Pierre-Marie Poulain | Istituto Nazionale di Oceanografia e Geofisica Sperimentale (original) (raw)

Papers by Pierre-Marie Poulain

Journal of Geophysical Research: Oceans, 2013

Winter convection occurred during 2012 in the Northern Adriatic produced an exceptionally dense w... more Winter convection occurred during 2012 in the Northern Adriatic produced an exceptionally dense water, which caused abrupt thermohaline changes in the bottom layer of the Southern Adriatic after its arrival as a bottom-arrested current. We investigate this phenomenon merging data from a fixed point observatory and from drifting profiling Argo floats.

Deep Sea Research Part A. Oceanographic Research Papers, 1989

... onshore-flowing filament of the California Current PEARN P. Nm,ER,* PIERRE-MARIE POULAIN* and... more ... onshore-flowing filament of the California Current PEARN P. Nm,ER,* PIERRE-MARIE POULAIN* and ... Scripps Institution of Oceanography, University of California, San Diego, La Julia ... flowing subarctic water is its subsurface salinity minimum (REID et al., 1958; LYNN and SrM ...

ABSTRACT The vorticity balance in the upper layer of the Black Sea is analyzed using several data... more ABSTRACT The vorticity balance in the upper layer of the Black Sea is analyzed using several data sources (drifter data, Argo float CTD profiles, satellite sea level anomalies and ocean surface wind velocities) in order to estimate the respective contribution of each term in the vorticity equation. The tube stretching term induces positive vorticity in all the regions of the Black Sea and seems to play an important role in the vorticity balance of the basin. 1 1 1 1 1 Vorticity is an important descriptive feature of ocean dynamics, whose variations are related to the balance of external forcing, associated with wind-stress, and internal processes. Internal processes produce vorticity variations through adjustment of internal pressure gradients (i.e. baroclinic adjustment) and/or through variations in the depth of the tube flow (tube stretching). The Black Sea is a typical marginal, semi-enclosed, dilution basin characterized by a stable stratification, a simple basin geometry and a smooth bottom topography; therefore, it is the ideal location to study the relative contribution of the different terms to the vorticity balance in the ocean and to analyze fundamental hydrodynamic interactions common to different areas of the World Ocean.

ABSTRACT The observations provided by oceanographic remote instruments are essential for the purp... more ABSTRACT The observations provided by oceanographic remote instruments are essential for the purposes of the operational oceanography, nowadays a constantly growing and powerful tool to monitor, analyze and predict the state of the marine resources as well as the sustainable development of coastal areas [1]. Near real time (NRT) observations at the sea surface and in the water column, e.g., temperature and salinity (T/S) profiles, are of central importance for the operational forecasting system in the Mediterranean Sea. The management of the network of floats deployed in the Mediterranean Sea and handled by the MedArgo Regional Argo Centre at OGS [2][3] is a complex task that may be greatly supported by the fast developing ICT infrastructures. Such workflow includes the communication system, the data downloading and treatment, the post-processing and the visualization of the information gathered by the observations. GRID technology may greatly help in providing a remote control of the entire flow of information associated with the observational instruments, from the raw data measured by the sensor at sea (i.e. temperature, salinity, current velocity) to the data-processing software running on the researcher's laptop. In particular, interactive applications of the GRID technology could support the management of the complex workflow related to the instrument interconnections (i.e. buoys, floats, autonomous vehicles), to the eventual technical problems bound to appear intermittently and the subsequent NRT corrections and/or adjustments of the sensors. Moreover, the communication to operative structures such as the Civil Protection, Coast Guards or local/regional administrations represents a composite multi-task process that involves different actors and that could be successfully integrated in a GRID environment. We will present the activity done so far and planned in the framework of the DORII EU-FP7 project [4] concerning the GRID integration of the MedArgo floats managed by OGS. The main goal of DORII is the deployment of an eInfrastructure for those scientific communities where ICT technology and the concept of GRID is perceived as a big opportunity to boost their research but that, at present, results not fully exploited. The oceanographic community may greatly benefit from the resources being offered by the GRID technology, in particular concerning the data driven control/interaction workflow and the post-processing/visualization issues that characterize the remote instruments. [1] N.C. Flemming, S. Vallerga, N. Pinardi, H.W.A. Behrens, G. Manzella, D. Prandle and J.H. Stel (eds), Operational Oceanography - Implementation at the European and Regional Scales, Elsevier Oceanography Vol. 66. Elsevier, Amsterdam (2002). [2] http://poseidon.ogs.trieste.it/sire/medargo [3] P.-M. Poulain, R. Barbanti, J. Font, A. Cruzado, C. Millot, I. Gertman, A. Griffa, A. Molcard, V. Rupolo, S. Le Bras and L. Petit de la Villeon, MedArgo: a drifting profiler program in the Mediterranean Sea, Ocean Science 3, 379-395 (2007). [4] http://www.dorii.eu/home

