Science.gov

Sample records for monsoon multidisciplinary analysis

  1. Multidisciplinary System Reliability Analysis

    NASA Technical Reports Server (NTRS)

    Mahadevan, Sankaran; Han, Song; Chamis, Christos C. (Technical Monitor)

    2001-01-01

    The objective of this study is to develop a new methodology for estimating the reliability of engineering systems that encompass multiple disciplines. The methodology is formulated in the context of the NESSUS probabilistic structural analysis code, developed under the leadership of NASA Glenn Research Center. The NESSUS code has been successfully applied to the reliability estimation of a variety of structural engineering systems. This study examines whether the features of NESSUS could be used to investigate the reliability of systems in other disciplines such as heat transfer, fluid mechanics, electrical circuits etc., without considerable programming effort specific to each discipline. In this study, the mechanical equivalence between system behavior models in different disciplines are investigated to achieve this objective. A new methodology is presented for the analysis of heat transfer, fluid flow, and electrical circuit problems using the structural analysis routines within NESSUS, by utilizing the equivalence between the computational quantities in different disciplines. This technique is integrated with the fast probability integration and system reliability techniques within the NESSUS code, to successfully compute the system reliability of multidisciplinary systems. Traditional as well as progressive failure analysis methods for system reliability estimation are demonstrated, through a numerical example of a heat exchanger system involving failure modes in structural, heat transfer and fluid flow disciplines.

  2. GRC RBCC Concept Multidisciplinary Analysis

    NASA Technical Reports Server (NTRS)

    Suresh, Ambady

    2001-01-01

    This report outlines the GRC RBCC Concept for Multidisciplinary Analysis. The multidisciplinary coupling procedure is presented, along with technique validations and axisymmetric multidisciplinary inlet and structural results. The NPSS (Numerical Propulsion System Simulation) test bed developments and code parallelization are also presented. These include milestones and accomplishments, a discussion of running R4 fan application on the PII cluster as compared to other platforms, and the National Combustor Code speedup.

  3. NPSS Multidisciplinary Integration and Analysis

    NASA Technical Reports Server (NTRS)

    Hall, Edward J.; Rasche, Joseph; Simons, Todd A.; Hoyniak, Daniel

    2006-01-01

    The objective of this task was to enhance the capability of the Numerical Propulsion System Simulation (NPSS) by expanding its reach into the high-fidelity multidisciplinary analysis area. This task investigated numerical techniques to convert between cold static to hot running geometry of compressor blades. Numerical calculations of blade deformations were iteratively done with high fidelity flow simulations together with high fidelity structural analysis of the compressor blade. The flow simulations were performed with the Advanced Ducted Propfan Analysis (ADPAC) code, while structural analyses were performed with the ANSYS code. High fidelity analyses were used to evaluate the effects on performance of: variations in tip clearance, uncertainty in manufacturing tolerance, variable inlet guide vane scheduling, and the effects of rotational speed on the hot running geometry of the compressor blades.

  4. Multidisciplinary Design and Analysis for Commercial Aircraft

    NASA Technical Reports Server (NTRS)

    Cummings, Russell M.; Freeman, H. JoAnne

    1999-01-01

    Multidisciplinary design and analysis (MDA) has become the normal mode of operation within most aerospace companies, but the impact of these changes have largely not been reflected at many universities. On an effort to determine if the emergence of multidisciplinary design concepts should influence engineering curricula, NASA has asked several universities (Virginia Tech, Georgia Tech, Clemson, BYU, and Cal Poly) to investigate the practicality of introducing MDA concepts within their undergraduate curricula. A multidisciplinary team of faculty, students, and industry partners evaluated the aeronautical engineering curriculum at Cal Poly. A variety of ways were found to introduce MDA themes into the curriculum without adding courses or units to the existing program. Both analytic and educational tools for multidisciplinary design of aircraft have been developed and implemented.

  5. Initial Multidisciplinary Design and Analysis Framework

    NASA Technical Reports Server (NTRS)

    Ozoroski, L. P.; Geiselhart, K. A.; Padula, S. L.; Li, W.; Olson, E. D.; Campbell, R. L.; Shields, E. W.; Berton, J. J.; Gray, J. S.; Jones, S. M.; Naiman, C. G.; Seidel, J. A.; Moore, K. T.; Naylor, B. A.; Townsend, S.

    2010-01-01

    Within the Supersonics (SUP) Project of the Fundamental Aeronautics Program (FAP), an initial multidisciplinary design & analysis framework has been developed. A set of low- and intermediate-fidelity discipline design and analysis codes were integrated within a multidisciplinary design and analysis framework and demonstrated on two challenging test cases. The first test case demonstrates an initial capability to design for low boom and performance. The second test case demonstrates rapid assessment of a well-characterized design. The current system has been shown to greatly increase the design and analysis speed and capability, and many future areas for development were identified. This work has established a state-of-the-art capability for immediate use by supersonic concept designers and systems analysts at NASA, while also providing a strong base to build upon for future releases as more multifidelity capabilities are developed and integrated.

  6. Convergence Estimates for Multidisciplinary Analysis and Optimization

    NASA Technical Reports Server (NTRS)

    Arian, Eyal

    1997-01-01

    A quantitative analysis of coupling between systems of equations is introduced. This analysis is then applied to problems in multidisciplinary analysis, sensitivity, and optimization. For the sensitivity and optimization problems both multidisciplinary and single discipline feasibility schemes are considered. In all these cases a "convergence factor" is estimated in terms of the Jacobians and Hessians of the system, thus it can also be approximated by existing disciplinary analysis and optimization codes. The convergence factor is identified with the measure for the "coupling" between the disciplines in the system. Applications to algorithm development are discussed. Demonstration of the convergence estimates and numerical results are given for a system composed of two non-linear algebraic equations, and for a system composed of two PDEs modeling aeroelasticity.

  7. Integrated multidisciplinary analysis tool IMAT users' guide

    NASA Technical Reports Server (NTRS)

    Meissner, Frances T. (Editor)

    1988-01-01

    The Integrated Multidisciplinary Analysis Tool (IMAT) is a computer software system developed at Langley Research Center. IMAT provides researchers and analysts with an efficient capability to analyze satellite controls systems influenced by structural dynamics. Using a menu-driven executive system, IMAT leads the user through the program options. IMAT links a relational database manager to commercial and in-house structural and controls analysis codes. This paper describes the IMAT software system and how to use it.

  8. Sensitivity Analysis of Multidisciplinary Rotorcraft Simulations

    NASA Technical Reports Server (NTRS)

    Wang, Li; Diskin, Boris; Biedron, Robert T.; Nielsen, Eric J.; Bauchau, Olivier A.

    2017-01-01

    A multidisciplinary sensitivity analysis of rotorcraft simulations involving tightly coupled high-fidelity computational fluid dynamics and comprehensive analysis solvers is presented and evaluated. An unstructured sensitivity-enabled Navier-Stokes solver, FUN3D, and a nonlinear flexible multibody dynamics solver, DYMORE, are coupled to predict the aerodynamic loads and structural responses of helicopter rotor blades. A discretely-consistent adjoint-based sensitivity analysis available in FUN3D provides sensitivities arising from unsteady turbulent flows and unstructured dynamic overset meshes, while a complex-variable approach is used to compute DYMORE structural sensitivities with respect to aerodynamic loads. The multidisciplinary sensitivity analysis is conducted through integrating the sensitivity components from each discipline of the coupled system. Numerical results verify accuracy of the FUN3D/DYMORE system by conducting simulations for a benchmark rotorcraft test model and comparing solutions with established analyses and experimental data. Complex-variable implementation of sensitivity analysis of DYMORE and the coupled FUN3D/DYMORE system is verified by comparing with real-valued analysis and sensitivities. Correctness of adjoint formulations for FUN3D/DYMORE interfaces is verified by comparing adjoint-based and complex-variable sensitivities. Finally, sensitivities of the lift and drag functions obtained by complex-variable FUN3D/DYMORE simulations are compared with sensitivities computed by the multidisciplinary sensitivity analysis, which couples adjoint-based flow and grid sensitivities of FUN3D and FUN3D/DYMORE interfaces with complex-variable sensitivities of DYMORE structural responses.

  9. Multi-Disciplinary Analysis and Optimization Frameworks

    NASA Technical Reports Server (NTRS)

    Naiman, Cynthia Gutierrez

    2009-01-01

    Since July 2008, the Multidisciplinary Analysis & Optimization Working Group (MDAO WG) of the Systems Analysis Design & Optimization (SAD&O) discipline in the Fundamental Aeronautics Program s Subsonic Fixed Wing (SFW) project completed one major milestone, Define Architecture & Interfaces for Next Generation Open Source MDAO Framework Milestone (9/30/08), and is completing the Generation 1 Framework validation milestone, which is due December 2008. Included in the presentation are: details of progress on developing the Open MDAO framework, modeling and testing the Generation 1 Framework, progress toward establishing partnerships with external parties, and discussion of additional potential collaborations

  10. NASA Multidisciplinary Design and Analysis Fellowship Program

    NASA Technical Reports Server (NTRS)

    Schrage, D. P.; Craig, J. I.; Mavris, D. N.; Hale, M. A.; DeLaurentis, D.

    1999-01-01

    This report summarizes the results of a multi-year training grant for the development and implementation of a Multidisciplinary Design and Analysis (MDA) Fellowship Program at Georgia Tech. The Program funded the creation of graduate MS and PhD degree programs in aerospace systems design, analysis and integration. It also provided prestigious Fellowships with associated Industry Internships for outstanding engineering students. The graduate program has become the foundation for a vigorous and productive research effort and has produced: 20 MS degrees, 7 Ph.D. degrees, and has contributed to 9 ongoing Ph.D. students. The results of the research are documented in 32 publications (23 of which are included on a companion CDROM) and 4 annual student design reports (included on a companion CDROM). The legacy of this critical funding is the Center for Aerospace Systems Analysis at Georgia Tech which is continuing the graduate program, the research, and the industry internships established by this grant.

  11. NASA Multidisciplinary Design and Analysis Fellowship Program

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This report is a Year 1 interim report of the progress on the NASA multidisciplinary Design and Analysis Fellowship Program covering the period, January 1, 1995 through September 30, 1995. It summarizes progress in establishing the MDA Fellowship Program at Georgia Tech during the initial year. Progress in the advertisement of the program, recruiting results for the 1995-96 academic year, placement of the Fellows in industry during Summer 1995, program development at the M.S. and Ph.D. levels, and collaboration and dissemination of results are summarized in this report. Further details of the first year's progress will be included in the report from the Year 1 Workshop to be held at NASA Langley on December 7-8, 1995.

  12. Multidisciplinary design optimization using response surface analysis

    NASA Technical Reports Server (NTRS)

    Unal, Resit

    1992-01-01

    Aerospace conceptual vehicle design is a complex process which involves multidisciplinary studies of configuration and technology options considering many parameters at many values. NASA Langley's Vehicle Analysis Branch (VAB) has detailed computerized analysis capabilities in most of the key disciplines required by advanced vehicle design. Given a configuration, the capability exists to quickly determine its performance and lifecycle cost. The next step in vehicle design is to determine the best settings of design parameters that optimize the performance characteristics. Typical approach to design optimization is experience based, trial and error variation of many parameters one at a time where possible combinations usually number in the thousands. However, this approach can either lead to a very long and expensive design process or to a premature termination of the design process due to budget and/or schedule pressures. Furthermore, one variable at a time approach can not account for the interactions that occur among parts of systems and among disciplines. As a result, vehicle design may be far from optimal. Advanced multidisciplinary design optimization (MDO) methods are needed to direct the search in an efficient and intelligent manner in order to drastically reduce the number of candidate designs to be evaluated. The payoffs in terms of enhanced performance and reduced cost are significant. A literature review yields two such advanced MDO methods used in aerospace design optimization; Taguchi methods and response surface methods. Taguchi methods provide a systematic and efficient method for design optimization for performance and cost. However, response surface method (RSM) leads to a better, more accurate exploration of the parameter space and to estimated optimum conditions with a small expenditure on experimental data. These two methods are described.

  13. Multi-Disciplinary System Reliability Analysis

    NASA Technical Reports Server (NTRS)

    Mahadevan, Sankaran; Han, Song

    1997-01-01

    The objective of this study is to develop a new methodology for estimating the reliability of engineering systems that encompass multiple disciplines. The methodology is formulated in the context of the NESSUS probabilistic structural analysis code developed under the leadership of NASA Lewis Research Center. The NESSUS code has been successfully applied to the reliability estimation of a variety of structural engineering systems. This study examines whether the features of NESSUS could be used to investigate the reliability of systems in other disciplines such as heat transfer, fluid mechanics, electrical circuits etc., without considerable programming effort specific to each discipline. In this study, the mechanical equivalence between system behavior models in different disciplines are investigated to achieve this objective. A new methodology is presented for the analysis of heat transfer, fluid flow, and electrical circuit problems using the structural analysis routines within NESSUS, by utilizing the equivalence between the computational quantities in different disciplines. This technique is integrated with the fast probability integration and system reliability techniques within the NESSUS code, to successfully compute the system reliability of multi-disciplinary systems. Traditional as well as progressive failure analysis methods for system reliability estimation are demonstrated, through a numerical example of a heat exchanger system involving failure modes in structural, heat transfer and fluid flow disciplines.

  14. Application of multidisciplinary analysis to gene expression.

    SciTech Connect

    Wang, Xuefel; Kang, Huining; Fields, Chris; Cowie, Jim R.; Davidson, George S.; Haaland, David Michael; Sibirtsev, Valeriy; Mosquera-Caro, Monica P.; Xu, Yuexian; Martin, Shawn Bryan; Helman, Paul; Andries, Erik; Ar, Kerem; Potter, Jeffrey; Willman, Cheryl L.; Murphy, Maurice H.

    2004-01-01

    Molecular analysis of cancer, at the genomic level, could lead to individualized patient diagnostics and treatments. The developments to follow will signal a significant paradigm shift in the clinical management of human cancer. Despite our initial hopes, however, it seems that simple analysis of microarray data cannot elucidate clinically significant gene functions and mechanisms. Extracting biological information from microarray data requires a complicated path involving multidisciplinary teams of biomedical researchers, computer scientists, mathematicians, statisticians, and computational linguists. The integration of the diverse outputs of each team is the limiting factor in the progress to discover candidate genes and pathways associated with the molecular biology of cancer. Specifically, one must deal with sets of significant genes identified by each method and extract whatever useful information may be found by comparing these different gene lists. Here we present our experience with such comparisons, and share methods developed in the analysis of an infant leukemia cohort studied on Affymetrix HG-U95A arrays. In particular, spatial gene clustering, hyper-dimensional projections, and computational linguistics were used to compare different gene lists. In spatial gene clustering, different gene lists are grouped together and visualized on a three-dimensional expression map, where genes with similar expressions are co-located. In another approach, projections from gene expression space onto a sphere clarify how groups of genes can jointly have more predictive power than groups of individually selected genes. Finally, online literature is automatically rearranged to present information about genes common to multiple groups, or to contrast the differences between the lists. The combination of these methods has improved our understanding of infant leukemia. While the complicated reality of the biology dashed our initial, optimistic hopes for simple answers from

  15. Multidisciplinary Analysis and Optimization Generation 1 and Next Steps

    NASA Technical Reports Server (NTRS)

    Naiman, Cynthia Gutierrez

    2008-01-01

    The Multidisciplinary Analysis & Optimization Working Group (MDAO WG) of the Systems Analysis Design & Optimization (SAD&O) discipline in the Fundamental Aeronautics Program s Subsonic Fixed Wing (SFW) project completed three major milestones during Fiscal Year (FY)08: "Requirements Definition" Milestone (1/31/08); "GEN 1 Integrated Multi-disciplinary Toolset" (Annual Performance Goal) (6/30/08); and "Define Architecture & Interfaces for Next Generation Open Source MDAO Framework" Milestone (9/30/08). Details of all three milestones are explained including documentation available, potential partner collaborations, and next steps in FY09.

  16. The West African monsoon: Contribution of the AMMA multidisciplinary programme to the study of a regional climate system.

    NASA Astrophysics Data System (ADS)

    Lebel, T.; Janicot, S.; Redelsperger, J. L.; Parker, D. J.; Thorncroft, C. D.

    2015-12-01

    The AMMA international project aims at improving our knowledge and understanding of the West African monsoon and its variability with an emphasis on daily-to-interannual timescales. AMMA is motivated by an interest in fundamental scientific issues and by the societal need for improved prediction of the WAM and its impacts on water resources, health and food security for West African nations. The West African monsoon (WAM) has a distinctive annual cycle in rainfall that remains a challenge to understand and predict. The location of peak rainfall, which resides in the Northern Hemisphere throughout the year, moves from the ocean to the land in boreal spring. Around the end of June there is a rapid shift in the location of peak rainfall between the coast and around 10°N where it remains until about the end of August. In September the peak rainfall returns equatorward at a relatively steady pace and is located over the ocean again by November. The fact that the peak rainfall migrates irregularly compared to the peak solar heating is due to the interactions that occur between the land, the atmosphere and the ocean. To gain a better understanding of this complex climate system, a large international research programme was launched in 2002, the biggest of its kind into environment and climate ever attempted in Africa. AMMA has involved a comprehensive field experiment bringing together ocean, land and atmospheric measurements, on timescales ranging from hourly and daily variability up to the changes in seasonal activity over a number of years. This presentation will focus on the description of the field programme and its accomplishments, and address some key questions that have been recently identified to form the core of AMMA-Phase 2.

  17. Analysis of Vegetation Index Variations and the Asian Monsoon Climate

    NASA Technical Reports Server (NTRS)

    Shen, Sunhung; Leptoukh, Gregory G.; Gerasimov, Irina

    2012-01-01

    Vegetation growth depends on local climate. Significant anthropogenic land cover and land use change activities over Asia have changed vegetation distribution as well. On the other hand, vegetation is one of the important land surface variables that influence the Asian Monsoon variability through controlling atmospheric energy and water vapor conditions. In this presentation, the mean and variations of vegetation index of last decade at regional scale resolution (5km and higher) from MODIS have been analyzed. Results indicate that the vegetation index has been reduced significantly during last decade over fast urbanization areas in east China, such as Yangtze River Delta, where local surface temperatures were increased significantly in term of urban heat Island. The relationship between vegetation Index and climate (surface temperature, precipitation) over a grassland in northern Asia and over a woody savannas in southeast Asia are studied. In supporting Monsoon Asian Integrated Regional Study (MAIRS) program, the data in this study have been integrated into Giovanni, the online visualization and analysis system at NASA GES DISC. Most images in this presentation are generated from Giovanni system.

  18. Recent Advances in Multidisciplinary Analysis and Optimization, part 1

    NASA Technical Reports Server (NTRS)

    Barthelemy, Jean-Francois M. (Editor)

    1989-01-01

    This three-part document contains a collection of technical papers presented at the Second NASA/Air Force Symposium on Recent Advances in Multidisciplinary Analysis and Optimization, held September 28-30, 1988 in Hampton, Virginia. The topics covered include: helicopter design, aeroelastic tailoring, control of aeroelastic structures, dynamics and control of flexible structures, structural design, design of large engineering systems, application of artificial intelligence, shape optimization, software development and implementation, and sensitivity analysis.

  19. Recent Advances in Multidisciplinary Analysis and Optimization, part 2

    NASA Technical Reports Server (NTRS)

    Barthelemy, Jean-Francois M. (Editor)

    1989-01-01

    This three-part document contains a collection of technical papers presented at the Second NASA/Air Force Symposium on Recent Advances in Multidisciplinary Analysis and Optimization, held September 28-30, 1988 in Hampton, Virginia. The topics covered include: helicopter design, aeroelastic tailoring, control of aeroelastic structures, dynamics and control of flexible structures, structural design, design of large engineering systems, application of artificial intelligence, shape optimization, software development and implementation, and sensitivity analysis.

  20. Recent Advances in Multidisciplinary Analysis and Optimization, part 3

    NASA Technical Reports Server (NTRS)

    Barthelemy, Jean-Francois M. (Editor)

    1989-01-01

    This three-part document contains a collection of technical papers presented at the Second NASA/Air Force Symposium on Recent Advances in Multidisciplinary Analysis and Optimization, held September 28-30, 1988 in Hampton, Virginia. The topics covered include: aircraft design, aeroelastic tailoring, control of aeroelastic structures, dynamics and control of flexible structures, structural design, design of large engineering systems, application of artificial intelligence, shape optimization, software development and implementation, and sensitivity analysis.

  1. Recent Experiences in Multidisciplinary Analysis and Optimization, part 2

    NASA Technical Reports Server (NTRS)

    Sobieski, J. (Compiler)

    1984-01-01

    The papers presented at the NASA Symposium on Recent Experiences in Multidisciplinary Analysis and Optimization held at NASA Langley Research Center, Hampton, Virginia, April 24 to 26, 1984 are given. The purposes of the symposium were to exchange information about the status of the application of optimization and the associated analyses in industry or research laboratories to real life problems and to examine the directions of future developments.

  2. NASA Aeronautics Multidisciplinary Analysis and Design Fellowship Program

    NASA Technical Reports Server (NTRS)

    Grossman, B.; Guerdal, Z.; Haftka, R. T.; Kapania, R. K.; Mason, W. H.; Mook, D. T.

    1998-01-01

    For a number of years, Virginia Tech had been on the forefront of research in the area of multidisciplinary analysis and design. In June of 1994, faculty members from aerospace and ocean engineering, engineering science and mechanics, mechanical engineering, industrial engineering, mathematics and computer sciences, at Virginia Tech joined together to form the Multidisciplinary Analysis and Design (MAD) Center for Advanced Vehicles. The center was established with the single goal: to perform research that is relevant to the needs of the US industry and to foster collaboration between the university, government and industry. In October of 1994, the center was chosen by NASA headquarters as one of the five university centers to establish a fellowship program to develop a graduate program in multidisciplinary analysis and design. The fellowship program provides full stipend and tuition support for seven U. S. students per year during their graduate studies. To advise us regarding the problems faced by the industry, an industrial advisory board has been formed consisting of representatives from industry as well as government laboratories. The function of the advisory board is to channel information from its member companies to faculty members concerning problems that need research attention in the general area of multidisciplinary design optimization (MDO). The faculty and their graduate students make proposals to the board on how to address these problems. At the annual board meeting in Blacksburg, the board discusses the proposals and suggests which students get funded under the NASA fellowship program. All students participating in the program are required to spend 3-6 months in industry working on their research projects. We are completing the third year of the fellowship program and have had three advisory board meetings in Blacksburg.

  3. Multidisciplinary Analysis and Optimal Design: As Easy as it Sounds?

    NASA Technical Reports Server (NTRS)

    Moore, Greg; Chainyk, Mike; Schiermeier, John

    2004-01-01

    The viewgraph presentation examines optimal design for precision, large aperture structures. Discussion focuses on aspects of design optimization, code architecture and current capabilities, and planned activities and collaborative area suggestions. The discussion of design optimization examines design sensitivity analysis; practical considerations; and new analytical environments including finite element-based capability for high-fidelity multidisciplinary analysis, design sensitivity, and optimization. The discussion of code architecture and current capabilities includes basic thermal and structural elements, nonlinear heat transfer solutions and process, and optical modes generation.

  4. Multidisciplinary analysis of actively controlled large flexible spacecraft

    NASA Technical Reports Server (NTRS)

    Cooper, Paul A.; Young, John W.; Sutter, Thomas R.

    1986-01-01

    The control of Flexible Structures (COFS) program has supported the development of an analysis capability at the Langley Research Center called the Integrated Multidisciplinary Analysis Tool (IMAT) which provides an efficient data storage and transfer capability among commercial computer codes to aid in the dynamic analysis of actively controlled structures. IMAT is a system of computer programs which transfers Computer-Aided-Design (CAD) configurations, structural finite element models, material property and stress information, structural and rigid-body dynamic model information, and linear system matrices for control law formulation among various commercial applications programs through a common database. Although general in its formulation, IMAT was developed specifically to aid in the evaluation of the structures. A description of the IMAT system and results of an application of the system are given.

  5. A Multidisciplinary Approach to Mixer-Ejector Analysis and Design

    NASA Technical Reports Server (NTRS)

    Hendricks, Eric, S.; Seidel, Jonathan, A.

    2012-01-01

    The design of an engine for a civil supersonic aircraft presents a difficult multidisciplinary problem to propulsion system engineers. There are numerous competing requirements for the engine, such as to be efficient during cruise while yet quiet enough at takeoff to meet airport noise regulations. The use of mixer-ejector nozzles presents one possible solution to this challenge. However, designing a mixer-ejector which will successfully address both of these concerns is a difficult proposition. Presented in this paper is an integrated multidisciplinary approach to the analysis and design of these systems. A process that uses several low-fidelity tools to evaluate both the performance and acoustics of mixer-ejectors nozzles is described. This process is further expanded to include system-level modeling of engines and aircraft to determine the effects on mission performance and noise near airports. The overall process is developed in the OpenMDAO framework currently being developed by NASA. From the developed process, sample results are given for a notional mixer-ejector design, thereby demonstrating the capabilities of the method.

  6. The Third Air Force/NASA Symposium on Recent Advances in Multidisciplinary Analysis and Optimization

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The third Air Force/NASA Symposium on Recent Advances in Multidisciplinary Analysis and Optimization was held on 24-26 Sept. 1990. Sessions were on the following topics: dynamics and controls; multilevel optimization; sensitivity analysis; aerodynamic design software systems; optimization theory; analysis and design; shape optimization; vehicle components; structural optimization; aeroelasticity; artificial intelligence; multidisciplinary optimization; and composites.

  7. Recent Experiences in Multidisciplinary Analysis and Optimization, part 1

    NASA Technical Reports Server (NTRS)

    Sobieski, J. (Compiler)

    1984-01-01

    Papers presented at the NASA Symposium on Recent Experiences in Multidisciplinary Analysis and Optimization held at NASA Langley Research Center, Hampton, Virginia April 24 to 26, 1984 are given. The purposes of the symposium were to exchange information about the status of the application of optimization and associated analyses in industry or research laboratories to real life problems and to examine the directions of future developments. Information exchange has encompassed the following: (1) examples of successful applications; (2) attempt and failure examples; (3) identification of potential applications and benefits; (4) synergistic effects of optimized interaction and trade-offs occurring among two or more engineering disciplines and/or subsystems in a system; and (5) traditional organization of a design process as a vehicle for or an impediment to the progress in the design methodology.

  8. PAYCOS: A new multidisciplinary analysis program for hypersonic vehicle design

    NASA Technical Reports Server (NTRS)

    Stubbe, J. R.

    1990-01-01

    The Payload Conceptual Sizing Code (PAYCOS), a new multidisciplinary computer program for use in the conceptual development phase of hypersonic lifting vehicles (HV's), is described. The program allows engineers to rapidly determine the feasibility of an HV concept and then improve upon the concept by means of optimization theory. The code contains analysis modules for aerodynamics, thermodynamics, mass properties, flight stability, controls, loads, structures, and packaging. Motivation for the code lies with the increased complexity of HV's over their body-of-revolution ballistic predecessors. With these new shapes, the need to rapidly screen out poor concepts and actively develop new and better concepts is an even more crucial part of the early design process. Preliminary results are given which demonstrate the optimization capabilities of the code.

  9. The Role of Multiphysics Simulation in Multidisciplinary Analysis

    NASA Technical Reports Server (NTRS)

    Rifai, Steven M.; Ferencz, Robert M.; Wang, Wen-Ping; Spyropoulos, Evangelos T.; Lawrence, Charles; Melis, Matthew E.

    1998-01-01

    This article describes the applications of the Spectrum(Tm) Solver in Multidisciplinary Analysis (MDA). Spectrum, a multiphysics simulation software based on the finite element method, addresses compressible and incompressible fluid flow, structural, and thermal modeling as well as the interaction between these disciplines. Multiphysics simulation is based on a single computational framework for the modeling of multiple interacting physical phenomena. Interaction constraints are enforced in a fully-coupled manner using the augmented-Lagrangian method. Within the multiphysics framework, the finite element treatment of fluids is based on Galerkin-Least-Squares (GLS) method with discontinuity capturing operators. The arbitrary-Lagrangian-Eulerian method is utilized to account for deformable fluid domains. The finite element treatment of solids and structures is based on the Hu-Washizu variational principle. The multiphysics architecture lends itself naturally to high-performance parallel computing. Aeroelastic, propulsion, thermal management and manufacturing applications are presented.

  10. Multidisciplinary aeroelastic analysis of a generic hypersonic vehicle

    NASA Technical Reports Server (NTRS)

    Gupta, K. K.; Petersen, K. L.

    1993-01-01

    This paper presents details of a flutter and stability analysis of aerospace structures such as hypersonic vehicles. Both structural and aerodynamic domains are discretized by the common finite element technique. A vibration analysis is first performed by the STARS code employing a block Lanczos solution scheme. This is followed by the generation of a linear aerodynamic grid for subsequent linear flutter analysis within subsonic and supersonic regimes of the flight envelope; the doublet lattice and constant pressure techniques are employed to generate the unsteady aerodynamic forces. Flutter analysis is then performed for several representative flight points. The nonlinear flutter solution is effected by first implementing a CFD solution of the entire vehicle. Thus, a 3-D unstructured grid for the entire flow domain is generated by a moving front technique. A finite element Euler solution is then implemented employing a quasi-implicit as well as an explicit solution scheme. A novel multidisciplinary analysis is next effected that employs modal and aerodynamic data to yield aerodynamic damping characteristics. Such analyses are performed for a number of flight points to yield a large set of pertinent data that define flight flutter characteristics of the vehicle. This paper outlines the finite-element-based integrated analysis procedures in detail, which is followed by the results of numerical analyses of flight flutter simulation.

  11. Multidisciplinary aeroelastic analysis of a generic hypersonic vehicle

    NASA Astrophysics Data System (ADS)

    Gupta, K. K.; Petersen, K. L.

    1993-10-01

    This paper presents details of a flutter and stability analysis of aerospace structures such as hypersonic vehicles. Both structural and aerodynamic domains are discretized by the common finite element technique. A vibration analysis is first performed by the STARS code employing a block Lanczos solution scheme. This is followed by the generation of a linear aerodynamic grid for subsequent linear flutter analysis within subsonic and supersonic regimes of the flight envelope; the doublet lattice and constant pressure techniques are employed to generate the unsteady aerodynamic forces. Flutter analysis is then performed for several representative flight points. The nonlinear flutter solution is effected by first implementing a CFD solution of the entire vehicle. Thus, a 3-D unstructured grid for the entire flow domain is generated by a moving front technique. A finite element Euler solution is then implemented employing a quasi-implicit as well as an explicit solution scheme. A novel multidisciplinary analysis is next effected that employs modal and aerodynamic data to yield aerodynamic damping characteristics. Such analyses are performed for a number of flight points to yield a large set of pertinent data that define flight flutter characteristics of the vehicle. This paper outlines the finite-element-based integrated analysis procedures in detail, which is followed by the results of numerical analyses of flight flutter simulation.

  12. NASA Aeronautics Multidisciplinary Analysis and Design Fellowship Program

    NASA Technical Reports Server (NTRS)

    Grossman, B.; Gurdal, Z.; Kapania, R. K.; Mason, W. H.; Schetz, J. A.

    1999-01-01

    This program began as a grant from NASA Headquarters, NGT-10025, which was in effect from 10/l/93 until 10/31/96. The remaining funding for this effort was transferred from NASA Headquarters to NASA Langley and a new grant NGT-1-52155 was issued covering the period II/l/96 to 5/15/99. This report serves as the final report of NGT-1-52155. For a number of years, Virginia Tech had been on the forefront of research in the area of multidisciplinary analysis and design. In June of 1994, faculty members from aerospace and ocean engineering, engineering science and mechanics, mechanical engineering, industrial engineering, mathematics and computer sciences, at Virginia Tech joined together to form the Multidisciplinary Analysis and Design (MAD) Center for Advanced Vehicles. The center was established with the single goal: to perform research that is relevant to the needs of the US industry and to foster collaboration between the university, government and industry. In October of 1994, the center was chosen by NASA headquarters as one of the five university centers to establish a fellowship program to develop a graduate program in multidisciplinary analysis and design. The fellowship program provides full stipend and tuition support for seven U. S. students per year during their graduate studies. The grant is currently being administered by the NMO Branch of NASA Langley. To advise us regarding the problems faced by the industry, an industrial advisory board has been formed consisting of representatives from industry as well as government laboratories. The present membership includes major aerospace companies: Aurora Flight Sciences, Boeing: Philadelphia, Boeing: Long Beach, Boeing: Seattle, Boeing: St. Louis, Cessna, Ford, General Electric, Hughes, Lockheed-Martin: Palo Alto, Northrop-Grumman, Sikorsky, smaller, aerospace software companies: Aerosoft, Phoenix Integration and Proteus Engineering, along with representatives from government agencies, including: NASA Ames

  13. Entropy analysis of stable isotopes in precipitation: tracing the monsoon systems in China

    PubMed Central

    Wang, Tao; Chen, Jiansheng; Li, Ling

    2016-01-01

    Due to the complexity of monsoon systems and random behaviors of isotope tracers, conventional methods are not adequate for uncovering detailed information about monsoon activities from typically limited precipitation isotope data. We developed a new approach based on the entropy theory to analyze such data with a focus on the monsoon systems in China, dealing with the complexity of these systems and data deficiency. Using precipitation isotope data from 42 selected stations in and around China within the GNIP network, we computed entropies associated with D and 18O. These entropies were found to relate linearly to each other with a proportionality factor close to unity. The spatial variations of the D and 18O entropy in the study area revealed the origins, extents and pathways of the Chinese monsoon systems, as well as their interactions. While further investigation is needed at a greater (global) scale, this study has demonstrated how the entropy theory enables an in-depth analysis of precipitation isotope data to trace the pathway and determine the range of a monsoon system. PMID:27507656

  14. Entropy analysis of stable isotopes in precipitation: tracing the monsoon systems in China.

    PubMed

    Wang, Tao; Chen, Jiansheng; Li, Ling

    2016-08-10

    Due to the complexity of monsoon systems and random behaviors of isotope tracers, conventional methods are not adequate for uncovering detailed information about monsoon activities from typically limited precipitation isotope data. We developed a new approach based on the entropy theory to analyze such data with a focus on the monsoon systems in China, dealing with the complexity of these systems and data deficiency. Using precipitation isotope data from 42 selected stations in and around China within the GNIP network, we computed entropies associated with D and (18)O. These entropies were found to relate linearly to each other with a proportionality factor close to unity. The spatial variations of the D and (18)O entropy in the study area revealed the origins, extents and pathways of the Chinese monsoon systems, as well as their interactions. While further investigation is needed at a greater (global) scale, this study has demonstrated how the entropy theory enables an in-depth analysis of precipitation isotope data to trace the pathway and determine the range of a monsoon system.

  15. An integrated risk analysis methodology in a multidisciplinary design environment

    NASA Astrophysics Data System (ADS)

    Hampton, Katrina Renee

    Design of complex, one-of-a-kind systems, such as space transportation systems, is characterized by high uncertainty and, consequently, high risk. It is necessary to account for these uncertainties in the design process to produce systems that are more reliable. Systems designed by including uncertainties and managing them, as well, are more robust and less prone to poor operations as a result of parameter variability. The quantification, analysis and mitigation of uncertainties are challenging tasks as many systems lack historical data. In such an environment, risk or uncertainty quantification becomes subjective because input data is based on professional judgment. Additionally, there are uncertainties associated with the analysis tools and models. Both the input data and the model uncertainties must be considered for a multi disciplinary systems level risk analysis. This research synthesizes an integrated approach for developing a method for risk analysis. Expert judgment methodology is employed to quantify external risk. This methodology is then combined with a Latin Hypercube Sampling - Monte Carlo simulation to propagate uncertainties across a multidisciplinary environment for the overall system. Finally, a robust design strategy is employed to mitigate risk during the optimization process. This type of approach to risk analysis is conducive to the examination of quantitative risk factors. The core of this research methodology is the theoretical framework for uncertainty propagation. The research is divided into three stages or modules. The first two modules include the identification/quantification and propagation of uncertainties. The third module involves the management of uncertainties or response optimization. This final module also incorporates the integration of risk into program decision-making. The risk analysis methodology, is applied to a launch vehicle conceptual design study at NASA Langley Research Center. The launch vehicle multidisciplinary

  16. Multidisciplinary Expert-aided Analysis and Design (MEAD)

    NASA Technical Reports Server (NTRS)

    Hummel, Thomas C.; Taylor, James

    1989-01-01

    The MEAD Computer Program (MCP) is being developed under the Multidisciplinary Expert-Aided Analysis and Design (MEAD) Project as a CAD environment in which integrated flight, propulsion, and structural control systems can be designed and analyzed. The MCP has several embedded computer-aided control engineering (CACE) packages, a user interface (UI), a supervisor, a data-base manager (DBM), and an expert system (ES). The supervisor monitors and coordinates the operation of the CACE packages, the DBM; the ES, and the UI. The DBM tracks the control design process. Models created or installed by the MCP are tracked by date and version, and results are associated with the specific model version with which they were generated. The ES is used to relieve the control engineer from tedious and cumbersome tasks in the iterative design process. The UI provides the capability for a novice as well as an expert to utilize the MCP easily and effectively. The MCP version 2(MCP-2.0) is fully developed for flight control system design and analysis. Propulsion system modeling, analysis, and simulation is also supported; the same is true for structural models represented in state-space form. The ultimate goal is to cover the integration of flight, propulsion, and structural control engineering, including all discipline-specific functionality and interfaces. The current MCP-2.0 components and functionality are discussed.

  17. NCC: A Multidisciplinary Design/Analysis Tool for Combustion Systems

    NASA Technical Reports Server (NTRS)

    Liu, Nan-Suey; Quealy, Angela

    1999-01-01

    A multi-disciplinary design/analysis tool for combustion systems is critical for optimizing the low-emission, high-performance combustor design process. Based on discussions between NASA Lewis Research Center and the jet engine companies, an industry-government team was formed in early 1995 to develop the National Combustion Code (NCC), which is an integrated system of computer codes for the design and analysis of combustion systems. NCC has advanced features that address the need to meet designer's requirements such as "assured accuracy", "fast turnaround", and "acceptable cost". The NCC development team is comprised of Allison Engine Company (Allison), CFD Research Corporation (CFDRC), GE Aircraft Engines (GEAE), NASA Lewis Research Center (LeRC), and Pratt & Whitney (P&W). This development team operates under the guidance of the NCC steering committee. The "unstructured mesh" capability and "parallel computing" are fundamental features of NCC from its inception. The NCC system is composed of a set of "elements" which includes grid generator, main flow solver, turbulence module, turbulence and chemistry interaction module, chemistry module, spray module, radiation heat transfer module, data visualization module, and a post-processor for evaluating engine performance parameters. Each element may have contributions from several team members. Such a multi-source multi-element system needs to be integrated in a way that facilitates inter-module data communication, flexibility in module selection, and ease of integration.

  18. Framework for Multidisciplinary Analysis, Design, and Optimization with High-Fidelity Analysis Tools

    NASA Technical Reports Server (NTRS)

    Orr, Stanley A.; Narducci, Robert P.

    2009-01-01

    A plan is presented for the development of a high fidelity multidisciplinary optimization process for rotorcraft. The plan formulates individual disciplinary design problems, identifies practical high-fidelity tools and processes that can be incorporated in an automated optimization environment, and establishes statements of the multidisciplinary design problem including objectives, constraints, design variables, and cross-disciplinary dependencies. Five key disciplinary areas are selected in the development plan. These are rotor aerodynamics, rotor structures and dynamics, fuselage aerodynamics, fuselage structures, and propulsion / drive system. Flying qualities and noise are included as ancillary areas. Consistency across engineering disciplines is maintained with a central geometry engine that supports all multidisciplinary analysis. The multidisciplinary optimization process targets the preliminary design cycle where gross elements of the helicopter have been defined. These might include number of rotors and rotor configuration (tandem, coaxial, etc.). It is at this stage that sufficient configuration information is defined to perform high-fidelity analysis. At the same time there is enough design freedom to influence a design. The rotorcraft multidisciplinary optimization tool is built and substantiated throughout its development cycle in a staged approach by incorporating disciplines sequentially.

  19. Multidisciplinary Design, Analysis, and Optimization Tool Development Using a Genetic Algorithm

    NASA Technical Reports Server (NTRS)

    Pak, Chan-gi; Li, Wesley

    2009-01-01

    Multidisciplinary design, analysis, and optimization using a genetic algorithm is being developed at the National Aeronautics and Space Administration Dryden Flight Research Center (Edwards, California) to automate analysis and design process by leveraging existing tools to enable true multidisciplinary optimization in the preliminary design stage of subsonic, transonic, supersonic, and hypersonic aircraft. This is a promising technology, but faces many challenges in large-scale, real-world application. This report describes current approaches, recent results, and challenges for multidisciplinary design, analysis, and optimization as demonstrated by experience with the Ikhana fire pod design.!

  20. The Future of Public Relations: A Multi-Disciplinary Analysis.

    ERIC Educational Resources Information Center

    Neff, Bonita Dostal

    Literature reviews have indicated there is a lack of data on public relations curriculum development for communication and business departments. Observations have been reported of "spectacular" growth in public relations courses in communication (Grunig, 1989). The first multi-disciplinary survey (3,201 college and university catalogs)…

  1. Multi-Satellite Synergy for Aerosol Analysis in the Asian Monsoon Region

    NASA Technical Reports Server (NTRS)

    Ichoku, Charles; Petrenko, Maksym

    2012-01-01

    Atmospheric aerosols represent one of the greatest uncertainties in environmental and climate research, particularly in tropical monsoon regions such as the Southeast Asian regions, where significant contributions from a variety of aerosol sources and types is complicated by unstable atmospheric dynamics. Although aerosols are now routinely retrieved from multiple satellite Sensors, in trying to answer important science questions about aerosol distribution, properties, and impacts, researchers often rely on retrievals from only one or two sensors, thereby running the risk of incurring biases due to sensor/algorithm peculiarities. We are conducting detailed studies of aerosol retrieval uncertainties from various satellite sensors (including Terra-/ Aqua-MODIS, Terra-MISR, Aura-OMI, Parasol-POLDER, SeaWiFS, and Calipso-CALIOP), based on the collocation of these data products over AERONET and other important ground stations, within the online Multi-sensor Aerosol Products Sampling System (MAPSS) framework that was developed recently. Such analyses are aimed at developing a synthesis of results that can be utilized in building reliable unified aerosol information and climate data records from multiple satellite measurements. In this presentation, we will show preliminary results of. an integrated comparative uncertainly analysis of aerosol products from multiple satellite sensors, particularly focused on the Asian Monsoon region, along with some comparisons from the African Monsoon region.

  2. Analysis of intraseasonal convective variability modes over West Africa during the monsoon season

    NASA Astrophysics Data System (ADS)

    Ceratto, Jeffrey

    Intraseasonal variability of rainfall within the West African Monsoon has been shown to be an important factor in the weather of this region. Multiple factors have been found to contribute to variability at this timescale. Mounier, et al (2008) use EOF analysis to uncover and describe a quasi-stationary dipole of precipitation between the West African Monsoon system and the West Atlantic/Caribbean Sea. This mode, termed the Quasi Biweekly Zonal Dipole mode, operates on timescales of roughly 13 days. The stationary nature of this dipole is focused upon in their work, while the role of Kelvin waves in the mode are considered secondary. In this work, the role of Kelvin waves in the dipole mode is considered. Regression analyses are performed with time lags to observe how the dipole evolves with time. Kelvin waves are observed to dominate the timing and the phase of the dipole mode. Dynamical regressions indicate a possible source region for these Kelvin waves, over the South American continent, as well as the effects the Kelvin waves have on the West African Monsoon system as they enter and exit the region. Impacts on the strength of the Saharan Heat Low and on African Easterly Wave activity are observed. A case study highlighting Kelvin wave activity in relation to the QBZD is also considered. The second EOF pattern is also examined with lagged regressions; a relationship is found between it and the first EOF pattern.

  3. Multidisciplinary High-Fidelity Analysis and Optimization of Aerospace Vehicles. Part 2; Preliminary Results

    NASA Technical Reports Server (NTRS)

    Walsh, J. L.; Weston, R. P.; Samareh, J. A.; Mason, B. H.; Green, L. L.; Biedron, R. T.

    2000-01-01

    An objective of the High Performance Computing and Communication Program at the NASA Langley Research Center is to demonstrate multidisciplinary shape and sizing optimization of a complete aerospace vehicle configuration by using high-fidelity finite-element structural analysis and computational fluid dynamics aerodynamic analysis in a distributed, heterogeneous computing environment that includes high performance parallel computing. A software system has been designed and implemented to integrate a set of existing discipline analysis codes, some of them computationally intensive, into a distributed computational environment for the design of a high-speed civil transport configuration. The paper describes both the preliminary results from implementing and validating the multidisciplinary analysis and the results from an aerodynamic optimization. The discipline codes are integrated by using the Java programming language and a Common Object Request Broker Architecture compliant software product. A companion paper describes the formulation of the multidisciplinary analysis and optimization system.

  4. Application of advanced multidisciplinary analysis and optimization methods to vehicle design synthesis

    NASA Technical Reports Server (NTRS)

    Consoli, Robert David; Sobieszczanski-Sobieski, Jaroslaw

    1990-01-01

    Advanced multidisciplinary analysis and optimization methods, namely system sensitivity analysis and non-hierarchical system decomposition, are applied to reduce the cost and improve the visibility of an automated vehicle design synthesis process. This process is inherently complex due to the large number of functional disciplines and associated interdisciplinary couplings. Recent developments in system sensitivity analysis as applied to complex non-hierarchic multidisciplinary design optimization problems enable the decomposition of these complex interactions into sub-processes that can be evaluated in parallel. The application of these techniques results in significant cost, accuracy, and visibility benefits for the entire design synthesis process.

  5. Multidisciplinary Design, Analysis, and Optimization Tool Development using a Genetic Algorithm

    NASA Technical Reports Server (NTRS)

    Pak, Chan-gi; Li, Wesley

    2008-01-01

    Multidisciplinary design, analysis, and optimization using a genetic algorithm is being developed at the National Aeronautics and Space A dministration Dryden Flight Research Center to automate analysis and design process by leveraging existing tools such as NASTRAN, ZAERO a nd CFD codes to enable true multidisciplinary optimization in the pr eliminary design stage of subsonic, transonic, supersonic, and hypers onic aircraft. This is a promising technology, but faces many challe nges in large-scale, real-world application. This paper describes cur rent approaches, recent results, and challenges for MDAO as demonstr ated by our experience with the Ikhana fire pod design.

  6. A qualitative analysis of communication between members of a hospital-based multidisciplinary lung cancer team.

    PubMed

    Rowlands, S; Callen, J

    2013-01-01

    The aim of the study was to explore how patient information is communicated between health professionals within a multidisciplinary hospital-based lung cancer team and to identify mechanisms to improve these communications. A qualitative method was employed using semi-structured in-depth interviews with a representative sample (n = 22) of members of a multidisciplinary hospital-based lung cancer team including medical, nursing and allied health professionals. Analysis was undertaken using a thematic grounded theory approach to derive key themes to describe communication patterns within the team and how communication could be improved. Two themes with sub-themes were identified: (1) characteristics of communication between team members including the impact of role on direction of communications, and doctors' dominance in communications; and (2) channels of communication including, preference for face-to-face and the suboptimal roles of the Multidisciplinary Team Meeting and the hospital medical record as mediums for communication. Traditional influences of role delineation and the dominance of doctors were found to impact on communication within the multidisciplinary hospital-based lung cancer team. Existing guidelines on implementation of multidisciplinary cancer care fail to address barriers to effective team communication. The paper-based medical record does not support team communications and alternative electronic solutions need to be used.

  7. Projected change in East Asian summer monsoon by dynamic downscaling: Moisture budget analysis

    NASA Astrophysics Data System (ADS)

    Jung, Chun-Yong; Shin, Ho-Jeong; Jang, Chan Joo; Kim, Hyung-Jin

    2015-02-01

    The summer monsoon considerably affects water resource and natural hazards including flood and drought in East Asia, one of the world's most densely populated area. In this study, we investigate future changes in summer precipitation over East Asia induced by global warming through dynamical downscaling with the Weather Research and Forecast model. We have selected a global model from the Coupled Model Intercomparison Project Phase 5 based on an objective evaluation for East Asian summer monsoon and applied its climate change under Representative Concentration Pathway 4.5 scenario to a pseudo global warming method. Unlike the previous studies that focused on a qualitative description of projected precipitation changes over East Asia, this study tried to identify the physical causes of the precipitation changes by analyzing a local moisture budget. Projected changes in precipitation over the eastern foothills area of Tibetan Plateau including Sichuan Basin and Yangtze River displayed a contrasting pattern: a decrease in its northern area and an increase in its southern area. A local moisture budget analysis indicated the precipitation increase over the southern area can be mainly attributed to an increase in horizontal wind convergence and surface evaporation. On the other hand, the precipitation decrease over the northern area can be largely explained by horizontal advection of dry air from the northern continent and by divergent wind flow. Regional changes in future precipitation in East Asia are likely to be attributed to different mechanisms which can be better resolved by regional dynamical downscaling.

  8. Orbital forcing on West African monsoon system revealed by KZai 02 pollen record spectral analysis

    NASA Astrophysics Data System (ADS)

    Dalibard, Mathieu; Popescu, Speranta-Maria; Pittet, Bernard; Fernandez, Vincent; Marsset, Tania; Droz, Laurence; Suc, Jean-Pierre

    2013-04-01

    The present-day intertropical climate is forced by yearly fluctuations of insolation reorganizing pressure cells. They control, via the wind system, the variations of the precipitation front known as the InterTropical Convergence Zone (ITCZ). Its latitudinal oscillation drives a strong seasonality of rainfalls over Africa. However, connections between African climate during Pleistocene and orbital forcing are blurred by high-latitudes and local direct influence of insolation and need further investigations. The study of KZai 02 core pollen content provides a high-resolution record of changes in West African plant ecosystems during the last 160 kyrs. Spectral analyses were performed on pollen signals to identify periodicity in vegetation dynamics related to environmental fluctuations. The large range of frequencies detected testifies for the sensibility of African biotopes to past climate fluctuations. Milankovitch parameters, especially precession, are identified within variations of the ecological groups of KZai 02 pollen record and interpreted in terms of West African monsoon system variability. Asynchrony in the different plant ecosystem fluctuations suggests the out of step influence of several climatic parameters (precipitation, CO2, temperature) involving local insolation and high-latitude influence. Spectral analysis also reveals sub-Milankovitch periods related to (1) Heinrich and Dansgaard/Oeschger glacial pulsation events and (2) East Asian monsoon oscillations controlled by ice sheet pulses testifying for the strong relationship between low- and high-latitude climate changes.

  9. Development of Response Surface Models for Rapid Analysis and Multidisciplinary Optimization of Launch Vehicle Design Concepts

    NASA Technical Reports Server (NTRS)

    Unal, Resit

    1999-01-01

    Multidisciplinary design optimization (MDO) is an important step in the design and evaluation of launch vehicles, since it has a significant impact on performance and lifecycle cost. The objective in MDO is to search the design space to determine the values of design parameters that optimize the performance characteristics subject to system constraints. Vehicle Analysis Branch (VAB) at NASA Langley Research Center has computerized analysis tools in many of the disciplines required for the design and analysis of launch vehicles. Vehicle performance characteristics can be determined by the use of these computerized analysis tools. The next step is to optimize the system performance characteristics subject to multidisciplinary constraints. However, most of the complex sizing and performance evaluation codes used for launch vehicle design are stand-alone tools, operated by disciplinary experts. They are, in general, difficult to integrate and use directly for MDO.

  10. Online Time Series Analysis of Land Products over Asia Monsoon Region via Giovanni

    NASA Technical Reports Server (NTRS)

    Shen, Suhung; Leptoukh, Gregory G.; Gerasimov, Irina

    2011-01-01

    Time series analysis is critical to the study of land cover/land use changes and climate. Time series studies at local-to-regional scales require higher spatial resolution, such as 1km or less, data. MODIS land products of 250m to 1km resolution enable such studies. However, such MODIS land data files are distributed in 10ox10o tiles, due to large data volumes. Conducting a time series study requires downloading all tiles that include the study area for the time period of interest, and mosaicking the tiles spatially. This can be an extremely time-consuming process. In support of the Monsoon Asia Integrated Regional Study (MAIRS) program, NASA GES DISC (Goddard Earth Sciences Data and Information Services Center) has processed MODIS land products at 1 km resolution over the Asia monsoon region (0o-60oN, 60o-150oE) with a common data structure and format. The processed data have been integrated into the Giovanni system (Goddard Interactive Online Visualization ANd aNalysis Infrastructure) that enables users to explore, analyze, and download data over an area and time period of interest easily. Currently, the following regional MODIS land products are available in Giovanni: 8-day 1km land surface temperature and active fire, monthly 1km vegetation index, and yearly 0.05o, 500m land cover types. More data will be added in the near future. By combining atmospheric and oceanic data products in the Giovanni system, it is possible to do further analyses of environmental and climate changes associated with the land, ocean, and atmosphere. This presentation demonstrates exploring land products in the Giovanni system with sample case scenarios.

  11. An iterative multidisciplinary analysis for rotor blade shape determination

    NASA Technical Reports Server (NTRS)

    Mahajan, Aparajit J.; Stefko, George L.

    1993-01-01

    A CFD solver called ADPAC-APES is coupled with a NASTRAN structural analysis and a MARC thermal/heat transfer analysis to determine rotor blade shape. Nonlinear blade displacements due to centrifugal loads, aerodynamic pressures, and nonuniform temperature distribution are determined simultaneously. The effect of blade displacements on aerodynamic pressures and temperatures is then analyzed. These calculations are iterated till a steady state is reached across all the disciplines. This iterative procedure is applied to a ducted fan rotor blade and the manufactured shape is determined from a given operating shape. Effect of a part-span shroud on blade deflections is also analyzed.

  12. Multidisciplinary Analysis of Cyclophilin a Function in Human Breast Cancer

    DTIC Science & Technology

    2009-03-01

    in the ICD of the PRLr and Jak2 by EPR spectroscopy analysis (Months 12-36). 4 c. Functional characterization of the putative proline residues that...relationships of this protein complex when analyzed with data from crystallography and EPR spectroscopy as proposed in Aim #2. Task 2...siRNA knockdown system (Months 12-18). c. In vitro testing of the effects of manipulating CypA levels and activity on PRLr signaling. (Months 12-36

  13. Multidisciplinary Analysis of Cyclophilin A Function in Human Breast Cancer

    DTIC Science & Technology

    2011-03-01

    the PRLr and Jak2 by EPR spectroscopy analysis (Months 12-36). c. Functional characterization of the putative proline residues that are the target of...and generation of synthetic antibodies that neutralize CypA activity. To test the functional effects of altering the structure of the PRLr complex by...have successfully developed several synthetic antibodies, which exhibit nanomolar affinities toward CypA. Experiments are currently underway to test

  14. Multidisciplinary optimization

    SciTech Connect

    Dennis, J.; Lewis, R.M.; Cramer, E.J.; Frank, P.M.; Shubin, G.R.

    1994-12-31

    This talk will use aeroelastic design and reservoir characterization as examples to introduce some approaches to MDO, or Multidisciplinary Optimization. This problem arises especially in engineering design, where it is considered of paramount importance in today`s competitive global business climate. It is interesting to an optimizer because the constraints involve coupled dissimilar systems of parameterized partial differential equations each arising from a different discipline, like structural analysis, computational fluid dynamics, etc. Usually, these constraints are accessible only through pde solvers rather than through algebraic residual calculations as we are used to having. Thus, just finding a multidisciplinary feasible point is a daunting task. Many such problems have discrete variable disciplines, multiple objectives, and other challenging features. After discussing some interesting practical features of the design problem, we will give some standard ways to formulate the problem as well as some novel ways that lend themselves to divide-and-conquer parallelism.

