scholarly journals About the seasonal and fortnightly variabilities of the Mediterranean outflow

2010 ◽  
Vol 7 (6) ◽  
pp. 2043-2058
Author(s):  
C. Millot ◽  
J. Garcia-Lafuente
Keyword(s):  
Time Series ◽  
Spatial Heterogeneity ◽  
Seasonal Variability ◽  
Internal Tide ◽  
Atlantic Water ◽  
Strait Of Gibraltar ◽  
Mediterranean Outflow ◽  
The Mediterranean

Abstract. CTD time series from the HYDRO-CHANGES programme and INGRES projects have been collected simultaneously (2004–2008) on the Moroccan shelf and at the Camarinal and Espartel Sills in the strait of Gibraltar. They provide information that supports results recently obtained from the analysis of the two former time series, as well as from a reanalysis of CTD GIBEX profiles (1985–1986). The outflow of Mediterranean Waters, which does not show a clear seasonal variability before entering the strait, strongly mixes within the strait, due mainly to the internal tide, with the seasonally variable inflow of Atlantic Water. The outflow thus gets marked seasonal and fortnightly variabilities within the strait. Furthermore, since the outflow entering the strait displays marked spatial heterogeneity and long-term temporal variabilities, predicting its characteristics when in the ocean appears almost impossible.

scholarly journals About the seasonal and fortnightly variabilities of the Mediterranean outflow

Ocean Science ◽  
2011 ◽  
Vol 7 (3) ◽  
pp. 421-428 ◽  
Author(s):  
C. Millot ◽  
J. Garcia-Lafuente
Keyword(s):  
Time Series ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Internal Tide ◽  
Atlantic Water ◽  
Strait Of Gibraltar ◽  
The North ◽  
Mediterranean Outflow ◽  
The Mediterranean

Abstract. CTD time series from the HYDRO-CHANGES programme and INGRES projects have been collected simultaneously (2004–2008) on the shelf of Morocco and at the sills of Camarinal and Espartel in the strait of Gibraltar. They provide information that supports results recently obtained from the analysis of the two former time series, as well as from a reanalysis of GIBEX CTD profiles (1985–1986). The outflow of Mediterranean Waters, which does not show a clear seasonal variability before entering the strait, strongly mixes within the strait, due mainly to the internal tide, with the seasonally variable inflow of Atlantic Water. The outflow thus gets marked seasonal and fortnightly variabilities within the strait. Furthermore, since the outflowing waters entering the strait display marked spatial heterogeneity and long-term temporal variabilities, accurately predicting the characteristics of the Mediterranean outflow into the North Atlantic Ocean appears almost impossible.

scholarly journals Recent observations of seasonal variability of the Mediterranean outflow in the Strait of Gibraltar

2007 ◽  
Vol 112 (C10) ◽  
Author(s):  
J. García Lafuente ◽  
A. Sánchez Román ◽  
G. Díaz del Río ◽  
G. Sannino ◽  
J. C. Sánchez Garrido
Keyword(s):  
Seasonal Variability ◽  
Strait Of Gibraltar ◽  
Mediterranean Outflow ◽  
The Mediterranean

scholarly journals Latest Miocene restriction of the Mediterranean Outflow Water: a perspective from the Gulf of Cádiz

2021 ◽  
Vol 41 (2) ◽  
Author(s):  
Zhi Lin Ng ◽  
F. Javier Hernández-Molina ◽  
Débora Duarte ◽  
Francisco J. Sierro ◽  
Santiago Ledesma ◽  
...  
Keyword(s):  
Mass Exchange ◽  
Water Mass ◽  
Atlantic Water ◽  
Meridional Overturning Circulation ◽  
Gulf Of Cadiz ◽  
Mediterranean Outflow Water ◽  
Gulf Of Cádiz ◽  
Mediterranean Outflow ◽  
The Mediterranean ◽  
Water Mass Exchange

AbstractThe Mediterranean-Atlantic water mass exchange provides the ideal setting for deciphering the role of gateway evolution in ocean circulation. However, the dynamics of Mediterranean Outflow Water (MOW) during the closure of the Late Miocene Mediterranean-Atlantic gateways are poorly understood. Here, we define the sedimentary evolution of Neogene basins from the Gulf of Cádiz to the West Iberian margin to investigate MOW circulation during the latest Miocene. Seismic interpretation highlights a middle to upper Messinian seismic unit of transparent facies, whose base predates the onset of the Messinian salinity crisis (MSC). Its facies and distribution imply a predominantly hemipelagic environment along the Atlantic margins, suggesting an absence or intermittence of MOW preceding evaporite precipitation in the Mediterranean, simultaneous to progressive gateway restriction. The removal of MOW from the Mediterranean-Atlantic water mass exchange reorganized the Atlantic water masses and is correlated to a severe weakening of the Atlantic Meridional Overturning Circulation (AMOC) and a period of further cooling in the North Atlantic during the latest Miocene.

