Peter Cornillon

University of Rhode Island | URI · Graduate School of Oceanography

We have assembled 2 851 702 nearly cloud-free cutout images (sized 144 km × 144 km) of sea surface temperature (SST) data from the entire 2012–2020 Level-2 Visible Infrared Imaging Radiometer Suite (VIIRS) dataset to perform a quantitative comparison to the ocean model output from the MIT General Circulation Model (MITgcm). Specifically, we evaluat...

Remote sensing observations of the Earth's surface are frequently stymied by clouds, water vapour, and aerosols in our atmosphere. These degrade or preclude the measurementof quantities critical to scientific and, hence, societal applications. In this study, we train a natural language processing (NLP) algorithm with high-fidelity ocean simulations...

For over 40 years, remote sensing observations of the Earth's oceans have yielded global measurements of sea surface temperature (SST). With a resolution of approximately 1km, these data trace physical processes like western boundary currents, cool upwelling at eastern boundary currents, and the formation of mesoscale and sub-mesoscale eddies. To d...

For over 40 years, remote sensing observations of the Earth’s oceans have yielded global measurements of sea surface temperature (SST). With a resolution of approximately 1 km, these data trace physical processes like western boundary currents, cool upwelling at eastern boundary currents, and the formation of mesoscale and submesoscale eddies. To d...

The NSF Earthcube program sponsored a study of Earth Science infrastructure project sustainability. This report documents that study and its results. Eleven data infrastructure projects, most focused solely on the Earth Sciences, were studied by conducting interviews with a person who was or is currently a leader in the project. The study reveals t...

We performed an OOD analysis of ∼12,000,000 semi-independent 128x128 pixel2SST regions, which we define as cutouts, from all nighttime granules in the MODIS R2019 L2 public dataset to discover the most complex or extreme phenomena at the ocean’s surface. Our algorithm (ulmo) is a PAE, which combines two deep learning modules: (1) an autoencoder, tr...

Sea surface temperature (SST) fields obtained from the series of space-borne five-channel Advanced Very High Resolution Radiometers (AVHRRs) provide the longest continuous time series of global SST available to date (1981–present). As a result, these data have been used for many studies and significant effort has been devoted to their careful calib...

This study was undertaken to derive and analyze the advanced microwave scanning radiometer-Earth observing satellite (EOS) (AMSR-E) sea surface temperature (SST) footprint associated with the remote sensing systems (RSS) level-2 (L2) product. The footprint, in this case, is characterized by the weight attributed to each 4 × 4 km square contributing...

This study was undertaken to derive and analyze the Advanced Microwave Scanning Radiometer - EOS (AMSR-E) sea surface temperature (SST) footprint associated with the Remote Sensing Systems (RSS) Level-2 (L2) product. The footprint, in this case, is characterized by the weight attributed to each 4 4 km square contributing to the SST value of a given...

The primary measure of the quality of sea surface temperature (SST) fields obtained from satellite-borne infrared sensors has been the bias and variance of matchups with co-located in-situ values. Because such matchups tend to be widely separated, these bias and variance estimates are not necessarily a good measure of small scale (several pixels) g...

Detailed understanding of submesoscale processes and their role in global ocean circulation is constrained, in part, by the lack of global observational datasets of sufficiently high resolution. Here, the potential of thermosalinograph (TSG) and Visible Infrared Imager Radiometer Suite (VIIRS) data is evaluated, to characterize the submesoscale str...

Detailed understanding of submesoscale processes and their role in global ocean circulation is constrained, in part, by the lack of global observational datasets of sufficiently high resolution. Here, the potential of thermosalinograph (TSG) and Visible- Infrared Imager-Radiometer Suite (VIIRS) data is evaluated, to characterize the submesoscale st...

Global observations of quasi-zonal jet-like structures have recently been reported in estimates of upper ocean circulation. To date, these observations have come primarily from float- and altimeter-derived estimates of zonal velocity. Here, we explore the existence of similar structures in the ocean using satellite-derived estimates of sea surface...

