Airports are recognized to become critical areas in the future given the expected doubling in air... more Airports are recognized to become critical areas in the future given the expected doubling in air traffic by 2020. The increased density of aircrafts in the airport airspaces calls for improved systems and products to monitor in real-time potential hazards and thus meet the airport objectives in terms of safety and throughput. Among all meteorological hazards, convection is certainly the
Météo-France has national and international responsibilities to agencies fighting marine oil poll... more Météo-France has national and international responsibilities to agencies fighting marine oil pollution. Météo-France can intervene at a national level within the spill response plan POLMAR-MER in case of a threat for the French coastline, and at an international level within the Marine Pollution Emergency Response Support System (MPERSS) for the high seas. In order to answer to these commitments, Météo-France developed MOTHY, a pollutant drift model. The model is operational and can be used 24h/24 for oil spills or drifting objects. MOTHY is an integrated system that includes an oil spill model linked to an hydrodynamic coastal ocean model with real time atmospheric forcing from a global or limited area model. MOTHY has proved its efficiency, giving results very closed to the reality, during the Erika crisis (December 1999) in the Bay of Biscay. So far, the effects of the general circulation and the associated large scale currents are not represented in the model. The present work focuses on evaluating the effects of these currents and comparing different methods to represent them in the MOTHY system. Currents from different origins can be used and the first part of this work is to compare them:
In order to promote the use of sea-sate related parameters and in particular to introduce new war... more In order to promote the use of sea-sate related parameters and in particular to introduce new warning criteria for rogues waves and dangerous sea-states within GMDSS, WP8 main tasks consisted in to propose updates of WMO regulations and to interact with some end users to define specific products with the aid of physical, statistical and deterministic wave models. To find
The Erika sank on December 12, 1999 of the coast of Brittany. Fuel oil slicks drifted for two wee... more The Erika sank on December 12, 1999 of the coast of Brittany. Fuel oil slicks drifted for two weeks before polluting roughly 400 km of coastline. Movement forecasts were made by Météo-France (French National Weather Service) in close collaboration with the Cedre. The Erika accident showed that a working tool existed for forecasting oil slick movements, providing cleanup authorities with essential decision-making support. The crisis also showed that this was not enough and that correct forecasting requires appropriate observation capabilities. Forecasting models must be supplied with initial conditions that represent the actual situation. Moreover, the accident demonstrated that making use of the full potential of forecasting requires the ability to integrate important information, including methods and tools. Current projects such as CEP&M or Lit'eau are collaborations between Météo-France, the CEDRE and IFREMER, and should produce significant improvements in forecasting tools.
MOTHY (Modèle Océanique de Transport d'Hydrocarbures) is a pollutant drift model, developed a... more MOTHY (Modèle Océanique de Transport d'Hydrocarbures) is a pollutant drift model, developed and operated by Météo-France. MOTHY includes hydrodynamic coastal ocean modelling and real time atmospheric forcing from a global meteorological model. Pollutants can be oil or floating objects. To improve forecasts on the Mediterranean Sea, several methods were tested to inject large scale currents (permanent part) into the MOTHY
International Oil Spill Conference Proceedings, 2003
MOTHY (Modèle Océanique de Transport d'Hydrocarbures) is a pollutant drift model, developed and o... more MOTHY (Modèle Océanique de Transport d'Hydrocarbures) is a pollutant drift model, developed and operated by Météo-France. MOTHY includes hydrodynamic coastal ocean modelling and real time atmospheric forcing from a global meteorological model. Pollutants can be oil or floating objects. To improve forecasts on the Mediterranean Sea, several methods were tested to inject large scale currents (permanent part) into the MOTHY system. The best results were obtained with monthly means of currents at 5 meters (from Mercator system). The addition of altimetric corrections improved the results.
Météo-France, due to its responsibilities in POLMAR-MER and MPERSS, developed MOTHY, a pollutant ... more Météo-France, due to its responsibilities in POLMAR-MER and MPERSS, developed MOTHY, a pollutant drift model. To improve forecasts on the Mediterranean Sea, several methods were tested to inject large scale currents (permanent part) into the MOTHY system. The best results were obtained with monthly means of currents at 5 meters (from Mercator prototype). The addition of altimetric corrections improved the results again. The potential benefit of currents from operational oceanography system is so obviously higher since forecasts will be available.
