- Autonomous underwater gliders have been used for over a decade to collect ocean data across all depths and regions. The Challenger Glider Mission aims to use gliders to explore five ocean basins over 128,000 km.
- Students will compare temperature, salinity, and current data collected by glider RU29 on its journey from Ascension Island to São Paulo, Brazil to predictions from the RTOFS and MyOcean ocean models. This will assess the accuracy of available global ocean models.
- Preliminary analysis found the MyOcean model differed from RU29's measurements by about 1°C on average, while discrepancies in the RTOFS model were less widespread but of greater magnitude.
Editorial - May 2014 - Special Issue jointly coordinated by Mercator Ocean and Coriolis
focusing on Ocean Observations
Greetings all,
Once a year and for the fi fth year in a raw, the Mercator Ocean Forecasting Center in Toulouse and the Coriolis Infrastructure in Brest publish a
common newsletter. Some papers are dedicated to observations only, when others display collaborations between the 2 aspects: Observations and
Modelling/Data assimilation.
The fi rst paper by Cabanes et al. introducing this issue is presenting a new methodology aiming at correcting Argo fl oat salinity measurements in
delayed time when Argo fl oats conductivity sensors are subject to drift and offset due to bio-fouling or other technical problems.
Then, Cravatte et al. are using the Argo arrays in order to compile Argo fl oats’ drifts and show that they are a very valuable tool allowing determining
the absolute velocity. They apply this to study zonal jets at 1000 meters depth in the Tropics.
In the next paper, Maes and O’Kane provide with some results indicating the impact of a sustained ocean observing Argo network on the ability to
resolve the seasonal cycle of salinity stratifi cation by contrasting periods pre- and post-Argo. They take into account the respective thermal and saline
dependencies in the Brunt-Väisälä frequency (N2) in order to isolate the specifi c role of the salinity stratifi cation in the layers above the main pycno-
cline.
Picheral et al. are telling us about the Tara Oceans voyage that took place on the schooner “Tara” from 2009 to 2013 and visited all oceans. The ship
was adapted for modern oceanography. Scientifi c instruments were mounted on a dedicated CTD frame and installed on an underway fl ow-through
system. Data were sent daily to Coriolis. Post cruise calibrations were performed leading to a high quality dataset.
Then, Roquet et al. demonstrate the importance of the contribution of hydrographic and biogeochemical data collected by Antarctic marine mammals,
and in particular elephant seals, equipped with a new generation of oceanographic tags, for the environmental monitoring of the Southern Ocean.
The last paper of the present issue is displaying the collaboration between the Ocean Observations and Ocean Modelling communities: Turpin et
al. perform several Observing System Experiments in order to assess the impact of Argo observations on the Mercator Océan global analysis and
forecasting system at ¼ degree resolution.
We wish you a pleasant reading,
Laurence Crosnier and Sylvie Pouliquen, Editors.
#50
Newsletter
QUARTERLY
The Tara Oceans voyage took place on the schooner “Tara” from 2009 to 2013 and visited all oceans to collect samples and data in order to study the relationships between ecosystem biodiversity and function and the physical-chemical oceanographic environ-
ment (water mass, transport) (cf Picheral et al. this issue).
Credits: Francois Aurat/Tara Expéditions; Marc Picheral/LOV
Greetings all,
Once a year in April, the Mercator Ocean Forecasting Center in Toulouse and the Coriolis Infrastructure in Brest publish a common newsletter. Papers are dedicated to observations only.
• The first paper introducing this issue is presenting the Coriolis 2014-2020 framework which was renewed in 2014 in order to go on integrating in-situ ocean observation infrastructure for operational oceanography and ocean/climate research.
• Next paper by Poffa et al. describes how some Argo floats are deployed by the sailing community, through ship-based non-governmental organization or trans-oceanic races. It allows Argo floats to be deployed in poorly sampled areas where there is no regular shipping. Sailors got also involved in oceanographic science activities. An example of float deployment is given in the case of the Barcelona World Race.
• Next paper by Pouliquen et al. describes the EURO-ARGO ERIC infrastructure which is now officially set-up since May 2014. The objective of the Euro-Argo ERIC is to organize a long term European contribution to the international Argo array of profiling floats.
• Le Traon et al. are then presenting how the assessment of the impact of ARGO in Ocean models and satellite validation is conducted in the context of E-AIMS (Euro-Argo improvements for the GMES/Copernicus Marine Service) FP7 project. Observing System Evaluations and Observing System Simulation Experiments have been conducted to quantify the contribution of Argo to constrain global and regional monitoring and forecasting centers and validate satellite observations. Recommendations for the new phase of Argo are also elaborated.
• Kolodziejczyk et al. follow with the presentation of the complementarity of ARGO and SMOS Sea Surface Salinity (SSS) observations to help monitoring SSS variability from basin to meso scale. Using a 4-year time-series of SMOS SSS data and the global Argo array of in situ measurements, a statistical approach and an optimal interpolation method are used to characterize biases and reduce noises. Results are promising and show strong complementarity between SMOS and Argo data.
• Herbert et al. then describe Shipboard Acoustic Doppler Current Profilers (SADCP) observations which are carried out in the Tropical Atlantic during yearly cruises in the framework of the PIRATA program. The present note displays the SADCP data processing methodology applied for 8 PIRATA cruises by using CASCADE software.
• Cravatte et al. follow with a paper presenting the new international TPOS2020 project (2014-2020). The project objective is to build a renewed, integrated, internationally-coordinated and sustainable observing system in the Tropical Pacific, meeting both the needs of climate research and operational forecasting systems and learning lessons from the great success-and finally partial collapse- of the TAO/TRITON array.
• Saout-Grit et al. next present an updated procedure for CTD-oxygen calibration along with new
Assessing the ability of SWAT as a water quality model in the Lake Victoria b...Timo Brussée
There is a need for a water quality model for use in the Lake Victoria basin countries in East-Africa. The
region is characterised by data scarcity, a tropical climate and riverine, lacustrine tidal wetlands which form
an important buffer to riverine pollution of the lake. These characteristics of the basin form a challenge for
water quality models. The objective is to state the strengths and weaknesses of a potential water quality
model under these challenging conditions. This objective is executed with the soil water assessment tool
(SWAT) in a catchment of the Lake Victoria Basin as pilot area. The pilot area of the Mara river basin is
hydrologically complex containing tropical and plantation forest, savanna, grasslands, bi-annual agriculture,
shrublands and wetlands. It has varied soil types and bi-annual rain seasons
The study consist of literature research and flow simulation of the transboundary Mara river basin. The
model study aims to characterise the hydrology in the pilot area. The study includes a thorough analysis of
rainfall, stage and flow data. Model preparation steps include the use of weighted-area rainfall estimation
methods, climate model data and empirical derivation of soil input parameters. Discharge calibration
methods include multi-site calibration, by making use of an alternative objective function statistic for the
commonly used Nash-Sutcliffe Efficiency (NSE) called the Kling-Gupta Efficiency (KGE). The literature study
targets previous flow and water quality studies done in tropical or wetland areas, thereby looking to see how
these studies adapted to hydrological modelling with SWAT in tropical or wetland areas, and why theses
adaptions were made. The literature research also includes a comparison of wetland processes in SWAT
with the physical, biological and chemical processes as described in previous studies.
