Anand Gnanadesikan

About

Anand Gnanadesikan trained as an oceanographer with primary expertise in how the ocean circulates and influences marine life, climate, and atmospheric chemistry. He earned his PhD from the MIT/Woods Hole Joint Program in physical oceanography and has spent more than 15 years working at Princeton University and NOAA’s Geophysical Fluid Dynamics Laboratory developing computer models of planetary systems. Since joining the Johns Hopkins University faculty in January 2011, he has used numerical models and large datasets to explore the interactions between the ocean and the biosphere, atmosphere, and cryosphere. His research interests include the role of mixing in setting the large-scale circulation and chemical properties of the ocean, with particular focus on the impact of internal wave breaking and oceanic weather systems on vertical exchange. He investigates ocean biology and chemistry, especially oceanic tracers such as radiocarbon and open-ocean hypoxia, and how biological cycling can feedback on physical climate through alterations in the carbon cycle and ocean color. Additionally, Gnanadesikan studies variability in the Earth system, aiming to understand climate change on timescales from annual to multimillennial, with a focus on the Southern Ocean, tropical variability, and the North Atlantic.

Research topics

• Geology
• Environmental science
• Oceanography
• Atmospheric sciences
• Climatology
• Biology
• Ecology
• Meteorology
• Evolutionary biology
• Geography

Selected publications

• Interannual SAM Modulation of Antarctic Sea Ice Extent Does Not Account for Its Long‐Term Trends, Pointing to a Limited Role for Ozone Depletion

  Geophysical Research Letters · 2021 · 39 citations

  Abstract The expansion of Antarctic sea ice since 1979 in the presence of increasing greenhouse gases remains one of the most puzzling features of current climate change. Some studies have proposed that the formation of the ozone hole, via the Southern Annular Mode, might explain that expansion, and a recent paper highlighted a robust causal link between summertime Southern Annular Mode (SAM) anomalies and sea ice anomalies in the subsequent autumn. Here we show that many models are able to capt…

  DOI

• ENSO Teleconnection to Eastern African Summer Rainfall in Global Climate Models: Role of the Tropical Easterly Jet

  Journal of Climate · 2020 · 33 citations

  Senior authorCorresponding

  Abstract Global climate models (GCMs) are critical tools for understanding and projecting climate variability and change, yet the performance of these models is notoriously weak over much of tropical Africa. To improve this situation, process-based studies of African climate dynamics and their representation in GCMs are required. Here, we focus on summer rainfall of eastern Africa (SREA), which is crucial to the Ethiopian Highlands and feeds the flow of the Blue Nile River. The SREA region is hi…

  DOI

• Using Random Forests to Compare the Sensitivity of Observed Particulate Inorganic and Particulate Organic Carbon to Environmental Conditions

  Geophysical Research Letters · 2024-09-13 · 4 citations

  articleOpen access

  Abstract The balance between particulate inorganic carbon (PIC) and particulate organic carbon (POC) holds significant importance in carbon storage within the ocean. A recent investigation delved into the spatial distribution of phytoplankton and the physiological mechanisms governing their growth. Employing random forests, a machine learning technique, this study unveiled apparent relationships between POC and 10 environmental fields. In this work, we extend the use of random forests to compare…

  PublisherOA PDFDOI

• Expanding the phylogeography and connectivity of <i>Perkinsus</i> species across North and Central America

  Diversity and Distributions · 2023-12-19 · 4 citations

  articleOpen access

  Abstract Aim Parasites in the genus Perkinsus infect marine molluscs globally, with novel detections expanding and reshaping our knowledge of their biogeographic patterns and the factors influencing those patterns. Here, we aimed to characterize the phylogeography and genetic connectivity of Perkinsus spp. in bivalves across North and Central America, which included infection hot spots (e.g., the Gulf of Mexico, Chesapeake Bay) and areas where these parasites had not been previously reported (e.…

  PublisherOA PDFDOI

• Genes involved in carbon, nitrogen, and sulfur cycling in an important estuarine ecosystem show coherent shifts in response to changes in environmental conditions

  Limnology and Oceanography · 2024-11-18 · 3 citations

  articleOpen accessSenior authorCorresponding

  Abstract While metagenomics can provide insight into microbial community metabolic potential, understanding factors that influence gene abundance is necessary to maximize the information gained from this analysis. Gene abundances are influenced by chemical or physical conditions along with other factors, such as copy number variation between taxa, methodological biases, or issues associated with identification and classification. Here, we identify major drivers of spatiotemporal shifts in microb…

  PublisherOA PDFDOI

Recent grants

• Collaborative Research: Southern Ocean Convection in climate models: controls and Impacts

  NSF · $388k · 2018–2022

Frequent coauthors

• Marie‐Aude Pradal

  Johns Hopkins University

  51 shared

• John P. Dunne

  36 shared

• Jorge L. Sarmiento

  34 shared

• Stephen M. Griffies

  NOAA Geophysical Fluid Dynamics Laboratory

  33 shared

• Richard D. Slater

  Royal Alexandra Hospital

  27 shared

• Larry W. Horowitz

  National Oceanic and Atmospheric Administration

  26 shared

• H. S. Chen

  25 shared

• Antony K. Liu

  Goddard Space Flight Center

  25 shared

Similar researchers at Johns Hopkins University

• Julie K. Lundquisth-82
• Darryn Waughh-81
• Dimitri Sverjenskyh-70