  15. Methodology for analysis and simulation of large multidisciplinary problems

    NASA Technical Reports Server (NTRS)

    Russell, William C.; Ikeda, Paul J.; Vos, Robert G.

    1989-01-01

    The Integrated Structural Modeling (ISM) program is being developed for the Air Force Weapons Laboratory and will be available for Air Force work. Its goal is to provide a design, analysis, and simulation tool intended primarily for directed energy weapons (DEW), kinetic energy weapons (KEW), and surveillance applications. The code is designed to run on DEC (VMS and UNIX), IRIS, Alliant, and Cray hosts. Several technical disciplines are included in ISM, namely structures, controls, optics, thermal, and dynamics. Four topics from the broad ISM goal are discussed. The first is project configuration management and includes two major areas: the software and database arrangement and the system model control. The second is interdisciplinary data transfer and refers to exchange of data between various disciplines such as structures and thermal. Third is a discussion of the integration of component models into one system model, i.e., multiple discipline model synthesis. Last is a presentation of work on a distributed processing computing environment.

  16. Characterizing the peritumoral brain zone in glioblastoma: a multidisciplinary analysis.

    PubMed

    Lemée, Jean-Michel; Clavreul, Anne; Aubry, Marc; Com, Emmanuelle; de Tayrac, Marie; Eliat, Pierre-Antoine; Henry, Cécile; Rousseau, Audrey; Mosser, Jean; Menei, Philippe

    2015-03-01

    Glioblastoma (GB) is the most frequent and aggressive type of primary brain tumor. Recurrences are mostly located at the margin of the resection cavity in the peritumoral brain zone (PBZ). Although it is widely believed that infiltrative tumor cells in this zone are responsible for GB recurrence, few studies have examined this zone. In this study, we analyzed PBZ left after surgery with a variety of techniques including radiology, histopathology, flow cytometry, genomic, transcriptomic, proteomic, and primary cell cultures. The resulting PBZ profiles were compared with those of the GB tumor zone and normal brain samples to identify characteristics specific to the PBZ. We found that tumor cell infiltration detected by standard histological analysis was present in almost one third of PBZ taken from an area that was considered normal both on standard MRI and by the neurosurgeon under an operating microscope. The panel of techniques used in this study show that the PBZ, similar to the tumor zone itself, is characterized by substantial inter-patient heterogeneity, which makes it difficult to identify representative markers. Nevertheless, we identified specific alterations in the PBZ such as the presence of selected tumor clones and stromal cells with tumorigenic and angiogenic properties. The study of GB-PBZ is a growing field of interest and this region needs to be characterized further. This will facilitate the development of new, targeted therapies for patients with GB and the development of approaches to refine the per-operative evaluation of the PBZ to optimize the surgical resection of the tumor.

  17. NASA Subsonic Rotary Wing Project-Multidisciplinary Analysis and Technology Development: Overview

    NASA Technical Reports Server (NTRS)

    Yamauchi, Gloria K.

    2009-01-01

    This slide presentation reviews the objectives of the Multidisciplinary Analysis and Technology Development (MDATD) in the Subsonic Rotary Wing project. The objectives are to integrate technologies and analyses to enable advanced rotorcraft and provide a roadmap to guide Level 1 and 2 research. The MDATD objectives will be met by conducting assessments of advanced technology benefits, developing new or enhanced design tools, and integrating Level 2 discipline technologies to develop and enable system-level analyses and demonstrations.

  18. The concept of global monsoon applied to the last glacial maximum: A multi-model analysis

    NASA Astrophysics Data System (ADS)

    Jiang, Dabang; Tian, Zhiping; Lang, Xianmei; Kageyama, Masa; Ramstein, Gilles

    2015-10-01

    The last glacial maximum (LGM, ca. 21,000 years ago) has been extensively investigated for better understanding of past glacial climates. Global-scale monsoon changes, however, have not yet been determined. In this study, we examine global monsoon area (GMA) and precipitation (GMP) as well as GMP intensity (GMPI) at the LGM using the experiments of 17 climate models chosen from the Paleoclimate Modelling Intercomparison Project (PMIP) according to their ability to reproduce the present global monsoon climate. Compared to the reference period (referring to the present day, ca. 1985, for three atmospheric plus two atm-slab ocean models and the pre-industrial period, ca. 1750, for 12 fully coupled atmosphere-ocean or atmosphere-ocean-vegetation models), the LGM monsoon area increased over land and decreased over the oceans. The boreal land monsoon areas generally shifted southward, while the northern boundary of land monsoon areas retreated southward over southern Africa and South America. Both the LGM GMP and GMPI decreased in most of the models. The GMP decrease mainly resulted from the reduced monsoon precipitation over the oceans, while the GMPI decrease was derived from the weakened intensity of monsoon precipitation over land and the boreal ocean. Quantitatively, the LGM GMP deficit was due to, first, the GMA reduction and, second, the GMPI weakening. In response to the LGM large ice sheets and lower greenhouse gas concentrations in the atmosphere, the global surface and tropospheric temperatures cooled, the boreal summer meridional temperature gradient increased, and the summer land-sea thermal contrast at 40°S - 70°N decreased. These are the underlying dynamic mechanisms for the LGM monsoon changes. Qualitatively, simulations agree with reconstructions in all land monsoon areas except in the western part of northern Australia where disagreements occur and in South America and the southern part of southern Africa where there is uncertainty in reconstructions

  19. Multidisciplinary Tool for Systems Analysis of Planetary Entry, Descent, and Landing

    NASA Technical Reports Server (NTRS)

    Samareh, Jamshid A.

    2011-01-01

    Systems analysis of a planetary entry (SAPE), descent, and landing (EDL) is a multidisciplinary activity in nature. SAPE improves the performance of the systems analysis team by automating and streamlining the process, and this improvement can reduce the errors that stem from manual data transfer among discipline experts. SAPE is a multidisciplinary tool for systems analysis of planetary EDL for Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Titan. It performs EDL systems analysis for any planet, operates cross-platform (i.e., Windows, Mac, and Linux operating systems), uses existing software components and open-source software to avoid software licensing issues, performs low-fidelity systems analysis in one hour on a computer that is comparable to an average laptop, and keeps discipline experts in the analysis loop. SAPE uses Python, a platform-independent, open-source language, for integration and for the user interface. Development has relied heavily on the object-oriented programming capabilities that are available in Python. Modules are provided to interface with commercial and government off-the-shelf software components (e.g., thermal protection systems and finite-element analysis). SAPE currently includes the following analysis modules: geometry, trajectory, aerodynamics, aerothermal, thermal protection system, and interface for structural sizing.

  20. IMAT (Integrated Multidisciplinary Analysis Tool) user's guide for the VAX/VMS computer

    NASA Technical Reports Server (NTRS)

    Meissner, Frances T. (Editor)

    1988-01-01

    The Integrated Multidisciplinary Analysis Tool (IMAT) is a computer software system for the VAX/VMS computer developed at the Langley Research Center. IMAT provides researchers and analysts with an efficient capability to analyze satellite control systems influenced by structural dynamics. Using a menu-driven executive system, IMAT leads the user through the program options. IMAT links a relational database manager to commercial and in-house structural and controls analysis codes. This paper describes the IMAT software system and how to use it.

  1. Analysis of estuarine colour components during non-monsoon period through Ocean Colour Monitor

    NASA Astrophysics Data System (ADS)

    Menon, H. B.; Lotliker, A. A.; Nayak, S. R.

    2006-02-01

    Simultaneous acquisition of water samples, radiance and irradiance measurements were carried out from 40 stations in the Mandovi-Zuari estuaries during February to May 2002. From the samples collected, inherent and apparent optical properties (IOP and AOP) such as absorption coefficient ( a), upwelling diffuse attenuation coefficient ( ku) and subsurface reflectance ( R) were derived. Using these optical properties, radiative transfer at each water column is examined. On the basis of the radiative transfer outcome, band-ratio algorithms are derived for three optically active substances (OAS), viz, chlorophyll- a, suspended sediment and coloured dissolved organic matter (CDOM). The respective algorithms are 670/555, 490/670 and 412/670 nm for chlorophyll- a, suspended sediment and CDOM. These algorithms are applied to Ocean Colour Monitor (OCM), onboard Indian Remote Sensing Satellite (IRS)-Polar Satellite Launch Vehicle (P4), scenes (digital data), to synoptically analyze these OAS. The synoptic analysis of OAS revealed different hydrodynamic characteristics of the estuaries during non-monsoon seasons.

  2. A Multidisciplinary Tool for Systems Analysis of Planetary Entry, Descent, and Landing (SAPE)

    NASA Technical Reports Server (NTRS)

    Samareh, Jamshid A.

    2009-01-01

    SAPE is a Python-based multidisciplinary analysis tool for systems analysis of planetary entry, descent, and landing (EDL) for Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Titan. The purpose of SAPE is to provide a variable-fidelity capability for conceptual and preliminary analysis within the same framework. SAPE includes the following analysis modules: geometry, trajectory, aerodynamics, aerothermal, thermal protection system, and structural sizing. SAPE uses the Python language-a platform-independent open-source software for integration and for the user interface. The development has relied heavily on the object-oriented programming capabilities that are available in Python. Modules are provided to interface with commercial and government off-the-shelf software components (e.g., thermal protection systems and finite-element analysis). SAPE runs on Microsoft Windows and Apple Mac OS X and has been partially tested on Linux.

  3. Analysis of the seasonal ozone budget and the impact of the summer monsoon on the northeastern Qinghai-Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Zhu, Bin; Hou, Xuewei; Kang, Hanqing

    2016-02-01

    Seasonal variations in ozone (O3) and the impact of the East Asian summer monsoon at Mount Waliguan (WLG) in the northeastern Qinghai-Tibetan Plateau (TP) and in the surrounding regions were analyzed for 1997-2007 using a global chemical transport model coupled with O3 tagging simulations. The model-simulated O3 and its precursors agreed well with observed values. An O3 budget analysis combined with O3 tagging results implied that photochemistry over the TP and long-range transport of O3 from East Asia, Europe, and Africa were responsible for the surface O3 summer maximum at WLG. In June, the contribution of O3 from the TP was 11.8 ppbv, and the total contribution of O3 transport from eastern China, Japan, Korean Peninsula, Europe, and Africa was 22.7 ppbv. At 400 mb, the O3 exports from the stratosphere, Europe, Africa, and the Americas seemed to be the main sources of O3 at WLG. The contributions to surface O3 from deep convection process and lightning-induced photochemistry at WLG were both low in summer and are unlikely to be the key processes or contributors for the O3 peak. At several mountain sites in southeast East Asia, the increasing summer monsoon index was related to a decreasing trend for O3 from spring onward at Mount Tai and Mount Huang. At Mount Hua and WLG, regional O3 accumulated over the monsoon's northernmost marginal zone under the influence of the East Asian summer monsoon and TP thermal circulation; this is most likely a key reason for the O3 summer maxima.

  4. Multidisciplinary High-Fidelity Analysis and Optimization of Aerospace Vehicles. Part 1; Formulation

    NASA Technical Reports Server (NTRS)

    Walsh, J. L.; Townsend, J. C.; Salas, A. O.; Samareh, J. A.; Mukhopadhyay, V.; Barthelemy, J.-F.

    2000-01-01

    An objective of the High Performance Computing and Communication Program at the NASA Langley Research Center is to demonstrate multidisciplinary shape and sizing optimization of a complete aerospace vehicle configuration by using high-fidelity, finite element structural analysis and computational fluid dynamics aerodynamic analysis in a distributed, heterogeneous computing environment that includes high performance parallel computing. A software system has been designed and implemented to integrate a set of existing discipline analysis codes, some of them computationally intensive, into a distributed computational environment for the design of a highspeed civil transport configuration. The paper describes the engineering aspects of formulating the optimization by integrating these analysis codes and associated interface codes into the system. The discipline codes are integrated by using the Java programming language and a Common Object Request Broker Architecture (CORBA) compliant software product. A companion paper presents currently available results.

  5. The Component Packaging Problem: A Vehicle for the Development of Multidisciplinary Design and Analysis Methodologies

    NASA Technical Reports Server (NTRS)

    Fadel, Georges; Bridgewood, Michael; Figliola, Richard; Greenstein, Joel; Kostreva, Michael; Nowaczyk, Ronald; Stevenson, Steve

    1999-01-01

    This report summarizes academic research which has resulted in an increased appreciation for multidisciplinary efforts among our students, colleagues and administrators. It has also generated a number of research ideas that emerged from the interaction between disciplines. Overall, 17 undergraduate students and 16 graduate students benefited directly from the NASA grant: an additional 11 graduate students were impacted and participated without financial support from NASA. The work resulted in 16 theses (with 7 to be completed in the near future), 67 papers or reports mostly published in 8 journals and/or presented at various conferences (a total of 83 papers, presentations and reports published based on NASA inspired or supported work). In addition, the faculty and students presented related work at many meetings, and continuing work has been proposed to NSF, the Army, Industry and other state and federal institutions to continue efforts in the direction of multidisciplinary and recently multi-objective design and analysis. The specific problem addressed is component packing which was solved as a multi-objective problem using iterative genetic algorithms and decomposition. Further testing and refinement of the methodology developed is presently under investigation. Teaming issues research and classes resulted in the publication of a web site, (http://design.eng.clemson.edu/psych4991) which provides pointers and techniques to interested parties. Specific advantages of using iterative genetic algorithms, hurdles faced and resolved, and institutional difficulties associated with multi-discipline teaming are described in some detail.

  6. OpenMDAO: Framework for Flexible Multidisciplinary Design, Analysis and Optimization Methods

    NASA Technical Reports Server (NTRS)

    Heath, Christopher M.; Gray, Justin S.

    2012-01-01

    The OpenMDAO project is underway at NASA to develop a framework which simplifies the implementation of state-of-the-art tools and methods for multidisciplinary design, analysis and optimization. Foremost, OpenMDAO has been designed to handle variable problem formulations, encourage reconfigurability, and promote model reuse. This work demonstrates the concept of iteration hierarchies in OpenMDAO to achieve a flexible environment for supporting advanced optimization methods which include adaptive sampling and surrogate modeling techniques. In this effort, two efficient global optimization methods were applied to solve a constrained, single-objective and constrained, multiobjective version of a joint aircraft/engine sizing problem. The aircraft model, NASA's nextgeneration advanced single-aisle civil transport, is being studied as part of the Subsonic Fixed Wing project to help meet simultaneous program goals for reduced fuel burn, emissions, and noise. This analysis serves as a realistic test problem to demonstrate the flexibility and reconfigurability offered by OpenMDAO.

  7. Structural Model Tuning Capability in an Object-Oriented Multidisciplinary Design, Analysis, and Optimization Tool

    NASA Technical Reports Server (NTRS)

    Lung, Shun-fat; Pak, Chan-gi

    2008-01-01

    Updating the finite element model using measured data is a challenging problem in the area of structural dynamics. The model updating process requires not only satisfactory correlations between analytical and experimental results, but also the retention of dynamic properties of structures. Accurate rigid body dynamics are important for flight control system design and aeroelastic trim analysis. Minimizing the difference between analytical and experimental results is a type of optimization problem. In this research, a multidisciplinary design, analysis, and optimization [MDAO] tool is introduced to optimize the objective function and constraints such that the mass properties, the natural frequencies, and the mode shapes are matched to the target data as well as the mass matrix being orthogonalized.

  8. Structural Model Tuning Capability in an Object-Oriented Multidisciplinary Design, Analysis, and Optimization Tool

    NASA Technical Reports Server (NTRS)

    Lung, Shun-fat; Pak, Chan-gi

    2008-01-01

    Updating the finite element model using measured data is a challenging problem in the area of structural dynamics. The model updating process requires not only satisfactory correlations between analytical and experimental results, but also the retention of dynamic properties of structures. Accurate rigid body dynamics are important for flight control system design and aeroelastic trim analysis. Minimizing the difference between analytical and experimental results is a type of optimization problem. In this research, a multidisciplinary design, analysis, and optimization (MDAO) tool is introduced to optimize the objective function and constraints such that the mass properties, the natural frequencies, and the mode shapes are matched to the target data as well as the mass matrix being orthogonalized.

  9. Detailed Analysis of Indian Summer Monsoon Rainfall Processes with Modern/High-Quality Satellite Observations

    NASA Technical Reports Server (NTRS)

    Smith, Eric A.; Kuo, Kwo-Sen; Mehta, Amita V.; Yang, Song

    2007-01-01

    We examine, in detail, Indian Summer Monsoon rainfall processes using modernhigh quality satellite precipitation measurements. The focus here is on measurements derived from three NASA cloud and precipitation satellite missionslinstruments (TRMM/PR&TMI, AQUNAMSRE, and CLOUDSATICPR), and a fourth TRMM Project-generated multi-satellite precipitation measurement dataset (viz., TRMM standard algorithm 3b42) -- all from a period beginning in 1998 up to the present. It is emphasized that the 3b42 algorithm blends passive microwave (PMW) radiometer-based precipitation estimates from LEO satellites with infi-ared (IR) precipitation estimates from a world network of CEO satellites (representing -15% of the complete space-time coverage) All of these observations are first cross-calibrated to precipitation estimates taken from standard TRMM combined PR-TMI algorithm 2b31, and second adjusted at the large scale based on monthly-averaged rain-gage measurements. The blended approach takes advantage of direct estimates of precipitation from the PMW radiometerequipped LEO satellites -- but which suffer fi-om sampling limitations -- in combination with less accurate IR estimates from the optical-infrared imaging cameras on GEO satellites -- but which provide continuous diurnal sampling. The advantages of the current technologies are evident in the continuity and coverage properties inherent to the resultant precipitation datasets that have been an outgrowth of these stable measuring and retrieval technologies. There is a wealth of information contained in the current satellite measurements of precipitation regarding the salient precipitation properties of the Indian Summer Monsoon. Using different datasets obtained from the measuring systems noted above, we have analyzed the observations cast in the form of: (1) spatially distributed means and variances over the hierarchy of relevant time scales (hourly I diurnally, daily, monthly, seasonally I intra-seasonally, and inter

  10. The turbulence underside of the West African Monsoon

    NASA Astrophysics Data System (ADS)

    Lothon, M.; Lohou, F.; Saïd, F.; Campistron, B.; Canut, G.; Couvreux, F.; Durand, P.; Kalapureddy, M. C.; Lee, Y.; Madougou, S.; Serça, D.

    2009-09-01

    We present an experimental analysis of the sahelian Planetary Boundary Layer (PBL) processes in the context of the AMMA (African Monsoon Multidisciplinary Analysis) program and its extensive observational deployment in 2006. From May to October, two opposite flows are interacting in the first 5 thousands m over surface in Sahel: the moist southerly monsoon flow and the overlying northeasterly Saharan Air Layer (SAL) in which the African Easterly Jet (AEJ) is developing, generated by the contrast of surface moisture and temperature between Sahara and the Gulf of Guinea. Until the monsoon onset in mid-July, the low troposphere is slowly moistening through advection from the Guinea Gulf by the monsoon flow, especially during the night. During the day, the dry convection occurring within the PBL vertically redistributes part of the water vapour. After the onset, deep convection occurs much more frequently and the role played by the PBL completely changes. The relative position of the interface between monsoon and SAL and the PBL top inversion is crucial for the nature of the interaction and its impact on scalars, especially water vapour. We consider the role of the PBL processes in this context, and focus on four main aspects: (1) the diurnal cycle of the low troposphere, (2) the interaction between the PBL and the AEJ, (3) the entrainment at the PBL top (4) the impact of the PBL processes at surface. We base our analysis on long term profilers, radiosondes, and surface flux data, short term aircraft turbulence measurements made during the Special Observing Periods and Large Eddy Simulation. The network of wind profilers enables us to study the large scale circulation and highlight the consistence and extent of the nocturnal jet, and the importance of the diurnal cycle of the low troposphere for the West African Monsoon. During daytime, both the wind within the monsoon flow and the AEJ windspeed in the overlying SAL decrease, due to turbulent mixing within the PBL and

  11. Roadmap to the multidisciplinary design analysis and optimisation of wind energy systems

    NASA Astrophysics Data System (ADS)

    Sanchez Perez-Moreno, S.; Zaaijer, M. B.; Bottasso, C. L.; Dykes, K.; Merz, K. O.; Réthoré, P.-E.; Zahle, F.

    2016-09-01

    A research agenda is described to further encourage the application of Multidisciplinary Design Analysis and Optimisation (MDAO) methodologies to wind energy systems. As a group of researchers closely collaborating within the International Energy Agency (IEA) Wind Task 37 for Wind Energy Systems Engineering: Integrated Research, Design and Development, we have identified challenges that will be encountered by users building an MDAO framework. This roadmap comprises 17 research questions and activities recognised to belong to three research directions: model fidelity, system scope and workflow architecture. It is foreseen that sensible answers to all these questions will enable to more easily apply MDAO in the wind energy domain. Beyond the agenda, this work also promotes the use of systems engineering to design, analyse and optimise wind turbines and wind farms, to complement existing compartmentalised research and design paradigms.

  12. The Indian Summer Monsoon onset revisited: new approach based on the analysis of historical wind observations

    NASA Astrophysics Data System (ADS)

    Ordoñez, Paulina; Gallego, David; Ribera, Pedro; Peña-Ortiz, Cristina; Garcia-Herrera, Ricardo; Vega, Inmaculada; Gómez, Francisco de Paula

    2016-04-01

    The Indian Summer Monsoon onset is one of the meteorological events most anticipated in the world. Due to its relevance for the population, the India Meteorological Department has dated the onset over the southern tip of the Indian Peninsula (Kerala) since 1901. The traditional method to date the onset was based in the judgment of skilled meteorologist and because of this, the method was considered subjective and not adequate for the study of long-term changes in the onset. A new method for determining the monsoon onset based solely on objective criteria has been in use since 2006. Unfortunately, the new method relies -among other variables- on OLR measurements. This requirement impedes the construction of an objective onset series before the satellite era. An alternative approach to establish the onset by objective methods is the use of the wind field. During the last decade, some works have demonstrated that the changes in the wind direction in some areas of the Indian Ocean can be used to determine the monsoon onset rather precisely. However, this method requires precise wind observations over a large oceanic area which has limited the periods covered for such kind of indices to those of the reanalysis products. In this work we present a new approach to track the Indian monsoon onset based solely on historical wind direction measurements taken onboard ships. Our new series provides an objective record of the onset since the last decade of the 19th century and perhaps more importantly, it can incorporate any new historical wind record not yet known in order to extend the series length. The new series captures quite precisely the rapid precipitation increase associated to the monsoon onset, correlates well with previous approaches and it is robust against anomalous (bogus) onsets. Although no significant trends in the onset date were detected, a tendency to later than average onsets during the 1900-1925 and 1970-1990 periods and earlier than average onsets between

  13. Eocene monsoons

    NASA Astrophysics Data System (ADS)

    Huber, Matthew; Goldner, Aaron

    2012-01-01

    A prominent example of climate-tectonic coupling is the Asian monsoon and the uplift of the Tibetan Plateau. Here we review some of what is known about the history of the monsoon, within a global context and present results from fully coupled Eocene simulations in which Tibetan Plateau height is varied. Peak elevations were doubled from 2000 m to 4000 m whereas mean elevations increased from 750 to 1500 m. The fully coupled Eocene simulations show that introducing a higher Tibetan Plateau into Asian topography intensifies rainfall over southwest Asia, but induces drying over and behind the Plateau. This atmospheric response is controlled by increases in heating over the Plateau region which drives increases in moisture convergence inducing shifts in lower level atmospheric moisture flux. With Eocene boundary conditions aspects of the canonical response from prior work remain the same: cooling over the uplifted region, a large stationary wave response emanating from the plateau and extending into North America, and a large increase in precipitation in summer in the regions with strongest relief, with a rain shadow behind it. But some important local responses are different from similar studies with modern boundary conditions, such as a warming behind the uplifted mountains, and southward advection of warm, moist air from Paratethys onto the Plateau. These results demonstrate that simulations with fully interactive ocean-atmosphere coupled models with a realistic history of paleogeographic boundary conditions will increase the realism of the resulting climatic simulations and increase the body of available proxy evidence for comparison. More generally we find that a global monsoon distribution of precipitation exists in the Eocene regardless of Tibetan Plateau height. Changing Plateau height has minor global impacts, which include a slight drying of midlatitude and cooling of the North Pacific. The results are robust to changes in climate model resolution and

  14. Extraction and prediction of indices for monsoon intraseasonal oscillations: an approach based on nonlinear Laplacian spectral analysis

    NASA Astrophysics Data System (ADS)

    Sabeerali, C. T.; Ajayamohan, R. S.; Giannakis, Dimitrios; Majda, Andrew J.

    2017-01-01

    An improved index for real-time monitoring and forecast verification of monsoon intraseasonal oscillations (MISOs) is introduced using the recently developed nonlinear Laplacian spectral analysis (NLSA) technique. Using NLSA, a hierarchy of Laplace-Beltrami (LB) eigenfunctions are extracted from unfiltered daily rainfall data from the Global Precipitation Climatology Project over the south Asian monsoon region. Two modes representing the full life cycle of the northeastward-propagating boreal summer MISO are identified from the hierarchy of LB eigenfunctions. These modes have a number of advantages over MISO modes extracted via extended empirical orthogonal function analysis including higher memory and predictability, stronger amplitude and higher fractional explained variance over the western Pacific, Western Ghats, and adjoining Arabian Sea regions, and more realistic representation of the regional heat sources over the Indian and Pacific Oceans. Real-time prediction of NLSA-derived MISO indices is demonstrated via extended-range hindcasts based on NCEP Coupled Forecast System version 2 operational output. It is shown that in these hindcasts the NLSA MISO indices remain predictable out to ˜ 3 weeks.

  15. Development of Response Surface Models for Rapid Analysis & Multidisciplinary Optimization of Launch Vehicle Design Concepts

    NASA Technical Reports Server (NTRS)

    Unal, Resit

    1999-01-01

    Multdisciplinary design optimization (MDO) is an important step in the design and evaluation of launch vehicles, since it has a significant impact on performance and lifecycle cost. The objective in MDO is to search the design space to determine the values of design parameters that optimize the performance characteristics subject to system constraints. Vehicle Analysis Branch (VAB) at NASA Langley Research Center has computerized analysis tools in many of the disciplines required for the design and analysis of launch vehicles. Vehicle performance characteristics can be determined by the use of these computerized analysis tools. The next step is to optimize the system performance characteristics subject to multidisciplinary constraints. However, most of the complex sizing and performance evaluation codes used for launch vehicle design are stand-alone tools, operated by disciplinary experts. They are, in general, difficult to integrate and use directly for MDO. An alternative has been to utilize response surface methodology (RSM) to obtain polynomial models that approximate the functional relationships between performance characteristics and design variables. These approximation models, called response surface models, are then used to integrate the disciplines using mathematical programming methods for efficient system level design analysis, MDO and fast sensitivity simulations. A second-order response surface model of the form given has been commonly used in RSM since in many cases it can provide an adequate approximation especially if the region of interest is sufficiently limited.

  16. STARS: An Integrated, Multidisciplinary, Finite-Element, Structural, Fluids, Aeroelastic, and Aeroservoelastic Analysis Computer Program

    NASA Technical Reports Server (NTRS)

    Gupta, K. K.

    1997-01-01

    A multidisciplinary, finite element-based, highly graphics-oriented, linear and nonlinear analysis capability that includes such disciplines as structures, heat transfer, linear aerodynamics, computational fluid dynamics, and controls engineering has been achieved by integrating several new modules in the original STARS (STructural Analysis RoutineS) computer program. Each individual analysis module is general-purpose in nature and is effectively integrated to yield aeroelastic and aeroservoelastic solutions of complex engineering problems. Examples of advanced NASA Dryden Flight Research Center projects analyzed by the code in recent years include the X-29A, F-18 High Alpha Research Vehicle/Thrust Vectoring Control System, B-52/Pegasus Generic Hypersonics, National AeroSpace Plane (NASP), SR-71/Hypersonic Launch Vehicle, and High Speed Civil Transport (HSCT) projects. Extensive graphics capabilities exist for convenient model development and postprocessing of analysis results. The program is written in modular form in standard FORTRAN language to run on a variety of computers, such as the IBM RISC/6000, SGI, DEC, Cray, and personal computer; associated graphics codes use OpenGL and IBM/graPHIGS language for color depiction. This program is available from COSMIC, the NASA agency for distribution of computer programs.

  17. Object-Oriented Multi-Disciplinary Design, Analysis, and Optimization Tool

    NASA Technical Reports Server (NTRS)

    Pak, Chan-gi

    2011-01-01

    An Object-Oriented Optimization (O3) tool was developed that leverages existing tools and practices, and allows the easy integration and adoption of new state-of-the-art software. At the heart of the O3 tool is the Central Executive Module (CEM), which can integrate disparate software packages in a cross platform network environment so as to quickly perform optimization and design tasks in a cohesive, streamlined manner. This object-oriented framework can integrate the analysis codes for multiple disciplines instead of relying on one code to perform the analysis for all disciplines. The CEM was written in FORTRAN and the script commands for each performance index were submitted through the use of the FORTRAN Call System command. In this CEM, the user chooses an optimization methodology, defines objective and constraint functions from performance indices, and provides starting and side constraints for continuous as well as discrete design variables. The structural analysis modules such as computations of the structural weight, stress, deflection, buckling, and flutter and divergence speeds have been developed and incorporated into the O3 tool to build an object-oriented Multidisciplinary Design, Analysis, and Optimization (MDAO) tool.

  18. Variability and risk analysis of Hong Kong air quality based on Monsoon and El Niño conditions

    NASA Astrophysics Data System (ADS)

    Kim, Jong-Suk; Zhou, Wen; Cheung, Ho Nam; Chow, Chak Hang

    2013-03-01

    This study presents an exploratory analysis aimed at improving understanding of the variability of Hong Kong air quality associated with different climate conditions. Significantly negative correlations were found when Niño 3 led particulate matter ⩽10 μm PM10) and NO2 by 2-3 months over the Hong Kong territory, while the other pollutants (e.g., O3, SO2) showed modest correlations. A significant decreasing trend in visibility was observed during the autumn and winter, which has potential implications for the air-quality degradation and the endangerment of human health in Hong Kong. In an El Niño summer, the visibility was relatively better, while visibility in other seasons was diminished. On the other hand, in La Niña events, significant changes occurred in visibility in winter and autumn. Air pollution indices were less sensitive to the South China Summer Monsoon (SCSM), but a relatively high correlation existed between the East Asian Winter Monsoon (EAWM) and air pollutants. Rainfall was lower during most of the strong EAWM years compared to the weak years. This result suggests that the pollutants that accumulate in Hong Kong are not easy to wash out, so concentrations remain at a higher level. Finally, based on the conditional Air Pollution Index (API) risk assessment, site-specific vulnerabilities were analyzed to facilitate the development of the air-quality warning systems in Hong Kong.

  19. Getting a Cohesive Answer from a Common Start: Scalable Multidisciplinary Analysis through Transformation of a Systems Model

    NASA Technical Reports Server (NTRS)

    Cole, Bjorn; Chung, Seung

    2012-01-01

    One of the challenges of systems engineering is in working multidisciplinary problems in a cohesive manner. When planning analysis of these problems, system engineers must trade between time and cost for analysis quality and quantity. The quality often correlates with greater run time in multidisciplinary models and the quantity is associated with the number of alternatives that can be analyzed. The trade-off is due to the resource intensive process of creating a cohesive multidisciplinary systems model and analysis. Furthermore, reuse or extension of the models used in one stage of a product life cycle for another is a major challenge. Recent developments have enabled a much less resource-intensive and more rigorous approach than hand-written translation scripts between multi-disciplinary models and their analyses. The key is to work from a core systems model defined in a MOF-based language such as SysML and in leveraging the emerging tool ecosystem, such as Query/View/Transformation (QVT), from the OMG community. SysML was designed to model multidisciplinary systems. The QVT standard was designed to transform SysML models into other models, including those leveraged by engineering analyses. The Europa Habitability Mission (EHM) team has begun to exploit these capabilities. In one case, a Matlab/Simulink model is generated on the fly from a system description for power analysis written in SysML. In a more general case, symbolic analysis (supported by Wolfram Mathematica) is coordinated by data objects transformed from the systems model, enabling extremely flexible and powerful design exploration and analytical investigations of expected system performance.

  20. Analysis and evaluation of Observing System Simulation Experiments (OSSEs) forecast data for Indian summer monsoon

    NASA Astrophysics Data System (ADS)

    Deshpande, Medha; Mukhopadhyay, P.; Masutani, Michiko; Ma, Zaizhong; Riishojgaard, Lars Peter; Hardesty, Michael; Emmitt, Dave; Krishnamurti, T. N.; Goswami, B. N.

    2016-05-01

    An attempt is made here to evaluate the skill of forecast during boreal summer monsoon regime over the Indian region using the Observation Simulation System Experiment (OSSE) with Doppler Wind LIDAR (DWL) onboard International Space Station (ISS), assimilated in the initial condition. Through various techniques such as pattern correlation, root mean square error etc, we found that there is some positive impact of assimilating the DWL data on the forecast particularly at the lower tropospheric level. Impact on lowering the RMSE is seen for wind fields in the 850 and 500 hPa over Indian domain but not much impact is seen over larger domain. The moisture field and cloud also show marginal impact due to assimilation of DWL. This indicates that possibly due to lower spatial resolution of DWL data and more data gap over Indian and surrounding oceanic region, the impact on forecast is less. However, it shows the promise that monsoon being a convectively coupled system; increase in spatial data by DWL may better resolve the low level wind and subsequently the low level shear which is important for convection trigger in boundary layer.

  1. Cloud-radiation-precipitation associations over the Asian monsoon region: an observational analysis

    NASA Astrophysics Data System (ADS)

    Li, Jiandong; Wang, Wei-Chyung; Dong, Xiquan; Mao, Jiangyu

    2017-01-01

    This study uses 2001-2014 satellite observations and reanalyses to investigate the seasonal characteristics of Cloud Radiative Effects (CREs) and their associations with cloud fraction (CF) and precipitation over the Asian monsoon region (AMR) covering Eastern China (EC) and South Asia (SA). The CREs exhibit strong seasonal variations but show distinctly different relationships with CFs and precipitation over the two regions. For EC, the CREs is dominated by shortwave (SW) cooling, with an annual mean value of - 40 W m- 2 for net CRE, and peak in summer while the presence of extensive and opaque low-level clouds contributes to large Top-Of-Atmosphere (TOA) albedo (>0.5) in winter. For SA, a weak net CRE exists throughout the year due to in-phase compensation of SWCRE by longwave (LW) CRE associated with the frequent occurrence of high clouds. For the entire AMR, SWCRE strongly correlates with the dominant types of CFs, although the cloud vertical structure plays important role particularly in summer. The relationships between CREs and precipitation are stronger in SA than in EC, indicating the dominant effect of monsoon circulation in the former region. SWCRE over EC is only partly related to precipitation and shows distinctive regional variations. Further studies need to pay more attention to vertical distributions of cloud micro- and macro-physical properties, and associated precipitation systems over the AMR.

  2. Getting a Cohesive Answer from a Common Start: Scalable Multidisciplinary Analysis through Transformation of a System Model

    NASA Technical Reports Server (NTRS)

    Cole, Bjorn; Chung, Seung H.

    2012-01-01

    One of the challenges of systems engineering is in working multidisciplinary problems in a cohesive manner. When planning analysis of these problems, system engineers must tradeoff time and cost for analysis quality and quantity. The quality is associated with the fidelity of the multidisciplinary models and the quantity is associated with the design space that can be analyzed. The tradeoff is due to the resource intensive process of creating a cohesive multidisciplinary system model and analysis. Furthermore, reuse or extension of the models used in one stage of a product life cycle for another is a major challenge. Recent developments have enabled a much less resource-intensive and more rigorous approach than handwritten translation scripts or codes of multidisciplinary models and their analyses. The key is to work from a core system model defined in a MOF-based language such as SysML and in leveraging the emerging tool ecosystem, such as Query-View- Transform (QVT), from the OMG community. SysML was designed to model multidisciplinary systems and analyses. The QVT standard was designed to transform SysML models. The Europa Hability Mission (EHM) team has begun to exploit these capabilities. In one case, a Matlab/Simulink model is generated on the fly from a system description for power analysis written in SysML. In a more general case, a symbolic mathematical framework (supported by Wolfram Mathematica) is coordinated by data objects transformed from the system model, enabling extremely flexible and powerful tradespace exploration and analytical investigations of expected system performance.

  3. Phenology Analysis of Forest Vegetation to Environmental Variables during - and Post-Monsoon Seasons in Western Himalayan Region of India

    NASA Astrophysics Data System (ADS)

    Khare, S.; Latifi, H.; Ghosh, K.

    2016-06-01

    To assess the phenological changes in Moist Deciduous Forest (MDF) of western Himalayan region of India, we carried out NDVI time series analysis from 2013 to 2015 using Landsat 8 OLI data. We used the vegetation index differencing method to calculate the change in NDVI (NDVIchange) during pre and post monsoon seasons and these changes were used to assess the phenological behaviour of MDF by taking the effect of a set of environmental variables into account. To understand the effect of environmental variables on change in phenology, we designed a linear regression analysis with sample-based NDVIchange values as the response variable and elevation aspect, and Land Surface Temperature (LST) as explanatory variables. The Landsat-8 derived phenology transition stages were validated by calculating the phenology variation from Nov 2008 to April 2009 using Landsat-7 which has the same spatial resolution as Landsat-8. The Landsat-7 derived NDVI trajectories were plotted in accordance with MODIS derived phenology stages (from Nov 2008 to April 2009) of MDF. Results indicate that the Landsat -8 derived NDVI trajectories describing the phenology variation of MDF during spring, monsoon autumn and winter seasons agreed closely with Landsat-7 and MODIS derived phenology transition from Nov 2008 to April 2009. Furthermore, statistical analysis showed statistically significant correlations (p < 0.05) amongst the environmental variables and the NDVIchange between full greenness and maximum frequency stage of Onset of Greenness (OG) activity.. The major change in NDVI was observed in medium (600 to 650 m) and maximum (650 to 750 m) elevation areas. The change in LST showed also to be highly influential. The results of this study can be used for large scale monitoring of difficult-to-reach mountainous forests, with additional implications in biodiversity assessment. By means of a sufficient amount of available cloud-free imagery, detailed phenological trends across mountainous

  4. Multidisciplinary Modeling Software for Analysis, Design, and Optimization of HRRLS Vehicles

    NASA Technical Reports Server (NTRS)

    Spradley, Lawrence W.; Lohner, Rainald; Hunt, James L.

    2011-01-01

    The concept for Highly Reliable Reusable Launch Systems (HRRLS) under the NASA Hypersonics project is a two-stage-to-orbit, horizontal-take-off / horizontal-landing, (HTHL) architecture with an air-breathing first stage. The first stage vehicle is a slender body with an air-breathing propulsion system that is highly integrated with the airframe. The light weight slender body will deflect significantly during flight. This global deflection affects the flow over the vehicle and into the engine and thus the loads and moments on the vehicle. High-fidelity multi-disciplinary analyses that accounts for these fluid-structures-thermal interactions are required to accurately predict the vehicle loads and resultant response. These predictions of vehicle response to multi physics loads, calculated with fluid-structural-thermal interaction, are required in order to optimize the vehicle design over its full operating range. This contract with ResearchSouth addresses one of the primary objectives of the Vehicle Technology Integration (VTI) discipline: the development of high-fidelity multi-disciplinary analysis and optimization methods and tools for HRRLS vehicles. The primary goal of this effort is the development of an integrated software system that can be used for full-vehicle optimization. This goal was accomplished by: 1) integrating the master code, FEMAP, into the multidiscipline software network to direct the coupling to assure accurate fluid-structure-thermal interaction solutions; 2) loosely-coupling the Euler flow solver FEFLO to the available and proven aeroelasticity and large deformation (FEAP) code; 3) providing a coupled Euler-boundary layer capability for rapid viscous flow simulation; 4) developing and implementing improved Euler/RANS algorithms into the FEFLO CFD code to provide accurate shock capturing, skin friction, and heat-transfer predictions for HRRLS vehicles in hypersonic flow, 5) performing a Reynolds-averaged Navier-Stokes computation on an HRRLS

  5. A Multidisciplinary Performance Analysis of a Lifting-Body Single-Stage-to-Orbit Vehicle

    NASA Technical Reports Server (NTRS)

    Tartabini, Paul V.; Lepsch, Roger A.; Korte, J. J.; Wurster, Kathryn E.

    2000-01-01

    Lockheed Martin Skunk Works (LMSW) is currently developing a single-stage-to-orbit reusable launch vehicle called VentureStar(TM) A team at NASA Langley Research Center participated with LMSW in the screening and evaluation of a number of early VentureStar(TM) configurations. The performance analyses that supported these initial studies were conducted to assess the effect of a lifting body shape, linear aerospike engine and metallic thermal protection system (TPS) on the weight and performance of the vehicle. These performance studies were performed in a multidisciplinary fashion that indirectly linked the trajectory optimization with weight estimation and aerothermal analysis tools. This approach was necessary to develop optimized ascent and entry trajectories that met all vehicle design constraints. Significant improvements in ascent performance were achieved when the vehicle flew a lifting trajectory and varied the engine mixture ratio during flight. Also, a considerable reduction in empty weight was possible by adjusting the total oxidizer-to-fuel and liftoff thrust-to-weight ratios. However, the optimal ascent flight profile had to be altered to ensure that the vehicle could be trimmed in pitch using only the flow diverting capability of the aerospike engine. Likewise, the optimal entry trajectory had to be tailored to meet TPS heating rate and transition constraints while satisfying a crossrange requirement.

  6. Multidisciplinary framework for human reliability analysis with an application to errors of commission and dependencies

    SciTech Connect

    Barriere, M.T.; Luckas, W.J.; Wreathall, J.; Cooper, S.E.; Bley, D.C.; Ramey-Smith, A.

    1995-08-01

    Since the early 1970s, human reliability analysis (HRA) has been considered to be an integral part of probabilistic risk assessments (PRAs). Nuclear power plant (NPP) events, from Three Mile Island through the mid-1980s, showed the importance of human performance to NPP risk. Recent events demonstrate that human performance continues to be a dominant source of risk. In light of these observations, the current limitations of existing HRA approaches become apparent when the role of humans is examined explicitly in the context of real NPP events. The development of new or improved HRA methodologies to more realistically represent human performance is recognized by the Nuclear Regulatory Commission (NRC) as a necessary means to increase the utility of PRAS. To accomplish this objective, an Improved HRA Project, sponsored by the NRC`s Office of Nuclear Regulatory Research (RES), was initiated in late February, 1992, at Brookhaven National Laboratory (BNL) to develop an improved method for HRA that more realistically assesses the human contribution to plant risk and can be fully integrated with PRA. This report describes the research efforts including the development of a multidisciplinary HRA framework, the characterization and representation of errors of commission, and an approach for addressing human dependencies. The implications of the research and necessary requirements for further development also are discussed.

  7. Development of Multi-Disciplinary Finite Element Method Analysis Courses at California State University, Los Angeles

    NASA Technical Reports Server (NTRS)

    McKinney, John; Wu, Chivey

    1998-01-01

    The NASA Dryden Flight Research Center (DFRC) Partnership Awards Grant to California State University, Los Angeles (CSULA) has two primary goals that help to achieve NASA objectives. The overall objectives of the NASA Partnership Awards are to create opportunities for joint University NASA/Government sponsored research and related activities. One of the goals of the grant is to have university faculty researchers participate and contribute to the development of NASA technology that supports NASA goals for research and development (R&D) in Aeronautics and Astronautics. The other goal is technology transfer in the other direction, where NASA developed technology is made available to the general public and more specifically, targeted to industries that can profit from utilization of government developed technology. This years NASA Dryden Partnership Awards grant to CSULA entitled, "Computer Simulation of Multi-Disciplinary Engineering Systems", has two major tasks that satisfy overall NASA objectives. The first task conducts basic and applied research that contributes to technology development at the Dryden Flight Research Center. The second part of the grant provides for dissemination of NASA developed technology, by using the teaching environment created in the CSULA classroom. The second task and how this is accomplished is the topic of this paper. The NASA STARS (Structural Analysis Routines) computer simulation program is used at the Dryden center to support flight testing of high-performance experimental aircraft and to conduct research and development of new and advanced Aerospace technology.

  8. In our own image--a multidisciplinary qualitative analysis of medical education.

    PubMed

    Howe, Amanda; Billingham, Kate; Walters, Christina

    2002-11-01

    One aim of reform of undergraduate medical education is to achieve a better balance between an emphasis on scientific knowledge and an enhancement of desirable professional attitudes: for example, reducing the core curriculum in biochemistry in order to increase learning opportunities in ethics. This study was based on qualitative data collected from stakeholders involved in community- and primary care-based medical education. Its aim was to consider whether different participants agreed on the desired outcomes of basic medical training, and the contribution of community and primary care settings. Analysis of the data showed that the professional identity of the future doctor is contested, its goals reflective of the 'world view' of the stakeholder, and seen as being highly dependent on the contexts in which students learn. Themes which emerged suggest that medical education may not achieve its goals unless student experiences become less dominated by the context of secondary care and its predominantly technical practice of medicine, and more attention is paid to the personal development of the students. The discussion considers the implications for further reform, and emphasises the role of multidisciplinary tutoring in remodelling the world view of 'tomorrow's doctors'.

  9. Engineering Overview of a Multidisciplinary HSCT Design Framework Using Medium-Fidelity Analysis Codes

    NASA Technical Reports Server (NTRS)

    Weston, R. P.; Green, L. L.; Salas, A. O.; Samareh, J. A.; Townsend, J. C.; Walsh, J. L.

    1999-01-01

    An objective of the HPCC Program at NASA Langley has been to promote the use of advanced computing techniques to more rapidly solve the problem of multidisciplinary optimization of a supersonic transport configuration. As a result, a software system has been designed and is being implemented to integrate a set of existing discipline analysis codes, some of them CPU-intensive, into a distributed computational framework for the design of a High Speed Civil Transport (HSCT) configuration. The proposed paper will describe the engineering aspects of integrating these analysis codes and additional interface codes into an automated design system. The objective of the design problem is to optimize the aircraft weight for given mission conditions, range, and payload requirements, subject to aerodynamic, structural, and performance constraints. The design variables include both thicknesses of structural elements and geometric parameters that define the external aircraft shape. An optimization model has been adopted that uses the multidisciplinary analysis results and the derivatives of the solution with respect to the design variables to formulate a linearized model that provides input to the CONMIN optimization code, which outputs new values for the design variables. The analysis process begins by deriving the updated geometries and grids from the baseline geometries and grids using the new values for the design variables. This free-form deformation approach provides internal FEM (finite element method) grids that are consistent with aerodynamic surface grids. The next step involves using the derived FEM and section properties in a weights process to calculate detailed weights and the center of gravity location for specified flight conditions. The weights process computes the as-built weight, weight distribution, and weight sensitivities for given aircraft configurations at various mass cases. Currently, two mass cases are considered: cruise and gross take-off weight (GTOW

  10. Global aspects of monsoons

    NASA Technical Reports Server (NTRS)

    Murakami, T.

    1985-01-01

    Recent developments are studied in three areas of monsoon research: (1) global aspects of the monsoon onset, (2) the orographic influence of the Tibetan Plateau on the summer monsoon circulations, and (3) tropical 40 to 50 day oscillations. Reference was made only to those studies that are primarily based on FGGE Level IIIb data. A brief summary is given.

  11. Efficient Multidisciplinary Analysis Approach for Conceptual Design of Aircraft with Large Shape Change

    NASA Technical Reports Server (NTRS)

    Chwalowski, Pawel; Samareh, Jamshid A.; Horta, Lucas G.; Piatak, David J.; McGowan, Anna-Maria R.

    2009-01-01

    The conceptual and preliminary design processes for aircraft with large shape changes are generally difficult and time-consuming, and the processes are often customized for a specific shape change concept to streamline the vehicle design effort. Accordingly, several existing reports show excellent results of assessing a particular shape change concept or perturbations of a concept. The goal of the current effort was to develop a multidisciplinary analysis tool and process that would enable an aircraft designer to assess several very different morphing concepts early in the design phase and yet obtain second-order performance results so that design decisions can be made with better confidence. The approach uses an efficient parametric model formulation that allows automatic model generation for systems undergoing radical shape changes as a function of aerodynamic parameters, geometry parameters, and shape change parameters. In contrast to other more self-contained approaches, the approach utilizes off-the-shelf analysis modules to reduce development time and to make it accessible to many users. Because the analysis is loosely coupled, discipline modules like a multibody code can be easily swapped for other modules with similar capabilities. One of the advantages of this loosely coupled system is the ability to use the medium- to high-fidelity tools early in the design stages when the information can significantly influence and improve overall vehicle design. Data transfer among the analysis modules are based on an accurate and automated general purpose data transfer tool. In general, setup time for the integrated system presented in this paper is 2-4 days for simple shape change concepts and 1-2 weeks for more mechanically complicated concepts. Some of the key elements briefly described in the paper include parametric model development, aerodynamic database generation, multibody analysis, and the required software modules as well as examples for a telescoping wing

  12. Recent experience with multidisciplinary analysis and optimization in advanced aircraft design

    NASA Technical Reports Server (NTRS)

    Dollyhigh, Samuel M.; Sobieszczanski-Sobieski, Jaroslaw

    1990-01-01

    narrowed as more sophisticated methods are developed in the specialist's area of expertise. The results have been a decrease in the awareness of the impact of his decisions on other disciplines. This paper will outline the progress and problems encountered in the analysis, design, optimization sensitivity analysis, mathematical modeling, and configurations control and the means by which they are being solved. The breadth versus depth dilemma in analysis and design and the means for coping with that dilemma will be discussed. Finally, the all-important human aspects and the need for a new 'culture ' for doing business in an integrated, multidisciplinary design environment are discussed.

  13. Feedback of observed interannual vegetation change: a regional climate model analysis for the West African monsoon

    NASA Astrophysics Data System (ADS)

    Klein, Cornelia; Bliefernicht, Jan; Heinzeller, Dominikus; Gessner, Ursula; Klein, Igor; Kunstmann, Harald

    2016-06-01

    West Africa is a hot spot region for land-atmosphere coupling where atmospheric conditions and convective rainfall can strongly depend on surface characteristics. To investigate the effect of natural interannual vegetation changes on the West African monsoon precipitation, we implement satellite-derived dynamical datasets for vegetation fraction (VF), albedo and leaf area index into the Weather Research and Forecasting model. Two sets of 4-member ensembles with dynamic and static land surface description are used to extract vegetation-related changes in the interannual difference between August-September 2009 and 2010. The observed vegetation patterns retain a significant long-term memory of preceding rainfall patterns of at least 2 months. The interannual vegetation changes exhibit the strongest effect on latent heat fluxes and associated surface temperatures. We find a decrease (increase) of rainy hours over regions with higher (lower) VF during the day and the opposite during the night. The probability that maximum precipitation is shifted to nighttime (daytime) over higher (lower) VF is 12 % higher than by chance. We attribute this behaviour to horizontal circulations driven by differential heating. Over more vegetated regions, the divergence of moist air together with lower sensible heat fluxes hinders the initiation of deep convection during the day. During the night, mature convective systems cause an increase in the number of rainy hours over these regions. We identify this feedback in both water- and energy-limited regions of West Africa. The inclusion of observed dynamical surface information improved the spatial distribution of modelled rainfall in the Sahel with respect to observations, illustrating the potential of satellite data as a boundary constraint for atmospheric models.

  14. Analysis of cross-hemispheric influences on the monsoon trough and tropical cyclone genesis during FGGE and diurnal subsidence differences

    NASA Technical Reports Server (NTRS)

    Gray, W. M.; Lee, C. S.

    1985-01-01

    For a number of years our project has been studying the cross-equatorial (winter to summer hemisphere) processs that can lead to the day-to-day alterations in the strength of the monsoon trough. These processes are also related to the genesis and intensification of tropical storms. The cross-hemispheric processes that occurred during the FGGE year are currently being studied with the use of the ECMWF analysis. How the winter hemisphere can affect low level cold surge penetration across the equator following cold front passage, and how upper tropospheric anticyclones of the winter hemisphere can produce an intensification of a tropical cyclone of the opposite hemisphere is described. ECMWF analysis of the 00Z versus 12Z diurnal difference in the clear region (10 deg diameter) subsidence occurring in the subtropical Pacific Ocean during FGGE is presented. The general reliability of the FGGE ECMWF analysis with regard to the specification of the large scale structure of tropical cyclones is shown.

  15. On the association between pre-monsoon aerosol and all-India summer monsoon rainfall

    NASA Astrophysics Data System (ADS)

    Patil, S. D.; Preethi, B.; Bansod, S. D.; Singh, H. N.; Revadekar, J. V.; Munot, A. A.

    2013-09-01

    Summer monsoon rainfall which gives 75-90% of the annual rainfall plays vital role in Indian economy as the food grain production in India is very much dependent on the summer monsoon rainfall. It has been suggested by recent studies that aerosol loading over the Indian region plays significant role in modulating the monsoon circulation and consequent rainfall distribution over the Indian sub-continent. Increased industrialization and the increasing deforestation over past few decades probably cause a gradual increase in the aerosol concentration. A significant negative relationship between pre-monsoon (March-May i.e. MAM) aerosol loading over BOB and IGP regions and the forthcoming monsoon rainfall have been observed from the thorough analysis of the fifteen years (1997-2011) monthly Total Ozone Mapping Spectrometer (TOMS) Aerosol Index (AI) and All-India Summer Monsoon Rainfall (AISMR) data. Composite analysis revealed that AI anomalies during pre-monsoon season are negative for excess year and positive for deficient monsoon years over the Indian subcontinent, with strong variation over Bay of Bengal (BOB) and Indo-Gangetic Plain (IGP) regions from the month of March onwards. The correlation coefficients between AISMR and pre-monsoon AI over BOB and IGP regions are found to be negative and significant at 5% level. The study clearly brings out that the pre-monsoon aerosol loading over the BOB and IGP regions has a significant correlational link with the forthcoming monsoon intensity; however a further study of the aerosol properties and their feedback to the cloud microphysical properties is asked for establishing their causal linkage.

  16. The importance of a multidisciplinary approach for solid earth geophysics in Seafloor Observatories data analysis

    NASA Astrophysics Data System (ADS)

    Embriaco, Davide; De Caro, Mariagrazia; De Santis, Angelo; Etiope, Giuseppe; Frugoni, Francesco; Giovanetti, Gabriele; Lo Bue, Nadia; Marinaro, Giuditta; Monna, Stephen; Montuori, Caterina; Sgroi, Tiziana; Beranzoli, Laura; Favali, Paolo

    2016-04-01

    Continuous time-series in deep ocean waters are the basis for an original approach in ocean exploration. The observation of phenomena variability over time is key to understanding many Earth processes, among which: hydrothermal systems, active tectonics, and ecosystem life cycles. Geo-hazards at sea have often been studied with a single-parameter approach on a short time-scale, but it is now becoming clear that to understand these phenomena and, specifically, to identify precursors to very energetic events, such as mega-earthquakes, tsunamis and volcanic eruptions, continuous long-term multiparameter monitoring is strongly needed. In fact, given a signal of interest, by using several sensors recording simultaneously it is possible to identify the contribution of different sources to this signal, and to be less prone to false associations. In Europe, large cabled systems with marine sensors are being developed for near real-time and real-time long-term monitoring of ocean processes within the EMSO (European Multidisciplinary Seafloor and water column Observatory www.emso-eu.org) Research Infrastructure. Obtaining good quality long-term multiparameter data from sensors on-board seafloor observatories, which are the base of a multidisciplinary approach, is a challenging task. We describe the main steps we have taken to retrieve good quality multiparametric data acquired by GEOSTAR class seafloor observatories, both standalone and cabled, deployed at various sites offshore European coast during the last decade. Starting from this data we show the application of a multidisciplinary approach with some examples coming from experiments in EMSO sites.

