KECK INSTITUTE FOR SPACE STUDIES

       



KISS Brings Diverse Perspectives to the Table

Andrew Thompson, Professor of Environmental Science and Engineering at Caltech, uses fleets of underwater robots to understand how ocean eddies transport heat and affect the climate. “The ocean has weather just like the atmosphere does. We don’t think about it as much, how the ocean changes from day to day, but ocean weather has a big impact on where heat is carried around in the ocean.” With surface temperatures rising worldwide, Earth’s oceans are pulling double duty: absorbing much of that excess heat as well as taking up carbon directly from the atmosphere and storing it at depth. “That’s a really great thing at the moment, but it won’t do that indefinitely. What we really hope to understand is how the ocean is storing that carbon and heat at depth, and all of that depends very sensitively on the surface properties of the ocean and the structure of those properties.” Ocean eddies may be responsible for much of this circulation, but these underwater weather patterns remain relatively mysterious. “We’re really trying to predict how the exchange of carbon between the atmosphere and the ocean will change through time.”

In 2013-2014, the Keck Institute for Space Studies (KISS) conducted a study to investigate the premise that autonomous and coordinated groups of ocean robots, working in cooperation with remote sensing and shore-based data assimilation, could significantly advance our ability to obtain ocean observations needed to constrain the marine carbon cycle. The primary conclusion of this meeting was the need to develop techniques that allow heterogeneous groups of robots to autonomously determine sampling strategies with the help of numerical ocean forecasts and remotely-sensed observations.

A central concept that emerged from the study was the use of fleets of mobile heterogeneous platforms working in a coordinated manner to obtain observations over a broad range of temporal and spatial scales. The heterogeneous robots, which could include autonomous surface vehicles (ASVs), autonomous underwater vehicles (AUVs), Long-Range AUVs (LRAUV), and ocean gliders, communicate with each other via wireless communications and with data assimilation efforts on shore.

To do that, Thompson’s team needs to collect measurements far below the waves, which is no small feat. “We’re looking not just at the surface, but how that heat is distributed throughout the ocean, and this has traditionally been a very difficult thing to do. Satellites help a lot for the surface, but seeing into the interior of the ocean is a real challenge.” That’s where underwater autonomous vehicles, or UAVs, come in. “Ocean robotics is a new tool that the community has been using to try and really explore the different regions of the ocean and be out there for long periods of time to capture the changes that are happening.” With a fleet of these miniature submarines, Thompson’s group can receive data from remote places without lengthy and expensive crewed expeditions. “They’re sending those observations and data back in real time via satellites, and that allows us not only to really be involved with what those instruments are seeing, but we can make choices about where to send them in real time.”


What’s unique about KISS is they really try to bring in people that think about problems in different ways.

This approach has proven especially helpful in understanding ocean-ice sheet dynamics in Antarctica, the focus of a 2013 KISS study co-led by Thompson. “A lot of the changes we’re seeing are mostly in polar regions, and those have really been places where we’ve struggled to collect observations and make measurements because it’s a remote and harsh environment. Starting to think about how you bring robotics to bear on the climate problem, the polar regions are actually almost the perfect place where these robotics can be most efficient.” Because these regions have pockets of warmer water deep below the surface, autonomous vehicles can provide a wealth of information that would otherwise be missed by remote sensing techniques alone. “That’s why the robotic techniques have been so important for observing these changes around Antarctica.”

During the KISS technical development program, two intensive field programs were carried out in 2016 and 2017. The field program consisted of multiple experiments with a heterogeneous fleet of assets. These experiments consisted of testing front detection and tracking technique developed utilizing multiple vehicles to delineate and track a dynamic ocean front. The first experiment utilized the Tethys-Class Long Range Autonomous Underwater Vehicles (LRAUV), developed and operated by MBARI. The second experiment consisted of two Iver AUVs, owned and operated by WHOI. The third and final experiment consisted of a single Seaglider, provided by Caltech.


Ocean Exploration at Home and Abroad

A second KISS study followed up on the first, providing an opportunity to hone these robotic techniques with input from a variety of perspectives. “What’s unique about KISS is they really try to bring in people that think about problems in different ways,” Thompson says. “It was actually bringing a lot of engineers to the problem, people that have thought about how you put robots under ice, even if they weren’t asking the same questions about how the ice shelves are melting. And that was really eye opening because a lot of things that the oceanographic community thought you just couldn’t do, the engineers were able to say, “Well, we’ve thought about that before. Actually we can do that.” And that’s been very exciting in terms of thinking about what we do going forward.”




Underwater Weather Forecasts

With a little help from KISS, Thompson’s earthbound explorations are reaching beyond our pale blue dot to help us understand ocean worlds, like Jupiter’s icy moon Europa. “When we developed the first KISS workshop, the questions were at least initially focused on the Antarctic ice shelves, but — again, one of the exciting things about bringing different people to the problem — it became very clear quickly that there were analogs here for how you might actually go out and do planetary exploration, specifically on icy moons, what we sometimes call ocean worlds in our solar system.” Collaborators brought together during the KISS studies have submitted a proposal to JPL’s Peace Star Call to develop technology for navigation under ice sheets, to be tested in Antarctica with an eye toward future exploration of Europa. “It’s very exciting to think about the ocean as one of the last unexplored places on Earth. So if you think about how you might build programs to go and explore elsewhere in our solar system, thinking about exploring other planetary bodies, it seems that the easiest way to do that is to get out there into the ocean and start thinking about what are the different ways that you can actually explore and measure different properties.”


What has been very exciting and what’s changed after some of the KISS workshops I’ve carried out is the ability, for me and certainly our group as well, to think bigger about the science that we could do with these robotic platforms. It really opens up a lot of possibilities.

Andrew Thompson

Making waves on Earth and beyond, Thompson sees a bright future ahead. “What has been very exciting and what’s changed after some of the KISS workshops I’ve carried out is the ability, for me and certainly our group as well, to think bigger about the science that we could do with these robotic platforms. It really opens up a lot of possibilities.”