The Mara river basin flow simulation gave a satisfactory model performance for two out of three calibration
sites, thereby being able to give preliminary outputs on water-balance and other flow characteristics. During
research, a number of model, knowledge and data gaps were found to be critical for better understanding
the hydrological and water quality system workings in the Lake Victoria and Mara river basin. From the
model and literature study it is concluded that several issues on data scarcity and hydrological model
processes in the tropics can be overcome. These do not necessarily decrease model performance or
uncertainty in the SWAT model. However, wetland processes are oversimplified in SWAT. Modification and
coupled SWAT models yet have not been able to provide an alternative to the default model that adequately
represents the main flow, sediment and nutrients processes and fluxes that are present in Mara’s wetlands.
Editorial - May 2014 - Special Issue jointly coordinated by Mercator Ocean and Coriolis
focusing on Ocean Observations
Greetings all,
Once a year and for the fi fth year in a raw, the Mercator Ocean Forecasting Center in Toulouse and the Coriolis Infrastructure in Brest publish a
common newsletter. Some papers are dedicated to observations only, when others display collaborations between the 2 aspects: Observations and
Modelling/Data assimilation.
The fi rst paper by Cabanes et al. introducing this issue is presenting a new methodology aiming at correcting Argo fl oat salinity measurements in
delayed time when Argo fl oats conductivity sensors are subject to drift and offset due to bio-fouling or other technical problems.
Then, Cravatte et al. are using the Argo arrays in order to compile Argo fl oats’ drifts and show that they are a very valuable tool allowing determining
the absolute velocity. They apply this to study zonal jets at 1000 meters depth in the Tropics.
In the next paper, Maes and O’Kane provide with some results indicating the impact of a sustained ocean observing Argo network on the ability to
resolve the seasonal cycle of salinity stratifi cation by contrasting periods pre- and post-Argo. They take into account the respective thermal and saline
dependencies in the Brunt-Väisälä frequency (N2) in order to isolate the specifi c role of the salinity stratifi cation in the layers above the main pycno-
cline.
Picheral et al. are telling us about the Tara Oceans voyage that took place on the schooner “Tara” from 2009 to 2013 and visited all oceans. The ship
was adapted for modern oceanography. Scientifi c instruments were mounted on a dedicated CTD frame and installed on an underway fl ow-through
system. Data were sent daily to Coriolis. Post cruise calibrations were performed leading to a high quality dataset.
Then, Roquet et al. demonstrate the importance of the contribution of hydrographic and biogeochemical data collected by Antarctic marine mammals,
and in particular elephant seals, equipped with a new generation of oceanographic tags, for the environmental monitoring of the Southern Ocean.
The last paper of the present issue is displaying the collaboration between the Ocean Observations and Ocean Modelling communities: Turpin et
al. perform several Observing System Experiments in order to assess the impact of Argo observations on the Mercator Océan global analysis and
forecasting system at ¼ degree resolution.
We wish you a pleasant reading,
Laurence Crosnier and Sylvie Pouliquen, Editors.
#50
Newsletter
QUARTERLY
The Tara Oceans voyage took place on the schooner “Tara” from 2009 to 2013 and visited all oceans to collect samples and data in order to study the relationships between ecosystem biodiversity and function and the physical-chemical oceanographic environ-
ment (water mass, transport) (cf Picheral et al. this issue).
Credits: Francois Aurat/Tara Expéditions; Marc Picheral/LOV
Greetings all,
Once a year in April, the Mercator Ocean Forecasting Center in Toulouse and the Coriolis Infrastructure in Brest publish a common newsletter. Papers are dedicated to observations only.
• The first paper introducing this issue is presenting the Coriolis 2014-2020 framework which was renewed in 2014 in order to go on integrating in-situ ocean observation infrastructure for operational oceanography and ocean/climate research.
• Next paper by Poffa et al. describes how some Argo floats are deployed by the sailing community, through ship-based non-governmental organization or trans-oceanic races. It allows Argo floats to be deployed in poorly sampled areas where there is no regular shipping. Sailors got also involved in oceanographic science activities. An example of float deployment is given in the case of the Barcelona World Race.
• Next paper by Pouliquen et al. describes the EURO-ARGO ERIC infrastructure which is now officially set-up since May 2014. The objective of the Euro-Argo ERIC is to organize a long term European contribution to the international Argo array of profiling floats.
• Le Traon et al. are then presenting how the assessment of the impact of ARGO in Ocean models and satellite validation is conducted in the context of E-AIMS (Euro-Argo improvements for the GMES/Copernicus Marine Service) FP7 project. Observing System Evaluations and Observing System Simulation Experiments have been conducted to quantify the contribution of Argo to constrain global and regional monitoring and forecasting centers and validate satellite observations. Recommendations for the new phase of Argo are also elaborated.
• Kolodziejczyk et al. follow with the presentation of the complementarity of ARGO and SMOS Sea Surface Salinity (SSS) observations to help monitoring SSS variability from basin to meso scale. Using a 4-year time-series of SMOS SSS data and the global Argo array of in situ measurements, a statistical approach and an optimal interpolation method are used to characterize biases and reduce noises. Results are promising and show strong complementarity between SMOS and Argo data.
• Herbert et al. then describe Shipboard Acoustic Doppler Current Profilers (SADCP) observations which are carried out in the Tropical Atlantic during yearly cruises in the framework of the PIRATA program. The present note displays the SADCP data processing methodology applied for 8 PIRATA cruises by using CASCADE software.
• Cravatte et al. follow with a paper presenting the new international TPOS2020 project (2014-2020). The project objective is to build a renewed, integrated, internationally-coordinated and sustainable observing system in the Tropical Pacific, meeting both the needs of climate research and operational forecasting systems and learning lessons from the great success-and finally partial collapse- of the TAO/TRITON array.
• Saout-Grit et al. next present an updated procedure for CTD-oxygen calibration along with new
Assessing the ability of SWAT as a water quality model in the Lake Victoria b...Timo Brussée
There is a need for a water quality model for use in the Lake Victoria basin countries in East-Africa. The
region is characterised by data scarcity, a tropical climate and riverine, lacustrine tidal wetlands which form
an important buffer to riverine pollution of the lake. These characteristics of the basin form a challenge for
water quality models. The objective is to state the strengths and weaknesses of a potential water quality
model under these challenging conditions. This objective is executed with the soil water assessment tool
(SWAT) in a catchment of the Lake Victoria Basin as pilot area. The pilot area of the Mara river basin is
hydrologically complex containing tropical and plantation forest, savanna, grasslands, bi-annual agriculture,
shrublands and wetlands. It has varied soil types and bi-annual rain seasons
The study consist of literature research and flow simulation of the transboundary Mara river basin. The
model study aims to characterise the hydrology in the pilot area. The study includes a thorough analysis of
rainfall, stage and flow data. Model preparation steps include the use of weighted-area rainfall estimation
methods, climate model data and empirical derivation of soil input parameters. Discharge calibration
methods include multi-site calibration, by making use of an alternative objective function statistic for the
commonly used Nash-Sutcliffe Efficiency (NSE) called the Kling-Gupta Efficiency (KGE). The literature study
targets previous flow and water quality studies done in tropical or wetland areas, thereby looking to see how
these studies adapted to hydrological modelling with SWAT in tropical or wetland areas, and why theses
adaptions were made. The literature research also includes a comparison of wetland processes in SWAT
with the physical, biological and chemical processes as described in previous studies.
