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An Improved Spatial Downscaling Procedure for TRMM 3B43 Precipitation Product Using Geographically Weighted Regression

Precipitation data at high spatio-temporal resolution are essential for hydrological, meteorological, and ecological research in local basins and regions. The coarse spatial resolution (0.25°) of Tropical Rainfall Measuring Mission (TRMM) 3B43 product is insufficient for practical requirements. In this paper, a multivariable geographically weighted regression (GWR) downscaling method was developed

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Abstract: This study aims to investigate separate and combined impacts of land-use and climate variability on hydrological components in the Johor River Basin (JRB), Malaysia. The Mann-Kendall and Sen’s slope tests were applied to detect the trends in precipitation, temperature and streamflow of the JRB. The Soil and Water Assessment Tool (SWAT) was calibrated and validated using measured monthly

Evaluation of three satellite precipitation products TRMM 3B42, CMORPH, and PERSIANN over a subtropical watershed in China

This study conducted a comprehensive evaluation of three satellite precipitation products (TRMM (Tropical Rainfall Measuring Mission) 3B42, CMORPH (the Climate Prediction Center (CPC) Morphing algorithm), and PERSIANN (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks)) using data from 52 rain gauge stations over the Meichuan watershed, which is a represent

Evaluation of six high-resolution satellite and ground-based precipitation products over Malaysia

Satellite precipitation products (SPPs) potentially constitute an alternative to sparse rain gauge networks for assessing the spatial distribution of precipitation. However, applications of these products are still limited due to the lack of robust quality assessment. This study compares daily, monthly, seasonal, and annual rainfall amount at 342 rain gauges over Malaysia to estimations using five

A new empirical procedure for estimating intra-annual heat storage changes in lakes and reservoirs : Review and analysis of 22 lakes

Evaporation is an important component of the water and energy balance of lakes and reservoirs. The energy balance combination method for estimating evaporation requires the heat storage changes (Qt) to be known. The lack of data on water temperature profiles and water depth fluctuations hinders routine computations of Qt. Following successful estimation of the soil heat flux density of land surfac

Estimation of reservoir discharges from Lake Nasser and Roseires Reservoir in the Nile Basin using satellite altimetry and imagery data

This paper presents the feasibility of estimating discharges from RoseiresReservoir (Sudan) for the period from 2002 to 2010 and Aswan High Dam/Lake Nasser(Egypt) for the periods 1999-2002 and 2005-2009 using satellite altimetry and imagerywith limited in situ data. Discharges were computed using the water balance of thereservoirs. Rainfall and evaporation data were obtained from public domain dat

Earth observation based assessment of the water production and water consumption of Nile basin agro-ecosystems

The increasing competition for water resources requires a better understanding of flows, fluxes, stocks, and the services and benefits related to water consumption. This paper explains how public domain Earth Observation data based on Moderate Resolution Imaging Spectroradiometer (MODIS), Second Generation Meteosat (MSG), Tropical Rainfall Measurement Mission (TRMM) and various altimeter measureme

Characterizing spatial and temporal variations of surface temperature of Lake Tana (Ethiopia) using MODIS data

The information of water surface temperature (WST) is essential for many applications such as the estimation of evaporation from lakes and reservoirs. Generally, there is rarely continuous long-term in-situ measurement of water surface temperature for most lakes especially in developing countries. The freely available satellite data is an alternative or even the only data source for obtaining WST

Icesat-derived water level variations of roseires reservoir (Sudan) in the Nile Basin

The information of water level variations in lakes and reservoirs is essential for many applications such as water resources management. The conventional in-situ measurements of water levels based on gauge station are often rarely available or difficult to be shared to the public especially for lakes in the developing countries and transboundary basins. Satellite altimetry provides an alternative

Effects of climate variability on evaporation in Dongping Lake, China, during 2003-2010

Based on two long-term, hourly (10:30-11:30 and 13:10-14:10) meteorological over-lake observations and data from Shenxian meteorological station, nearby Dongping Lake, the Penman-Monteith equation and reference evaporation ratio algorithm were used to calculate lake evaporation in Dongping Lake, China, from 2003 to 2010. The variation trend of evaporation of Dongping Lake was analyzed, and the inf

Monthly and annual validation of TRMM Mulitisatellite Precipitation Analysis (TMPA) products in the Caspian Sea Region for the period 1999-2003

Two Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) products i.e. 3-hourly TRMM 3B42 and monthly 3B43 data were validated using 39 rain gauge stations in the Caspian Sea Region (CSR) in Iran with complex topography. The period 1999-2003 were selected. The validations were performed at monthly and annual scales. Results showed that both TRMM 3B42 and 3B43 can

Using fuzzy approach to build a continuous relationship between SCS curve number and soil properties

The commonly used Soil Conservation Service Curve Number (SCS-CN) for surface runoff modeling is largely dependent on the Hydrologic Soil Groups (HSGs) which are derived through aggregation of all soil types into four hydrologic groups. The derived CN largely mutes away original soil attribute details. A fuzzy approach refining CN according to soil hydrologic properties was developed to preserve d

Estimation of the cover and management factor for modeling soil erosion using remote sensing

The cover and management factor (C) of the Universal Soil Loss Equation (USLE) is difficult to be estimated over broad geographic areas where meteorology and soil erosion are poorly monitored. This paper presents a new approach to estimate C factor based on multi-temporal images of Landsat TM/ETM and a weather generator. The linear spectral unmixture algorithm was adopted to calculate the fraction

Application of SWAT for sediment yield estimation in a mountainous agricultural basin

The advanced SWAT (Soil and Water Assessment Tool) model is based on hydrologic process and needs to be calibrated and validated prior to application. This paper presents a case study conducted in Chaohe river upstream to verify the applicability of SWAT for predicting sediment yields in a semi-arid mountainous basin. Utilizing the gage records, the SWAT was deeply explored in the study area. The

Cardiovascular effects of severe late-onset preeclampsia are reversed within six months postpartum

OBJECTIVES: Preeclampsia (PE) is a common pregnancy-related disorder associated with cardiovascular long-term disease. Eighty percent are late-onset PE, occurring after 34 gestational weeks, and can present with severe symptoms. Magnitude and reversibility rate of maternal cardiovascular changes after severe late-onset PE have not been characterized. This study therefore evaluated longitudinal dyn

Expression of HIF-1α is related to a poor prognosis and tamoxifen resistance in contralateral breast cancer

Background: Adjuvant endocrine treatment improves survival after estrogen receptor (ER) positive breast cancer. Recurrences occur, and most patients with metastatic breast cancer develop treatment resistance and incurable disease. An influential factor in relation to endocrine treatment resistance is tumor hypoxia and the hypoxia inducible transcription factors (HIFs). Poor perfusion makes tumors