Sea surface temperature intercomparison in the framework of the Copernicus Climate Change Service (C3S)

A joint effort between the Copernicus Climate Change Service (C3S) and the Group for High Resolution Sea Surface Temperature (GHRSST) has been dedicated to an intercomparison study of eight global gap-free Sea Surface Temperature (SST) products to assess their accurate representation of the SST relevant to climate analysis. In general, all SST products show consistent spatial patterns and temporal variability during the overlapping time period (2003-2018). The main differences between each product are located in western boundary current and Antarctic Circumpolar Current regions. Linear trends display consistent SST spatial patterns among all products and exhibit a strong warming trend from 2012 to 2018 with the Pacific Ocean basin as the main contributor. SST discrepancy between all SST products is very small compared to the significant warming trend. Spatial power spectral density shows that the interpolation into 1o spatial resolution has negligible impacts on our results. The global mean SST time series reveals larger differences among all SST products during the early period of the satellite era (1982-2002) when there were fewer observations, indicating that the observation frequency is the main constraint of the SST climatology. The maturity matrix scores, which present the maturity of each product in terms of documentation, storage, and dissemination but not the scientific quality, demonstrate that ESA-CCI and OSTIA SST are well documented for users' convenience. Improvements could be made for MGDSST and BoM SST. Finally, we have recommended that these SST products can be used for fundamental climate applications and climate studies (e.g. El Nino)

Dynamic estimation in computational vision

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1992.Includes bibliographical references (leaves 213-220).by Toshio Michael Chin.Ph.D

Feature and contour based data analysis and assimilation in physical oceanography

The goal of this contribution is to summarize current research in physical oceanography on identifying, analyzing, modeling, or assimilating (into numerical ocean models) coherent structures seen in data. The structures considered here are dynamical features such as vortices and fronts, sets of contour positions, and the location of property extrema. The key analysis assumption allows the structure present in the data to determine the coordinate system for analyzing the data. Recent developments in the last decade are emphasized here rather than attempting a thorough historical review. Also because of space limitations, only the aspects central to our theme from the quoted studies will be noted. Because of the authors’ research interests, examples will focus on meso- and large-scale phenomena in the Northwest Atlantic Ocean

Stochastic Petri Net Modeling of Wave Sequences in Cardiac Arrhythmias

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Stochastic boundary conditions for coastal flow modeling

Recent high‐resolution radar data of surface velocity between the Florida Current and the coast allow us for the first time to deduce coastal boundary conditions for ocean models based on observations. A stochastic model is found to be a better choice for simulating properties of the observed vorticity than a model with deterministic boundary conditions. A stochastic model parameterizing boundary conditions is developed and embedded in a simple quasigeostrophic ocean model. Comparison of numerical simulations of western boundary flow with stochastic boundary conditions against simulations with traditional no‐slip and free‐slip conditions reveals significant differences in the formation of coherent mesoscale structures and the energetics of the western boundary current. Coherent structures such as dipoles and submesoscale vortices can be generated using stochastic boundary conditions. The boundary current variability becomes more energetic and “episodic” than quasi‐periodic circulation features in the simulations using the conventional boundary conditions