The Mara river basin flow simulation gave a satisfactory model performance for two out of three calibration
sites, thereby being able to give preliminary outputs on water-balance and other flow characteristics. During
research, a number of model, knowledge and data gaps were found to be critical for better understanding
the hydrological and water quality system workings in the Lake Victoria and Mara river basin. From the
model and literature study it is concluded that several issues on data scarcity and hydrological model
processes in the tropics can be overcome. These do not necessarily decrease model performance or
uncertainty in the SWAT model. However, wetland processes are oversimplified in SWAT. Modification and
coupled SWAT models yet have not been able to provide an alternative to the default model that adequately
represents the main flow, sediment and nutrients processes and fluxes that are present in Mara’s wetlands.
Editorial – October 2011 – Three of the MyOcean long time series reanalysis products
Greengs all,
This month’s newsleer is devoted to three of the MyOcean long me series Reanalysis products: the In Situ temperature and salinity CORA reanalysis
(1990 to 2010), the reanalysis of the North Atlanc ocean biogeochemistry (1998-2007) and the Arcc Ocean sea-ice dri/ reanalysis (1992-
2010).
The first product described here is the In Situ temperature and salinity CORA reanalysis (1990 to 2010). A new version of the comprehensive and
qualified ocean in-situ dataset (the Coriolis dataset for Re-Analysis - CORA) is released for the period 1990 to 2010. This in-situ dataset of temperature
and salinity profiles, from different data types (Argo, GTS data, VOS ships, NODC historical data...) on the global scale, is meant to be used for
general oceanographic research purposes, for ocean model validaon, and also for inializaon or assimilaon of ocean models. This product is
available from the MyOcean web portal (hp://www.myocean.eu/).
The second product is the reanalysis of the North Atlanc ocean biogeochemistry (1998-2007). A system assimilang Ocean Colour SeaWiFS data
during the period 1998-2007 has been designed to construct a reanalysis of the North Atlanc ocean biogeochemistry based on a coupled physicalbiogeochemical
model at eddy-admi:ng resoluon. The aim of this study is, on the one hand to develop the skeleton of a pre-operaonal coupled
physical-biogeochemical system with real-me assimilave/forecasng capability, and on the other hand to operate this prototype system for producing
a biogeochemical reanalysis covering the 1998-2007 period. This product is not available from the MyOcean web portal yet.
The third reanalysis product is the 1992-2010 winter Arcc Ocean sea ice dri/ me series made at Ifremer/CERSAT from satellite measurements
which consists of several products: the Level 3 products from single sensors and the L4 products from the combinaon of sensors. They are available
at 3, 6 and 30 day-lag with a 62.5 km-grid size during winter. This dataset is available for oceanic and climate modelling as well as various scienfic
studies in the Arcc. The me series is ongoing and will connue for Arcc long term monitoring using the next MetOp/ASCAT operaonal
scaerometers, planned to be operated for the next 10 years. This product is available from the MyOcean web portal (hp://www.myocean.eu/).
The next January 2012 issue will be dedicated to various applicaons using the Mercator Ocean products.
We wish you a pleasant reading!
Application of GIS and MODFLOW to Ground Water Hydrology- A ReviewIJERA Editor
Groundwater is one of the most valuable natural resources, which supports human health, economic
development and ecological diversity. Due to over exploitation, the ground water systems are affected and
require management to maintain the conditions of ground water resources within acceptable limits. With the
development of computers and advances in information technology, efficient techniques for water management
has evolved. The main intent of the paper is to present a comprehensive review on application of GIS
(Geographic Information System) followed by coupling with MODFLOW package for ground water
management and development. Two major areas are discussed stating GIS applications in ground water
hydrology. (i) GIS based subsurface flow and pollution modelling (ii) Selection of artificial recharge sites.
Although the use of these techniques in groundwater studies has rapidly increased since last decade the sucess
rate is very limited. Based on this review , it is concluded that integation of GIS and MODFLOW have great
potential to revolutionize the monitoring and management of vital ground water resources in the future.
Modeling Sediment Accumulation at Kenyir Reservoir Using GSTARS3ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Greetings all,
This month’s newsletter is devoted to data assimilation and its application to Ocean Reanalyses.
Brasseur is introducing this newsletter telling us about the history of Ocean Reanalyses, the need for such Reanalyses for
MyOcean users in particular, and the perspective of Ocean Reanalyses coupled with biogeochemistry or regional systems for
example.
Scientific articles about Ocean Reanalyses activities are then displayed as follows: First, Cabanes et al. are presenting CORA, a
new comprehensive and qualified ocean in-situ dataset from 1990 to 2008, developped at the Coriolis Data Centre at IFREMER
and used to build Ocean Reanalyses. A more comprehensive article will be devoted to the CORA dataset in our next April 2010
issue. Then, Remy at Mercator in Toulouse considers large scale decadal Ocean Reanalysis to assess the improvement due to
the variational method data assimilation and show the sensitivity of the estimate to different parameters. She uses a light
configuration system allowing running several long term reanalysis. Third, Ferry et al. present the French Global Ocean
Reanalysis (GLORYS) project which aims at producing eddy resolving global Ocean Reanalyses with different streams spanning different time periods and using different technical choices. This is a collaboration between Mercator and French research
laboratories, and is a contribution to the European MyOcean project. Then, Masina et al. at CMCC in Italy are presenting the
implementation of data assimilation techniques into global ocean circulation model in order to investigate the role of the ocean on
climate variability and predictability. Fifth, Smith et al. are presenting the Ocean Reanalyses studies at ESSC in the U.K. which
aim at reconstructing water masses variability and ocean transports. Finally, Langlais et al. are giving an example of the various
uses of ocean reanalyses: they are using the Australian BlueLink Reanalysis in order to look into details at the various Southern
Ocean fronts.
The next April 2010 newsletter will introduce a new editorial line with a common newsletter between the Mercator
Ocean Forecasting Center in Toulouse and the Coriolis Data Center at Ifremer in Brest. Some papers will be
dedicated to observations only, when others will display collaborations between the 2 aspects: Observations and
Model. The idea is to wider and complete the subjects treated in our newsletter, as well as to trigger interactions
between observations and modeling communities. This common Mercator-Coriolis Newsletter is a test for which
we will take the opportunity to ask for your feedback.
We wish you a pleasant reading!
A convection decay model for simulating the transmission of flood waves in ep...Amro Elfeki
Elfeki, A.M.M., Hatem A Ewea, Jarbou A Bahrawi, Nassir S Al-Amri: A Convection-Decay Model for Simulating the Transmission of Flood Waves in Ephemeral Channels in Arid Zones (2014). 6 International Conference on Water Resources and th Arid Environments (ICWRAE 6): 328-333, 16-17 December, 2014, Riyadh, Saudi Arabia.
Greetings all,
This month’s newsletter is devoted to Data Assimilation and its techniques and progress for operational oceanography.
Gary Brassington is first introducing this newsletter with a paper telling us about the international summer school for “observing,
assimilating and forecasting the ocean” which will be held in Perth, Western Australia in 11-22 January 2010
(http://www.bom.gov.au/bluelink/summerschool/). The course curriculum will include topics covering the leading edge science in
ocean observing systems, as well as the latest methods and techniques for analysis, data assimilation and ocean modeling.