A mesoscale non-hydrostatic atmospheric model has been coupled with a mesoscale oceanic model. Th... more A mesoscale non-hydrostatic atmospheric model has been coupled with a mesoscale oceanic model. The case study is a four-day simulation of a strong storm event observed during the SEMAPHORE experiment over a 500´500 km 2 domain. This domain encompasses a thermohaline front associated with the Azores current. In order to analyze the eect of mesoscale coupling, three simulations are compared: the ®rst one with the atmospheric model forced by realistic sea surface temperature analyses; the second one with the ocean model forced by atmospheric ®elds, derived from weather forecast re-analyses; the third one with the models being coupled. For these three simulations the surface¯uxes were computed with the same bulk parametrization. All three simulations succeed well in representing the main oceanic or atmospheric features observed during the storm. Comparison of surface ®elds with in situ observations reveals that the winds of the ®ne mesh atmospheric model are more realistic than those of the weather forecast re-analyses. The low-level winds simulated with the atmospheric model in the forced and coupled simulations are appreciably stronger than the re-analyzed winds. They also generate stronger uxes. The coupled simulation has the strongest surface heat¯uxes: the dierence in the net heat budget with the oceanic forced simulation reaches on average 50 Wm A2 over the simulation period. Sea surface-temperature cooling is too weak in both simulations, but is improved in the coupled run and matches better the cooling observed with drifters. The spatial distributions of sea surface-temperature cooling and surface¯uxes are strongly inhomogeneous over the simulation domain. The amplitude of the¯ux variation is maximum in the coupled run. Moreover the weak correlation between the cooling and heat¯ux patterns indicates that the surface¯uxes are not responsible for the whole cooling and suggests that the response of the ocean mixed layer to the atmosphere is highly non-local and enhanced in the coupled simulation.
On November 13 th 2002 the tanker Prestige was off the coast of Galicia, Spain, when it suffered ... more On November 13 th 2002 the tanker Prestige was off the coast of Galicia, Spain, when it suffered severe structural failure of the starboard cargo tanks. The ship was tugged away from the coast. On November 19 th , the vessel broke into two sections at about one hundred and thirty miles from the Galicia coast. The two parts of the wreck sank at a 3500 meters depth. More than 60,000 tons of heavy fuel were released into the marine environment. At sea containment and recovery, and aerial surveillance of the oil, were hampered by the weather and the oil remained at sea for a considerable period of time. Diffuse pollution was still reaching the coastline more than six months after the break.
Airports are recognized to become critical areas in the future given the expected doubling in air... more Airports are recognized to become critical areas in the future given the expected doubling in air traffic by 2020. The increased density of aircrafts in the airport airspaces calls for improved systems and products to monitor in real-time potential hazards and thus meet the airport objectives in terms of safety and throughput. Among all meteorological hazards, convection is certainly the
Météo-France has national and international responsibilities to agencies fighting marine oil poll... more Météo-France has national and international responsibilities to agencies fighting marine oil pollution. Météo-France can intervene at a national level within the spill response plan POLMAR-MER in case of a threat for the French coastline, and at an international level within the Marine Pollution Emergency Response Support System (MPERSS) for the high seas. In order to answer to these commitments, Météo-France developed MOTHY, a pollutant drift model. The model is operational and can be used 24h/24 for oil spills or drifting objects. MOTHY is an integrated system that includes an oil spill model linked to an hydrodynamic coastal ocean model with real time atmospheric forcing from a global or limited area model. MOTHY has proved its efficiency, giving results very closed to the reality, during the Erika crisis (December 1999) in the Bay of Biscay. So far, the effects of the general circulation and the associated large scale currents are not represented in the model. The present work focuses on evaluating the effects of these currents and comparing different methods to represent them in the MOTHY system. Currents from different origins can be used and the first part of this work is to compare them:
In order to promote the use of sea-sate related parameters and in particular to introduce new war... more In order to promote the use of sea-sate related parameters and in particular to introduce new warning criteria for rogues waves and dangerous sea-states within GMDSS, WP8 main tasks consisted in to propose updates of WMO regulations and to interact with some end users to define specific products with the aid of physical, statistical and deterministic wave models. To find
The Erika sank on December 12, 1999 of the coast of Brittany. Fuel oil slicks drifted for two wee... more The Erika sank on December 12, 1999 of the coast of Brittany. Fuel oil slicks drifted for two weeks before polluting roughly 400 km of coastline. Movement forecasts were made by Météo-France (French National Weather Service) in close collaboration with the Cedre. The Erika accident showed that a working tool existed for forecasting oil slick movements, providing cleanup authorities with essential decision-making support. The crisis also showed that this was not enough and that correct forecasting requires appropriate observation capabilities. Forecasting models must be supplied with initial conditions that represent the actual situation. Moreover, the accident demonstrated that making use of the full potential of forecasting requires the ability to integrate important information, including methods and tools. Current projects such as CEP&M or Lit'eau are collaborations between Météo-France, the CEDRE and IFREMER, and should produce significant improvements in forecasting tools.
