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Sujay V Kumar - One of the best experts on this subject based on the ideXlab platform.
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modeling regional pollution transport events during korus aq progress and challenges in improving representation of Land atmosphere feedbacks
Journal of Geophysical Research, 2018Co-Authors: Min Huang, Sujay V Kumar, J H Crawford, Glenn S Diskin, Joseph A Santanello, S E Pusede, Mark Parrington, Gregory R CarmichaelAbstract:This study evaluates the impact of assimilating soil moisture data from NASA's Soil Moisture Active Passive (SMAP) on short-term regional weather and air quality modeling in East Asia during the Korea-US Air Quality Study (KORUS-AQ) airborne campaign. SMAP data are assimilated into the Noah Land surface model using an ensemble Kalman filter approach in the Land Information System framework, which is semi-coupled with the NASA-Unified Weather Research and Forecasting model with online chemistry (NUWRF-Chem). With SMAP assimilation included, water vapor and carbon monoxide (CO) transport from northern-central China transitional climate zones to South Korea is better represented in NUWRF-Chem during two studied pollution events. Influenced by different synoptic conditions and emission patterns, impact of SMAP assimilation on modeled CO in South Korea is intense (>30 ppbv) during one event and less significant (<8 ppbv) during the other. SMAP assimilation impact on air quality modeling skill is complicated by other error sources such as the chemical initial and boundary conditions (IC/LBC) and emission inputs of NUWRF-Chem. Using a satellite-observation-constrained chemical IC/LBC instead of a free-running, coarser-resolution chemical IC/LBC reduces modeled CO by up to 80 ppbv over South Korea. Consequently, CO performance is improved in the middle-upper troposphere whereas degraded in the lower troposphere. Remaining negative CO biases result largely from the emissions inputs. The advancements in Land surface modeling and chemical IC/LBC presented here are expected to benefit future investigations on constraining emissions using observations, which can in turn enable more accurate assessments of SMAP assimilation and chemical IC/LBC impacts.
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a Land data assimilation System for sub saharan africa food and water security applications
Scientific Data, 2017Co-Authors: Sujay V Kumar, Amy Mcnally, Kristi R Arsenault, Shraddhanand Shukla, Pete Peterson, Shugong Wang, Chris FunkAbstract:Seasonal agricultural drought monitoring Systems, which rely on satellite remote sensing and Land surface models (LSMs), are important for disaster risk reduction and famine early warning. These Systems require the best available weather inputs, as well as a long-term historical record to contextualize current observations. This article introduces the Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation System (FLDAS), a custom instance of the NASA Land Information System (LIS) framework. The FLDAS is routinely used to produce multi-model and multi-forcing estimates of hydro-climate states and fluxes over semi-arid, food insecure regions of Africa. These modeled data and derived products, like soil moisture percentiles and water availability, were designed and are currently used to complement FEWS NET’s operational remotely sensed rainfall, evapotranspiration, and vegetation observations. The 30+ years of monthly outputs from the FLDAS simulations are publicly available from the NASA Goddard Earth Science Data and Information Services Center (GES DISC) and recommended for use in hydroclimate studies, early warning applications, and by agro-meteorological scientists in Eastern, Southern, and Western Africa. Machine-accessible metadata file describing the reported data (ISA-Tab format)
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A Land data assimilation System for sub-Saharan Africa food and water security applications
Scientific Data, 2017Co-Authors: Amy Mcnally, Sujay V Kumar, Kristi R Arsenault, Shraddhanand Shukla, Pete Peterson, Shugong Wang, Chris Funk, Christa D. Peters-lidard, James P. VerdinAbstract:Seasonal agricultural drought monitoring Systems, which rely on satellite remote sensing and Land surface models (LSMs), are important for disaster risk reduction and famine early warning. These Systems require the best available weather inputs, as well as a long-term historical record to contextualize current observations. This article introduces the Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation System (FLDAS), a custom instance of the NASA Land Information System (LIS) framework. The FLDAS is routinely used to produce multi-model and multi-forcing estimates of hydro-climate states and fluxes over semi-arid, food insecure regions of Africa. These modeled data and derived products, like soil moisture percentiles and water availability, were designed and are currently used to complement FEWS NET’s operational remotely sensed rainfall, evapotranspiration, and vegetation observations. The 30+ years of monthly outputs from the FLDAS simulations are publicly available from the NASA Goddard Earth Science Data and Information Services Center (GES DISC) and recommended for use in hydroclimate studies, early warning applications, and by agro-meteorological scientists in Eastern, Southern, and Western Africa. Machine-accessible metadata file describing the reported data (ISA-Tab format)