Scientific articles about Data Assimilation are then displayed as follows: The first article by Broquet et al. is dealing with Ocean
state and surface forcing correction using the ROMS-IS4DVAR Data Assimilation System. Then, Cosme et al. are describing the
SEEK smoother as a Data Assimilation scheme for oceanic reanalyses. The next article by Brankart et al. is displaying a synthetic
literature review on the following subject: Is there a simple way of controlling the forcing function of the Ocean? Then Ferry et al.
are telling us about Ocean-Atmosphere flux correction by Ocean Data Assimilation. The last article by Oke et al. is dealing with
Data Assimilation in the Australian BlueLink System.
The next October 2009 newsletter will review the current work on ocean biology and biogeochemistry.
We wish you a pleasant reading!
Effects of antifouling technology application on Marine ecological environment
Thermocline Model for Estimating Argo Sea Surface Temperature
Applications of Peridynamics in Marine Structures
Thermal and Structural Behaviour of Offshore Structures with Passive Fire Protection
Functionally graded material and its application to marine structures
Editorial – October 2011 – Three of the MyOcean long time series reanalysis products
Greengs all,
This month’s newsleer is devoted to three of the MyOcean long me series Reanalysis products: the In Situ temperature and salinity CORA reanalysis
(1990 to 2010), the reanalysis of the North Atlanc ocean biogeochemistry (1998-2007) and the Arcc Ocean sea-ice dri/ reanalysis (1992-
2010).
The first product described here is the In Situ temperature and salinity CORA reanalysis (1990 to 2010). A new version of the comprehensive and
qualified ocean in-situ dataset (the Coriolis dataset for Re-Analysis - CORA) is released for the period 1990 to 2010. This in-situ dataset of temperature
and salinity profiles, from different data types (Argo, GTS data, VOS ships, NODC historical data...) on the global scale, is meant to be used for
general oceanographic research purposes, for ocean model validaon, and also for inializaon or assimilaon of ocean models. This product is
available from the MyOcean web portal (hp://www.myocean.eu/).
The second product is the reanalysis of the North Atlanc ocean biogeochemistry (1998-2007). A system assimilang Ocean Colour SeaWiFS data
during the period 1998-2007 has been designed to construct a reanalysis of the North Atlanc ocean biogeochemistry based on a coupled physicalbiogeochemical
model at eddy-admi:ng resoluon. The aim of this study is, on the one hand to develop the skeleton of a pre-operaonal coupled
physical-biogeochemical system with real-me assimilave/forecasng capability, and on the other hand to operate this prototype system for producing
a biogeochemical reanalysis covering the 1998-2007 period. This product is not available from the MyOcean web portal yet.
The third reanalysis product is the 1992-2010 winter Arcc Ocean sea ice dri/ me series made at Ifremer/CERSAT from satellite measurements
which consists of several products: the Level 3 products from single sensors and the L4 products from the combinaon of sensors. They are available
at 3, 6 and 30 day-lag with a 62.5 km-grid size during winter. This dataset is available for oceanic and climate modelling as well as various scienfic
studies in the Arcc. The me series is ongoing and will connue for Arcc long term monitoring using the next MetOp/ASCAT operaonal
scaerometers, planned to be operated for the next 10 years. This product is available from the MyOcean web portal (hp://www.myocean.eu/).
The next January 2012 issue will be dedicated to various applicaons using the Mercator Ocean products.
We wish you a pleasant reading!
Application of GIS and MODFLOW to Ground Water Hydrology- A ReviewIJERA Editor
Groundwater is one of the most valuable natural resources, which supports human health, economic
development and ecological diversity. Due to over exploitation, the ground water systems are affected and
require management to maintain the conditions of ground water resources within acceptable limits. With the
development of computers and advances in information technology, efficient techniques for water management
has evolved. The main intent of the paper is to present a comprehensive review on application of GIS
(Geographic Information System) followed by coupling with MODFLOW package for ground water
management and development. Two major areas are discussed stating GIS applications in ground water
hydrology. (i) GIS based subsurface flow and pollution modelling (ii) Selection of artificial recharge sites.
Although the use of these techniques in groundwater studies has rapidly increased since last decade the sucess
rate is very limited. Based on this review , it is concluded that integation of GIS and MODFLOW have great
potential to revolutionize the monitoring and management of vital ground water resources in the future.
Modeling Sediment Accumulation at Kenyir Reservoir Using GSTARS3ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Greetings all,
This month’s newsletter is devoted to data assimilation and its application to Ocean Reanalyses.
Brasseur is introducing this newsletter telling us about the history of Ocean Reanalyses, the need for such Reanalyses for
MyOcean users in particular, and the perspective of Ocean Reanalyses coupled with biogeochemistry or regional systems for
example.
Scientific articles about Ocean Reanalyses activities are then displayed as follows: First, Cabanes et al. are presenting CORA, a
new comprehensive and qualified ocean in-situ dataset from 1990 to 2008, developped at the Coriolis Data Centre at IFREMER
and used to build Ocean Reanalyses. A more comprehensive article will be devoted to the CORA dataset in our next April 2010
issue. Then, Remy at Mercator in Toulouse considers large scale decadal Ocean Reanalysis to assess the improvement due to
the variational method data assimilation and show the sensitivity of the estimate to different parameters. She uses a light
configuration system allowing running several long term reanalysis. Third, Ferry et al. present the French Global Ocean
Reanalysis (GLORYS) project which aims at producing eddy resolving global Ocean Reanalyses with different streams spanning different time periods and using different technical choices. This is a collaboration between Mercator and French research
laboratories, and is a contribution to the European MyOcean project. Then, Masina et al. at CMCC in Italy are presenting the
implementation of data assimilation techniques into global ocean circulation model in order to investigate the role of the ocean on
climate variability and predictability. Fifth, Smith et al. are presenting the Ocean Reanalyses studies at ESSC in the U.K. which
aim at reconstructing water masses variability and ocean transports. Finally, Langlais et al. are giving an example of the various
uses of ocean reanalyses: they are using the Australian BlueLink Reanalysis in order to look into details at the various Southern
Ocean fronts.
The next April 2010 newsletter will introduce a new editorial line with a common newsletter between the Mercator
Ocean Forecasting Center in Toulouse and the Coriolis Data Center at Ifremer in Brest. Some papers will be
dedicated to observations only, when others will display collaborations between the 2 aspects: Observations and
Model. The idea is to wider and complete the subjects treated in our newsletter, as well as to trigger interactions
between observations and modeling communities. This common Mercator-Coriolis Newsletter is a test for which
we will take the opportunity to ask for your feedback.
We wish you a pleasant reading!
A convection decay model for simulating the transmission of flood waves in ep...Amro Elfeki
Elfeki, A.M.M., Hatem A Ewea, Jarbou A Bahrawi, Nassir S Al-Amri: A Convection-Decay Model for Simulating the Transmission of Flood Waves in Ephemeral Channels in Arid Zones (2014). 6 International Conference on Water Resources and th Arid Environments (ICWRAE 6): 328-333, 16-17 December, 2014, Riyadh, Saudi Arabia.