  17. Methodology for sensitivity analysis, approximate analysis, and design optimization in CFD for multidisciplinary applications

    NASA Technical Reports Server (NTRS)

    Taylor, Arthur C., III; Hou, Gene W.

    1993-01-01

    In this study involving advanced fluid flow codes, an incremental iterative formulation (also known as the delta or correction form) together with the well-known spatially-split approximate factorization algorithm, is presented for solving the very large sparse systems of linear equations which are associated with aerodynamic sensitivity analysis. For smaller 2D problems, a direct method can be applied to solve these linear equations in either the standard or the incremental form, in which case the two are equivalent. Iterative methods are needed for larger 2D and future 3D applications, however, because direct methods require much more computer memory than is currently available. Iterative methods for solving these equations in the standard form are generally unsatisfactory due to an ill-conditioning of the coefficient matrix; this problem can be overcome when these equations are cast in the incremental form. These and other benefits are discussed. The methodology is successfully implemented and tested in 2D using an upwind, cell-centered, finite volume formulation applied to the thin-layer Navier-Stokes equations. Results are presented for two sample airfoil problems: (1) subsonic low Reynolds number laminar flow; and (2) transonic high Reynolds number turbulent flow.

  18. Methodology for Sensitivity Analysis, Approximate Analysis, and Design Optimization in CFD for Multidisciplinary Applications

    NASA Technical Reports Server (NTRS)

    Taylor, Arthur C., III; Hou, Gene W.

    1996-01-01

    An incremental iterative formulation together with the well-known spatially split approximate-factorization algorithm, is presented for solving the large, sparse systems of linear equations that are associated with aerodynamic sensitivity analysis. This formulation is also known as the 'delta' or 'correction' form. For the smaller two dimensional problems, a direct method can be applied to solve these linear equations in either the standard or the incremental form, in which case the two are equivalent. However, iterative methods are needed for larger two-dimensional and three dimensional applications because direct methods require more computer memory than is currently available. Iterative methods for solving these equations in the standard form are generally unsatisfactory due to an ill-conditioned coefficient matrix; this problem is overcome when these equations are cast in the incremental form. The methodology is successfully implemented and tested using an upwind cell-centered finite-volume formulation applied in two dimensions to the thin-layer Navier-Stokes equations for external flow over an airfoil. In three dimensions this methodology is demonstrated with a marching-solution algorithm for the Euler equations to calculate supersonic flow over the High-Speed Civil Transport configuration (HSCT 24E). The sensitivity derivatives obtained with the incremental iterative method from a marching Euler code are used in a design-improvement study of the HSCT configuration that involves thickness. camber, and planform design variables.

  19. Analysis of human rotavirus strains prevailing in Bangladesh in relation to nationwide floods brought by the 1988 monsoon.

    PubMed

    Ahmed, M U; Urasawa, S; Taniguchi, K; Urasawa, T; Kobayashi, N; Wakasugi, F; Islam, A I; Sahikh, H A

    1991-10-01

    The virologic character of human rotavirus strains prevailing in Bangladesh was investigated in relation to the devastating nationwide floods brought by the 1988 monsoon. Human rotaviruses contained in stool specimens that were collected from inpatients with infantile and adult diarrhea in two hospitals in Mymensingh over a 13-month period (January 1988 to January 1989) and in one hospital in Dhaka over a 3-month period (February to April 1988) were examined for their subgroup, VP7 serotype, and RNA electropherotype. In concurrence with the spread of the flood (from the middle of August 1988), the number of infantile and adult diarrhea patients increased greatly. At the same time, the proportion of rotavirus-positive specimens in all diarrhea cases also increased remarkably, reaching 54 and 45% in September and October, respectively. An electrophoretic analysis of viral RNA revealed 17 distinct patterns of viral RNA (14 long and 3 short electropherotypes) and a considerable number of mixed electropherotypes, suggesting the simultaneous infection of some patients with more than two rotavirus strains. It was noteworthy that electropherotypes of rotavirus strains prevailing in the community changed considerably after the spreading of the flood and that the frequency of virus specimens showing mixed electropherotypes increased significantly during the flood period. These results suggest that sudden environmental change caused by the devastating floods seriously affected the epidemiology of rotavirus infections by increasing the opportunity of transmission of the virus and by reducing the resistance of the host to infection. In both pediatric and adult patient groups, serotypes 1 and 2 were the most frequent ones detected, followed by serotype 4.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Cause Resolving of Typhoon Precipitation Using Principle Component Analysis under Complex Interactive Effect of Terrain, Monsoon and Typhoon Vortex

    NASA Astrophysics Data System (ADS)

    Huang, C. L.; Hsu, N. S.

    2015-12-01

    This study develops a novel methodology to resolve the cause of typhoon-induced precipitation using principle component analysis (PCA) and to develop a long lead-time precipitation prediction model. The discovered spatial and temporal features of rainfall are utilized to develop a state-of-the-art descriptive statistical model which can be used to predict long lead-time precipitation during typhoons. The time series of 12-hour precipitation from different types of invasive moving track of typhoons are respectively precede the signal analytical process to qualify the causes of rainfall and to quantify affected degree of each induced cause. The causes include: (1) interaction between typhoon rain band and terrain; (2) co-movement effect induced by typhoon wind field with monsoon; (3) pressure gradient; (4) wind velocity; (5) temperature environment; (6) characteristic distance between typhoon center and surface target station; (7) distance between grade 7 storm radius and surface target station; and (8) relative humidity. The results obtained from PCA can detect the hidden pattern of the eight causes in space and time and can understand the future trends and changes of precipitation. This study applies the developed methodology in Taiwan Island which is constituted by complex diverse terrain formation and height. Results show that: (1) for the typhoon moving toward the direction of 245° to 330°, Causes (1), (2) and (6) are the primary ones to generate rainfall; and (2) for the direction of 330° to 380°, Causes (1), (4) and (6) are the primary ones. Besides, the developed precipitation prediction model by using PCA with the distributed moving track approach (PCA-DMT) is 32% more accurate by that of PCA without distributed moving track approach, and the former model can effectively achieve long lead-time precipitation prediction with an average predicted error of 13% within average 48 hours of forecasted lead-time.

  1. A Simple Tool for the Design and Analysis of Multiple-Reflector Antennas in a Multi-Disciplinary Environment

    NASA Technical Reports Server (NTRS)

    Katz, Daniel S.; Cwik, Tom; Fu, Chuigang; Imbriale, William A.; Jamnejad, Vahraz; Springer, Paul L.; Borgioli, Andrea

    2000-01-01

    The process of designing and analyzing a multiple-reflector system has traditionally been time-intensive, requiring large amounts of both computational and human time. At many frequencies, a discrete approximation of the radiation integral may be used to model the system. The code which implements this physical optics (PO) algorithm was developed at the Jet Propulsion Laboratory. It analyzes systems of antennas in pairs, and for each pair, the analysis can be computationally time-consuming. Additionally, the antennas must be described using a local coordinate system for each antenna, which makes it difficult to integrate the design into a multi-disciplinary framework in which there is traditionally one global coordinate system, even before considering deforming the antenna as prescribed by external structural and/or thermal factors. Finally, setting up the code to correctly analyze all the antenna pairs in the system can take a fair amount of time, and introduces possible human error. The use of parallel computing to reduce the computational time required for the analysis of a given pair of antennas has been previously discussed. This paper focuses on the other problems mentioned above. It will present a methodology and examples of use of an automated tool that performs the analysis of a complete multiple-reflector system in an integrated multi-disciplinary environment (including CAD modeling, and structural and thermal analysis) at the click of a button. This tool, named MOD Tool (Millimeter-wave Optics Design Tool), has been designed and implemented as a distributed tool, with a client that runs almost identically on Unix, Mac, and Windows platforms, and a server that runs primarily on a Unix workstation and can interact with parallel supercomputers with simple instruction from the user interacting with the client.

  2. Risk-based analysis and decision making in multi-disciplinary environments

    NASA Technical Reports Server (NTRS)

    Feather, Martin S.; Cornford, Steven L.; Moran, Kelly

    2003-01-01

    A risk-based decision-making process conceived of and developed at JPL and NASA, has been used to help plan and guide novel technology applications for use on spacecraft. These applications exemplify key challenges inherent in multi-disciplinary design of novel technologies deployed in mission-critical settings. 1) Cross-disciplinary concerns are numerous (e.g., spacecraft involve navigation, propulsion, telecommunications). These concems are cross-coupled and interact in multiple ways (e.g., electromagnetic interference, heat transfer). 2) Time and budget pressures constrain development, operational resources constrain the resulting system (e.g., mass, volume, power). 3) Spacecraft are critical systems that must operate correctly the first time in only partially understood environments, with no chance for repair. 4) Past experience provides only a partial guide: New mission concepts are enhanced and enabled by new technologies, for which past experience is lacking. The decision-making process rests on quantitative assessments of the relationships between three classes of information - objectives (the things the system is to accomplish and constraints on its operation and development), risks (whose occurrence detracts from objectives), and mitigations (options for reducing the likelihood and or severity of risks). The process successfully guides experts to pool their knowledge, using custom-built software to support information gathering and decision-making.

  3. A Simple Tool for the Design and Analysis of Multiple-reflector Antennas in a Multi-disciplinary Environment

    NASA Technical Reports Server (NTRS)

    Katz, Daniel, S.; Borgioli, Andrea; Cwik, Tom; Fu, Chuigang; Imbriale, William A.; Jamnejad, Vahraz; Springer, Paul L.

    1999-01-01

    The process of designing and analyzing a multiple-reflector system has traditionally been time-intensive, requiring large amounts of both computational and human time. At many frequencies, a discrete approximation of the radiation integral may be used to model the system. The code which implements this physical optics (PO) algorithm was developed at the Jet Propulsion Laboratory. It analyzes systems of antennas in pairs, and for each pair, the analysis can be computationally time-consuming. Additionally, the antennas must be described using a local coordinate system for each antenna, which makes it difficult to integrate the design into a multi-disciplinary framework in which there is traditionally one global coordinate system, even before considering deforming the antenna as prescribed by external structural and/or thermal factors. Finally, setting up the code to correctly analyze all the antenna pairs in the system can take a fair amount of time, and introduces possible human error.

  4. Unstructured Finite Volume Computational Thermo-Fluid Dynamic Method for Multi-Disciplinary Analysis and Design Optimization

    NASA Technical Reports Server (NTRS)

    Majumdar, Alok; Schallhorn, Paul

    1998-01-01

    This paper describes a finite volume computational thermo-fluid dynamics method to solve for Navier-Stokes equations in conjunction with energy equation and thermodynamic equation of state in an unstructured coordinate system. The system of equations have been solved by a simultaneous Newton-Raphson method and compared with several benchmark solutions. Excellent agreements have been obtained in each case and the method has been found to be significantly faster than conventional Computational Fluid Dynamic(CFD) methods and therefore has the potential for implementation in Multi-Disciplinary analysis and design optimization in fluid and thermal systems. The paper also describes an algorithm of design optimization based on Newton-Raphson method which has been recently tested in a turbomachinery application.

  5. Long range transport of acidic species over East Asia and the western Pacific Ocean in winter monsoon - a numerical analysis

    SciTech Connect

    Kitada, Toshihiro; Nishizawa, Masato; Isogawa, Seiji; Kondo, Yutaka

    1996-12-31

    In winter season, wind system in East Asia is generally dominated by monsoon. The monsoon is caused by persistent high pressure over Siberia and low pressure over Sea of Okhotsk and Bering Sea, the high pressure which is formed by radiative cooling of air mass over the continent. In Japan area, the monsoon appears as westerly or northwesterly, and usually brings heavy snow over the Japan Sea side of Japanese islands. Since the air mass associated with the monsoon passes over strong emission sources of the East Asia continent, it carries much air pollutants. Significant part of the pollutants should fall to the surface with snow over Japanese islands, and the rest of the pollutants would be distributed into troposphere over the western Pacific Ocean. In this study, to estimate mass budget of air pollutants released over countries in East Asia we have performed 3-D transport/chemistry/deposition simulations for the area of East Asia and the western Pacific Ocean for one month of March, 1994, when an extensive field observation campaign called TEM-WEST Phase B (Pacific Exploratory Mission-West){close_quotes} was conducted. The simulation model includes most of the important chemical species such as NO{sub x}, HNO{sub 3}, SO{sub 2}, sulfate, hydrocarbons, O{sub 3}, H{sub 2}O{sub 2}, etc., and covers 3-D region from 80 to 180 degrees east in longitude, 10 degrees south to 60 degrees north in latitude, and earth`s surface to 10 hPa in vertical. The simulation results will be discussed in connection with the PEM-WEST(B) observation.

  6. Monsoonal alternation of a mixed and a layered structure in the phytoplankton of the euphotic zone of the banda sea (Indonesia): a mathematical analysis of algal pigment fingerprints

    NASA Astrophysics Data System (ADS)

    Gieskes, W. W. C.; Kraay, G. W.; Nontji, A.; Setiapermana, D.; Sutomo

    The chlorophyll a concentration of the upper 25 m of the euphotic zone of the Banda Sea was 5 times higher in August 1984, in the upwelling season during the southeast monsoon, than in February 1985, during the northwest monsoon when a deep chlorophyll maximum layer was presented at 40-80 m. Similarity between stations was calculated by means of a cluster analysis of the concentrations of 4 different chlorophylls and 6 carotenoids. High similarity over large areas, one to the west and one to the east of the Banda Arc, is evidence of the importance of large-scale phenomena influencing the phytoplankton during the monsoons. All samples taken in the deep chlorophyll maximum layer during the northwest monsoon were clustered as a separate group. Multiple regression analysis of chlorophyll a and the four most important accessory pigments suggests that in August 1984 (upwelling season) the fucoxanthin-containing group (mainly diatoms) contributed 50% to the chlorophyll a in the euphotic zone; green algae and Prymnesiophyceae contributed each 20%, Cyanobacteria only 9%. In February 1985, during the downwelling season, pico- and nanoplankton containing 19'-hexanoyloxyfucoxanthin (Prymnesiophyceae) and zeaxanthin (Cyanobacteria) each contributed 40% of total chlorophyll a, both near the surface and in the deep chlorophyll maximum layer; 19'-butanoyloxyfucoxanthin (a marker of certain Prymnesiophyceae and Chrysophyceae) was only present at depth. On the assumption that Chl. b is a pigment confined to green algae, this group contributed 14% of the Chl. a in the deep maximum. Other green-algal pigments were, however, scarce at depth (lutein, violaxanthin), which suggests presence of Prochlorophyta. Shifts in pigment ratios (zeaxanthin : Chl. a; Chl. b : Chl. a), probably related to light adaptation, hinder the use of algal pigment fingerprints for estimating quantitative composition of natural phytoplankton; indeed, differences between samples in pigment signature can have both

  7. Pacific freshening drives Pliocene cooling and Asian monsoon intensification.

    PubMed

    Nie, Junsheng; Stevens, Thomas; Song, Yougui; King, John W; Zhang, Rui; Ji, Shunchuan; Gong, Lisha; Cares, Danielle

    2014-06-27

    The monsoon is a fundamental component of Earth's climate. The Pliocene warm period is characterized by long-term global cooling yet concurrent monsoon dynamics are poorly known. Here we present the first fully quantified and calibrated reconstructions of separate Pliocene air temperature and East Asian summer monsoon precipitation histories on the Chinese Loess Plateau through joint analysis of loess/red clay magnetic parameters with different sensitivities to air temperature and precipitation. East Asian summer monsoon precipitation shows an intensified trend, paradoxically at the same time that climate cooled. We propose a hitherto unrecognized feedback where persistently intensified East Asian summer monsoon during the late Pliocene, triggered by the gradual closure of the Panama Seaway, reinforced late Pliocene Pacific freshening, sea-ice development and ice volume increase, culminating in initiation of the extensive Northern Hemisphere glaciations of the Quaternary Ice Age. This feedback mechanism represents a fundamental reinterpretation of the origin of the Quaternary glaciations and the impact of the monsoon.

  8. Multidisciplinary team care for people with rheumatoid arthritis: a systematic review and meta-analysis.

    PubMed

    Bearne, Lindsay M; Byrne, Anne-Marie; Segrave, Hannah; White, Claire M

    2016-03-01

    The objective of this study was to systematically review the evidence from randomised controlled trials (RCTs) evaluating the effectiveness of multidisciplinary team (MDT) care for the management of disability, disease activity and quality of life (QoL) in adults with rheumatoid arthritis (RA). Data sources identified published (MEDLINE, PsychINFO, EMBASE, CINAHL, Web of Science, CENTRAL) and unpublished (OpenGrey) literature. Independent data extraction and quality assessment, using the Cochrane risk of bias tool, were conducted by two reviewers. The primary outcome was change in disability at 12 months; secondary outcomes included disability at other time points and disease activity and QoL at 12 months. Where possible, the pooled effect sizes were calculated for inpatient or outpatient MDT interventions. Four hundred and fifteen studies were retrieved. Twelve manuscripts, which reported 10 RCTs, representing 1147 participants were included. Only data from five high- or moderate-quality trials were pooled according to clinical setting. There was no difference in disability between inpatient MDT care and any comparison group [mean difference (95% confidence intervals) 0.04, -0.13 to 0.20] or between outpatient MDT care and comparison groups (0.09, -0.07 to 0.25) at 12 months. There was no difference in disability at 2 years or <12 months or disease activity and QoL at 12 months between MDT care and any comparison group. There is limited evidence evaluating the effect of MDT care on disability, disease activity or QoL in people with RA. There is likely to be no effect of MDT care on disability at 12 months or other time points.

  9. A solar variability driven monsoon see-saw: switching relationships of the Holocene East Asian-Australian summer monsoons

    NASA Astrophysics Data System (ADS)

    Eroglu, Deniz; Ozken, Ibrahim; McRobie, Fiona; Stemler, Thomas; Marwan, Norbert; Wyrwoll, Karl-Heinz; Kurths, Juergen

    2016-04-01

    The East Asian-Indonesian-Australian monsoon is the predominant low latitude monsoon system, providing a major global scale heat source. Here we apply newly developed non-linear time series techniques on speleothem climate proxies, from eastern China and northwestern Australia and establish relationships between the two summer monsoon regimes over the last ˜9000 years. We identify significant variations in monsoonal activity, both dry and wet phases, at millennial to multi-centennial time scales and demonstrate for the first time the existence of a see-saw antiphase relationship between the two regional monsoon systems. Our analysis attributes this inter-hemispheric linkage to the solar variability that is effecting both monsoon systems.

  10. Energetics and monsoon bifurcations

    NASA Astrophysics Data System (ADS)

    Seshadri, Ashwin K.

    2017-01-01

    Monsoons involve increases in dry static energy (DSE), with primary contributions from increased shortwave radiation and condensation of water vapor, compensated by DSE export via horizontal fluxes in monsoonal circulations. We introduce a simple box-model characterizing evolution of the DSE budget to study nonlinear dynamics of steady-state monsoons. Horizontal fluxes of DSE are stabilizing during monsoons, exporting DSE and hence weakening the monsoonal circulation. By contrast latent heat addition (LHA) due to condensation of water vapor destabilizes, by increasing the DSE budget. These two factors, horizontal DSE fluxes and LHA, are most strongly dependent on the contrast in tropospheric mean temperature between land and ocean. For the steady-state DSE in the box-model to be stable, the DSE flux should depend more strongly on the temperature contrast than LHA; stronger circulation then reduces DSE and thereby restores equilibrium. We present conditions for this to occur. The main focus of the paper is describing conditions for bifurcation behavior of simple models. Previous authors presented a minimal model of abrupt monsoon transitions and argued that such behavior can be related to a positive feedback called the `moisture advection feedback'. However, by accounting for the effect of vertical lapse rate of temperature on the DSE flux, we show that bifurcations are not a generic property of such models despite these fluxes being nonlinear in the temperature contrast. We explain the origin of this behavior and describe conditions for a bifurcation to occur. This is illustrated for the case of the July-mean monsoon over India. The default model with mean parameter estimates does not contain a bifurcation, but the model admits bifurcation as parameters are varied.

  11. Effectiveness of multidisciplinary team case management: difference-in-differences analysis

    PubMed Central

    Kristensen, Søren Rud; Checkland, Kath; Bower, Peter

    2016-01-01

    Objectives To evaluate a multidisciplinary team (MDT) case management intervention, at the individual (direct effects of intervention) and practice levels (potential spillover effects). Design Difference-in-differences design with multiple intervention start dates, analysing hospital admissions data. In secondary analyses, we stratified individual-level results by risk score. Setting Single clinical commissioning group (CCG) in the UK's National Health Service (NHS). Participants At the individual level, we matched 2049 intervention patients using propensity scoring one-to-one with control patients. At the practice level, 30 practices were compared using a natural experiment through staged implementation. Intervention Practice Integrated Care Teams (PICTs), using MDT case management of high-risk patients together with a summary record of care versus usual care. Direct and indirect outcome measures Primary measures of intervention effects were accident and emergency (A&E) visits; inpatient non-elective stays, 30-day re-admissions; inpatient elective stays; outpatient visits; and admissions for ambulatory care sensitive conditions. Secondary measures included inpatient length of stay; total cost of secondary care services; and patient satisfaction (at the practice level only). Results At the individual level, we found slight, clinically trivial increases in inpatient non-elective admissions (+0.01 admissions per patient per month; 95% CI 0.00 to 0.01. Effect size (ES): 0.02) and 30-day re-admissions (+0.00; 0.00 to 0.01. ES: 0.03). We found no indication that highest risk patients benefitted more from the intervention. At the practice level, we found a small decrease in inpatient non-elective admissions (−0.63 admissions per 1000 patients per month; −1.17 to −0.09. ES: −0.24). However, this result did not withstand a robustness check; the estimate may have absorbed some differences in underlying practice trends. Conclusions The intervention does not meet its

  12. Sensitivity analysis and multidisciplinary optimization for aircraft design - Recent advances and results

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1988-01-01

    Optimization by decomposition, complex system sensitivity analysis, and a rapid growth of disciplinary sensitivity analysis are some of the recent developments that hold promise of a quantum jump in the support engineers receive from computers in the quantitative aspects of design. Review of the salient points of these techniques is given and illustrated by examples from aircraft design as a process that combines the best of human intellect and computer power to manipulate data.

  13. Sensitivity analysis and multidisciplinary optimization for aircraft design: Recent advances and results

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1988-01-01

    Optimization by decomposition, complex system sensitivity analysis, and a rapid growth of disciplinary sensitivity analysis are some of the recent developments that hold promise of a quantum jump in the support engineers receive from computers in the quantitative aspects of design. Review of the salient points of these techniques is given and illustrated by examples from aircraft design as a process that combines the best of human intellect and computer power to manipulate data.

  14. Non-stationary analysis of dry spells in monsoon season of Senegal River Basin using data from Regional Climate Models (RCMs)

    NASA Astrophysics Data System (ADS)

    Giraldo Osorio, J. D.; García Galiano, S. G.

    2012-07-01

    SummaryThe Senegal River Basin, located in West Africa, has been affected by several droughts since the end of the 1960s. In its valley, which is densely populated and highly vulnerable to climate variability and water availability, agricultural activities provide the livelihood for thousands of people. Increasing the knowledge about plausible trends of drought events will allow to improve the adaptation and mitigation measures in order to build "adaptive capacity" to climate change in West Africa. An innovative methodology for the non-stationary analysis of droughts events, which allows the prediction of regional trends associated to several return periods, is presented. The analyses were based on Regional Climate Models (RCMs) provided by the European ENSEMBLES project for West Africa, together with observed data. A non-stationary behaviour of the annual series of maximum length of dry spells (AMDSL) in the monsoon season is reflected in temporal changes in mean and variance. The non-stationary nature of hydrometeorological series, due to climate change and anthropogenic activities, is the main criticism to traditional frequency analysis. Therefore, in this paper, the modelling tool GAMLSS (Generalized Additive Models for Location, Scale and Shape), is applied to develop regional probability density functions (pdfs) fitted to AMDSL series for the monsoon season in the Senegal River Basin. The skills of RCMs in the representation of maximum length of dry spells observed for the period 1970-1990, are evaluated considering observed data. Based on the results obtained, a first selection of the RCMs with which to apply GAMLSS to the AMDSL series identified, for the time period 1970-2050, is made. The results of GAMLSS analysis exhibit divergent trends, with different value ranges for parameters of probability distributions being detected. Therefore, in the second stage of the paper, regional pdfs are constructed using bootstrapping distributions based on probabilistic

  15. Past dynamics of the Australian monsoon: precession, phase and links to the global monsoon

    NASA Astrophysics Data System (ADS)

    Beaufort, L.; van der Kaars, S.; Bassinot, F. C.; Moron, V.

    2010-06-01

    Past variations in the dynamics of the Australian monsoon have been estimated from multi-proxy analysis of a core retrieved in the Eastern Banda Sea. Records of coccolith and pollen assemblages, spanning the last 150,000 years, allow reconstruction of past primary production in the Banda Sea, summer moisture availability, and the length of the dry season in Northern Australia and Southeastern Indonesia. The amount of moisture available during the summer monsoon follows typical glacial/interglacial dynamics with a broad asymmetrical 100-kyr cycle. Primary production and length of the dry season appear to be closely related, given that they follow the precessional cycle with the same phase (August insolation). This indicates their independence from ice-volume variations. The present inter-annual variability of both parameters is related to El Niño Southern Oscillation (ENSO), which modulates the Australian Winter Monsoon (AWM). The precessional pattern observed in the past dynamics of the AWM is found in ENSO and monsoon records of other regions. A marked shift in the monsoon intensity occurring during the mid Holocene during a period of constant ice volume, suggest that low latitude climatic variation precedes global ice volume. This precessional pattern suggests that a common forcing mechanism underlies low latitude climate dynamics, acting specifically and synchronically on the different monsoon systems.

  16. Past dynamics of the Australian monsoon: precession, phase and links to the global monsoon concept

    NASA Astrophysics Data System (ADS)

    Beaufort, L.; van der Kaars, S.; Bassinot, F. C.; Moron, V.

    2010-10-01

    Past variations in the dynamics of the Australian monsoon have been estimated from multi-proxy analysis of a core retrieved in the Eastern Banda Sea. Records of coccolith and pollen assemblages, spanning the last 150 000 years, allow reconstruction of past primary production in the Banda Sea, summer moisture availability, and the length of the dry season in northern Australia and southeastern Indonesia. The amount of moisture available during the summer monsoon follows typical glacial/interglacial dynamics with a broad asymmetrical 100-kyr cycle. Primary production and length of the dry season appear to be closely related, given that they follow the precessional cycle with the same phase. This indicates their independence from ice-volume variations. The present inter-annual variability of both parameters is related to El Niño Southern Oscillation (ENSO), which modulates the Australian Winter Monsoon (AWM). The precessional pattern observed in the past dynamics of the AWM is found in ENSO and monsoon records of other regions. A marked shift in the monsoon intensity occurring during the mid Holocene during a period of constant ice volume, suggests that low latitude climatic variation precedes increases in global ice volume. This precessional pattern suggests that a common forcing mechanism underlies low latitude climate dynamics, acting specifically and synchronously on the different monsoon systems.

  17. Assessment of the 1997-1998 Asian Monsoon Anomalies

    NASA Technical Reports Server (NTRS)

    Lau, William K.-M.; Wu, H.-T.

    1999-01-01

    Using State-of-the-art satellite-gauge monthly rainfall estimate and optimally interpolated sea surface temperature (SST) data, we have assessed the 1997-98 Asian monsoon anomalies in terms of three basic causal factors: basin-scale SST, regional coupling, and internal variability. Singular Value Decomposition analysis of rainfall and SST are carried out globally over the entire tropics and regionally over the Asian monsoon domain. Contributions to monsoon rainfall predictability by various factors are evaluated from cumulative anomaly correlation with dominant regional SVD modes. Results reveal a dominant, large-scale monsoon-El Nino coupled mode with well-defined centers of action in the near-equatorial monsoon regions. it is noted that some subcontinental regions such as all-India, or arbitrarily chosen land regions over East Asia, while important socio-economically, are not near the centers of influence from El Nino, hence are not necessarily representative of the response of the entire monsoon region to El Nino. The observed 1997-98 Asian monsoon anomalies are found to be very complex with approximately 34% of the anomalies attributable to basin- scale SST influence associated with El Nino. Regional coupled processes contribute an additional 19%, leaving about 47% due to internal dynamics. Also noted is that the highest monsoon predictability is not necessary associated with major El Nino events (e.g. 1997, 1982) but rather in non-El Nino years (e.g. 1980, 1988) when contributions from the regional coupled modes far exceed those from the basin-scale SST. The results suggest that in order to improve monsoon seasonal-to-interannual predictability, there is a need to exploit not only monsoon-El Nino relationship, but also monsoon regional coupled processes and their modulation by long-term climate change.

  18. Evaluation of soil moisture data products over Indian region and analysis of spatio-temporal characteristics with respect to monsoon rainfall

    NASA Astrophysics Data System (ADS)

    Sathyanadh, Anusha; Karipot, Anandakumar; Ranalkar, Manish; Prabhakaran, Thara

    2016-11-01

    Soil moisture (SM) is an essential climate variable of greater relevance in the monsoon scenario, hence validation and understanding of its spatio-temporal variability over the Indian region is of high significance. In the present study, five SM products are evaluated against in situ SM measurements conducted by India Meteorological Department and the selected data product is used for spatio-temporal characterization of SM in relation to monsoon rainfall. The data products evaluated are: European Space Agency's merged satellite SM, Modern-Era Retrospective analysis for Research and Applications (MERRA) Land SM, ECMWF's ERA interim SM, Climate Forecast System Reanalysis SM, and Global Land Data Assimilation System Noah Land Surface Model SM. Comparisons show that seasonal SM patterns in all products generally follow the characteristics of rainfall, even though there are certain differences in details. The statistical estimates indicate fairly good agreement between in situ and the five products, with some variations among them and over the homogeneous rainfall regions. On comparison, MERRA SM is found appropriate for further analyses on spatio-temporal characteristics, which are then carried out with the 20 year (1993-2012) SM data. Stability analyses revealed SM patterns indicative of relative SM variability as well as persistence. The spatial stability analysis depicts dry and wet patterns and their seasonal variations over different geographical locations in relation to all India spatial average. Large temporal variations are found over central, western and northern Indian regions caused by large intraseasonal variability in rainfall. In brief, intraseasonal and interannual soil moisture variations broadly follow the rainfall pattern, with long-term influences attributed to SM memory effects. The soil moisture persistence and dominant scales of variability are explored with autocorrelation and wavelet transform techniques. Seasonal persistence is large over

  19. Integration of Multifidelity Multidisciplinary Computer Codes for Design and Analysis of Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Geiselhart, Karl A.; Ozoroski, Lori P.; Fenbert, James W.; Shields, Elwood W.; Li, Wu

    2011-01-01

    This paper documents the development of a conceptual level integrated process for design and analysis of efficient and environmentally acceptable supersonic aircraft. To overcome the technical challenges to achieve this goal, a conceptual design capability which provides users with the ability to examine the integrated solution between all disciplines and facilitates the application of multidiscipline design, analysis, and optimization on a scale greater than previously achieved, is needed. The described capability is both an interactive design environment as well as a high powered optimization system with a unique blend of low, mixed and high-fidelity engineering tools combined together in the software integration framework, ModelCenter. The various modules are described and capabilities of the system are demonstrated. The current limitations and proposed future enhancements are also discussed.

  20. Parametric Sensitivity Analysis for the Asian Summer Monsoon Precipitation Simulation in the Beijing Climate Center AGCM Version 2.1

    SciTech Connect

    Yang, Ben; Zhang, Yaocun; Qian, Yun; Wu, Tongwen; Huang, Anning; Fang, Yongjie

    2015-07-15

    In this study, we apply an efficient sampling approach and conduct a large number of simulations to explore the sensitivity of the simulated Asian summer monsoon (ASM) precipitation, including the climatological state and interannual variability, to eight parameters related to the cloud and precipitation processes in the Beijing Climate Center AGCM version 2.1 (BCC_AGCM2.1). Our results show that BCC_AGCM2.1 has large biases in simulating the ASM precipitation. The precipitation efficiency and evaporation coefficient for deep convection are the most sensitive parameters in simulating the ASM precipitation. With optimal parameter values, the simulated precipitation climatology could be remarkably improved, e.g. increased precipitation over the equator Indian Ocean, suppressed precipitation over the Philippine Sea, and more realistic Meiyu distribution over Eastern China. The ASM precipitation interannual variability is further analyzed, with a focus on the ENSO impacts. It shows the simulations with better ASM precipitation climatology can also produce more realistic precipitation anomalies during El Niño decaying summer. In the low-skill experiments for precipitation climatology, the ENSO-induced precipitation anomalies are most significant over continents (vs. over ocean in observation) in the South Asian monsoon region. More realistic results are derived from the higher-skill experiments with stronger anomalies over the Indian Ocean and weaker anomalies over India and the western Pacific, favoring more evident easterly anomalies forced by the tropical Indian Ocean warming and stronger Indian Ocean-western Pacific tele-connection as observed. Our model results reveal a strong connection between the simulated ASM precipitation climatological state and interannual variability in BCC_AGCM2.1 when key parameters are perturbed.

  1. Program design by a multidisciplinary team. [for structural finite element analysis on STAR-100 computer

    NASA Technical Reports Server (NTRS)

    Voigt, S.

    1975-01-01

    The use of software engineering aids in the design of a structural finite-element analysis computer program for the STAR-100 computer is described. Nested functional diagrams to aid in communication among design team members were used, and a standardized specification format to describe modules designed by various members was adopted. This is a report of current work in which use of the functional diagrams provided continuity and helped resolve some of the problems arising in this long-running part-time project.

  2. Functional status, physical activity level, and exercise regularity in patients with fibromyalgia after Multidisciplinary treatment: retrospective analysis of a randomized controlled trial.

    PubMed

    Salvat, I; Zaldivar, P; Monterde, S; Montull, S; Miralles, I; Castel, A

    2017-03-01

    Multidisciplinary treatments have shown to be effective for fibromyalgia. We report detailed functional outcomes of patients with fibromyalgia who attended a 3-month Multidisciplinary treatment program. The hypothesis was that patients would have increased functional status, physical activity level, and exercise regularity after attending this program. We performed a retrospective analysis of a randomized, simple blinded clinical trial. The inclusion criteria consisted of female sex, a diagnosis of fibromyalgia, age 18-60  and 3-8 years of schooling. Measures from the Fibromyalgia Impact Questionnaire (FIQ) and the COOP/WONCA Functional Health Assessment Charts (WONCA) were obtained before and at the end of the treatment and at 3-, 6-, and 12-month follow-ups. Patients recorded their number of steps per day with pedometers. They performed the six-minute walk test (6 MW) before and after treatment. In total, 155 women participated in the study. Their median (interquartile interval) FIQ score was 68.0 (53.0-77.0) at the beginning of the treatment, and the difference between the Multidisciplinary and Control groups was statistically and clinically significant in all of the measures (except the 6-month follow-up). The WONCA charts showed significant clinical improvements in the Multidisciplinary group, with physical fitness in the normal range across almost all values. In that group, steps/day showed more regularity, and the 6 MW results showed improvement of -33.00 (-59.8 to -8.25) m, and the differences from the Control group were statistically significant. The patients who underwent the Multidisciplinary treatment had improved functional status, physical activity level, and exercise regularity. The functional improvements were maintained 1 year after treatment completion.

  3. Toward multidisciplinary use of LANDSAT: Interfacing computerized LANDSAT analysis systems with geographic information systems

    NASA Technical Reports Server (NTRS)

    Myers, W. L.

    1981-01-01

    The LANDSAT-geographic information system (GIS) interface must summarize the results of the LANDSAT classification over the same cells that serve as geographic referencing units for the GIS, and output these summaries on a cell-by-cell basis in a form that is readable by the input routines of the GIS. The ZONAL interface for cell-oriented systems consists of two primary programs. The PIXCEL program scans the grid of cells and outputs a channel of pixels. Each pixel contains not the reflectance values but the identifier of the cell in which the center of the pixel is located. This file of pixelized cells along with the results of a pixel-by-pixel classification of the scene produced by the LANDSAT analysis system are input to the CELSUM program which then outputs a cell-by-cell summary formatted according to the requirements of the host GIS. Cross-correlation of the LANDSAT layer with the other layers in the data base is accomplished with the analysis and display facilities of the GIS.

  4. Multi-Disciplinary Analysis for Future Launch Systems Using NASA's Advanced Engineering Environment (AEE)

    NASA Technical Reports Server (NTRS)

    Monell, Donald; Mathias, Donovan; Reuther, James; Garn, Michelle

    2003-01-01

    A new engineering environment constructed for the purposes of analyzing and designing Reusable Launch Vehicles (RLVs) is presented. The new environment has been developed to allow NASA to perform independent analysis and design of emerging RLV architectures and technologies. The new Advanced Engineering Environment (AEE) is both collaborative and distributed. It facilitates integration of the analyses by both vehicle performance disciplines and life-cycle disciplines. Current performance disciplines supported include: weights and sizing, aerodynamics, trajectories, propulsion, structural loads, and CAD-based geometries. Current life-cycle disciplines supported include: DDT&E cost, production costs, operations costs, flight rates, safety and reliability, and system economics. Involving six NASA centers (ARC, LaRC, MSFC, KSC, GRC and JSC), AEE has been tailored to serve as a web-accessed agency-wide source for all of NASA's future launch vehicle systems engineering functions. Thus, it is configured to facilitate (a) data management, (b) automated tool/process integration and execution, and (c) data visualization and presentation. The core components of the integrated framework are a customized PTC Windchill product data management server, a set of RLV analysis and design tools integrated using Phoenix Integration's Model Center, and an XML-based data capture and transfer protocol. The AEE system has seen production use during the Initial Architecture and Technology Review for the NASA 2nd Generation RLV program, and it continues to undergo development and enhancements in support of its current main customer, the NASA Next Generation Launch Technology (NGLT) program.

  5. Hudson Canyon benthic habitats characterization and mapping by integrated analysis of multidisciplinary data

    NASA Astrophysics Data System (ADS)

    Pierdomenico, Martina; Guida, Vincent G.; Rona, Peter A.; Macelloni, Leonardo; Scranton, Mary I.; Asper, Vernon; Diercks, Arne

    2013-04-01

    Hudson Canyon, about 180 km SE of New York City, is the largest eastern U.S. submarine canyon and is under consideration for HAPC (Habitat Area of Particular Concern) status, representing a fisheries and biodiversity hot spot. Interest in the area, within the perspective of ecosystem based management, marine spatial planning, habitat and species conservation, led to a joint project between NOAA Northeast Fisheries, U.S. Geological Survey (USGS), Mississippi Mineral Research Institute (MMRI), National Institute for Undersea Science and Technology (NIUST), Stony Brook and Rutgers Universities for the study of benthic habitats, that includes the assembly of existing data with newly collected ones: acoustic mapping, visual ground-truthing, hydrographic, sedimentological, and trawl data collections. Acoustic mapping, performed using AUV-mounted multibeam sonar, provided ultra-high resolution bathymetric and backscatter imagery (3m and 1m respectively) at all water depths for identification of geomorphological features and for the characterization of surficial sediments along the two thirds of the shelf portion of the canyon. Identification of benthic and demersal communities was accomplished by visual ground thruthing with underwater vehicle video and still cameras, and from trawl catch data. A CTD-rosette sampler provided water column salinity-temperature profiles and water samples for dissolved methane analysis in the vicinity of suspected bottom sources. Analysis of data revealed a complex of topographic structures and hydrological patterns that provide a wide range of physical habitats in a relatively small area. A mosaic of sandy and muddy substrates, gravel beds, rock outcrops, and semilithified clay outcrops host rich and varied faunal assemblages, including deepwater corals and sponge communities. Pockmark fields, occurring below 300 m depth, suggest that methane-based chemosynthetic carbonate deposition contributes to creation of specific hard bottom habitats

  6. DataView: a computational visualisation system for multidisciplinary design and analysis

    NASA Astrophysics Data System (ADS)

    Wang, Chengen

    2016-01-01

    Rapidly processing raw data and effectively extracting underlining information from huge volumes of multivariate data become essential to all decision-making processes in sectors like finance, government, medical care, climate analysis, industries, science, etc. Remarkably, visualisation is recognised as a fundamental technology that props up human comprehension, cognition and utilisation of burgeoning amounts of heterogeneous data. This paper presents a computational visualisation system, named DataView, which has been developed for graphically displaying and capturing outcomes of multiphysics problem-solvers widely used in engineering fields. The DataView is functionally composed of techniques for table/diagram representation, and graphical illustration of scalar, vector and tensor fields. The field visualisation techniques are implemented on the basis of a range of linear and non-linear meshes, which flexibly adapts to disparate data representation schemas adopted by a variety of disciplinary problem-solvers. The visualisation system has been successfully applied to a number of engineering problems, of which some illustrations are presented to demonstrate effectiveness of the visualisation techniques.

  7. On the Origin of Monsoon

    NASA Technical Reports Server (NTRS)

    Chao, Winston C.; Chen, Baode; Einaudi, Franco (Technical Monitor)

    2000-01-01

    It is a long-held fundamental belief that the basic cause of a monsoon is land-sea thermal contrast on the continental scale. Through general circulation model experiments we demonstrate that this belief should be changed. The Asian and Australian summer monsoon circulations are largely intact in an experiment in which Asia, maritime continent, and Australia are replaced by ocean. It is also shown that the change resulting from such replacement is in general due more to the removal of topography than to the removal of land-sea contrast. Therefore, land-sea contrast plays only a minor modifying role in Asian and Australian summer monsoons. This also happens to the Central American summer monsoon. However, the same thing cannot be said of the African and South American summer monsoons. In Asian and Australian winter monsoons land-sea contrast also plays only a minor role. Our interpretation for the origin of monsoon is that the summer monsoon is the result of ITCZ's (intertropical convergence zones) peak being substantially (more than 10 degrees) away from the equator. The origin of the ITCZ has been previously interpreted by Chao. The circulation around thus located ITCZ, previously interpreted by Chao and Chen through the modified Gill solution and briefly described in this paper, explains the monsoon circulation. The longitudinal location of the ITCZs is determined by the distribution of surface conditions. ITCZ's favor locations of higher SST as in western Pacific and Indian Ocean, or tropical landmass, due to land-sea contrast, as in tropical Africa and South America. Thus, the role of landmass in the origin of monsoon can be replaced by ocean of sufficiently high SST. Furthermore, the ITCZ circulation extends into the tropics in the other hemisphere to give rise to the winter monsoon circulation there. Also through the equivalence of land-sea contrast and higher SST, it is argued that the basic monsoon onset mechanism proposed by Chao is valid for all monsoons.

  8. Monsoon '90 - Preliminary SAR results

    NASA Technical Reports Server (NTRS)

    Dubois, Pascale C.; Van Zyl, Jakob J.; Guerra, Abel G.

    1992-01-01

    Multifrequency polarimetric synthetic aperture radar (SAR) images of the Walnut Gulch watershed near Tombstone, Arizona were acquired on 28 Mar. 1990 and on 1 Aug. 1990. Trihedral corner reflectors were deployed prior to both overflights to allow calibration of the two SAR data sets. During both overflights, gravimetric soil moisture and dielectric constant measurements were made. Detailed vegetation height, density, and water content measurements were made as part of the Monsoon 1990 Experiment. Preliminary results based on analysis of the multitemporal polarimetric SAR data are presented. Only the C-band data (5.7-cm wavelength) radar images show significant difference between Mar. and Aug., with the strongest difference observed in the HV images. Based on the radar data analysis and the in situ measurements, we conclude that these differences are mainly due to changes in the vegetation and not due to the soil moisture changes.

  9. Monsoon 1990: Preliminary SAR results

    NASA Technical Reports Server (NTRS)

    Vanzyl, Jakob J.; Dubois, Pascale; Guerra, Abel

    1991-01-01

    Multifrequency polarimetric synthetic aperture radar (SAR) images of the Walnut Gulch watershed near Tombstone, Arizona were acquired on 28 Mar. 1990 and on 1 Aug. 1990. Trihedral corner reflectors were deployed prior to both overflights to allow calibration of the two SAR data sets. During both overflights, gravimetric soil moisture and dielectric constant measurements were made. Detailed vegetation height, density, and water content measurements were made as part of the Monsoon 1990 Experiment. Preliminary results based on analysis of the multitemporal polarimetric SAR data are presented. Only the C-band data (5.7-cm wavelength) radar images show significant difference between Mar. and Aug., with the strongest difference observed in the HV images. Based on the radar data analysis and the in situ measurements, we conclude that these differences are mainly due to changes in the vegetation and not due to the soil moisture changes.

  10. Is precipitation a predictor of mortality in Bangladesh? A multi-stratified analysis in a South Asian monsoon climate.

    PubMed

    Burkart, Katrin; Kinney, Patrick

    2016-05-15

    While numerous studies have assessed the association between temperature and mortality in various locations, few have addressed the relationship between precipitation and mortality. Given the high amounts of rainfall in many tropical monsoon areas and the often seasonally pronounced differences, there might be a potentially strong impact on health outcomes and death. In this study, we investigated the association between precipitation and daily death counts in Bangladesh from 2003 to 2007 using regression models with a quasipoisson distribution adjusting for long-term time and seasonal trends, day of the month, age and perceived temperature. Effects were assessed for all ages, the elderly and by gender. During the dry season a sharp increase in death risk was found at very high precipitation amounts which are most likely to be cyclone-related. This cyclone effect was most pronounced for females at the immediate day with an increase of 18.7% (3.8-35.6%) in non-external cause mortality per mm precipitation above 5mm. At longer lags we found a negative association between precipitation and mortality indicating some kind of dry effect which was more pronounced for the elderly with a mortality increase of 4.4% (2.6-6.2%) per mm decrease in precipitation. During the rainy season, we observed a protective effect of rainfall which was strongest during periods of seasonally high equivalent temperatures with a decrease in mortality of 4.0% (2.3-5.6%) per mm increase in precipitation on the immediate day. The observed associations between precipitation and mortality differed by season, age and gender. Generally, a strong short-term increase in mortality was associated with cyclonic activity during the dry season, while ongoing low rainfall seemed to have an adverse impact at higher lags. During the rainy season, precipitation seemed to mitigate heat effects.

  11. Current multidisciplinary oncology series

    PubMed Central

    Sebio, Ana

    2014-01-01

    “Cancers of the Colon and Rectum: A Multidisciplinary Approach to Diagnosis and Management” represents a truly multidisciplinary compendium of the management of these tumors that will be of value both for any physician involved in providing care for colorectal cancer (CRC) patients as well as for trainees of many medical disciplines.

  12. Leaf physiognomy and climate: Are monsoon systems different?

    NASA Astrophysics Data System (ADS)

    Jacques, Frédéric M. B.; Su, Tao; Spicer, Robert A.; Xing, Yaowu; Huang, Yongjiang; Wang, Weiming; Zhou, Zhekun

    2011-03-01

    Our understanding of past climatic changes depends on our ability to obtain reliable palaeoclimate reconstructions. Climate Leaf Analysis Multivariate Program (CLAMP) uses the physiognomy of woody dicot leaf assemblages to quantitatively reconstruct terrestrial palaeoclimates. However, the present calibrations do not always allow us to reconstruct correctly the climate of some regions due to differing palaeofloristic histories. Present calibrations are also inappropriate for regions experiencing strong monsoon regimes. To help solve this problem, we have established a new calibration that can accommodate monsoonal climates in Asia. Our new calibration is based on the Physg3brcAZ dataset with 45 new Chinese sites added. These Chinese sites are taken from humid to mesic vegetations across China, and all are influenced by monsoonal conditions to some extent. They plot in a distinct part of physiognomic space, whether they are analysed as passive or active samples. The standard deviations for the new monsoonal calibration (1.25 °C for MAT and 217.7 mm for GSP) are in the same range as those observed for previous calibrations. The new monsoonal calibration was tested using a cross validation procedure. The estimates derived from the new monsoonal calibration (PhysgAsia1) for the Chinese sites are more accurate than those obtained from the Physg3brcAZ calibration, especially for the moisture related parameters. The mean absolute error for GSP of the Chinese sites is 294.6 mm in the new monsoonal calibration, whereas it was 1609.6 mm in the Physg3brcAZ calibration. Results for the three wettest months and three driest months are also more accurate and precise, which allows us to study the seasonality of the precipitation, and hence the monsoon. The new monsoonal calibration also gives accurate results for enthalpy reconstruction. Enthalpy is a parameter that is used for palaeoaltimetry, the new calibration is therefore useful for studies of land surface height changes in

  13. Association of the East Asian subtropical westerly jet with the Southwest Asian summer monsoon: A diagnostic analysis on heavy rain events in Yunnan province, China

    NASA Astrophysics Data System (ADS)

    Chen, Jie

    2016-04-01

    Yunnan province, China is a typical area that is influenced by Southwest Asian summer monsoon (SASM) during boreal summer. Although the interannual variation of summer precipitation in Yunnan Province is closely related to that of the SASM, the East Asian subtropical westerly jet (EASWJ) may have an important role in heavy rainfall events in Yunnan Province during boreal summer. By using daily observations and the NACAR/NCEP data during 1960-2011, a diagnostic analysis is performed to investigate the association of the EASWJ with the SASM on heavy rain events in Yunnan Province during boreal summer. The analysis shows an anomalous divergence circulation pattern at upper level (200 hPa) over Eurasian continent that corresponds well to the negative anomaly of EASWJ during heavy rain events in boreal summer in Yunnan Province. At the same time, a low-level jet stream with abundant water vapor originated from the Arabian Sea and Bengal gulf provides necessarily dynamic and water conditions for heavy rain mechanism. The study further shows that the weakening of the EASWJ during heavy rain events in Yunnan Province is associated with the decrease in the meridional temperature gradient in northern mid-latitude (30o-40o N).

  14. Will the South Asian monsoon overturning circulation stabilize any further?

    NASA Astrophysics Data System (ADS)

    Krishnan, R.; Sabin, T. P.; Ayantika, D. C.; Kitoh, A.; Sugi, M.; Murakami, H.; Turner, A. G.; Slingo, J. M.; Rajendran, K.

    2013-01-01

    Understanding the response of the South Asian monsoon (SAM) system to global climate change is an interesting scientific problem that has enormous implications from the societal viewpoint. While the CMIP3 projections of future changes in monsoon precipitation used in the IPCC AR4 show major uncertainties, there is a growing recognition that the rapid increase of moisture in a warming climate can potentially enhance the stability of the large-scale tropical circulations. In this work, the authors have examined the stability of the SAM circulation based on diagnostic analysis of climate datasets over the past half century; and addressed the issue of likely future changes in the SAM in response to global warming using simulations from an ultra-high resolution (20 km) global climate model. Additional sensitivity experiments using a simplified atmospheric model have been presented to supplement the overall findings. The results here suggest that the intensity of the boreal summer monsoon overturning circulation and the associated southwesterly monsoon flow have significantly weakened during the past 50-years. The weakening trend of the monsoon circulation is further corroborated by a significant decrease in the frequency of moderate-to-heavy monsoon rainfall days and upward vertical velocities particularly over the narrow mountain ranges of the Western Ghats. Based on simulations from the 20-km ultra high-resolution model, it is argued that a stabilization (weakening) of the summer monsoon Hadley-type circulation in response to global warming can potentially lead to a weakened large-scale monsoon flow thereby resulting in weaker vertical velocities and reduced orographic precipitation over the narrow Western Ghat mountains by the end of the twenty-first century. Supplementary experiments using a simplified atmospheric model indicate a high sensitivity of the large-scale monsoon circulation to atmospheric stability in comparison with the effects of condensational heating.

  15. Desert Dust and Monsoon Rain

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.; Kim, Kyu-Myong

    2014-01-01

    For centuries, inhabitants of the Indian subcontinent have know that heavy dust events brought on by strong winds occur frequently in the pre-monsoon season, before the onset of heavy rain. Yet scientists have never seriously considered the possibility that natural dust can affect monsoon rainfall. Up to now, most studies of the impacts of aerosols on Indian monsoon rainfall have focused on anthropogenic aerosols in the context of climate change. However, a few recent studies have show that aerosols from antropogenic and natural sources over the Indian subcontinent may affect the transition from break to active monsoon phases on short timescales of days to weeks. Writing in Nature Geoscience, Vinoj and colleagues describe how they have shown that desert dust aerosols over the Arabian Sea and West Asia can strenghten the summer monsoon over the Indial subcontinent in a matter of days.

  16. Methodology for sensitivity analysis, approximate analysis, and design optimization in CFD for multidisciplinary applications. [computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    Taylor, Arthur C., III; Hou, Gene W.

    1992-01-01

    Fundamental equations of aerodynamic sensitivity analysis and approximate analysis for the two dimensional thin layer Navier-Stokes equations are reviewed, and special boundary condition considerations necessary to apply these equations to isolated lifting airfoils on 'C' and 'O' meshes are discussed in detail. An efficient strategy which is based on the finite element method and an elastic membrane representation of the computational domain is successfully tested, which circumvents the costly 'brute force' method of obtaining grid sensitivity derivatives, and is also useful in mesh regeneration. The issue of turbulence modeling is addressed in a preliminary study. Aerodynamic shape sensitivity derivatives are efficiently calculated, and their accuracy is validated on two viscous test problems, including: (1) internal flow through a double throat nozzle, and (2) external flow over a NACA 4-digit airfoil. An automated aerodynamic design optimization strategy is outlined which includes the use of a design optimization program, an aerodynamic flow analysis code, an aerodynamic sensitivity and approximate analysis code, and a mesh regeneration and grid sensitivity analysis code. Application of the optimization methodology to the two test problems in each case resulted in a new design having a significantly improved performance in the aerodynamic response of interest.

  17. Indo-China monsoon indices.

    PubMed

    Tsai, ChinLeong; Behera, Swadhin K; Waseda, Takuji

    2015-01-29

    Myanmar and Thailand often experience severe droughts and floods that cause irreparable damage to the socio-economy condition of both countries. In this study, the Southeastern Asian Summer Monsoon variation is found to be the main element of interannual precipitation variation of the region, more than the El Niño/Southern Oscillation (ENSO). The ENSO influence is evident only during the boreal spring season. Although the monsoon is the major factor, the existing Indian Monsoon Index (IMI) and Western North Pacific Monsoon Index (WNPMI) do not correlate well with the precipitation variation in the study regions of Southern Myanmar and Thailand. Therefore, a new set of indices is developed based on the regional monsoon variations and presented here for the first time. Precipitation variations in Southern Myanmar and Thailand differ as well as the elements affecting the precipitation variations in different seasons. So, separate indices are proposed for each season for Southern Myanmar and Thailand. Four new monsoon indices based on wind anomalies are formulated and are named as the Indochina Monsoon Indices. These new indices correlate better with the precipitation variations of the study region as compared to the existing IMI and WNPMI.

