Center for Marine Research

Prof. Assaf Vardi earned a BSc in Biology from the Hebrew University of Jerusalem, from which he also received an MSc in Environmental Sciences and PhD in Molecular Ecology. After conducting postdoctoral research at the École Normale Supérieure in Paris and at Rutgers University, he joined the Weizmann Institute faculty in 2010 where he is the incumbent of the Edith and Nathan Goldenberg Career Development Chair. He was also appointed an Adjunct Scientist at the Woods Hole Oceanographic Institution (US). Prof. Vardi has received several awards, including two Reiger Foundation awards, a Marie Curie fellowship, and a Legacy Heritage Brain Drain fund award from the Israeli Science Foundation. In addition to support from the Gordon and Betty Moore Foundation, Simons Foundation, and Israeli Science Foundation, he has been granted a Human Frontiers Award, and the prestigious ERC young, consolidator and advanced investigator grants from the European Union.

 Prof. Vardi elucidates the molecular mechanisms that drive microbial interactions in the marine environment. Microbial interactions that regulate the fate of algal blooms play a profound role in determining carbon and nutrient cycling in the ocean and feedback to the atmosphere.  Prof. Vardi studies some of the key mortality agents of algal cells such as marine viruses, bacteria, and grazers. The specific interactions between algae and their pathogens will lead to the demise of algal blooms and will have a unique footprint on the environment. Assaf and his team study how each interaction will differentially influence not only the surrounding microbial population, but also the carbon export to the deep ocean, recycling of nutrients available to the rest of the marine organisms, biodiversity, and even how they may influence the atmosphere above the decaying bloom. The latter occurs when dying algal cells produce volatile molecules that are emitted to the atmosphere as aerosols and can modulate cloud formation.

 While most of the basic science is performed in the Vardi lab and allows for interesting discoveries of the biology and chemical ecology of microbial interactions, Assaf and his team are passionate about testing their findings in the real world, in natural populations in the ocean. To measure microbial interactions within algal blooms, they study specific genetic and metabolic biomarkers that are induced during a myriad of interactions. During field campaigns, Prof. Vardi’s research group detect and measure these biomarkers and couple them with bloom dynamics and environmental parameters, to gain a holistic view on the bloom ecosystem.

Prof. Yinon Rudich is a Professor and Dean of the Faculty of Chemistry at the Weizmann Institute of Science. His research focuses on studying aerosol chemistry and physics, and the effects of aerosols on climate and human health. He has established a state-of-the-art aerosol Physics and Biology lab to study the optical properties, ice nucleation, and health effects of aerosols, and he has also created a national pollutants database to study the health effects of exposure to pollutants.

The overarching goal of Dr. Rudich’s research is to provide a mechanistic understanding of the connections between the physical and chemical properties of aerosols to their ability to nucleate ice, absorb and scatter solar radiation, and induce health effects. Dr. Rudich also studies the aerobiome – bacteria, viruses and fungi that are transported in the atmosphere by dust and winds, and their potential impacts on ecosystems and human health.

Dr. Rudich has authored more than 250 peer-reviewed articles and serves as an expert reviewer for the European Commission and ERC. He is a member of the WMO Global Atmosphere Watch Programme’s ARCH (Air Pollution, Climate Change, Health Effects Nexus) working group, is on the scientific advisory board of SPARTAN, and is a member of the international steering committee of the Tropospheric Ozone Assessment Report (TOAR II). He is a Fellow of the American Geophysical Society (AGU), the Royal Society of Chemistry (FRSC), and Academia Europea.

Materials of the Ocean
The group studies mineralization processes in two of the most abundant algal groups of modern oceans, diatoms, which form silicified cell wall with nano-patterning unequaled by any synthetic system, and coccolithophores, which form calcified scales with unprecedented control over crystal orientation and morphology.
 

Geochemistry Clean Lab
The group focuses on discovering past environmental changes and the interaction between land and ocean by analyzing the chemical composition of sediments and water.
 

Environmental Microbiology and Microbial Ecosystems
Dr. Zeevi combines his research with microbes and AI to see if these tiny creatures can increase crop yields and their resistance to droughts and rising temperatures. By sampling many unique wheat-growing plots and sequencing the DNA of all microbes (bacteria, fungi and viruses) in these plots, Dr. Zeevi and his team are using machine learning to pinpoint the ones that have a positive effect on the crop.

The group also studies how microbial ecosystems are affected by human-made artifacts, and it applies the insights learned from these microbes to devise new ways to protect the environment.
 

Cloud Physics
The group explores the physics of clouds and rain as well as ocean-atmosphere interactions and nonlinear dynamics. Its research ranges from theoretical exploration of differential equations through numerical simulations of clouds and cloud fields, satellite data analysis, field measurements, and remote sensing. The group develops and merges approaches from fluid dynamics, complex systems, radiation transfer,  cloud microphysics, computer vision, and statistics.
 

Atmospheric, Oceanic and Climate Dynamics
The weather and climate on Earth are mostly controlled by the large-scale flow in the atmosphere and ocean. Thus, to improve our preparedness for future human-induced climate change it is critical to understand the physical mechanisms underlying the impacts of human and natural activities on the large-scale flow. To investigate this, the group uses theoretical understanding of the large-scale climate dynamics and thermodynamics states and examines observations and state-of-the-art climate models in historic and future periods.
 

A Bio and Geo Journey Through Microbial Interactions
In marine ecosystems, the interactions between microalgae and heterotrophic bacteria shape nutrient fluxes and the long-term burial of biogenic material in the ocean. These interactions have been occurring for millions of years. To better understand the mechanisms behind algal-bacterial interactions and their role in the environment, the group develops reduced model systems with adjustable complexity. By studying these model systems they can gain insight into molecular and genetic aspects of algal-bacterial ecophysiology.

Isotope Geochemistry and Paleoclimate
The group’s research is in the general field of low temperature geochemistry of sedimentary rocks, with a focus on paleoceanography and continental paleoclimate. The main objective is to understand and quantify past global changes that have occurred in the oceans and the continents on different time scales. The group develops and applies new geochemical tools that can serve as tracers of past environmental conditions and processes in the aquatic system, with the view that actual field measurements of materials that store information about natural systems in the past provide the basis for understanding climate variability and for testing models and hypotheses in the fields of Earth Science.