Written By: Dyllan Furness, Science Communication Manager | The Florida Flood Hub
In the early 1980s, Frank Müller-Karger arrived as a graduate student at the University of Alaska’s Institute of Marine Science in Fairbanks. His goals were simple; he wanted to study whales and see faraway places. But fresh out of undergrad and more than 5,000 miles from his hometown in Venezuela, reality soon set in for the aspiring marine biologist.
“There just wasn’t enough support or funding for that kind of whale research,” says Müller-Karger, who was recently honored as a Distinguished University Professor at the USF College of Marine Science.
So, he followed the funding. Under the tutelage of his trailblazing advisor and marine scientist, Vera Alexander, Müller-Karger shifted his research interest from the ocean’s largest inhabitants to some of its smallest — from whales to phytoplankton. He climbed aboard research ships and airplanes bound for the Bering and Chukchi Seas, where he studied phytoplankton blooms that stretched to the horizon along the edge of the Arctic ice pack. The goal of these expeditions was to study the ice edge as the seasonal ice pack grows in winter and retreats to high latitudes in summer. The ice edge is a place teeming with life.
Frank Müller-Karger’s captivating career path went from a budding interest in whale research to pioneering work in studying phytoplankton blooms via satellite technology.
“My master’s program allowed me to really experience what it was like to be a scientist,” Müller-Karger says. “Those were my first opportunities to go out on real research expeditions. I learned I could have a career doing these great activities, having adventures, and having fun.”
It wasn’t just for fun. During his graduate program, Müller-Karger honed his skills as a scientist and deepened his understanding of ocean processes. He learned how light, nutrients, and marine life interact. His master’s thesis shed new light on the ice-edge blooms of phytoplankton in the Bering Sea.
Throughout his career, Müller-Karger has seized opportunities and adopted new technologies in his pursuit of knowledge. His work has uncovered links between rivers and oceans, advanced the field of satellite remote sensing, and helped promote biodiversity around the world. His recent recognition as a Distinguished University Professor highlights Müller-Karger as outstanding among his peers.
Studying the ocean from space
Soon after earning his master’s in oceanography in the mid-1980s, Müller-Karger found himself in a room at NASA’s Goddard Space Flight Center sorting through hundreds of thousands of paper photos and negatives of satellite images. He was a PhD student at the University of Maryland researching phytoplankton productivity in the Amazon River.
At the time, there was no easy way to browse through the satellite images stored on 10.5-inch reels of magnetic tape in massive paper and tape archives. Although the images were often cloudy and tough to discern, Müller-Karger became so proficient at identifying landmarks and features, and in processing the digital data from the tape reels, that NASA offered him a fellowship.
The USF Distinguished University Professor title recognizes Frank Müller-Karger for his dedication to the conservation of the ocean and for his impact as a researcher, professor, colleague, and mentor.
It was around that time that he made a discovery. While comparing patterns in the color of the ocean from satellite images of the Gulf of Mexico, Atlantic Ocean, and Caribbean Sea, Müller-Karger identified never-before-seen plumes of cloudy water from some of South America’s mightiest rivers.
“It was spectacular,” he says.
Rains, winds, and ocean currents combine each year to send water from the Amazon and Orinoco Rivers far beyond their river mouths. Venezuela’s Orinoco River paints a trail of turbid water through the blue-green Caribbean Sea, stretching northward from South America to the U.S. Virgin Islands and Puerto Rico every September-October.
Water from the Amazon River meanwhile reaches eastward across the deep-blue Atlantic, nearly as far as Africa, during some months the second half of the year.
“These are two of the largest rivers in the world and no one had seen where their water goes,” he says. “People in the Virgin Islands and Puerto Rico knew their ocean water became turbid once a year, but they didn’t know why. This is why — discharge from the Orinoco, which is six hundred miles away.”
Turbid water contains particles such as sediments originating from rivers. But in the hazy plumes Müller-Karger observed via satellite, it was the phytoplankton that most intrigued him.
“The phytoplankton in the water made me more interested in the biological component of oceanography,” he says. “Even though I had a degree in biology, I wasn’t really applying it at the time. I was just looking at ocean color. The connection between ocean color and phytoplankton pushed me to understand more about the connection between these plumes and marine life.”
