We are at the South Pole in Antarctica. We’re about a kilometer-and-a-half from the primary station and the geographical pole, the area where we're at now was just open ice sheet before we arrived in November here, and I’m part of what we call the SPICE Core project, so this is an ice-coring project funded by the National Science Foundation. SPICE Core is our nickname for the South Pole ice core.
The main goal of the SPICE Core is to get a deep ice core from the South Pole – one of the first, actually the first, deep ice core from the South Pole for trace-gas research. That’s actually the main research that I do back at my lab at UC-Irvine. We look at the trace gases that have been trapped in the ice cores from about 40,000 years ago up until present, and we can use these trace gases to understand how the climate has changed. Not just so much how humans have changed it, but how it has changed naturally on its own.
Ice cores are a great way to look into the past, and so you can think of them a little like tree rings in that they give you a record of year after year of the snow that falls in the center of the Antarctic ice sheet, and that snow never melts away. You get this great historical record. One of the ways we can understand how our climate system works better is to look back into the past at these abrupt changes. Our goal is to drill to 1500 meters depth, so we're hoping it will take two field seasons. We've made it down to 700 meters, a little less than halfway. We have next season to make an additional 800 meters to get to our goal.
The cutting of the ice is an extremely slow process in order to get good core quality, which is primarily what we’re after. Right now we’re actually make a new ice core, and this will take about 15 or 20 minutes of actual coring. Our Intermediate Depth Drill is an electro-mechanical drill suspended on an armored-steel cable. It’s deployed up and down the hole via a winch. The drill itself runs with an electric motor, and it basically has cutters at the end of it that will take chunks out of the ice sheet, leaving a core behind, which is then recovered by what we call core dogs in the core head, which will grab the core, hold on to it, and essentially break it off from the ice sheet as we pull back on the drill winch.
The ice here seems quite hard. We’ve actually noticed the cutters on our cutter head getting dull faster. We lose little chips out of the corners of them as well. So we’ve had to experiment a little bit and modify our cutters a bit in order to try to core through this harder ice a little faster and little more easily.
So we’re drilling about 24 to 28 meters of ice per day, and that will get slower as we get deeper, because more time is spent going down the hole to start cutting and then more time is spent coming back up the hole. It’s a long process for the ice to get back home. First, we bring it up and package it up on big Air Force pallets. Those go on a four-prop military plane called a Herc. They get flown to the main base in McMurdo. Unloaded there quickly and put into container freezers that have dual refrigeration units because we need to keep them cold. That container gets loaded onto a vessel at McMurdo and then it gets taken by vessel all the way to California. In California, it gets loaded onto a truck and driven to Denver, Colorado, where the National Ice Core Lab is, and that’s kind of its home until we start making measurements on it, start cutting it up and sending it around to different labs in the U.S. A portion of it remains at the Ice Core Lab well into the future as an archive.
Hitting our goal of 700 meters actually occurred today, this morning. It was a great feeling, because after we’ve had some hurdles along the way, and it’s the first season of a new project, so it takes a lot of get up and go. We work long hours, but at the end it’s exciting because I know this core is going to provide some really awesome science for people like myself and other young, aspiring students and scientists across the world.