  18. Indo-China Monsoon Indices

    NASA Astrophysics Data System (ADS)

    Tsai, Chinleong; Behera, Swadhin K.; Waseda, Takuji

    2015-01-01

    Myanmar and Thailand often experience severe droughts and floods that cause irreparable damage to the socio-economy condition of both countries. In this study, the Southeastern Asian Summer Monsoon variation is found to be the main element of interannual precipitation variation of the region, more than the El Niño/Southern Oscillation (ENSO). The ENSO influence is evident only during the boreal spring season. Although the monsoon is the major factor, the existing Indian Monsoon Index (IMI) and Western North Pacific Monsoon Index (WNPMI) do not correlate well with the precipitation variation in the study regions of Southern Myanmar and Thailand. Therefore, a new set of indices is developed based on the regional monsoon variations and presented here for the first time. Precipitation variations in Southern Myanmar and Thailand differ as well as the elements affecting the precipitation variations in different seasons. So, separate indices are proposed for each season for Southern Myanmar and Thailand. Four new monsoon indices based on wind anomalies are formulated and are named as the Indochina Monsoon Indices. These new indices correlate better with the precipitation variations of the study region as compared to the existing IMI and WNPMI.

  19. Effect of dust on the iNdian summer monsoon

    NASA Astrophysics Data System (ADS)

    Maharana, Pyarimohan; Priyadarshan Dimri, Ashok

    2015-04-01

    The atmospheric dust plays a major role in deciding the radiation balance over the earth. The dust scatters the light, acts as cloud condensation nuclei, and hence helps in the formation of different types of clouds. This property of the dust has a long term effect on the Indian summer monsoon and its spatial distribution. India receives around 80% of its annual rainfall during summer monsoon and around 50% of the Indian population depends upon the monsoonal rain for the agricultural activities. The rain also has an important contribution to the industry, water resource management, ground water recharge, provide relief from the heat and also play a major role in deciding the socio-economic condition of a major part of the population. Two sets of simulations (control and dust chemistry simulation) are made to analyze the effect of dust on the Indian summer monsoon. Both the simulations nicely represent the spatial structure of different meteorological parameters. The magnitude of the pressure gradient, circulation and the precipitation is more during the JJAS for the dust chemistry simulation except for the temperature climatology. The analysis of the pre-monsoon and May temperature climatology reflects that the heating of the land mass is more in the dust chemistry simulation as compared to the control simulation, which is providing the strength to the monsoon flow during JJAS. The dust simulation shows that it increases the hydrological cycle over the Indian land mass.

  20. Analysis of time taken to discuss new patients with head and neck cancer in multidisciplinary team meetings.

    PubMed

    Mullan, B J; Brown, J S; Lowe, D; Rogers, S N; Shaw, R J

    2014-02-01

    Multidisciplinary team (MDT) meetings have an important role in the management of head and neck cancer. Increasing incidence of the disease and a drive towards centralised meetings on large numbers of patients mean that effective discussions are pertinent. We aimed to evaluate new cases within a single high volume head and neck cancer MDT and to explore the relation between the time taken to discuss each case, the number of discussants, and type of case. A total of 105 patients with a new diagnosis of head and neck malignancy or complex benign tumour were discussed at 10 head and neck cancer MDT meetings. A single observer timed each discussion using a stopwatch, and recorded the number of discussants and the diagnosis and characteristics of each patient. Timings ranged from 15 to 480 s (8 min) with a mean of 119 s (2 min), and the duration of discussion correlated closely with the number of discussants (rs=0.63, p<0.001). The longest discussions concerned patients with advanced T stage (p=0.006) and advanced N stage (p=0.009) disease, the elderly (p=0.02) and male patients (p=0.05). Tumour site and histological findings were not significant factors in the duration of discussion. Most discussions on patients with early stage tumours were short (T1: 58% less than 60s, mean 90) and fewer people contributed. Many patients, particularly those with early stage disease, require little discussion, and their treatment might reasonably be planned according to an agreed protocol, which would leave more time and resources for those that require greater multidisciplinary input. Further studies may highlight extended discussions on patients with head and neck cancer, which may prompt a review of protocols and current evidence.

  1. Barriers and Challenges in Seeking Psychiatric Intervention in a General Hospital, by the Collaborative Child Response Unit, (A Multidisciplinary Team Approach to Handling Child Abuse) A Qualitative Analysis

    PubMed Central

    Subramaniyan, Vyjayanthi Kanugodu Srinivasa; Mital, Anukant; Rao, Chandrika; Chandra, Girish

    2017-01-01

    Child abuse is a serious criminal act against children in our country and punishable according to protection of children from sexual offenses act 2012. No one agency has the ability to respond completely to the abuse. Hence a multidisciplinary team approach was developed in India. Aim is to narrate the collaborative effort among the multiple disciplines in a general hospital to deliver child protection services and explore the barriers to integrate psychiatric services. Methodology: Members of the team were recruited from different disciplines and trained by experts. A mission statement, protocol to assess the victims and provide treatment was formulated as an algorithm. The barriers to psychiatric treatment among the stakeholders were analyzed using framework method of qualitative analysis. Results (After 20 months) the unit received 27 referrals in 20 months, 24 females, and 3 males. Age of the victims was between 8 months and 17 years. Two cases found to be physically abused. Penetrative sexual abuse was found in 23 cases, pregnant victims were 4. Most referrals were by police, trafficking found in 6 cases. Discussion: It was possible to provide multidisciplinary care to the victims and families. Recurrent themes of barriers to psychiatric treatment were stigma, victim blaming; focus on termination of pregnancy, minimization of abuse in males by stakeholders. Conclusion is collaboration needs more effort to integrate psychiatric services but can minimize the reduplication of services. PMID:28250553

  2. Possible role of pre-monsoon sea surface warming in driving the summer monsoon onset over the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Li, Kuiping; Liu, Yanliang; Yang, Yang; Li, Zhi; Liu, Baochao; Xue, Liang; Yu, Weidong

    2016-08-01

    Sea surface temperature (SST) reaches its annual maximum just before the summer monsoon onset and collapses soon after in the central areas of the Bay of Bengal (BoB). Here, the impact of the peak in the pre-monsoon SST on triggering the earliest monsoon onset in the BoB is investigated, with a focus on the role they play in driving the first-branch northward-propagating intra-seasonal oscillations (FNISOs) over the equatorial Eastern Indian Ocean (EIO). During the calm pre-monsoon period, sea surface warming in the BoB could increase the surface equivalent potential temperature (θe) in several ways. Firstly, warming of the sea surface heats the surface air through sensible heating, which forces the air temperature to follow the SST. The elevated air surface temperature accounts for 30 % of the surface θe growth. Furthermore, the elevated air temperature raises the water vapor capacity of the surface air to accommodate more water vapor. Constrained by the observation that the surface relative humidity is maintained nearly constant during the monsoon transition period, the surface specific humidity exhibits a significant increase, according to the Clausius-Clapeyron relationship. Budget analysis indicates that the additional moisture is primarily obtained from sea surface evaporation, which also exhibits a weak increasing trend due to the sea surface warming. In this way, it contributes about 70 % to the surface θe growth. The rapid SST increase during the pre-monsoon period preconditions the summer monsoon onset over the BoB through its contributions to significantly increase the surface θe, which eventually establishes the meridional asymmetry of the atmospheric convective instability in the EIO. The pre-established greater convective instability leads to the FNISO convections, and the summer monsoon is triggered in the BoB region.

  3. Mesoscale model forecast verification during monsoon 2008

    NASA Astrophysics Data System (ADS)

    Ashrit, Raghavendra; Mohandas, Saji

    2010-08-01

    There have been very few mesoscale modelling studies of the Indian monsoon, with focus on the verification and intercomparison of the operational real time forecasts. With the exception of Das et al (2008), most of the studies in the literature are either the case studies of tropical cyclones and thunderstorms or the sensitivity studies involving physical parameterization or climate simulation studies. Almost all the studies are based on either National Center for Environmental Prediction (NCEP), USA, final analysis fields (NCEP FNL) or the reanalysis data used as initial and lateral boundary conditions for driving the mesoscale model. Here we present a mesoscale model forecast verification and intercomparison study over India involving three mesoscale models: (i) the Weather Research and Forecast (WRF) model developed at the National Center for Atmospheric Research (NCAR), USA, (ii) the MM5 model developed by NCAR, and (iii) the Eta model of the NCEP, USA. The analysis is carried out for the monsoon season, June to September 2008. This study is unique since it is based entirely on the real time global model forecasts of the National Centre for Medium Range Weather Forecasting (NCMRWF) T254 global analysis and forecast system. Based on the evaluation and intercomparison of the mesoscale model forecasts, we recommend the best model for operational real-time forecasts over the Indian region. Although the forecast mean 850 hPa circulation shows realistic monsoon flow and the monsoon trough, the systematic errors over the Arabian Sea indicate an easterly bias to the north (of mean flow) and westerly bias to the south (of mean flow). This suggests that the forecasts feature a southward shift in the monsoon current. The systematic error in the 850 hPa temperature indicates that largely the WRF model forecasts feature warm bias and the MM5 model forecasts feature cold bias. Features common to all the three models include warm bias over northwest India and cold bias over

  4. The Origins of ITCZs, Monsoons, and Monsoon Onset

    NASA Technical Reports Server (NTRS)

    Chao, Winston C.

    2009-01-01

    Intertropical convergence zones (ITCZs), monsoons and monsoon onset are among the most prominent of atmospheric phenomena. Understanding their origins is fundamental to a full understanding of the atmospheric general circulation and has challenged meteorologists for a very long time. There has been important progress in understanding these phenomena in recent years, and in this seminar, recent developments, to which the speaker has contributed, are reviewed. First, contrary to conventional belief, land-sea thermal contrast is not necessary for monsoons to form. Second, monsoon onset occurs when there is a sudden poleward jump of an ITCZ during its annual cycle of latitudinal movement. A monsoon, then, is an ITCZ after its poleward jump. Third, the SST latitudinal maximum is not the most significant, or even a necessary, factor in the formation of an ITCZ; there are other important, if not more important, factors. These factors are the interaction between convection and surface fluxes, the interaction between convection and radiation, and the earth's rotation. Finally, the recent understanding of how ITCZs form has led to a conceptual explanation for the origin of the double ITCZ bias in GCM simulations.

  5. Summer monsoon onset-induced changes of autotrophic pico- and nanoplankton in the largest monsoonal estuary along the west coast of India.

    PubMed

    Mohan, Arya P; Jyothibabu, R; Jagadeesan, L; Lallu, K R; Karnan, C

    2016-02-01

    This study presents the response of autotrophic pico- and nanoplankton to southwest monsoon-associated hydrographical transformations in the Cochin backwaters (CBW), the largest monsoonal estuary along the west coast of India. By the onset of the southwest monsoon, the euhaline/mesohaline conditions in the downstream/upstream of CBW usually transform into oligohaline/limnohaline. The flow cytometer analysis revealed the dominance of picoeukaryotes > Synechococcus > nanoautotrophs, with Prochlorococcus either very low or entirely absent. Synechococcus abundance was high during the pre-southwest monsoon (10(6) L(-1)), which dwindled with heavy fresh water influx during the southwest monsoon (10(5) L(-1)). The drastic drop in salinity and faster flushing of the CBW during the southwest monsoon replaced the euhaline/mesohaline strain of Synechococcus with an oligohaline/limnohaline strain. Epifluorescence microscopy analyses showed that, among the two strains of Synechococcus, the phycoerythrin-rich (PE-rich) one was dominant in the mesohaline/euhaline conditions, whereas the phycocyanin-rich (PC-rich) strain dominated in oligohaline/limnohaline conditions. Although Synechococcus abundance diminished during the southwest monsoon, the total abundance of picoplankton community remained virtually unchanged in the upstream due to an increase in the abundance of picoeukaryotes. On the other hand, the autotrophic nanoplankton abundance increased from pre-monsoon levels of av. 3.8 × 10(6)-av. 9.5 × 10(6) L(-1) at the onset of the southwest monsoon. Utilizing suitable multivariate analyses, the study illustrated the differential response and niche preference of various smaller communities of autotrophs to the southwest monsoon-associated hydrographical ramifications in a large monsoonal estuary, which may be applicable to similar such estuaries situated along the Indian coastline.

  6. A Review of the Multidisciplinary Diagnosis of Interstitial Lung Diseases: A Retrospective Analysis in a Single UK Specialist Centre

    PubMed Central

    Chaudhuri, Nazia; Spencer, Lisa; Greaves, Melanie; Bishop, Paul; Chaturvedi, Anshuman; Leonard, Colm

    2016-01-01

    The accurate diagnosis and management of individuals with interstitial lung diseases (ILDs) poses an interesting challenge in clinical practice. A multidisciplinary team (MDT) approach is considered the gold standard. This is a single-centre retrospective review spanning a five-year period. We assessed the accuracy of prior ILD diagnosis, the methodology used to establish a correct diagnosis and how an MDT approach affected subsequent management. Our data supports an MDT approach in an experienced specialist ILD centre. We have demonstrated that diagnosis is often changed after an MDT review and that this impacts the subsequent management. Our results demonstrate that an MDT approach to diagnosis can establish a diagnosis in the majority of cases when prior diagnosis is uncertain (76%). We also show that a prior diagnosis of idiopathic pulmonary fibrosis is deemed inaccurate in over 50% of cases after MDT discussion. We have shown that during diagnostic uncertainty the considered gold standard of proceeding to a lung biopsy is not always feasible due to disease severity and comorbidities. In these circumstances, an MDT approach to diagnosis of ILDs combines clinical data with serial lung function and disease behavior, with or without responses to previous treatment trials to establish an accurate expert diagnosis. PMID:27472372

  7. Integrating Multidisciplinary Engineering Knowledge

    ERIC Educational Resources Information Center

    Wolff, Karin; Luckett, Kathy

    2013-01-01

    In order to design two distinct engineering qualification levels for an existing University of Technology programme, empirical evidence based on the current diploma is necessary to illuminate the nature of and the relationship between the "contextual" and "conceptual" elements underpinning a multidisciplinary engineering…

  8. Analysis of the linkages between rainfall and land surface conditions in the West African monsoon through CMAP, ERS-WSC, and NOAA-AVHRR data

    NASA Astrophysics Data System (ADS)

    Philippon, Nathalie; Mougin, Eric; Jarlan, Lionel; Frison, Pierre-Louis

    2005-12-01

    The European Remote Sensing Wind Scatterometer (ERS-WSC) backscattering coefficient, NOAA Advanced Very High Resolution Radiometer (NOAA-AVHRR) Normalized Difference Vegetation Index (NDVI), and Climate Prediction Center Merged Analysis Precipitation (CMAP) precipitation data sets are studied over the period August 1991 to December 2000 to document (1) the interannual and intra-annual evolutions of vegetation photosynthetic activity and soil-vegetation water content over West Africa and (2) their two-way links with precipitation. Over the Sahel, at interannual timescales the strongest relationships between vegetation, soil moisture, and precipitation are observed from July to October and when 1-month lag is considered between the parameters. This delay reflects the vegetation response time to the moisture pulses that follow precipitation events. The high correlation between NDVI and sigma_0 at interannual timescales confirms the importance of vegetation in the backscattering coefficient. However, sigma_0 shows stronger statistical links with precipitation, suggesting that this product contains additional useful information related in particular to upper soil moisture. Over Guinea, large differences are observed between the two remote sensing products, and their relationship with precipitation at interannual timescales is weaker. Sigma_0 is significantly linked to precipitation from July to November, whereas NDVI does not show any significant relationship with precipitation. NDVI and sigma_0 serial correlations over the Sahel and Guinea suggest that a 2-month memory usually characterizes vegetation photosynthetic activity and soil-vegetation water content anomalies. However, anomalies disappearance in winter then reappearance in the following spring also suggests an interseason memory held by deep soil moisture reservoirs and deep-rooted plants. A composite analysis reveals that the wettest Sahelian rainy seasons were preceded by positive anomalies of soil

  9. Investigation of summer monsoon rainfall variability in Pakistan

    NASA Astrophysics Data System (ADS)

    Hussain, Mian Sabir; Lee, Seungho

    2016-08-01

    This study analyzes the inter-annual and intra-seasonal rainfall variability in Pakistan using daily rainfall data during the summer monsoon season (June to September) recorded from 1980 to 2014. The variability in inter-annual monsoon rainfall ranges from 20 % in northeastern regions to 65 % in southwestern regions of Pakistan. The analysis reveals that the transition of the negative and positive anomalies was not uniform in the investigated dataset. In order to acquire broad observations of the intra-seasonal variability, an objective criterion, the pre-active period, active period and post-active periods of the summer monsoon rainfall have demarcated. The analysis also reveals that the rainfall in June has no significant contribution to the increase in intra-seasonal rainfall in Pakistan. The rainfall has, however, been enhanced in the summer monsoon in August. The rainfall of September demonstrates a sharp decrease, resulting in a high variability in the summer monsoon season. A detailed examination of the intra-seasonal rainfall also reveals frequent amplitude from late July to early August. The daily normal rainfall fluctuates significantly with its maximum in the Murree hills and its minimum in the northwestern Baluchistan.

  10. Multidisciplinary team meetings in Oncology: first analysis of benefits and evaluation of activity in a Dermatology unit in France.

    PubMed

    Caudron, Anne; Chaby, Guillaume; Dadban, Ali; Andrejak, Claire; Dhaille, Florie; Bagot, Martine; Lok, Catherine

    2010-01-01

    Improving Multi-Disciplinary Meetings (MDM) is one of the 70 clauses of the French Cancer Plan of 2003-2007. The French High Authority of Health (HAS) and the National Cancer Institute (INCa) have established guidelines to standardize MDM concerning cancer care. No objective assessment of cutaneous cancer (dermato-oncology) MDM has been published yet, despite the growing numbers in the incidence of skin cancers. This study aims to analyze two of our center's MDM concerns: its decisions and its compliance with HAS guidelines. A retrospective study of all skin tumors discussed in MDM held at Amiens University Hospital between 2006-2007 analyzed epidemiological data, MDM decisions (recommendations), and their compliance. 349 MDM conclusion reports concerning 228 patients were analyzed. The cases consisted of 132 melanomas, 27 basal cell carcinomas, 19 squamous cell carcinomas, 5 Merkel cell carcinomas, 8 sarcomas, 16 cutaneous lymphomas, and 21 other tumors. 45.7% of MDM had at least 3 different specialists present. Patients were present in 49.4% of discussions. 88% of the MDMs' recommendations were implemented. More than 94% of these decisions were according to the guidelines. MDM recommendations contributed to: making 13.6% of diagnoses, 74.7% of treatment decisions, 45.6% of investigations requested, and 48.2% of long-term follow-up decisions. Treatment recommendations were: surgery in 50.6% of patients, chemotherapy in 45.0% and radiotherapy in 12.5%. The MDM's therapeutic decisions tended to follow the specialty of the referring physician; e.g. patients were likely to have surgery when referred by a surgeon, etc (p < 0.0001). Dermato-oncology MDM at Amiens University Hospital comply with most of the guidelines, however, patient attendance at MDM, participation of different specialists and the formal function and structure, all have room for improvement.

  11. Anti-phase relationship between the East Asian winter monsoon and summer monsoon during the Holocene?

    NASA Astrophysics Data System (ADS)

    Ge, Qian; Xue, Zuo; Yao, Zhigang; Zang, Zhengchen; Chu, Fengyou

    2017-04-01

    The relationship between the East Asian winter monsoon (EAWM) and East Asian summer monsoon (EASM) during the Holocene is complicated and remains controversial. In this study, analysis of grain size and benthic foraminiferal oxygen isotope, as well as accelerator mass spectrometry 14C dating was performed on a sediment core retrieved from the newly revealed muddy deposit on the northern South China Sea continental shelf. The history of the EAWM and EASM were reconstructed for the last 8200 a BP. Further analysis in conjunction with previously published paleo-climate proxies revealed that the relationship between the EAWM and EASM during the Holocene is more complex than a simple and strict anti-phase one-both negative and positive correlations were identified. The EAWM and EASM are negatively correlated around 7500, 4800, 4200, 3200, and 300 a BP (cooling periods), while positively correlated around 7100, 3700, and 2100 a BP (warm periods). In particular, both the EAWM and EASM intensified during the three positive correlation periods. However, we also found that the relationship between these two sub-monsoons is anti-phase during the final phase of particularly hot periods like Holocene Optimum and Medieval warm period. The possible impact from variations of solar irradiance on the relationship between the EAWM and EASM was also discussed.

  12. Testing a flexible method to reduce false monsoon onsets.

    PubMed

    Stiller-Reeve, Mathew Alexander; Spengler, Thomas; Chu, Pao-Shin

    2014-01-01

    To generate information about the monsoon onset and withdrawal we have to choose a monsoon definition and apply it to data. One problem that arises is that false monsoon onsets can hamper our analysis, which is often alleviated by smoothing the data in time or space. Another problem is that local communities or stakeholder groups may define the monsoon differently. We therefore aim to develop a technique that reduces false onsets for high-resolution gridded data, while also being flexible for different requirements that can be tailored to particular end-users. In this study, we explain how we developed our technique and demonstrate how it successfully reduces false onsets and withdrawals. The presented results yield improved information about the monsoon length and its interannual variability. Due to this improvement, we are able to extract information from higher resolution data sets. This implies that we can potentially get a more detailed picture of local climate variations that can be used in more local climate application projects such as community-based adaptations.

  13. Examining Impact of Global warming on the summer monsoon system using regional Climate Model (PRECIS)

    NASA Astrophysics Data System (ADS)

    Patwardhan, S. K.; Kundeti, K.; Krishna Kumar, K.

    2011-12-01

    Every year, southwest monsoon arrives over Indian region with remarkable regularity. It hits the southern state of Kerala first by the end of May or the early June. More than 70% of the annual precipitation is received during the four monsoon months viz. June to September. This monsoon rainfall is vital for the agriculture as well as for the yearly needs of Indian population. The performance of the monsoon depends on the timely onset over southern tip of India and its progress along the entire country. This northward progression of monsoon to cover the entire Indian landmass, many times, is associated with the formation of synoptic scale system in the Bay of Bengal region and their movement along the monsoon trough region. The analysis of the observed cyclonic disturbances show that their frequency has reduced in recent decades. It is, therefore, necessary to assess the effect of global warming on the monsoon climate of India. A state-of-art regional climate modelling system, known as PRECIS (Providing REgional Climates for Impacts Studies) developed by the Hadley Centre for Climate Prediction and Research, U.K. is applied over the South Asian domain to investigate the impact of global warming on the cyclonic disturbances. The PRECIS simulations at 50 km x 50 km horizontal resolution are made for two time slices, present (1961-1990) and the future (2071-2100), for two socio-economic scenarios A2 and B2. The model skills are evaluated using observed precipitation and surface air temperature. The model has shown reasonably good skill in simulating seasonal monsoon rainfall, whereas cold bias is seen in surface air temperature especially in post-monsoon months. The typical monsoon features like monsoon trough, precipitation maxima over west coast and northeast India are well simulated by the model. The model simulations under the scenarios of increasing greenhouse gas concentrations and sulphate aerosols are analysed to study the likely changes in the quasi

  14. Monsoon low-level jet over the gateway of Indian summer monsoon: a comparative study for two distinct monsoon years

    NASA Astrophysics Data System (ADS)

    Narayanan, Suresh; Kottayil, Ajil; Mohanakumar, K.

    2016-12-01

    High-resolution radiosonde measurements are used to study the characteristics and dynamics of monsoon low-level jet at the monsoon onset region of Cochin (10.04°N; 76.32°E) in India under two contrasting monsoon years, 2013 and 2015. The core speed and core height of the low-level jet is significantly higher during the strong monsoon year of 2013 than for the monsoon-deficient year of 2015. The average core heights for these years are seen to exist at 2.03 and 2.20 km, respectively. The low-level jet-modulated parameters such as moisture flux, momentum flux and kinetic energy flux show higher values during monsoon of 2013 as compared to 2015. Among the monsoon low-level jet parameters, the moisture flux has the strongest influence on the observed rainfall over Cochin. Also, an exponential function is seen to best explain the moisture flux-rainfall relationship. The weakening of monsoon during 2015 is attributed most likely to an eastward shift of the core convective activity from the Indian subcontinent as revealed from satellite observation of the upper tropospheric humidity. A close association is seen between the rainfall over Cochin and the convective activity over the Indian subcontinent. Observational studies such as this, which links monsoon rainfall, monsoon low-level jet parameters and convective activity, are expected to enhance the understanding of monsoon processes in general and subsequently improve the forecasting skill of models.

  15. The relationship between Arabian Sea upwelling and Indian Monsoon revisited

    NASA Astrophysics Data System (ADS)

    Yi, Xing; Zorita, Eduardo; Hünicke, Birgit

    2015-04-01

    Coastal upwelling is important to marine ecosystems and human activities. It transports nutrient-rich deep water mass that supports marine biological productivity. In this study, we aim to characterize the large-scale climate forcings that drive upwelling along the western Arabian Sea coast. Studies based on ocean sediments suggest that there is a link between this coastal upwelling system and the Indian summer monsoon. However, a more direct method is needed to examine the influence of various forcings on upwelling. For this purpose, we analyse a high-resolution (about 10 km) global ocean simulation (denoted STORM), which is based on the MPI-OM model developed by the Max-Planck-Institute for Meteorology in Hamburg driven by the global meteorological reanalysis NCEP over the period 1950-2010. This very high spatial resolution allows us to identify characteristics of the coastal upwelling system. We compare the simulated upwelling velocity of STORM with two traditional upwelling indices: along-shore wind speed and sea surface temperature. The analysis reveals good consistency between these variables, with high correlations between coastal upwelling and along-shore wind speed (r=0.85) as well as coastal sea surface temperature (r=-0.77). To study the impact of the monsoon on the upwelling we analyse both temporal and spatial co-variability between upwelling velocity and the Indian summer monsoon index. The spatial analysis shows that the impact of the monsoon on the upwelling is concentrated along the coast, as expected. However, somewhat unexpectedly, the temporal correlation between the coastal upwelling and the monsoon index is rather weak (r=0.26). Also, the spatial structure of upwelling in the Arabian Sea as revealed by a Principal Component Analysis is rather rich, indicating that factors other than the Monsoon are also important drivers of upwelling. In addition, no detectable trend in our coastal upwelling is found in the simulation that would match the

  16. Multidisciplinary Concurrent Design Optimization via the Internet

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.; Kelkar, Atul G.; Koganti, Gopichand

    2001-01-01

    A methodology is presented which uses commercial design and analysis software and the Internet to perform concurrent multidisciplinary optimization. The methodology provides a means to develop multidisciplinary designs without requiring that all software be accessible from the same local network. The procedures are amenable to design and development teams whose members, expertise and respective software are not geographically located together. This methodology facilitates multidisciplinary teams working concurrently on a design problem of common interest. Partition of design software to different machines allows each constituent software to be used on the machine that provides the most economy and efficiency. The methodology is demonstrated on the concurrent design of a spacecraft structure and attitude control system. Results are compared to those derived from performing the design with an autonomous FORTRAN program.

  17. Multiscale Variability of the Monsoon Climate

    NASA Astrophysics Data System (ADS)

    Krishnamurthy, V.

    2005-05-01

    The reliability of weather forecasts is limited to a few days and is mainly determined by the synoptic scale features of the atmosphere. The predictability of weather models depends on the error growth determined by nonlinear terms representing advection. Smaller scale features, such as convection, may also influence the predictability of the synoptic scale forecasts. While the prediction of instantaneous states of the system may be impossible on longer time scale, there is optimism for medium-range and long-range forecasts of time-averaged features of the climate system. Such optimism is based on the observation that slowly-varying boundary forces such as sea surface temperature, soil moisture and snow influence the variability of the atmosphere on a longer time scale, especially in the tropical region. This study discusses the variability of such a tropical climate system, the monsoon, and shows that its variability consists of a combination of large-scale persistent seasonal mean component and intraseasonal variability of different time scales. The spatial variability of these components is also found to consist of different scales. By performing multi-channel singular spectrum analysis of daily rainfall, low-pressure systems, outgoing long-wave radiation and winds, two oscillatory modes with periods of about 45 and 20 days have been identified and shown to correspond to the active and break phases of the monsoon. These two intraseasonal modes, however, do not contribute much to the seasonal mean rainfall. Three other components of the MSSA are identified as the contributors to the seasonal mean rainfall, possibly arising from the influence of slowly-varying boundary forces. The prospect for making accurate long-range forecasts of the monsoon depends on the relative magnitudes of the large-scale seasonally persistent component and the intraseasonal component and on climate model experiments to establish a relation between the two components.

  18. See-saw relationship of the Holocene East Asian-Australian summer monsoon.

    PubMed

    Eroglu, Deniz; McRobie, Fiona H; Ozken, Ibrahim; Stemler, Thomas; Wyrwoll, Karl-Heinz; Breitenbach, Sebastian F M; Marwan, Norbert; Kurths, Jürgen

    2016-09-26

    The East Asian-Indonesian-Australian summer monsoon (EAIASM) links the Earth's hemispheres and provides a heat source that drives global circulation. At seasonal and inter-seasonal timescales, the summer monsoon of one hemisphere is linked via outflows from the winter monsoon of the opposing hemisphere. Long-term phase relationships between the East Asian summer monsoon (EASM) and the Indonesian-Australian summer monsoon (IASM) are poorly understood, raising questions of long-term adjustments to future greenhouse-triggered climate change and whether these changes could 'lock in' possible IASM and EASM phase relationships in a region dependent on monsoonal rainfall. Here we show that a newly developed nonlinear time series analysis technique allows confident identification of strong versus weak monsoon phases at millennial to sub-centennial timescales. We find a see-saw relationship over the last 9,000 years-with strong and weak monsoons opposingly phased and triggered by solar variations. Our results provide insights into centennial- to millennial-scale relationships within the wider EAIASM regime.

  19. See–saw relationship of the Holocene East Asian–Australian summer monsoon

    PubMed Central

    Eroglu, Deniz; McRobie, Fiona H.; Ozken, Ibrahim; Stemler, Thomas; Wyrwoll, Karl-Heinz; Breitenbach, Sebastian F. M.; Marwan, Norbert; Kurths, Jürgen

    2016-01-01

    The East Asian–Indonesian–Australian summer monsoon (EAIASM) links the Earth's hemispheres and provides a heat source that drives global circulation. At seasonal and inter-seasonal timescales, the summer monsoon of one hemisphere is linked via outflows from the winter monsoon of the opposing hemisphere. Long-term phase relationships between the East Asian summer monsoon (EASM) and the Indonesian–Australian summer monsoon (IASM) are poorly understood, raising questions of long-term adjustments to future greenhouse-triggered climate change and whether these changes could ‘lock in' possible IASM and EASM phase relationships in a region dependent on monsoonal rainfall. Here we show that a newly developed nonlinear time series analysis technique allows confident identification of strong versus weak monsoon phases at millennial to sub-centennial timescales. We find a see–saw relationship over the last 9,000 years—with strong and weak monsoons opposingly phased and triggered by solar variations. Our results provide insights into centennial- to millennial-scale relationships within the wider EAIASM regime. PMID:27666662

  20. Recent and future changes in the Asian monsoon-ENSO relationship: Natural or forced?

    NASA Astrophysics Data System (ADS)

    Li, Xiaoqiong; Ting, Mingfang

    2015-05-01

    The Asian monsoon-ENSO (El Niño-Southern Oscillation) relationship in the 20th and 21st centuries is examined using observations and Coupled Model Intercomparison Project Phase 5 (CMIP5) model simulations. CMIP5 models can simulate the ENSO-monsoon spatial structure reasonably well when using the multimodel mean. Running correlations show prominent decadal variability of the ENSO-monsoon relationship in observations. The modeled ENSO-monsoon relation shows large intermodel spread, indicating large variations across the model ensemble. The anthropogenically forced component of ENSO-monsoon relationship is separated from the naturally varying component based on a signal-to-noise maximizing empirical orthogonal function analysis using global sea surface temperature (SST). Results show that natural variability plays a dominant role in the varied ENSO-monsoon relationship during the 20th century. In the 21st century, the forced component is dominated by enhanced monsoon rainfall associated with SST warming, which may contribute to a slightly weakened ENSO-monsoon relation in the future.

  1. Multidisciplinary audit of digoxin.

    PubMed

    Keys, P W; DeSantis, D; Duffy, M G

    1978-08-01

    Use review of digoxin as part of a medical care evaluation study in a hospital is described. This drug audit within the hospital's quality assurance program used a multidisciplinary approach. The study was designed to measure the incidence of digoxin toxicity, evaluate monitoring practices for digoxin use and evaluate the adequacy of digoxin dosing patterns. Forty-eight patients were involved. Results indicated that some patients were not adequately assessed in regard to renal function and digoxin serum level. Further, there was a 17% incidence of digoxin toxicity. Studies such as this give pharmacists an opportunity to use their knowledge of proper drug use through a structured hospital program.

  2. Multi-Scale Predictions of the Asian Monsoons in the NCEP Climate Forecast System

    NASA Astrophysics Data System (ADS)

    Yang, S.

    2013-12-01

    A comprehensive analysis of the major features of the Asian monsoon system in the NCEP Climate Forecast System version 2 (CFSv2) and predictions of the monsoon by the model has been conducted. The intraseasonal-to-interannual variations of both summer monsoon and winter monsoon, as well as the annual cycles of monsoon climate, are focused. Features of regional monsoons including the monsoon phenomena over South Asia, East Asia, and Southeast Asia are discussed. The quasi-biweekly oscillation over tropical Asia and the Mei-yu climate over East Asia are also investigated. Several aspects of monsoon features including the relationships between monsoon and ENSO (including different types of ENSO: eastern Pacific warming and central Pacific warming), extratropical effects, dependence on time leads (initial conditions), regional monsoon features, and comparison between CFSv2 and CFS version 1 (CFSv1) are particularly emphasized. Large-scale characteristics of the Asian summer monsoon including several major dynamical monsoon indices and their associated precipitation patterns can be predicted several months in advance. The skill of predictions of the monsoon originates mostly from the impact of ENSO. It is found that large predictability errors occur in first three lead months and they only change slightly as lead time increases. The large errors in the first three lead months are associated with the large errors in surface thermal condition and atmospheric circulation in the central and eastern Pacific and the African continent. In addition, the response of the summer monsoon to ENSO becomes stronger with increase in lead time. The CFSv2 successfully simulates several major features of the East Asian winter monsoon and its relationships with the Arctic Oscillation, the East Asian subtropical jet, the East Asian trough, the Siberian high, and the lower-tropospheric winds. Surprisingly, the upper-tropospheric winds over the middle-high latitudes can be better simulated

  3. Ice-sheet influences on global Monsoon systems (Invited)

    NASA Astrophysics Data System (ADS)

    Timmermann, A.; Elison Timm, O.; Friedrich, T.; Abe-Ouchi, A.; Menviel, L.; Tigchelaar, M.

    2013-12-01

    The waxing and waning of the northern Hemisphere ice-sheets on orbital and millennial timescales and corresponding changes in atmospheric and oceanic circulation played an essential role in modulating monsoon systems globally. Here we review the mechanisms by which changes in ice-sheet orography, global sea-level and freshwater input into the North Atlantic can influence global wind patterns and tropical moisture convergence. Our analysis is based on a series of transient model simulations conducted with the newly developed 3-dimensional coupled ice-sheet-climate model iLOVE. Forced by orbital and greenhouse gas concentrations over the past 80 ka, this model realistically simulates the evolution of Northern Hemisphere ice volume. It is demonstrated that orbital-scale changes in ice-sheet orography influence the South American and African Monsoons, but leave Asian Monsoon systems relatively unaltered. On millennial timescales the situation is very different. Freshwater forcing from calving ice-sheets causes variations of the thermohaline circulation, North Atlantic sea surface temperatures and global wind patterns. Using an earth system model hindcast for the period 30-50 ka in combination with high-resolution hydroclimate proxies, we demonstrate that this mechanism can explain for the bulk of MIS3 global Monsoon variability on millennial-timescales. In addition to these remote influences, rainfall intensity in the dominant Monsoon regions is also modulated by precessional forcing and corresponding shifts of the meridional surface temperature gradients. This presentation will conclude with a brief discussion of gaps in our understanding of how orbital forcing affected Monsoons and Intertropical Convergence Zones during the Pleistocene.

  4. Halitosis: the multidisciplinary approach

    PubMed Central

    Bollen, Curd ML; Beikler, Thomas

    2012-01-01

    Halitosis, bad breath or oral malodour are all synonyms for the same pathology. Halitosis has a large social and economic impact. For the majority of patients suffering from bad breath, it causes embarrassment and affects their social communication and life. Moreover, halitosis can be indicative of underlying diseases. Only a limited number of scientific publications were presented in this field until 1995. Ever since, a large amount of research is published, often with lack of evidence. In general, intraoral conditions, like insufficient dental hygiene, periodontitis or tongue coating are considered to be the most important cause (85%) for halitosis. Therefore, dentists and periodontologists are the first-line professionals to be confronted with this problem. They should be well aware of the origin, the detection and especially of the treatment of this pathology. In addition, ear–nose–throat-associated (10%) or gastrointestinal/endocrinological (5%) disorders may contribute to the problem. In the case of halitophobia, psychiatrical or psychological problems may be present. Bad breath needs a multidisciplinary team approach: dentists, periodontologists, specialists in family medicine, ear–nose–throat surgeons, internal medicine and psychiatry need to be updated in this field, which still is surrounded by a large taboo. Multidisciplinary bad breath clinics offer the best environment to examine and treat this pathology that affects around 25% of the whole population. This article describes the origin, detection and treatment of halitosis, regarded from the different etiological origins. PMID:22722640

  5. Indian Monsoon Depression: Climatology and Variability

    SciTech Connect

    Yoon, Jin-Ho; Huang, Wan-Ru

    2012-03-09

    The monsoon climate is traditionally characterized by large seasonal rainfall and reversal of wind direction (e.g., Krishnamurti 1979). Most importantly this rainfall is the major source of fresh water to various human activities such as agriculture. The Indian subcontinent resides at the core of the Southeast Asian summer monsoon system, with the monsoon trough extended from northern India across Indochina to the Western Tropical Pacific (WTP). Large fraction of annual rainfall occurs during the summer monsoon season, i.e., June - August with two distinct maxima. One is located over the Bay of Bengal with rainfall extending northwestward into eastern and central India, and the other along the west coast of India where the lower level moist wind meets the Western Ghat Mountains (Saha and Bavardeckar 1976). The rest of the Indian subcontinent receives relatively less rainfall. Various weather systems such as tropical cyclones and weak disturbances contribute to monsoon rainfall (Ramage 1971). Among these systems, the most efficient rain-producing system is known as the Indian monsoon depression (hereafter MD). This MD is critical for monsoon rainfall because: (i) it occurs about six times during each summer monsoon season, (ii) it propagates deeply into the continent and produces large amounts of rainfall along its track, and (iii) about half of the monsoon rainfall is contributed to by the MDs (e.g., Krishnamurti 1979). Therefore, understanding various properties of the MD is a key towards comprehending the veracity of the Indian summer monsoon and especially its hydrological process.

  6. The Multi-Disciplinary Graduate Program in Educational Research. Final Report, Part III; Elements of Panel Analysis.

    ERIC Educational Resources Information Center

    Lazarsfeld, Paul F., Ed.

    Four case studies were used to illustrate application of panel analysis in sociological research. The panel design requires that (a) identical units be reobserved; (b) identical criteria be employed; and (c) initial and subsequent observations be made at the same times for all units and all criteria. Units may be individuals, qroups (such as…

  7. Scarab -a Multi-Disciplinary Code for Destruction Analysis of Space-Craft during Re-Entry

    NASA Astrophysics Data System (ADS)

    Koppenwallner, G.; Fritsche, B.; Lips, T.; Klinkrad, H.

    2005-02-01

    The uncontrolled, destructive re-entry of satellites and the related ground risk due to fragments reaching the ground have become of increased interest during the past years. The software system SCARAB (Spacecraft Atmospheric Re-entry and Aerothermal Break-up) is designed to calculate the destruction of a spacecraft during re-entry. Development of this code system started in 1995 and was conducted by HTG within the frame of various ESOC contracts with ITAM in Novosibirsk as continuous partner. The modular software system provide modules for satellite modelling and re-entry analysis The analysis modules combine aerodynamic/aero-thermal loads, 6-D flight dynamic, heat conduction, destruction by melting or fracture and the fragment tracking till ground impact SCARAB has been applied to many projects like ARIANE 5, ATV, ROSAT, Beppo SAX and Terrasar.

  8. From Systems Understanding to Personalized Medicine: Lessons and Recommendations Based on a Multidisciplinary and Translational Analysis of COPD.

    PubMed

    Roca, Josep; Cano, Isaac; Gomez-Cabrero, David; Tegnér, Jesper

    2016-01-01

    Systems medicine, using and adapting methods and approaches as developed within systems biology, promises to be essential in ongoing efforts of realizing and implementing personalized medicine in clinical practice and research. Here we review and critically assess these opportunities and challenges using our work on COPD as a case study. We find that there are significant unresolved biomedical challenges in how to unravel complex multifactorial components in disease initiation and progression producing different clinical phenotypes. Yet, while such a systems understanding of COPD is necessary, there are other auxiliary challenges that need to be addressed in concert with a systems analysis of COPD. These include information and communication technology (ICT)-related issues such as data harmonization, systematic handling of knowledge, computational modeling, and importantly their translation and support of clinical practice. For example, clinical decision-support systems need a seamless integration with new models and knowledge as systems analysis of COPD continues to develop. Our experience with clinical implementation of systems medicine targeting COPD highlights the need for a change of management including design of appropriate business models and adoption of ICT providing and supporting organizational interoperability among professional teams across healthcare tiers, working around the patient. In conclusion, in our hands the scope and efforts of systems medicine need to concurrently consider these aspects of clinical implementation, which inherently drives the selection of the most relevant and urgent issues and methods that need further development in a systems analysis of disease.

  9. Western North Pacific monsoon depressions: Transitions to pre-tropical cyclone seedlings

    NASA Astrophysics Data System (ADS)

    Beattie, Jodi C.; Elsberry, Russell L.

    2016-11-01

    The objective of this study is to describe how a monsoon depression in the western North Pacific, which typically has a diameter of 1000 km, may be transitioned into a tropical cyclone with an inner core of strong winds and deep convection on the order of 100 km. Our previous case study of the pre-Typhoon Man-Yi monsoon depression formation is extended to show that the same cross-equatorial airstream continued and led to enhanced equatorial westerlies on the equatorward side of the pre-Man-Yi circulation, and a surge in the trade easterlies was also present on the poleward side. As these surges in the near-equatorial flow are inertially unstable, inward-directed wave-activity fluxes then led to flux convergence over the eastern vorticity maximum of the monsoon depression, which resulted in a scale contraction to that of a pretropical cyclone seedling. Eight case studies of the transitions of monsoon depressions during 2009 are presented that document persistent inward-directed wave-activity fluxes over a vorticity maximum within the monsoon depression is a key feature of each transition. In some transitions, the same cross-equatorial airstream as led to the monsoon depression formation continues as the primary airstream, and in other transitions another airstream to the west or enhanced tropical easterlies become the primary airstream. Analysis of 10 non-transitioning monsoon depressions during 2009 indicated the airstream wave-activity flux did not persist after the formation of the monsoon depression. In another 11 non-transitioning monsoon depressions, the inward-directed wave-activity flux was small and no region of wave-activity flux convergence was associated with the vorticity maximum in the monsoon depression.

  10. A Mesoscale Analysis of Column-Integrated Aerosol Properties in Northern India During the TIGERZ 2008 Pre-Monsoon Period and a Comparison to MODIS Retrievals

    NASA Technical Reports Server (NTRS)

    Giles, D. M.; Holben, B. N.; Tripathi, S. N.; Eck, T. F.; Newcomb, W. W.; Slutsker, I.; Dickerson, R. R.; Thompson, A. M.; Wang, S.-H.; Singh, R. P.; Sinyuk, A.

    2010-01-01

    opportunity to measure the spatial and temporal variations of aerosol loading in the IGP. The strong aerosol absorption derived from ground-based sun/sky radiometer measurements suggested the presence of a predominately black carbon and dust mixture during the pre-monsoon period. Consistent with the elevated heat-pump hypothesis, these absorbing aerosols found across Kanpur and the greater IGP region during the pre-monsoon period likely induced regional atmospheric warming, which lead to a more rapid advance of the southwest Asian monsoon and above normal precipitation over northern India in June 2008.

  11. Multidisciplinary Optimization Methods for Aircraft Preliminary Design

    NASA Technical Reports Server (NTRS)

    Kroo, Ilan; Altus, Steve; Braun, Robert; Gage, Peter; Sobieski, Ian

    1994-01-01

    This paper describes a research program aimed at improved methods for multidisciplinary design and optimization of large-scale aeronautical systems. The research involves new approaches to system decomposition, interdisciplinary communication, and methods of exploiting coarse-grained parallelism for analysis and optimization. A new architecture, that involves a tight coupling between optimization and analysis, is intended to improve efficiency while simplifying the structure of multidisciplinary, computation-intensive design problems involving many analysis disciplines and perhaps hundreds of design variables. Work in two areas is described here: system decomposition using compatibility constraints to simplify the analysis structure and take advantage of coarse-grained parallelism; and collaborative optimization, a decomposition of the optimization process to permit parallel design and to simplify interdisciplinary communication requirements.

  12. Monsoon-Enso Relationships: A New Paradigm

    NASA Technical Reports Server (NTRS)

    Lau, K. M.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    This article is partly a review and partly a new research paper on monsoon-ENSO relationship. The paper begins with a discussion of the basic relationship between the Indian monsoon and ENSO dating back to the work of Sir Gilbert Walker up to research results in more recent years. Various factors that may affect the monsoon-ENSO, relationship, including regional coupled ocean-atmosphere processes, Eurasian snow cover, land-atmosphere hydrologic feedback, intraseasonal oscillation, biennial variability and inter-decadal variations, are discussed. The extreme complex and highly nonlinear nature of the monsoon-ENSO relationship is stressed. We find that for regional impacts on the monsoon, El Nino and La Nina are far from simply mirror images of each other. These two polarities of ENSO can have strong or no impacts on monsoon anomalies depending on the strength of the intraseasonal oscillations and the phases of the inter-decadal variations. For the Asian-Australian monsoon (AAM) as a whole, the ENSO impact is effected through a east-west shift in the Walker Circulation. For rainfall anomalies over specific monsoon areas, regional processes play important roles in addition to the shift in the Walker Circulation. One of the key regional processes identified for the boreal summer monsoon is the anomalous West Pacific Anticyclone (WPA). This regional feature has similar signatures in interannual and intraseasonal time scales and appears to determine whether the monsoon-ENSO relationship is strong or weak in a given year. Another important regional feature includes a rainfall and SST dipole across the Indian Ocean, which may have strong impact on the austral summer monsoon. Results are shown indicating that monsoon surface wind forcings may induce a strong biennial signal in ENSO and that strong monsoon-ENSO coupling may translate into pronounced biennial variability in ENSO. Finally, a new paradigm is proposed for the study of monsoon variability. This paradigm provides

  13. Workshop on Monsoon Climate Systems: Toward Better Prediction of the Monsoon

    SciTech Connect

    Sperber, K R; Yasunari, T

    2005-12-20

    The Earth's monsoon systems are the life-blood of more than two-thirds of the world's population through the rainfall they provide to the mainly agrarian societies they influence. More than 60 experts gathered to assess the current understanding of monsoon variability and to highlight outstanding problems simulating the monsoon.

  14. Toward a More Holistic Understanding of Filicide: A Multidisciplinary Analysis of 32 Years of U.S. Arrest Data

    PubMed Central

    Mariano, Timothy Y.; Chan, Heng Choon (Oliver); Myers, Wade C.

    2014-01-01

    Filicide is the killing one or more children by a parent, stepparent, or other parental figure. This study presents the first comprehensive analysis of U.S. filicide, drawn from 94,146 filicide arrests tabulated over a 32-year period in the U.S. Federal Bureau of Investigation’s Supplementary Homicide Reports (SHR). Filicides comprised 15% of all murders during this period. Modal victim age was less than one year old. One-third of victims were under a year old; over two-thirds were age six or less. Fathers were as likely as mothers to kill infants. The mean age of offenders was 32 years with a mode of 22 years, and nearly three-quarters were age 18 to 45. Female offenders were notably younger than their male counterparts. Black (or African American) offenders were significantly overrepresented in filicide compared to Whites. Most common killing methods included using hands and feet, strangulation, beating, asphyxiation, drowning, and defenestration. Stepparents were not at higher risk of filicide than genetic parents, but were twice as likely to kill using firearms. Synthesizing these results with studies from other fields, we propose three transdisciplinary, empirically-informed filicide categories primarily defined by effects of (1) psychopathology associated with neurotransmitter disturbances, (2) gender and sex hormones, and (3) evolutionary motives. Approaching filicide using this proposed hypothetical framework for future research may help identify at-risk populations and improve prevention and treatment. PMID:24529774

  15. Monsoon-extratropical circulation interactions in Himalayan extreme rainfall

    NASA Astrophysics Data System (ADS)

    Vellore, Ramesh K.; Kaplan, Michael L.; Krishnan, R.; Lewis, John M.; Sabade, Sudhir; Deshpande, Nayana; Singh, Bhupendra B.; Madhura, R. K.; Rama Rao, M. V. S.

    2016-06-01

    Extreme precipitation and flood episodes in the Himalayas are oftentimes traced to synoptic situations involving connections between equatorward advancing upper level extratropical circulations and moisture-laden tropical monsoon circulation. While previous studies have documented precipitation characteristics in the Himalayan region during severe storm cases, a comprehensive understanding of circulation dynamics of extreme precipitation mechanisms is still warranted. In this study, a detailed analysis is performed using rainfall observations and reanalysis circulation products to understand the evolution of monsoon-extratropical circulation features and their interactions based on 34 extreme precipitation events which occurred in the Western Himalayas (WEH) during the period 1979-2013. Our results provide evidence for a common large-scale circulation pattern connecting the extratropics and the South Asian monsoon region, which is favorable for extreme precipitation occurrences in the WEH region. This background upper level large-scale circulation pattern consists of a deep southward penetrating midlatitude westerly trough, a blocking high over western Eurasia and an intensifying Tibetan anticyclone. It is further seen from our analysis that the key elements of monsoon-midlatitude interactions, responsible for extreme precipitation events over the WEH region, are: (1) midlatitude Rossby wave breaking, (2) west-northwest propagation of monsoon low-pressure system from the Bay of Bengal across the Indian subcontinent, (3) eddy shedding of the Tibetan anticyclone, (4) ageostrophic motions and transverse circulation across the Himalayas, and (5) strong moist convection over the Himalayan foothills. Furthermore, high-resolution numerical simulations indicate that diabatic heating and mesoscale ageostrophic effects can additionally amplify the convective motions and precipitation in the WEH region.

  16. Spatiotemporal patterns and trends of Indian monsoonal rainfall extremes

    NASA Astrophysics Data System (ADS)

    Malik, Nishant; Bookhagen, Bodo; Mucha, Peter J.

    2016-02-01

    In this study, we provide a comprehensive analysis of trends in the extremes during the Indian summer monsoon (ISM) months (June to September) at different temporal and spatial scales. Our goal is to identify and quantify spatiotemporal patterns and trends that have emerged during the recent decades and may be associated with changing climatic conditions. Our analysis primarily relies on quantile regression that avoids making any subjective choices on spatial, temporal, or intensity pattern of extreme rainfall events. Our analysis divides the Indian monsoon region into climatic compartments that show different and partly opposing trends. These include strong trends toward intensified droughts in Northwest India, parts of Peninsular India, and Myanmar; in contrast, parts of Pakistan, Northwest Himalaya, and Central India show increased extreme daily rain intensity leading to higher flood vulnerability. Our analysis helps explain previously contradicting results of trends in average ISM rainfall.

  17. Spatiotemporal patterns and trends of Indian monsoonal rainfall extremes

    PubMed Central

    Malik, Nishant; Bookhagen, Bodo; Mucha, Peter J.

    2016-01-01

    In this study, we provide a comprehensive analysis of trends in the extremes during the Indian summer monsoon (ISM) months (June to September) at different temporal and spatial scales. Our goal is to identify and quantify spatiotemporal patterns and trends that have emerged during the recent decades and may be associated with changing climatic conditions. Our analysis primarily relies on quantile regression that avoids making any subjective choices on spatial, temporal, or intensity pattern of extreme rainfall events. Our analysis divides the Indian monsoon region into climatic compartments that show different and partly opposing trends. These include strong trends towards intensified droughts in Northwest India, parts of Peninsular India, and Myanmar; in contrast, parts of Pakistan, Northwest Himalaya, and Central India show increased extreme daily rain intensity leading to higher flood vulnerability. Our analysis helps explain previously contradicting results of trends in average ISM rainfall. PMID:27909349

  18. Breakfast: a multidisciplinary approach

    PubMed Central

    2013-01-01

    Background The role of breakfast as an essential part of an healthy diet has been only recently promoted even if breakfast practices were known since the Middle Age. The growing scientific evidences on this topic are extremely sector-based nevertheless breakfast could be regarded from different point of views and from different expertises. This approach, that take into account history, sociology, anthropology, medicine, psychology and pedagogy, is useful to better understand the value of this meal in our culture. The aim of this paper was to analyse breakfast-related issues based on a multidisciplinary approach with input by specialists from different fields of learning. Discussion Breakfast is now recommended as part of a diet because it is associated with healthier macro- and micronutrient intakes, body mass index and lifestyle. Moreover recent studies showed that breakfast improves cognitive function, intuitive perception and academic performance. Research demonstrates the importance of providing breakfast not only to children but in adults and elderly too. Although the important role breakfast plays in maintaining the health, epidemiological data from industrialised countries reveal that many individuals either eat a nutritionally unhealthy breakfast or skip it completely. Summary The historical, bio-psychological and educational value of breakfast in our culture is extremely important and should be recognized and stressed by the scientific community. Efforts should be done to promote this practice for the individual health and well-being. PMID:23842429

  19. Sub-seasonal Modulation of Indian Summer Monsoon Seasonal Predictability

    NASA Astrophysics Data System (ADS)

    Robertson, A. W.; Moron, V.; Pai, D. S.

    2015-12-01

    Recent studies have demonstrated that the Indian Summer Monsoon is more predictable during the early and late stages of the season, with a drop in rainfall predictability during the core monsoon months of July and August. Various theories have been advanced for this sub-seasonal evolution, but its origins are still poorly understood. We use a new 0.25-degree 1901-2014 daily rainfall dataset from the Indian Meteorological Department (IMD) to investigate this phenomenon at near-local scale, using more than a century of data. The analysis is based on daily rainfall characteristics, including the spatial coherence of sub-seasonal rainfall anomalies, and on relating these to large-scale moisture variables computed from reanalysis data. Indian summer monsoon rainfall is partitioned into three sub-seasonal phases, with a steep ramp-up (June), persistent core (July-August), and a slower decay phase (Sept-Oct). Spatial coherence of sub-seasonal rainfall anomalies is shown to be highest during the onset and decay phases with a marked mark drop during the core phase. Systematic shifts in seasonal timing are found to typify rainfall anomalies during the onset and decay phases, with ENSO preferentially impacting the latter. We identify a large-scale low-level moisture threshold as a necessary condition for local daily rainfall occuring at >5% of spatial locations across monsoonal India. Sub-seasonal rainfall variability during the onset and decay phases is argued to be controlled largely by the crossing of this threshold. However, this necessary condition is generally easily met during the core season, at which time interannual variability in low-level moisture and interannual correlation between rainfall and large-scale ascent both decrease. This decrease in large-scale control and the loss of spatial coherence imply that sub-seasonal to seasonal rainfall variations at local scales during the core of the monsoon are largely a result of local-scale processes, and are thus

  20. Monsoon rainfall interannual variability over China and its association with the Euasian circulation

    SciTech Connect

    Samel, A.N.; Wang, Wei-Chyung

    1997-11-01

    This study has two goals. The first is to determine annual observed initial and final dates of east Asian summer monsoon rainfall. To accomplish this, a semi-objective analysis is developed and applied to daily rainfall station data throughout China. The resulting values are used to calculate monsoon duration and total rainfall. The second goal is to identify relationships between these rainfall characteristics and circulation features in the Eurasian sea level pressure. The analysis of the duration of monsoon rainfall events produced results that are consistent with those found in previous studies. Total monsoon rainfall over south China, the Yangtze River valley, and north China was then correlated with the Eurasian sea level pressure and 500 millibar height fields. The results indicate that summer rainfall interannual variability over each region is governed by the interaction of several circulation features. These findings are also consistent with those of other studies. 18 refs., 5 figs.

