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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Short-term variations in ice dynamics during the spring and summer period on Storglaciären, Kebnekaise, Sweden.

Psaros, Helena January 2012 (has links)
Two Differential GPS (DGPS) stations were set up on Storglaciären in the upper and lower part of the ablation area to study short term variations of Storglaciären’s motion. The study period lasted from April to July 2009 and the DGPS logged data every second. Station 14, was situated over an overdeepening in the subglacial bedrock topography in the upper part of the ablation area, and was functioning the whole study period. Station 7, situated in the lower part of the ablation area, only lasted for nine days and only overlapped five days with station 14. There was a clear lag in ice motion between the two stations which indicates longitudinal coupling between the upper and the lower part of the ablation area. Station 14 pushed from up-glacier during the first acceleration event at the 24th of April and when the velocity decreased station 7 pulled from down-glacier.  The total movement of the DGPS station was 26 m during the study period. The velocity was well correlated to the external changes in temperature and precipitation. It appears to be eleven days lag in response time from April to middle of May, but after mid May the glacier responded directly to melt acts such as temperature changes and precipitation events. The delay most likely depended on the hydrological system was not entirely evolved during early spring. During the summer the system evolves which makes the glacier to respond directly to external changes. There were four major acceleration events during the study period and after the accelerations the velocity went back to the same low state as before. These cannot be interpreted as spring events as spring events should lead to an increase in the overall velocity. The temperature fluctuated during the whole study period which affects the melting rate and input and development of the hydrological system. To get a clear spring event a marked and substantial onset of melt season is needed. / Två differentiella bärvägs GPS (DGPS) stationer sattes upp på Storglaciären på den övre och lägre delen av ablations området för att studera korttidsvariationer i isflöde. Fältundersökningen pågick under april till juli 2009 och DGPS loggades varje sekund. Station 14 är placerad vid en överfördjupning i bottentopografin i den övre delen av ablationsområdet och var i gång under hela studien. Station 7 fungerade endast i nio dagar och är placerad vid den lägre delen av ablationsområdet samt överlappade under endast fem dagar med station 14. Det finns en tydlig fördröjning mellan de två stationerna i isrörelse vilket indikerar en longitudinell koppling mellan den övre och undre delen av ablationsområdet. Före den 24 april reagerade station 14 snabbare än station 7. Efter en kraftig acceleration vid station 14 den 24 april skedde det en förändring till att den nedre delen av ablationsområdet reagerade snabbare än den övre delen. Den totala förflyttningen av station 14 var 26 m under mätperioden. Hastigheten är korrelerad med externa förändringar i temperatur och nederbörd. Under april till mitten av maj var det en förändring i reaktionstid på elva dagar men den övergick under sommaren till att reagera direkt på förändringar i temperatur och nederbörd. Förskjutningen berodde troligtvis på att det hydrologiska systemet inte var tillräckligt utvecklat. Under sommaren utvecklas systemet vilket leder till att glaciären reagerar snabbare på externa förändringar. Det förekom fyra större accelerationshändelser under fältperioden. Efter de observerade accelerationerna gick hastigheten tillbaka till samma nivå. Dessa accelerationshändelser kan inte tolkas som våracceleration. En våracceleration innebär att den generella hastigheten hos glaciären ökar till en ny högre nivå. Detta kan bero på att temperaturen skiftade under hela fältperioden som styr smältning, isflöde och utveckling av det hydroligiska systemet. För att få en tydlig ”spring event” måste smältsäsongens nå en tydlig början och forstätta så kontinueligt.
2

Análise multifractal das correlações cruzadas entre séries temporais de precipitação e vazão