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the nasa goddard multi scale modeling framework Land Information System global Land atmosphere interaction with resolved convection
Environmental Modelling and Software, 2013Co-Authors: Karen I Mohr, Sujay V Kumar, Weikuo Tao, Jiundar Chern, Christa D PeterslidardAbstract:The present generation of general circulation models (GCM) use parameterized cumulus schemes and run at hydrostatic grid resolutions. To improve the representation of cloud-scale moist processes and Land-atmosphere interactions, a global, Multi-scale Modeling Framework (MMF) coupled to the Land Information System (LIS) has been developed at NASA-Goddard Space Flight Center. The MMF-LIS has three components, a finite-volume (fv) GCM (Goddard Earth Observing System Ver. 4, GEOS-4), a 2D cloud-resolving model (Goddard Cumulus Ensemble, GCE), and the LIS, representing the large-scale atmospheric circulation, cloud processes, and Land surface processes, respectively. The non-hydrostatic GCE model replaces the single-column cumulus parameterization of fvGCM. The model grid is composed of an array of fvGCM gridcells each with a series of embedded GCE models. A horizontal coupling strategy, GCE @? fvGCM @? Coupler @? LIS, offered significant computational efficiency, with the scalability and I/O capabilities of LIS permitting Land-atmosphere interactions at cloud-scale. Global simulations of 2007-2008 and comparisons to observations and reanalysis products were conducted. Using two different versions of the same Land surface model but the same initial conditions, divergence in regional, synoptic-scale surface pressure patterns emerged within two weeks. The sensitivity of large-scale circulations to Land surface model physics revealed significant functional value to using a scalable, multi-model Land surface modeling System in global weather and climate prediction.
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improving numerical weather predictions of summertime precipitation over the southeastern united states through a high resolution initialization of the surface state
Weather and Forecasting, 2011Co-Authors: Jonathan L Case, Sujay V Kumar, Jayanthi Srikishen, Gary J JedlovecAbstract:AbstractIt is hypothesized that high-resolution, accurate representations of surface properties such as soil moisture and sea surface temperature are necessary to improve simulations of summertime pulse-type convective precipitation in high-resolution models. This paper presents model verification results of a case study period from June to August 2008 over the southeastern United States using the Weather Research and Forecasting numerical weather prediction model. Experimental simulations initialized with high-resolution Land surface fields from the National Aeronautics and Space Administration’s (NASA) Land Information System (LIS) and sea surface temperatures (SSTs) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) are compared to a set of control simulations initialized with interpolated fields from the National Centers for Environmental Prediction’s (NCEP) 12-km North American Mesoscale model. The LIS Land surface and MODIS SSTs provide a more detailed surface initialization at a...
Christa D Peterslidard - One of the best experts on this subject based on the ideXlab platform.
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the nasa goddard multi scale modeling framework Land Information System global Land atmosphere interaction with resolved convection
Environmental Modelling and Software, 2013Co-Authors: Karen I Mohr, Sujay V Kumar, Weikuo Tao, Jiundar Chern, Christa D PeterslidardAbstract:The present generation of general circulation models (GCM) use parameterized cumulus schemes and run at hydrostatic grid resolutions. To improve the representation of cloud-scale moist processes and Land-atmosphere interactions, a global, Multi-scale Modeling Framework (MMF) coupled to the Land Information System (LIS) has been developed at NASA-Goddard Space Flight Center. The MMF-LIS has three components, a finite-volume (fv) GCM (Goddard Earth Observing System Ver. 4, GEOS-4), a 2D cloud-resolving model (Goddard Cumulus Ensemble, GCE), and the LIS, representing the large-scale atmospheric circulation, cloud processes, and Land surface processes, respectively. The non-hydrostatic GCE model replaces the single-column cumulus parameterization of fvGCM. The model grid is composed of an array of fvGCM gridcells each with a series of embedded GCE models. A horizontal coupling strategy, GCE @? fvGCM @? Coupler @? LIS, offered significant computational efficiency, with the scalability and I/O capabilities of LIS permitting Land-atmosphere interactions at cloud-scale. Global simulations of 2007-2008 and comparisons to observations and reanalysis products were conducted. Using two different versions of the same Land surface model but the same initial conditions, divergence in regional, synoptic-scale surface pressure patterns emerged within two weeks. The sensitivity of large-scale circulations to Land surface model physics revealed significant functional value to using a scalable, multi-model Land surface modeling System in global weather and climate prediction.
