World Oceans Day: Thought Leaders

UM Rosenstiel School faculty provide their insight on the oceans.

Dennis Hansell, Chair and Professor, Department of Ocean Sciences

Dennis Hansell“Think of the ocean as you would the blood coursing through our bodies.  It offers connectivity to all corners, leaving no part in isolation.  It carries life-supporting oxygen, nutrients and energy to its greatest and darkest depths.  It exchanges that oxygen and greenhouse gases such as carbon dioxide with the atmosphere above it, keeping both the terrestrial and marine biospheres healthy and stable.  It moves heat from where it is in excess to those much colder zones, maintaining the narrow thermal stability required for life that would otherwise be diminished.  Just as understanding the physical, chemical and biological dynamics of a healthy circulatory system within our bodies is central to medical science, ocean scientists seek to understand those dimensions of the global oceans’ metabolism.  As with the living body, it is a wondrous and beautiful system, its core functions are often hidden and thus incompletely known, and its health is conditioned by our treatment of it.”

 

Benjamin Kirtman, Professor, Department of Atmospheric Sciences

Ben Kirtman“The health of our planet and all of its ecosystems (humans, animals, fish, plants …) critically depend on what is happening in the ocean today. Indeed, current threats to food and water security and the associate famine and drought can be directly related to ocean processes. We are concerned about the health of the planet because ocean temperatures (in the upper 75 m) consistently have risen 1.5F since 1950 and sea-ice concentrations have decreased at record rates so that it is now expected that we will have a nearly ice free Arctic summer in ten years. 95% of all ice sheets are declining and global sea level has risen over half a foot since 1950. All of these unprecedented changes indicate that the climate system and the entire health of the planet is out of balance, and this comes with changes that will significantly challenge all of our ecosystems.”

 

Claire Paris, Associate Professor, Department of Ocean Sciences

Claire Paris“Most marine species, whether they are reef building corals or bluefin tuna, spend the early stages of their life as tiny plankton, navigating the world oceans. To know where they are, where they need to swim, and to avoid predation, these minute larvae are adapted to detect ocean signals, such as sounds, odor, or even celestial and magnetic cues. One of the last frontiers resides in the study of the mysterious world of larvae and the small-scale physical-biological interactions. It is important to understand how the “critical” pelagic phase of so many marine species endure such a challenging odyssey. The ocean is their nursery.  If we care for our oceans to reduce the pollution that affects the cues, we will protect the small things and everything else will thrive.”

Neil Hammerschlag, Research Assistant Professor, Department of Marine Ecosystems and Society

Neil“Over the past 50 years, we have learned more about our oceans, estuaries, rivers and lakes than ever before, while at the same time degrading, overfishing and destroying these vital systems. Every year, over 1.5 billion hooks are set in the ocean to commercially target large pelagic predators including tunas and billfish, catching and killing them faster than they can reproduce resulting in drastic worldwide declines of many species. With changes in global climate, the chemistry of our oceans is changing and corals are bleaching. Not only is the mystery and beauty of these systems and species being lost, but also their functions within the ecosystem. The web of life that sustains us is deteriorating. To aid in understanding and addressing these issues, we are conducting a variety of innovative research projects in collaboration with various University and community partners.”