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INSTAAR has announced its Summer Scholars for 2024: Natalie Aranda and Jed Lenetsky. The scholars will each be awarded a stipend for the summer months to continue their research projects.

These diversity, equity, and inclusion (DEI) scholarships are designed to increase support for students from communities that are historically marginalized in the Earth sciences, and to be concrete commitments toward INSTAAR’s mission of becoming an inclusive and anti-racist institute.

Natalie and Jed shared some key themes of their research and summer plans.

Natalie Aranda (CEAE) is evaluating the role of tardigrades as grazers in ephemeral Antarctic streams

What will you be working on this summer?

 

My research is looking into the trophic interactions between diatoms, which are siliceous based brown algae, and tardigrades. In the McMurdo Dry Valleys of Antarctica, where my research focus is, there are ephemeral streams in which microbial mats grow. We know that diatoms live in these mats. And we know that there are invertebrates such as tardigrades, nematodes, and rotifers all coexisting in these mats. However, much of the research that has come out of the McMurdo LTER has stated that there is no grazing being done to the diatom population.

But there likely at least some grazing going on, because these invertebrates live in the steams. And elsewhere in the world where there are diatoms and tardigrades, we know that they feed on diatoms. But no one’s quite looked at it yet.

I had the very fortunate opportunity to participate in McMurdo LTER for two field seasons. I got to collect the samples that I’m analyzing now.

What will the scholarship enable you to do?

It’s giving me the opportunity to focus strictly on my research, which is so amazing. I was supported on a teaching assistantship this past semester, and it was incredibly hard, between classes and TA responsibilities, to try to find time to do my research. So this summer, I’m excited to just focus on my research. It’s very microscope intensive, so it’s not the type of thing I can do in between classes or in my down time. I have to come into lab.

I’m looking at these slides that I’ve made from the samples I collected in the Dry Valleys, and I’m counting to see how many diatoms are in the slides. I’m also checking to see if they have chloroplasts present, which would indicate if they were alive when they were collected. And if we’re seeing there’s a high proportion of tardigrades in a sample and a high proportion of diatoms that are lacking chloroplasts, then that could be a connection showing that they’re being grazed upon.

I’ve already begun to analyze the relationship between tardigrade abundance and how many cells I find with or without chloroplasts. But I haven’t finished that aspect of my research. And so I want to continue to count those slides.

The research process requires a lot of thinking. When I’ve got the data—let’s see how it connects, how I can visualize it. That takes a lot of time that I didn’t have during the semester.

What do you like to do when you’re not sciencing?

I feel like there’s two sides of me. One side likes to get out. I’m originally from California, so this is my third year in ÃÛÌÇÖ±²¥. There’s a lot of ÃÛÌÇÖ±²¥ I haven’t seen. I love to go explore different nature spots; I like hiking and exploring.

The other side of me likes to stay home. I love to paint—I’ve been an avid painter my whole life. I work on big pieces, usually commissions that my friends and family have given me. I make landscape paintings or cityscape paintings. That’s my creative outlet.

Jed Lenetsky (ATOC) is forecasting the future of Baffin Bay and its ecosystems in a changing climate

What will you be working on this summer?

 

This summer I’m focused on finishing up two different projects, both related to how the ocean in Baffin Bay is changing. Baffin is a critical region between the Canadian Arctic Archipelago and western Greenland, and it’s a region where you have lots of interactions between waters leaving the Arctic Ocean and entering the north Atlantic, and waters from the north Atlantic entering Baffin Bay. All these waters have very different properties.

One of these projects is looking at is a specific region in the northern tip of Baffin Bay called the North Water Polynya, which has one of the most productive ecosystems in the Arctic Ocean. We’re looking at climate models to understand how the North Water Polynya is going to change under different levels of global warming. We’re basically using a few different climate model simulations developed at NCAR that limit warming in a few different scenarios: 1.5 degrees, 2 degrees, and a business-as-usual scenario of warming over 3.5 degrees Celsius. This is different from a lot of climate models that have      temperatures increasing with time. What this allows us to do is understand the impacts to this region at very specific warming levels that are policy relevant. One of the things that we found is that if we limit warming to under 2 degrees Celsius, we can really avoid large negative impacts to the ecosystem in the North Water Polynya. But we begin to see really large negative impacts to the ecosystem if warming goes above 2 degrees.

The second project I’m working on—there’s an array of ocean instruments in the southern end of Baffin Bay, in the Davis Strait. You basically have a string of measurements going across that strait that tell us how much salt, how much heat, and how much water from these different regions are coming in and out of Baffin Bay. Currently, the published record of these ocean transport only goes from 2004 to 2010. I’m working to extend that record from 2004 to 2022. It’s going to significantly increase our understanding of how ocean waters are exchanged between the Atlantic and Arctic Oceans.

We know from our North Water Polynya paper that the amount of water from the North Atlantic coming into Baffin Bay plays a really large role in ecosystem productivity and how that’s going to change under different levels of global warming. So understanding how those ocean transports are changing now, over this record, is really important.

What will the scholarship enable you to do?

The North Water Polynya project came out of a grant on which Alex [Jahn], my advisor, was a co-PI on the grant and Anne Jennings was the lead PI, looking at past/present/future changes in the North Water Polynya. The paper came out of that work, but that grant has since expired.

So what this scholarship is allowing me to do is basically publish this work.

What do you like to do when you’re not sciencing?

Right now I’m really into getting my garden sorted out, now that it’s finally safe to plant things outside—I feel like the risk of snow is lower now.

I also really like cycling and hiking and running and trail running—basically all kinds of outdoor things.