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from large donors such as the World Bank and Asian Development Bank that want to help manage water resources more effectively and productively, but nobody has the proper data,” Bastiaanssen says, but he continues, “with Landsat we can map out soil moisture, water consumption, water stress, crop yield.” Increasingly, the World Bank must deal with the overdraft of aquifers. They have labeled the unsustainable water mining “critical” in the North China Plain, Jordan, Mexico, Northern India, Israel, Palestine and Yemen. Meanwhile, Landsat has helped the World Bank successfully manage water projects in China, Mexico, and Yemen, as well as Egypt, Saudi Arabia, Uzbekistan, and Kazakhstan. In Turkey, Pakistan, Sri Lanka, India and China remote sensing has been demonstrated as a key tool for the strategic planning of water productivity on a basin wide scale.
Water – Solvency – Spillover
Other countries make use of US landsat data.
Clark 10 (Stephen, Spaceflight Now, Jan. 13, http://spaceflightnow.com/news/n1001/13landsat/ accessed 7/4/110 CJQ
"We use Landsat 5 principally to determine how much water is consumed by vegetation on a monthly and annual basis," Allen said. "Our primary areas of focus are irrigated agriculture, forests, wetlands and native plants." Landsat satellites are currently collecting more than 300 scenes per day globally. Those images go into an online archive, providing free access to scientists over the Internet. "What we're seeing is people building up their own archives, and not only pulling down the most recent data over their sites, but they're going back in time and pulling down some of the thematic mapper data from the '80s," Quirk said. Tucker said there are no international satellites offering free access to to Landsat-type data, elevating the urgent need for a U.S. follow-on spacecraft. "This is what the United States has done, and this is why U.S. data are widely used by everyone," Tucker said. "The same is not true of China, the same is not true of India, and the same is not been true of other countries before." A European Space Agency Sentinel satellite scheduled for launch in about four years will collect data comparable to the Landsat system and provide it to international researchers at low costs, but LDCM should be operational by then. It's up to a dedicated control team to keep the remarkable Landsat legacy intact for another three years, long enough for a fresh satellite to take over the mantle.
Water – Solvency – Resolution
Landsats are key to checking water usage, key to management
Allen 6 (Richard, G., Dept. of Agricultural and Biological Engineering, Dept. of Civil Engineering, U. Idaho, http://www.idwr.idaho.gov/GeographicInfo/Landsat/PDFs/case_for_thermal_imager_on_Landsat.pdf, accessed 7/5/11) CJQ
Moderately High resolution. The 30 m short-wave resolution and 60 to 120 m thermal resolution of Landsat satellites is critical for the computation and mapping of evapotranspiration from individual irrigated fields. Water rights regulation and administration are critically tied to identification and quantification of water consumption on a field by field basis. The current ET mapping by the Idaho Department of Water Resources (IDWR) could not have been developed if the highresolution Landsat images with thermal (temperature) images had not been available. The high-resolution Landsat images provide a means for identifying the crop type for each field that is useful for characterizing trends in evapotranspiration and for establishing relationships between water consumption and crop type (for example work by the U.S. Bureau of Reclamation in California and Arizona). The detailed and accurate computation of evapotranspiration using Landsat satellite data is not possible with the 1 km resolution of MODIS and AVHRR satellites.
Water – Solvency – Hydrology
Modern hydrology relies on Landsats—can’t work without them.
Qin et al 8 (Changbo, Dept. Water Res. Beijing, Yangwen Jia, Dept. Water Res. Beijing, Z.(Bob) Su, Int'l Inst. For Geo-Inf. Sci. & Earth Obs.—Netherlands, Yaqin Qiu, Dept. Water Res. Beijing, Shen Suhui, Dept. Water Res. Beijing, http://www.mdpi.org/sensors/papers/s8074441.pdf, accessed 7/6/11) CJQ
With the rapid development and increased application of remote sensing technology, evapotranspiration calculation methods using remote sensing techniques have become a major trend for hydrological research in recent years. The data obtained from visible, near-infrared and thermal band can reflect the spatial and temporal distribution of surface features, which have a great importance in simulating the energy balance. The SEBAL (Surface Energy Balance Algorithm for Land) proposed by Bastiaanssen et al. [43], which is based on land surface parameters acquired with remote sensing techniques. It is a semi-empirical model applied in calculating the evapotranspiration and the main difficulty is to determine the “hot” pixel and the “cold” pixel which has a great effect on the final results. Norman and Kustas [44] proposed the TSEB (Two-Source Energy Balance) algorithm to calculate the evaporation from bare soil and transpiration from vegetation separately based on remote sensing data. The Surface Energy Balance System (SEBS) was developed by Su [28] to estimate the atmospheric turbulent fluxes and evaporative fraction using satellite earth observation data, in combination with meteorological information at proper scales. The system retrieves evapotranspiration (ET) using measurements of incoming surface radiation, surface skin temperature, surface meteorology, and surface and vegetation properties [45]. One of the advantages in this algorithm is applying both Bulk Atmospheric Similarity (BAS) and the Monin-Obukov atmospheric surface layer (ASL) similarity in the model, which can be used for regional and local scales respectively to determine the turbulent fluxes. Another important merit of SEBS is the inclusion of a physical model which takes surface heterogeneity into account in the estimation of the roughness height for heat transfer. The SEBS algorithm has been successfully applied for many applications of evaporation estimations in many different places with different scale [46-51].
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