Their day at sea was part of the school\u2019s Keymester program, an experiential learning initiative in which students not only put their noses to the grindstone in the classroom but also conduct research in the field\u2014in this case, at sea.<\/p>\n
![\"Keymester\"](\"https:\/\/www.newsbeep.com\/us-fl\/wp-content\/uploads\/2026\/07\/keymester-embed2-940x529.webp\")
\nResearchers deploy the sled containing multiple ocean sensors.<\/p>\n
\u201cThe ocean is fundamental to life on Earth. It regulates the climate, drives weather systems, sustains fisheries, and supports the global economy,\u201d said Kim Popendorf, a chemical oceanographer, associate professor in the Rosenstiel School\u2019s Department of Ocean Sciences<\/a>, and Keymester instructor. \u201cBut to understand and learn more about the ocean, we need to continuously study and monitor it. And that all starts with gathering data, collecting the hard numbers that give us a true look at how it is functioning.\u201d\u00a0<\/p>\n Keymester, Popendorf said, provides students a hands-on, academic portal to study the ocean\u2014and it all starts with data.\u00a0<\/p>\n While students regularly meet in labs and in the classroom, the one-day ocean expedition to the Gulf Stream\u2014the swift, warm ocean current that originates in the Gulf of Mexico, flows through the Straits of Florida, and travels northward along the eastern coast of the United States\u2014is Keymester\u2019s signature feature.\u00a0<\/p>\n Heading out to sea\u00a0<\/p>\n On the morning of the last cruise, taken in the spring, the sun had barely breached the horizon on Virginia Key when students from two of Keymester\u2019s core classes\u2014Microbial Geochemistry and Observing Ocean\u2014departed the Rosenstiel School docks aboard the research vessel F.G. Walton Smith.\u00a0<\/p>\n Once the vessel reached the Gulf Stream, where the current is closest to Florida, the research started in earnest, with students deploying from the stern of the catamaran a platform teeming with \u201csensors that measure any kind of data you can imagine,\u201d said Mariana Bif, an assistant professor and marine biogeochemist in the Department of Ocean Sciences, who leads the Observing the Ocean class and has developed many types of sensors from scratch.\u00a0<\/p>\n \u201cStudents have so much data available to them when they work in the classroom, but the data is already quality-controlled from websites and prepared by groups from other institutions,\u201d Bif said. \u201cObserving the Ocean teaches students how to manipulate data in the computer, and by going on this cruise, it teaches them how to collect data but also shows them what that raw data looks like once it gets out of the sensors, which is not going to be as beautiful as the data that they download from the internet.\u201d\u00a0<\/p>\n During the data-collecting process, a hydroacoustic instrument used sound waves to measure the speed and direction of water currents. A bio-optical sensor took readings of oceanic pigments, which allowed students to measure levels of phytoplankton in the water.<\/p>\n Designed and built at the Rosenstiel School, the platform deployed from the stern of the F.G. Walton Smith also contained a plankton imaging camera, an oxygen sensor, and a CTD (Conductivity, Temperature, and Depth) device consisting of small probes that allowed the young researchers to chart the distribution and variation of water temperature, salinity, and density to understand how Gulf Stream waters affect marine life.\u00a0<\/p>\n \u201cI also integrated professor Bif\u2019s nitrate sensor so that students could collect real-time nitrate data during the cruise,\u201d said Cedric Guigand, a Rosenstiel School technologist and engineer who was onboard for the cruise. \u201cThe goal was to help students learn how ocean conditions like temperature, salinity, and biology can change as you move through a front\u2014in this case, the edge of the Florida Current.\u201d<\/p>\n As part of Keymester, Guigand co-taught the class Coastal Oceanography with professor of ocean sciences Maria Josefina Olascoaga, in which students conducted marine and atmospheric research using instruments they designed and built in the Rosenstiel School Makers Lab<\/a> he directs.\u00a0<\/p>\n Data analysis\u00a0<\/p>\n Inside the F.G. Walton Smith\u2019s lab, students conducted preliminary analysis of the data in real time. But an extensive review of the information wouldn\u2019t begin until the students returned to laboratories at the Rosenstiel School, where they employed the data to answer questions related to their research\u2014in the case of Popendorf\u2019s Microbial Geochemistry class, how microbes and nutrients interact.<\/p>\n The data will be used to study a plethora of other oceanographic topics as well. \u201cThe data has so many applications because of the area where we sampled,\u201d Popendorf said. \u201cFrom a global perspective, the Gulf Stream is extremely important, as it\u2019s an essential component in a vast system of Atlantic currents that may be slowing down.\u201d\u00a0<\/p>\n Popendorf is referring to the Atlantic Meridional Overturning Circulation, or AMOC, a massive system of ocean currents that acts as a global conveyor belt, carrying warm water from the tropics northward to Europe. As it cools, the water becomes dense and sinks, distributing heat and regulating Earth\u2019s climate.\u00a0<\/p>\n A growing body of research suggests the AMOC is at risk of collapsing, \u201cand that would have huge climate consequences,\u201d Popendorf said. \u201cIt\u2019s not that the data our students collected can answer that question by itself, but just having the temperature, salinity, and nutrient data they collected from the Gulf Stream can be added to the scientific inquiry being done on the AMOC.\u201d\u00a0<\/p>\n She hopes the data collected from all Keymester cruises will become part of a repository housed at the Rosenstiel School library.\u00a0<\/p>\n Keymester will expand next spring, when Paquita Zuidema<\/a>\u2019s Atmospheric Observations and Instrumentation class is incorporated into the curriculum, giving meteorology students the chance to learn about the ocean from the experts who know most about it: oceanographers.\u00a0<\/p>\n During the next Keymester expedition to the Gulf Stream, \u201cour students will forecast the weather conditions prior to the cruise\u2014in particular, wind speed and direction. And they\u2019ll evaluate their forecasts using observations made during the cruise,\u201d said Zuidema, professor and chair of the Department of Atmospheric Sciences<\/a>.\u00a0<\/p>\n She and her graduate assistant, Ph.D. student Michael Perez, sailed on the last Keymester cruise, launching radiosondes attached to helium-filled balloons that recorded relative humidity, air temperature, and wind speeds. Zuidema\u2019s students will take on the responsibility of deploying the radiosondes during the next cruise.\u00a0<\/p>\n For Hannah Heath, who earned an undergraduate degree in marine science and geological sciences and sailed on the last Keymester cruise as a student in the Observing the Ocean class, the expedition has inspired her to learn new ways to monitor the health of the oceans.\u00a0<\/p>\n![\"Keymester\"](\"https:\/\/www.newsbeep.com\/us-fl\/wp-content\/uploads\/2026\/07\/keymester-embed3-940x529.webp\")
\nUndergraduate Mia White collects water samples from Niskin bottles for later chemical analysis.<\/p>\n![\"Keymester\"](\"https:\/\/www.newsbeep.com\/us-fl\/wp-content\/uploads\/2026\/07\/keymester-embed1-940x529.webp\")
\nAssociate professor Kim Popendorf and students evaluate live data in the lab as it comes in from sensors measuring\u00a0temperature, salinity, oxygen, and phytoplankton chlorophyll.<\/p>\n![\"Keymester\"](\"https:\/\/www.newsbeep.com\/us-fl\/wp-content\/uploads\/2026\/07\/keymester-embed4-940x529.webp\")
\nStudents make final preparations to a CTD (Conductivity, Temperature, and Depth) device before it is deployed in the ocean.<\/p>\n