MOTHY (Modèle Océanique de Transport d'Hydrocarbures) is a pollutant drift model, developed a... more MOTHY (Modèle Océanique de Transport d'Hydrocarbures) is a pollutant drift model, developed and operated by Météo-France. MOTHY includes hydrodynamic coastal ocean modelling and real time atmospheric forcing from a global meteorological model. Pollutants can be oil or floating objects. To improve forecasts on the Mediterranean Sea, several methods were tested to inject large scale currents (permanent part) into the MOTHY
International Oil Spill Conference Proceedings, 2003
MOTHY (Modèle Océanique de Transport d'Hydrocarbures) is a pollutant drift model, developed and o... more MOTHY (Modèle Océanique de Transport d'Hydrocarbures) is a pollutant drift model, developed and operated by Météo-France. MOTHY includes hydrodynamic coastal ocean modelling and real time atmospheric forcing from a global meteorological model. Pollutants can be oil or floating objects. To improve forecasts on the Mediterranean Sea, several methods were tested to inject large scale currents (permanent part) into the MOTHY system. The best results were obtained with monthly means of currents at 5 meters (from Mercator system). The addition of altimetric corrections improved the results.
Météo-France, due to its responsibilities in POLMAR-MER and MPERSS, developed MOTHY, a pollutant ... more Météo-France, due to its responsibilities in POLMAR-MER and MPERSS, developed MOTHY, a pollutant drift model. To improve forecasts on the Mediterranean Sea, several methods were tested to inject large scale currents (permanent part) into the MOTHY system. The best results were obtained with monthly means of currents at 5 meters (from Mercator prototype). The addition of altimetric corrections improved the results again. The potential benefit of currents from operational oceanography system is so obviously higher since forecasts will be available.
A mesoscale non-hydrostatic atmospheric model has been coupled with a mesoscale oceanic model. Th... more A mesoscale non-hydrostatic atmospheric model has been coupled with a mesoscale oceanic model. The case study is a four-day simulation of a strong storm event observed during the SEMAPHORE experiment over a 500´500 km 2 domain. This domain encompasses a thermohaline front associated with the Azores current. In order to analyze the eect of mesoscale coupling, three simulations are compared: the ®rst one with the atmospheric model forced by realistic sea surface temperature analyses; the second one with the ocean model forced by atmospheric ®elds, derived from weather forecast re-analyses; the third one with the models being coupled. For these three simulations the surface¯uxes were computed with the same bulk parametrization. All three simulations succeed well in representing the main oceanic or atmospheric features observed during the storm. Comparison of surface ®elds with in situ observations reveals that the winds of the ®ne mesh atmospheric model are more realistic than those of the weather forecast re-analyses. The low-level winds simulated with the atmospheric model in the forced and coupled simulations are appreciably stronger than the re-analyzed winds. They also generate stronger uxes. The coupled simulation has the strongest surface heat¯uxes: the dierence in the net heat budget with the oceanic forced simulation reaches on average 50 Wm A2 over the simulation period. Sea surface-temperature cooling is too weak in both simulations, but is improved in the coupled run and matches better the cooling observed with drifters. The spatial distributions of sea surface-temperature cooling and surface¯uxes are strongly inhomogeneous over the simulation domain. The amplitude of the¯ux variation is maximum in the coupled run. Moreover the weak correlation between the cooling and heat¯ux patterns indicates that the surface¯uxes are not responsible for the whole cooling and suggests that the response of the ocean mixed layer to the atmosphere is highly non-local and enhanced in the coupled simulation.
On November 13 th 2002 the tanker Prestige was off the coast of Galicia, Spain, when it suffered ... more On November 13 th 2002 the tanker Prestige was off the coast of Galicia, Spain, when it suffered severe structural failure of the starboard cargo tanks. The ship was tugged away from the coast. On November 19 th , the vessel broke into two sections at about one hundred and thirty miles from the Galicia coast. The two parts of the wreck sank at a 3500 meters depth. More than 60,000 tons of heavy fuel were released into the marine environment. At sea containment and recovery, and aerial surveillance of the oil, were hampered by the weather and the oil remained at sea for a considerable period of time. Diffuse pollution was still reaching the coastline more than six months after the break.
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