A comparison between above-water surface and subsurface spectral reflectances collected over inland waters Asif M. Bhatti Kochi University of Technology, Japan, asifmumtaz.bhatti@kochi-tech.ac.jp Donald RundquistUniversity of drundquist1@unl.edu John SchallesCreighton University, jfsaqua@creighton.edu Luis RamirezUniversity of Nebraska-Lincoln, luisermz@yahoo.com Seigo NasuKochi University of Technology, Japan Bhatti, Asif M.; Rundquist, Donald; Schalles, John; Ramirez, Luis; and Nasu, Seigo, "A comparison between above-water surface and subsurface spectral reflectances collected over inland waters" (2009 AbstractThe objective of the research was to undertake a quantitative comparison of spectral-reflectance measurements made slightly above the surface of water bodies with the measurements made slightly below the surface. The study is focused on three rivers; two in Georgia, USA and one in Japan. As expected, the differences in reflectance are not constant and vary with the wavelength. The contribution of surface-reflection effects to the surface reflectance measured slightly above the water is both pronounced and highly variable, but although they do alter the magnitude of the upwelling signal, they do not change the general shape of the spectral profiles. The correction of surface-reflection effects by assuming a proportionality factor (ρ) is not considered to be efficient for inland fresh water bodies. For in situ spectroscopy, the recommended approach is to measure upwelling radiance slightly below the water's surface as a means of minimizing extraneous noise. Researchers should be aware of the potential for diminishing the validity of findings because of measurement errors.

This paper introduces the process of development and practical use implementation of an advanced river management system for supporting integrated water resources management practices in Asian river basins under the framework of GEOSS Asia water cycle initiative (AWCI). The system is based on integration of data from earth observation satellites and in-situ networks with other types of data, including numerical weather prediction model outputs, climate model outputs, geographical information, and socio-economic data. The system builds on the water and energy budget distributed hydrological model (WEB-DHM) that was adapted for specific conditions of studied basins, in particular snow and glacier phenomena and equipped with other functions such as dam operation optimization scheme and a set of tools for climate change impact assessment to be able to generate relevant information for policy and decision makers. In situ data were archived for 18 selected basins at the Data Integration and Analysis System (DIAS) of Japan and demonstration projects were carried out showing potential of the new system. It included climate change impact assessment on hydrological regimes, which is presently a critical step for sound management decisions. Results of such three case studies in Pakistan, Philippines, and Vietnam are provided here. integrated water resources management tools, climate change impact assessment, Asian river basins, Asian Water Cycle Initiative Citation: Koike T, Koudelova P, Jaranilla-Sanchez P A, et al. 2015. River management system development in Asia based on Data Integration and Analysis System (DIAS) under GEOSS. Science China: Earth Sciences, 58: 76 -95,The global Earth observation system of systems (GEOSS) Asian water cycle initiative (AWCI) was established in 2007 as a response to the recognized needs for accurate, timely, and long-term water cycle information to implement integrated water resources management (IWRM) practices and with regards to the commonality in the water-related issues and socio-economic needs in the Asia-Pacific region. Implementing IWRM at the river basin level, while respecting the physical, social and political context, is an essential element to managing water resources in a more sustainable way, leading to long-term social, economic and environmental benefits (GWP, 2009). It requires a wide range of disparate data from multiple disciplines and various sources and appropriate tools for processing these data and integrating and translating them into relevant information for water resources practitioners and policy decision makers. A system for supporting IWRM practices thus must be able to simulate and predict a wide range of flows from droughts to floods and to be applicable for long-term, cli-

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Remote sensing has emerged as a useful tool for monitoring spatial and temporal distribution of sediment fluxes in the water bodies. The large quantity of sediment transported by the river waters create a number of water resources and environmental problems and could shorten the useful life of many downstream reservoirs and dams. The objective of the present article is to quantify the distribution of suspended sediment by means of Advanced Land Observing Satellite/Advanced Visible and Near Infrared Radiometer type 2 (ALOS/AVNIR-2) and Systeme Pour l'Observation de la Terre (SPOT) satellite data. Multispectral remotely sensed algorithm was developed to investigate the distribution of suspended sediment in the Indus River, Pakistan, and Tarbela dam reservoir. Reflectance of ALOS/AVNIR-2 band 3 and band 4 and SPOT-2 satellite band 2 and band 3 was found to be the best predictor of suspended sediment concentration in the surface waters. To deal with the lack of in situ data, remotely sensed data are coupled with optical modeling and the desired parameter is derived by model inversion technique. The developed methodology is an effective and efficient tool for monitoring erosion, deposition areas, and sediment distribution in large rivers.