Search results

Filter

Filetype

Your search for "*" yielded 528238 hits

Monitoring ice variations in Qinghai Lake from 1979 to 2016 using passive microwave remote sensing data

Lake ice is a sensitive indicator of climate change. Based on the disparities between the brightness temperatures of lake ice and water, passive microwave data can be used to monitor the ice variations of a lake. With focus on the analysis of long time series variability of lake ice, this study extracts four characteristic dates related to lake ice (the annual freeze start, freeze completion, abla

Characterization of droughts during 2001–2014 based on remote sensing : A case study of Northeast China

Northeast China, the most important region for commercial grain farming in China, is vulnerable to drought due to high fluctuation in monthly rainfall. Timely, accurate and effective drought monitoring is very essential for securing the output of grain farming. In this study, three widely used drought indices were compared using satellite soil moisture data and their capability for drought monitor

Evaluation of three energy balance-based evaporation models for estimating monthly evaporation for five lakes using derived heat storage changes from a hysteresis model

The heat storage changes (Q t) can be a significant component of the energy balance in lakes, and it is important to account for Q t for reasonable estimation of evaporation at monthly and finer timescales if the energy balance-based evaporation models are used. However, Q t has been often neglected in many studies due to the lack of required water temperature data. A simple hysteresis model (Q t

Evaluation of precipitation input for SWAT modeling in Alpine catchment : A case study in the Adige river basin (Italy)

Precipitation is often the most important input data in hydrological models when simulating streamflow. The Soil and Water Assessment Tool (SWAT), a widely used hydrological model, only makes use of data from one precipitation gauge station that is nearest to the centroid of each subbasin, which is eventually corrected using the elevation band method. This leads in general to inaccurate representa

Evaluation of eight high spatial resolution gridded precipitation products in Adige Basin (Italy) at multiple temporal and spatial scales

This study provides a comprehensive evaluation of eight high spatial resolution gridded precipitation products in Adige Basin located in Italy within 45–47.1°N. The Adige Basin is characterized by a complex topography, and independent ground data are available from a network of 101 rain gauges during 2000–2010. The eight products include the Version 7 TRMM (Tropical Rainfall Measuring Mission) Mul

The environmental sustainability of nations : Benchmarking the carbon, water and land footprints against allocated planetary boundaries

Growing scientific evidence for the indispensable role of environmental sustainability in sustainable development calls for appropriate frameworks and indicators for environmental sustainability assessment (ESA). In this paper, we operationalize and update the footprint-boundary ESA framework, with a particular focus on its methodological and application extensions to the national level. By using

Comparison of four algorithms to retrieve land surface temperature using Landsat 8 satellite

Land Surface Temperature (LST) plays an important role in energy exchange between the land surface and the atmosphere. LST is a key variable in many applications, such as land surface modeling. Many satellite-based algorithms have been proposed to retrieve LST, such as Split-Window (SW), dual-angle, and single-channel algorithms. In this study, four satellite-based LST retrieval algorithms, includ

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

No title

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