Biogeochemical ocean-atmosphere transfers

The redox state of Earth’s atmosphere has undergone a dramatic shift over geologic time from reducing to strongly oxidizing, and this shift has been coupled with changes in ocean redox structure and the size and activity of Earth’s biosphere. Delineating this evolutionary trajectory remains a major problem in Earth system science. Significant insights have emerged through the application of redox-sensitive geochemical systems. Existing and emerging biogeochemical modeling tools are pushing the limits of the quantitative constraints on ocean–atmosphere redox that can be extracted from geochemical tracers. This work is honing our understanding of the central role of Earth’s biosphere in shaping the long-term redox evolution of the ocean–atmosphere system.

Download Full-text

A Coupled Ocean–Atmosphere System of SST Modulation for the Indian Ocean*

Journal of Climate ◽

10.1175/1520-0442(2000)013<3342:acoaso>2.0.co;2 ◽

2000 ◽

Vol 13 (19) ◽

pp. 3342-3360 ◽

Cited By ~ 76

Author(s):

Johannes Loschnigg ◽

Peter J. Webster

Keyword(s):

Indian Ocean ◽

Atmosphere System ◽

Ocean Atmosphere ◽

The Indian Ocean

Download Full-text

Frequency-Domain Analysis of the Energy Budget in an Idealized Coupled Ocean–Atmosphere Model

Journal of Climate ◽

10.1175/jcli-d-19-0118.1 ◽

2020 ◽

Vol 33 (2) ◽

pp. 707-726 ◽

Cited By ~ 1

Author(s):

Paige E. Martin ◽

Brian K. Arbic ◽

Andrew McC. Hogg ◽

Andrew E. Kiss ◽

James R. Munroe ◽

...

Keyword(s):

Frequency Domain ◽

Time Scales ◽

Energy Budget ◽

Western Boundary Current ◽

Spectral Energy ◽

Western Boundary ◽

Intrinsic Variability ◽

Boundary Current ◽

Ocean Atmosphere ◽

Atmosphere Model

AbstractClimate variability is investigated by identifying the energy sources and sinks in an idealized, coupled, ocean–atmosphere model, tuned to mimic the North Atlantic region. The spectral energy budget is calculated in the frequency domain to determine the processes that either deposit energy into or extract energy from each fluid, over time scales from one day up to 100 years. Nonlinear advection of kinetic energy is found to be the dominant source of low-frequency variability in both the ocean and the atmosphere, albeit in differing layers in each fluid. To understand the spatial patterns of the spectral energy budget, spatial maps of certain terms in the spectral energy budget are plotted, averaged over various frequency bands. These maps reveal three dynamically distinct regions: along the western boundary, the western boundary current separation, and the remainder of the domain. The western boundary current separation is found to be a preferred region to energize oceanic variability across a broad range of time scales (from monthly to decadal), while the western boundary itself acts as the dominant sink of energy in the domain at time scales longer than 50 days. This study paves the way for future work, using the same spectral methods, to address the question of forced versus intrinsic variability in a coupled climate system.

Download Full-text