CHAGAS, Evelyn Souza 21 February 2014 (has links)
Submitted by (ana.araujo@ufrpe.br) on 2016-07-05T16:37:45Z No. of bitstreams: 1 Evelyn Souza Chagas.pdf: 2596910 bytes, checksum: 3edb34779be1962370072564bb024b44 (MD5) / Made available in DSpace on 2016-07-05T16:37:45Z (GMT). No. of bitstreams: 1 Evelyn Souza Chagas.pdf: 2596910 bytes, checksum: 3edb34779be1962370072564bb024b44 (MD5) Previous issue date: 2014-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Hydrological systems are composed of many components (precipitation, runoff, evaporation, transpiration, infiltration, etc.) and exhibit nonlinear behavior, with all individual components exhibiting non linear behavior as well. Although nonlinearity of hydrological processes has been recognized for many years, recent development of computational power and data acquisition technologies provide researches with powerful tools to evaluate existing methods and develop new more efficient techniques to study spatial and temporal variability and complexity of these phenomena. Considering that rainfall is the mayor natural factor that governs the stream flow regime, in this work we study non linear relationship between these components of the hydrological system, by examining multifractal correlations of individual rainfall and streamflow temporal series, as well as multifractal cross correlations between two processes. To this end we apply methods Multifractal Detrended Fluctuation Analysis (MF-DFA) and Multifractal Detrended Cross-Correlation Analysis (MF-DXA) on daily rainfall and streamflow temporal series registered in Piracicaba River Basin which is located in the state of São Paulo, Brazil. The results show that rainfall and streamflow temporal series exhibit multifractal correlations and cross correlations indicated by the generalized Hurst exponent, Renyi exponent and multifractal spectrum. The multifractal spectrum obtained by cross correlation analysis is similar to the multifractal spectrum of streamflow, for Corumbataí, Jaguari e Atibaia sub-basin, while for Camanducaia and Piracicaba sub-basin the cross correlation spectrum is more similar to the multifractal spectrum of precipitation. This difference could be related with land use and type of soil that affect the process of evapotranspiration and thus the whole hydrological cycle. / Sistemas hídricos são compostos por vários componentes (precipitação, escoamento, evaporação, transpiração, infiltração, etc) e exibem um comportamento não linear, com todos os componentes individuais exibindo um comportamento não linear também. Apesar da não linearidade dos processos hidrológicos ter sido reconhecida por muitos anos, o desenvolvimento recente do poder computacional e tecnologias de aquisição de dados proporcionam ferramentas poderosas para avaliar os métodos existentes e desenvolver novas técnicas mais eficientes para estudar a variabilidade espacial e temporal e a complexidade desses fenômenos. Considerando-se que a precipitação é o fator natural que mais influencia o regime de fluxo de vazão, neste trabalho estuda-se a relação não linear entre os componentes do sistema hidrológico, através da análise de correlações multifractais de séries temporais individuais de precipitação e vazão, assim como correlações cruzadas entre os dois processos. Para isto, são aplicados os métodos Multifractal Detrended Fluctuation Analysis (MF-DFA) e Multifractal Detrended Cross-Correlation Analysis (MF-DXA) em séries temporais diárias de precipitação e vazão registradas na Bacia do Rio Piracicaba, a qual está localizada no estado de São Paulo, Brasil. Os resultados mostram que séries temporais da precipitação e vazão possuem correlações e correlações cruzadas multifractais indicadas pelo comportamento das medidas multifractais: expoente de Hurst generalizado, expoente de Rényi e espectro multifractal. O espectro multifractal obtido pela análise de correlação cruzada (MF-DXA) é semelhante ao espectro multifractal da vazão (obtido pelo MF-DFA) para as sub-bacias Corumbataí, Jaguari e Atibaia, enquanto para as sub-bacias Camanducaia e Piracicaba a multifractalidade das correlações cruzadas é semelhante a multifractalidade da precipitação. Esta diferença poderia ser relacionada ao uso da terra e o tipo de solo que afeta o processo de evapotranspiração, e consequentemente todo o ciclo hidrológico da bacia.
3

Estudos hidrológicos como subsídio para a melhoria do acesso dos alunos do ensino fundamental às escolas ribeirinhas na bacia do Tarumã-mirim, Manaus/AM