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diagnosing the sensitivity of local Land atmosphere coupling via the soil moisture boundary layer interaction
Journal of Hydrometeorology, 2011Co-Authors: Joseph A Santanello, Christa D Peterslidard, Sujay V KumarAbstract:AbstractThe inherent coupled nature of earth’s energy and water cycles places significant importance on the proper representation and diagnosis of Land–atmosphere (LA) interactions in hydrometeorological prediction models. However, the precise nature of the soil moisture–precipitation relationship at the local scale is largely determined by a series of nonlinear processes and feedbacks that are difficult to quantify. To quantify the strength of the local LA coupling (LoCo), this process chain must be considered both in full and as individual components through their relationships and sensitivities. To address this, recent modeling and diagnostic studies have been extended to 1) quantify the processes governing LoCo utilizing the thermodynamic properties of mixing diagrams, and 2) diagnose the sensitivity of coupled Systems, including clouds and moist processes, to perturbations in soil moisture. This work employs NASA’s Land Information System (LIS) coupled to the Weather Research and Forecasting (WRF) me...
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a Land surface data assimilation framework using the Land Information System description and applications
Advances in Water Resources, 2008Co-Authors: Sujay V Kumar, Christa D Peterslidard, Rolf H Reichle, Randal D Koster, Xiwu Zhan, Wade T Crow, John B Eylander, Paul R HouserAbstract:The Land Information System (LIS) is an established Land surface modeling framework that integrates various community Land surface models, ground measurements, satellite-based observations, high performance computing and data management tools. The use of advanced software engineering principles in LIS allows interoperability of individual System components and thus enables assessment and prediction of hydrologic conditions at various spatial and temporal scales. In this work, we describe a sequential data assimilation extension of LIS that incorporates multiple observational sources, Land surface models and assimilation algorithms. These capabilities are demonstrated here in a suite of experiments that use the ensemble Kalman filter (EnKF) and assimilation through direct insertion. In a soil moisture experiment, we discuss the impact of differences in modeling approaches on assimilation performance. Provided careful choice of model error parameters, we find that two entirely different hydrological modeling approaches offer comparable assimilation results. In a snow assimilation experiment, we investigate the relative merits of assimilating different types of observations (snow cover area and snow water equivalent). The experiments show that data assimilation enhancements in LIS are uniquely suited to compare the assimilation of various data types into different Land surface models within a single framework. The high performance infrastructure provides adequate support for efficient data assimilation integrations of high computational granularity.
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high performance earth System modeling with nasa gsfc s Land Information System
Innovations in Systems and Software Engineering, 2007Co-Authors: Christa D Peterslidard, Sujay V Kumar, Paul R Houser, S Olden, L Lighty, B Doty, J. Geiger, Paul A. Dirmeyer, Yudong Tian, Jennifer M AdamsAbstract:The Land Information System software (LIS; http://lis.gsfc.nasa.gov/, 2006) has been developed to support high-performance Land surface modeling and data assimilation. LIS integrates parallel and distributed computing technologies with modern Land surface modeling capabilities, and establishes a framework for easy interchange of subcomponents, such as Land surface physics, input/output conventions, and data assimilation routines. The software includes multiple Land surface models that can be run as a multi-model ensemble on global or regional domains with horizontal resolutions ranging from 2.5° to 1 km. The software may execute serially or in parallel on various high-performance computing platforms. In addition, the software has well-defined, standard-conforming interfaces and data structures to interface and interoperate with other Earth System models. Developed with the support of an Earth science technology office (ESTO) computational technologies project round~3 cooperative agreement, LIS has helped advance NASA’s Earth–Sun division’s software engineering principles and practices, while promoting portability, interoperability, and scalability for Earth System modeling. LIS was selected as a co-winner of NASA’s 2005 software of the year award.
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a gis framework for surface layer soil moisture estimation combining satellite radar measurements and Land surface modeling with soil physical property estimation
Environmental Modelling and Software, 2007Co-Authors: Michael A Tischler, Sujay V Kumar, Christa D Peterslidard, Matthew Garcia, M S Moran, Scott N Miller, David P Thoma, J. GeigerAbstract:A GIS framework, the Army Remote Moisture System (ARMS), has been developed to link the Land Information System (LIS), a high performance Land surface modeling and data assimilation System, with remotely sensed measurements of soil moisture to provide a high resolution estimation of soil moisture in the near surface. ARMS uses available soil (soil texture, porosity, K"s"a"t), Land cover (vegetation type, LAI, Fraction of Greenness), and atmospheric data (Albedo) in standardized vector and raster GIS data formats at multiple scales, in addition to climatological forcing data and precipitation. PEST (Parameter EStimation Tool) was integrated into the process to optimize soil porosity and saturated hydraulic conductivity (K"s"a"t), using the remotely sensed measurements, in order to provide a more accurate estimate of the soil moisture. The modeling process is controlled by the user through a graphical interface developed as part of the ArcMap component of ESRI ArcGIS.