Greetings all,
This month’s newsletter is devoted to Data Assimilation and its techniques and progress for operational oceanography.
Gary Brassington is first introducing this newsletter with a paper telling us about the international summer school for “observing,
assimilating and forecasting the ocean” which will be held in Perth, Western Australia in 11-22 January 2010
(http://www.bom.gov.au/bluelink/summerschool/). The course curriculum will include topics covering the leading edge science in
ocean observing systems, as well as the latest methods and techniques for analysis, data assimilation and ocean modeling.
Scientific articles about Data Assimilation are then displayed as follows: The first article by Broquet et al. is dealing with Ocean
state and surface forcing correction using the ROMS-IS4DVAR Data Assimilation System. Then, Cosme et al. are describing the
SEEK smoother as a Data Assimilation scheme for oceanic reanalyses. The next article by Brankart et al. is displaying a synthetic
literature review on the following subject: Is there a simple way of controlling the forcing function of the Ocean? Then Ferry et al.
are telling us about Ocean-Atmosphere flux correction by Ocean Data Assimilation. The last article by Oke et al. is dealing with
Data Assimilation in the Australian BlueLink System.
The next October 2009 newsletter will review the current work on ocean biology and biogeochemistry.
We wish you a pleasant reading!
Effects of antifouling technology application on Marine ecological environment
Thermocline Model for Estimating Argo Sea Surface Temperature
Applications of Peridynamics in Marine Structures
Thermal and Structural Behaviour of Offshore Structures with Passive Fire Protection
Functionally graded material and its application to marine structures
Describe and explain satellite remote sensing mission for monitoring.pdfalshaikhkhanzariarts
Describe and explain satellite remote sensing mission for monitoring water, carbon and global
climate change.
Solution
In recent years, the subjects of water, carbon, and global climate change
have attracted worldwide attention by scientists and the media. Climate
change, whether associated with human- induced or natural
variations, has and will continue to be important to policy makers and the
public. It is clear from reports such as that by the Intergovernmental Panelon Climate Change
(IPCC) [1] that
Earth observations play a critical role in providing information for assessment
and modeling. Improving these observations, better quality and newvariables, is a goal of most
national
and intergovernmental space agencies. Major initiatives are under waythat will result in benefits
to a broad
range of our global society. In the United States, a decadal study [2] was recently completed by
the
Committee on Earth Science and Applications of the US National Research
Council. The committee called for a commitment from the U.S. administration
to Earth observations to secure benefits for mankind. The report gives both
direction and a large boost to U.S. satellite programs as it recommended NOAA
to restore key observational capabilities of satellite missions and also that NASA
and NOAA launch 17 new satellite missions in the next 10 years. The study also
adds an additional focus to these missions: societal benefits.
Other countries have also been expanding their Earth observation programs
with numerous advanced concept satellite missions. Of particular relevance to
this issue are articles describing the
Earth observing programs of the
European Space Agency (ESA),
the Japanese Aerospace Exploration
Agency (JAXA), the China National
Space Administration (CNSA), the
Canadian Space Agency (CSA), and
the National Space Program Office
(NSPO) of Taiwan.
The ESA has a long history of
Earth observation from space that
began with meteorological missions
and has included a series of increasingly
sophisticated radars that have
provided valuable data about climate
and the changing environment. The
ESA’s current and future Earth observing
is under its Living Planet
Programme and includes the Earth
Explorer, meteorological, and Sentinel
missions.
JAXA has supported a wide range
of satellite-based instruments and
platforms that have and will provide
global Earth observations for water,
carbon, and climate. Of particular
note for the future is the commitment
to the Global Change Observation
Mission (GCOM) that will launch a
series of two types of satellites (water
and climate) to provide consistent and
continuous observations of key variables
over a 15-year period.
In addition to the United States,
ESA, and JAXA programs, there are
strong satellite-based Earth observing
programs in Canada, China, Argentina,
Taiwan, and Brazil.
In this Special Issue some of the
most significant recent and future Earth
observing satellites planned to monitor
water, carbon and global clima.
Greetings all,
This month’s newsletter is devoted to ocean indices aiming at a better understanding of the state of the ocean climate. Ocean
climate indices can be linked to major patterns of climate variability and usually have a significant social impact. The estimation of
the ocean climate indices along with their uncertainty is thus crucial: It gives an indication of our ability to measure the ocean. It is
as well a useful tool for decision making. Ocean climate indices also provide an at-a-glance overview of the state of the ocean
climate, and a way to talk to a wider audience about the ocean observing system. Several groups of experts are now working on
various ocean indicators using ocean forecast models, satellite data and reanalysis models in observing system simulation
experiments, among which the OOPC, NOAA and MERSEA/Boss4Gmes communities for example:
http://ioc3.unesco.org/oopc/state_of_the_ocean/index.php
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/
http://www.aoml.noaa.gov/phod/cyclone/data/method.html
http://www.mersea.eu.org/Indicators-with-B4G.html
Scientific articles about Ocean indices in the present Newsletter are displayed as follows: The first article by Von Schuckmann et
al. is dealing with the estimation of global ocean indicators from a gridded hydrographic field. Then, Crosnier et al. are describing
the need to conduct intercomparison of model analyses and forecast in order for experts to provide a reliable scientific expertise
on ocean climate indicators. The next article by Coppini et al. is telling us about ocean indices computed from the Mediterranean
Forecasting System for the European Environment Agency and Boss4Gmes. Then Buarque et al. are revisiting the Tropical
Cyclone Heat Potential Index in order to better represent the ocean heat content that interacts with Hurricane. The last article by Greiner et al. is dealing with the assessment of robust ocean indicators and gives an example with oceanic predictors for the
Sahel precipitations.
The next July 2009 newsletter will review the current work on data assimilation and its techniques and progress for operational
oceanography.
We wish you a pleasant reading.
PROBING FOR EVIDENCE OF PLUMES ON EUROPA WITH HST/STISSérgio Sacani
Roth et al. (2014a) reported evidence for plumes of water venting from a southern high latitude
region on Europa – spectroscopic detection of off-limb line emission from the dissociation
products of water. Here, we present Hubble Space Telescope (HST) direct images of Europa in
the far ultraviolet (FUV) as it transited the smooth face of Jupiter, in order to measure absorption
from gas or aerosols beyond the Europa limb. Out of ten observations we found three in which
plume activity could be implicated. Two show statistically significant features at latitudes similar
to Roth et al., and the third, at a more equatorial location. We consider potential systematic
effects that might influence the statistical analysis and create artifacts, and are unable to find any
that can definitively explain the features, although there are reasons to be cautious. If the
apparent absorption features are real, the magnitude of implied outgassing is similar to that of the
Roth et al. feature, however the apparent activity appears more frequently in our data.
Editorial – July 2011 – The latest space mission : SMOS, GOCE and CRYOSAT
Greengs all,
This month’s newsleer is devoted to the latest space mission and their use in physical oceasnography. A focus is here put on the possible physical oceanography
applicaons of the SMOS, GOCE and CRYOSAT missions.
SMOS (Soil Moisture and Ocean Salinity), launched on November 2, 2009, is the first satellite mission addressing sea surface salinity measurements from space. Realis-
c salinity maps have been obtained and preliminary validaon tests against in situ data indicate that the SMOS team is approaching its goals. SMOS will be a milestone
in the route for incorporang salinity to operaonal remote sensing.