Satellite-derived sea surface temperature (SST) fronts provide a valuable resource for the study of oceanic fronts. Two edge detection algorithms designed specifically to detect fronts in satellite-derived SST fields are compared: the histogram-based algorithm of Cayula and Cornillon (1992, 1995) and the entropy-based algorithm of Shimada et al. (2...

[1] Distinct 4 year averages of absolute dynamic topography reveal striations in all ocean basins during 1993–2008. Striations are alternating mesoscale jet-like structures observed in time-averaged zonal geostrophic velocity, . They are characterized by speeds O(1 cm s–1) and are nominally separated by 200 km in the meridional direction. Similar p...

The derivation of sea-surface temperatures (SST) from space-borne measurements from both infrared and microwave radiometers is now a relatively mature subject and the global and regional SST fields have many applications in operational weather and ocean forecasting, and in research into the processes of the climate system. Successful application of...

Organizing online data presents a number of challenges, among which is keeping their inventories current. It is preferable to have these descriptions built and maintained by automated systems because many online data sets are dynamic, changing as new data are added or moved and as computer resources are reallocated within an organization. Automated...

Scientific method and the influence of technology: Due to the increasing number and sophistication of data acquisition technologies, the amount of raw data acquired has vastly increased over the last couple of decades (Berman, 2008). This explosion of scientific data, growth in scientific knowledge, and the increase in the number of studies that re...

The OPeNDAP Data Access Protocol (DAP) provides interoperable access to a large number of Earth science data sets at the data level ; i.e., once a data archive of interest has been located and its structure determined, access to the data is relatively straightforward. At its core, the DAP is discipline neutral: it requires a rigid description of th...

With origins dating back to 1990, the Advanced Very High Resolution Radiometer (AVHRR) Pathfinder Sea Surface Temperature (SST) Program has experienced a 20-year history of reprocessing space- based observations to create accurate, consistent, climate data records. Both scientific and programmatic aspects of this history are reviewed and summarized...

Environmental sensor networks are now commonly being deployed within environmental observatories and as components of smaller-scale ecological and environmental experiments. Effectively using data from these sensor networks presents technical challenges that are difficult for scientists to overcome, severely limiting the adoption of automated sensi...

Sea Surface Temperature (SST) at the ocean-atmosphere interface is a fundamental variable for understanding, monitoring and predicting fluxes of heat, momentum and gas at a variety of scales from local to global climate that determine complex interactions between atmosphere and ocean. This paper has been prepared for those implementing and working...

: The AVHRR SST Pathfinder Project began in 1991 with the initial formulation of Version 1. Over the years, improvements have been introduced, e.g. product resolution, quality testing, navigation and SST retrieval accuracy, that have led to a series of versions covering the NOAA-7 through NOAA-18 (1981-present) satellites. During this period Pathfi...

The GODAE (Global Ocean Data Assimilation Experiment) project has operated for a decade to establish a common definition and description of what is a GODAE ocean data product, and tuned each production center to routinely serve quality-controlled ocean data. A legacy of GODAE has been in harmonizing the various products and the development of essen...

The Global Ocean Data Assimilation Experiment (GODAE [http://www.godae.org]) has spanned a decade of rapid technological development. The ever-increasing volume and diversity of oceanographic data produced by in situ instruments, remote-sensing platforms, and computer simulations have driven the development of a number of innovative technologies th...

During the past five to ten years, a broad partnership of institutions under NOPP sponsorship has collaborated in developing and demonstrating the performance and application of eddy-resolving, real-time global- and basin-scale ocean prediction systems using the HYbrid Coordinate Ocean Model (HYCOM). The partnership represents a broad spectrum of t...

The National Oceanographic Partnership Program (NOPP) funded a project to develop the foundation for a National Virtual Ocean Data System (NVODS) that has resulted in a robust data access framework for the exchange of oceanographic data (the Open source Project for a Network Data Access Protocol, or OPeNDAP) and a broad community of ocean data prov...