  1. Aerosol and monsoon climate interactions over Asia

    NASA Astrophysics Data System (ADS)

    Li, Zhanqing; Lau, W. K.-M.; Ramanathan, V.; Wu, G.; Ding, Y.; Manoj, M. G.; Liu, J.; Qian, Y.; Li, J.; Zhou, T.; Fan, J.; Rosenfeld, D.; Ming, Y.; Wang, Y.; Huang, J.; Wang, B.; Xu, X.; Lee, S.-S.; Cribb, M.; Zhang, F.; Yang, X.; Zhao, C.; Takemura, T.; Wang, K.; Xia, X.; Yin, Y.; Zhang, H.; Guo, J.; Zhai, P. M.; Sugimoto, N.; Babu, S. S.; Brasseur, G. P.

    2016-12-01

    The increasing severity of droughts/floods and worsening air quality from increasing aerosols in Asia monsoon regions are the two gravest threats facing over 60% of the world population living in Asian monsoon regions. These dual threats have fueled a large body of research in the last decade on the roles of aerosols in impacting Asian monsoon weather and climate. This paper provides a comprehensive review of studies on Asian aerosols, monsoons, and their interactions. The Asian monsoon region is a primary source of emissions of diverse species of aerosols from both anthropogenic and natural origins. The distributions of aerosol loading are strongly influenced by distinct weather and climatic regimes, which are, in turn, modulated by aerosol effects. On a continental scale, aerosols reduce surface insolation and weaken the land-ocean thermal contrast, thus inhibiting the development of monsoons. Locally, aerosol radiative effects alter the thermodynamic stability and convective potential of the lower atmosphere leading to reduced temperatures, increased atmospheric stability, and weakened wind and atmospheric circulations. The atmospheric thermodynamic state, which determines the formation of clouds, convection, and precipitation, may also be altered by aerosols serving as cloud condensation nuclei or ice nuclei. Absorbing aerosols such as black carbon and desert dust in Asian monsoon regions may also induce dynamical feedback processes, leading to a strengthening of the early monsoon and affecting the subsequent evolution of the monsoon. Many mechanisms have been put forth regarding how aerosols modulate the amplitude, frequency, intensity, and phase of different monsoon climate variables. A wide range of theoretical, observational, and modeling findings on the Asian monsoon, aerosols, and their interactions are synthesized. A new paradigm is proposed on investigating aerosol-monsoon interactions, in which natural aerosols such as desert dust, black carbon from

  2. Dominating Controls for Wetter South Asian Summer Monsoon in the Twenty-First Century

    SciTech Connect

    Mei, Rui; Ashfaq, Moetasim; Rastogi, Deeksha; Leung, Lai-Yung R.; Dominguez, Francina

    2015-04-01

    We analyze a suite of Global Climate Models from the 5th Phase of Coupled Models Intercomparison Project (CMIP5) archives to understand the mechanisms behind a net increase in the South Asian summer monsoon precipitation in response to enhanced radiative forcing during the 21st century despite a robust weakening of dynamics governing the monsoon circulation. Combining the future changes in the contributions from various sources, which contribute to the moisture supply over South Asia, with those in monsoon dynamics and atmospheric moisture content, we establish a pathway of understanding that partly explains these counteracting responses to increase in radiative forcing. Our analysis suggests that both regional (local recycling, Arabian Sea, Bay of Bengal) and remote (mainly Indian Ocean) sources contribute to the moisture supply for precipitation over South Asia during the summer season that is facilitated by the monsoon dynamics. Increase in radiative forcing fuels an increase in the atmospheric moisture content through warmer temperatures. For regional moisture sources, the effect of excessive atmospheric moisture is offset by weaker monsoon circulation and uncertainty in the response of the evapotranspiration over land, so anomalies in their contribution to the total moisture supply are either mixed or muted. In contrast, weakening of the monsoon dynamics has less influence on the moisture supply from remote sources that not only is a dominant moisture contributor in the historical period, but is also the net driver of the positive summer monsoon precipitation response in the 21st century. Our results also indicate that historic measures of the monsoon dynamics may not be well suited to predict the non-stationary moisture driven South Asian summer monsoon precipitation response in the 21st century.

  3. Dominating Controls for Wetter South Asian Summer Monsoon in the Twenty-First Century

    DOE PAGES

    Mei, Rui; Ashfaq, Moetasim; Rastogi, Deeksha; ...

    2015-04-07

    This study analyzes a suite of global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) archives to understand the mechanisms behind a net increase in the South Asian summer monsoon precipitation in response to enhanced radiative forcing during the twenty-first century. An increase in radiative forcing fuels an increase in the atmospheric moisture content through warmer temperatures, which overwhelms the weakening of monsoon circulation and results in an increase of moisture convergence and therefore summer monsoon precipitation over South Asia. Moisture source analysis suggests that both regional (local recycling, the Arabian Sea, the Bay of Bengal)more » and remote (including the south Indian Ocean) sources contribute to the moisture supply for precipitation over South Asia during the summer season that is facilitated by the monsoon dynamics. For regional moisture sources, the effect of excessive atmospheric moisture is offset by weaker monsoon circulation and uncertainty in the response of the evapotranspiration over land, so anomalies in their contribution to the total moisture supply are either mixed or muted. In contrast, weakening of the monsoon dynamics has less influence on the moisture supply from remote sources that not only is a dominant moisture contributor in the historical period but is also the net driver of the positive summer monsoon precipitation response in the twenty-first century. Finally, the results also indicate that historic measures of the monsoon dynamics may not be well suited to predict the nonstationary moisture-driven South Asian summer monsoon precipitation response in the twenty-first century.« less

  4. Dominating Controls for Wetter South Asian Summer Monsoon in the Twenty-First Century

    SciTech Connect

    Mei, Rui; Ashfaq, Moetasim; Rastogi, Deeksha; Leung, L. Ruby; Dominguez, Francina

    2015-04-07

    This study analyzes a suite of global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) archives to understand the mechanisms behind a net increase in the South Asian summer monsoon precipitation in response to enhanced radiative forcing during the twenty-first century. An increase in radiative forcing fuels an increase in the atmospheric moisture content through warmer temperatures, which overwhelms the weakening of monsoon circulation and results in an increase of moisture convergence and therefore summer monsoon precipitation over South Asia. Moisture source analysis suggests that both regional (local recycling, the Arabian Sea, the Bay of Bengal) and remote (including the south Indian Ocean) sources contribute to the moisture supply for precipitation over South Asia during the summer season that is facilitated by the monsoon dynamics. For regional moisture sources, the effect of excessive atmospheric moisture is offset by weaker monsoon circulation and uncertainty in the response of the evapotranspiration over land, so anomalies in their contribution to the total moisture supply are either mixed or muted. In contrast, weakening of the monsoon dynamics has less influence on the moisture supply from remote sources that not only is a dominant moisture contributor in the historical period but is also the net driver of the positive summer monsoon precipitation response in the twenty-first century. Finally, the results also indicate that historic measures of the monsoon dynamics may not be well suited to predict the nonstationary moisture-driven South Asian summer monsoon precipitation response in the twenty-first century.

  5. Simulation of the northern summer monsoon in the ECMWF model: Sensitivity to horizontal resolution

    SciTech Connect

    Sperber, K.R.; Potter, G.L.; Boyle, J.S.; Hameed, S.

    1994-11-01

    The ability of the ECMWF model (cycle 33) to simulate the Indian and East Asian summer monsoons is evaluated at four different horizontal resolutions: T21, T42, T63, and T106. Generally, with respect to the large-scale features of the circulation, the largest differences among the simulations occur at T42 relative to T21. However, on regional scales, important differences among the high-frequency temporal variability serve as a further critical test of the model`s ability to simulate the monsoon. T106 best captures both the spatial and temporal characteristics of the Indian and East Asian monsoons, whereas T42 fails to correctly simulate the sequence and development of synoptic-scale milestones that characterize the monsoon flow. In particular, T106 is superior at simulating the development and migration of the monsoon trough over the Bay of Bengal. In the T42 simulation, the development of the monsoon occurs one month earlier than typically observed. At this time the trough is incorrectly located adjacent to the east coast of India, which results in an underestimate of precipitation over the Burma-Thailand region. This early establishment of the monsoon trough affects the evolution of the East Asian monsoon and yields excessive preseason rainfall over the Mei-yu-region. EOF analysis of precipitation over China indicates that T106 best simulates the Mei-yu mode of variability, which is associated with an oscillation of the rainband that gives rise to periods of Mei-yu mode of variability, which is associated with an oscillation of the rainband that gives rise to periods of enhanced rainfall over the Yangtze River valley. The coarse resolution of T21 precludes simulation of the aforementioned regional-scale monsoon flows. 43 refs., 14 figs.

  6. Sea surface height anomaly and upper ocean temperature over the Indian Ocean during contrasting monsoons

    NASA Astrophysics Data System (ADS)

    Gera, Anitha; Mitra, A. K.; Mahapatra, D. K.; Momin, I. M.; Rajagopal, E. N.; Basu, Swati

    2016-09-01

    Recent research emphasizes the importance of the oceanic feedback to monsoon rainfall over the Asian landmass. In this study, we investigate the differences in the sea surface height anomaly (SSHA) and upper ocean temperature over the tropical Indian Ocean during multiple strong and weak monsoons. Analysis of satellite derived SSHA, sea surface temperature (SST) and ocean reanalysis data reveals that patterns of SSHA, SST, ocean temperature, upper ocean heat content (UOHC) and propagations of Kelvin and Rossby waves differ during strong and weak monsoon years. During strong monsoons positive SSH, SST and UOHC anomalies develop over large parts of north Indian Ocean whereas during weak monsoons much of the north Indian Ocean is covered with negative anomalies. These patterns can be used as a standard tool for evaluating the performance of coupled and ocean models in simulating & forecasting strong and weak monsoons. The rainfall over central India is found to be significantly correlated with SSHA over the regions (Arabian Sea and West central Indian Ocean and Bay of Bengal) where SSHA is positively large during strong monsoons. The SST-SSHA correlation is also very strong over the same area. The study reveals that much convection takes place over these regions during strong monsoons. In contrast during weak monsoons, convection takes place over eastern equatorial region. These changes in SST are largely influenced by oceanic Kelvin and Rossby waves. The Rossby waves initiated in spring at the eastern boundary propagate sub-surface heat content in the ocean influencing SST in summer. The SST anomalies modulate the Hadley circulation and the moisture transport thereby contributing to rainfall over central India. Therefore oceanic Kelvin and Rossby waves influence the rainfall over central India.

  7. Thermal controls on the Asian summer monsoon.

    PubMed

    Wu, Guoxiong; Liu, Yimin; He, Bian; Bao, Qing; Duan, Anmin; Jin, Fei-Fei

    2012-01-01

    The Asian summer monsoon affects more than sixty percent of the world's population; understanding its controlling factors is becoming increasingly important due to the expanding human influence on the environment and climate and the need to adapt to global climate change. Various mechanisms have been suggested; however, an overarching paradigm delineating the dominant factors for its generation and strength remains debated. Here we use observation data and numerical experiments to demonstrates that the Asian summer monsoon systems are controlled mainly by thermal forcing whereas large-scale orographically mechanical forcing is not essential: the South Asian monsoon south of 20°N by land-sea thermal contrast, its northern part by the thermal forcing of the Iranian Plateau, and the East Asian monsoon and the eastern part of the South Asian monsoon by the thermal forcing of the Tibetan Plateau.

  8. Multidisciplinary tailoring of hot composite structures

    NASA Technical Reports Server (NTRS)

    Singhal, Surendra N.; Chamis, Christos C.

    1993-01-01

    A computational simulation procedure is described for multidisciplinary analysis and tailoring of layered multi-material hot composite engine structural components subjected to simultaneous multiple discipline-specific thermal, structural, vibration, and acoustic loads. The effect of aggressive environments is also simulated. The simulation is based on a three-dimensional finite element analysis technique in conjunction with structural mechanics codes, thermal/acoustic analysis methods, and tailoring procedures. The integrated multidisciplinary simulation procedure is general-purpose including the coupled effects of nonlinearities in structure geometry, material, loading, and environmental complexities. The composite material behavior is assessed at all composite scales, i.e., laminate/ply/constituents (fiber/matrix), via a nonlinear material characterization hygro-thermo-mechanical model. Sample tailoring cases exhibiting nonlinear material/loading/environmental behavior of aircraft engine fan blades, are presented. The various multidisciplinary loads lead to different tailored designs, even those competing with each other, as in the case of minimum material cost versus minimum structure weight and in the case of minimum vibration frequency versus minimum acoustic noise.

  9. Multidisciplinary tailoring of hot composite structures

    NASA Technical Reports Server (NTRS)

    Singhal, Surendra N.; Chamis, Christos C.

    1992-01-01

    A computational simulation procedure is described for multidisciplinary analysis and tailoring of multilayered multimaterial hot composite engine structural components subjected to simultaneous multiple discipline-specific thermal, structural, vibration, and acoustic loadings including the effect of aggressive environments. The simulation is based on a 3D finite element analysis technique in conjunction with structural mechanics codes, thermal/acoustic analysis methods, and tailoring procedures. The integrated multidisciplinary simulation procedure is general-purpose including the coupled effects of nonlinearities in structure geometry, material, loading, and environmental complexities. The composite material behavior is assessed at all composite scales, i.e., the laminate/ply/constituents (fiber/matrix), via a nonlinear material characterization hygro-thermomechanical model. Sample tailoring cases exhibiting nonlinear material/loading/environmental behavior of aircraft engine fan blades, are presented. The various multidisciplinary loadings lead to different tailored designs, even those opposite of each other, as in the case of minimum material cost versus minimum structure weight and in the case of minimum vibration frequency versus minimum acoustic noise.

  10. Toward continuous quantification of lava extrusion rate: Results from the multidisciplinary analysis of the 2 January 2010 eruption of Piton de la Fournaise volcano, La Réunion.

    NASA Astrophysics Data System (ADS)

    Hibert, Clement; Mangeney, Anne; Polacci, Margherita; Di Muro, Andrea; Vergniolle, Sylvie; Ferrazzini, Valérie; Peltier, Aline; Taisne, Benoit; Burton, Mike; Dewez, Thomas; Grandjean, Gilles; Dupont, Aurélien; Staudacher, Thomas; Brenguier, Florent; Kowalski, Philippe; Boissier, Patrice; Catherine, Philippe; Lauret, Frédéric

    2016-04-01

    The dynamics of the 2-12 January 2010 effusive eruption at Piton de la Fournaise volcano were examined through seismic and infrasound records, time-lapse photography, SO2 flux measurements, deformation data, and direct observations. Digital elevation models were constructed for four periods of the eruption, thus providing an assessment of the temporal evolution of the morphology, the volume and the extrusion rate of the lava flow. These data were compared to the continuous recording of the seismic and infrasonic waves, and a linear relationship was found between the seismic energy of the tremor and the lava extrusion rate. This relationship is supported by data from three other summit eruptions of Piton de la Fournaise and gives total volume and average lava extrusion rate in good agreement with previous studies. We can therefore provide an estimate of the lava extrusion rate for the January 2010 eruption with a very high temporal resolution. We found an average lava extrusion rate of 2.4 m3.s-1 with a peak of 106.6 m3.s-1 during the initial lava fountaining phase. We use the inferred average lava extrusion rate during the lava fountaining phase (30.23 m3.s-1) to estimate the value of the initial overpressure in the magma reservoir, which we found to range from 3.7×106 Pa to 5.9×106 Pa. Finally, based on the estimated initial overpressure, the volume of magma expelled during the lava fountaining phase and geodetic data, we inferred the volume of the magma reservoir using a simple Mogi model, between 0.25 km3 and 0.54 km3, which is in good agreement with previous studies. The multidisciplinary analysis presented in our study sheds light on crucial qualitative and quantitative relations between eruption dynamics, seismic and infrasonic signals, and especially on the direct link between the lava extrusion rate and the seismic energy of the volcanic tremor. If this relationship is confirmed for other eruptions, generalization of its use will lead to a better

  11. Barriers and Challenges in Seeking Psychiatric Intervention in a General Hospital, by the Collaborative Child Response Unit, (A Multidisciplinary Team Approach to Handling Child Abuse) A Qualitative Analysis.

    PubMed

    Subramaniyan, Vyjayanthi Kanugodu Srinivasa; Mital, Anukant; Rao, Chandrika; Chandra, Girish

    2017-01-01

    Child abuse is a serious criminal act against children in our country and punishable according to protection of children from sexual offenses act 2012. No one agency has the ability to respond completely to the abuse. Hence a multidisciplinary team approach was developed in India. Aim is to narrate the collaborative effort among the multiple disciplines in a general hospital to deliver child protection services and explore the barriers to integrate psychiatric services.

  12. An Overview of Three Approaches to Multidisciplinary Aeropropulsion Simulations

    NASA Technical Reports Server (NTRS)

    Lawrence, Charles

    1997-01-01

    The broad scope of aeropropulsion multidisciplinary applications necessitates that a collection of approaches, with distinct capabilities, be developed. Three general approaches to multidisciplinary simulations have been identified. The three approaches; loosely coupled, coupled process, and multiphysics, provide a comprehensive collection of capabilities for multidisciplinary aeropropulsion analysis. At the data access level, or loosely coupled approach of coupling, existing disciplinary simulations are run, data is generated, and made available and used for subsequent analysis. The data must be in the correct format for implementation by the subsequent analysis but the subsequent code need not directly communicate with the previous code. At the process level, or coupled process approach of coupling, individual disciplinary codes are used, similarly to the loosely coupled approach, however, in the coupled process approach the disciplinary codes need to run concurrently with each other. The system of equation coupled approach, or multiphysics approach, addresses those applications whose characteristics require that the disciplines be coupled at the fundamental equation level to accurately, or more efficiently, capture the multidisciplinary physics of the problem. No one of these approaches, by itself, addresses all of the community needs in this area. However, collectively the three approaches encompass all of the multidisciplinary applications which have been identified thus far. Multiple approaches to multidisciplinary simulations will be needed as long as the applications and their requirements remain as diverse as they currently are today.

  13. An assessment of Indian monsoon seasonal forecasts and mechanisms underlying monsoon interannual variability in the Met Office GloSea5-GC2 system

    NASA Astrophysics Data System (ADS)

    Johnson, Stephanie J.; Turner, Andrew; Woolnough, Steven; Martin, Gill; MacLachlan, Craig

    2017-03-01

    We assess Indian summer monsoon seasonal forecasts in GloSea5-GC2, the Met Office fully coupled subseasonal to seasonal ensemble forecasting system. Using several metrics, GloSea5-GC2 shows similar skill to other state-of-the-art seasonal forecast systems. The prediction skill of the large-scale South Asian monsoon circulation is higher than that of Indian monsoon rainfall. Using multiple linear regression analysis we evaluate relationships between Indian monsoon rainfall and five possible drivers of monsoon interannual variability. Over the time period studied (1992-2011), the El Niño-Southern Oscillation (ENSO) and the Indian Ocean dipole (IOD) are the most important of these drivers in both observations and GloSea5-GC2. Our analysis indicates that ENSO and its teleconnection with Indian rainfall are well represented in GloSea5-GC2. However, the relationship between the IOD and Indian rainfall anomalies is too weak in GloSea5-GC2, which may be limiting the prediction skill of the local monsoon circulation and Indian rainfall. We show that this weak relationship likely results from a coupled mean state bias that limits the impact of anomalous wind forcing on SST variability, resulting in erroneous IOD SST anomalies. Known difficulties in representing convective precipitation over India may also play a role. Since Indian rainfall responds weakly to the IOD, it responds more consistently to ENSO than in observations. Our assessment identifies specific coupled biases that are likely limiting GloSea5-GC2 Indian summer monsoon seasonal prediction skill, providing targets for model improvement.

  14. Fingerprinting the Impacts of Aerosols on Long-Term Trends of the Indian Summer Monsoon Regional Rainfall

    NASA Technical Reports Server (NTRS)

    Laul, K. M.; Kim, K. M.

    2010-01-01

    In this paper, we present corroborative observational evidences from satellites, in-situ observations, and re-analysis data showing possible impacts of absorbing aerosols (black carbon and dust) on subseasonal and regional summer monsoon rainfall over India. We find that increased absorbing aerosols in the Indo-Gangetic Plain in recent decades may have lead to long-term warming of the upper troposphere over northern India and the Tibetan Plateau, enhanced rainfall in northern India and the Himalayas foothill regions in the early part (may-June) of the monsoon season, followed by diminished rainfall over central and southern India in the latter part (July-August) of the monsoon season. These signals which are consistent with current theories of atmospheric heating and solar dimming by aerosol and induced cloudiness in modulating the Indian monsoon, would have been masked by conventional method of using al-India rainfall averaged over the entire monsoon season.

  15. Numerical prediction of the monsoon depression of 5-7 July 1979. [Monsoon Experiment (MONEX)

    NASA Technical Reports Server (NTRS)

    Shukla, J.; Atlas, R.; Baker, W. E.

    1981-01-01

    A well defined monsoon depression was used for two assimilation and forecast experiments: (1) using conventional surface and upper air data, (2) using these data plus Monex data. The data sets were assimilated and used with a general circulation model to make numerical predictions. The model, the analysis and assimilation procedure, the differences in the analyses due to different data inputs, and the differences in the numerical predictions are described. The MONEX data have a positive impact, although the differences after 24 hr are not significant. The MONEX assimilation does not agree with manual analysis location of depression center. The 2.5 x 3 deg horizontal resolution of the prediction model is too coarse. The assimilation of geopotential height data derived from satellite soundings generated gravity waves with amplitudes similar to the meteorologically significant features investigated.

  16. The East Asian subtropical summer monsoon: Recent progress

    NASA Astrophysics Data System (ADS)

    He, Jinhai; Liu, Boqi

    2016-04-01

    The East Asian subtropical summer monsoon (EASSM) is one component of the East Asian summer monsoon system, and its evolution determines the weather and climate over East China. In the present paper, we firstly demonstrate the formation and advancement of the EASSM rainbelt and its associated circulation and precipitation patterns through reviewing recent studies and our own analysis based on JRA-55 (Japanese 55-yr Reanalysis) data and CMAP (CPC Merged Analysis of Precipitation), GPCP (Global Precipitation Climatology Project), and TRMM (Tropical Rainfall Measuring Mission) precipitation data. The results show that the rainy season of the EASSM starts over the region to the south of the Yangtze River in early April, with the establishment of strong southerly wind in situ. The EASSM rainfall, which is composed of dominant convective and minor stratiform precipitation, is always accompanied by a frontal system and separated from the tropical summer monsoon system. It moves northward following the onset of the South China Sea summer monsoon. Moreover, the role of the land-sea thermal contrast in the formation and maintenance of the EASSM is illustrated, including in particular the effect of the seasonal transition of the zonal land-sea thermal contrast and the influences from the Tibetan Plateau and midlatitudes. In addition, we reveal a possible reason for the subtropical climate difference between East Asia and East America. Finally, the multi-scale variability of the EASSM and its influential factors are summarized to uncover possible reasons for the intraseasonal, interannual, and interdecadal variability of the EASSM and their importance in climate prediction.

  17. GMMIP (v1.0) contribution to CMIP6: Global Monsoons Model Inter-comparison Project

    SciTech Connect

    Zhou, Tianjun; Turner, Andrew G.; Kinter, James L.; Wang, Bin; Qian, Yun; Chen, Xiaolong; Wu, Bo; Wang, Bin; Liu, Bo; Zou, Liwei; He, Bian

    2016-10-10

    The Global Monsoons Model Inter-comparison Project (GMMIP) has been endorsed by the panel of Coupled Model Inter-comparison Project (CMIP) as one of the participating model inter-comparison projects (MIPs) in the sixth phase of CMIP (CMIP6). The focus of GMMIP is on monsoon climatology, variability, prediction and projection, which is relevant to four of the “Grand Challenges” proposed by the World Climate Research Programme. At present, 21 international modeling groups are committed to joining GMMIP. This overview paper introduces the motivation behind GMMIP and the scientific questions it intends to answer. Three tiers of experiments, of decreasing priority, are designed to examine (a) model skill in simulating the climatology and interannual-to-multidecadal variability of global monsoons forced by the sea surface temperature during historical climate period; (b) the roles of the Interdecadal Pacific Oscillation and Atlantic Multidecadal Oscillation in driving variations of the global and regional monsoons; and (c) the effects of large orographic terrain on the establishment of the monsoons. The outputs of the CMIP6 Diagnostic, Evaluation and Characterization of Klima experiments (DECK), “historical” simulation and endorsed MIPs will also be used in the diagnostic analysis of GMMIP to give a comprehensive understanding of the roles played by different external forcings, potential improvements in the simulation of monsoon rainfall at high resolution and reproducibility at decadal timescales. The implementation of GMMIP will improve our understanding of the fundamental physics of changes in the global and regional monsoons over the past 140 years and ultimately benefit monsoons prediction and projection in the current century.

  18. GMMIP (v1.0) contribution to CMIP6: Global Monsoons Model Inter-comparison Project

    NASA Astrophysics Data System (ADS)

    Zhou, Tianjun; Turner, Andrew G.; Kinter, James L.; Wang, Bin; Qian, Yun; Chen, Xiaolong; Wu, Bo; Wang, Bin; Liu, Bo; Zou, Liwei; He, Bian

    2016-10-01

    The Global Monsoons Model Inter-comparison Project (GMMIP) has been endorsed by the panel of Coupled Model Inter-comparison Project (CMIP) as one of the participating model inter-comparison projects (MIPs) in the sixth phase of CMIP (CMIP6). The focus of GMMIP is on monsoon climatology, variability, prediction and projection, which is relevant to four of the "Grand Challenges" proposed by the World Climate Research Programme. At present, 21 international modeling groups are committed to joining GMMIP. This overview paper introduces the motivation behind GMMIP and the scientific questions it intends to answer. Three tiers of experiments, of decreasing priority, are designed to examine (a) model skill in simulating the climatology and interannual-to-multidecadal variability of global monsoons forced by the sea surface temperature during historical climate period; (b) the roles of the Interdecadal Pacific Oscillation and Atlantic Multidecadal Oscillation in driving variations of the global and regional monsoons; and (c) the effects of large orographic terrain on the establishment of the monsoons. The outputs of the CMIP6 Diagnostic, Evaluation and Characterization of Klima experiments (DECK), "historical" simulation and endorsed MIPs will also be used in the diagnostic analysis of GMMIP to give a comprehensive understanding of the roles played by different external forcings, potential improvements in the simulation of monsoon rainfall at high resolution and reproducibility at decadal timescales. The implementation of GMMIP will improve our understanding of the fundamental physics of changes in the global and regional monsoons over the past 140 years and ultimately benefit monsoons prediction and projection in the current century.

  19. Hydrologic Processes Associated with the First Transition of the Asian Summer Monsoon: A TRMM Pilot Study

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.

    1998-01-01

    We present results of a pilot study of the evolution of large scale hydrologic processes associated with the first transition of the Asian summer monsoon in conjunction with the launching of the South China Sea Monsoon Experiment (SCSMEX) in May, 1998. Using a combination of satellite-estimated rainfall, moisture, surface wind and sea surface temperature, we present some interesting and hitherto unknown features in large scale atmospheric and oceanic hydrologic processes associated with the fluctuation of the SCS monsoon. Results show that, climatologically, the SCS monsoon occurs during mid-May when major convection zone shifts from the eastern Indian Ocean/southern Indochina to the SCS. Simultaneously with the SCS monsoon onset is the development of a moist tongue and frontal rainband emanating from northern SCS, across southern China and the East China Sea to southern Japan as well as the enhancement of equatorial convection in the western Pacific ITCZ. Analysis of the satellite-derived moisture and rainfall show that the onset of the SCS monsoon during 1997 was preceded by the development of eastward propagating supercloud clusters over the Indian Ocean. The satellite data also reveal a strong onset vortex over the SCS and large scale cooling and warming patterns over the Indian Ocean and western Pacific. These features signal a major shift of the large-scale hydrologic cycle in the ocean-atmosphere system, which underpins the SCS monsoon onset. The paper concludes with a brief discussion of the observational platform of SCSMEX and a call for the utility of satellite data, field observations and models for comprehensive studies of the Asian monsoon.

  20. Multidisciplinary Management of Pituitary Apoplexy

    PubMed Central

    Albani, Adriana; Angileri, Filippo Flavio; Esposito, Felice; Granata, Francesca; Ferreri, Felicia; Cannavò, Salvatore

    2016-01-01

    Pituitary apoplexy is a rare clinical syndrome due to ischemic or haemorrhagic necrosis of the pituitary gland which complicates 2–12% of pituitary tumours, especially nonfunctioning adenomas. In many cases, it results in severe neurological, ophthalmological, and endocrinological consequences and may require prompt surgical decompression. Pituitary apoplexy represents a rare medical emergency that necessitates a multidisciplinary approach. Modalities of treatment and times of intervention are still largely debated. Therefore, the management of patients with pituitary apoplexy is often empirically individualized and clinical outcome is inevitably related to the multidisciplinary team's skills and experience. This review aims to highlight the importance of a multidisciplinary approach in the management of pituitary apoplexy and to discuss modalities of presentation, treatment, and times of intervention. PMID:28074095

  1. Sensible and latent heat forced divergent circulations in the West African Monsoon System

    NASA Astrophysics Data System (ADS)

    Hagos, S.; Zhang, C.

    2008-12-01

    Field properties of divergent circulation are utilized to identify the roles of various diabatic processes in forcing moisture transport in the dynamics of the West African Monsoon and its seasonal cycle. In this analysis, the divergence field is treated as a set of point sources and is partitioned into two sub-sets corresponding to latent heat release and surface sensible heat flux at each respective point. The divergent circulation associated with each set is then calculated from the Poisson's equation using Gauss-Seidel iteration. Moisture transport by each set of divergent circulation is subsequently estimated. The results show different roles of the divergent circulations forced by surface sensible and latent heating in the monsoon dynamics. Surface sensible heating drives a shallow meridional circulation, which transports moisture deep into the continent at the polar side of the monsoon rain band and thereby promotes the seasonal northward migration of monsoon precipitation during the monsoon onset season. In contrast, the circulation directly associated with latent heating is deep and the corresponding moisture convergence is within the region of precipitation. Latent heating also induces dry air advection from the north. Neither effect promotes the seasonal northward migration of precipitation. The relative contributions of the processes associated with latent and sensible heating to the net moisture convergence, and hence the seasonal evolution of monsoon precipitation, depend on the background moisture.

  2. Mid-Holocene global monsoon area and precipitation from PMIP simulations

    NASA Astrophysics Data System (ADS)

    Jiang, Dabang; Tian, Zhiping; Lang, Xianmei

    2015-05-01

    Towards a better insight into orbital-scale changes in global monsoon, here we examine global monsoon area (GMA) and precipitation (GMP) as well as GMP intensity (GMPI) in the mid-Holocene, approximately 6,000 years ago, using all available numerical experiments from the Paleoclimate Modelling Intercomparison Project. Compared to the reference period, both the mid-Holocene GMA and GMP increased in the majority of the 35 models chosen for analysis according to their ability, averaging 5.5 and 4.2 %, respectively, which were mainly due to the increase in monsoon area and precipitation over the boreal land and austral ocean. The mid-Holocene GMPI decreased in most models and by an average of 1.2 %, mainly due to the decrease in monsoon precipitation intensity over the boreal ocean and austral land. The mid-Holocene GMA, GMP, and GMPI all showed opposite changes both between the land and ocean in the northern or southern hemisphere and between the boreal and austral land or ocean. Orbital-induced changes in large-scale meridional temperature gradient and land-sea thermal contrast are the underlying mechanisms, and the presence of an interactive ocean has an amplifying effect in the boreal land monsoon areas overall. Qualitatively, the model-data comparison indicates agreement in the boreal land monsoon areas and South America but disagreement in southern Africa and northern Australia.

  3. On the decreasing trend of the number of monsoon depressions in the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Vishnu, S.; Francis, P. A.; Shenoi, S. S. C.; Ramakrishna, S. S. V. S.

    2016-01-01

    This study unravels the physical link between the weakening of the monsoon circulation and the decreasing trend in the frequency of monsoon depressions over the Bay of Bengal. Based on the analysis of the terms of Genesis Potential Index, an empirical index to quantify the relative contribution of large scale environmental variables responsible for the modulation of storms, it is shown here that the reduction in the mid-tropospheric relative humidity is the most important reason for the decrease in the number of monsoon depressions. The net reduction of relative humidity over the Bay of Bengal is primarily due to the decrease in the moisture flux convergence, which is attributed to the weakening of the low level jet, a characteristic feature of monsoon circulation. Further, the anomalous moisture convergence over the western equatorial Indian Ocean associated with the rapid warming of the sea surface, reduces the moisture advection into the Bay of Bengal and hence adversely affect the genesis/intensification of monsoon depressions. Hence, the reduction in the number of monsoon depression over the Bay of Bengal could be one of the manifestations of the differential rates in the observed warming trend of the Indian Ocean basin.

  4. Multidisciplinary design optimization using multiobjective formulation techniques

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Aditi; Pagaldipti, Narayanan S.

    1995-01-01

    This report addresses the development of a multidisciplinary optimization procedure using an efficient semi-analytical sensitivity analysis technique and multilevel decomposition for the design of aerospace vehicles. A semi-analytical sensitivity analysis procedure is developed for calculating computational grid sensitivities and aerodynamic design sensitivities. Accuracy and efficiency of the sensitivity analysis procedure is established through comparison of the results with those obtained using a finite difference technique. The developed sensitivity analysis technique are then used within a multidisciplinary optimization procedure for designing aerospace vehicles. The optimization problem, with the integration of aerodynamics and structures, is decomposed into two levels. Optimization is performed for improved aerodynamic performance at the first level and improved structural performance at the second level. Aerodynamic analysis is performed by solving the three-dimensional parabolized Navier Stokes equations. A nonlinear programming technique and an approximate analysis procedure are used for optimization. The proceduredeveloped is applied to design the wing of a high speed aircraft. Results obtained show significant improvements in the aircraft aerodynamic and structural performance when compared to a reference or baseline configuration. The use of the semi-analytical sensitivity technique provides significant computational savings.

  5. The spectrum of Asian monsoon variability

    NASA Astrophysics Data System (ADS)

    Loope, G. R.; Overpeck, J. T.

    2014-12-01

    The Indian monsoon is the critical source of freshwater for over one billion people. Variability in monsoon precipitation occurs on all time scales and has severe consequences for the people who depend on monsoon rains. Extreme precipitation events have increased in the 20th century and are predicted to continue to become more frequent with anthropogenic global warming. The most recent models project that both monsoon precipitation and variability of precipitation will increase over the 21st century leading to increased flooding and possibly severe droughts. Although current models are able to capture the risk of relatively short droughts (1-5 years) reasonably well, they tend to underestimate the risk of longer, decadal- multidecadal droughts. I use observational records over the last 100 years in conjunction with cave, tree ring, and lake data from the NOAA paleoclimate database to reconstruct Holocene monsoon variability. I am able to show that the Asian monsoon has more low frequency variability than is projected by current climate models. The growing evidence for this discrepancy in hydroclimate variability between models and observational/paleoclimate records is of grave concern. If these models fail to capture the decadal-multidecadal droughts of the past it is likely they will underestimate the possibility of such droughts in the future.

  6. Basic mechanism for abrupt monsoon transitions

    PubMed Central

    Levermann, Anders; Schewe, Jacob; Petoukhov, Vladimir; Held, Hermann

    2009-01-01

    Monsoon systems influence the livelihood of hundreds of millions of people. During the Holocene and last glacial period, rainfall in India and China has undergone strong and abrupt changes. Though details of monsoon circulations are complicated, observations reveal a defining moisture-advection feedback that dominates the seasonal heat balance and might act as an internal amplifier, leading to abrupt changes in response to relatively weak external perturbations. Here we present a minimal conceptual model capturing this positive feedback. The basic equations, motivated by observed relations, yield a threshold behavior, robust with respect to addition of other physical processes. Below this threshold in net radiative influx, R c, no conventional monsoon can develop; above R c, two stable regimes exist. We identify a nondimensional parameter l that defines the threshold and makes monsoon systems comparable with respect to the character of their abrupt transition. This dynamic similitude may be helpful in understanding past and future variations in monsoon circulation. Within the restrictions of the model, we compute R c for current monsoon systems in India, China, the Bay of Bengal, West Africa, North America, and Australia, where moisture advection is the main driver of the circulation. PMID:19858472

  7. Basic mechanism for abrupt monsoon transitions.

    PubMed

    Levermann, Anders; Schewe, Jacob; Petoukhov, Vladimir; Held, Hermann

    2009-12-08

    Monsoon systems influence the livelihood of hundreds of millions of people. During the Holocene and last glacial period, rainfall in India and China has undergone strong and abrupt changes. Though details of monsoon circulations are complicated, observations reveal a defining moisture-advection feedback that dominates the seasonal heat balance and might act as an internal amplifier, leading to abrupt changes in response to relatively weak external perturbations. Here we present a minimal conceptual model capturing this positive feedback. The basic equations, motivated by observed relations, yield a threshold behavior, robust with respect to addition of other physical processes. Below this threshold in net radiative influx, R(c), no conventional monsoon can develop; above R(c), two stable regimes exist. We identify a nondimensional parameter l that defines the threshold and makes monsoon systems comparable with respect to the character of their abrupt transition. This dynamic similitude may be helpful in understanding past and future variations in monsoon circulation. Within the restrictions of the model, we compute R(c) for current monsoon systems in India, China, the Bay of Bengal, West Africa, North America, and Australia, where moisture advection is the main driver of the circulation.

  8. Potential Predictability of the Monsoon Subclimate Systems

    NASA Technical Reports Server (NTRS)

    Yang, Song; Lau, K.-M.; Chang, Y.; Schubert, S.

    1999-01-01

    While El Nino/Southern Oscillation (ENSO) phenomenon can be predicted with some success using coupled oceanic-atmospheric models, the skill of predicting the tropical monsoons is low regardless of the methods applied. The low skill of monsoon prediction may be either because the monsoons are not defined appropriately or because they are not influenced significantly by boundary forcing. The latter characterizes the importance of internal dynamics in monsoon variability and leads to many eminent chaotic features of the monsoons. In this study, we analyze results from nine AMIP-type ensemble experiments with the NASA/GEOS-2 general circulation model to assess the potential predictability of the tropical climate system. We will focus on the variability and predictability of tropical monsoon rainfall on seasonal-to-interannual time scales. It is known that the tropical climate is more predictable than its extratropical counterpart. However, predictability is different from one climate subsystem to another within the tropics. It is important to understand the differences among these subsystems in order to increase our skill of seasonal-to-interannual prediction. We assess potential predictability by comparing the magnitude of internal and forced variances as defined by Harzallah and Sadourny (1995). The internal variance measures the spread among the various ensemble members. The forced part of rainfall variance is determined by the magnitude of the ensemble mean rainfall anomaly and by the degree of consistency of the results from the various experiments.

  9. Aerosol and monsoon climate interactions over Asia: AEROSOL AND MONSOON CLIMATE INTERACTIONS

    SciTech Connect

    Li, Zhanqing; Lau, W. K. -M.; Ramanathan, V.; Wu, G.; Ding, Y.; Manoj, M. G.; Liu, J.; Qian, Y.; Li, J.; Zhou, T.; Fan, J.; Rosenfeld, D.; Ming, Y.; Wang, Y.; Huang, J.; Wang, B.; Xu, X.; Lee, S. -S.; Cribb, M.; Zhang, F.; Yang, X.; Zhao, C.; Takemura, T.; Wang, K.; Xia, X.; Yin, Y.; Zhang, H.; Guo, J.; Zhai, P. M.; Sugimoto, N.; Babu, S. S.; Brasseur, G. P.

    2016-11-15

    Asian monsoons and aerosols have been studied extensively which are intertwined in influencing the climate of Asia. This paper provides a comprehensive review of ample studies on Asian aerosol, monsoon and their interactions. The region is the primary source of aerosol emissions of varies species, influenced by distinct weather and climatic regimes. On continental scale, aerosols reduce surface insolation and weaken the land-ocean thermal contrast, thus inhibiting the development of monsoons. Locally, aerosol radiative effects alter the thermodynamic stability and convective potential of the lower atmosphere leading to reduced temperatures, increased atmospheric stability, and weakened wind and atmospheric circulation. The atmospheric thermodynamic state may also be altered by the aerosol serving as cloud condensation nuclei or ice nuclei. Many mechanisms have been put forth regarding how aerosols modulate the amplitude, frequency, intensity, and phase of numerous monsoon climate variables. A wide range of theoretical, observational, and modeling findings on the Asian monsoon, aerosols, and their interactions are synthesized. A new paradigm is proposed on investigating aerosol-monsoon interactions, in which natural aerosols such as desert dust, black carbon from biomass burning, and biogenic aerosols from vegetation are considered integral components of an intrinsic aerosol-monsoon climate system, subject to external forcings of global warming, anthropogenic aerosols, and land use and change. Future research on aerosol-monsoon interactions calls for an integrated approach and international collaborations based on long-term sustained observations, process measurements, and improved models, as well as using observations to constrain model simulations and projections.

  10. Giant Serpentine Aneurysms: Multidisciplinary Management

    PubMed Central

    Anshun, W.; Feng, L.; Daming, W.

    2000-01-01

    Summary Sixty-five cases of intracranial giant serpentine aneurysms (GSΛs), including 61 cases reported in the literature and four additional cases presented in this study were reviewed. The clinical presentation, possible causes, natural history, and especially management of GSAs are discussed with emphasis on the need for aggressive intervention and multidisciplinary management. PMID:20667180

  11. Multidisciplinary disease management in rheumatology.

    PubMed

    Oliver, Susan

    2003-11-01

    With an increasingly ageing population, the number of patients with osteoarthritis and rheumatoid arthritis is expected to rise. High-quality patient education and self-management are essential in these chronic debilitating conditions. A multidisciplinary team has produced a template to guide the assessment, treatment and holistic care of patients in primary care.

  12. Designing Multidisciplinary Integrated Curriculum Units

    ERIC Educational Resources Information Center

    Clayton, Marla; Hagan, Jill; Ho, Pier Sun; Hudis, Paula M.

    2010-01-01

    The term "integrated curriculum" has many different, sometimes conflicting, meanings to educators. In this manual, integrated curriculum refers to the materials and pedagogical strategies used by "multidisciplinary" teams of teachers to organize their instruction so that students are encouraged to make meaningful connections…

  13. The First Pan-WCRP Workshop on Monsoon Climate Systems: Toward Better Prediction of the Monsoons

    SciTech Connect

    Sperber, K R; Yasunari, T

    2005-07-27

    In 2004 the Joint Scientific Committee (JSC) that provides scientific guidance to the World Climate Research Programme (WCRP) requested an assessment of (1) WCRP monsoon related activities and (2) the range of available observations and analyses in monsoon regions. The purpose of the assessment was to (a) define the essential elements of a pan-WCRP monsoon modeling strategy, (b) identify the procedures for producing this strategy, and (c) promote improvements in monsoon observations and analyses with a view toward their adequacy, and addressing any undue redundancy or duplication. As such, the WCRP sponsored the ''1st Pan-WCRP Workshop on Monsoon Climate Systems: Toward Better Prediction of the Monsoons'' at the University of California, Irvine, CA, USA from 15-17 June 2005. Experts from the two WCRP programs directly relevant to monsoon studies, the Climate Variability and Predictability Programme (CLIVAR) and the Global Energy and Water Cycle Experiment (GEWEX), gathered to assess the current understanding of the fundamental physical processes governing monsoon variability and to highlight outstanding problems in simulating the monsoon that can be tackled through enhanced cooperation between CLIVAR and GEWEX. The agenda with links to the presentations can be found at: http://www.clivar.org/organization/aamon/WCRPmonsoonWS/agenda.htm. Scientific motivation for a joint CLIVAR-GEWEX approach to investigating monsoons includes the potential for improved medium-range to seasonal prediction through better simulation of intraseasonal (30-60 day) oscillations (ISO's). ISO's are important for the onset of monsoons, as well as the development of active and break periods of rainfall during the monsoon season. Foreknowledge of the active and break phases of the monsoon is important for crop selection, the determination of planting times and mitigation of potential flooding and short-term drought. With a few exceptions simulations of ISO are typically poor in all classes of

  14. Multidisciplinary Techniques and Novel Aircraft Control Systems

    NASA Technical Reports Server (NTRS)

    Padula, Sharon L.; Rogers, James L.; Raney, David L.

    2000-01-01

    The Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO techniques such as sensitivity analysis, automatic differentiation, and genetic algorithms contribute to the design of novel control systems. In the test case, the design and use of distributed shape-change devices to provide low-rate maneuvering capability for a tailless aircraft is considered. The ability of MDO to add value to control system development is illustrated using results from several years of research funded by the Aircraft Morphing Program.

  15. Multidisciplinary Techniques and Novel Aircraft Control Systems

    NASA Technical Reports Server (NTRS)

    Padula, Sharon L.; Rogers, James L.; Raney, David L.

    2000-01-01

    The Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO techniques such as sensitivity analysis, automatic differentiation, and genetic algorithms contribute to the design of novel control systems. In the test case, the design and use of distributed shapechange devices to provide low-rate maneuvering capability for a tailless aircraft is considered. The ability of MDO to add value to control system development is illustrated using results from several years of research funded by the Aircraft Morphing Program.

  16. Integrated Multidisciplinary Optimization Objects

    NASA Technical Reports Server (NTRS)

    Alston, Katherine

    2014-01-01

    OpenMDAO is an open-source MDAO framework. It is used to develop an integrated analysis and design environment for engineering challenges. This Phase II project integrated additional modules and design tools into OpenMDAO to perform discipline-specific analysis across multiple flight regimes at varying levels of fidelity. It also showcased a refined system architecture that allows the system to be less customized to a specific configuration (i.e., system and configuration separation). By delivering a capable and validated MDAO system along with a set of example applications to be used as a template for future users, this work greatly expands NASA's high-fidelity, physics-based MDAO capabilities and enables the design of revolutionary vehicles in a cost-effective manner. This proposed work complements M4 Engineering's expertise in developing modeling and simulation toolsets that solve relevant subsonic, supersonic, and hypersonic demonstration applications.

  17. Pleistocene Indian Monsoon rainfall variability dominated by obliquity

    NASA Astrophysics Data System (ADS)

    Gebregiorgis, D.; Hathorne, E. C.; Giosan, L.; Collett, T. S.; Nuernberg, D.; Frank, M.

    2015-12-01

    The past variability of the Indian Monsoon is mostly known from records of wind strength over the Arabian Sea while Quaternary proxy records of Indian monsoon precipitation are still lacking. Here we utilize scanning x-ray fluorescence (XRF) data from a sediment core obtained by the IODP vessel JOIDES Resolution in the Andaman Sea (Site 17) to investigate changes in sediment supply from the peak monsoon precipitation regions to the core site. We use Ti/Ca and K/Rb ratios to trace changes in terrigenous flux and weathering regime, respectively, while Zr/Rb ratios suggest grain size variations. The age model of Site 17 is based on correlation of benthic C. wuellerstorfi/C. mundulus δ18O data to the LR04 global benthic δ18O stack at a resolution of ~3 kyr (Lisiecki and Raymo, 2005) for the last 2 Myrs. In its youngest part the age model is supported by five 14C ages on planktic foraminifera and the youngest Toba ash layer (Ali et al., 2015) resulting in a nearly constant sedimentation rate of ~6.5 cm/kyr. Frequency analysis of the 4 mm resolution Ti/Ca, K/Rb, and Zr/Rb time series using the REDFIT program (Schulz and Mudelsee, 2002), reveals the three main Milankovitch orbital cycles above the 90% confidence level. Depth domain spectral analysis reveals the presence of significant cyclicity at wavelengths of 28.5 and 2.8 m corresponding to the ~400 kyr and ~41 kyr cycles, respectively, during the last 2 Myr. These records suggest that Indian monsoon variability has varied in the obliquity and eccentricity bands, the latter in particular after the mid Pleistocene transition (MPT), while strong precession forcing is lacking in this super-high resolution record. Northern summer insolation and Southern Hemisphere latent heat export are out of phase during precessional cycles, but in phase in the obliquity band, which indicates that Indian monsoon precipitation has likely been more sensitive to both NH pull and SH push mechanisms (Clemens and Prell, 2003). References Ali

  18. The Joint Aerosol-Monsoon Experiment: A New Challenge to Monsoon Climate Research

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.

    2008-01-01

    Aerosol and monsoon related droughts and floods are two of the most serious environmental hazards confronting more than 60% of the population of the world living in the Asian monsoon countries. In recent years, thanks to improved satellite and in-situ observations, and better models, great strides have been made in aerosol, and monsoon research respectively. There is now a growing body of evidence suggesting that interaction of aerosol forcing with water cycle dynamics in monsoon regions may substantially alter the redistribution of energy at the earth surface and in the atmosphere, and therefore significantly impact monsoon rainfall variability and long term trends. In this talk, I will describe issues related to societal needs, scientific background, and challenges in studies of aerosol-water cycle interaction in Asian monsoon regions. As a first step towards addressing these issues, the authors call for an integrated observation and modeling research approach aimed at the interactions between aerosol chemistry and radiative effects and monsoon dynamics of the coupled ocean-atmosphere-land system. A Joint Aerosol-Monsoon Experiment (JAMEX) is proposed for 2007-2011, with an enhanced observation period during 2008-09, encompassing diverse arrays of observations from surface, aircraft, unmanned aerial vehicles, and satellites of physical and chemical properties of aerosols, long range aerosol transport as well as meteorological and oceanographic parameters in the Indo-Pacific Asian monsoon region. JAMEX will leverage on coordination among many ongoing and planned national programs on aerosols and monsoon research in China, India, Japan, Nepal, Italy, US, as well as international research programs of the World Climate Research Program (WCRP) and the World Meteorological Organization (WMO).

  19. Climatology of monsoon rains of Myanmar (Burma)

    NASA Astrophysics Data System (ADS)

    Roy, N. Sen; Kaur, Surinder

    2000-06-01

    Based on 33 years' rainfall data of Myanmar for the summer monsoon months (June-September), the detailed rainfall climatology of the country has been studied. Seasonal rainfall series are found to approximate to a Gaussian distribution. By using the rainfall distribution and coefficient of variation, it has been possible to divide the country into five homogeneous rainfall regions. Different statistical characteristics of the seasonal, monthly and zonal rainfall, as well as the whole country's rainfall, have been determined. Analysis of interannual and intraseasonal variability highlights the fact that the correlation between the rainfall of different months and zones is rather weak. Trend and periodicity of the rainfall series have been examined by different statistical techniques, indicating little evidence of a trend. The power spectrum of the rainfall series appears to show only marginal significance at the 95% level for an 11 year cycle. The rainfall series of Myanmar shows little correspondence with neighbouring Bangladesh and Northeast India, even though all of them are influenced by similar weather systems.

  20. Climatology and dynamics of nocturnal low-level stratus over the southern West African monsoon region

    NASA Astrophysics Data System (ADS)

    Fink, A. H.; Schuster, R.; Knippertz, P.; van der Linden, R.

    2013-12-01

    The southern parts of West Africa, from the coast to about 10°N, are frequently covered by an extensive deck of shallow, low (200 - 400 m above ground) stratus or stratocumulus clouds during the summer monsoon season. These clouds usually form at night in association with a nocturnal low-level jet (NLLJ) and can persist into the early afternoon hours until they are dissipated or replaced by fair-weather cumuli. Recent work suggests that the stratus deck and its effect on the surface radiation balance are unsatisfactorily represented in standard satellite retrievals and simulations by state-of-the-art climate models. We will present the first ever climatology of the diurnal cycle of the low cloud deck based on surface observations and satellite products. In addition, we use high-resolution regional simulations with the Weather Research and Forecast (WRF) model and observations from the African Monsoon Multidisciplinary Analysis (AMMA) 2006 campaign to investigate (a) the spatiotemporal distribution, (b) the influence on the radiation balance, and (c) the detailed formation and maintenance mechanisms of the stratiform clouds as simulated by the model. The model configuration used for this study has been determined following an extensive sensitivity study, which has shown that at least some configurations of WRF satisfactorily reproduce the diurnal cycle of the low cloud evolution. The main conclusions are: (a) The observed stratus deck forms after sunset along the coast, spreads inland in the course of the night, reaches maximum poleward extent at about 10°N around 09-10 local time and dissipates in the early afternoon. (b) The average surface net radiation balance in stratus-dominated regions is 35 W m-2 lower than in those with less clouds. (c) The cloud formation is related to a subtle balance between 'stratogenic' upward (downward) fluxes of latent (sensible) heat caused by shear-driven turbulence below the NLLJ, cold advection from the ocean, forced lifting at

  1. Characterization of southwest monsoon onset over Myanmar

    NASA Astrophysics Data System (ADS)

    Mie Sein, Z. M.; Islam, A. R. M. Towfiqul; Maw, K. W.; Moya, T. B.

    2015-10-01

    The aim of this paper was to characterize the southwest monsoon onset over Myanmar based on the model. The Regional Climate Model (RegCM3) was run for a period of 10 years (2000-2009) to simulate the meteorological fields which focused on April to July season. The model input data were obtained from the reanalyzed datasets of the National Center for Environmental Prediction (NCEP) and National Centre for Atmospheric Research (NCAR). Grell scheme with Arakawa closure for cumulus parameterization assumption was used for simulation with 45 km horizontal resolution. The results revealed that southwest monsoon onset was confirmed when the prevailing wind direction up to 600 hPa level had shifted from northeasterly to westerly or southwesterly. The southwest monsoon first arrived at southernmost Kawthoung station of Myanmar and progressed through the Deltaic and Central parts until it reached at northernmost Putao station. Over the simulation periods, the southwest monsoon onset progressed from the southernmost to northernmost parts of the country in 19 ± 10 days. The position of Intertropical Convergence Zone (ITCZ) appeared (23°N-28°N) over the Northern part of the country before the onset. Furthermore, 500 hPa ridge appeared consistently over the Deltaic area of Myanmar from 6 to 10 days before the monsoon onset. Its position is about 6° to the south of the ITCZ.

  2. Multidisciplinary Optimization of Airborne Radome Using Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Tang, Xinggang; Zhang, Weihong; Zhu, Jihong

    A multidisciplinary optimization scheme of airborne radome is proposed. The optimization procedure takes into account the structural and the electromagnetic responses simultaneously. The structural analysis is performed with the finite element method using Patran/Nastran, while the electromagnetic analysis is carried out using the Plane Wave Spectrum and Surface Integration technique. The genetic algorithm is employed for the multidisciplinary optimization process. The thicknesses of multilayer radome wall are optimized to maximize the overall transmission coefficient of the antenna-radome system under the constraint of the structural failure criteria. The proposed scheme and the optimization approach are successfully assessed with an illustrative numerical example.

