial activity of polar terrestrial-marine microbiomes and hence local and regional ecosystem functions. Here our objectives are to (a) study the Antarctic microbial assemblages’ responses to the proposed temperature scenarios for 2050 by the IPCC; and (b) investigate the interplay between microbes and DOM at the land-to-ocean continuum of the Northern tip of the Antarctic Peninsula.

 

The NEIGE project field and experimental work in Antarctica was performed in December 2023 onboard the RV National Geographic Explorer by Dr. Gonzalo Gomez-Saez and the other Co-PI of the project Dr. David Velázquez (UAM, Madrid, Spain). Both researchers were "Visiting Scientists" with funds from Lindblad Expeditions and National Geographic (LEX-NG).