Oceanic fronts shape marine ecosystems; therefore front mapping and characterization are among the most important aspects of physical oceanography. Here we report on the first global remote sensing survey of fronts in the Large Marine Ecosystems (LME). This survey is based on a unique frontal data archive assembled at the University of Rhode Island...

Air–sea interaction at ocean fronts and eddies exhibits positive correlation between sea surface temperature (SST), wind speed, and heat fluxes out of the ocean, indicating that the ocean is forcing the atmosphere. This contrasts with larger scale climate modes where the negative correlations suggest that the atmosphere is driving the system. This...

The ability of HYCOM, an eddy-resolving ocean circulation model, to properly simulate the distribution of fronts in the upper ocean is evaluated using satellite-derived SST fields obtained from the MODIS spectro-radiometer. Although the HYCOM simulations are global, the analysis presented here was for the North Atlantic only. The MODIS data were re...

Western boundary current separation has long been a mystery. For the Gulf Stream, different factors such as the coastal shape, inflow and outflow location, wind stresses, continental shelf slope, shallow underwater plateaus, and interaction with the deep circulation potentially play unique and important roles in separating the Gulf Stream from the...

[1] The characteristics of surface temperature (SST) fronts in the subtropical frontal zone (STCZ) in the North Atlantic were investigated using a time series of front data produced by an edge-detection algorithm applied to 18 years of 9.3 km resolution NOAA/NASA AVHRR Pathfinder SST imagery. Front probability, averaged over subregions of the STCZ,...

Oceanic fronts shape marine ecosystems; therefore front mapping and characterization is one of the most important aspects of physical oceanography. Here we report on the first effort to map and describe all major fronts in the World Ocean's Large Marine Ecosystems (LMEs). Apart from a geographical review, these fronts are classified according to th...

[1] The response of surface winds to ocean fronts characterized by sharp gradients in both sea surface temperature (SST) and ocean currents was analyzed using scatterometer (NSCAT and QuikSCAT) wind data and Gulf Stream path positions in conjunction with simulations made with the Pennsylvania State University (PSU)-National Center for Atmospheric R...

The OPeNDAP Data Access Protocol (DAP) is a community standard for sharing scientific data across the Internet. Data providers using DAP have adopted a variety of metadata conventions to improve data utility, such as COARDS (1995) and CF (2003). Our results show, however, that metadata do not follow these conventions in practice. We collected metad...

1] The relationship between cold surface water along the Primorye coast and sea ice in the Tatar Strait of the northern East Sea (the Sea of Japan) is examined by analyzing sea surface temperatures (SST) from NOAA/AVHRR, sea ice concentrations from SSM/I, wind vectors from QuikSCAT, and position data from satellite-tracked drifting buoys. Relativel...

1] Modifications to surface winds by currents and sea surface temperature (SST) gradients near frontal boundaries of Gulf Stream rings are analyzed using satellite SST and scatterometer (NASA's Quick Scatterometer (QuikSCAT), NASA scatterometer (NSCAT)) wind observations. A component of scatterometer wind approximately equal and opposite to the sur...

The notion of an end-to-end data system has become blurred in today's rapidly evolving environment of distributed data system elements. In this presentation, we investigate the data system integrator as the defining element of an end-to-end data system. The data system integrator provides data discovery and delivery within the user's analysis envir...

In this presentation we explore two efforts designed to promote interoperability between the OPeNDAP data access protocol and the OGC WFS and WCS protocols. The first is based on MapServer, an open-source development environment for building spatially-enabled Internet applications. Among other things, MapServer may be used as an OGC WFS and WCS ser...

The relationship between the annual cycle of sea surface temperature (SST) in the East (Japan) Sea and wind forcing and bathymetry is examined using AVHRR-derived SST fields and satellite-derived scatterometer wind fields. On the basin scale, SST north of the Subpolar Front (SPF) is characterized by relatively larger amplitude (>=10°C) and variance...