scholarly journals Long-term monitoring programme of the hydrological variability in the Mediterranean Sea: a first overview of the HYDROCHANGES network

Ocean Science ◽  
2013 ◽  
Vol 9 (2) ◽  
pp. 301-324 ◽  
Author(s):  
K. Schroeder ◽  
C. Millot ◽  
L. Bengara ◽  
S. Ben Ismail ◽  
M. Bensi ◽  
...  
Keyword(s):  
Time Series ◽  
Mediterranean Sea ◽  
Sampling Interval ◽  
Global Changes ◽  
Hydrological Variability ◽  
Long Term Monitoring ◽  
The Mediterranean ◽  
Set Up ◽  
Term Monitoring

Abstract. The long-term monitoring of basic hydrological parameters (temperature and salinity), collected as time series with adequate temporal resolution (i.e. with a sampling interval allowing the resolution of all important timescales) in key places of the Mediterranean Sea (straits and channels, zones of dense water formation, deep parts of the basins), constitute a priority in the context of global changes. This led CIESM (The Mediterranean Science Commission) to support, since 2002, the HYDROCHANGES programme (http//www.ciesm.org/marine/programs/hydrochanges.htm), a network of autonomous conductivity, temperature, and depth (CTD) sensors, deployed on mainly short and easily manageable subsurface moorings, within the core of a certain water mass. The HYDROCHANGES strategy is twofold and develops on different scales. To get information about long-term changes of hydrological characteristics, long time series are needed. But before these series are long enough they allow the detection of links between them at shorter timescales that may provide extremely valuable information about the functioning of the Mediterranean Sea. The aim of this paper is to present the history of the programme and the current set-up of the network (monitored sites, involved groups) as well as to provide for the first time an overview of all the time series collected under the HYDROCHANGES umbrella, discussing the results obtained thanks to the programme.

scholarly journals The very first transformation of the Mediterranean outflow in the Strait of Gibraltar

2011 ◽  
Vol 116 (C7) ◽  
Author(s):  
Jesús García-Lafuente ◽  
Antonio Sánchez-Román ◽  
Cristina Naranjo ◽  
José C. Sánchez-Garrido
Keyword(s):  
Strait Of Gibraltar ◽  
Mediterranean Outflow ◽  
The Mediterranean

scholarly journals Mediterranean Sea climatic indices: monitoring long term variability and climate changes

2018 ◽  
Author(s):  
Athanasia Iona ◽  
Athanasios Theodorou ◽  
Sarantis Sofianos ◽  
Sylvain Watelet ◽  
Charles Troupin ◽  
...  
Keyword(s):  
Climate Change ◽  
Time Series ◽  
Mediterranean Sea ◽  
Climate Changes ◽  
Salt Content ◽  
Climatic Indices ◽  
In Situ Observations ◽  
The Mediterranean

Abstract. We present a new product composed of a set of thermohaline climatic indices from 1950 to 2015 for the Mediterranean Sea such as decadal temperature and salinity anomalies, their mean values over selected depths, decadal ocean heat and salt content anomalies at selected depth layers as well as their long times series. It is produced from a new high-resolution climatology of temperature and salinity on a 1/8° regular grid based on historical high quality in situ observations. Ocean heat and salt content differences between 1980–2015 and 1950–1979 are compared for evaluation of the climate shift in the Mediterranean Sea. The spatial patterns of heat and salt content shifts demonstrate in greater detail than ever before that the climate changes differently in the several regions of the basin. Long time series of heat and salt content for the period 1950 to 2015 are also provided which indicate that in the Mediterranean Sea there is a net mean volume warming and salting since 1950 with acceleration during the last two decades. The time series also show that the ocean heat content seems to fluctuate on a cycle of about 40 years and seems to follow the Atlantic Multidecadal Oscillation climate cycle indicating that the natural large scale atmospheric variability could be superimposed on to the warming trend. This product is an observations-based estimation of the Mediterranean climatic indices. It relies solely on spatially interpolated data produced from in-situ observations averaged over decades in order to smooth the decadal variability and reveal the long term trends with more accuracy. It can provide a valuable contribution to the modellers' community, next to the satellite-based products and serve as a baseline for the evaluation of climate-change model simulations contributing thus to a better understanding of the complex response of the Mediterranean Sea to the ongoing global climate change. The product is available here: https://doi.org/10.5281/zenodo.1210100.

scholarly journals Anthropogenic and natural CO<sub>2</sub> exchange through the Strait of Gibraltar

2009 ◽  
Vol 6 (4) ◽  
pp. 647-662 ◽  
Author(s):  
I. E. Huertas ◽  
A. F. Ríos ◽  
J. García-Lafuente ◽  
A. Makaoui ◽  
S. Rodríguez-Gálvez ◽  
...  
Keyword(s):  
Time Series ◽  
Atlantic Ocean ◽  
Mediterranean Sea ◽  
Mediterranean Basin ◽  
Inorganic Carbon ◽  
Strait Of Gibraltar ◽  
Anthropogenic Carbon ◽  
The Mediterranean ◽  
The Mediterranean Basin ◽  
Mediterranean Water