Christian Lemmen - One of the best experts on this subject based on the ideXlab platform.
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the Land administration domain model ladm as the reference model for the cyprus Land Information System clis
Survey Review, 2013Co-Authors: E Elia, J A Zevenbergen, Christian LemmenAbstract:In this paper, the enhancement of the data model of the Cyprus Land Information System (CLIS), with the adoption of the Land administration domain model (LADM) is examined. The CLIS was established in 1999, within the Department of Lands and Surveys, to support the operation of the Cyprus cadastral System and has met the majority of its initial set goals. It is however now broadly accepted that the CLIS should be improved and upgraded, and a new data model should be introduced to facilitate the manipulation and provision of data to internal and external users/ customers in a more effective way. The need to enhance the CLIS coincides with the introduction of the LADM, which is under development within the Technical Committee 211 of the International Organization for Standardization and identified as ISO 19152. The LADM provides an abstract, conceptual schema with three basic packages: parties (such as people and organisations), administrative rights, responsibilities and restrictions (such as property rights) and spatial units (such as parcels, buildings and networks), with the latter having one subpackage: surveying and spatial representation [6]. [Note: In this moment (January 2012), the LADM is at the development stage of Final Draft International Standard]. In this paper, the basic entities of the CLIS are presented and restructured, in a way to comply with the LADM. After analysing the characteristics of LADM, it is concluded that this is compatible with CLIS, and can be used as a data model framework for CLIS’s upgrade. Thus, the Cyprus country profile is proposed. The adoption of the LADM is a great opportunity for the Department of Lands and Surveys to introduce an International Organization for Standardization standard model, based on model driven architecture, and to gain all the benefits derived from such a movement. Such benefits include the improvement in the effectiveness and the efficiency of the current System and the expansion of the services provided by CLIS to the broader Land administration System and to the Cyprus community. The new functionality includes: better structuring of the rights, responsibilities and restrictions (and related source documents); better fitting in the Information infrastructure, both national (e.g. valuation, taxation, building, address and person registrations) and international (e.g. INSPIRE cadastral parcels); and future capabilities for representing three-dimensional spatial units (e.g. legal spaces related to apartment or utility infrastructure).
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the Land administration domain model ladm as the reference model for the cyprus Land Information System clis
Bridging the Gap between Cultures FIG Working Week 2001 Marrakech Morocco 18-22 May 2011 TS02C-Spatial Data Infrastructures paper 4880, 2011Co-Authors: E Elia, Christian Lemmen, J A Zevenbergen, P J M Van OosteromAbstract:In this paper the enhancement of the data model of the Cyprus Land Information System (CLIS), with the adoption of the Land Administration Domain Model (LADM) is examined. The Cyprus Land Information System (CLIS), was established in 1999, within the Department of Lands and Surveys (DLS), to support the operation of the Cyprus cadastral System and has met the majority of its initial set goals. It is however now broadly accepted that the CLIS should be improved and upgraded, and a new data model should be introduced to facilitate the manipulation and provision of data to internal and external users/customers in a more effective way.
Amy Mcnally - One of the best experts on this subject based on the ideXlab platform.
