2015 European Geosciences Union General Assembly
Aquarius-related papers presented at the 2015 European Geosciences Union (EGU) General Assembly addressed air-sea fluxes, near-surface salinity stratifications, sensor capability and atmospheric corrections, data validation, and more. The EGU General Assembly is the largest geosciences meeting in Europe and covers all disciplines of the Earth, planetary and space sciences.
3D Dynamics of Freshwater Lenses in the Near-Surface Layer of the Tropical OceanSoloviev, A. and Dean, C. (17-Apr-15). Convective rains in the Intertropical Convergence Zone (ITCZ) produce lenses of freshened water on the ocean surface. These lenses are localized in space and typically involve both salinity and temperature anomalies. Due to significant density anomalies, strong pressure gradients develop, which result in lateral spreading of freshwater lenses in a form resembling gravity currents.
Air-sea Fluxes and Satellite-based Estimation of Water Masses FormationSabia, R., Klockmann, M., Fernandez-Prieto, D., and Donlon, C. (17-Apr-15). Recent work linking satellite-based measurements of sea surface salinity (SSS) and sea surface temperature (SST) with traditional physical oceanography has demonstrated the capability of generating routinely satellite-derived surface T-S diagrams and analyze the distribution/dynamics of SSS and its relative surface density with response to in-situ measurements. Even more recently, this framework has been extended by exploiting these T-S diagrams as a diagnostic tool to derive water masses formation rates and areas.
An Examination of the Sea Surface Salinity - Fresh Water Flux Relationship Using Satellite Observations from SMOS and AquariusXie P., Kumar, A., Xue, Y., and Liu, T. (17-Apr-15). Relationship between the sea surface salinity (SSS) and the oceanic fresh water flux (E-P) is examined using the SSS retrievals derived from the passive microwave (PMW) observations aboard the SMOS and Aquarius satellites, the CMORPH integrated satellite precipitation estimates (P) and the evaporation data (E) produced by the NCEP Climate Forecast System (CFS) reanalysis.
Multi-dimensional Interpolation of SMOS Sea Surface Salinity with Surface Temperature and In Situ Salinity DataNardelli, B.B., Droghei, R., and Santoleri, R. (17-Apr-15). Availability of accurate remotely-sensed sea surface salinity (SSS) measurements is crucial to investigating fundamental aspects of the global hydrological cycle, ocean dynamics and marine biogeochemistry. The European Space Agency (ESA) Soil Moisture Ocean Salinity (SMOS) mission has been specifically designed for this aim. However, SMOS data display a high level of noise with respect to the signal they have to detect.
Near Surface Salinity Stratifications from Aquarius, Argo and an Ocean ModelSong, Y.T and Moon, J-H. (17-Apr-15). By comparing a newly available Aquarius-derived sea surface salinity (SSS) with the Argo in-situ measurements and an ocean circulation model, we have examined the near surface salinity stratifications in the tropical Atlantic and Indian Oceans.
Persistence of Rainfall Imprint on SMOS Sea Surface SalinityBoutin, J., Reverdin, G., and Martin, N. (17-Apr-15). The Soil Moisture and Ocean Salinity (SMOS) satellite mission monitors sea surface salinity (SSS) over the global ocean for more than 5 years. In previous studies, Boutin et al. (2014) have shown a clear freshening of SMOS SSS under rain cells of about -0.14pss/mm/hr at moderate wind speed (3-12m/s). This order of magnitude is compatible with in situ drifters observations taken at 45cm depth while SMOS SSS are at about 1cm depth and at a mean spatial resolution of 43km.
Satellite and In Situ Salinity: Understanding Near-surface Stratification and Sub-footprint VariabilityBoutin, J., Chao, Y., Asher, W., Delcroix, T., Drucker, R., Drushka, K., Kolodziejczyk, N., Lee, T., Reul, N., Reverdin, G., Schanze, J., Soloviev, A., Yu, L., Anderson, J., Brucker, L., Dinnat, E., Garcia, A., Jones, W., Maes, C., Meissner, T., Tang, W., Vinogradova, N., and Ward, B. (17-Apr-15). Remote sensing of salinity using satellite-mounted microwave radiometers provides new perspectives for studying ocean dynamics and the global hydrological cycle. Calibration and validation of these measurements is challenging because satellite and in situ methods measure salinity differently.
Sensor Capability and Atmospheric Correction in Ocean Colour Remote SensingEmberton, S., Chittka, L., Cavallaro, A., and Wang, M. (17-Apr-15). Accurate correction of the corrupting effects of the atmosphere and the water's surface are essential in order to obtain the optical, biological and biogeochemical properties of the water from satellite-based multi- and hyper-spectral sensors. The major challenges now for atmospheric correction are the conditions of turbid coastal and inland waters and areas in which there are strongly-absorbing aerosols.
The Role of Time- and Space Scales in Estimating the Relative Importance of Isopycnal and Diapycnal Oceanic MixingSchanze, J. and Schmitt, R. (17-Apr-15). Large-scale thermal forcing and freshwater fluxes play an essential role in setting the ocean's temperature and salinity. The ratio of the relative contributions of haline and thermal forcing in the mixed layer is maintained by large-scale surface fluxes, leading to important consequences for mixing in the ocean interior.
Validation of the New Algorithm for Rain Rate Retrieval from AMSR2 Data Using TMI Rain Rate ProductZabolotskikh, E. and Chapron, B. (17-Apr-15). A new algorithm is derived for rain rate (RR) estimation from Advanced Microwave Sounding Radiometer 2 (AMSR2) measurements taken at 6.9, 7.3, and 10.65GHz. The algorithm is based on the numerical simulation of brightness temperatures (TB) for AMSR2 lower frequency channels, using a simplified radiation transfer model.