Abstract. The exchange of both anthropogenic and natural inorganic carbon between the Atlantic Ocean and the Mediterranean Sea through Strait of Gibraltar was studied for a period of two years under the frame of the CARBOOCEAN project. A comprehensive sampling program was conducted, which was design to collect samples at eight fixed stations located in the Strait in successive cruises periodically distributed through the year in order to ensure a good spatial and temporal coverage. As a result of this monitoring, a time series namely GIFT (GIbraltar Fixed Time series) has been established, allowing the generation of an extensive data set of the carbon system parameters in the area. Data acquired during the development of nine campaigns were analyzed in this work. Total inorganic carbon concentration (CT) was calculated from alkalinity-pHT pairs and appropriate thermodynamic relationships, with the concentration of anthropogenic carbon (CANT) being also computed using two methods, the ΔC* and the TrOCA approach. Applying a two-layer model of water mass exchange through the Strait and using a value of −0.85 Sv for the average transport of the outflowing Mediterranean water recorded in situ during the considered period, a net export of inorganic carbon from the Mediterranean Sea to the Atlantic was obtained, which amounted to 25±0.6 Tg C yr−1. A net alkalinity output of 16±0.6 Tg C yr−1 was also observed to occur through the Strait. In contrast, the Atlantic water was found to contain a higher concentration of anthropogenic carbon than the Mediterranean water, resulting in a net flux of CANT towards the Mediterranean basin of 4.20±0.04 Tg C yr−1 by using the ΔC* method, which constituted the most adequate approach for this environment. A carbon balance in the Mediterranean was assessed and fluxes through the Strait are discussed in relation to the highly diverse estimates available in the literature for the area and the different approaches considered for CANT estimation. This work unequivocally confirms the relevant role of the Strait of Gibraltar as a controlling point for the biogeochemical exchanges occurring between the Mediterranean Sea and the Atlantic Ocean and emphasizes the influence of the Mediterranean basin in the carbon inventories of the North Atlantic.

Habitat mapping and change assessment of coastal wetlands by using Sentinel-2 time series and ecological expert knowledge

2020 ◽  
Author(s):  
Maria Adamo ◽  
Valeria Tomaselli ◽  
Francesca Mantino ◽  
Cristina Tarantino ◽  
Palma Blonda
Keyword(s):  
Time Series ◽  
Land Cover ◽  
Coastal Wetlands ◽  
Expert Knowledge ◽  
Land Reclamation ◽  
Habitat Mapping ◽  
The Mediterranean ◽  
The Impact ◽  
Sentinel 2

&lt;p&gt;Coastal wetlands are one of the most threatened ecosystems worldwide. In the Mediterranean Region, wetlands are undergoing rapid changes due to the increasing of human pressures (e.g. land reclamation, water resources exploitation) and climate changes (e.g. coastal erosion), with a resulting habitat degradation, fragmentation, and biodiversity loss.&lt;/p&gt;&lt;p&gt;Long-term habitat mapping and change detection are essential for the management of coastal wetlands as well as for evaluating the impact of conservation policies.&lt;/p&gt;&lt;p&gt;Earth observation (EO) data and techniques are a valuable resource for long-term habitat mapping, thanks to the large amount of available data and their high spatial and temporal resolution. In this study, we propose an approach based on the integration of time series of Sentinel-2 images and ecological expert knowledge for land cover (LC) mapping and automatic translation to habitats in coastal wetlands. In particular, the research relies on the exploitation of ecological rules based on combined information related to plant phenology, water seasonality of aquatic species, pattern zonation, and habitat geometric properties.&lt;/p&gt;&lt;p&gt;The methodology is applied to two Natura2000 sites, &amp;#8220;Zone umide della Capitanata&amp;#8221; and &amp;#8220;Paludi presso il Golfo di Manfredonia&amp;#8221;, located in the northeastern part of the Puglia region. These two areas are the most extensive wetlands of the Italian peninsula and the largest components of the Mediterranean wetland system.&lt;/p&gt;&lt;p&gt;Land Cover classes are labelled according to the FAO-LCCS taxonomy, which offers a framework to integrate EO data with in situ and ancillary data. Output habitat classes are labelled according to EUNIS habitat classification.&lt;/p&gt;

scholarly journals Interannual variability of the Mediterranean outflow observed in Espartel sill, western Strait of Gibraltar

2009 ◽  
Vol 114 (C10) ◽  
Author(s):  
J. García-Lafuente ◽  
J. Delgado ◽  
A. Sánchez Román ◽  
J. Soto ◽  
L. Carracedo ◽  
...  
Keyword(s):  
Interannual Variability ◽  
Strait Of Gibraltar ◽  
Mediterranean Outflow ◽  
The Mediterranean
Sign in / Sign up

Export Citation Format

Share Document