The GOCE (Gravity Field and Steady-State Ocean Circulaon) satellite, first core Earth Explorer mission from ESA’s Living Planet programme, was successfully launched
on March, 17th 2009. One primary objecve of the GOCE mission is to determine the Earth geoid with an accuracy of 1-2 cm for a spaal resoluon of 100 km. This is
an important supplementary step towards the beer esmaon of the ocean Mean Dynamic Topography, a key reference surface for the assimilaon of almetric Sea
Level Anomalies into operaonal ocean forecasng systems.
ESA's CRYOSAT Earth Explorer mission was launched on 8 April 2010. Although its first mission is to provide the first satellite maps of sea-ice thickness, the CRYOSAT
mission is also operang over ocean surfaces providing a new source of valuable almeter measurements. It represents an addional almeter ocean mission complementary
to exisng Envisat, Jason-1 and Jason-2 missions in the operaonal mulmission processing chain of the SSALTO/DUACS system used in MyOcean.
The newsleer is presenng the following scienfic arcles: First, Font et al. present the characteriscs of the SMOS instrument, a summary of the sea surface salinity
retrieval from SMOS observaons and shows inial results obtained one year and a half a>er launch. At present there are sll several issues being addressed by the
SMOS team, mainly related to low level data processing but also to the retrieval of salinity from radiometric measurements, which prevent by now from reaching the
mission objecves in terms of salinity accuracy. However, realisc salinity maps have been obtained and will be presented. Second, Rio and Mulet carry out an independent
validaon of the different GOCE geoid models, in order to assess their accuracy and determine which one is beer suited for oceanographic applicaons and
Mean Dynamic Topography esmaon. Both the impact of the different methodologies used to compute the gravity fields as well as the contribuon of the four
months of supplementary data have been checked. Third, Dorendeu et al. present a dedicated experiment in order to esmate to which extent valuable ocean al-
metric signals can be extracted from CRYOSAT data and how this opportunity mission could be merged with exisng Envi
Remote sensing data driven bathing water quality assessment using sentinel-3nooriasukmaningtyas
In this paper we are investigating the possibility of usage of remote sensing satellite data, more precisely sentinel-3 OLCI and SLSTR data, for assessment of bathing water quality. In this research we used data driven approach and analysis of data in order to pinpoint aspects of remote sensing data that can be useful for bathing water quality assessment. For this purpose we collected satellite images for period from start of June till end of September of 2019 and results of in-situ measurement for the same period . Results of in-situ measurement were correlated with satellite images bands and analyzed. We propose a simple method for rapid assessment of possible deterioration of bathing water quality to be used by public health authorities for better planning of in situ measurements. Results of implementation of predictive models based on k-nearest neighbour (KNN) and decision tree (DT) are described.
A five-year National Science Foundation-funded Research Coordination Network (RCN), the “OceanObs” RCN, is currently in its third year. The RCN, through a series of working groups continues to focus on key issues in ocean observations. Two outcomes are highlighted in this presentation. Recommendations for improvements in the joint use of in situ and remote sensing were developed by one of the RCN’s working groups; an exemplar use case considered observation of coastal waters. An RCN supported working group examined the maturity of sensors for ocean biology observations. This presentation reviews the outcomes of these working groups.
1. Ocean Predictive Skill
Assessments in the South Atlantic:
Crowd-Sourcing of Student-Based Discovery
Rachael Sacatelli, Tobias Schofield, Katherine
Todoroff, Angela Carandang*, Alyson Eng*,
Ian Lowry*, Harrison Mather*, Antonio
Ramos**, Sebastiaan Swart***, Marcelo
Dottori****, Nilsen Strandskov, Josh Kohut,
Oscar Schofield and Scott Glenn
Rutgers University
Coastal Ocean Observation Lab
New Brunswick, NJ, USA
*United States Naval Academy
Annapolis, MD, USA
**Universidad de Las Palmas de Gran Canaria
Las Palmas, Gran Canaria
***Southern Ocean Carbon & Climate
Observatory, Council for Scientific and
Industrial Research, Stellenbosch, South Africa
and
Department of Oceanography, Marine Research
Institute, University of Cape Town,
Rondebosch, South Africa
****University of São Paulo,
Oceanographic Institute
São Paulo, Brazil
Abstract— Autonomous Underwater Gliders have over a
decade long history of successful regional deployments
serving scientific, societal and security needs in application
areas ranging from pole to pole and including the full range of
water depths from shallow coastal seas to the deep ocean.
Glider deployments covering the basin scale are much fewer,
but are a growing capacity as demonstrated by the Woods
Hole to Bermuda line that crosses the Gulf Stream, the
Atlantic Crossing line that follows the Gulf Stream, and the
basin circling flights now being conducted as part of the
Challenger Glider Mission.
The next step in the evolution of the global Challenger
mission is to enable an ensemble of modelers from different
institutions and agencies to participate in a meaningful way.
This process with be formalized in 2014 by leveraging the
data management tools of the U.S. Integrated Ocean
Observing System (IOOS) and the education tools of the U.S.
National Science Foundation’s (NSF) Ocean Observing
Initiative (OOI). The Education Visualization (EV) tools
developed by the OOI’s Education and Public Engagement
(EPE) Implementing Organization (IO) are currently being
configured through the cyber OOI net to display real time OOI
glider data with intuitive interactive browser-based tools,
reducing the barriers for student participation in sea
exploration and discovery. Through U.S. IOOS, forecast
ocean data will be harvested from the ephemeral ocean
snapshots produced by an ensemble of ocean models along the
same glider tracks as Challenger. The parallel observed and
forecast datasets, both evolving in real time, will be accessible
through the same OOI EV tools, enabling student participation
in a crowd-sourced ocean predictive skill experiment. The
result will satisfy one of the important goals of the Challenger
mission by enabling students to assess of the quality of the
ensemble of available global scale ocean models.
Student research team projects that use the new model data
comparison capabilities will be conducted during the summer
of 2014. Students will compare an ensemble of the global
ocean models along the high velocity transport pathways by
gliders on basin-scale missions, such as one that traverses the
northern side of the South Atlantic gyre along the Brazilian
shelfbreak. The lasting impact of the Challenger mission will
be a global fleet available to respond to events, an assessment
of the ocean models along the fastest ocean transport
pathways, and the establishment of a network of gliderports
for global response.
Keywords — Ocean Forecasting; Autonomous Underwater
Gliders; Challenger Glider Mission.
I. INTRODUCTION
Autonomous Underwater Gliders have been utilized by the
scientific and defense communities for a multitude of different
2. missions that cover all areas of the globe from the surface of
the ocean to 1000 meters below. Recently, long scale
endurance missions have started to become a focus. The
Challenger Glider Mission is one such mission whose aim is
to use gliders to explore five ocean basins covering 128,000
kilometers.
Figure 1: The projected paths of the Challenger Glider
Mission.
Two of the gliders that are involved in this Challenger
Glider Mission are Silbo and RU29. Silbo has not contributed
significantly to the mission since the Dobson et al. [5] article
where data from Silbo and RU29 were used to compare
against the then current ocean models. As such, an extension
on the analysis of the Silbo data is not needed. RU29,
however, has stopped in the Ascension Islands and flown all
the way to São Paulo, Brazil since the publication of the
Dobson et al. [5] article.