Thermal fronts were studied from Pathfinder satellite SST fields, 1985-1996, obtained from AVHRR 9-km resolution twice-daily images (8,364 images in total). Fronts were detected from each image using the Cayula-Cornillon edge detection and cloud masking algorithms. Long-term (1985-1996) frontal frequencies (normalized on cloudiness) were computed f...

The OPeNDAP data access protocol is in increasing use for remote access to data in oceanography, meteorology, land cover studies and the space sciences. At the same time there is increasing use in the geographic information science (GIS) community of protocols to remotely access data. The fundamental difference between the two approaches for remote...

The notion of an end-to-end data system has become blurred in today's rapidly evolving environment of distributed data system elements. In this presentation, we investigate the data system integrator as the defining element of an end-to-end data system. The data system integrator provides data discovery and delivery within the user's analysis envir...

Simulations, made with the fifth-generation Pennsylvania State University (PSU)-National Center for At- mospheric Research (NCAR) Mesoscale Model (MM5), of the response of the marine atmospheric boundary layer (MABL) as air moves over a sharp SST front are compared with observations made during the Frontal Air-Sea Interaction Experiment (FASINEX) i...

This study uses satellite observations of sea surface height (SSH) to detect westward-propagating anomalies, presumably baroclinic Rossby waves, in the North Atlantic and to estimate their period, wavelength, amplitude, and phase speed. Detection involved a nonlinear fit of the theoretical dispersion relation for Rossby waves to the time-longitude...

Management and communication of marine environmental data present special challenges due to the variety and complexity of the observations and products. Marine environmental data include not only physical measurements of the ocean and sea surface interface, but also biological (e.g. species sitings and surveys), geological (e.g. bottom type), chemi...

Data access protocols on which many emerging data systems are being based are often tightly coupled with the semantics of the discipline for which the system is being developed. This greatly facilitates interoperability within the data system, but it also generally results in substantial constrains on interoperability with data systems in other dis...

In the process of implementing a protocol for the transport of science data, the Open Source Project for a Network Data Access Protocol (OPeNDAP) group has learned a considerable amount about the internal anatomy of what are commonly considered monolithic concepts. In order to communicate among our group, we have adopted a collection of definitions...

Central to the vision of the U.S. Integrated Ocean Observing System (IOOS) is a data management infrastructure that joins Federal, regional, state, municipal, academic, and commercial partners in a seamless data-sharing framework. The Data Management and Communications (DMAC) Subsystem of IOOS must be capable of integrating the full spectrum of mar...

Interpretation of sea surface height anomaly (SSHA) and wind forcing of first baroclinic mode Rossby waves is considered using linear inviscid long-wave dynamics for both the standard and surface-intensified vertical mode in a continuously stratified rest-state ocean. The ratio between SSHA variance and vertically integrated energy of waves is prop...

The Pathfinder AVHRR SST data from 1985–1996 are used to survey thermal fronts of the Pacific coastal and marginal seas. The SST fields are declouded and fronts are detected with the Cayula-Cornillon algorithms developed at the URI. In this work we describe newly found, persistent frontal features and their seasonal variability as well as interannu...

1] Satellite-borne scatterometer and infrared data collected over Gulf Stream warm and cold core rings are used to study the effect of the sea-air temperature difference on the wind speed over rings. The observed acceleration of the wind over and deceleration overis found to be consistent with that predicted by the planetary boundary layer model of...

Larval fish originating south of Cape Hatteras, North Carolina, are frequently found on the continental shelf north of Cape Hatteras, even as far north as the Scotian shelf. The Gulf Stream and associated warm-core rings are hypothesized as the physical mechanisms responsible for the northward transport of larvae. Specifically, larvae spawned along...

The North Atlantic Subtropical Mode Water (STMW) layer was identified based on its temperature, large thickness, and small temperature gradient. Comparisons between this method and identifying the STMW layer using a density-based (i.e., potential vorticity) criteria indicate that this method successfully identifies the STMW layer as the remnant of...

