CASPO

Talk Abstract:

In many parts of the global ocean, density compensated temperature (T) and salinity (S) anomalies, known as ocean spice, highlight processes that interleave, stir and eventually mix water from different sources. The unique spatial and temporal structure of upper ocean spice patterns is set by the large-scale dynamics and the balance between different frontal processes, such as subduction, turbulent mixing, and atmospheric forcing that create, distribute and destroy spice. Spice variability also plays a substantial role…

Talk Abstract: TBA

The climate system involves a variety of nonlinearly interacting physical processes spanning a broad range of spatial and temporal scales. To make simulations of the climate system computationally tractable, processes with scales smaller than the typical grid size of climate models have to be parameterized. Recently, there has been substantial interest (and progress) in using deep learning techniques to develop data-driven subgrid-scale (SGS) parameterizations for a number of key processes in the atmosphere, ocean, and other…

Talk Abstract:

Coastal groundwater is important to freshwater resources, ecosystem health, pollutant transport, and flooding in coastal communities. The evolution of groundwater levels, circulation, and salinities is affected by ocean tides, storm surges, and waves, the beach morphology, and aquifer properties. Meanwhile, the exchange of water between the ocean and the aquifer can affect sediment transport and surface water chemistry. Despite significant progress over the past decades, groundwater processes in and near the shoreline are not understood well. Here, the…

Talk Abstract:

Small-scale turbulent mixing in the ocean interior is believed to play an important role in the ocean circulation and the tracer distributions within. However, the extent to which the fluid dynamical subtleties of mixing impact the climate system, remains poorly quantified. Building on a number of case studies, in this talk, I will argue that on annual to millennial timescales, small-scale mixing is of leading-order importance for the ocean meridional overturning circulation (MOC), its internal variability, and tracer…

Talk Abstract:

Near-Inertial Internal Waves (NIWs) play a key role in the ocean circulation energy balance but their dynamics is challenging.  Because NIW dynamics requires synoptic sampling at very high vertical resolution this is only a partially resolved topic in oceanography. Here, I present results from a multi-platform, multi-scale and multi-disciplinary campaign led by the NATO Centre for Maritime Research and Experimentation in the Ligurian Sea (Northwestern Mediterranean Sea) from September to November 2017. The…

Talk Abstact:

Tropical cyclone (TC) intensity is strongly affected by the air-sea heat flux beneath the storm. Therefore, accurate predictions of upper ocean responses (such as mixed layer deepening, upwelling, and sea surface temperature cooling) under TCs are necessary for improving TC intensity forecast. The accurate wind stress which driven upper ocean current needs to be understood more. In this study the wind stress (or the drag coefficient) into the ocean and the sea state dependence of drag coefficient (Cd) under tropical cyclones is investigated. The…

Note: This is a joint seminar hosted with Caltech and UCLA

Talk abstract:

Mesoscale eddies contain the bulk of the ocean’s kinetic energy (KE), but fundamental questions remain on the cross-scale KE transfers linking eddy generation and dissipation. The role of submesoscale flows represents a key point of discussion, with contrasting views of submesoscales as either a source or a sink of mesoscale KE. Here, the first observational assessment of the annual cycle of the KE transfer between mesoscale and…

Talk abstract:

Global atmospheric `storm-resolving' models with horizontal grid spacing of less than ~5km resolve deep cumulus convection and flow in complex terrain. While computationally expensive, they can be run for yearlong scales and can serve as reference models for improving more economical coarse-grid global weather and climate models. Machine learning (ML) offers an avenue for translating the patterns seen in storm-resolving models onto the coarser grid, with the ultimate goal of reducing uncertainties in regional precipitation and temperature trends in global…

Talk Abstract: TBA

Talk Abstract:

While much attention has been given to understanding how anthropogenic greenhouse gas emissions influence the mean state of the climate system, far less scrutiny has been paid to how they may modulate naturally occurring modes of climate variability.  In this talk, I will present a new analysis of projected changes in the patterns and amplitudes of atmospheric circulation variability over the North Pacific and North America based on a novel set of global climate model simulations. As climate change…