Warning —> If you don’t use twitter, this article might give you the extra boost to go ahead start tweeting away..
I met Arwyn’s tweet one day and rest is history! He had posted results from his undergraduate class about how there are essential oils such as lavendar that are actually a more effective bacteriocide than other toxic chemicals such as bleach. Super Rad result! I got in touch with him and, over time, learned about his incredible and very global climate change relevent research on microbes that live on ice and snow of the Arctic.
I sent him a few basic questions and voilà! Enjoy.
1. Tell MO BIO about your project
My principal interests are in the interactions between microbes and glacial systems. This summer is very busy for my team as we are working on projects in Svalbard, the Canadian Arctic, Greenland, the Swedish Arctic and the European Alps. At the moment we are wrapping up our Greenland project, which is funded by the Royal Society in the UK. The project aims to build our understanding of how microbial communities on the surface of the Greenland ice sheet change through space and time. Here I have been working with my co-investigators Dr Tristram Irvine-Fynn, also of Aberystwyth University, and Dr. Joseph Cook of Derby University to collect samples and conduct experiments from a science camp on the ice sheet run by the Dark Snow Project.
2. Why is it important?
Not too long ago scientists assumed that glaciers and ice sheets were too hostile for life to survive on them. We know now that microbial life is abundant, active and diverse in form upon, within and beneath glaciers and ice sheets. The microbial population of glacial systems is vast and poorly explored, but microbes play key roles in how glaciers and ice sheets work (DOI: 10.1002/wat2.1029). We recently published some papers on the abundance of microbes at the ice surface (e.g. DOI: 10.1002/cyto.a.22411). To put the numbers into context – well, the media seem to measure glacial disaster in SI units of “Manhattans”. I calculated that an iceberg the size of Manhattan would harbour an equivalent number of microbes in its top few metres of ice as the number of cells in the human population of Manhattan. Just a decade or so ago we had little idea these were habitats for life.
The flipside of this is that glacier melting becomes an ecological problem and not “just” a case of rising sea levels. Microbial habitats on the ice surface are both vulnerable to climate change and amplify its effects. Microbial biofilms and aggregates at the glacier surface, for example cryoconite and ice or snow algae, darken the ice, reducing its albedo and promote melt. In the bluntest of terms the microbes represent a powerful biological feedback to melting at the surface of glaciers and the Greenland ice sheet. We can see “dark zones” of low albedo and intense melting from satellite observations. When you ground-truth these areas you find that these areas are rich in cryoconite ecosystems, and that the “darkness” is derived from humic compounds made by microbes in the cryoconite.
3. What are some potential outcomes?
I hope our project will help map how these microbial communities change over space and time, in particular in relation to melting seasons. Although as I mentioned earlier, we are focused on how microbes cause melting, microbes also respond to melting, and that’s an important facet of our work. Back in 2012, 97% of the surface area of the Greenland ice sheet experienced surface melting, if only for a few days or a week at its extreme limits. On the basis of work on Svalbard glaciers, I hypothesized (doi:10.1038/ismej.2013.51) that some bacterial populations could respond to this melting episode, creating a spatially-expansive but very brief microbial bloom across Greenland in response to the availability of liquid water and nutrients. A massive event in nature but because of its invisible microbial nature, two years later we have no idea if it really happened or not. Last Saturday we lucked out and were able to take samples far inland to see if there are any traces of microbial changes in response to previous melt episodes. I can’t wait to get these samples back to my lab in Aberystwyth.
4. How is your science important to the public?
My team is intensely passionate about how microbes interact with the ice surface. What began as an academic pursuit for us has assumed a broader significance because of the feedbacks between biology and ice melting. We know as the climate warms, Earth’s glaciers and ice sheets will contribute to raising sea levels. This will affect humans across the world, be it people living in low-lying coastal areas which will be at risk of inundation, the hundreds of millions of people that depend on water from sources replenished by glacial melting, or the rest of us that consume food from crops grown in these areas. There is a growing body of evidence that microbial processes considerably accelerate the melting of ice surfaces, so our work plays a small but important part in understanding how ice melt will change our lives.
I’ve been using MO BIO kits for extracting nucleic acid from environmental matrices for over a decade. I must have extracted thousands of samples. In all that time I have only had six or seven samples fail to yield usable DNA! Soils of all kinds, sediments, biofilms, river water, ice melt, snow, air samples. Even cryoconite, which is particularly challenging as while its biomass is relatively low, it is enriched in humic substances that inhibit PCR. MO BIO kits have made environmental genomics much more accessible.
Secondly, we have increasingly been facing a challenge I refer to as the “rime of the modern glacier biologist” – ice, ice everywhere, and not a lump to freeze! We work in remote environments, far from the nearest ultrafreezer, and liquid nitrogen or dry ice are impractical to use in deep field. Nevertheless, high quality nucleic acids that are representative of the microbial community at the time of sampling are important to us. Stabilizing solutions such as Soil Lifeguard help a lot.