  3. Astronomical and Hydrological Perspective of Mountain Impacts on the Asian Summer Monsoon

    PubMed Central

    He, Bian; Wu, Guoxiong; Liu, Yimin; Bao, Qing

    2015-01-01

    The Asian summer monsoon has great socioeconomic impacts. Understanding how the huge Tibetan and Iranian Plateaus affect the Asian summer monsoon is of great scientific value and has far-reaching significance for sustainable global development. One hypothesis considers the plateaus to be a shield for monsoon development in India by blocking cold-dry northerly intrusion into the tropics. Based on astronomical radiation analysis and numerical modeling, here we show that in winter the plateaus cannot block such a northerly intrusion; while in summer the daily solar radiation at the top of the atmosphere and at the surface, and the surface potential temperature to the north of the Tibetan Plateau, are higher than their counterparts to its south, and such plateau shielding is not needed. By virtue of hydrological analysis, we show that the high energy near the surface required for continental monsoon development is maintained mainly by high water vapor content. Results based on potential vorticity–potential temperature diagnosis further demonstrate that it is the pumping of water vapor from sea to land due to the thermal effects of the plateaus that breeds the Asian continental monsoon. PMID:26620727

  4. Astronomical and Hydrological Perspective of Mountain Impacts on the Asian Summer Monsoon.

    PubMed

    He, Bian; Wu, Guoxiong; Liu, Yimin; Bao, Qing

    2015-12-01

    The Asian summer monsoon has great socioeconomic impacts. Understanding how the huge Tibetan and Iranian Plateaus affect the Asian summer monsoon is of great scientific value and has far-reaching significance for sustainable global development. One hypothesis considers the plateaus to be a shield for monsoon development in India by blocking cold-dry northerly intrusion into the tropics. Based on astronomical radiation analysis and numerical modeling, here we show that in winter the plateaus cannot block such a northerly intrusion; while in summer the daily solar radiation at the top of the atmosphere and at the surface, and the surface potential temperature to the north of the Tibetan Plateau, are higher than their counterparts to its south, and such plateau shielding is not needed. By virtue of hydrological analysis, we show that the high energy near the surface required for continental monsoon development is maintained mainly by high water vapor content. Results based on potential vorticity-potential temperature diagnosis further demonstrate that it is the pumping of water vapor from sea to land due to the thermal effects of the plateaus that breeds the Asian continental monsoon.

  5. Simulation of the Asian summer monsoon with the CCC GCM-1

    SciTech Connect

    Zwiers, F.W. )

    1993-03-01

    The climate literature contains a considerable amount of indirect evidence that there is a connection between the size of the spring Tibetan snowpack and the strength of the subsequent Asian summer monsoon. This paper reports on a study that was conducted to search for evidence of a direct snow-monsoon interaction in a simulated climatology derived from two long integrations of the Canadian Climate Centre's GCM version 1. Statistical methods based on a combination of empirical orthogonal function analysis and canonical correlation analysis were the primary investigative tools. Only a weak signal was found. It is therefore concluded that either the simulated variability of the snow on Tibet is too small, the model does not react appropriately to the simulated variability, or the true natural snow-monsoon mechanism is weak and any snow-monsoon connection relies upon a third factor. The first possibility is considered to be remote: the model simulates substantial interannual variability of Tibetan snow. The second and third possibilities are more likely. In particular, the physical mechanism that is thought to connect Tibetan snow with the Asian monsoon may not be properly simulated in the model.

  6. Astronomical and Hydrological Perspective of Mountain Impacts on the Asian Summer Monsoon

    NASA Astrophysics Data System (ADS)

    He, Bian; Wu, Guoxiong; Liu, Yimin; Bao, Qing

    2015-12-01

    The Asian summer monsoon has great socioeconomic impacts. Understanding how the huge Tibetan and Iranian Plateaus affect the Asian summer monsoon is of great scientific value and has far-reaching significance for sustainable global development. One hypothesis considers the plateaus to be a shield for monsoon development in India by blocking cold-dry northerly intrusion into the tropics. Based on astronomical radiation analysis and numerical modeling, here we show that in winter the plateaus cannot block such a northerly intrusion; while in summer the daily solar radiation at the top of the atmosphere and at the surface, and the surface potential temperature to the north of the Tibetan Plateau, are higher than their counterparts to its south, and such plateau shielding is not needed. By virtue of hydrological analysis, we show that the high energy near the surface required for continental monsoon development is maintained mainly by high water vapor content. Results based on potential vorticity-potential temperature diagnosis further demonstrate that it is the pumping of water vapor from sea to land due to the thermal effects of the plateaus that breeds the Asian continental monsoon.

  7. Understanding land surface response to changing South Asian monsoon in a warming climate

    NASA Astrophysics Data System (ADS)

    Ramarao, M. V. S.; Krishnan, R.; Sanjay, J.; Sabin, T. P.

    2015-05-01

    Recent studies have drawn attention to a significant weakening trend of the South Asian monsoon circulation and an associated decrease in regional rainfall during the last few decades. While surface temperatures over the region have steadily risen during this period, most of the CMIP (Coupled Model Intercomparison Project) global climate models have difficulties in capturing the observed decrease of monsoon precipitation, thus limiting our understanding of the regional land surface response to monsoonal changes. This problem is investigated by performing two long-term simulation experiments, with and without anthropogenic forcing, using a variable resolution global climate model having high-resolution zooming over the South Asian region. The present results indicate that anthropogenic effects have considerably influenced the recent weakening of the monsoon circulation and decline of precipitation. It is seen that the simulated increase of surface temperature over the Indian region during the post-1950s is accompanied by a significant decrease of monsoon precipitation and soil moisture. Our analysis further reveals that the land surface response to decrease of soil moisture is associated with significant reduction in evapotranspiration over the Indian land region. A future projection, based on the representative concentration pathway 4.5 (RCP4.5) scenario of the Intergovernmental panel on Climate Change (IPCC), using the same high-resolution model indicates the possibility for detecting the summer-time soil drying signal over the Indian region during the 21st century, in response to climate change. While these monsoon hydrological changes have profound socioeconomic implications, the robustness of the high-resolution simulations provides deeper insights and enhances our understanding of the regional land surface response to the changing South Asian monsoon.

  8. Understanding land surface response to changing South Asian monsoon in a warming climate

    NASA Astrophysics Data System (ADS)

    Ramarao, M. V. S.; Krishnan, R.; Sanjay, J.; Sabin, T. P.

    2015-09-01

    Recent studies have drawn attention to a significant weakening trend of the South Asian monsoon circulation and an associated decrease in regional rainfall during the last few decades. While surface temperatures over the region have steadily risen during this period, most of the CMIP (Coupled Model Intercomparison Project) global climate models have difficulties in capturing the observed decrease of monsoon precipitation, thus limiting our understanding of the regional land surface response to monsoonal changes. This problem is investigated by performing two long-term simulation experiments, with and without anthropogenic forcing, using a variable resolution global climate model having high-resolution zooming over the South Asian region. The present results indicate that anthropogenic effects have considerably influenced the recent weakening of the monsoon circulation and decline of precipitation. It is seen that the simulated increase of surface temperature over the Indian region during the post-1950s is accompanied by a significant decrease of monsoon precipitation and soil moisture. Our analysis further reveals that the land surface response to decrease of soil moisture is associated with significant reduction in evapotranspiration over the Indian land region. A future projection, based on the representative concentration pathway 4.5 (RCP4.5) scenario of the Intergovernmental Panel on Climate Change (IPCC), using the same high-resolution model indicates the possibility for detecting the summer-time soil drying signal over the Indian region during the 21st century in response to climate change. Given that these monsoon hydrological changes have profound socio-economic implications the present findings provide deeper insights and enhance our understanding of the regional land surface response to the changing South Asian monsoon. While this study is based on a single model realization, it is highly desirable to have multiple realizations to establish the robustness

  9. Monsoon control on faunal composition of planktic foraminifera in the Arabian Sea

    NASA Astrophysics Data System (ADS)

    Munz, P.; Siccha, M.; Kucera, M.; Schulz, H.

    2013-12-01

    Being among the most productive open ocean basins, sea surface properties in the Arabian Sea are highly influenced by the seasonal reversal of the monsoonal wind system. During boreal summer wind direction from the southwest induces strong upwelling along the coast off Somalia and Oman. Vertical transport of cold and nutrient-rich deep-water masses by Ekman pumping reduces sea surface temperature and triggers primary productivity. Reversed cold and dry winds during boreal winter lead to cooling of the surface- and subsurface-waters and hereby to deep convective mixing, bringing nutrients into the photic zone and enhancing primary productivity especially in the northern part of the Arabian Sea. Here, we study the influence of the different seasonal monsoon systems on the faunal composition of planktic foraminifera, in order to improve our understanding how the faunal community record is influenced by the respective monsoon systems and to provide baseline information for the reconstruction of ancient monsoon conditions. We used published core-top foraminiferal databases, significantly increased in spatial coverage by new contributions. The resulting combined database consists of 413 core-top samples spanning the Arabian Sea and the Northern Indian Ocean to 10° S. The seasonal sea surface properties at these stations could be binned into categories of different monsoon influence, based on satellite-derived chlorophyll-a concentrations. Interpretation of species response to environmental control is based on multivariate statistical analyses of each of the categorical bins. First results show that samples influenced only by winter- and summer monsoon conditions, respectively, feature specifiable faunal composition. Globigerina bulloides is mostly associated with summer upwelling conditions, whereas Globigerina falconensis and Pulleniatina obliquiloculata are typical species of winter conditions. Redundancy analysis reveals preferences of species populations with

  10. Information Management for a Large Multidisciplinary Project

    NASA Technical Reports Server (NTRS)

    Jones, Kennie H.; Randall, Donald P.; Cronin, Catherine K.

    1992-01-01

    In 1989, NASA's Langley Research Center (LaRC) initiated the High-Speed Airframe Integration Research (HiSAIR) Program to develop and demonstrate an integrated environment for high-speed aircraft design using advanced multidisciplinary analysis and optimization procedures. The major goals of this program were to evolve the interactions among disciplines and promote sharing of information, to provide a timely exchange of information among aeronautical disciplines, and to increase the awareness of the effects each discipline has upon other disciplines. LaRC historically has emphasized the advancement of analysis techniques. HiSAIR was founded to synthesize these advanced methods into a multidisciplinary design process emphasizing information feedback among disciplines and optimization. Crucial to the development of such an environment are the definition of the required data exchanges and the methodology for both recording the information and providing the exchanges in a timely manner. These requirements demand extensive use of data management techniques, graphic visualization, and interactive computing. HiSAIR represents the first attempt at LaRC to promote interdisciplinary information exchange on a large scale using advanced data management methodologies combined with state-of-the-art, scientific visualization techniques on graphics workstations in a distributed computing environment. The subject of this paper is the development of the data management system for HiSAIR.

  11. Establishing a framework for building multidisciplinary programs

    PubMed Central

    Meguid, Cheryl; Ryan, Carrie E; Edil, Barish H; Schulick, Richard D; Gajdos, Csaba; Boniface, Megan; Schefter, Tracey E; Purcell, W Thomas; McCarter, Martin

    2015-01-01

    While most providers support the concept of a multidisciplinary approach to patient care, challenges exist to the implementation of successful multidisciplinary clinical programs. As patients become more knowledgeable about their disease through research on the Internet, they seek hospital programs that offer multidisciplinary care. At the University of Colorado Hospital, we utilize a formal multidisciplinary approach across a variety of clinical settings, which has been beneficial to patients, providers, and the hospital. We present a reproducible framework to be used as a guide to develop a successful multidisciplinary program. PMID:26664132

  12. Future projection of mean and variability of the Asian Summer Monsoon and Indian Ocean Climate systems

    SciTech Connect

    Annamalai, H.

    2014-09-15

    The overall goal of this project is to assess the ability of the CMIP3/5 models to simulate the Indian-Ocean monsoon systems. The PI along with post-docs investigated research issues ranging from synoptic systems to long-term trends over the Asian monsoon region. The PI applied diagnostic tools such as moist static energy (MSE) to isolate: the moist and radiative processes responsible for extended monsoon breaks over South Asia, precursors in the ENSO-monsoon association, reasons for the drying tendency over South Asia and the possible effect on tropical Indian Ocean climate anomalies influencing certain aspects of ENSO characteristics. By diagnosing various observations and coupled model simulations, we developed working hypothesis and tested them by carrying out sensitivity experiments with both linear and nonlinear models. Possible physical and dynamical reasons for model sensitivities were deduced. On the teleconnection front, the ability of CMIP5 models in representing the monsoon-desert mechanism was examined recently. Further more, we have applied a suite of diagnostics and have performed an in depth analysis on CMIP5 integrations to isolate the possible reasons for the ENSO-monsoon linkage or lack thereof. The PI has collaborated with Dr. K.R. Sperber of PCMDI and other CLIVAR Asian-Australian monsoon panel members in understanding the ability of CMIP3/5 models in capturing monsoon and its spectrum of variability. The objective and process-based diagnostics aided in selecting models that best represent the present-day monsoon and its variability that are then employed for future projections. Two major highlights were an invitation to write a review on present understanding monsoons in a changing climate in Nature Climate Change, and identification of an east-west shift in observed monsoon rainfall (more rainfall over tropical western Pacific and drying tendency over South Asia) in the last six decades and attributing that shift to SST rise over the tropical

  13. Getting a grip on Indian Ocean monsoons

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    An improved understanding of the Indian Ocean monsoon season could help researchers to better forecast floods and the associated spread of cholera in low-lying Bangladesh.In a joint effort by the University of Colorado at Boulder, the Asian Disaster Preparedness Center, and the Bangladesh government, researchers are using a variety of monitoring and forecast modeling tools to better understand and characterize the monsoon season's active and calm periods. By studying Indian Ocean climatic conditions and probabilities that lead to regular flooding of the Bangladesh delta, researchers also can provide probabilities concerning outbreaks of cholera, an intestinal disease that infects large segments of that country's population.

  14. Indian monsoon variations during three contrasting climatic periods: the Holocene, Heinrich Stadial 2 and the last interglacial-glacial transition

    NASA Astrophysics Data System (ADS)

    Zorzi, Coralie; Fernanda Sanchez Goñi, Maria; Anupama, Krishnamurthy; Prasad, Srinivasan; Hanquiez, Vincent; Johnson, Joel; Giosan, Liviu

    2016-04-01

    In contrast to the East Asian and African monsoons the Indian monsoon is still poorly documented throughout the last climatic cycle (last 135,000 years). Pollen analysis from two marine sediment cores (NGHP-01-16A and NGHP-01-19B) collected from the offshore Godavari and Mahanadi basins, both located in the Core Monsoon Zone (CMZ) reveals changes in Indian summer monsoon variability and intensity during three contrasting climatic periods: the Holocene, the Heinrich Stadial (HS) 2 and the Marine Isotopic Stage (MIS) 5/4 during the ice sheet growth transition. During the first part of the Holocene between 11,300 and 4,200 cal years BP, characterized by high insolation (minimum precession, maximum obliquity), the maximum extension of the coastal forest and mangrove reflects high monsoon rainfall. This climatic regime contrasts with that of the second phase of the Holocene, from 4,200 cal years BP to the present, marked by the development of drier vegetation in a context of low insolation (maximum precession, minimum obliquity). The historical period in India is characterized by an alternation of strong and weak monsoon centennial phases that may reflect the Medieval Climate Anomaly and the Little Ice Age, respectively. During the HS 2, a period of low insolation and extensive iceberg discharge in the North Atlantic Ocean, vegetation was dominated by grassland and dry flora indicating pronounced aridity as the result of a weak Indian summer monsoon. The MIS 5/4 glaciation, also associated with low insolation but moderate freshwater fluxes, was characterized by a weaker reduction of the Indian summer monsoon and a decrease of seasonal contrast as recorded by the expansion of dry vegetation and the development of Artemisia, respectively. Our results support model predictions suggesting that insolation changes control the long term trend of the Indian monsoon precipitation, but its millennial scale variability and intensity are instead modulated by atmospheric

  15. Indian monsoon variations during three contrasting climatic periods: The Holocene, Heinrich Stadial 2 and the last interglacial-glacial transition

    NASA Astrophysics Data System (ADS)

    Zorzi, Coralie; Sanchez Goñi, Maria Fernanda; Anupama, Krishnamurthy; Prasad, Srinivasan; Hanquiez, Vincent; Johnson, Joel; Giosan, Liviu

    2015-10-01

    In contrast to the East Asian and African monsoons the Indian monsoon is still poorly documented throughout the last climatic cycle (last 135,000 years). Pollen analysis from two marine sediment cores (NGHP-01-16A and NGHP-01-19B) collected from the offshore Godavari and Mahanadi basins, both located in the Core Monsoon Zone (CMZ) reveals changes in Indian summer monsoon variability and intensity during three contrasting climatic periods: the Holocene, the Heinrich Stadial (HS) 2 and the Marine Isotopic Stage (MIS) 5/4 during the ice sheet growth transition. During the first part of the Holocene between 11,300 and 4200 cal years BP, characterized by high insolation (minimum precession, maximum obliquity), the maximum extension of the coastal forest and mangrove reflects high monsoon rainfall. This climatic regime contrasts with that of the second phase of the Holocene, from 4200 cal years BP to the present, marked by the development of drier vegetation in a context of low insolation (maximum precession, minimum obliquity). The historical period in India is characterized by an alternation of strong and weak monsoon centennial phases that may reflect the Medieval Climate Anomaly and the Little Ice Age, respectively. During the HS 2, a period of low insolation and extensive iceberg discharge in the North Atlantic Ocean, vegetation was dominated by grassland and dry flora indicating pronounced aridity as the result of a weak Indian summer monsoon. The MIS 5/4 glaciation, also associated with low insolation but moderate freshwater fluxes, was characterized by a weaker reduction of the Indian summer monsoon and a decrease of seasonal contrast as recorded by the expansion of dry vegetation and the development of Artemisia, respectively. Our results support model predictions suggesting that insolation changes control the long term trend of the Indian monsoon precipitation, but its millennial scale variability and intensity are instead modulated by atmospheric

  16. Simulation of the Indian and East-Asian summer monsoon in the ECMWF model: Sensitivity to horizontal resolution

    SciTech Connect

    Sperber, K.R.; Potter, G.L.; Boyle, J.S.; Hameed, S.

    1993-11-01

    The ability of the ECMWF model (Cycle 33) to simulate the Indian and East Asian summer monsoon is evaluated at four different horizontal resolutions: T21, T42, T63, and T106. Generally, with respect to the large scale features of the circulation, the largest differences among the simulations occur at T42 relative to T21. However, on regional scales, important differences among the high frequency temporal variabilitY serve as a further critical test of the model`s ability to simulate the monsoon. More generally, the results indicate the importance of evaluating high frequency time scales as a component of the climate system. T106 best captures both the spatial and temporal characteristics of the Indian and East Asian Monsoon, while T42 fails to correctly simulate the sequence and development of synoptic scale milestones that characterize the monsoon flow. In particular, T106 is superior at simulating the development and migration of the monsoon trough over the Bay of Bengal. In the T42 simulation, the development of the monsoon occurs one month earlier than typically observed. At this time the trough is incorrectly located adjacent to the east coast of India which results in an underestimate of precipitation over the Burma/Thailand region. This early establishment of the monsoon trough affects the evolution of the East-Asian monsoon and yields excessive preseason rainfall over the Mei-yu region. EOF analysis of precipitation over China indicates that T106 best simulates the Mei-yu mode of variability associated with an oscillation of the rainband that gives rise to periods of enhanced rainfall over the Yangize River Valley. The coarse resolution of T21 precludes simulation of the aforementioned regional scale monsoon flows.

  17. Interannual variability of the Indian monsoon and the Southern Oscillation

    SciTech Connect

    Wu, M.; Hastenrath, S.

    1986-01-01

    Years with abundant Southwest monsoon rainfall in India are characterized by anomalously low pressure over South Asia and the adjacent waters, enhanced cross-equatorial flow in the western, and increased cloudiness over the northern portion of the Indian Ocean, continuing from the pre-monsoon through the post-monsoon season; positive temperature anomalies over land and in the Arabian Sea in the pre-monsoon season, changing to negative departures after the monsoon onset. The following causality chain is suggested: the anomalously warm surfaces of south Asia and the adjacent ocean in the pre-monsoon season induce a thermal low, thus enhancing the northward directed pressure gradient, and favoring a vigorous cross-equatorial flow over the Indian Ocean. After the monsoon onset the land surfaces are cooled by evaporation, and the Arabian Sea surface waters by various wind stress effects. However, latent heat release over South Asia can now maintain the meridional topography gradients essential to the monsoon circulation. The positive phase of the Southern Oscillation (high pressure over the Eastern South Pacific) is associated with circulation departures in the Indian Ocean sector similar to those characteristic of years with abundant India monsoon rainfall. Abundant rainfall over India during the northern summer monsoon leads the positive mode of the southern Oscillation, and this in turn leads Java rainfall, whose peak is timed about half a year after that of India. A rising Southern Oscillation tendency presages abundant India Southwest Monsoon rainfall but a late monsoon onset. 46 references, 9 figures, 4 tables.

  18. Transport pathways of peroxyacetyl nitrate in the upper troposphere and lower stratosphere from different monsoon systems during the summer monsoon season

    NASA Astrophysics Data System (ADS)

    Fadnavis, S.; Semeniuk, K.; Schultz, M. G.; Kiefer, M.; Mahajan, A.; Pozzoli, L.; Sonbawane, S.

    2015-10-01

    The Asian summer monsoon involves complex transport patterns with large-scale redistribution of trace gases in the upper troposphere and lower stratosphere (UTLS). We employ the global chemistry-climate model ECHAM5-HAMMOZ in order to evaluate the transport pathways and the contributions of nitrogen oxide species peroxyacetyl nitrate (PAN), NOx and HNO3 from various monsoon regions, to the UTLS over southern Asia and vice versa. Simulated long-term seasonal mean mixing ratios are compared with trace gas retrievals from the Michelson Interferometer for Passive Atmospheric Sounding aboard ENVISAT(MIPAS-E) and aircraft campaigns during the monsoon season (June-September) in order to evaluate the model's ability to reproduce these transport patterns. The model simulations show that there are three regions which contribute substantial pollution to the South Asian UTLS: the Asian summer monsoon (ASM), the North American monsoon (NAM) and the West African monsoon (WAM). However, penetration due to ASM convection reaches deeper into the UTLS compared to NAM and WAM outflow. The circulation in all three monsoon regions distributes PAN into the tropical latitude belt in the upper troposphere (UT). Remote transport also occurs in the extratropical UT where westerly winds drive North American and European pollutants eastward where they can become part of the ASM convection and lifted into the lower stratosphere. In the lower stratosphere the injected pollutants are transported westward by easterly winds. Sensitivity experiments with ECHAM5-HAMMOZ for simultaneous NOx and non-methane volatile organic compounds (NMVOCs) emission change (-10 %) over ASM, NAM and WAM confirm similar transport. Our analysis shows that a 10 % change in Asian emissions transports ~ 5-30 ppt of PAN in the UTLS over Asia, ~ 1-10 ppt of PAN in the UTLS of northern subtropics and mid-latitudes, ~ 7-10 ppt of HNO3 and ~ 1-2 ppb of ozone in UT over Asia. Comparison of emission change over Asia, North

  19. Monsoon-driven vertical fluxes of organic pollutants in the western Arabian Sea

    SciTech Connect

    Dachs, J.; Bayona, J.M.; Ittekkot, V.; Albaiges, J.

    1999-11-15

    A time series of sinking particles from the western Arabian Sea was analyzed for aliphatic and polycyclic aromatic hydrocarbons, polychlorinated biphenyls, 4,4{prime}-DDT and 4,4{prime}-DDE, to assess the role of monsoons on their vertical flux in the Indian Ocean. Concurrently, molecular markers such as sterols and linear and branched alkanes were analyzed enabling the characterization of the biogenic sources and biogeochemical processes occurring during the sampling period. Hierarchical cluster analysis (HCA) of the data set of concentrations and fluxes of these compounds confirmed a seasonal variability driven by the SW and NE monsoons. Moreover, the influence of different air masses is evidenced by the occurrence of higher concentrations of DDT, PCBs, and pyrolytic PAHs during the NE monsoon and of fossil hydrocarbons during the SW monsoon. Total annual fluxes to the deep Arabian Sea represent an important removal contribution of persistent organic pollutants, thus not being available for the global distillation process (volatilization and atmospheric transport from low or mid latitudes to cold areas). Therefore, monsoons may play a significant role on the global cycle of organic pollutants.

  20. Radiative effects of black carbon aerosols on Indian monsoon: a study using WRF-Chem model

    NASA Astrophysics Data System (ADS)

    Soni, Pramod; Tripathi, Sachchida Nand; Srivastava, Rajesh

    2017-02-01

    The Weather Research and Forecasting model with Chemistry (WRF-Chem) is utilized to examine the radiative effects of black carbon (BC) aerosols on the Indian monsoon, for the year 2010. Five ensemble simulations with different initial conditions (1st to 5th December, 2009) were performed and simulation results between 1st January, 2010 to 31st December, 2010 were used for analysis. Most of the BC which stays near the surface during the pre-monsoon season gets transported to higher altitudes with the northward migration of the Inter Tropical Convergence Zone (ITCZ) during the monsoon season. In both the seasons, strong negative SW anomalies are present at the surface along with positive anomalies in the atmosphere, which results in the surface cooling and lower tropospheric heating, respectively. During the pre-monsoon season, lower troposphere heating causes increased convection and enhanced meridional wind circulation, bringing moist air from Indian Ocean and Bay of Bengal to the North-East India, leading to increased rainfall there. However, during the monsoon season, along with cooling over the land regions, a warming over the Bay of Bengal is simulated. This differential heating results in an increased westerly moisture flux anomaly over central India, leading to increased rainfall over northern parts of India but decreased rainfall over southern parts. Decreased rainfall over southern India is also substantiated by the presence of increased evaporation over Bay of Bengal and decrease over land regions.

  1. Meridional Propagation of the MJO/ISO and Prediction of Off-equatorial Monsoon Variability

    NASA Technical Reports Server (NTRS)

    Wu, Man Li C.; Schubert, S.; Suarez, M.; Pegion, P.; Waliser, D.

    2003-01-01

    This study was examine the links between tropical heating, the Madden Julian Oscillation (MJO)/Intraseasonal Oscillation (ISO), and the off-equatorial monsoon development. We examine both observations and idealized "MJO heating" experiments employing the NASA Seasonal-Interannual Prediction Project (NSIPP) atmospheric general circulation model (AGCM). In the simulations, the model is forced by climatological SST and an idealized eastward propagating heating profile that is meant 'to mimic the canonical heating associated with the MJO in the Indian Ocean and western Pacific. The observational analysis highlights the strong link between the Indian summer monsoon and the tropical ISO/MJO activity and heating. Here we focus on the potential for skillful predictions of the monsoon on sub-seasonal time scales associated with the meridional propagation of the ISO/MJO. In particular, we show that the variability of the Indian summer monsoon lags behind the variability of tropical ISO/MJO heating by about 15 days when the tropical heating is around 60E and 90E. This feature of the ISO/MJO is reproduced in the AGCM experiments with the idealized eastward propagating MJO-like heating, suggesting that models with realistic ISO/MJO variability should provide useful skill of monsoon breaks and surges on sub-seasonal time scales.

  2. Meridional Propagation of the MJO/ISO and Prediction of Off-equatorial Monsoon Variability

    NASA Technical Reports Server (NTRS)

    Wu, Man Li C.; Schubert, S.; Suarez, M.; Pegion, P.; Bacmeister, J.; Waliser, D.

    2004-01-01

    In this study we examine the links between tropical heating, the Madden Julian Oscillation (MJO)/Intraseasonal Oscillation (ISO), and the off-equatorial monsoon development. We examine both observations and idealized "MJO heating" experiments employing the NASA Seasonal-Interannual Prediction Project (NSIPP) atmospheric general circulation model (AGCM). In the simulations, the model is forced by climatological SST and an idealized eastward propagating heating profile that is meant to mimic the canonical heating associated with the MJO in the Indian Ocean and western Pacific. The observational analysis highlights the strong link between the Indian summer monsoon and the tropical ISO/MJO activity and heating. Here we focus on the potential for skillful predictions of the monsoon on subseasonal time scales associated with the meridional propagation of the ISOMJO. In particular, we show that the variability of the Indian summer monsoon lags behind the variability of tropical ISOMJO heating by about 15 days when the tropical heating is around 60E and 90E. This feature of the ISOMJO is reproduced in the AGCM experiments with the idealized eastward propagating MJO-like heating, suggesting that models with realistic ISOM0 variability should provide useful skill of monsoon breaks and surges on subseasonal time scales.

  3. Contrasting influences of aerosols on cloud properties during deficient and abundant monsoon years.

    PubMed

    Patil, Nitin; Dave, Prashant; Venkataraman, Chandra

    2017-03-24

    Direct aerosol radiative forcing facilitates the onset of Indian monsoon rainfall, based on synoptic scale fast responses acting over timescales of days to a month. Here, we examine relationships between aerosols and coincident clouds over the Indian subcontinent, using observational data from 2000 to 2009, from the core monsoon region. Season mean and daily timescales were considered. The correlation analyses of cloud properties with aerosol optical depth revealed that deficient monsoon years were characterized by more frequent and larger decreases in cloud drop size and ice water path, but increases in cloud top pressure, with increases in aerosol abundance. The opposite was observed during abundant monsoon years. The correlations of greater aerosol abundance, with smaller cloud drop size, lower evidence of ice processes and shallower cloud height, during deficient rainfall years, imply cloud inhibition; while those with larger cloud drop size, greater ice processes and a greater cloud vertical extent, during abundant rainfall years, suggest cloud invigoration. The study establishes that continental aerosols over India alter cloud properties in diametrically opposite ways during contrasting monsoon years. The mechanisms underlying these effects need further analysis.

  4. Contrasting influences of aerosols on cloud properties during deficient and abundant monsoon years

    NASA Astrophysics Data System (ADS)

    Patil, Nitin; Dave, Prashant; Venkataraman, Chandra

    2017-03-01

    Direct aerosol radiative forcing facilitates the onset of Indian monsoon rainfall, based on synoptic scale fast responses acting over timescales of days to a month. Here, we examine relationships between aerosols and coincident clouds over the Indian subcontinent, using observational data from 2000 to 2009, from the core monsoon region. Season mean and daily timescales were considered. The correlation analyses of cloud properties with aerosol optical depth revealed that deficient monsoon years were characterized by more frequent and larger decreases in cloud drop size and ice water path, but increases in cloud top pressure, with increases in aerosol abundance. The opposite was observed during abundant monsoon years. The correlations of greater aerosol abundance, with smaller cloud drop size, lower evidence of ice processes and shallower cloud height, during deficient rainfall years, imply cloud inhibition; while those with larger cloud drop size, greater ice processes and a greater cloud vertical extent, during abundant rainfall years, suggest cloud invigoration. The study establishes that continental aerosols over India alter cloud properties in diametrically opposite ways during contrasting monsoon years. The mechanisms underlying these effects need further analysis.

  5. Contrasting influences of aerosols on cloud properties during deficient and abundant monsoon years

    PubMed Central

    Patil, Nitin; Dave, Prashant; Venkataraman, Chandra

    2017-01-01

    Direct aerosol radiative forcing facilitates the onset of Indian monsoon rainfall, based on synoptic scale fast responses acting over timescales of days to a month. Here, we examine relationships between aerosols and coincident clouds over the Indian subcontinent, using observational data from 2000 to 2009, from the core monsoon region. Season mean and daily timescales were considered. The correlation analyses of cloud properties with aerosol optical depth revealed that deficient monsoon years were characterized by more frequent and larger decreases in cloud drop size and ice water path, but increases in cloud top pressure, with increases in aerosol abundance. The opposite was observed during abundant monsoon years. The correlations of greater aerosol abundance, with smaller cloud drop size, lower evidence of ice processes and shallower cloud height, during deficient rainfall years, imply cloud inhibition; while those with larger cloud drop size, greater ice processes and a greater cloud vertical extent, during abundant rainfall years, suggest cloud invigoration. The study establishes that continental aerosols over India alter cloud properties in diametrically opposite ways during contrasting monsoon years. The mechanisms underlying these effects need further analysis. PMID:28337991

  6. Ecosystem Response to Monsoon Rainfall Variability in Southwestern North America

    NASA Astrophysics Data System (ADS)

    Forzieri, Giovanni; Feyen, Luc; Vivoni, Enrique

    2013-04-01

    Due to its marked plant phenology driven by precipitation, the North American Monsoon System (NAMS) can serve to reveal ecological responses to climate variability and change in water-controlled regions. This study attempts to elucidate the effects of monsoon rainfall variability on vegetation dynamics over the North American Monsoon Experiment (NAME) tier I domain (20°-35° N, 105°-115° W). To this end, we analyze long-term dynamics (1982-2004) in seasonal precipitation (Pr), net primary production (NPP) and rain-use efficiency (RUE) based on phenological and biophysical memory metrics from NOAA CPC daily 1° gridded precipitation data and satellite GIMMS semi-monthly NDVI images at 8-km resolution. We focus our analysis on six diverse ecosystems spanning from semi-arid and desert environments to tropical deciduous forests to investigate: 1) the spatially averaged NPP/RUE profiles along the regional Pr gradient, 2) the linkage between NPP and Pr inter-annual variations and 3) the long-term trends of Pr, NPP and RUE. All the biomes show an increase (decrease) in mean NPP (RUE) along the mean seasonal precipitation gradient ranging from 100 to 900 mm. Variations in NPP/RUE profiles differ strongly across ecosystems and show threshold behaviors likely resulting from different physiological responses to climate effects and landscape features. Statistical analysis suggests that the inter-annual variability in NPP is significantly related to the temporal variability in precipitation. In particular, we found that forest biomes are more sensitive to inter-annual variations in precipitation regimes. Semi-arid ecosystems appear to be more resilient, probably because they are more exposed to extreme conditions and consequently better adapted to greater inter and intra-annual climate variability. The long-term positive signal in RUE imposed on its inter-annual variability, which results from a constant NPP under negative long-term trends of Pr, indicates an improved

  7. ASTROS: A multidisciplinary automated structural design tool

    NASA Technical Reports Server (NTRS)

    Neill, D. J.

    1989-01-01

    ASTROS (Automated Structural Optimization System) is a finite-element-based multidisciplinary structural optimization procedure developed under Air Force sponsorship to perform automated preliminary structural design. The design task is the determination of the structural sizes that provide an optimal structure while satisfying numerous constraints from many disciplines. In addition to its automated design features, ASTROS provides a general transient and frequency response capability, as well as a special feature to perform a transient analysis of a vehicle subjected to a nuclear blast. The motivation for the development of a single multidisciplinary design tool is that such a tool can provide improved structural designs in less time than is currently needed. The role of such a tool is even more apparent as modern materials come into widespread use. Balancing conflicting requirements for the structure's strength and stiffness while exploiting the benefits of material anisotropy is perhaps an impossible task without assistance from an automated design tool. Finally, the use of a single tool can bring the design task into better focus among design team members, thereby improving their insight into the overall task.

  8. Progress in multidisciplinary design optimization at NASA Langley

    NASA Technical Reports Server (NTRS)

    Padula, Sharon L.

    1993-01-01

    Multidisciplinary Design Optimization refers to some combination of disciplinary analyses, sensitivity analysis, and optimization techniques used to design complex engineering systems. The ultimate objective of this research at NASA Langley Research Center is to help the US industry reduce the costs associated with development, manufacturing, and maintenance of aerospace vehicles while improving system performance. This report reviews progress towards this objective and highlights topics for future research. Aerospace design problems selected from the author's research illustrate strengths and weaknesses in existing multidisciplinary optimization techniques. The techniques discussed include multiobjective optimization, global sensitivity equations and sequential linear programming.

  9. Enhancement of inland penetration of monsoon depressions in the Bay of Bengal due to prestorm ground wetness

    NASA Astrophysics Data System (ADS)

    Kishtawal, C. M.; Niyogi, Dev; Rajagopalan, Balaji; Rajeevan, M.; Jaiswal, N.; Mohanty, U. C.

    2013-06-01

    Observations of 408 monsoon low-pressure systems (MLPSs) including 196 monsoon depressions (MDs) that formed in the Bay of Bengal during the 1951-2007 period, and the gridded analysis of daily rainfall fields for the same period, were used to identify the association of antecedent rainfall (1 week average rainfall prior to the genesis of MLPS) with the genesis of MLPS and length of inland penetration by MDs. Prestorm rainfall is treated as a surrogate to prestorm ground wetness conditions due to unavailability of historical soil-moisture data over the monsoon region. These observations were analyzed using self-organizing maps (SOMs) to group nine different prestorm monsoon rainfall patterns into different transition states like active, active-to-break, break-to-active, break, etc. The analysis indicates that MLPS are four times more likely to form on a day during active monsoon state compared to break state. Analysis of MLPSs linked to each monsoon state represented by SOM nodes shows that MDs with higher inland penetration were associated with higher antecedent rainfall. On the other hand, there was no significant difference in low-level atmospheric circulation for MDs with shortest and longest inland penetration.

  10. Warm Indian Ocean, Weak Asian Monsoon

    NASA Astrophysics Data System (ADS)

    Koll Roxy, Mathew; Ritika, Kapoor; Terray, Pascal; Murtugudde, Raghu; Ashok, Karumuri; Nath Goswami, Buphendra

    2015-04-01

    There are large uncertainties looming over the status and fate of the South Asian monsoon in a changing climate. Observations and climate models have suggested that anthropogenic warming in the past century has increased the moisture availability and the land-sea thermal contrast in the tropics, favoring an increase in monsoon rainfall. In contrast, we notice that South Asian subcontinent experienced a relatively subdued warming during this period. At the same time, the tropical Indian Ocean experienced a nearly monotonic warming, at a rate faster than the other tropical oceans. Using long-term observations and coupled model experiments, we suggest that the enhanced Indian Ocean warming along with the suppressed warming of the subcontinent weaken the land-sea thermal contrast throughout the troposphere, dampen the monsoon Hadley circulation, and reduce the rainfall over South Asia. As a result, the summer monsoon rainfall during 1901-2012 shows a significant weakening trend over South Asia, extending from Pakistan through central India to Bangladesh.

  11. Palaeoclimatic insights into forcing and response of monsoon rainfall.

    PubMed

    Mohtadi, Mahyar; Prange, Matthias; Steinke, Stephan

    2016-05-12

    Monsoons are the dominant seasonal mode of climate variability in the tropics and are critically important conveyors of atmospheric moisture and energy at a global scale. Predicting monsoons, which have profound impacts on regions that are collectively home to more than 70 per cent of Earth's population, is a challenge that is difficult to overcome by relying on instrumental data from only the past few decades. Palaeoclimatic evidence of monsoon rainfall dynamics across different regions and timescales could help us to understand and predict the sensitivity and response of monsoons to various forcing mechanisms. This evidence suggests that monsoon systems exhibit substantial regional character.

  12. Palaeoclimatic insights into forcing and response of monsoon rainfall

    NASA Astrophysics Data System (ADS)

    Mohtadi, Mahyar; Prange, Matthias; Steinke, Stephan

    2016-05-01

    Monsoons are the dominant seasonal mode of climate variability in the tropics and are critically important conveyors of atmospheric moisture and energy at a global scale. Predicting monsoons, which have profound impacts on regions that are collectively home to more than 70 per cent of Earth’s population, is a challenge that is difficult to overcome by relying on instrumental data from only the past few decades. Palaeoclimatic evidence of monsoon rainfall dynamics across different regions and timescales could help us to understand and predict the sensitivity and response of monsoons to various forcing mechanisms. This evidence suggests that monsoon systems exhibit substantial regional character.

  13. Decadal Prediction and Stochastic Simulation of Hydroclimate Over Monsoonal Asia

    SciTech Connect

    Ghil, Michael; Robertson, Andrew W.; Cook, Edward R.; D’Arrigo, Rosanne; Lall, Upmanu; Smyth, Padhraic J.

    2015-01-18

    We developed further our advanced methods of time series analysis and empirical model reduction (EMR) and applied them to climatic time series relevant to hydroclimate over Monsoonal Asia. The EMR methodology was both generalized further and laid on a rigorous mathematical basis via multilayered stochastic models (MSMs). We identified easily testable conditions that imply the existence of a global random attractor for MSMs and allow for non-polynomial predictors. This existence, in turn, guarantees the numerical stability of the MSMs so obtained. We showed that, in the presence of low-frequency variability (LFV), EMR prediction can be improved further by including information from selected times in the system’s past. This prediction method, dubbed Past-Noise Forecasting (PNF), was successfully applied to the Madden-Julian Oscillation (MJO). Our time series analysis and forecasting methods, based on singular-spectrum analysis (SSA) and its enhancements, were applied to several multi-centennial proxy records provided by the Lamont team. These included the Palmer Drought Severity Index (PDSI) for 1300–2005 from the Monsoonal Asia Drought Atlas (MADA), and a 300-member ensemble of pseudo-reconstructions of Indus River discharge for 1702–2005. The latter was shown to exhibit a robust 27-yr low-frequency mode, which helped multi-decadal retroactive forecasts with no look-ahead over this 300-year interval.

  14. Multidisciplinary design optimization - An emerging new engineering discipline

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, Jaroslaw

    1993-01-01

    A definition of the multidisciplinary design optimization (MDO) is introduced, and functionality and relationship of the MDO conceptual components are examined. The latter include design-oriented analysis, approximation concepts, mathematical system modeling, design space search, an optimization procedure, and a humane interface.

  15. Discourses of Conflict: A Multidisciplinary Study of Professional Education.

    ERIC Educational Resources Information Center

    Phelan, Anne M.; Barlow, Constance; Myrick, Florence; Rogers, Gayla; Sawa, Russell

    2003-01-01

    A 3-year study will examine conflict in professional field education. Stage 1 will collect narratives about critical incidents from student-field instructor-faculty member triads in the fields of education, medicine, nursing, and social work. Stage 2 will focus on analysis of narratives. Stage 3 will include multidisciplinary conversations among…

  16. How Multidisciplinary Are the Multidisciplinary Journals Science and Nature?

    PubMed Central

    Solomon, Gregg E. A.; Carley, Stephen; Porter, Alan L.

    2016-01-01

    Interest in cross-disciplinary research knowledge interchange runs high. Review processes at funding agencies, such as the U.S. National Science Foundation, consider plans to disseminate research across disciplinary bounds. Publication in the leading multidisciplinary journals, Nature and Science, may signify the epitome of successful interdisciplinary integration of research knowledge and cross-disciplinary dissemination of findings. But how interdisciplinary are they? The journals are multidisciplinary, but do the individual articles themselves draw upon multiple fields of knowledge and does their influence span disciplines? This research compares articles in three fields (Cell Biology, Physical Chemistry, and Cognitive Science) published in a leading disciplinary journal in each field to those published in Nature and Science. We find comparable degrees of interdisciplinary integration and only modest differences in cross-disciplinary diffusion. That said, though the rate of out-of-field diffusion might be comparable, the sheer reach of Nature and Science, indicated by their potent Journal Impact Factors, means that the diffusion of knowledge therein can far exceed that of leading disciplinary journals in some fields (such as Physical Chemistry and Cognitive Science in our samples). PMID:27043924

  17. How Multidisciplinary Are the Multidisciplinary Journals Science and Nature?

    PubMed

    Solomon, Gregg E A; Carley, Stephen; Porter, Alan L

    2016-01-01

    Interest in cross-disciplinary research knowledge interchange runs high. Review processes at funding agencies, such as the U.S. National Science Foundation, consider plans to disseminate research across disciplinary bounds. Publication in the leading multidisciplinary journals, Nature and Science, may signify the epitome of successful interdisciplinary integration of research knowledge and cross-disciplinary dissemination of findings. But how interdisciplinary are they? The journals are multidisciplinary, but do the individual articles themselves draw upon multiple fields of knowledge and does their influence span disciplines? This research compares articles in three fields (Cell Biology, Physical Chemistry, and Cognitive Science) published in a leading disciplinary journal in each field to those published in Nature and Science. We find comparable degrees of interdisciplinary integration and only modest differences in cross-disciplinary diffusion. That said, though the rate of out-of-field diffusion might be comparable, the sheer reach of Nature and Science, indicated by their potent Journal Impact Factors, means that the diffusion of knowledge therein can far exceed that of leading disciplinary journals in some fields (such as Physical Chemistry and Cognitive Science in our samples).

  18. Bay of Bengal: coupling of pre-monsoon tropical cyclones with the monsoon onset in Myanmar

    NASA Astrophysics Data System (ADS)

    Fosu, Boniface O.; Wang, Shih-Yu Simon

    2015-08-01

    The pre-monsoon tropical cyclone (TC) activity and the monsoon evolution in the Bay of Bengal (BoB) are both influenced by the Madden-Julian Oscillation (MJO), but the two do not always occur in unison. This study examines the conditions that allow the MJO to modulate the monsoon onset in Myanmar and TC activity concurrently. Using the APHRODITE gridded precipitation and the ERA-Interim reanalysis datasets, composite evolutions of monsoon rainfall and TC genesis are constructed for the period of 1979-2010. It is found that the MJO exhibits a strong interannual variability in terms of phase and intensity, which in some years modulate the conditions for BoB TCs to shortly precede or form concurrently with the monsoon onset in Myanmar. Such a modulation is absent in years of weaker MJO events. Further understanding of the interannual variability of MJO activity could facilitate the prediction of the monsoon onset and TC formation in the BoB.

  19. Comment on "Large volcanic aerosol load in the stratosphere linked to Asian monsoon transport".

    PubMed

    Vernier, J-P; Thomason, L W; Fairlie, T D; Minnis, P; Palikonda, R; Bedka, K M

    2013-02-08

    Bourassa et al. (Reports, 6 July 2012, p. 78) have suggested that deep convection associated with the Asian monsoon played a critical role in transporting sulfur dioxide associated with the Nabro volcanic eruption (13 June 2011) from the upper troposphere (9 to 14 kilometers) into the lower stratosphere. An analysis of the CALIPSO lidar data indicates, however, that the main part of the Nabro volcanic plume was injected directly into the lower stratosphere during the initial eruption well before reaching the Asian monsoon deep convective region.

  20. [Multidisciplinary therapy of colorectal cancer].

    PubMed

    Balogh, A; Kahán, Z; Maráz, A; Mikó, T; Nagy, F; Palkó, A; Thurzó, L; Tiszlavicz, L

    2001-03-18

    A multidisciplinary program for the treatment of colorectal cancer is described. The main objective of the authors has been to define uniform up to date guidelines based on recent progress in the treatment of colorectal cancer. Preoperative diagnostic procedures are summarized which advance determination of clinical stage and prognosis. These information essentially determine care. Sequences of surgical methods, preoperative and postoperative radiotherapy and medical treatments are discussed according to tumor stages. Guidelines for surveillance following active treatment and recommendation for the screening of population at high risk for colorectal cancer are presented.

  1. Land-Climate Feedbacks in Indian Summer Monsoon Rainfall

    NASA Astrophysics Data System (ADS)

    Asharaf, Shakeel; Ahrens, Bodo

    2016-04-01

    In an attempt to identify how land surface states such as soil moisture influence the monsoonal precipitation climate over India, a series of numerical simulations including soil moisture sensitivity experiments was performed. The simulations were conducted with a nonhydrostatic regional climate model (RCM), the Consortium for Small-Scale Modeling (COSMO) in climate mode (CCLM) model, which was driven by the European Center for Medium-Range Weather Forecasts (ECMWF) Interim reanalysis (ERA-Interim) data. Results showed that pre-monsoonal soil moisture has a significant impact on monsoonal precipitation formation and large-scale atmospheric circulations. The analysis revealed that even a small change in the processes that influence precipitation via changes in local evapotranspiration was able to trigger significant variations in regional soil moisture-precipitation feedback. It was observed that these processes varied spatially from humid to arid regions in India, which further motivated an examination of soil-moisture memory variation over these regions and determination of the ISM seasonal forecasting potential. A quantitative analysis indicated that the simulated soil-moisture memory lengths increased with soil depth and were longer in the western region than those in the eastern region of India. Additionally, the subsequent precipitation variance explained by soil moisture increased from east to west. The ISM rainfall was further analyzed in two different greenhouse gas emission scenarios: the Special Report on Emissions Scenario (SRES: B1) and the new Representative Concentration Pathways (RCPs: RCP4.5). To that end, the CCLM and its driving global-coupled atmospheric-oceanic model (GCM), ECHAM/MPIOM were used in order to understand the driving processes of the projected inter-annual precipitation variability and associated trends. Results inferred that the projected rainfall changes were the result of two largely compensating processes: increase of remotely

  2. The MONSOON Generic Pixel Server software design

    NASA Astrophysics Data System (ADS)

    Buchholz, Nick C.; Daly, Philip N.

    2004-09-01

    MONSOON is the next generation OUV-IR controller development project being conducted at NOAO. MONSOON was designed from the start as an "architecture" that provides the flexibility to handle multiple detector types, rather than as a set of specific hardware to control a particular detector. The hardware design was done with maintainability and scalability as key factors. We have, wherever possible chosen commercial off-the-shelf components rather than use in-house or proprietary systems. From first principles, the software design had to be configurable in order to handle many detector types and focal plane configurations. The MONSOON software is multi-layered with simulation of the hardware built in. By keeping the details of hardware interfaces confined to only two libraries and by strict conformance to a set of interface control documents the MONSOON software is usable with other hardware systems with minimal change. In addition, the design provides that focal plane specific details are confined to routines that are selected at load time. At the top-level, the MONSOON Supervisor Level (MSL), we use the GPX dictionary, a defined interface to the software system that instruments and high-level software can use to control and query the system. Below this are PAN-DHE pairs that interface directly with portions of the focal plane. The number of PAN-DHE pairs can be scaled up to increase channel counts and processing speed or to handle larger focal planes. The range of detector applications supported goes from single detector LAB systems, four detector IR systems like NEWFIRM, up to 500 CCD focal planes like LSST. In this paper we discuss the design of the PAN software and it's interaction with the detector head electronics.

  3. Energetic constraints on monsoonal Hadley circulations

    NASA Astrophysics Data System (ADS)

    Merlis, T. M.; Schneider, T.; Bordoni, S.; Eisenman, I.

    2011-12-01

    The strength of monsoons is believed to have varied in the past in response to changes in the seasonal shortwave radiation distribution associated with orbital precession and is expected to vary during the coming century due to increases in greenhouse gas concentrations. Here, we examine the constraint that the moist static energy budget imposes on the response to radiative perturbations of the cross-equatorial, or monsoonal, Hadley circulations. Changes in the strength of the mass transport can occur in response to radiative perturbations, which has been frequently discussed in the past. An additional factor in the energetic balance, however, is the atmosphere's energy stratification, which is commonly known as the gross moist stability in tropical meteorology. Therefore, changes in the atmosphere's gross moist stability can play a fundamental role in determining changes in the mass transport of mean circulations. Also, the influence of spatial variations in surface heat capacity on the top-of-the-atmosphere energy balance, rather than its widely discussed role in determining surface temperature, is important in determining how radiative perturbations are energetically balanced by monsoonal Hadley circulations. We examine the importance of energetic constraints on monsoonal Hadley circulations in idealized general circulation model simulations that have either an aquaplanet slab-ocean boundary condition or a zonally symmetric subtropical continent. The radiative balance in the simulations is perturbed first by insolation variations associated with orbital precession and then by increased carbon dioxide concentration. The simulation results demonstrate that summertime changes in gross moist stability are important for understanding past and future monsoon variations.

  4. The Monsoon as a Self-regulating Coupled Ocean-Atmosphere System

    NASA Astrophysics Data System (ADS)

    Webster, P. J.; Clark, C.; Cherikova, G.; Fasullo, J.; Han, W.; Loschnigg, J.; Sahami, K.

    INTRODUCTION REGULATION OF THE MONSOON ANNUAL CYCLE The Climatological Annual Cycle Processes Determining the Annual Cycle of the Monsoon Role of Ocean Dynamics in the Annual Heat Balance of the Indian - Ocean Regulation of the Annual Cycle of the Monsoon: an Ocean-Atmosphere - Feedback System INTERANNUAL VARIABILITY OF THE MONSOON Modes of Interannual Variability in the Monsoon Interannual Modes in Ocean Heat Transport Interannual Regulation of the Monsoon GENERAL THEORY OF REGULATION OF THE COUPLED OCEAN-ATMOSPHERIC MONSOON - SYSTEM CONCLUSIONS REFERENCES

  5. Oncoplastic multidisciplinary meetings: a necessity or luxury?

    PubMed

    Rusby, Jennifer E; Gough, Jenny; Harris, Paul A; MacNeill, Fiona A

    2011-05-01

    Although there is scant evidence to support multidisciplinary meetings in any cancer specialty, they are now regarded as best practice. We believe the oncoplastic multidisciplinary meeting plays a similarly important role, consolidating oncoplastic multidisciplinary working and allowing transparent decision making, standardisation of care and recording of results. This may drive oncoplastic surgery to an evidence-based position from which oncoplastic excellence can be achieved.

  6. East Asian monsoon signals reflected in temperature and precipitation changes over the past 300 years in the middle and lower reaches of the Yangtze River.

    PubMed

    Hao, Zhixin; Sun, Di; Zheng, Jingyun

    2015-01-01

    Based on observational data and Asian monsoon intensity datasets from China, the relationships between the East Asian winter monsoon index and winter temperature, the East Asian summer monsoon index and Meiyu precipitation over the middle and lower reaches of the Yangtze River, were analyzed. We found that the monsoon signals were reflected in the temperature and Meiyu precipitation variations. Thus, we used the reconstructed Meiyu precipitation and winter temperature series for the past 300 years and detected the summer/winter monsoon intensity signals using multi-taper spectral estimation method and wavelet analysis. The main periodicities of Meiyu precipitation and winter temperature, such as interannual cycle with 2-7-year, interdecadal-centennial cycles with 30-40-year and 50-100-year, were found. The good relationships between the East Asian summer and winter monsoons suggested that they were in phase at 31-year cycle, while out of phase at 100-year cycle, but with 20-year phase difference. In addition, the winter monsoon intensity may be regulated by the North Atlantic Oscillation, the Arctic Oscillation and the Atlantic Multidecadal Oscillation, and the summer monsoon is closely related to the signal intensities of the Pacific Decadal Oscillation.