Different combinations of the EGM2008 global model and the GOCE spacewise solution are used to es... more Different combinations of the EGM2008 global model and the GOCE spacewise solution are used to estimate the geodetic mean dynamic topography and the corresponding surface geostrophic circulation of the Mediterranean Sea. In order to assess the accuracy of the GOCE-derived products for oceanographic applications, the mean currents obtained from the geoid models are compared with the mean surface geostrophic velocities measured by drifters and satellite altimetry data. The mean dynamic topographies based on GOCE data combined with EGM2008 generally describe the main circulation patterns and dynamical features in the Mediterranean Sea, except in few coastal regions and in the semi-enclosed Adriatic and Aegean Seas, and improve the results obtained with previous geoid models. The root mean square differences between the geostrophic velocities and the GOCE/EGM2008derived currents are smaller than 10 cm/s in all the sectors of the Mediterranean basin, whereas they are larger than 12-15 cm/s using the EGM2008 solution. The minimum discrepancies and the best complex correlation coefficient are achieved from the EGMSPWbc solution based on an order-wise block diagonal approximation of the GOCE error covariance structure.

Physical Oceanography of the Adriatic Sea, 2001

Eos, Transactions American Geophysical Union, 2005

CIESM Congress, 2010

... P. Poulain *, R. Gerin , M. Menna , I. Taupier-Letage , C. Millot , S. Ben Ismail , C. Sammar... more ... P. Poulain *, R. Gerin , M. Menna , I. Taupier-Letage , C. Millot , S. Ben Ismail , C. Sammari , G. Zodiatis and I. Gertman Istituto Nazionale di ... Current), the other one located in the central and northern portion of the region, corresponding to the Atlantic Ionian Stream (AIS) [2, 3 ...

Remote Sensing of Environment, 2006

An extensive set of in situ temperature data collected by surface drifters is combined with satel... more An extensive set of in situ temperature data collected by surface drifters is combined with satellite-derived sea surface temperature images to study the difference between the pseudo-bulk and bulk temperatures (ΔTpb–b) in the Adriatic Sea for the period 21 September 2002–31 December 2003. The variations of this temperature difference are described as a function of local wind speed and incoming

Ocean Science, 2014

This paper is the outcome of a workshop held in Rome in November 2011 on the occasion of the 25th... more This paper is the outcome of a workshop held in Rome in November 2011 on the occasion of the 25th anniversary of the POEM (Physical Oceanography of the Eastern Mediterranean) program. In the workshop discussions, a number of unresolved issues were identified for the physical and biogeochemical properties of the Mediterranean Sea as a whole, i.e., comprising the Western and Eastern sub-basins. Over the successive two years, the related ideas were discussed among the group of scientists who participated in the workshop and who have contributed to the writing of this paper. Three major topics were identified, each of them being the object of a section divided into a number of different sub-sections, each addressing a specific physical, chemical or biological issue: 1. Assessment of basin-wide physical/biochemical properties, of their variability and interactions. 2. Relative importance of external forcing functions (wind str...

Ocean Dynamics, 2012

plying analyses and forecasts of the ocean currents at unprecedented time and space resolution. U... more plying analyses and forecasts of the ocean currents at unprecedented time and space resolution. Using the Lagrangian approach, each particle displacement is described by an average motion and a fluctuating part. The first one represents the advection associated with the Eulerian current field of the circulation models while the second one describes the sub-grid scale diffusion. The focus of this study is to quantify the sub-grid scale diffusion of the Lagrangian models written in terms of a horizontal eddy diffusivity. Using a large database of drifters released in different regions of the Mediterranean Sea, the Lagrangian sub-grid scale diffusion has been computed, by considering different regimes when averaging statistical quantities. In addition, the real drifters have been simulated using a

Journal of Geophysical Research, 2010

This paper focuses on the study of the Tyrrhenian Sea, a sub-basin of the western Mediterranean w... more This paper focuses on the study of the Tyrrhenian Sea, a sub-basin of the western Mediterranean whose surface and near surface dynamics are still relatively poorly known, in particular as to its southern region. Its circulation is described first by a set of 53 surface drifters deployed in the area between December 2001 and February 2004. In order to supplement the drifter data with continuously and uniformly sampled observations, and to characterize the seasonal, as well as higher frequency variability of the surface circulation, the Lagrangian analysis was associated to simultaneous satellite remotely-sensed altimeter, covering the period 2001-2004. The investigation was based on trajectory analysis and on the computation of the pseudo-Eulerian statistics using the same binning and space-time averaging for drifter and altimeter data. The data reveal a complex pattern of the circulation, especially in the southern region of the Tyrrhenian, dominated by semipermanent recirculations and transient features which sometimes make it difficult to identify a consistent mean flow, while the northern sub-basin is characterized by a pair composed by a cyclonic and anticyclonic circulations known in the literature as North Tyrrhenian Cyclone and North Tyrrhenian Anticyclone. The pseudo-Eulerian statistics computed with the two datasets evidenced the representativeness of a joint analysis of altimeter and drifter data and yielded useful indications about proper preliminary pre-processing and resampling procedures, so as to make the comparison statistically sound.

Journal of Geophysical Research, 2008