Identification of news partners of Aurora-C

National audienc

Frequency and angular variations of land surface microwave emissivities : can we estimate SSM/T and AMSU emissivities from SSM/I emissivities

International audienc

Suivi des dynamiques d'inondation à l'échelle globale sur une décennie

Although they only cover ~6% of the Earth's ice-free land surfaces (~8.6 millions km2), natural wetlands and rice paddies play a key role in climate and hydrological processes. Firstly, they represent the world's largest methane source (CH4), the only one dominated by climate variations and account for ~40% of CH4 emitted annually to the atmosphere. In addition, wetlands play a major role for local hydrological system as they contribute in part of the fresh water input in the Oceans by river discharge that greatly influences the ocean circulation through the evolution of the Sea Surface Temperature. Approximately 60% of wetlands are only inundated at some period in the year leading to large uncertainties on their seasonal and inter-annual extents. This is particularly the case for tropical regions subject to the annual rain season as well as Boreal regions subject to the snow melt period. Despite the recognition of their role in climate and hydrological process, as well as their importance in water resources management, wetlands extent and dynamic databases still suffer of a lack of reliable information at global or regional scales over long time period. Characterizing wetlands and their dynamics over large geographical region has been investigated using different techniques with varying degrees of success. Datasets based on soil and vegetation observations represent realistic global wetland distributions, but unfortunately they suffer from a lack of information on temporal and spatial dynamics. In that context, satellite observations provide a means of monitoring wetlands and their dynamics at global and regional scales over long time periods. The objective of this study is to present a new globally applicable remote sensing technique, considering a suite of complementary satellite observations developed to quantify spatial and temporal dynamics of wetlands. The technique it self is based on the detection of inundations at the global scale using the passive microwave land-surfaces emissivities estimated from SSM/I observations, and the use of ERS scatterometer and AVHRR visible and near infrared reflectances to estimate the vegetation contribution to the passive microwave signal. Monthly wetlands extents are now estimated at the global scale over the 9-years 93-2001 period and analyzed regarding to spatial patterns and temporal evolutions. A first results evaluation is made using independent datasets such as land surfaces databases, rain fall rate from GPCP products and water level from radar altimeter measurements. The spatial and temporal wetlands estimations, comprising natural wetlands, irrigated rice culture and lake/river are relevant when compare to static wetlands observations databases. Over the globe, the results show also a high correlation with the GPCP rain data product over the 9 years of study. The correlation over specific regions will be discussed. When focusing around specific areas such as the river basins of the Ganges, the Amazon or Parana Rivers or the Congo-Niger regions, the analysis based on the comparison with water river levels derived from radar altimeter observations show a similar seasonal cycle over the 9 years. These results are encouraging and future studies could now focus on wetlands dynamics as a proxy to study for instance the impacts of ENSO or the monsoons regimes on continental processes. A promising synergy with radar altimetry that could also bring new information related to hydrological parameters, such as river discharges, is under now investigation. Finally, this study stresses the need for development of quality longer satellite estimated wetlands dynamics till upcoming days

Several Signaling Pathways Are Involved in the Control of Cattle Oocyte Maturation

International audienc

Co-click’eau, a participatory method for land-use scenarios in water catchments

Agricultural use of pesticides and nitrogen has negatively impacted drinking water quality. In France, 1000 water catchments now face a legal obligation to develop and implement action plans to reduce such pollution. Unfortunately, the action plans suffer from delays, are developed mechanically to strictly comply with a preset list of measures resulting in minimal changes in practices. Their impact is generally insufficient to preserve or restore water quality. In this context, the Co-click’eau method was proposed to elicit the development of locally-relevant catchment action plans by drawing on stakeholder participation and modeling for the design and assessment of scenarios on land-use changes at the whole-catchment scale. The method was tested in 2011–2012 in three different catchments. Our results show that it has a significant role to play in facilitating the development of catchment-specific action plans for which local stakeholders can feel a sense of ownership and commitment. Co-click’eau is also valuable in enhancing collective action by eliciting a process where local stakeholders share their knowledge and explore possible futures. Participation of a wide diversity of local stakeholders, along with a flexible modeling approach makes it possible to take into account local constraints and helps to break down local lock-ins

Demonstration of the assimilation of the future SMOS data by using field and airborne campaigns

International audienc