  7. East Asian Monsoon Signals Reflected in Temperature and Precipitation Changes over the Past 300 Years in the Middle and Lower Reaches of the Yangtze River

    PubMed Central

    Hao, Zhixin; Sun, Di; Zheng, Jingyun

    2015-01-01

    Based on observational data and Asian monsoon intensity datasets from China, the relationships between the East Asian winter monsoon index and winter temperature, the East Asian summer monsoon index and Meiyu precipitation over the middle and lower reaches of the Yangtze River, were analyzed. We found that the monsoon signals were reflected in the temperature and Meiyu precipitation variations. Thus, we used the reconstructed Meiyu precipitation and winter temperature series for the past 300 years and detected the summer/winter monsoon intensity signals using multi-taper spectral estimation method and wavelet analysis. The main periodicities of Meiyu precipitation and winter temperature, such as interannual cycle with 2–7-year, interdecadal-centennial cycles with 30–40-year and 50–100-year, were found. The good relationships between the East Asian summer and winter monsoons suggested that they were in phase at 31-year cycle, while out of phase at 100-year cycle, but with 20-year phase difference. In addition, the winter monsoon intensity may be regulated by the North Atlantic Oscillation, the Arctic Oscillation and the Atlantic Multidecadal Oscillation, and the summer monsoon is closely related to the signal intensities of the Pacific Decadal Oscillation. PMID:26107375

  8. South Asian Summer Monsoon and Its Relationship with ENSO in the IPCC AR4 Simulations

    SciTech Connect

    Annamalai, H; Hamilton, K; Sperber, K R

    2005-09-07

    In this paper we use the extensive integrations produced for the IPCC Fourth Assessment Report (AR4) to examine the relationship between ENSO and the monsoon at interannual and decadal timescales. We begin with an analysis of the monsoon simulation in the 20th century integrations. Six of the 18 models were found to have a reasonably realistic representation of monsoon precipitation climatology. For each of these six models SST and anomalous precipitation evolution along the equatorial Pacific during El Nino events display considerable differences when compared to observations. Out of these six models only four (GFDL{_}CM{_}2.0, GFDL{_}CM{_}2.1, MRI, and MPI{_}ECHAM5) exhibit a robust ENSO-monsoon contemporaneous teleconnection, including the known inverse relationship between ENSO and rainfall variations over India. Lagged correlations between the all-India rainfall (AIR) index and Nino3.4 SST reveal that three models represent the timing of the teleconnection, including the spring predictability barrier which is manifested as the transition from positive to negative correlations prior to the monsoon onset. Furthermore, only one of these three models (GFDL{_}CM{_}2.1) captures the observed phase lag with the strongest anticorrelation of SST peaking 2-3 months after the summer monsoon, which is partially attributable to the intensity of simulated El Nino itself. We find that the models that best capture the ENSO-monsoon teleconnection are those that correctly simulate the timing and location of SST and diabatic heating anomalies in the equatorial Pacific, and the associated changes to the equatorial Walker Circulation during El Nino events. The strength of the AIR-Nino3.4 SST correlation in the model runs waxes and wanes to some degree on decadal timescales. The overall magnitude and timescale for this decadal modulation in most of the models is similar to that seen in observations. However, there is little consistency in the phase among the realizations

  9. Dirtier Air from a Weaker Monsoon

    NASA Technical Reports Server (NTRS)

    Chin, Mian

    2012-01-01

    The level of air pollution in China has much increased in the past decades, causing serious health problems. Among the main pollutants are aerosols, also known as particulate matter: tiny, invisible particles that are suspended in the air. These particles contribute substantially to premature mortality associated with cardiopulmonary diseases and lung cancer1. The increase of the aerosol level in China has been commonly attributed to the fast rise in pollutant emissions from the rapid economic development in the region. However, writing in Geophysical Research Letters, Jianlei Zhu and colleagues2 tell a different side of the story: using a chemical transport model and observation data, they show that the decadal scale weakening of the East Asian summer monsoon has also contributed to the increase of aerosol concentrations in China. The life cycle of atmospheric aerosols starts with its emission or formation in the atmosphere. Some aerosol components such as dust, soot and sea salt are emitted directly as particles to the atmosphere, but others are formed there by way of photochemical reactions. For example, sulphate and nitrate aerosols are produced from their respective precursor gases, sulphur dioxide and nitrogen oxides. Aerosol particles can be transported away from their source locations by winds or vertical motion of the air. Eventually, they are removed from the atmosphere by means of dry deposition and wet scavenging by precipitation. Measurements generally show that aerosol concentrations over Asia are lowest during the summer monsoon season3, because intense rainfall efficiently removes them from the air. The East Asian summer monsoon extends over subtropics and mid-latitudes. Its rainfall tends to concentrate in rain belts that stretch out for many thousands of kilometres and affect China, Korea, Japan and the surrounding area. Observations suggest that the East Asian summer monsoon circulation and precipitation have been in decline since the 1970s4. In

  10. Evolving the linkages between North American Monsoon Experiment research and services in the binational monsoon region

    NASA Astrophysics Data System (ADS)

    Ray, A. J.

    2007-05-01

    Multi-year drought, high interannual precipitation variability, and rapid population growth present major challenges to water resources and land managers in the U.S. Southwest and binational monsoon region. The NAME strategy to improve warm season precipitation forecasts is paying off in the understanding of the system and its potential predictability, illustrated by a special issue of the Journal of Climate with about 25 articles and numerous other published papers (e.g. Higgins and Gochis et al. 2006; Gutzler et al. 2004, Higgins et al. 2003). NOAA now has set a goal to NAME and other initiatives also have the potential to provide key insights, such as historic information regarding onset and overall strength of the monsoon as it affects stakeholder interests in flooding, soil moisture, vegetation health, and summer water demand. However, the usual avenues for scientific output, such as peer-reviewed publications and web sites designed for use by climate and weather experts, do not adequately support the flow of knowledge to operational decisionmakers. A recent workshop on Monsoon Region climate Applications in Guaymas, Sonora identified several areas in which monsoon science might contribute to reducing societal vulnerability, as well as some research findings that are suited to transition into model development and operations at service providers including NOAA and SMN. They recommended that products are needed that interpret climate forecasts for water resource management applications, and developing new regionally-tailored climate information products. This presentation will discuss how to enhance the flow of monsoon information and predictions to stakeholders by linking user-oriented perspectives with research results from NAME and other programs, including a new effort for a North American Monsoon Forecast Forum which plans to develop periodic consolidated North American Monsoon outlooks.

  11. Atmospheric circulation processes contributing to a multidecadal variation in reconstructed and modeled Indian monsoon precipitation

    NASA Astrophysics Data System (ADS)

    Wu, Qianru; Hu, Qi

    2015-01-01

    analysis of the recently reconstructed gridded May-September total precipitation in the Indian monsoon region for the past half millennium discloses significant variations at multidecadal timescales. Meanwhile, paleo-climate modeling outputs from the National Center for Atmospheric Research Community Climate System Model 4.0 show similar multidecadal variations in the monsoon precipitation. One of those variations at the frequency of 40-50 years per cycle is examined in this study. Major results show that this variation is a product of the processes in that the meridional gradient of the atmospheric enthalpy is strengthened by radiation loss in the high-latitude and polar region. Driven by this gradient and associated baroclinicity in the atmosphere, more heat/energy is generated in the tropical and subtropical (monsoon) region and transported poleward. This transport relaxes the meridional enthalpy gradient and, subsequently, the need for heat production in the monsoon region. The multidecadal timescale of these processes results from atmospheric circulation-radiation interactions and the inefficiency in generation of kinetic energy from the potential energy in the atmosphere to drive the eddies that transport heat poleward. This inefficiency creates a time delay between the meridional gradient of the enthalpy and the poleward transport. The monsoon precipitation variation lags that in the meridional gradient of enthalpy but leads that of the poleward heat transport. This phase relationship, and underlining chasing process by the transport of heat to the need for it driven by the meridional enthalpy gradient, sustains this multidecadal variation. This mechanism suggests that atmospheric circulation processes can contribute to multidecadal timescale variations. Interactions of these processes with other forcing, such as sea surface temperature or solar irradiance anomalies, can result in resonant or suppressed variations in the Indian monsoon precipitation.

  12. POPULATION DYNAMICS OF GREEN NOCTILUCA SCINTILLANS (DINOPHYCEAE) ASSOCIATED WITH THE MONSOON CYCLE IN THE UPPER GULF OF THAILAND(1).

    PubMed

    Sriwoon, Rujinard; Pholpunthin, Pornsilp; Lirdwitayaprasit, Thaithaworn; Kishino, Motoaki; Furuya, Ken

    2008-06-01

    Population dynamics of Noctiluca scintillans (Macartney) Kof. et Swezy containing the photosynthetic endosymbiont Pedinomonas noctilucae (Subrahman.) Sweeney was investigated in relation to environmental conditions in the upper Gulf of Thailand. A clear association was observed between the abundance of N. scintillans and the monsoon cycle, with its blooms occurring during the southwest (SW) monsoon from May to September, and low abundance during the northeast (NE) monsoon from November to February. Nutrient concentrations were higher during the SW monsoon than during the NE monsoon due to the combined effect of increased river discharge into the northern upper gulf and the transport of the riverine inputs by the prevailing clockwise circulation of the water. These nutrient conditions favored the growth of both phytoplankton and the endosymbiont. Correlation analysis revealed that the higher abundance of N. scintillans in the SW monsoon was manifested primarily by higher growth through both sexual and asexual reproduction supported by phagotrophy. However, the dependence of N. scintillans on the nutrient concentration was not significant, probably because the nutrient supply for the endosymbiont was sufficient due to intracellular accumulation of nutrients within the host cells. Sexual reproduction occurred only during the SW monsoon, and its potential importance in population growth was suggested. These findings showed the bottom-up control of the population dynamics of N. scintillans through growth of phytoplankton as prey. The seasonal shift in the circulation pattern associated with the monsoon cycle played a crucial role in blooming of N. scintillans by producing favorable food conditions.

  13. The Diurnal Cycle of the Boundary Layer, Convection, Clouds, and Surface Radiation in a Coastal Monsoon Environment (Darwin Australia)

    SciTech Connect

    May, Peter T.; Long, Charles N.; Protat, Alain

    2012-08-01

    The diurnal variation of convection and associated cloud and radiative properties remains a significant issue in global NWP and climate models. This study analyzes observed diurnal variability of convection in a coastal monsoonal environment examining the interaction of convective rain clouds, their associated cloud properties, and the impact on the surface radiation and corresponding boundary layer structure during periods where convection is suppressed or active on the large scale. The analysis uses data from the Tropical Warm Pool International Cloud Experiment (TWP-ICE) as well as routine measurements from the Australian Bureau of Meteorology and the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) program. Both active monsoonal and large-scale suppressed (buildup and break) conditions are examined and demonstrate that the diurnal variation of rainfall is much larger during the break periods and the spatial distribution of rainfall is very different between the monsoon and break regimes. During the active monsoon the total net radiative input to the surface is decreased by more than 3 times the amount than during the break regime - this total radiative cloud forcing is found to be dominated by the shortwave (SW) cloud effects because of the much larger optical thicknesses and persistence of long-lasting anvils and cirrus cloud decks associated with the monsoon regime. These differences in monsoon versus break surface radiative energy contribute to low-level air temperature differences in the boundary layer over the land surfaces.

  14. Effect of El-Nino on Southwest Monsoon 2015

    NASA Astrophysics Data System (ADS)

    K. U., Vidhulakshmi; Mrudula, G.

    2016-05-01

    Indian Summer Monsoon Rainfall (ISMR) of 2015 showed a deficit of 14% in the seasonal rainfall. Many researchers connected this deficit to the El-Nino which developed in late May. In this study an analysis of major ENSO events and its influence on ISMR during the period 1975 till present have been carried out. The behavior of ISMR during the previous El-Nino/La-Nina years has been compared with that of 2015. Preliminary analysis shows the effects of El-Nino on ISMR of 2015 started mainly from July. This is attributed to Madden Julian Oscillation (MJO) by many scientists. Analysis of spatial and temporal correlations of SST of various Nino regions with the ISMR and of MJO will also be presented in detail.

  15. A Comparison of Pre-monsoonal and Monsoonal Radiative Forcing by Anthropogenic Aerosols over South Asia

    NASA Astrophysics Data System (ADS)

    Lee, S.; Cohen, J. B.; Wang, C.

    2012-12-01

    Radiative forcing by anthropogenic aerosols after monsoon onset is often considered unimportant compared to forcing during the pre-monsoonal period, due to precipitation scavenging. We tested this assumption for the South Asian monsoon using three model runs with forcing prescribed during the pre-monsoonal period (March-May), monsoon period (June-September) and both periods. The forcing represents the direct radiative effects of sulfate, organic carbon and black carbon. It was derived from a set of Kalman filter-optimised black carbon emissions from a modelling system based on the CAM3 GCM, a two-moment multi-scheme aerosol and radiation model, and a coupled urban scale processing package; we expect it to be reliable within its given error bounds. The monthly climatological forcing values were prescribed over South Asia every year for 100 years to CESM 1.0.4, a coupled atmosphere-ocean model. We shall compare the three resultant climatologies with climatologies from a no aerosol model and a full aerosol model.

  16. Earlier North American Monsoon Onset in a Warmer World?

    NASA Astrophysics Data System (ADS)

    Rauscher, S. A.; Seth, A.; Ringler, T.; Rojas, M.; Liebmann, B.

    2009-12-01

    Analysis of twenty-first century projections indicate substantial drying over the American Southwest and the potential for “Dust Bowl” conditions to be the norm by the middle of century. Closer examination of monthly precipitation data from the CMIP3 models indicates that the annual cycle is actually amplified over the North American Monsoon (NAMS) region, with drier conditions during the winter and an increase in monsoon rains during the later part of the rainy season. Importantly, the projected decrease in winter precipitation extends into the spring season, suggesting a delayed onset of the NAMS. Consistent thermodynamic changes, including a decrease in low-level relative humidity and an increase in the vertical gradient of moist static energy, accompany this spring precipitation decrease. Here we examine daily precipitation data from the CMIP3 archive to determine if this reduced spring precipitation represents a true delay in the NAMS onset. We further analyze the hydrological cycle over the NAMS region in several of the CMIP3 models, focusing on changes in net moisture divergence, surface evaporation, and soil moisture in order to fully understand how the hydrological cycle will change in the future based on the CMIP3 simulations, and how these changes may be translated into the timing and intensity of the NAMS. The combination of a delayed NAMS onset and earlier and reduced snowmelt runoff in the western US could substantially change the availability of water resources over the NAMS region.

  17. [Multidisciplinary treatment of orofacial pain].

    PubMed

    Geurts, J W; Haumann, J; van Kleef, M

    2016-11-01

    The diagnosis and treatment of orofacial pain can be complex. The differential diagnosis is very extensive. Therefore, multidisciplinary diagnosis and treatment are often indicated. The diagnosis of chronic pain also entails the investigation of psychological factors. This is because psychological problems can play a role in the chronification of pain, but they can also be a consequence of chronic pain. Patients with persistent orofacial complaints should be seen by a medical team consisting of an oral and maxillofacial surgeon, a neurologist, an anaesthesiologist/pain specialist, a dentist-gnathologist, an orofacial physical therapist, and a psychologist or psychiatrist specialising in orofacial pain. Treatment options should be discussed, taking into account literature concerning their effectiveness. The general conclusion is that much research remains to be done into the causes of, and treatments for, orofacial pain.

  18. Integration of Multidisciplinary Sensory Data:

    PubMed Central

    Miller, Perry L.; Nadkarni, Prakash; Singer, Michael; Marenco, Luis; Hines, Michael; Shepherd, Gordon

    2001-01-01

    The paper provides an overview of neuroinformatics research at Yale University being performed as part of the national Human Brain Project. This research is exploring the integration of multidisciplinary sensory data, using the olfactory system as a model domain. The neuroinformatics activities fall into three main areas: 1) building databases and related tools that support experimental olfactory research at Yale and can also serve as resources for the field as a whole, 2) using computer models (molecular models and neuronal models) to help understand data being collected experimentally and to help guide further laboratory experiments, 3) performing basic neuroinformatics research to develop new informatics technologies, including a flexible data model (EAV/CR, entity-attribute-value with classes and relationships) designed to facilitate the integration of diverse heterogeneous data within a single unifying framework. PMID:11141511

  19. [Multidisciplinary practice guideline 'Marfan syndrome'].

    PubMed

    Hilhorst-Hofstee, Yvonne

    2013-01-01

    Marfan syndrome is a multi-system disorder of dominant inheritance in which the cardiovasculature, in particular the aorta, the eyes and the skeleton are affected. Diagnostic assessment and treatment of patients who are suspected of or have Marfan syndrome should preferably be done by multidisciplinary teams such as those found in specialised Marfan syndrome centres. The practice guideline is intended for all care givers involved with the recognition, diagnosis, consultations and the medicinal and surgical treatment of Marfan patients; it includes referral criteria and information on the referral process. A diagnosis of Marfan syndrome is based on international criteria in which aortic root dilatation and dissection, ectopia lentis, an affected first-degree family member and a pathogenic FBN1 mutation are the cardinal features. Alternative diagnoses are also included in the practice guideline. Recommendations are given for the monitoring and treatment of Marfan patients during pregnancy and delivery. Advice on lifestyle is mainly focussed on sports activities.

  20. [Wilms' tumor. Its multidisciplinary management].

    PubMed

    Rivera Luna, R; Martínez Guerra, G; Ruano Aguilar, J; Cárdenas Cardoz, R; Lanche Guevara, T

    1992-01-01

    A total of 115 children with a histopathological diagnosis of Wilms' tumor were studied. The average age was three years. An abdominal tumor was the most frequent clinical manifestations, with a predominating clinicopathological stage II. The most important prognostic factors were the clinical stage and histological subvariety. A five year disease free period during the early stages was very favorable. On the other hand, advances stages and unfavorable histopathology established a poor prognosis. In our experience, stages I and II and favorable histology should not receive radiotherapy but instead brief chemotherapy. The global five year survival was 82%. All the patients with an unfavorable histology occupied stages II and IV. a comparison of disease free survival between stages I and II against III and IV showed statistical significance (p 0.01). Statistical significance also appeared upon comparison between unfavorable versus favorable (p 0.01) histology. Emphasis is placed upon multidisciplinary management of this type of malignant neoplasias.

  1. Multidisciplinary survey of erectile impotence.

    PubMed Central

    Collins, W. E.; McKendry, J. B.; Silverman, M.; Krul, L. E.; Collins, J. P.; Irvine, A. H.

    1983-01-01

    A study was done of 220 men referred principally by family physicians to a multidisciplinary erectile dysfunction study group to determine the factors causing or contributing to impotence that had persisted for more than 2 months and for which no cause was apparent. The men were aged 21 to 79 (mean 50.3) years, and the duration of impotence was a few months to 15 years (mean 2.65 years). The men were to be assessed from general medical, endocrinologic/metabolic, psychiatric and urogenital viewpoints. The significance of the causal or contributory factors detected was scored by application of defined criteria and a four-point scale. The degree of loss of potency and of libido as well as level of concern were also scored by each specialist. Impotence was complete in 60%, and an associated decline in libido was reported by 38%. The level of concern was high--that is, normal--in 81% and slightly reduced in 9%. Full investigation by all the specialists was precluded by the severity of other conditions in 16 patients, by the return of potency following relief of anxiety/depression or genitourinary tract infection in 16 and for logistic or other reasons in 34. Although the cause of the impotence could be attributed in 186 of the patients, only 154 were fully assessed. Among these patients general medical factors were contributory in 46%, endocrinologic/metabolic factors in 44%, psychogenic factors (primary or secondary) in 60% and urogenital factors in 49%. Multiple contributing factors were identified in 65%, which underscores the importance of a multidisciplinary approach to assessing many cases of impotence. PMID:6850465

  2. Multi-Disciplinary Consumer Education Curriculum.

    ERIC Educational Resources Information Center

    Sie, Maureen A.; And Others

    Two activities are described in this report, both of which focus on the multi-disciplinary approach in the development of a consumer education curriculum for high school students. The first activity, which demonstrated the feasibility of a multi-disciplinary approach using local school personnel and resources and university faculty in curriculum…

  3. The Misnomer of East Asia Summer Monsoon

    NASA Technical Reports Server (NTRS)

    Chao, Winston C.; Chen, Baode

    2004-01-01

    The terminology East Asian summer monsoon is used to refer to the heavy rainfall in southeast China including the Yangtze River Valley starting in May and ending in August (e.g., Chen and Chang 1980, Tao and Chen 1987, Ding 1992, Chang et al. 2000a.) This rainfall region is associated with the Mei-Yu front, which extends to Japan and its neighborhood and is called Baiu there. The Mei-Yu front becomes prominent in May and has a slow northward movement. From May to July the elongated rain belt moves from the southeast coast of China to the Yangtze River Valley. The rain belt extends north-east-ward to south of Japan in May and later covers Korea also. The purpose of this note is to point out that the terminology of East Asian summer monsoon is a misnomer to refer to the portion of this rainbelt residing over East Asia, in the sense that it is not a monsoon.

  4. Potential Change in the Indian Monsoon Circulation

    NASA Astrophysics Data System (ADS)

    Funk, C. C.; Williams, A. P.; Mishra, V.; Barlow, M. A.; Hoerling, M. P.; Hoell, A.

    2011-12-01

    In India and East Africa more than 350 million people face chronic undernourishment; population growth alone could bring this number to 500 million by 2030. Below normal rains have become more frequent as falling water tables, land degradation, warmer air temperatures, and rising fuel and fertilizer costs limit crop production growth. The Indian and East African boreal summer monsoons rely on large moisture transports from the southern Indian Ocean (SIO, 55-90°E, 0-15°S) and a low pressure cell over the north Indian Ocean (NIO, 55-90°E, 0-15°N). The relatively cloud free NIO warm pool receives a large excess of solar radiation, which the ocean transports south across the equator. While many factors influence this system, we present here observations and climate simulations linking preferential SIO-versus-NIO warming, evaporation and precipitation changes to weaker monsoon winds, weaker northward moisture transports, and warmer and drier weather in India and East Africa. Observations show that increasing SIO sea surface temperatures (SSTs) below rapid surface winds provide an 'evaporative window' (Fig. 1) that transfers energy and moisture to the atmosphere, increasing SIO rainfall. Climate simulations driven with i) observed SSTs and ii) mid-tropospheric SIO heating associate increased SIO rainfall with lower NIO rainfall. Given the empirical relationships between increasing SIO rainfall and reduced summer monsoon rains, continued warming in the Indian Ocean could lead to more frequent droughts in India, and perhaps, East Africa.

  5. A multidisciplinary conceptualization of conservation opportunity.

    PubMed

    Moon, Katie; Adams, Vanessa M; Januchowski-Hartley, Stephanie R; Polyakov, Maksym; Mills, Morena; Biggs, Duan; Knight, Andrew T; Game, Edward T; Raymond, Christopher M

    2014-12-01

    An opportunity represents an advantageous combination of circumstances that allows goals to be achieved. We reviewed the nature of opportunity and how it manifests in different subsystems (e.g., biophysical, social, political, economic) as conceptualized in other bodies of literature, including behavior, adoption, entrepreneur, public policy, and resilience literature. We then developed a multidisciplinary conceptualization of conservation opportunity. We identified 3 types of conservation opportunity: potential, actors remove barriers to problem solving by identifying the capabilities within the system that can be manipulated to create support for conservation action; traction, actors identify windows of opportunity that arise from exogenous shocks, events, or changes that remove barriers to solving problems; and existing, everything is in place for conservation action (i.e., no barriers exist) and an actor takes advantage of the existing circumstances to solve problems. Different leverage points characterize each type of opportunity. Thus, unique stages of opportunity identification or creation and exploitation exist: characterizing the system and defining problems; identifying potential solutions; assessing the feasibility of solutions; identifying or creating opportunities; and taking advantage of opportunities. These stages can be undertaken independently or as part of a situational analysis and typically comprise the first stage, but they can also be conducted iteratively throughout a conservation planning process. Four types of entrepreneur can be identified (business, policy, social, and conservation), each possessing attributes that enable them to identify or create opportunities and take advantage of them. We examined how different types of conservation opportunity manifest in a social-ecological system (the Great Barrier Reef) and how they can be taken advantage of. Our multidisciplinary conceptualization of conservation opportunity strengthens and

  6. Asian monsoon failure and megadrought during the last millennium.

    PubMed

    Cook, Edward R; Anchukaitis, Kevin J; Buckley, Brendan M; D'Arrigo, Rosanne D; Jacoby, Gordon C; Wright, William E

    2010-04-23

    The Asian monsoon system affects more than half of humanity worldwide, yet the dynamical processes that govern its complex spatiotemporal variability are not sufficiently understood to model and predict its behavior, due in part to inadequate long-term climate observations. Here we present the Monsoon Asia Drought Atlas (MADA), a seasonally resolved gridded spatial reconstruction of Asian monsoon drought and pluvials over the past millennium, derived from a network of tree-ring chronologies. MADA provides the spatiotemporal details of known historic monsoon failures and reveals the occurrence, severity, and fingerprint of previously unknown monsoon megadroughts and their close linkages to large-scale patterns of tropical Indo-Pacific sea surface temperatures. MADA thus provides a long-term context for recent monsoon variability that is critically needed for climate modeling, prediction, and attribution.

  7. Intraseasonal Variability of the Low-Level Jet Stream of the Asian Summer Monsoon.

    NASA Astrophysics Data System (ADS)

    Joseph, P. V.; Sijikumar, S.

    2004-04-01

    The strong cross-equatorial low level jet stream (LLJ) with its core around 850 hPa of the Asian summer monsoon (June September) is found to have large intraseasonal variability. During the monsoon onset over Kerala, India, and during break monsoon periods, when the convective heating of the atmosphere is over the low latitudes of the Indian Ocean, the axis of the LLJ is oriented southeastward over the eastern Arabian Sea and it flows east between Sri Lanka and the equator and there is no LLJ through peninsular India. This affects the transport of moisture produced over the Indian Ocean to peninsular India and the Bay of Bengal. In contrast, during active monsoon periods when there is an east west band of strong convective heating in the latitudes 10° 20°N from about longitude 70° to about 120°E, the LLJ axis passes from the central Arabian Sea eastward through peninsular India and it provides moisture for the increased convection in the Bay of Bengal and for the monsoon depressions forming there. The LLJ does not show splitting into two branches over the Arabian Sea. Splitting of the jet was first suggested by Findlater and has since found wide acceptance as seen from the literature. Findlater's findings were based on analysis of monthly mean winds. Such an analysis is likely to show the LLJ of active and break monsoons as occurring simultaneously, suggesting a split.Strengths of the convective heat source (OLR) over the Bay of Bengal and the strength of the LLJ (zonal component of wind) at 850 hPa over peninsular India and also the Bay of Bengal between latitudes 10° and 20°N have the highest linear correlation coefficient at a lag of 2 3 days, with OLR leading. The LLJ crossing the equator close to the coast of East Africa will pass through India only if there is active monsoon convection in the latitude belt 10° 20°N over south Asia. The position in latitude of the LLJ axis between longitudes 70° and 100°E is decided by the south north movement of the

  8. Design Environment for Multifidelity and Multidisciplinary Components

    NASA Technical Reports Server (NTRS)

    Platt, Michael

    2014-01-01

    One of the greatest challenges when developing propulsion systems is predicting the interacting effects between the fluid loads, thermal loads, and structural deflection. The interactions between technical disciplines often are not fully analyzed, and the analysis in one discipline often uses a simplified representation of other disciplines as an input or boundary condition. For example, the fluid forces in an engine generate static and dynamic rotor deflection, but the forces themselves are dependent on the rotor position and its orbit. It is important to consider the interaction between the physical phenomena where the outcome of each analysis is heavily dependent on the inputs (e.g., changes in flow due to deflection, changes in deflection due to fluid forces). A rigid design process also lacks the flexibility to employ multiple levels of fidelity in the analysis of each of the components. This project developed and validated an innovative design environment that has the flexibility to simultaneously analyze multiple disciplines and multiple components with multiple levels of model fidelity. Using NASA's open-source multidisciplinary design analysis and optimization (OpenMDAO) framework, this multifaceted system will provide substantially superior capabilities to current design tools.

  9. Predicting Indian Summer Monsoon onset through variations of surface air temperature and relative humidity

    NASA Astrophysics Data System (ADS)

    Stolbova, Veronika; Surovyatkina, Elena; Kurths, Jurgen

    2015-04-01

    Indian Summer Monsoon (ISM) rainfall has an enormous effect on Indian agriculture, economy, and, as a consequence, life and prosperity of more than one billion people. Variability of the monsoonal rainfall and its onset have a huge influence on food production, agricultural planning and GDP of the country, which on 22% is determined by agriculture. Consequently, successful forecasting of the ISM onset is a big challenge and large efforts are being put into it. Here, we propose a novel approach for predictability of the ISM onset, based on critical transition theory. The ISM onset is defined as an abrupt transition from sporadious rainfall to spatially organized and temporally sustained rainfall. Taking this into account, we consider the ISM onset as is a critical transition from pre-monsoon to monsoon, which take place in time and also in space. It allows us to suggest that before the onset of ISM on the Indian subcontinent should be areas of critical behavior where indicators of the critical transitions can be detected through an analysis of observational data. First, we identify areas with such critical behavior. Second, we use detected areas as reference points for observation locations for the ISM onset prediction. Third, we derive a precursor for the ISM onset based on the analysis of surface air temperature and relative humidity variations in these reference points. Finally, we demonstrate the performance of this precursor on two observational data sets. The proposed approach allows to determine ISM onset in advance in 67% of all considered years. Our proposed approach is less effective during the anomalous years, which are associated with weak/strong monsoons, e.g. El-Nino, La-Nina or positive Indian Ocean Dipole events. The ISM onset is predicted for 23 out of 27 normal monsoon years (85%) during the past 6 decades. In the anomalous years, we show that time series analysis in both areas during the pre-monsoon period reveals indicators whether the

  10. Multidisciplinary research of geothermal modeling

    NASA Astrophysics Data System (ADS)

    -Ing. Ulvi Arslan, Univ., ., Dr. _., Prof.; Heiko Huber, Dipl.-Ing.

    2010-05-01

    KEYWORDS Geothermal sciences, geothermics, research, theory and application, numerical calculation, geothermal modeling, Technical University Darmstadt, Ministry of Economics and Technology (BMWi) INTRODUCTION In times of global warming renewable, green energies are getting more and more important. The development of application of geothermal energy as a part of renewable energies in Germany is a multidisciplinary process of fast growing research and improvements. Geothermal energy is the energy, which is stored below earth's surface. The word geothermal derives from the Greek words geo (earth) and thermos (heat), so geothermal is a synonym to earth heat. Geothermal energy is one of the auspicious renewable energies. In average the temperature increases 3°C every 100 m of depth, which is termed as geothermal gradient. Therefore 99 percent of our planet is hotter than 1.000°C, while 99 percent of that last percent is even hotter than 100°C. Already in a depth of about 1 kilometer temperatures of 35 - 40°C can be achieved. While other renewable energies arise less or more from the sun, geothermal energy sources its heat from the earth's interior, which is caused mostly by radioactive decay of persistent isotopes. This means a possibility of a base-loadable form of energy supply. Especially efficient is the use of deep geothermal energy of high-enthalpie reservoirs, which means a high energy potential in low depths. In Germany no high-enthalpie reservoirs are given. To use the given low-enthalpie potential and to generate geothermal power efficiently inventions and improvements need to be performed. An important part of geothermal progresses is performed by universities with multidisciplinary research of geothermal modeling. Especially in deep geothermal systems numerical calculations are essential for a correct dimensioning of the geothermal system. Therefore German universities and state aided organizations are developing numerical programs for a detailed use of

  11. Chemical and aerosol characterisation of the troposphere over West Africa during the monsoon period as part of AMMA

    NASA Astrophysics Data System (ADS)

    Reeves, C. E.; Formenti, P.; Afif, C.; Ancellet, G.; Attie, J.-L.; Bechara, J.; Borbon, A.; Cairo, F.; Coe, H.; Crumeyrolle, S.; Fierli, F.; Flamant, C.; Gomes, L.; Hamburger, T.; Lambert, C.; Law, K. S.; Mari, C.; Matsuki, A.; Methven, J.; Mills, G. P.; Minikin, A.; Murphy, J. G.; Nielsen, J. K.; Oram, D. E.; Parker, D. J.; Richter, A.; Schlager, H.; Schwarzenboeck, A.; Thouret, V.

    2010-03-01

    During June, July and August 2006 five aircraft took part in a campaign over West Africa to observe the aerosol content and chemical composition of the troposphere and lower stratosphere as part of the African Monsoon Multidisciplinary Analysis (AMMA) project. These are the first such measurements in this region during the monsoon period. In addition to providing an overview of the tropospheric composition, this paper provides a description of the measurement strategy (flights performed, instrumental payloads, wing-tip to wing-tip comparisons) and points to some of the important findings discussed in more detailed in other papers in this special issue. The ozone data exhibits an "S" shaped vertical profile which appears to result from significant losses in the lower troposphere due to rapid deposition to forested areas and photochemical destruction in the moist monsoon air, and convective uplift of O3-poor air to the upper troposphere. This profile is disturbed, particularly in the south of the region, by the intrusions in the lower and middle troposphere of air from the Southern Hemisphere impacted by biomass burning. Comparisons with longer term data sets suggest the impact of these intrusions on West Africa in 2006 was greater than in other recent wet seasons. There is evidence for net photochemical production of ozone in these biomass burning plumes as well as in urban plumes, in particular that from Lagos, convective outflow in the upper troposphere and in boundary layer air affected by nitrogen oxide emissions from recently wetted soils. This latter effect, along with enhanced deposition to the forested areas, contributes to a latitudinal gradient of ozone in the lower troposphere. Biogenic volatile organic compounds are also important in defining the composition both for the boundary layer and upper tropospheric convective outflow. Mineral dust was found to be the most abundant and ubiquitous aerosol type in the atmosphere over Western Africa. Data collected

  12. Chemical and aerosol characterisation of the troposphere over West Africa during the monsoon period as part of AMMA

    NASA Astrophysics Data System (ADS)

    Reeves, C. E.; Formenti, P.; Afif, C.; Ancellet, G.; Attié, J.-L.; Bechara, J.; Borbon, A.; Cairo, F.; Coe, H.; Crumeyrolle, S.; Fierli, F.; Flamant, C.; Gomes, L.; Hamburger, T.; Jambert, C.; Law, K. S.; Mari, C.; Jones, R. L.; Matsuki, A.; Mead, M. I.; Methven, J.; Mills, G. P.; Minikin, A.; Murphy, J. G.; Nielsen, J. K.; Oram, D. E.; Parker, D. J.; Richter, A.; Schlager, H.; Schwarzenboeck, A.; Thouret, V.

    2010-08-01

    During June, July and August 2006 five aircraft took part in a campaign over West Africa to observe the aerosol content and chemical composition of the troposphere and lower stratosphere as part of the African Monsoon Multidisciplinary Analysis (AMMA) project. These are the first such measurements in this region during the monsoon period. In addition to providing an overview of the tropospheric composition, this paper provides a description of the measurement strategy (flights performed, instrumental payloads, wing-tip to wing-tip comparisons) and points to some of the important findings discussed in more detail in other papers in this special issue. The ozone data exhibits an "S" shaped vertical profile which appears to result from significant losses in the lower troposphere due to rapid deposition to forested areas and photochemical destruction in the moist monsoon air, and convective uplift of ozone-poor air to the upper troposphere. This profile is disturbed, particularly in the south of the region, by the intrusions in the lower and middle troposphere of air from the southern hemisphere impacted by biomass burning. Comparisons with longer term data sets suggest the impact of these intrusions on West Africa in 2006 was greater than in other recent wet seasons. There is evidence for net photochemical production of ozone in these biomass burning plumes as well as in urban plumes, in particular that from Lagos, convective outflow in the upper troposphere and in boundary layer air affected by nitrogen oxide emissions from recently wetted soils. This latter effect, along with enhanced deposition to the forested areas, contributes to a latitudinal gradient of ozone in the lower troposphere. Biogenic volatile organic compounds are also important in defining the composition both for the boundary layer and upper tropospheric convective outflow. Mineral dust was found to be the most abundant and ubiquitous aerosol type in the atmosphere over Western Africa. Data

  13. Weathering and monsoonal evolution in the Eastern Himalayas since 13 Ma from detrital geochemistry, Kameng River Section, Arunachal Pradesh

    NASA Astrophysics Data System (ADS)

    Vögeli, Natalie; Van der Beek, Peter; Najman, Yani; Huyghe, Pascale

    2015-04-01

    The link between tectonics, erosion and climate has become an important subject to ongoing research in the last years (Clift et al. (2008), amongst others). The young Himalayan orogeny is the perfect laboratory for its study. The Neogene sedimentary foreland basin of the Himalaya contains a record of tectonics and paleoclimate since Miocene times, within the so called Siwalik Group. Therefore several sedimentary sections within the Himalayan foreland basin along strike in the Himalayan range have been dated and studied regarding exhumation rates, provenance and paleoclimatology (e.g. Quade and Cerling, 1995; Ghosh et al., 2004; Sanyal et al., 2004; van der Beek et al., 2006). Lateral variations have been observed and changes in exhumation rate as well as climate change in the past especially the strengthening of the Asian summer monsoon is still debated. Several paleoclimatological studies in the western Himalaya were conducted (Quade and Cerling, 1995; Najman et al., 2003; Huyghe et al., 2005), but the eastern part of the mountain range remains poorly studied. The Himalaya has a major influence on global and regional climate. The major force driving the evolution of this mountain belt is the India-Asia convergence, nevertheless it has been suggested that the monsoonal climate plays a major role for the erosion and relief pattern (Bookhagen and Burbank, 2006; Clift et al., 2008; Iaffaldano et al., 2011). Exhumation rates in the central Himalayas are more or less constant over last 13 Ma in the order of 1.8 km/myr, whereas exhumation rates in the eastern syntaxis increased post 3 Ma (Chirouze et al., 2013) to reach up to 10km/myr in the recent past. In this study we use a multidisciplinary approach in order to better understand the interplay of monsoon and weathering regime during the Mid Miocene to Pleistocene in the Himalaya. Therefore a sedimentary section in the eastern Himalaya was sampled. Pairs of fine and coarse grained sediment samples were taken in the

  14. Stable isotopes in monsoon precipitation and water vapour in Nagqu, Tibet, and their implications for monsoon moisture

    NASA Astrophysics Data System (ADS)

    He, Siyuan; Richards, Keith

    2016-09-01

    Understanding climate variations over the Qinghai-Tibetan plateau has become essential because the high plateau sustains various ecosystems and water sources, and impacts on the Asian monsoon system. This paper provides new information from isotopic signals in meteoric water and atmospheric water vapour on the Qinghai-Tibetan Plateau using high frequency observation data over a relatively short period. The aim is to explore temporal moisture changes and annual variations at the onset and during the summer monsoon season at a transitional site with respect to the monsoon influence. Data show that high frequency and short period observations can reveal typical moisture changes from the pre-monsoon to the monsoon seasons (2010), and the large variation in isotopic signals in different years with respect to active/inactive periods during a mature phase of the monsoon (2011), especially inferring from the temporal changes in the d-excess of precipitation and its relationship with δ18O values, when higher d-excess is found in the pre-monsoon precipitation. In this transition zone on a daily basis, δ18O values in precipitation are controlled mainly by the amount of rainfall during the monsoon season, while temperature seems more important before the onset of monsoon. Furthermore, the ;amount effect; is significant for night-time rain events. From comparison of signals in both the precipitation and water vapour, an inconsistent relationship between d-excess values suggests various moisture fluxes are active in a short period. The temporal pattern of isotopic signal change from the onset of the monsoon to the mature monsoon phase provides information about the larger circulation dynamics of the Asian monsoon.

  15. Coupled multi-disciplinary composites behavior simulation

    NASA Technical Reports Server (NTRS)

    Singhal, Surendra N.; Murthy, Pappu L. N.; Chamis, Christos C.

    1993-01-01

    The capabilities of the computer code CSTEM (Coupled Structural/Thermal/Electro-Magnetic Analysis) are discussed and demonstrated. CSTEM computationally simulates the coupled response of layered multi-material composite structures subjected to simultaneous thermal, structural, vibration, acoustic, and electromagnetic loads and includes the effect of aggressive environments. The composite material behavior and structural response is determined at its various inherent scales: constituents (fiber/matrix), ply, laminate, and structural component. The thermal and mechanical properties of the constituents are considered to be nonlinearly dependent on various parameters such as temperature and moisture. The acoustic and electromagnetic properties also include dependence on vibration and electromagnetic wave frequencies, respectively. The simulation is based on a three dimensional finite element analysis in conjunction with composite mechanics and with structural tailoring codes, and with acoustic and electromagnetic analysis methods. An aircraft engine composite fan blade is selected as a typical structural component to demonstrate the CSTEM capabilities. Results of various coupled multi-disciplinary heat transfer, structural, vibration, acoustic, and electromagnetic analyses for temperature distribution, stress and displacement response, deformed shape, vibration frequencies, mode shapes, acoustic noise, and electromagnetic reflection from the fan blade are discussed for their coupled effects in hot and humid environments. Collectively, these results demonstrate the effectiveness of the CSTEM code in capturing the coupled effects on the various responses of composite structures subjected to simultaneous multiple real-life loads.

  16. AIAA/USAF/NASA/OAI Symposium on Multidisciplinary Analysis and Optimization, 4th, Cleveland, OH, Sept. 21-23, 1992, Technical Papers. Pts. 1 & 2

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The papers presented at the symposium cover aerodynamics, design applications, propulsion systems, high-speed flight, structures, controls, sensitivity analysis, optimization algorithms, and space structures applications. Other topics include helicopter rotor design, artificial intelligence/neural nets, and computational aspects of optimization. Papers are included on flutter calculations for a system with interacting nonlinearities, optimization in solid rocket booster application, improving the efficiency of aerodynamic shape optimization procedures, nonlinear control theory, and probabilistic structural analysis of space truss structures for nonuniform thermal environmental effects.

  17. Prediction of dominant intraseasonal modes in the East Asian-western North Pacific summer monsoon

    NASA Astrophysics Data System (ADS)

    Oh, Hyoeun; Ha, Kyung-Ja

    2016-10-01

    Intraseasonal monsoon prediction is the most imperative task, but there remains an enduring challenge in climate science. The present study aims to provide a physical understanding of the sources for prediction of dominant intraseasonal modes in the East Asian-western North Pacific summer monsoon (EA-WNPSM): pre-Meiyu&Baiu, Changma&Meiyu, WNPSM, and monsoon gyre modes classified by the self-organizing map analysis. Here, we use stepwise regression to determine the predictors for the four modes in the EA-WNPSM. The selected predictors are based on the persistent and tendency signals of the sea surface temperature (SST)/2m air temperature and sea level pressure fields, which reflect the asymmetric response to the El Niño Southern Oscillation (ENSO) and the ocean and land surface anomalous conditions. For the pre-Meiyu&Baiu mode, the SST cooling tendency over the western North Pacific (WNP), which persists into summer, is the distinguishing contributor that results in strong baroclinic instability. A major precursor for the Changma&Meiyu mode is related to the WNP subtropical high, induced by the persistent SST difference between the Indian Ocean and the western Pacific. The WNPSM mode is mostly affected by the Pacific-Japan pattern, and monsoon gyre mode is primarily associated with a persistent SST cooling over the tropical Indian Ocean by the preceding ENSO signal. This study carries important implications for prediction by establishing valuable precursors of the four modes including nonlinear characteristics.

  18. Variability in AIRS CO2 during active and break phases of Indian summer monsoon.

    PubMed

    Revadekar, J V; Ravi Kumar, K; Tiwari, Yogesh K; Valsala, Vinu

    2016-01-15

    Due to human activities, the atmospheric concentration of Carbon Dioxide (CO2) has been rising extensively since the Industrial Revolution. Indian summer monsoon (ISM) has a dominant westerly component from ocean to land with a strong tendency to ascend and hence may have role in CO2 distribution in lower and middle troposphere over Indian sub-continent. A substantial component of ISM variability arises from the fluctuations on the intra-seasonal scale between active and break phases which correspond to strong and weak monsoon circulation. In view of the above, an attempt is made in this study to examine the AIRS/AQUA satellite retrieved CO2 distribution in response to atmospheric circulation with focus on active and break phase. Correlation analysis indicates the increase in AIRS CO2 linked with strong monsoon circulation. Study also reveals that anomalous circulation pattern during active and break phase show resemblance with high and low values of AIRS CO2. Homogeneous monsoon regions of India show substantial increase in CO2 levels during active phase. Hilly regions of India show strong contrast in CO2 and vertical velocity during active and break phases.

  19. The relationship between Arabian Sea upwelling and Indian Monsoon revisited in a high resolution ocean simulation

    NASA Astrophysics Data System (ADS)

    Yi, Xing; Hünicke, Birgit; Tim, Nele; Zorita, Eduardo

    2017-03-01

    Studies based on sediment records, sea-surface temperature and wind suggest that upwelling along the western coast of Arabian Sea is strongly affected by the Indian summer Monsoon. We examine this relationship directly in an eddy-resolving global ocean simulation STORM driven by atmospheric reanalysis over the last 61 years. With its very high spatial resolution (10 km), STORM allows us to identify characteristics of the upwelling system. We analyse the co-variability between upwelling and meteorological and oceanic variables from 1950 to 2010. The analysis reveals high interannual correlations between coastal upwelling and along-shore wind-stress (r = 0.73) as well as with sea-surface temperature (r = -0.83). However, the correlation between the upwelling and the Monsoon is small. We find an atmospheric circulation pattern different from the one that drives the Monsoon as the main modulator of the upwelling variability. In spite of this, the patterns of temperature anomalies that are either linked to Arabian Sea upwelling or to the Monsoon are spatially quite similar, although the physical mechanisms of these links are different. In addition, no long-term trend is detected in our modelled upwelling in the Arabian Sea.

  20. Monsoon triggered formation of Quaternary alluvial megafans in the interior of Oman

    NASA Astrophysics Data System (ADS)

    Blechschmidt, Ingo; Matter, Albert; Preusser, Frank; Rieke-Zapp, Dirk

    2009-09-01

    A vast bajada consisting of coalescing low-gradient (< 0.3°) alluvial fans exceeding 100 km in length formed along the southwestern margin of the Oman Mountains. It comprises an old fan sequence of inferred Miocene to Pliocene age termed Barzaman Formation, diagenetically highly altered to dolomitic clays, and a thin veneer of weakly cemented Quaternary gravels. A combination of remote sensing, lithological analyses and luminescence dating is used to interpret the complex aggradation history of the Quaternary alluvial fans from the interior of Oman in the context of independent regional climate records. From satellite imagery and clast analysis four fans can be discerned in the study area. While two early periods of fan formation are tentatively correlated to the Miocene-Pliocene and the Early Pleistocene, luminescence dating allows the distinction of five phases of fan aggradation during the Middle-Late Pleistocene. These phases are correlated with pluvial periods from Marine Isotope Stage (MIS) 11 through 3, when southern Arabia was affected by monsoonal precipitation. It is concluded that the aggradation of the alluvial fans was triggered by the interplay of increased sediment production during arid periods and high rainfall with enhanced erosion of hillslopes and transport rates during strong monsoon phases. However, the lack of fine-grained sediments, bioturbation and organic material implies that although the Quaternary fans are sourced by monsoonal rains they formed in a semi-arid environment. Thus, it appears that, in contrast to the Oman Mountains, the interior was not directly affected by monsoonal precipitation.

  1. A correlated shortening of the North and South American monsoon seasons in the past few decades

    NASA Astrophysics Data System (ADS)

    Arias, Paola A.; Fu, Rong; Vera, Carolina; Rojas, Maisa

    2015-12-01

    Our observational analysis shows that the wet seasons of the American monsoon systems have shortened since 1978 due to correlated earlier retreats of the North American monsoon (NAM) and late onsets of the southern Amazon wet season, an important part of the South American monsoon (SAM). These changes are related to the combination of the global sea surface temperature (SST) warming mode, the El Niño-Southern Oscillation (ENSO), the Atlantic Multidecadal Oscillation (AMO), the westward shift of the North Atlantic subtropical high (NASH), and the enhancement of Pacific South American and Pacific North American wave train patterns, which induces variations of the regional circulation at interannual and decadal scales. The joint contributions from these forcing factors are associated with a stronger and more equatorward regional Hadley cell, which enhances convergence towards the equator, strengthening and possibly delaying the retreat of the tropical part of the NAM. This in turn accelerates the demise of the northern NAM and delays the reversal of the cross-equatorial flow over South America, reducing moisture transport to the SAM and delaying its onset. In addition, the thermodynamic response to warming appears to cause local drier land conditions over both regions, reinforcing the observed changes in these monsoons. Although previous studies have identified the isolated influence of the regional Hadley cell, ENSO, AMO, global SST warming, and NASH on the NAM, the correlated changes between NAM and SAM through variations of the cross-equatorial flow had not been established before.

  2. Combined influence of remote and local SST forcing on Indian Summer Monsoon Rainfall variability

    NASA Astrophysics Data System (ADS)

    Chakravorty, Soumi; Gnanaseelan, C.; Pillai, P. A.

    2016-11-01

    The combined influence of tropical Indian Ocean (TIO) and Pacific Ocean (TPO) sea surface temperature (SST) anomalies on Indian summer monsoon rainfall (ISMR) variability is studied in the context of mid-1970s regime shift. The rainfall pattern on the various stages of monsoon during the developing and decaying summer of El Niño is emphasized. Analysis reveals that ISMR anomalies during El Niño developing summer in epoch-1 (1950-1979) are mainly driven by El Niño forcing throughout the season, whereas TIO SST exhibits only a passive influence. On the other hand in epoch-2 (1980-2009) ISMR does not show any significant relation with Pacific during the onset phase of monsoon whereas withdrawal phase is strongly influenced by El Niño. Again the eastern Indian Ocean cooling and westward shift in northwest Pacific (NWP) cyclonic circulation during epoch-2 have strong positive influence on the rainfall over the central and eastern India during the matured phase of monsoon. ISMR in the El Niño decaying summer does not show any significant anomalies in epoch-1 as both Pacific and Indian Ocean warming dissipate by the summer. On the other hand in epoch-2 ISMR anomalies are significant and display strong variability throughout the season. In the onset phase of monsoon, central and east India experience strong negative precipitation anomalies due to westward extension of persistent NWP anticyclone (forced by persisting Indian Ocean warming). The persistent TIO warming induces positive precipitation anomalies in the withdrawal phase of monsoon by changing the atmospheric circulation and modulating the water vapour flux. Moisture budget analysis unravels the dominant processes responsible for the differences between the two epochs. The moisture convergence and moisture advection are very weak (strong) over Indian land mass during epoch-1 (epoch-2) in El Niño decaying summer. The changing moisture availability and convergence play important role in explaining the weakening

  3. The link between Tibetan Plateau monsoon and Indian summer precipitation: a linear diagnostic perspective

    NASA Astrophysics Data System (ADS)

    Ge, Fei; Sielmann, Frank; Zhu, Xiuhua; Fraedrich, Klaus; Zhi, Xiefei; Peng, Ting; Wang, Lei

    2017-03-01

    The thermal forcing of the Tibetan Plateau (TP) is analyzed to investigate the formation and variability of Tibetan Plateau Summer Monsoon (TPSM), which affects the climates of the surrounding regions, in particular the Indian summer monsoon precipitation. Dynamic composites and statistical analyses indicate that the Indian summer monsoon precipitation is less/greater than normal during the strong/weak TPSM. Strong (weak) TPSM is associated with an anomalous near surface cyclone (anticyclone) over the western part of the Tibetan Plateau, enhancing (reducing) the westerly flow along its southern flank, suppressing (favoring) the meridional flow of warm and moist air from the Indian ocean and thus cutting (providing) moisture supply for the northern part of India and its monsoonal rainfall. These results are complemented by a dynamic and thermodynamic analysis: (i) A linear thermal vorticity forcing primarily describes the influence of the asymmetric heating of TP generating an anomalous stationary wave flux. Composite analysis of anomalous stationary wave flux activity (after Plumb in J Atmos Sci 42:217-229, 1985) strongly indicate that non-orographic effects (diabatic heating and/or interaction with transient eddies) of the Tibetan Plateau contribute to the generation of an anomalous cyclone (anti-cyclone) over the western TP. (ii) Anomalous TPSM generation shows that strong TPSM years are related to the positive surface sensible heating anomalies over the eastern TP favoring the strong diabatic heating in summer. While negative TPSM years are associated with the atmospheric circulation anomalies during the preceding spring, enhancing northerly dry-cold air intrusions into TP, which may weaken the condensational heat release in the middle and upper troposphere, leading to a weaker than normal summer monsoon over the TP in summer.

  4. Multidisciplinary Management of Laryngeal Carcinoma

    SciTech Connect

    Mendenhall, William M. Mancuso, Anthony A.; Hinerman, Russell W.; Malyapa, Robert S.; Werning, John W.; Amdur, Robert J.; Villaret, Douglas B.

    2007-10-01

    The management of head and neck cancer has evolved into a multidisciplinary approach in which patients are evaluated before treatment and decisions depend on prospective multi-institutional trials, as well as retrospective outcome studies. The choice of one or more modalities to use in a given case varies with the tumor site and extent, as exemplified in the treatment of laryngeal squamous cell carcinomas. The goals of treatment include cure, laryngeal voice preservation, voice quality, optimal swallowing, and minimal xerostomia. Treatment options include transoral laser excision, radiotherapy (both definitive and postoperative), open partial laryngectomy, total laryngectomy, and neck dissection. The likelihood of local control and preservation of laryngeal function is related to tumor volume. Patients who have a relatively high risk of local recurrence undergo follow-up computed tomography scans every 3-4 months for the first 2 years after radiotherapy. Patients with suspicious findings on computed tomography might benefit from fluorodeoxyglucose positron emission tomography to differentiate post-radiotherapy changes from tumor.

  5. Multidisciplinary approaches to solar hydrogen

    PubMed Central

    Bren, Kara L.

    2015-01-01

    This review summarizes three different approaches to engineering systems for the solar-driven evolution of hydrogen fuel from water: molecular, nanomaterials and biomolecular. Molecular systems have the advantage of being highly amenable to modification and detailed study and have provided great insight into photophysics, electron transfer and catalytic mechanism. However, they tend to display poor stability. Systems based on nanomaterials are more robust but also are more difficult to synthesize in a controlled manner and to modify and study in detail. Biomolecular systems share many properties with molecular systems and have the advantage of displaying inherently high efficiencies for light absorption, electron–hole separation and catalysis. However, biological systems must be engineered to couple modules that capture and convert solar photons to modules that produce hydrogen fuel. Furthermore, biological systems are prone to degradation when employed in vitro. Advances that use combinations of these three tactics also are described. Multidisciplinary approaches to this problem allow scientists to take advantage of the best features of biological, molecular and nanomaterials systems provided that the components can be coupled for efficient function. PMID:26052425

  6. Pineal lesions: a multidisciplinary challenge.

    PubMed

    Westphal, Manfred; Emami, Pedram

    2015-01-01

    The pineal region is a complex anatomical compartment, harbouring the pineal gland surrounded by the quadrigeminal plate and the confluents of the internal cerebral veins to form the vein of Galen. The complexity of lesions in that region, however, goes far beyond the pineal parenchyma proper. Originating in the pineal gland, there are not only benign cysts but also numerous different tumour types. In addition, lesions such as tectal gliomas, tentorial meningiomas and choroid plexus papillomas arise from the surrounding structures, occupying that regions. Furthermore, the area has an affinity for metastatic lesions. Vascular lesions complete the spectrum mainly as small tectal arteriovenous malformations or cavernous haemangiomas.Taken together, there is a wide spectrum of lesions, many unique to that region, which call for a multidisciplinary approach. The limited access and anatomical complexity have generated a spectrum of anatomical approaches and raised the interest for neuroendoscopic approaches. Equally complex is the spectrum of treatment modalities such as microsurgery as the main option but stereotactic radiosurgery as an alternative or adjuvant to surgery for selected cases, radiation as for germinoma (see below) and or combinatorial chemotherapy, which may need to precede any other ablative technique as constituents.In this context, we review the current literature and our own series to obtain a snapshot sentiment of how to approach pineal lesions, how to interrelate alternative/competing concepts and review the recent technological advances.