Glória, Sidiney Araújo 21 May 2012 (has links)
Made available in DSpace on 2015-04-11T13:57:35Z (GMT). No. of bitstreams: 1 Sidiney.pdf: 7085701 bytes, checksum: 35554edcfc976bf002bc703f2ef449d6 (MD5) Previous issue date: 2012-05-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aims to raise hydrological subsidies to help improving access to educational units within the Tarumã-Mirim basin. This basin has seven public schools that provide a boat transportation service for their pupils. At times of the year, these vessels cannot enter the streams that make up the basin because of the hydrological variations. Thus, the schools and their social and educational aspects were identified. We sought to identify, using rainfall and gauge data, the months for which the access of teachers and students to these establishments is facilitated. Gauge and rain data were monitored on a daily basis at a hydrological station called Tarumã Mirim (ETM), created for this study at the school Raul Pompeia. The data from this station was compared to the data of the Rio Negro gauge at the port of Manaus. We analyzed the rainfall along with the stage levels within the basin and their influence on the local regime. The investigation of school transport routes and their variability within the hydrological cycle was apprehended via statistical means. The historical time series of the hydrological station at the port of Manaus was analyzed and correlated with the gauge data collected during the year 2011 at the ETM. The school transport routes were determined using GPS. Thus, it was possible to identify the layout of the trails traveled by boats during periods of high and low water. The data were plotted on the Geographic Information System (GIS) platform for thematic mapping. Based on the information obtained from this study, it was proposed to create subsidies for the development of an appropriate school calendar with respect to local hydrological regimes. / O presente estudo teve como propósito levantar subsídios hidrológicos, para auxiliar na melhoria do acesso às unidades educacionais no interior da bacia hidrográfica do Tarumã-Mirim, tal localidade dispõe de sete escolas municipais que utilizam transporte escolar náutico, em determinado período do ano estas embarcações são impedidas de adentrarem nos igarapés que compõe a bacia, devido às variações hidrológicas, para tanto, foram identificadas e localizadas as escolas, assim como, seus aspectos socioeducacionais. Buscou identificar por meio de estudos pluviométricos e fluviométricos os meses que facilitam o acesso dos docentes e discentes a estes educandários. Foram monitorados dados fluviométricos e pluviométricos diários em uma estação hidrológica denominada de Estação Tarumã Mirim (ETM), instalada para este estudo na escola Raul Pompeia, tal estação, forneceu dados para serem relacionados com os dados de cota do Rio Negro, registrados na estação do porto de Manaus, analisou-se a pluviosidade juntamente com o nível de cota no interior da bacia e a influência registrada no regime local. Realizaram-se análises das rotas do transporte escolar e suas variabilidades dentro do ciclo hidrológico, recorreram-se aos meios estatísticos para analisar e correlacionar dos dados de séries históricas das estações hidrológicas do porto de Manaus, com os dados fluviométricos coletados durante o ano de 2011 na ETM. As rotas do transporte escolar foram realizadas com auxílio de GPS para identificar o traçado das trilhas percorridas pelas lanchas nos períodos de águas altas e águas baixas. Os dados foram plotados em plataforma do Sistema de Informações Geográfica (SIG) para elaboração de mapas temáticos. Com base nas informações obtidas no estudo, criaram-se subsídios para propor a elaboração de um calendário escolar adequado aos regimes hidrológicos locais.
4

Application of integrated water resources management in computer simulation of River Basin's status - case study of River Rwizi

Atim, Janet 06 1900 (has links)
Thesis (M. Tech. - (Civil Engineering, Faculty of Engineering and Technology))--Vaal University of Technology, 2010. / During the last few years, concern has been growing among many stakeholders all over the world about declining levels of surface water bodies accompanied by reduced water availability predominantly due to ever increasing demand and misuse. Furthermore, overexploitation of environmental resources and haphazard dumping of waste has made the little water remaining to be so contaminated that a dedicated rehabilitation/remediation of the environment is the only proactive way forward. River Rwizi Catchment is an environment in the focus of this statement. The overall objective of this research was to plan, restore and rationally allocate the water resources in any river basin with similar attributes to the study area. In this research, Integrated Water Resources Management (IWRM) methodology was applied through Watershed/Basin Simulation Models for general river basins. The model chosen and used after subjection to several criteria was DHI Model, MIKE BASIN 2009 Version. It was then appropriately developed through calibration on data from the study catchment, input data formatting and its adaptation to the catchment characteristics. The methodology involved using spatio-temporal demographic and hydrometeorological data. It was established that the model can be used to predict the impact of projects on the already existing enviro-hydrological system while assigning priority to water users and usage as would be deemed necessary, which is a significant procedure in IWRM-based environmental rehabilitation/remediation. The setback was that the available records from the various offices visited had a lot of data gaps that would affect the degree of accuracy of the output. These gaps were appropriately infilled and gave an overall output that was adequate for inferences made therefrom. Several scenarios tested included; use and abstraction for the present river situation, the effect of wet/dry seasons on the resultant water available for use, and proposed projects being constructed on and along the river. Results indicated that the river had insufficient flow to sustain both the current and proposed water users. It was concluded that irrespective of over exploitation, lack of adequate rainfall was not a reason for the low discharge but rather the loss of rainwater as evaporation, storage in swamps/wetlands, and a considerable amount of water recharging groundwater aquifers. Thus, the proposed remedy is to increase the exploitation of the groundwater resource in the area and reduce the number of direct river water users, improve farming methods and conjunctive use of groundwater and surface water - the latter as a dam on River Rwizi. The advantage of the dam is that the water usage can be controlled as necessary in contrast to unregulated direct abstraction, thus reducing the risk of subsequent over-exploitation. / Vaal University of Technology
5

