How will glacial meltwater microbes come in from the cold in this "Peak Melt" century?

Global warming is melting many of Earth's glaciers, increasing the production of meltwater as the glaciers expire.

In the worst-case scenario, up to 85% of glaciers will be lost by 2100, which will then mean the production of meltwater will decline drastically. About a billion people depend on rivers fed by glacier meltwater for water, and nutrients in glacial meltwater fertilize crucial ecosystems.

This glacial meltwater contains bacteria and their products. We have found some of these products are made to protect bacteria against their viruses, and have proof that these same products have a second job in dissolving nutrients from rocks. Earlier research tell us the meltwater bacteria, their products and the nutrients are critical for important ecosystems in the land and sea fed by glacier meltwater. But we do not know how many of these three things will be released as the glaciers die, how they will interact and what this change in the supply of bacteria, products and nutrients will mean for ecosystems fed by glaciers that will disintegrate this century.

Our proposal aims to address these three gaps in our knowledge. In this project we will go to valley glaciers on Svalbard in the High Arctic, in Austria in the European Alps, and Livingston Island at the tip of the rapidly warming Antarctic Peninsula to see how microbes and their products are released from glaciers.

At each location we will collect samples from the glacier surface which will tell us how the microbes grow in the ice surface and how they are released. We will conduct experiments to reveal how the "arms race" between microbes and their viruses affects the delivery of microbes, their products and nutrients in the meltwater. We will also sequence the DNA of microbes living in the ice surface and meltwater to see who is living in this very large, but poorly understood and endangered habitat. We will use our fieldwork and lab analyses to inform models of how glaciers release their microbes, and what this means for downstream habitats.

By doing this we will have a clear picture for the first time of how the loss of glaciers will release microbes, and what those organisms may do as they are washed out to important environments downstream of the glaciers.

Our project has fundamental academic, societal and economic benefits linked to understanding life in the cold and how it will respond to contemporary climate change and its impacts on the food and water security of billions of humans living in many thousands of catchments worldwide. End users will benefit in the following ways:

Academia: Our project will deliver a clear advance in academic disciplines linked to cryospheric microbiology and biogeochemistry, for example glaciology, geochemistry and genomics. Delivering the first characterization of life within a habitat new to science but crucial to biogeochemical impacts of glacier loss will provide transformative datasets within this field. We will communicate our work through peer reviewed publications, conference presentations, knowledge exchange with UK and international partners and the training and career development of two PDRAs, thus supporting the UK and international knowledge economy.

Highly skilled individuals: This project supports knowledge exchange in the emerging field of in-field metagenomics by holding a workshop on "Extreme Metagenomics". A key objective of this workshop is to foster a new research community and to up-skill a new generation of microbial scientists by hands-on training in in-field metagenomics. This complements the training/career development of project associated early career researchers, (PDRAs Joseph Cook, Sara Rassner,MicroArctic ESR Melanie Hay).

Economy and Society: This project focuses on an aspect of an existential threat to economy and society, namely climate change impacts. A second serious threat facing contemporary society is the antibiotic resistance crisis. Extreme environments are under-exploited sources of bioactive novelty, and the generation of microbial isolates and datasets from a habitat new to science generates a resource for discovering new antimicrobial drugs. We will exploit this efficiently by our links to the MicroArctic ITN Early Stage Researcher Melanie Hay.

Outreach: Climate change and the cryosphere is a hot topic. We will engage the public through new (social) media streams and our contacts within the broadcast and print media. The project's website will be populated with contemporary genomics data, generating a "news bulletin" of microbial diversity released from glaciers as it is liberated. At one level this data will be useful to the academic community, but by complementing the data with accessible "character" profiles of interesting species we will bring public attention to microbial dimensions of melt for the first time. We will bilingually engage with our regional communities through a series of outreach opportunities afforded by activities such as the Aberystwyth Science Café and the Welsh Urdd Eisteddfod GwyddonLe ("Science Site") exhibition. Our prior experience with GwyddonLe indicates an audience of ca. 25,000 visitors over each 5 day youth festival, thus reaching a broad audience of the public across Wales.