The McMurdo Dry Valleys Long Term Ecological Research project has been running for more than 20 years and is a huge operation, with 12 principal investigators (lead scientists) and dozens of collaborators and graduate students from institutions across the Unites States and beyond. As I’m sure you can imagine, it can be hard to keep such a large group of people organized and focused. Just think about trying to do group projects with only 3 or 4 classmates!
One thing that keeps the project focused is the fact that every six years, the team submits a proposal to the National Science Foundation. In order to get money to fund the project, the lead scientists must show that they have a plan for the next six years. And one of the most important aspects of this plan is an overarching guiding question that the scientists hope to answer. This question is what keeps all the lead scientists on track – it’s their group project assignment. Right now, the big question has to do with climate warming: How will climate warming alter the McMurdo Dry Valley ecosystem? Based on more than 20 years of experience, the lead scientists have some ideas about what will happen. But rather than just give away their predictions, I want you to make your own. In order to do that, you need a little more information about the Dry Valleys.
As I mentioned in an earlier blog, the McMurdo Dry Valleys make up the largest area of ice-free land on the Antarctic continent. But the Dry Valley system isn’t just bare rock. There are numerous mountain glaciers flowing down into the valleys, ending abruptly in tall cliffs of ice. These glaciers are critical components of the Dry Valley system because they provide the majority of the liquid water that flows during the brief Antarctic summer. Streams, which flow for only two months out of the year, carry this glacier melt-water across the bare soils into lakes. As the water runs over rocks and soils, it picks up minerals and nutrients, carrying them into the lakes as well.
Streams, which flow for only two months out of the year, carry this glacier melt-water across the bare soils into lakes. As the water runs over rocks and soils, it picks up minerals and nutrients, carrying them into the lakes as well. During the summer, only the very top layer of soil thaws – dig down less than a foot, and you’ll hit frozen soil, or permafrost. Lakes in the Dry Valleys are unlike any lakes we have in the Northeast – they are always covered in a thick layer of ice, even in the height of summer. Water underneath the ice remains liquid throughout the entire year, but it is separated from the rest of the world by a solid sheet of ice.
Glaciers, streams, soils, and lakes are the physical parts of the Dry Valleys – but there is life found everywhere. Moss and algae can be seen by the naked eye, but hundreds of other organisms, too small for us to see, live in the soils, streams, lakes, and glaciers of the Dry Valleys.
So, with this introduction to the Dry Valleys, think about how the system might change with a warming climate. It might be helpful to consider each component (glaciers, streams, soils, and lakes) separately, but remember that they are all linked. In my next blog, I’ll discuss one of the predictions that the lead scientists have. First though, you have to make your own predictions!