Itinerário de uma transformação paisagística urbana. O Parque Terceiro Milênio e a estrutura ecológica urbana na cidade de Bogotá DC - Colombia / A journey of transforming urban landscape. Third Millennium Park and the ecological and urban structure in Bogota DC - Colombia

Dueñas Pinto, Nelson Domingo 14 October 2009 (has links)
A partir do ano 2000 cunhou-se no discurso do Ordenamento Territorial de Bogotá D.C. o conceito de Estrutura Ecológica, o qual foi interpretado como uma categoria fundamental no ordenamento espacial do território, com uma função específica: manter e conduzir a biodiversidade e os processos ecológicos essenciais do território. Os parques urbanos de grande escala que até antes desse ano eram visualizados como peças isoladas na superfície urbana, destinadas à recreação dos cidadãos incorporaram-se como um sistema essencial no ordenamento do território por meio deste conceito de Estrutura Ecológica; em consequência, a noção de parque urbano de grande escala ou metropolitano adquiriu um compromisso ambiental, que até os dias de hoje não tinha sido plenamente reconhecido. Neste contexto enquadra-se o Parque Metropolitano Terceiro Milênio, o qual foi concebido como uma obra de renovação urbana no setor de maior deterioramento físico, social e ambiental do centro da cidade, e foi estabelecido sobre o curso e ponto de confluência dos rios San Francisco e San Agustín, corpos de água de grande importância desde a fundação da cidade. Devido ao propósito com o qual foi concebido o projeto e a sua estratégica localização como parte integrante da Estrutura Ecológica de Bogotá, o Parque Terceiro Milênio foi uma grande oportunidade de contribuir para o melhoramento das condições do ecossistema da cidade, a recuperação do sistema hídrico natural, a renaturalização da rede de Corredores Ecológicos e a transformação da paisagem do centro de Bogotá. A simultaneidade de propósitos que convergiram na concepção, formulação e materialização deste Parque é exatamente o ponto de partida que motivou a pesquisa presente nesta dissertação. O Parque Terceiro Milênio reúne condições que o tornam uma oportunidade para a reflexão sobre os vínculos e as possíveis contradições que existem entre o discurso ambiental representado no conceito de Estrutura Ecológica e a formulação e materialização de um projeto concreto. É assim que a metodologia privilegia: uma análise do ideário presente nos documentos de formulação do projeto, para o qual se desenvolve uma leitura crítica do conceito de Estrutura Ecológica; uma avaliação em perspectiva histórica e em diferentes escalas, da forma como a cidade ocupou seu território; um exame dos estudos e desenhos dos três projetos que configuraram o ideário do Parque e sua relação com a Estrutura Ecológica; e uma análise integral da relação entre o parque e sua bacia hidrográfica. O desenvolvimento da pesquisa permitiu estabelecer, entre outros aspectos, a existência de uma fratura entre o discurso ambiental e o projeto executado, sendo pertinente à academia e à administração distrital lançarem um olhar mais amplo qualitativa e quantitativa sobre o sistema hídrico da cidade e, finalmente, sendo necessário implementar novas metodologias e elementos de análise que ressarçam as deficiências que se apresentaram na formulação e construção de projetos urbanos pertencentes à estrutura ecológica, como foi o caso do Parque Terceiro Milênio. / Since 2000 the concept of Ecologic Structure has been incorporated as part of the territorial reorganization of Bogota D.C., and is being interpreted as a fundamental category in the spatial reorganization of the territory, with a specific function: sustain and drive the biodiversity and the territorys essential ecological processes. The large scale urban parks which until that year were visualized as separated pieces in the urban landscape providing recreation to inhabitants- were incorporated as an essential system in the territorys order thru the concept of Ecological Structure; as such, the metropolitan urban park or large scale park acquired an environmental compromise that until then was not recognized. Under this context, the Third Millennium Metropolitan Park (2000-2005) was conceived as a piece of urban renovation in the area of the city presenting the most physical, social and environmental detriment in the downtown core and it was located where the rivers San Francisco and San Agustín meet. It should be noted that these two Rivers have been water bodies of great importance since the foundation of the city. Given the purpose of the project and its strategic location as an integral part of the Ecological Structure of Bogota, the Third Millennium Park was visualized as a great opportunity to contribute to the improvement of the citys ecosystem, the recovery of the natural hydrological system, the re-naturalization of the network of ecological corridors and the transformation of the downtowns landscape. The way of these diverse purposes came together during the conception, proposal and implementation of this park is precisely the starting point for this investigation. The Third Millennium Park meets the conditions that turn it into an opportunity to reflect about the linkages and potential contradictions that exist between the environmental speech represented by the concept of ecological structure- and the proposal and implementation of a concrete project. This is how the methodology benefits an analysis of the thoughts and ideas contained in the proposal documents of the project. For this reason the following actions are being conducted: a critical analysis of the Ecological Structure concept; an evaluation of how the city occupied its territory from a historical and scale perspective; research of the designs and studies of the three projects that conformed the conceptualization of the park and its relationship with the Ecological Structure; and a thorough analysis of the relationship between the park and the watershed. This research established among other aspects that there is a disconnect between the environmental speech and the implemented project, that it is pertinent that the scholars and the municipal administration perform a more comprehensive analysis quantitative and qualitative- about the hydrological system of the city, and lastly, that it is necessary implementing new methodologies and analysis elements to correct the deficiencies that were found in the proposal and construction of urban projects belonging to the ecological structure, as it was the case with the Third Millennium Park.
6

