Our research is part of a large comparative sampling effort, in cooperation with other universities and institutions that aims to unravel the complex interplay between light absorbing impurities (LAI; e.g., microbes, mineral dust, black/brown carbon, etc.), and glacial ecosystems. In particular, we are interested in how LAI affect glacial melt rates (their impact on albedo), and their fate following melt events. We then hope to use these data to contribute to larger global melt models that attempt to predict climate change in the future.
The biodiversity of these glacial ecosystems will be explored using a variety of ‘omic’ techniques. These include targeted amplicon sequencing of ribosomal genes, metagenomic and metagenomic sequencing to infer microbial physiology, and mass spectrometry of metabolites in order to determine downstream metabolic processes. We are particularly interested in the role that snow and ice algae play in glacial ecosystem processes. Previous research has shown that algae can reduce albedo by up to 13%, which can dramatically increase melting. We’ve also documented that when melting starts, snow and later ice algae are the main primary photosynthetic organisms that bloom on glacier surfaces.
Additionally, we are interested in the geochemistry of these environments as it is very important in determining the types of organisms that are able to survive and thrive. Assessing the geochemistry can provide a picture of nutrients available on glacial surfaces which may be bioavailable for growth processes. Analysis of the geochemistry of the system is accomplished by evaluating cations and anions in snow, ice, and meltwaters.
Furthermore, algal blooms can produce large amounts of organic matter, however we understand little about the processes that control the production of organic compounds nor how and if they are further degraded by heterotrophic organisms or become exported through rivers to fuel ocean productivity. Assessing the carbon inputs to the system (anthropogenic or otherwise) can also help us to determine the carbon sources available to drive biological processes. Analyses are performed on glacial samples in order to determine dissolved and particulate organic matter composition. This data provides us with a comprehensive view of all organic and inorganic inputs through air and by snow to the surface of these glacial ecosystems.
Such combined microbial diversity and organic carbon data are crucial if we want to understand and quantify the fundamental processes leading to glacier melting and derive data sets that will be implemented in global numerical climate models.
Current research projects under this research theme include: