ALBERT

Description: The objective of this paper is to present the multi-orbit (MO) surface soil moisture (SM) and angle-binned brightness temperature (TB) products for the SMOS (Soil Moisture and Ocean Salinity) mission based on a new multi-orbit algorithm. The Level 3 algorithm at CATDS (Centre Aval de Traitement des Données SMOS) makes use of MO retrieval to enhance the robustness and quality of SM retrievals. The motivation of the approach is to make use of the longer temporal autocorrelation length of the vegetation optical depth (VOD) compared to the corresponding SM autocorrelation in order to enhance the retrievals when an acquisition occurs at the border of the swath. The retrieval algorithm is implemented in a unique operational processor delivering multiple parameters (e.g. SM and VOD) using multi-angular dual-polarisation TB from MO. A subsidiary angle-binned TB product is provided. In this study the Level 3 TB V310 product is showcased and compared to SMAP (Soil Moisture Active Passive) TB. The Level 3 SM V300 product is compared to the single-orbit (SO) retrievals from the Level 2 SM processor from ESA with aligned configuration. The advantages and drawbacks of the Level 3 SM product (L3SM) are discussed. The comparison is done on a global scale between the two datasets and on the local scale with respect to in situ data from AMMA-CATCH and USDA ARS Watershed networks. The results obtained from the global analysis show that the MO implementation enhances the number of retrievals: up to 9 % over certain areas. The comparison with the in situ data shows that the increase in the number of retrievals does not come with a decrease in quality, but rather at the expense of an increased time lag in product availability from 6 h to 3.5 days, which can be a limiting factor for applications like flood forecast but reasonable for drought monitoring and climate change studies. The SMOS L3 soil moisture and L3 brightness temperature products are delivered using an open licence and free of charge using a web application (https://www.catds.fr/sipad/). The RE04 products, versions 300 and 310, used in this paper are also available at ftp://ext-catds-cpdc:catds2010@ftp.ifremer.fr/Land_products/GRIDDED/L3SM/RE04/.

Description: The objective of this paper is to present the multi-orbit (MO) surface Soil Moisture (SM) and angle binned Brightness Temperature (TB) products for the SMOS (Soil Moisture and Ocean Salinity) mission based on the a new multi-orbit algorithm. The Level 3 algorithm at CATDS (Centre de Traitement Aval des Données SMOS) makes use of multi-orbit (multi-revisits) retrieval to enhance the robustness and quality of SM retrievals. The motivation of the approach is to make use of the temporal auto-correlation of the vegetation optical depth (VOD) to enhance the retrievals when an acquisition occurs at the border of the swath. The retrieval algorithm is implemented in a unique operational processor delivering multiple parameters (e.g. SM and VOD) using angular signatures, dual polarization and multiple revisits. A subsidiary angle binned TB product is provided. In this study the L3 TB V300 product is showcased and compared to SMAP (Soil Moisture Active Passive) TB. The L3 SM V300 product is compared to the single-orbit (SO) retrievals from Level 2 SM processor from ESA (European Space Agency) with aligned configuration. The advantages and drawbacks of the Level 3 SM product (L3SM) product are discussed. The comparison is done at global scale between the two datasets and at local scale with respect to in situ data from AMMA-CATCH and USDA-ARS WATERSHEDS networks. The results obtained from the global analysis show that the MO implementation enhances the number of retrievals up to 9 % over certain areas. The comparison with the in situ data shows that the increase of the number of retrievals does not come with a decrease of quality. But rather at the expense of an increased lag of product availability from 6 hours to 3.5 days which can be a limiting factor for forecast applications like flood forecast but reasonable for drought monitoring and climate change studies. The SMOS L3 soil moisture and L3 brightness temperature products are delivered using an open licence and free of charge by CATDS (http://www.catds.fr).

Description: In the present article, the mantle convection is simulated numerically using a temperature dependent non-linear viscoelastic model for the first time. The numerical domain of problem is con sidered as a 4000 km*2000 km rectangular box and the CFD simulation is performed using finite volume method. Unlike the previous works which had been investigated the mantle convection using the linear viscoelastic models or simple nonlinear inelastic viscous equations (such as power law or cross equations), it is solved via the nonlinear Giesekus constitutive equation. Because of large-scale creeping flow in geometry and time, it is shown that the results of Giesekus equation are more reliable for this problem. The main innovative aspects of current study is investigation of temperature dependency of rheological properties of mantle including viscosity, normal stress differences and relaxation time using appropriate equations of state. The variation of gravitational acceleration with depth of Earth and the effect of the work of stress field (viscous dissipation) on mantle convection are also simulated for the first time.

Description: Understanding current and possible future alterations of water resources under climate change and increased water demand allows for better water and environmental management decisions in arid regions. This study aims at analyzing the impact of groundwater demand and climate change on groundwater sustainability and hydrologic regime alterations in a wadi system in central Iran. A hydrologic model is used to assess streamflow and groundwater recharge of the Halilrood Basin on a daily time step under five different scenarios over the baseline period (1979–2009) and for two future scenario periods (near future: 2030–2059 and far future: 2070–2099). The Indicators of Hydrologic Alteration (IHA) with a set of 32 parameters are used in conjunction with the Range of Variability Approach (RVA) to evaluate hydrologic regime change in the river. The results show that groundwater recharge is expected to decrease and is not able to fulfill the increasing water demand in the far future scenario. The Halilrood River will undergo low and moderate streamflow alteration under both stressors during the near future as RVA alteration is classified as “high” for only three indicators, whereas stronger alteration is expected in the far future, with 11 indicators in the high range. Absolute changes in hydrologic indicators are stronger when both climate change and groundwater demand are considered in the far future simulations, since 27 indicators show significant changes, and the RVA shows high and moderate levels of changes for 18 indicators. Considering the evaluated RVA changes, future impacts on the freshwater ecosystems in the Halilrood Basin will be severe. The developed approach can be transferred to other wadi regions for a spatially distributed assessment of water resources sustainability.