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a Land data assimilation System for sub saharan africa food and water security applications
Scientific Data, 2017Co-Authors: Sujay V Kumar, Amy Mcnally, Kristi R Arsenault, Shraddhanand Shukla, Pete Peterson, Shugong Wang, Chris FunkAbstract:Seasonal agricultural drought monitoring Systems, which rely on satellite remote sensing and Land surface models (LSMs), are important for disaster risk reduction and famine early warning. These Systems require the best available weather inputs, as well as a long-term historical record to contextualize current observations. This article introduces the Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation System (FLDAS), a custom instance of the NASA Land Information System (LIS) framework. The FLDAS is routinely used to produce multi-model and multi-forcing estimates of hydro-climate states and fluxes over semi-arid, food insecure regions of Africa. These modeled data and derived products, like soil moisture percentiles and water availability, were designed and are currently used to complement FEWS NET’s operational remotely sensed rainfall, evapotranspiration, and vegetation observations. The 30+ years of monthly outputs from the FLDAS simulations are publicly available from the NASA Goddard Earth Science Data and Information Services Center (GES DISC) and recommended for use in hydroclimate studies, early warning applications, and by agro-meteorological scientists in Eastern, Southern, and Western Africa. Machine-accessible metadata file describing the reported data (ISA-Tab format)
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A Land data assimilation System for sub-Saharan Africa food and water security applications
Scientific Data, 2017Co-Authors: Amy Mcnally, Sujay V Kumar, Kristi R Arsenault, Shraddhanand Shukla, Pete Peterson, Shugong Wang, Chris Funk, Christa D. Peters-lidard, James P. VerdinAbstract:Seasonal agricultural drought monitoring Systems, which rely on satellite remote sensing and Land surface models (LSMs), are important for disaster risk reduction and famine early warning. These Systems require the best available weather inputs, as well as a long-term historical record to contextualize current observations. This article introduces the Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation System (FLDAS), a custom instance of the NASA Land Information System (LIS) framework. The FLDAS is routinely used to produce multi-model and multi-forcing estimates of hydro-climate states and fluxes over semi-arid, food insecure regions of Africa. These modeled data and derived products, like soil moisture percentiles and water availability, were designed and are currently used to complement FEWS NET’s operational remotely sensed rainfall, evapotranspiration, and vegetation observations. The 30+ years of monthly outputs from the FLDAS simulations are publicly available from the NASA Goddard Earth Science Data and Information Services Center (GES DISC) and recommended for use in hydroclimate studies, early warning applications, and by agro-meteorological scientists in Eastern, Southern, and Western Africa. Machine-accessible metadata file describing the reported data (ISA-Tab format)
E Elia - One of the best experts on this subject based on the ideXlab platform.
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the Land administration domain model ladm as the reference model for the cyprus Land Information System clis
Survey Review, 2013Co-Authors: E Elia, J A Zevenbergen, Christian LemmenAbstract:In this paper, the enhancement of the data model of the Cyprus Land Information System (CLIS), with the adoption of the Land administration domain model (LADM) is examined. The CLIS was established in 1999, within the Department of Lands and Surveys, to support the operation of the Cyprus cadastral System and has met the majority of its initial set goals. It is however now broadly accepted that the CLIS should be improved and upgraded, and a new data model should be introduced to facilitate the manipulation and provision of data to internal and external users/ customers in a more effective way. The need to enhance the CLIS coincides with the introduction of the LADM, which is under development within the Technical Committee 211 of the International Organization for Standardization and identified as ISO 19152. The LADM provides an abstract, conceptual schema with three basic packages: parties (such as people and organisations), administrative rights, responsibilities and restrictions (such as property rights) and spatial units (such as parcels, buildings and networks), with the latter having one subpackage: surveying and spatial representation [6]. [Note: In this moment (January 2012), the LADM is at the development stage of Final Draft International Standard]. In this paper, the basic entities of the CLIS are presented and restructured, in a way to comply with the LADM. After analysing the characteristics of LADM, it is concluded that this is compatible with CLIS, and can be used as a data model framework for CLIS’s upgrade. Thus, the Cyprus country profile is proposed. The adoption of the LADM is a great opportunity for the Department of Lands and Surveys to introduce an International Organization for Standardization standard model, based on model driven architecture, and to gain all the benefits derived from such a movement. Such benefits include the improvement in the effectiveness and the efficiency of the current System and the expansion of the services provided by CLIS to the broader Land administration System and to the Cyprus community. The new functionality includes: better structuring of the rights, responsibilities and restrictions (and related source documents); better fitting in the Information infrastructure, both national (e.g. valuation, taxation, building, address and person registrations) and international (e.g. INSPIRE cadastral parcels); and future capabilities for representing three-dimensional spatial units (e.g. legal spaces related to apartment or utility infrastructure).
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the Land administration domain model ladm as the reference model for the cyprus Land Information System clis
Bridging the Gap between Cultures FIG Working Week 2001 Marrakech Morocco 18-22 May 2011 TS02C-Spatial Data Infrastructures paper 4880, 2011Co-Authors: E Elia, Christian Lemmen, J A Zevenbergen, P J M Van OosteromAbstract:In this paper the enhancement of the data model of the Cyprus Land Information System (CLIS), with the adoption of the Land Administration Domain Model (LADM) is examined. The Cyprus Land Information System (CLIS), was established in 1999, within the Department of Lands and Surveys (DLS), to support the operation of the Cyprus cadastral System and has met the majority of its initial set goals. It is however now broadly accepted that the CLIS should be improved and upgraded, and a new data model should be introduced to facilitate the manipulation and provision of data to internal and external users/customers in a more effective way.