Figure 2: A map of the history of tracks covered by Rutgers Coastal
Ocean Observation Lab’s Challenger gliders. Basin scale missions,
in collaboration with Teledyne Webb Research and Universidad de
Las Palmas de Gran Canaria.
The data collected from the flight of RU29 from the
Ascension Islands to São Paulo, Brazil can contribute
significantly to our understanding of the accuracy of both the
American RTOFS ocean model and the European MyOcean
ocean model and expand upon the work done last year in the
Dobson et al. [5] article. This flight completes the examination
of the northern section of the South Atlantic gyre. While the
ocean forecast models currently assimilate data from an Argo
network of over 3000 drifters, assimilating glider data that
crosses frontal features may be beneficial to increasing the
forecast accuracy. Glider data can help to increase sampling
resolution in areas not covered extensively by Argo drifters.
Figure 3: A photograph of RU29, an autonomous underwater glider
that successfully crossed the Atlantic Ocean in 2014.Behind RU29,
the Oceanographic Research Vessle Alpha Delphini, from the
University of São Paulo
This study will report the results of student investigations
comparing temperature, salinity, and depth-averaged currents
between RU29 and the model forecasts. Preliminary student
observations along RU29’s flight indicate that the MyOcean
model, while different from RU29 on a wider area, was closer
to RU29 at points of discrepancy. The RTOFS model,
however, had fewer areas of discrepancy, but the
discrepancies that did exist were generally of a greater
magnitude.
II. METHODS
The two ocean forecasting models used in this paper are the
MyOcean model and the RTOFS model. The MyOcean model
is the result of collaboration between European countries such
as the United Kingdom, France, Germany, and Denmark. The
RTOFS model is created by the National Center for
Environmental Prediction, a subgroup of the National Oceanic
and Atmospheric Administration based in the United States.
Figure 4: Example of the path planning tools that can be made using
data from the ocean forecasting models RTOFS (left) and MyOcean
(right) by Universidad de Las Palmas de Grab Canaria.
3. The sensor used by the G2 category of gliders is a SeaBird
pumped Conductivity, Temperature and Depth (CTD) sensor.
Temperature and Salinity data is recovered from the glider and
thermal inertia from the conductivity sensor is corrected for
using the process from Kerfoot et al. [3]. This data is
compared to a section of the RTOFS model and the MyOcean
model simulations along the path taken by the glider (Figure
5).
Figure 5: The portion of RU29’s track that was used for comparison
to the models, focusing on the green, white, and red sections. This
track represents an east to west path along the northern side of the
South Atlantic Gyre.
The comparisons made in this paper are a result of an
analysis of temperature, salinity, and depth-averaged currents
made by the models and RU29. MyOcean and RTOFS data
was collected from respective Internet sources, while the
glider data was collected by RU29 (Figure 3). A series of
MATLAB scripts facilitated data processing and figure
creation. By comparing the in-situ glider data to data obtained
by the Argo Floats (Figures 7 & 9), we were able to confirm
the quality of the glider temperature and salinity observations
of the conditions of the water column. The most striking
observation is of the temperature profiles, where the deep data
from RU29, Argo, and RTOFS are similar, but MyOcean deep
temperatures are about 1˚C higher.
The temperature and salinity data collected by RU29 was
then compared to RTOFS and MyOcean (Figures 6 & 8). The
figures were created by observing the difference between
glider data and model predicted data. There was a general 1˚C
difference between the MyOcean and RU29 temperature data
(Figure 6b), whereas the discrepancies between the RTOFS
and RU29 data were less widespread but more significant
(Figure 6a). The most variation between the two models and
RU29 exist within the first 300 meters of the water column, as
shown in figures 6 and 8. Hence, the remainder of this paper
will focus on analyses of depths above 300 meters.
Figure 6: The difference in temperature between the RTOFS model
with RU29 (a) and the MyOcean model with RU29 (b).
Figure 7: Temperature depth profile comparison between RU29,
RTOFS, MyOcean, and Argo Float data at a sample point.
Figure 8: The difference in salinity between the RTOFS model with
RU29 (a) and the MyOcean model with RU29 (b).
a
b
a
b
4. Figure 9: Salinity depth profile comparison between RU29, RTOFS,
MyOcean, and Argo Float data at a sample point.
III. RESULTS
RU29’s mission from Ascension Island to São Paulo,
Brazil lasted from November 15, 2013 to May 18, 2014. It
traveled 4,420 km crossing the Atlantic on the northern part of
the South Atlantic gyre. An analysis of temperature, salinity
and currents was conducted on three areas of interest: a 1,262
km leg off the coast of Ascension Island, a 265km leg off the
coast of Brazil, and a 179km leg on the Brazilian continental
shelf (Figure 5).
A. Turtle Tracks
The first area of interest occurred from November 15, 2013
to December 30, 2013. This section will be referred to as
“Turtle Tracks” and is denoted by the green section of the
track in Figure 5. It is worth noting because the migration path
of Green Sea Turtles between Ascension Island and Brazil
runs along this path.
An analysis of temperature and salinity was conducted.
There was not much disparity in temperature between the two
models and RU29 (Figure 10). However a difference between
RU29 and MyOcean exists at the surface and between 250 and
300 meters (Figures 10b &10c). The salinities of RTOFS and
RU29 have larger differences than the salinities of RU29 and
MyOcean. Most noticeable is the consistent subsurface
salinity peak near 100 m visible in RU29 and MyOcean, but
missing from RTOFS. Neither model accurately depicts the
depth averaged current vectors measured by RU29 along this
area of the track.
Figure 11: Temperature comparison between RTOFS (a), RU29 (b),
and MyOcean (c) for the Turtle Tracks.
Figure 12: Current Vector comparison between RTOFS (a), RU29
(b), and MyOcean (c) for the Turtle Tracks.
B. Deep Eddy
The second area of interest occurred from April 26, 2014
to May 6, 2014. This section will be referred to as the “Deep
Eddy” and is denoted by the white section of the track in
Figure 5. It is worth noting because of the strong presence of
an eddy. This is an area of strong meso-scale activity due to
the Brazil Current[6] and the data collected with the glider can
provide vertical and horizontal in-situ details that are not
possible with other methods
There is evidence of a deep-water clockwise spinning eddy
in the current plot of RU29 (Figure 15b), which is also seen in
its temperature and salinity plots (Figure 13b & 14b). This
eddy appears in the RTOFS current plot as well, with the same
clockwise direction (Figure 15a). Although this eddy is
present in the same spot as RU29 in both RTOFS’ temperature
and salinity plots, it manifests less gradually than the eddy
shown in RU29’s temperature and salinity plots (Figures 13a,
13b, 14a & 14b). MyOcean does not recognize the eddy
structure at all (Figures 13c, 14c, & 15c).
a
b
c
a
b
c
Figure 10: Temperature comparison between RTOFS (a), RU29 (b),
and MyOcean (c) for the Turtle Tracks.
a
b
c
5. Figure 13: Temperature comparison between RTOFS (a), RU29 (b),
and MyOcean (c) for the Deep Eddy.
Figure 14: Salinity comparison between RTOFS (a), RU29 (b), and
MyOcean (c) for the Deep Eddy.