Itinerário de uma transformação paisagística urbana. O Parque Terceiro Milênio e a estrutura ecológica urbana na cidade de Bogotá DC - Colombia / A journey of transforming urban landscape. Third Millennium Park and the ecological and urban structure in Bogota DC - Colombia

Nelson Domingo Dueñas Pinto 14 October 2009 (has links)
A partir do ano 2000 cunhou-se no discurso do Ordenamento Territorial de Bogotá D.C. o conceito de Estrutura Ecológica, o qual foi interpretado como uma categoria fundamental no ordenamento espacial do território, com uma função específica: manter e conduzir a biodiversidade e os processos ecológicos essenciais do território. Os parques urbanos de grande escala que até antes desse ano eram visualizados como peças isoladas na superfície urbana, destinadas à recreação dos cidadãos incorporaram-se como um sistema essencial no ordenamento do território por meio deste conceito de Estrutura Ecológica; em consequência, a noção de parque urbano de grande escala ou metropolitano adquiriu um compromisso ambiental, que até os dias de hoje não tinha sido plenamente reconhecido. Neste contexto enquadra-se o Parque Metropolitano Terceiro Milênio, o qual foi concebido como uma obra de renovação urbana no setor de maior deterioramento físico, social e ambiental do centro da cidade, e foi estabelecido sobre o curso e ponto de confluência dos rios San Francisco e San Agustín, corpos de água de grande importância desde a fundação da cidade. Devido ao propósito com o qual foi concebido o projeto e a sua estratégica localização como parte integrante da Estrutura Ecológica de Bogotá, o Parque Terceiro Milênio foi uma grande oportunidade de contribuir para o melhoramento das condições do ecossistema da cidade, a recuperação do sistema hídrico natural, a renaturalização da rede de Corredores Ecológicos e a transformação da paisagem do centro de Bogotá. A simultaneidade de propósitos que convergiram na concepção, formulação e materialização deste Parque é exatamente o ponto de partida que motivou a pesquisa presente nesta dissertação. O Parque Terceiro Milênio reúne condições que o tornam uma oportunidade para a reflexão sobre os vínculos e as possíveis contradições que existem entre o discurso ambiental representado no conceito de Estrutura Ecológica e a formulação e materialização de um projeto concreto. É assim que a metodologia privilegia: uma análise do ideário presente nos documentos de formulação do projeto, para o qual se desenvolve uma leitura crítica do conceito de Estrutura Ecológica; uma avaliação em perspectiva histórica e em diferentes escalas, da forma como a cidade ocupou seu território; um exame dos estudos e desenhos dos três projetos que configuraram o ideário do Parque e sua relação com a Estrutura Ecológica; e uma análise integral da relação entre o parque e sua bacia hidrográfica. O desenvolvimento da pesquisa permitiu estabelecer, entre outros aspectos, a existência de uma fratura entre o discurso ambiental e o projeto executado, sendo pertinente à academia e à administração distrital lançarem um olhar mais amplo qualitativa e quantitativa sobre o sistema hídrico da cidade e, finalmente, sendo necessário implementar novas metodologias e elementos de análise que ressarçam as deficiências que se apresentaram na formulação e construção de projetos urbanos pertencentes à estrutura ecológica, como foi o caso do Parque Terceiro Milênio. / Since 2000 the concept of Ecologic Structure has been incorporated as part of the territorial reorganization of Bogota D.C., and is being interpreted as a fundamental category in the spatial reorganization of the territory, with a specific function: sustain and drive the biodiversity and the territorys essential ecological processes. The large scale urban parks which until that year were visualized as separated pieces in the urban landscape providing recreation to inhabitants- were incorporated as an essential system in the territorys order thru the concept of Ecological Structure; as such, the metropolitan urban park or large scale park acquired an environmental compromise that until then was not recognized. Under this context, the Third Millennium Metropolitan Park (2000-2005) was conceived as a piece of urban renovation in the area of the city presenting the most physical, social and environmental detriment in the downtown core and it was located where the rivers San Francisco and San Agustín meet. It should be noted that these two Rivers have been water bodies of great importance since the foundation of the city. Given the purpose of the project and its strategic location as an integral part of the Ecological Structure of Bogota, the Third Millennium Park was visualized as a great opportunity to contribute to the improvement of the citys ecosystem, the recovery of the natural hydrological system, the re-naturalization of the network of ecological corridors and the transformation of the downtowns landscape. The way of these diverse purposes came together during the conception, proposal and implementation of this park is precisely the starting point for this investigation. The Third Millennium Park meets the conditions that turn it into an opportunity to reflect about the linkages and potential contradictions that exist between the environmental speech represented by the concept of ecological structure- and the proposal and implementation of a concrete project. This is how the methodology benefits an analysis of the thoughts and ideas contained in the proposal documents of the project. For this reason the following actions are being conducted: a critical analysis of the Ecological Structure concept; an evaluation of how the city occupied its territory from a historical and scale perspective; research of the designs and studies of the three projects that conformed the conceptualization of the park and its relationship with the Ecological Structure; and a thorough analysis of the relationship between the park and the watershed. This research established among other aspects that there is a disconnect between the environmental speech and the implemented project, that it is pertinent that the scholars and the municipal administration perform a more comprehensive analysis quantitative and qualitative- about the hydrological system of the city, and lastly, that it is necessary implementing new methodologies and analysis elements to correct the deficiencies that were found in the proposal and construction of urban projects belonging to the ecological structure, as it was the case with the Third Millennium Park.
7

