Formation and Destruction of Arctic Thermohaline Staircases

Abstract

This study explores the dynamics of diffusive convection, which is realized in regions where cool and fresh water-masses rest on top of those that are warm and salty. This type of convection is often observed in the Arctic Ocean and is characterized by the development of fine-scale steps in vertical salinity and temperature profiles known as thermohaline staircases. The Arctic staircases control the rate of upward heat transfer from waters of Atlantic origin, thereby influencing the melting of sea-ice and the polar climate in general. This thesis aims to utilize numerical modeling to define conditions that are favorable or unfavorable for creating thermohaline staircases and provide an explanation as to why they are not constantly prevalent throughout the Arctic. In particular, the presented high-resolution simulations explore the role of vertical shear associated with internal waves that are ubiquitous in the World Ocean. While previous investigations suggested that the vertical shear could adversely affect staircases, this effect has not been quantified and physical mechanisms at play are still poorly understood. The present study addresses these unresolved problems in the theory of double-diffusive convection, concurrently shedding light on the mechanics of heat transfer in high-latitude oceans.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 2021
Accession Number
AD1150369

Entities

People

  • Kristen Ainslie

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Arctic Ocean
  • Climate Change
  • Diffusion
  • Fluid Dynamics
  • Fluid Mechanics
  • Heat Flux
  • Heat Transfer
  • Internal Waves
  • Mechanics
  • Oceanography
  • Oceans
  • Richardson Number
  • Temperature Gradients
  • Three Dimensional
  • Turbulence
  • Turbulent Mixing
  • Two Dimensional

Fields of Study

  • Environmental science

Readers

  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Polar and Arctic Studies
  • Theoretical Analysis.