Figure 15: Current Vector comparison between RTOFS (a), RU29
(b), and MyOcean (c) for the Deep Eddy.
C. Continental Shelf and Cabo Frio Eddy
The third area of interest occurred from May 7, 2014 to
May 18, 2014. This section will be referred to as “Continental
Shelf and Cabo Frio Eddy” and is denoted by the red section
of the track in Figure 5. It is worth noting because global
models often have difficulty resolving features in shallow
waters and the Cabo Frio Eddy is a well known eddy.
There is evidence of a shallow-water counter-clockwise
spinning eddy in the current plot of RU29 (Figure 18b), which
is also seen in its temperature and salinity plots (Figure 16b &
17b). This eddy appears in the MyOcean current plot as well,
with the same counter-clockwise direction (Figure 18a). The
eddy is present in the same spot as RU29 in the temperature
and currents plots but the MyOcean model elongates the eddy
(Figure 16b, 16c, 18b, & 18c). The MyOcean salinity plot also
shows the eddy elongated, however, the eddy is shifted
towards the coast. (Figure 17b &17c). RTOFS does not
recognize the eddy structure at all (Figures 13c, 14c, & 15c).
On the continental shelf, possibly because MyOcean
elongates the Cabo Frio eddy, the temperature and salinity it
reports for the continental shelf are too warm and salty
(Figures 16b, 16c, 17b, & 17c). While MyOcean is incorrect,
it is not radically different from RU29, especially closest to
the continent. RTOFS, however, reports noticeably warmer
and saltier water in the very shallow waters (Figures 16a &
17a).
Figure 16: Temperature comparison between RTOFS (a), RU29 (b),
and MyOcean (c) for the Continental Shelf and Cabo Frio Eddy.
Figure 17: Salinity comparison between RTOFS (a), RU29 (b), and
MyOcean (c) for the Continental Shelf and Cabo Frio Eddy.
a
b
c
a
b
c
a
b
c
a
b
c
a
b
c
6. Figure 18: Current Vector comparison between RTOFS (a), RU29
(b), and MyOcean (c) for the Continental Shelf and Cabo Frio Eddy.
IV. DISCUSSION
Two forecasting models, MyOcean and RTOFS have been
studied in comparison to the glider RU29. The findings
presented have lead to the conclusion that these two models
have inconsistencies with in-situ glider data. Neither model
can be considered superior as in certain areas, such as the
“Deep Eddy”, the MyOcean model was lacking features in the
ocean’s structure whereas the RTOFS model did not predict
the existence of the Cabo Frio Eddy. Both the RTOFS model
and the MyOcean model contain some important features that
correspond with the glider data yet both also do not always
reflect the structure apparent in the in-situ glider data.
Over the length of the RU29 Ascension Island to Brazil
flight, the MyOcean model has a fairly consistent 1˚C to 2˚C
difference in temperature from RU29, however there were not
many places in either salinity or temperature that the
MyOcean model differed notably from RU29. In comparison,
the RTOFS model was fairly consistent with the RU29 data at
lower depths but had very large discrepancies in magnitude at
certain locations.
Ocean forecast models have become an indisputable tool
for scientists and students, with the ability to resolve eddy
structures and incorporate new data. They are easily accessible
to researchers around the world. Such improvements to the
models come from data taken from satellite and Argo floats
that measure sea-surface temperature, sea surface height, and
temperature/salinity profiles. In order to further improve the
models, more data must be integrated from other sources. This
will help advance forecast modeling in predicting features
such as hurricane intensity.
Autonomous Underwater Gliders are able to contribute to
the ocean forecast modeling because of their ability to traverse
previously under-sampled regions of the ocean. It is crucial to
the future of ocean modeling that glider-collected data be
incorporated especially where areas of disagreement between
the models occur.
V. ACKNOWLEDGEMENTS
The Challenger Glider Mission is growing global
partnership of glider operators, scientists, educators and students
coordinated by Rutgers University and endorsed by the Challenger
Society. The results presented in this paper were initiated in a
Rutgers research course and completed by three undergraduate
summer interns (Rachael Sacatelli, Tobias Schofield, and Katherine
Todoroff) supported by Teledyne Webb Research and four U.S.
Naval Academy Interns (Angela Carandang, Alyson Eng, Ian Lowry,
and Harrison Mather). Glider path planning and model/data
comparison activities are led by Nilsen Strandskov (Rutgers) and
Antonio Ramos (Universidad de Las Palma de Gran Canaria) with
cyber infrastructure support provided by John Kerfoot (Rutgers).
Glider operators include Chip Haldeman, Dave Aragon, Tina Haskin
(Rutgers) and Ben Alsup (TWR). The RU29 deployment in South
Africa was enabled by the University of Cape Town, The Nansen-
Tutu Center, and the South African Marine Engineering & Robotics
Centre at the Council for Scientific and Industrial Research (CSIR).
The recovery and redeployment on Ascension Island was facilitated
by the British Royal Navy, the U.S. Navy, and Ascension Island
Fishing Charters (AIFC). The recovery and redeployment of RU29 in
São Paulo, Brazil was enabled by University of São Paulo. RU29
mission support is provided by the U.S. Integrated Ocean Observing
System, the U.S. Office of Naval Research – Global, and the G.
Unger Vetlessen Foundation. Technology support provided by
Teledyne Webb Research, Iridium and CLS America. Argo data was
collected and made freely available by the International Argo
Program and the national programs that contribute to it.
(http://www.argo.ucsd.edu, http://argo.jcommops.org). The Argo
Program is part of the Global Ocean Observing System.
VI. REFERENCES
[1] Glenn, S., + 47 co-Authors, Process-driven improvement to
hurricane intensity and storm surge forecasts in the Mid-
Atlantic Bight: Lessons learned from Hurricanes Irene and
Sandy. Oceans’13 MTS/IEEE Bergen.
[2] Glenn, S., Kohut, J., McDonnell, J., Seidel, D., Aragon, D.,
Haskins, T., Handel, E., Haldeman, C., Heifetz, I., Kerfoot,
J., Lemus, E., Lictenwalder, S., Ojanen, L., Roarty, H.,
Atlantic Crossing Students, Jones, C., Webb, D., Schofield,
O. 2011. The Trans-Atlantic Slocum glider expeditions: A
catalyst for undergraduate participation in ocean science
and technology. Marine Technology Society 45: 75-90.
[3] Kerfoot, J., S. Glenn, H. Arango, C. Haldeman, C. Jones
and D. Pinkel, 2010. Correction and comparison of pumped
and non-pumped CTS sensors on the Slocum Glider, EOS
Transactions, AGU, 91(26), Ocean Sci. Meet. Suppl.,
Abstract IT35B-03.
[4] Schofield, O., Kohut, J., Glenn, S., Morell, J., Capella, J.,
Corredor, J., Orcutt, J., Arrott, M., Krueger, I., Meisinger,
M., Peach, C., Vernon, F., Chave, A., Chao, Y., Chien, S.,
Thompson, D., Brown, W., Oliver, M., Boicourt, W. 2010.
A regional Slocum glider network in the Mid-Atlantic
coastal waters leverages broad community engagement.
Marine Technology Society 44(6): 64-74.
[5] Dobson, C., Mart, J., Strandskov, N., Kohut, J., Schofield,
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