Preserving biodiversity
Müller-Karger joined USF in 1988 as a research associate in what was then the Department of Marine Science. He held various positions within and outside USF, including at the NASA headquarters as program scientist for ocean biology and biogeochemistry. He became a full professor at USF CMS in 2000 and served as the dean of the School for Marine Science and Technology at University of Massachusetts, Dartmouth. He came back to USF in 2009 to focus on research, which is his true passion. All this time, Müller-Karger has remained committed to studying and conserving marine life.
“We use life as the justification for almost everything we do in marine science,” he says. “Much of oceanography is about understanding changes in life and life’s adaptations to environmental conditions such as climate change. We know that all these changes affect life, and that includes us.”
Recently, Müller-Karger has been focused on promoting best practices for the collection and dissemination of biological data. He was instrumental in the creation of the Marine Biodiversity Observation Network (MBON), an international collaborative initiative that aims to foster effective management of marine biodiversity and ecosystem services, and Marine Life 2030, a program endorsed by the United Nations as part of the Decade of Ocean Science for Sustainable Development. MBON and Marine Life 2030 aim to make biological data readily available to citizens and scientists alike to guide decisions in an evolving economy that depends on the ocean.
“Marine Life 2030 envisions a world where anyone can tap into information about their local marine fisheries and ecosystems,” describes Smithsonian Magazine in an article about the program. “A world where predicting sea life trends is as simple as pulling up a weather forecast.”
To achieve this vision, participants in the Marine Life 2030 team aim to assemble a DNA library of the world’s marine species and connect the many databases that currently exist for cataloging life. Other expert teams involved in Marine Life 2030 bring their knowledge of the use of satellite data, underwater acoustics, underwater optics, and how this all supports resource management and jobs. That will entail leveraging emerging technologies such as artificial intelligence and international collaborations between scientists and local stakeholders.
Though no small feat, interdisciplinary efforts like this are what motivates Müller-Karger and he hopes others join him in that motivation.
The USF Distinguished University Professor title recognizes Müller-Karger for his unwavering commitment to the conservation of the ocean and for his impact as a researcher, professor, colleague, mentor, and someone who is dedicated to service in his community. Among his other recognitions, Müller-Karger was named as a 2018 Fellow at the American Association for the Advancement of Science (AAAS), received the 2021 William T. Pecora Award, and was named a 2024 Fellow at The Oceanography Society.
These honors come as bonuses, he says, to an already rewarding career. “Slowly bumping here and there, I moved along in my career by finding interesting ideas to build projects around, and to take part in. I’ve been lucky to do a lot of what I’ve wanted to do.”
TESTIMONIALS
Dr. Müller-Karger is, by all accounts, an extraordinary scientist. His research accomplishments have been well-chronicled and will undoubtedly have long-lasting scientific and societal impact. Frank is the consummate team builder and has led major, interdisciplinary projects all around the globe. He is not only a valued colleague and collaborator, but an exceptional mentor as evidenced by the many accomplishments of his graduate students and post-docs. His love for the ocean is infectious as is his passion for science and its application.
- Tom Frazer, Professor and Dean, USF CMS
Frank has a broad vision as a scientist, bringing people together and building networks. As a lab manager, he observes situations from all angles to see the best way to move things forward and takes care of everyone involved. As a mentor, Frank brings out a person's strengths and gets them into “the game.” Ever since I met Frank, I feel that I have been expanding my professional view and pushing my limits in positive ways.
- Ana Carolina Peralta, postdoctoral scholar, USF CMS
Starting in his graduate student days, Frank has always been an intense, focused, and prolific researcher producing significant discoveries and manuscripts, in particular about the important waters of our continental margins. He is also a humanist who has spent many years training diverse students and working in other ways to improve ethnic and international diversity in our field.
- James Yoder, Woods Hole Oceanographic Institution Dean Emeritus and University of Rhode Island Professor Emeritus
It is fair to say that some appointees to federal boards — in this case the U.S. Commission on Ocean Policy on which we both served as Commissioners — take the bows, attend the meetings, and sign the final report. Not Frank. He dove in, all the way. He did the research on every issue. He fully engaged in the public hearings and Commission-only debates; a terrific public image for USF. I have stayed in touch with my oceanography and ocean policy career roots and know Frank has continued to make his mark; “all in, all the time” on whatever project he grabs.
- Vice Admiral Paul G. Gaffney, U.S. Navy (Ret.)