Scaling methods of leakage correction in GRACE mass change estimates revisited for the complex hydro-climatic setting of the Indus Basin

Tripathi, Vasaw, Groh, Andreas, Horwath, Martin, Ramsankaran, Raaj 18 April 2024 (has links)
Total water storage change (TWSC) reflects the balance of all water fluxes in a hydrological system. The Gravity Recovery and Climate Experiment/Follow-On (GRACE/GRACE-FO) monthly gravity field models, distributed as spherical harmonic (SH) coefficients, are the only means of observing this state variable. The well-known correlated noise in these observations requires filtering, which scatters the actual mass changes from their true locations. This effect is known as leakage. This study explores the traditional basin and grid scaling approaches, and develops a novel frequency-dependent scaling for leakage correction of GRACE TWSC in a unique, basin-specific assessment for the Indus Basin. We harness the characteristics of significant heterogeneity in the Indus Basin due to climate and human-induced changes to study the physical nature of these scaling schemes. The most recent WaterGAP (Water Global Assessment and Prognosis) hydrology model (WGHM v2.2d) with its two variants, standard (without glacier mass changes) and Integrated (with glacier mass changes), is used to derive scaling factors. For the first time, we explicitly show the effect of inclusion or exclusion of glacier mass changes in the model on the gridded scaling factors. The inferences were validated in a detailed simulation environment designed using WGHM fields corrupted with GRACE-like errors using full monthly error covariance matrices. We find that frequency-dependent scaling outperforms both basin and grid scaling for the Indus Basin, where mass changes of different frequencies are localized. Grid scaling can resolve trends from glacier mass loss and groundwater loss but fails to recover the small seasonal signals in trunk Indus. Frequency-dependent scaling can provide a robust estimate of the seasonal cycle of TWSC for practical applications such as regional-scale water availability assessments. Apart from these novel developments and insights into the traditional scaling approach, our study encourages the regional scale users to conduct specific assessments for their basin of interest.

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