Individual sea surface temperature (SST) anomalies are calculated using a satellite-based climatology and observations from the World Ocean Atlas 1994 (WOA94) and the Comprehensive Ocean-Atmosphere Data Set (COADS) to characterize global and regional changes in ocean surface temperature since 1942. For each of these datasets, anomaly trends are com...

Subtropical mode waters (STWMs) are water masses formed in winter by convective mixing on the equatorward side of western boundary currents in the subtropical gyres. After the return of the seasonal stratification in spring, it is found at the stratification minimum between the seasonal and main pycnoclines. By characterizing STMW primarily at the...

Analysis of 12 years (1985–1996) of sea surface temperature (SST) imagery covering the shelf and slope off the northeast US coast has revealed the presence of persistent fronts in winter over the middle shelf. Ongoing work shows that similar fronts occur in other coastal regions, suggesting that these fronts are of more than regional interest. The...

The collaborative analysis of data within the Space Physics community is hindered, in part, by the wide number of data formats and the wide distribution of data archives. In an attempt to address these two problems we have implemented a prototype which retrieves datasets, stored in different data formats at several remote locations. Our prototype u...

The NASA scatterometer, NSCAT, was designed to estimate from space the wind velocity relative to the ocean surface velocity. Assuming that the spatial scale of the meteorological forcing giving rise to the wind is large compared with the diameter of a warm core ring, it should be possible to obtain information about the currents in the ring from th...

Sea surface temperature (SST) fronts detected in Advanced Very High Resolution Radiometer (AVHRR) data using automated edge-detection algorithms were compared to fronts found in continuous measurements of SST made aboard a ship of opportunity. Two histograms (a single-image and a multi-image method) and one gradient algorithm were tested for the oc...

Front detection and declouding algorithms de-veloped at the URI have been applied to the 12-year (1985-1996) Pathfinder SST data set to produce the first com-prehensive, objectively derived, year-round climatology of ocean thermal fronts in the eastern China Seas, from 24 • N to 41 • N. Ten fronts have been distinguished, namely Kuroshio, Zhejiang-...

Meanders of the shelf break front in the Mid-Atlantic Bight (MAB) during April and May of 1997 were associated with chlorophyll enhancement along a hydrographic and a topographic feature. The hydrographic feature was the surface outcrop of the front, which ranged from ~10 to >100 km seaward of the shelf break owing to the meanders. The topographic...

The distribution and variability of sea surface temperature (SST) fronts, over the shelf and slope along the east coast of North America from Cape Hatteras to Nova Scotia, are studied using a 12 year time series (1985–1996) of advanced very high resolution radiometer (AVHRR) images. After the masking of cloud-contaminated pixels, an edge-detection...

The distribution and variability of sea surface temperature (SST) fronts, over the shelf and slope along the east coast of North America from Cape Hatteras to Nova Scotia, are studied using a 12 year time series (1985-1996) of advanced very high resolution radiometer (AVHRR) images. After the masking of cloud-contaminated pixels, an edge-detection...

The purpose of this study is to present a satellite-derived sea surface temperature (SST) climatology based on Pathfinder Advanced Very High Resolution Radiometer (AVHRR) data and to evaluate it and several other climatologies for their usefulness in the determination of SST trends. The method of evaluation uses two long-term observational collecti...

In 8 yr (1979-1986) of Coastal Zone Color Scanner (CZCS) imagery, we find annual enhancement of chlorophyll at the shelfbreak of the Mid-Atlantic Bight (MAB) and Georges Bank during the spring transition from well-mixed to stratified conditions. Spatial and temporal extents of enhancement vary interannually, and expression is inter- mittent intraan...

The distribution and variability of surface temperature fronts in the Great Lakes is studied using an 11 year time series (1985 to 1995) of Advanced Very High Resolution Radiometer (AVHRR) images. After the removal of cloud contaminated pixels as well as those potentially ice covered, an edge detection algorithm identifies surface temperature front...

Residual sea surface height anomaly fields are obtained over the North Atlantic Basin from TOPEX/POSEIDON altimeter data. Evidence of westward propagating anomalies characterized as first-mode baroclinic Rossby waves is presented. The phase speeds are obtained from the analysis of the autocorrelation matrices of the residual surface height anomaly...

As part of the National Aeronautic and Space Administration's and the National Oceanic and Atmospheric Administration's Pathfinder program in the United States, all of the five-channel Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) data for the globe are being reprocessed to a consistent set of sea surface temperature (...

The Karhunen‐Loève decomposition is used to analyze time records of AVHRR sea surface temperature observations of the Western North Atlantic. A manually declouded dataset covering the spring of 1985 is analyzed. The majority (80%) of the variance about the mean is accounted for by an empirical eigenfunction which is identified with seasonal warming...

Analysis of the Gulf Stream path between 75° and 60°W indicates that the spectral signature of propagating and standing meanders is qualitatively similar to that observed for the upstream region 74°-70°W. Progressive, retrogressive, and standing meanders coexist at periods of several months and longer. The amplitude-dependent dispersion relation ob...

Positions of the Gulf Stream path from 74° to 45°W were obtained from satellite infrared images for the period of April 1982-December 1989. The propagation of meanders between 74° and 70°W was studied through spectral analysis in wavenumber-frequency space, empirical orthogonal function analysis in time and frequency domains, and direct measurement...

A cloud detection algorithm was designed as an adjunct to a companion edge-detection algorithm. The cloud detection integrates two distinct algorithms: one based on multiimage processing, the other on single-image analysis. The multiimage portion of the cloud detection algorithm operates on a time sequence of sea surface temperature (SST) images. I...

The data used for this analysis are path displacements of the Gulf Stream between 75° and 60°W obtained from AVHRR-derived infrared images for April 1982 December 1989. Meandering intensity displays a 9-month dominant periodicity which may be related to the interaction of Rossby waves with the stream. Interannual variation of meandering intensity i...

Ocean fronts are narrow zones of intense dynamic activity that play an important role in global ocean– atmosphere interactions. Owing to their highly variable nature, both in space and time, they are notoriously difficult features to adequately sample using traditional in situ techniques. In this paper, the authors propose a new statistical modelin...

Presents a small sample of the lesson plans developed as a result of a summer workshop that allowed a high school physics teacher to explore the uses of satellite-derived sea surface temperature fields in the physical science classroom. (ZWH)

Eight years of Gulf Stream data were examined to determine the percentage of meander crests that give rise to warm core rings. A lower bound of 0.24 could be placed on the probability that a meander crest detaches to form a warm core ring. This was obtained by considering all disturbances in the path of the Gulf Stream that could be tracked over a...

A combination of water masses was observed over the continental slope between Cape Hatteras and Hudson Canyon following the passage of a Gulf Stream meander. It was largely made up of fluid discharged from the Gulf Stream in the wake of the meander and also contained intrusions of Middle Atlantic Bight (MAB) shelf water and slope water. Its most pr...

Software that allows remote users to browse satellite-derived images and in-situ data archives of interest to oceanographers via Internet has been developed by researchers at the University of Rhode Island/s Graduate School of Oceanography. The tool, called ``Xbrowse,'' can access a recently assembled archive of Advanced Very High Resolution Radiom...

Investigates the validity of the separation hypothesis introduced by Parsons (1969) and extended by Veronis (1973). A detailed exposition of the Parsons-Veronis hypothesis is presented, followed by a discussion of the datasets used for this study. A two-layer model of the North Atlantic at approximately 35°N is established and the selection of the...

An algorithm to detect fronts in satellite-derived sea surface temperature fields is presented. Although edge detection is the main focus, the problem of cloud detection is also addressed since unidentified clouds can lead to erroneous edge detection. The algorithm relies on a combination of methods and it operates at the picture, the window, and t...