  7. Temporomandibular joint multidisciplinary team clinic.

    PubMed

    Ahmed, Nabeela; Poate, Tim; Nacher-Garcia, Cristina; Pugh, Nicola; Cowgill, Helen; Page, Lisa; Matthews, N Shaun

    2014-11-01

    Patients with dysfunction of the temporomandibular joint (TMJ) commonly present to oral and maxillofacial departments and are increasingly being managed by a subspecialist group of surgeons. We review the outcomes of patients attending a specialist TMJ multidisciplinary team (MDT) clinic. All patients are simultaneously reviewed by a consultant oral and maxillofacial surgeon, consultant in oral medicine, specialist physiotherapist, and maxillofacial prosthetist, and they can also see a consultant liaison psychiatrist. They are referred from primary, secondary, and tertiary care when medical and surgical treatment in the routine TMJ clinic has failed, and are triaged by the attending maxillofacial surgeon. On discharge they are returned to the care of the referring practitioner. We review the outcomes of patients attending this clinic over a 2-year period and show improvements in pain scores and maximal incisal opening, as well as quality of life outcome measures. All units in the UK with an interest in the management of diseases of the TMJ should consider establishing this type of clinic and should use available resources and expertise to maximise outcomes.

  8. CMIP5 model-simulated onset, duration and intensity of the Asian summer monsoon in current and future climate

    NASA Astrophysics Data System (ADS)

    Dong, Guangtao; Zhang, H.; Moise, A.; Hanson, L.; Liang, P.; Ye, H.

    2016-01-01

    A number of significant weaknesses existed in our previous analysis of the changes in the Asian monsoon onset/retreat from coupled model intercomparison project phase 3 (CMIP3) models, including a lack of statistical significance tests, a small number of models analysed, and limited understanding of the causes of model uncertainties. Yet, the latest IPCC report acknowledges limited confidence for projected changes in monsoon onset/retreat. In this study we revisit the topic by expanding the analysis to a large number of CMIP5 models over much longer period and with more diagnoses. Daily 850 hPa wind, volumetric atmospheric precipitable water and rainfall data from 26 CMIP5 models over two sets of 50-year periods are used in this study. The overall model skill in reproducing the temporal and spatial patterns of the monsoon development is similar between CMIP3 and CMIP5 models. They are able to show distinct regional characteristics in the evolutions of Indian summer monsoon (ISM), East Asian summer monsoon (EASM) and West North Pacific summer monsoon (WNPSM). Nevertheless, the averaged onset dates vary significantly among the models. Large uncertainty exists in model-simulated changes in onset/retreat dates and the extent of uncertainty is comparable to that in CMIP3 models. Under global warming, a majority of the models tend to suggest delayed onset for the south Asian monsoon in the eastern part of tropical Indian Ocean and Indochina Peninsula and nearby region, primarily due to weakened tropical circulations and eastward shift of the Walker circulation. The earlier onset over the Arabian Sea and part of the Indian subcontinent in a number of the models are related to an enhanced southwesterly flow in the region. Weak changes in other domains are due to the offsetting results among the models, with some models showing earlier onsets but others showing delayed onsets. Different from the analysis of CMIP3 model results, this analysis highlights the importance of SST

  9. Asian Eocene monsoons as revealed by leaf architectural signatures

    NASA Astrophysics Data System (ADS)

    Spicer, Robert A.; Yang, Jian; Herman, Alexei B.; Kodrul, Tatiana; Maslova, Natalia; Spicer, Teresa E. V.; Aleksandrova, Galina; Jin, Jianhua

    2016-09-01

    The onset and development of the Asian monsoon systems is a topic that has attracted considerable research effort but proxy data limitations, coupled with a diversity of definitions and metrics characterizing monsoon phenomena, have generated much debate. Failure of geological proxies to yield metrics capable of distinguishing between rainfall seasonality induced by migrations of the Inter-tropical Convergence Zone (ITCZ) from that attributable to topographically modified seasonal pressure reversals has frustrated attempts to understand mechanisms underpinning monsoon development and dynamics. Here we circumvent the use of such single climate parameter metrics in favor of detecting directly the distinctive attributes of different monsoon regimes encoded in leaf fossils. Leaf form adapts to the prevailing climate, particularly under the extreme seasonal stresses imposed by monsoons, so it is likely that fossil leaves carry a unique signature of past monsoon regimes. Leaf form trait spectra obtained from fossils from Eocene basins in southern China were compared with those seen in modern leaves growing under known climate regimes. The fossil leaf trait spectra, including those derived from previously published fossil floras from northwestern India, were most similar to those found in vegetation exposed to the modern Indonesia-Australia Monsoon (I-AM), which is largely a product of seasonal migrations of the ITCZ. The presence of this distinctive leaf physiognomic signature suggests that although a monsoon climate existed in Eocene time across southern Asia the characteristics of the modern topographically-enhanced South Asia Monsoon had yet to develop. By the Eocene leaves in South Asia had become well adapted to an I-AM type regime across many taxa and points to the existence of a pervasive monsoon climate prior to the Eocene. No fossil trait spectra typical of exposure to the modern East Asia monsoon were seen, suggesting the effects of this system in southern

  10. Effects of mountain uplift on global monsoon precipitation

    NASA Astrophysics Data System (ADS)

    Lee, June-Yi; Wang, Bin; Seo, Kyong-Hwan; Ha, Kyung-Ja; Kitoh, Akio; Liu, Jian

    2015-08-01

    This study explores the role of the global mountain uplift (MU), which occurred during the middle and late Cenozoic, in modulating global monsoon precipitation using the Meteorological Research Institute atmosphere-ocean coupled model experiments. First, the MU causes changes in the annual mean of major monsoon precipitation. Although the annual mean precipitation over the entire globe remains about the same from the no-mountain experiment (MU0) to the realistic MU (MU1), that over the Asian-Australian monsoon region and Americas increases by about 16% and 9%, respectively. Second, the MU plays an essential role in advancing seasonal march, and summer-monsoon onset, especially in the Northern Hemisphere, by shaping pre-monsoon circulation. The rainy seasons are lengthened as a result of the earlier onset of the summer monsoon since the monsoon retreat is not sensitive to the MU. The East Asian monsoon is a unique consequence of the MU, while other monsoons are attributed primarily to land-sea distribution. Third, the strength of the global monsoon is shown to be substantially affected by the MU. In particular, the second annual cycle (AC) mode of global precipitation (the spring-autumn asymmetry mode) is more sensitive to the progressive MU than the first mode of the AC (the solstice mode), suggesting that the MU may have a greater impact during transition seasons than solstice seasons. Finally, the MU strongly modulates interannual variation in global monsoon precipitation in relation to El Niño and Southern Oscillation (ENSO). The Progressive MU changes not only the spatial distribution but also the periodicity of the first and second AC mode of global precipitation on interannual timescale.

  11. [Global brain metastases management strategy: a multidisciplinary-based approach].

    PubMed

    Métellus, P; Tallet, A; Dhermain, F; Reyns, N; Carpentier, A; Spano, J-P; Azria, D; Noël, G; Barlési, F; Taillibert, S; Le Rhun, É

    2015-02-01

    Brain metastases management has evolved over the last fifteen years and may use varying strategies, including more or less aggressive treatments, sometimes combined, leading to an improvement in patient's survival and quality of life. The therapeutic decision is subject to a multidisciplinary analysis, taking into account established prognostic factors including patient's general condition, extracerebral disease status and clinical and radiological presentation of lesions. In this article, we propose a management strategy based on the state of current knowledge and available therapeutic resources.

  12. Logit-normal mixed model for Indian monsoon precipitation

    NASA Astrophysics Data System (ADS)

    Dietz, L. R.; Chatterjee, S.

    2014-09-01

    Describing the nature and variability of Indian monsoon precipitation is a topic of much debate in the current literature. We suggest the use of a generalized linear mixed model (GLMM), specifically, the logit-normal mixed model, to describe the underlying structure of this complex climatic event. Four GLMM algorithms are described and simulations are performed to vet these algorithms before applying them to the Indian precipitation data. The logit-normal model was applied to light, moderate, and extreme rainfall. Findings indicated that physical constructs were preserved by the models, and random effects were significant in many cases. We also found GLMM estimation methods were sensitive to tuning parameters and assumptions and therefore, recommend use of multiple methods in applications. This work provides a novel use of GLMM and promotes its addition to the gamut of tools for analysis in studying climate phenomena.

  13. Urbanization causes nonstationarity in Indian Summer Monsoon Rainfall extremes

    NASA Astrophysics Data System (ADS)

    Singh, Jitendra; Vittal, H.; Karmakar, Subhankar; Ghosh, Subimal; Niyogi, Dev

    2016-11-01

    Global and local environmental changes are likely to introduce nonstationarity in the characteristics of Indian Summer Monsoon Rainfall (ISMR) extremes. Here we perform a nonstationary frequency analysis on ISMR extremes in a Generalized Additive Model for Location, Scale and Shape framework with a cluster of 74 models, considering nonstationarity in different possible combinations. Interestingly, we observe significant nonstationarity in ISMR extremes in urbanizing/developing-urban areas (transitioning from rural to urban), compared to completely urbanized or rural areas. This presents a postulation that the extent of urbanization plays a significant role in introducing nonstationarity in ISMR extremes. We emphasize the effect of urbanization in changing the character of ISMR extremes, which further needs a scientific re-evaluation by implementing physics-based modeling. The impact of these observational studies will be critical in correcting the bias of model projections of ISMR.

  14. Late Holocene climate reorganisation and the North American Monsoon

    NASA Astrophysics Data System (ADS)

    Jones, Matthew D.; Metcalfe, Sarah E.; Davies, Sarah J.; Noren, Anders

    2015-09-01

    The North American Monsoon (NAM) provides the majority of rainfall for central and northern Mexico as well as parts of the south west USA. The controls over the strength of the NAM in a given year are complex, and include both Pacific and Atlantic systems. We present here an annually resolved proxy reconstruction of NAM rainfall variability over the last ˜6 ka, from an inwash record from the Laguna de Juanacatlán, Mexico. This high resolution, exceptionally well dated record allows changes in the NAM through the latter half of the Holocene to be investigated in both time and space domains, improving our understanding of the controls on the system. Our analysis shows a shift in conditions between c. 4 and 3 ka BP, after which clear ENSO/PDO type forcing patterns are evident.

  15. An initiative in multidisciplinary optimization of rotorcraft

    NASA Technical Reports Server (NTRS)

    Adelman, Howard M.; Mantay, Wayne R.

    1989-01-01

    Described is a joint NASA/Army initiative at the Langley Research Center to develop optimization procedures aimed at improving the rotor blade design process by integrating appropriate disciplines and accounting for important interactions among the disciplines. The activity is being guided by a Steering Committee made up of key NASA and Army researchers and managers. The committee, which has been named IRASC (Integrated Rotorcraft Analysis Steering Committee), has defined two principal foci for the activity: a white paper which sets forth the goals and plans of the effort; and a rotor design project which will validate the basic constituents, as well as the overall design methodology for multidisciplinary optimization. The optimization formulation is described in terms of the objective function, design variables, and constraints. Additionally, some of the analysis aspects are discussed and an initial attempt at defining the interdisciplinary couplings is summarized. At this writing, some significant progress has been made, principally in the areas of single discipline optimization. Results are given which represent accomplishments in rotor aerodynamic performance optimization for minimum hover horsepower, rotor dynamic optimization for vibration reduction, and rotor structural optimization for minimum weight.

  16. An initiative in multidisciplinary optimization of rotorcraft

    NASA Technical Reports Server (NTRS)

    Adelman, Howard M.; Mantay, Wayne R.

    1988-01-01

    Described is a joint NASA/Army initiative at the Langley Research Center to develop optimization procedures aimed at improving the rotor blade design process by integrating appropriate disciplines and accounting for important interactions among the disciplines. The activity is being guided by a Steering Committee made up of key NASA and Army researchers and managers. The committee, which has been named IRASC (Integrated Rotorcraft Analysis Steering Committee), has defined two principal foci for the activity: a white paper which sets forth the goals and plans of the effort; and a rotor design project which will validate the basic constituents, as well as the overall design methodology for multidisciplinary optimization. The paper describes the optimization formulation in terms of the objective function, design variables, and constraints. Additionally, some of the analysis aspects are discussed and an initial attempt at defining the interdisciplinary couplings is summarized. At this writing, some significant progress has been made, principally in the areas of single discipline optimization. Results are given which represent accomplishments in rotor aerodynamic performance optimization for minimum hover horsepower, rotor dynamic optimization for vibration reduction, and rotor structural optimization for minimum weight.

  17. The role of East Asian monsoon system in shaping population divergence and dynamics of a constructive desert shrub Reaumuria soongarica

    PubMed Central

    Yin, Hengxia; Yan, Xia; Shi, Yong; Qian, Chaoju; Li, Zhonghu; Zhang, Wen; Wang, Lirong; Li, Yi; Li, Xiaoze; Chen, Guoxiong; Li, Xinrong; Nevo, Eviatar; Ma, Xiao-Fei

    2015-01-01

    Both of the uplift of Qinghai-Tibet Plateau (QTP) and the development of East Asian monsoon system (EAMS) could have comprehensively impacted the formation and evolution of Arid Central Asia (ACA). To understand how desert plants endemic to ACA responded to these two factors, we profiled the historical population dynamics and distribution range shift of a constructive desert shrub Reaumuria soongarica (Tamaricaceae) based on species wide investigation of sequence variation of chloroplast DNA and nuclear ribosomal ITS. Phylogenetic analysis uncovered a deep divergence occurring at ca. 2.96 Mya between the western and eastern lineages of R. soongarica, and ecological niche modeling analysis strongly supported that the monsoonal climate could have fragmented its habitats in both glacial and interglacial periods and impelled its intraspecific divergence. Additionally, the population from the east monsoonal zone expanded rapidly, suggesting that the local monsoonal climate significantly impacted its population dynamics. The isolation by distance tests supported strong maternal gene flow along the direction of the East Asian winter monsoon, whose intensification induced the genetic admixture along the latitudinal populations of R. soongarica. Our results presented a new case that the development of EAMS had prominently impacted the intraspecific divergence and population dynamics of this desert plant. PMID:26510579

  18. The role of East Asian monsoon system in shaping population divergence and dynamics of a constructive desert shrub Reaumuria soongarica.

    PubMed

    Yin, Hengxia; Yan, Xia; Shi, Yong; Qian, Chaoju; Li, Zhonghu; Zhang, Wen; Wang, Lirong; Li, Yi; Li, Xiaoze; Chen, Guoxiong; Li, Xinrong; Nevo, Eviatar; Ma, Xiao-Fei

    2015-10-29

    Both of the uplift of Qinghai-Tibet Plateau (QTP) and the development of East Asian monsoon system (EAMS) could have comprehensively impacted the formation and evolution of Arid Central Asia (ACA). To understand how desert plants endemic to ACA responded to these two factors, we profiled the historical population dynamics and distribution range shift of a constructive desert shrub Reaumuria soongarica (Tamaricaceae) based on species wide investigation of sequence variation of chloroplast DNA and nuclear ribosomal ITS. Phylogenetic analysis uncovered a deep divergence occurring at ca. 2.96 Mya between the western and eastern lineages of R. soongarica, and ecological niche modeling analysis strongly supported that the monsoonal climate could have fragmented its habitats in both glacial and interglacial periods and impelled its intraspecific divergence. Additionally, the population from the east monsoonal zone expanded rapidly, suggesting that the local monsoonal climate significantly impacted its population dynamics. The isolation by distance tests supported strong maternal gene flow along the direction of the East Asian winter monsoon, whose intensification induced the genetic admixture along the latitudinal populations of R. soongarica. Our results presented a new case that the development of EAMS had prominently impacted the intraspecific divergence and population dynamics of this desert plant.

  19. Influence of Indian summer monsoon variability on the surface waves in the coastal regions of eastern Arabian Sea

    NASA Astrophysics Data System (ADS)

    Sanil Kumar, V.; George, Jesbin

    2016-10-01

    We assess the influence of monsoon variability on the surface waves using measured wave data covering 7 years and reanalysis data from 1979 to 2015 during the Indian summer monsoon (JJAS) in the eastern Arabian Sea. The inter-annual comparison shows that the percentage of higher wave heights ( > 2.5 m) is higher ( ˜ 26%) in 2014 than in other years due to the higher monsoon wind speed (average speed ˜ 7.3 m s-1) in 2014. Due to the delayed monsoon, monthly average significant wave height (Hm0) of June was lowest (˜ 1.5 m) in 2009. The spectral peak shifted to lower frequencies in September due to the reduction of wind seas as a result of decrease in monsoon intensity. The study shows high positive correlation (r ˜ 0.84) between average low-level jet (LLJ) for the block 0-15° N, 50-75° E and Hm0 of eastern Arabian Sea in all the months except in August (r ˜ 0.66). The time series data on wave height shows oscillations with periods 5 to 20 days. Wavelet coherence analysis indicates that the LLJ and Hm0 are in-phase related (phase angle 0°) almost all the time and LLJ leads Hm0. The monsoon seasonal anomaly of Hm0 is found to have a negative relationship with the Oceanic Niño Index indicating that the monsoon average Hm0 is relatively low during the strong El Niño years.

  20. Assessing organisational readiness for change: use of diagnostic analysis prior to the implementation of a multidisciplinary assessment for acute stroke care

    PubMed Central

    Hamilton, Sharon; McLaren, Susan; Mulhall, Anne

    2007-01-01

    Background Achieving evidence-based practice in health care is integral to the drive for quality improvement in the National Health Service in the UK. Encapsulated within this policy agenda are challenges inherent in leading and managing organisational change. Not least of these is the need to change the behaviours of individuals and groups in order to embed new practices. Such changes are set within a context of organisational culture that can present a number of barriers and facilitators to change. Diagnostic analysis has been recommended as a precursor to the implementation of change to enable such barriers and facilitators to be identified and a targeted implementation strategy developed. Although diagnostic analysis is recommended, there is a paucity of advice on appropriate methods to use. This paper addresses the paucity and builds on previous work by recommending a mixed method approach to diagnostic analysis comprising both quantitative and qualitative data. Methods Twenty staff members with strategic accountability for stroke care were purposively sampled to take part in semi-structured interviews. Six recently discharged patients were also interviewed. Focus groups were conducted with one group of registered ward-based nurses (n = 5) and three specialist registrars (n = 3) purposively selected for their interest in stroke care. All professional staff on the study wards were sent the Team Climate Inventory questionnaire (n = 206). This elicited a response rate of 72% (n = 148). Results A number of facilitators for change were identified, including stakeholder support, organisational commitment to education, strong team climate in some teams, exemplars of past successful organisational change, and positive working environments. A number of barriers were also identified, including: unidisciplinary assessment/recording practices, varying in structure and evidence-base; weak team climate in some teams; negative exemplars of organisational change; and

  1. Whey protein stories - An experiment in writing a multidisciplinary biography.

    PubMed

    Jensen, Tenna; Bechshoeft, Rasmus L; Giacalone, Davide; Otto, Marie Haulund; Castro-Mejía, Josue; Bin Ahmad, Hajar Fauzan; Reitelseder, Søren; Jespersen, Astrid Pernille

    2016-12-01

    This is an experimental, dual-purpose article about whey protein and how to conduct interdisciplinary analyses and writings. On the one hand, this article is a multidisciplinary commodity biography, which consists of five descriptions of whey protein written by the five different research groups involved in the interdisciplinary research project CALM(Counteracting Age-related loss of Skeletal Muscle Mass). On the other hand, it is a meta-analysis, which aims to uncover and highlight examples of how the five descriptions contribute to each other with insights into the contextualisation of knowledge, contrasts between the descriptions and the new dimensions they bring to established fields of interest. The meta-analysis also contains a discussion of interdisciplinary study objects and the usefulness of the multidisciplinary commodity biography as a format for interdisciplinary publications. The article contributes to the field of food studies with a multidisciplinary biography of whey protein - including its sensory qualities and challenges, insights into its cultural history, its nutritional value and effects on the human body and an analysis of how it is perceived by people who consume it. The biography thereby expands upon existing understandings of whey protein while discussing the usefulness of employing the commodity biography format in interdisciplinary writing. Moreover, the article contributes to the field of interdisciplinary research by providing a practical example of a joint publication and reflections upon the existence, interaction and possibilities of monodisciplinary knowledge structures within interdisciplinary studies and publications.

  2. Examining Intraseasonal Variability in the West African Monsoon Using the Superparameterized Community Climate System Model

    NASA Astrophysics Data System (ADS)

    McCrary, Rachel; Randall, David; Stan, Cristiana

    2013-04-01

    In West Africa, the ability to predict intraseasonal variations in rainfall would have important social and economic impacts for local populations. In particular, such predictions might be useful for estimating the timing of the monsoon onset and break periods in monsoon rains. Current theory suggests that on 25-90 day timescales, the West African monsoon (WAM) is influenced by intraseasonal variations in the Indo-Pacific region, namely the Madden Julian Oscillation (MJO) and the Asian summer monsoon. Unfortunately, most general circulation models (GCMs) show weak skill in simulating the seasonal variations in the WAM as well as intraseasonal variability in the Indo-Pacific. These model limitations make it difficult to study the dynamical links in variability across the tropics. Unlike traditional GCMs, models that have implemented the superparameterization (where traditional convective parameterizations are replaced by embedding a two dimensional cloud resolving model in each grid box) have been shown to be able to represent the WAM, the MJO and the Asian Summer Monsoon with reasonable fidelity. These model advances may allow us to study the teleconnections between the Indo-Pacific and West Africa in more detail. This study examines the intraseasonal variability of the WAM in the Superparameterized Community Climate System model (SP-CCSM). Results from the SP-CCSM are consistent with observations where intraseasonal variability accounts for 15-20% of the total variability in rainfall over West Africa during the monsoon season. We also show that on 25-90 day timescales, increases in precipitation over West Africa correspond with a northward shift of the African easterly jet and an increase in African easterly wave activity. Lag-composite analysis indicates that intraseasonal variations in WAM precipitation correspond with the North-South propagation of the MJO during boreal summer as well as the active and breaking phases of the Asian summer monsoon. Preliminary

  3. East Asian Monsoon controls on the inter-annual variability in precipitation isotope ratio in Japan

    NASA Astrophysics Data System (ADS)

    Kurita, N.; Fujiyoshi, Y.; Nakayama, T.; Matsumi, Y.; Kitagawa, H.

    2015-02-01

    To elucidate the mechanism for how the East Asian Monsoon (EAM) variability have influenced the isotope proxy records in Japan, we explore the primary driver of variations of precipitation isotopes at multiple temporal scales (event, seasonal and inter-annual scales). Using a new 1-year record of the isotopic composition of event-based precipitation and continuous near-surface water vapor at Nagoya in central Japan, we identify the key atmospheric processes controlling the storm-to-storm isotopic variations through an analysis of air mass sources and rainout history during the transport of moisture to the site, and then apply the identified processes to explain the inter-annual isotopic variability related to the EAM variability in the historical 17-year long Tokyo station record in the Global Network of Isotopes in Precipitation (GNIP). In the summer, southerly flows transport moisture with higher isotopic values from subtropical marine regions and bring warm rainfall enriched with heavy isotopes. The weak monsoon summer corresponds to enriched isotopic values in precipitation, reflecting higher contribution of warm rainfall to the total summer precipitation. In the strong monsoon summer, the sustaining Baiu rainband along the southern coast of Japan prevents moisture transport across Japan, so that the contribution of warm rainfall is reduced. In the winter, storm tracks are the dominant driver of storm-to-storm isotopic variation and relatively low isotopic values occur when a cold frontal rainband associated with extratropical cyclones passes off to the south of the Japan coast. The weak monsoon winter is characterized by lower isotopes in precipitation, due to the distribution of the cyclone tracks away from the southern coast of Japan. In contrast, the northward shift of the cyclone tracks and stronger development of cyclones during the strong monsoon winters decrease the contribution of cold frontal precipitation, resulting in higher isotopic values in

  4. Influence of dynamic and thermodynamic features on Indian summer monsoon

    SciTech Connect

    Babu, C.A.; Leena, P.; Priya, P.

    1996-12-31

    Indian summer monsoon plays vital role in the economy of the country. Being an agricultural country, the onset phase of monsoon is important since beginning of cultivation depends on rain-fed irrigation. Summer heating of the Asian land mass and subsequent differential heating between peninsular and north India are considered to be the principal cause for the summer monsoon. An east-west synoptic scale zonal circulation is observed over the Indian region during monsoon period which is similar to the planetary scale circulation. The ascending branch of this circulation is over northwest India and the descending branch is over the northeast India. This east-west zonal circulation is closely related to the monsoon activity. During the onset phase of monsoon spectacular changes occur in the dynamical and thermodynamic structure of the atmosphere. In this paper an attempt is made to diagnose the features of the atmosphere over the Indian region employing dynamical and thermodynamical parameters to as to bring out the relationship between structure of atmosphere and strength of monsoon. Preliminary results indicate that the strength of monsoon and its various epochs are influenced by dynamic and thermodynamic features of the atmosphere.

  5. Remote Sensing of Arizona Monsoons: Application of GOES Infrared Imagery

    NASA Astrophysics Data System (ADS)

    Carter, S.; Christensen, P. R.; Cerveny, R. S.

    2013-12-01

    Large, violent thunder and dust storms occur in the Phoenix area during monsoon season. Currently, the best ways to predict these dangerous and potentially damaging storms are not very accurate. The primary goal of this investigation is to attempt to develop a new technique to identify and predict these storms before they reach Phoenix. In order to address this question, two data sets (remote sensing satellite imagery and ground-based weather information) will be analyzed and compared against one another using time as a corresponding variable. The goal is to discern any correlations between data sets which be used as an indicator of imminent large monsoons. The moisture needed for the storms is carried to Arizona by events known as gulf surges (from the California Gulf); these will be the target of investigation. These chutes of moisture surge through Arizona, primarily up through Yuma in a northeasterly direction towards central/south central Arizona. The main goal is to identify if satellite imagery can be used as an accurate identifier of moisture movements preceding a storm in areas where ground measurements are not available. Presently, ground measurements of dew points are the primary technique by which these moisture surges are identified. However, while these measurements do have a fairly high temporal resolution (once an hour) they cover an awfully poor spacial range. Furthermore, it is suspected that because of interference to the instruments, the ground point data may not be as accurate as is preferred. On the other hand, satellite imagery such as GOES - the instrument used in this investigation - has both a remarkably high temporal resolution and spacial coverage. If a correlation can be demonstrated, then the high temporal resolution of the remote sensing data could be used as an identifier of oncoming monsoon storms. In order to proceed in this research, a software package known as Java Mission-planning and Analysis for Remote Sensing (JMARS) for

  6. Monsoon extremes and society over the past millennium on mainland Southeast Asia

    NASA Astrophysics Data System (ADS)

    Buckley, Brendan M.; Fletcher, Roland; Wang, Shi-Yu Simon; Zottoli, Brian; Pottier, Christophe

    2014-07-01

    The early 21st century has seen vigorous scientific interest in the Asian monsoon and significant development of paleo-proxies of monsoon strength. These include the Monsoon Asian Drought Atlas - a 700-year, gridded reconstruction of hydroclimate derived from 327 tree ring records - and several long speleothem records from China and India. Similar progress has been made on the study of monsoon climate dynamics through re-analysis data products and General Circulation Model diagnostics. The story has emerged of a variable monsoon over the latter Holocene, with extended droughts and anomalously wet episodes that occasionally and profoundly influenced the course of human history. We focus on Southeast Asia where an anomalous period of unstable climate coincided with the demise of the capital of the Khmer Empire at Angkor between the 14th and the 16th centuries, and we suggest that protracted periods of drought and deluge rain events, the latter of which damaged Angkor's extensive water management systems, may have been a significant factor in the subsequent transfer of the political capital away from Angkor. The late 16th and early 17th century experienced climate instability and the collapse of the Ming Dynasty in China under a period of drought, while Tonkin experienced floods and droughts throughout the 17th century. The 18th century was a period of great turmoil across Southeast Asia, when all of the region's polities saw great unrest and rapid realignment during one of the most extended periods of drought of the past millennium. New paleo-proxy records and the incorporation of historical documentation will improve future analyses of the interaction between climate extremes, social behavior and the collapse or disruption of regional societies, a subject of increasing concern given the uncertainties surrounding projections for future climate.

  7. Rapid weakening of Typhoon Chan-Hom (2015) in a monsoon gyre

    NASA Astrophysics Data System (ADS)

    Liang, Jia; Wu, Liguang; Gu, Guojun; Liu, Qingyuan

    2016-08-01

    A monsoon gyre is a low-frequency cyclonic circulation over the western North Pacific, which plays important roles in tropical cyclone formation and motion. This study shows that the interaction between a monsoon gyre and a tropical cyclone can lead to a sudden weakening of the tropical cyclone through an observational analysis of Typhoon Chan-Hom (2015). Typhoon Chan-Hom (2015) initially moved westward along ~10°N and sharply turned northeastward in the Philippine Sea at 0000 UTC 3 July. Its intensity decreased by 10.3 m s-1 within 12 h during the sudden northward turn. Such a rapid weakening event was failed to predict in all of the operational forecasts. It is found that Chan-Hom was coalescing with a large-scale monsoon gyre on the intraseasonal (15-30 day) timescale, while it experienced the sudden track change and rapid intensity weakening. The weak and loosely organized convection on the eastern side of the monsoon gyre at 1200 UTC 2 July rapidly enhanced into the well-organized convection within 6 h. The strong convection maintaining from 1800 UTC 2 July to 0600 UTC 3 July enhanced inflows outside the radius of 500 km from the tropical cyclone center, which prevented the inward transportation of mass and moisture into Chan-Hom, leading to the collapsing of the eastern part of the eyewall. As a result, Chan-Hom underwent the rapid weakening even under a large-scale environment favorable for intensification. The study suggests that the rapid weakening of a tropical cyclone can result from its interaction with a monsoon gyre.

  8. Multidisciplinary teamwork--myth or reality?

    PubMed

    Rowe, H

    1996-03-01

    The provision and delivery of health care has become increasingly complex in recent years due to technological innovation in medicine and increasing client expectations. The challenge for health care workers is to meet the purchasers' demands, one option may be to shift working practices from a functionalist approach to one of multidisciplinary teamwork. This paper explores one example of multidisciplinary teamwork and examines the processes which enhance and those that limit collaboration.

  9. Advanced Asian summer monsoon onset in recent decades

    NASA Astrophysics Data System (ADS)

    Kajikawa, Y.; Yasunari, T.; Yoshida, S.; Fujinami, H.

    2011-12-01

    Anthropogenic climate change in the Asian monsoon area is one of the most important issues due to the maximum population over the world. Many studies have revealed the long-term change of the Asian summer monsoon rainfall, especially over the China. It is suggested that the trend of monsoonal rainfall in China and India has been attributed to increase in the black carbon and sulphate aerosol. Most of the previous studies assessed the rainfall trend in boreal summer mean. Meanwhile, the seasonal march of the Asian summer monsoon displays a stepwise northward and northeastward migration of rainfall with abrupt onset during boreal spring and summer. Because of large seasonal variability, the long-term trend of the Asian monsoon would exhibit seasonally dependent features which we have to take a consideration of. Here, we analyze the trend of the Asian monsoon rainfall, wind circulation and water vapor flux during 1979-2008 on a monthly mean basis to clarify its seasonality. The transition phase from boreal spring to summer is specially focused. Significant increasing rainfall trend in May is remarkable over the Asian Sea, Bay of Bengal and southeastern monsoon region, which corresponds to advanced monsoon onset in recent decades. The trends are, however, nearly reversed in June over the abovementioned region. Of interest is that the Asian monsoonal rainfall in July and August does not show clear significant trend. Thus, the Asian monsoon has significant trend during the transient phase from boreal spring to summer in particular. The advanced monsoon onset and weakening of the monsoon during early summer are most likely to be attributed to the heat contrast between the Asian landmass and the tropical Indian Ocean. The heating trend over the Asian landmass contributes to the heat contrast variability, because of the persistent SST increase in the Indian Ocean throughout the season. Warming trends in the mid-upper troposphere over the landmass area in May is suggested to

  10. Autoencoder-based identification of predictors of Indian monsoon

    NASA Astrophysics Data System (ADS)

    Saha, Moumita; Mitra, Pabitra; Nanjundiah, Ravi S.

    2016-10-01

    Prediction of Indian summer monsoon uses a number of climatic variables that are historically known to provide a high skill. However, relationships between predictors and predictand could be complex and also change with time. The present work attempts to use a machine learning technique to identify new predictors for forecasting the Indian monsoon. A neural network-based non-linear dimensionality reduction technique, namely, the sparse autoencoder is used for this purpose. It extracts a number of new predictors that have prediction skills higher than the existing ones. Two non-linear ensemble prediction models of regression tree and bagged decision tree are designed with identified monsoon predictors and are shown to be superior in terms of prediction accuracy. Proposed model shows mean absolute error of 4.5 % in predicting the Indian summer monsoon rainfall. Lastly, geographical distribution of the new monsoon predictors and their characteristics are discussed.

  11. Asian monsoons in a late Eocene greenhouse world

    NASA Astrophysics Data System (ADS)

    Licht, A.; van Cappelle, M.; Abels, H. A.; Ladant, J.-B.; Trabucho-Alexandre, J.; France-Lanord, C.; Donnadieu, Y.; Vandenberghe, J.; Rigaudier, T.; Lécuyer, C.; Terry, D., Jr.; Adriaens, R.; Boura, A.; Guo, Z.; Soe, Aung Naing; Quade, J.; Dupont-Nivet, G.; Jaeger, J.-J.

    2014-09-01

    The strong present-day Asian monsoons are thought to have originated between 25 and 22 million years (Myr) ago, driven by Tibetan-Himalayan uplift. However, the existence of older Asian monsoons and their response to enhanced greenhouse conditions such as those in the Eocene period (55-34 Myr ago) are unknown because of the paucity of well-dated records. Here we show late Eocene climate records revealing marked monsoon-like patterns in rainfall and wind south and north of the Tibetan-Himalayan orogen. This is indicated by low oxygen isotope values with strong seasonality in gastropod shells and mammal teeth from Myanmar, and by aeolian dust deposition in northwest China. Our climate simulations support modern-like Eocene monsoonal rainfall and show that a reinforced hydrological cycle responding to enhanced greenhouse conditions counterbalanced the negative effect of lower Tibetan relief on precipitation. These strong monsoons later weakened with the global shift to icehouse conditions 34 Myr ago.

  12. Anti-correlation of summer/winter monsoons?

    PubMed

    Zhang, De'er; Lu, Longhua

    2007-11-15

    On the basis of the anti-correlation of their palaeoclimatic proxy for the strength of the East Asian winter monsoon from Lake Huguang Maar, China, with stalagmite records of the strength of the summer monsoon, Yancheva et al. claim that the strengths of the summer and winter monsoons are anti-correlated on a decadal timescale. They argue that the summer rainfall deficit during ad 700-900 that they infer from their evidence of a stronger winter monsoon, in conjunction with a Tanros battle, led to the collapse of the Tang dynasty (ad 618-907). Using historical climate records, we show here that most cold winters during ad 700-900 were associated with relatively wet summers, indicating that the strengths of the winter and summer monsoons were not negatively correlated during this period.

  13. Geomorphological survey and remote sensing analysis: a multidisciplinary approach to reconstruct triggering factors of a DSGSD in Maso Corto (South Tyrol, Italy)

    NASA Astrophysics Data System (ADS)

    Amato, Gabriele; Fubelli, Giandomenico; Piccin, Gianluca; Chinellato, Giulia; Iasio, Christian; Mosna, David; Morelli, Corrado

    2015-04-01

    In the Alpine regions, it is essential and urgent to define an improved and specific set of monitoring methods for the evolution of instability phenomena in order to avoid the closure of the installations because of the occurrence of natural calamities and to ensure the safety of citizens. In this context the SloMove Project aims at consolidate know-how of the ordinary monitoring applications of surface movements, evaluate their pros and cons and optimize the expected technical procedures of investigation. Within the SloMove project, an experimental composite monitoring has been carried out in the touristic site of Maso Corto (South Tyrol, Italy). Structural-Geomorphological Survey, GPS measurements and Time series analysis of SAR Interferometry data have been integrated. The purposes of this experiment are: 1) to reconstruct the geomorphological dynamics and their state of activity; 2) to provide considerations on the role of permafrost as an influential factor for landslide activity. Structural-Geomorphological survey highlighted control of structural asset of the outcropping lithologies on geomorphological markers, such as trenches, counterscarps, outcropping sliding surfaces. The area is characterized by metamorphic rocks, affected by foliation oriented between N350 and N30. Moreover, joints due to frost thaw activity are common in the shallow portions and the presence of two sets of tectonics fractures (N45, 45°-60° and N360, sub-vertical) has been recognized. In order to evaluate the state of permafrost, rock glaciers in the area have been investigated. SAR interferometry data have been processed by TRE® through the SqueeSAR™ analysis using Radarsat and Envisat images acquired during a period between 2003 and 2009. GPS surveys were carried out through the technique of Rapid-Static Relative Positioning during the summer months of 2012 and 2013. Data shows that an area of 2km2, north of Maso Corto, is affected by a Deep Seated Gravitational Slide

  14. Geochemical evidence of multistage retrogressive failure during the 160,000ka Icod landslide from turbidite facies analysis: multidisciplinary investigative approaches using destructive and non-destructive methodologies

    NASA Astrophysics Data System (ADS)

    Hunt, James; Wynn, Russell; Masson, Doug; Croudace, Ian

    2010-05-01

    The study of modern deep-sea systems through targeted piston coring has enabled detailed investigations into the process mechanics of turbidity currents. In complex systems such as the Moroccan Turbidite System the derivation of provenance is of vital importance, since flows from different sources in this system have been found to behave differently. Early provenance studies in the Madeira Abyssal Plain found that bulk sand-fraction geochemical analysis through ICP-AES could enable successful attribution of provenance to specific turbidites alongside electron microprobe analysis (de Lange, Jarvis & Kuijpers, 1987; Pearce & Jarvis, 1992). These sources including the Moroccan siliclastic shelf, Tenerife, Las Palma, El Hierro and Madeira. ICP-AES, MC-ICP-MS and XRF have been utilised here, however these present destructive methodologies, using 0.1-5g of material >63µm. Deep-sea piston cores are also expensive to collect, and often there is not enough material to remove for analysis without compromising the core. Furthermore, routine sampling, preparation and analysis using the destructive methods stated above are undertaken at considerable cost and analytical time. The successful use of non-destructive instruments to yield quantitative geochemical has become paramount at the NOC. This presentation serves to show the successful application of the TM-1000 tabletop SEM EDS analyser, ITRAX micro-XRF analyser and the GEOTEK XYZ logger, in coincidence with traditional destructive methods. These instruments can only supply semi-quantitative data, unless correct calibration can be achieved, and will be shown here. The 160,000ka Icod landslide from Tenerife generated a 150km3 debris avalanche with a runout of 105km and a >180km3 turbidity, which will form the case study for application of these instruments. The vertically stacked subunit facies of the Icod turbidite has been attributed to generation from a multistage retrogressive failure (Wynn & Masson, 2003). Here there

  15. Comparison of East Asian winter monsoon indices

    NASA Astrophysics Data System (ADS)

    Hui, Gao

    2007-04-01

    Four East Asian winter monsoon (EAWM) indices are compared in this paper. In the research periods, all the indices show similar interannual and decadal-interdecadal variations, with predominant periods centering in 3-4 years, 6.5 years and 9-15 years, respectively. Besides, all the indices show remarkable weakening trends since the 1980s. The correlation coefficient of each two indices is positive with a significance level of 99%. Both the correlation analyses and the composites indicate that in stronger EAWM years, the Siberian high and the higher-level subtropical westerly jet are stronger, and the Aleutian low and the East Asia trough are deeper. This circulation pattern is favorable for much stronger northwesterly wind and lower air temperature in the subtropical regions of East Asia, while it is on the opposite in weaker EAWM years. Besides, EAWM can also exert a remarkable leading effect on the summer monsoon. After stronger (weaker) EAWM, less (more) summer precipitation is seen over the regions from the Yangtze River valley of China to southern Japan, while more (less) from South China Sea to the tropical western Pacific.

  16. Satellite observations of a monsoon depression

    NASA Technical Reports Server (NTRS)

    Warner, C.

    1984-01-01

    The exploration of a monsoon depression over Burma and the Bay of Bengal is discussed. Aircraft and satellite data were examined, with an emphasis on the Microwave Sounding Unit (MSU) aboard TIROS-N and the Scanning Multichannel Microwave Radiometer (SMMR) aboard Nimbus-7. The structure of the monsoon depression was found to be dominated by cumulus convection. The only systematic large scale behavior discerned was a propagation of the depression westward, and diurnal migration of contours of brightness temperature. These contours in the middle troposphere showed a gradient toward the north with the patterns migrating northward at night. From SMMR and dropwindsonde data, water vapor contents were found to be near 65 mm, increasing to more than 70 mm in the northeast Bay of Bengal. Cloud water contents reached about three mm. Rainfall rates exceeding 5.7 mm/h occurred over a small part of the storm area, while mean rainfall rates in areas of order 20,000 sq km reached approximately 0.5 mm/h. Measured MSU brightness temperatures were reconciled very well with dropwindsonde data and with airborne in situ observations of clouds (by photography) and hydrometeors (by radar). Diffuse scattering was determined to be important in computing brightness temperature.

  17. The Dynamics of Bursts in the Australian Monsoon

    NASA Astrophysics Data System (ADS)

    Reeder, M. J.; Berry, G.

    2015-12-01

    The wet season of the Australian monsoon is characterized by sub-seasonal periods of excessively wet or dry conditions, commonly know as monsoon bursts and breaks. This study is concerned with the synoptic evolution prior to monsoon bursts, which are defined here by abrupt transitions of the area-averaged rainfall over the tropical parts of the Australian continent. There is large variability in the number of monsoon bursts from year-to-year and in the time interval between consecutive monsoon bursts. Reanalysis data are used to construct a lag composite of the sequence of events prior to a monsoon burst. It is found that a burst in the Australian monsoon is preceded by the development of a well-defined extratropical wave packet in the Indian Ocean, which propagates toward the Australian continent in the few days leading up to the onset of heavy rainfall in the tropics. As in the case of previous studies on the monsoon onset, the extratropical disturbances propagate equatorward over the Australian continent. These extratropical systems are accompanied by lower tropospheric air mass boundaries, which also propagate into low latitudes. Ahead of these boundaries, relatively warm moist air is advected from the surrounding oceans, locally increasing the convective available potential energy. Commonly employed climate indices shows that monsoon bursts are more likely to occur when the active phase of the Madden-Julian Oscillation is in the vicinity of Australia. Neither the El-Nino Southern Oscillation nor Southern Annular Mode have a significant effect on the occurrence of monsoon bursts.

  18. Does Aerosol Weaken or Strengthen the South Asian Monsoon?

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.

    2007-01-01

    Aerosols are known to have the ability to block off solar radiation reaching the earth surface, causing it to cool - the so-called solar dimming (SDM) effect. In the Asian monsoon region, the SDM effect by aerosol can produce differential cooling at the surface reducing the meridional thermal contrast between land and ocean, leading to a weakening of the monsoon (Ramanathan et al. 2005). On the other hand, absorbing aerosols such as black carbon and dust, when forced up against the steep slopes of the southern Tibetan Plateau can produce upper tropospheric heating, and induce convection-dynamic feedback leading to an advance of the rainy season over northern India and an enhancement of the South Asian monsoon through the "Elevated Heat Pump" (EHP) effect (Lau et al. 2006). In this paper, we present modeling results showing that in a coupled ocean-atmosphere-land system in which concentrations of greenhouse gases are kept constant, the response of the South Asian monsoon to dust and black carbon forcing is the net result of the two opposing effects of SDM and EHP. For the South Asian monsoon, if the increasing upper tropospheric thermal contrast between the Tibetan Plateau and region to the south spurred by the EHP overwhelms the reduction in surface temperature contrast due to SDM, the monsoon strengthens. Otherwise, the monsoon weakens. Preliminary observations are consistent with the above findings. We find that the two effects are strongly scale dependent. On interannual and shorter time scales, the EHP effect appears to dominate in the early summer season (May-June). On decadal or longer time scales, the SDM dominates for the mature monsoon (July-August). Better understanding the physical mechanisms underlying the SDM and the EHP effects, the local emission and transport of aerosols from surrounding deserts and arid-regions, and their interaction with monsoon water cycle dynamics are important in providing better prediction and assessment of climate change

  19. Does Aerosol Weaken or Strengthen the South Asian Monsoon?

    NASA Technical Reports Server (NTRS)

    Lau, William K.

    2010-01-01

    Aerosols are known to have the ability to block off solar radiation reaching the earth surface, causing it to cool - the so-called solar dimming (SDM) effect. In the Asian monsoon region, the SDM effect by aerosol can produce differential cooling at the surface reducing the meridional thermal contrast between land and ocean, leading to a weakening of the monsoon. On the other hand, absorbing aerosols such as black carbon and dust, when forced up against the steep slopes of the southern Tibetan Plateau can produce upper tropospheric heating, and induce convection-dynamic feedback leading to an advance of the rainy season over northern India and an enhancement of the South Asian monsoon through the "Elevated Heat Pump" (EHP) effect. In this paper, we present modeling results showing that in a coupled ocean-atmosphere-land system in which concentrations of greenhouse gases are kept constant, the response of the South Asian monsoon to dust and black carbon forcing is the net result of the two opposing effects of SDM and EHP. For the South Asian monsoon, if the increasing upper tropospheric thermal contrast between the Tibetan Plateau and region to the south spurred by the EHP overwhelms the reduction in surface temperature contrast due to SDM, the monsoon strengthens. Otherwise, the monsoon weakens. Preliminary observations are consistent with the above findings. We find that the two effects are strongly scale dependent. On interannual and shorter time scales, the EHP effect appears to dominate in the early summer season (May-June). On decadal or longer time scales, the SDM dominates for the mature monsoon (July-August). Better understanding the physical mechanisms underlying the SDM and the EHP effects, the local emission and transport of aerosols from surrounding deserts and arid-regions, and their interaction with monsoon water cycle dynamics are important in providing better prediction and assessment of climate change impacts on precipitation of the Asian monsoon

  20. Multidisciplinary Environments: A History of Engineering Framework Development

    NASA Technical Reports Server (NTRS)

    Padula, Sharon L.; Gillian, Ronnie E.

    2006-01-01

    This paper traces the history of engineering frameworks and their use by Multidisciplinary Design Optimization (MDO) practitioners. The approach is to reference papers that have been presented at one of the ten previous Multidisciplinary Analysis and Optimization (MA&O) conferences. By limiting the search to MA&O papers, the authors can (1) identify the key ideas that led to general purpose MDO frameworks and (2) uncover roadblocks that delayed the development of these ideas. The authors make no attempt to assign credit for revolutionary ideas or to assign blame for missed opportunities. Rather, the goal is to trace the various threads of computer architecture and software framework research and to observe how these threads contributed to the commercial framework products available today.

  1. Multidisciplinary investigation of an unusual apparent homicide/suicide.

    PubMed

    Harding, Brett E; Sullivan, Linda M; Adams, Susan; Middleberg, Robert A; Wolf, Barbara C

    2011-09-01

    The investigation of deaths of individuals whose bodies are decomposed, mummified, or skeletonized is particularly difficult for medical examiners and medicolegal death investigators. Determination of the cause and manner of death in such cases frequently requires consultation with experts in a variety of disciplines in the forensic sciences and necessitates correlation of the autopsy results, scene investigation, medical and social history of the deceased, and laboratory studies. The authors report an unusual case of an apparent homicide/suicide involving 2 individuals and a canine that went undetected for almost 4 years. Determination of the cause and manner of death in these cases involved a multidisciplinary, intercontinental investigation and necessitated the performance of toxicologic studies on specimens not commonly analyzed. These cases illustrate the importance of the multidisciplinary approach to medicolegal death investigations and the necessity of considering nontraditional sources of potential information and specimens for laboratory analysis in selected cases.

  2. Supporting multidisciplinary science within NASA's discipline data systems

    NASA Technical Reports Server (NTRS)

    Preheim, Larry E.

    1993-01-01

    Many current and future NASA and non-NASA missions are focusing on multidisciplinary science. The current paradigm for data identification and effective use by the NASA science community is based on the CODMAC model proposed in 1986. As multidisciplinary investigations become more prevalent, many existing systems and the newly developing systems will have to augment the current data identification and access strategies and tools and form alliances with other data systems to provide the broad range of data required. This paper describes the current paradigm, surveys and characterizes, within that paradigm, efforts to develop new access methods and data analysis and visualization tools, identifies additional areas of research not adequately addressed and recommends a further plan of action.

  3. Instruction of Multidisciplinary Content in Introductory Courses

    NASA Astrophysics Data System (ADS)

    Shaibani, Saami J.

    2017-01-01

    There has been an ever-increasing emphasis on the integration of material in the areas of science, technology, engineering and mathematics during the past decade or so. However, there are two major requirements for accomplishing the effective delivery of such multidisciplinary content in the classroom: having high levels of expertise in all of the subjects; and, having the ability to combine the separate fields in a consistent manner without compromising academic purity. The research reported here involves a teacher with this skill set and it includes an example from kinematics, which is initially explored with standard treatment of concepts in mechanics and then developed with analysis employing algebra. As often happens, the non-trivial nature of the result in this case does not readily allow students to have a sense that the physics-based outcome is correct. This shortfall is remedied by adopting a complementary approach with geometry and calculus, which adds an independent perspective that reassures students by confirming the validity of the original answer. The enhanced quality of instruction achieved with the above methodology produces many benefits, including greater student understanding and more opportunities for active involvement by students in the learning process.

  4. The Role of African topography in the South Asian Monsoon

    NASA Astrophysics Data System (ADS)

    Wei, H. H.; Bordoni, S.

    2014-12-01

    The Somali cross-equatorial jet is estimated to contribute up to half of the mass flux crossing the equator during the Asian monsoon season. Previous studies have argued that the Somali jet is strengthened by the East African Highlands, which act as a wall and accelerate the flow (e.g., Krishnamurti et al. 1976, Sashegyi and Geisler 1987). Besides, observational studies have shown a positive correlation between the strength of the Somali jet and the South Asian Monsoon (SAM) precipitation (e.g., Findlater 1969, Halpern and Woiceshyn 2001). These imply that the existence of the topography would relate to a stronger SAM. However, in a more recent study, Chakraborty et al. (2002) found that if the African topography is removed in a comprehensive general circulation model (GCM), the SAM strengthens. In this study, we use the GFDL AM2.1 GCM to conduct experiments with and without topography in Africa, to further examine its influence on the cross-equatorial Somali jet and the SAM. We find that when the African topography is removed, the SAM precipitation increases, consistent with the results in Chakraborty et al. (2002). Interestingly, our results also show that the cross-equatorial Somali jet does weaken in the absence of the African topography, in agreement with previous studies. The moisture budget shows that the increase in precipitation in the no-African topography experiment is primarily due to stronger wind convergence. The dynamics of the cross-equatorial Somali jet is investigated within the framework of the Potential Vorticity (PV) budget, showing the contribution of the changes in friction and diabatic heating to the circulation as the topography is removed. A backward trajectory analysis is also conducted to further examine the influence of topography on both the material tendencies of the PV budget and trajectories of parcels reaching the Indian subcontinent.

  5. Amplification of the solar signal in the summer monsoon rainband in China by synergistic actions of different dynamical responses

    NASA Astrophysics Data System (ADS)

    Zhao, Liang; Wang, Jingsong; Liu, Haiwen; Xiao, Ziniu

    2017-02-01

    A rainband meridional shift index (RMSI) is defined and used to statistically prove that the East Asian summer monsoon rainband is usually significantly more northward in the early summer of solar maximum years than that of solar minimum years. By applying continuous wavelet transform, cross wavelet transform, and wavelet coherence, it is found that throughout most of the 20th century, the significant decadal oscillations of sunspot number (SSN) and the RMSI are phase-locked and since the 1960s, the SSN has led the RMSI slightly by approximately 1.4 yr. Wind and Eliassen-Palm (EP) flux analysis shows that the decadal meridional oscillation of the June rainband likely results from both a stronger or earlier onset of the tropical monsoon and poleward shift of the subtropical westerly jet in high-solar months of May and June. The dynamical responses of the lower tropical monsoon and the upper subtropical westerly jet to the 11-yr solar cycle transmit bottom-up and top-down solar signals, respectively, and the synergistic actions between the monsoon and the jet likely amplify the solar signal at the northern boundary of the monsoon to some extent.

  6. Quasi-biweekly oscillations of the South Asian monsoon and its co-evolution in the upper and lower troposphere

    NASA Astrophysics Data System (ADS)

    Ortega, Sebastián; Webster, Peter J.; Toma, Violeta; Chang, Hai-Ru

    2017-01-01

    The Upper Tropospheric Quasi-Biweekly Oscillation (UQBW) of the South Asian monsoon is studied using the potential vorticity field on the 370 K isentrope. The UQBW is shown to be a common occurrence in the upper troposphere during the monsoon, and its typical evolution is described. We suggest that the UQBW is a phenomenon of both the middle and tropical latitudes, owing its existence to the presence of the planetary-scale upper-tropospheric monsoon anticyclone. The UQBW is first identified as Rossby waves originating in the northern flank of the monsoon anticyclone. These Rossby waves break when reaching the Pacific Ocean, and their associated cyclonic PV anomalies move southward to the east of Asia and then westward across the Indian Ocean and Africa advected by the monsoon anticyclone. A strong correlation, or co-evolution, between the UQBW and quasi-biweekly oscillations in the lower troposphere (QBW) is also found. In particular, analysis of vertically-integrated horizontal moisture transport, 850 hPa geopotential, and outgoing long-wave radiation show that the UQBW is usually observed at the same time as, and co-evolves with, the lower tropospheric QBW over South Asia. We discuss the nature of the UQBW, and its possible physical link with the QBW.

  7. Role of monsoon intraseasonal oscillation and its interannual variability in simulation of seasonal mean in CFSv2

    NASA Astrophysics Data System (ADS)

    Pillai, Prasanth A.; Aher, Vaishali R.

    2016-12-01

    Intraseasonal oscillation (ISO), which appears as "active" and "break" spells of rainfall, is an important component of Indian summer monsoon (ISM). The present study investigates the potential of new National Centre for Environmental Prediction (NCEP) climate forecast system version 2 (CFSv2) in simulating the ISO with emphasis to its interannual variability (IAV) and its possible role in the seasonal mean rainfall. The present analysis shows that the spatial distribution of CFSv2 rainfall has noticeable differences with observations in both ISO and IAV time scales. Active-break cycle of CFSv2 has similar evolution during both strong and weak years. Regardless of a reasonable El Niño Southern Oscillation (ENSO)-monsoon teleconnection in the model, the overestimated Arabian Sea (AS) sea surface temperature (SST)-convection relationship hinters the large-scale influence of ENSO over the ISM region and adjacent oceans. The ISO scale convections over AS and Bay of Bengal (BoB) have noteworthy contribution to the seasonal mean rainfall, opposing the influence of boundary forcing in these areas. At the same time, overwhelming contribution of ISO component over AS towards the seasonal mean modifies the effect of slow varying boundary forcing to large-scale summer monsoon. The results here underline that, along with the correct simulation of monsoon ISO, its IAV and relationship with the boundary forcing also need to be well captured in coupled models for the accurate simulation of seasonal mean anomalies of the monsoon and its teleconnections.

  8. EMSO: European Multidisciplinary Seafloor Observatory

    NASA Astrophysics Data System (ADS)

    Favali, P.; Partnership, Emso

    2009-04-01

    EMSO, a Research Infrastructure listed within ESFRI (European Strategy Forum on Research Infrastructures) Roadmap), is the European-scale network of multidisciplinary seafloor observatories from the Arctic to the Black Sea with the scientific objective of long-term real-time monitoring of processes related to geosphere/biosphere/hydrosphere interactions. EMSO will enhance our understanding of processes through long time series appropriate to the scale of the phenomena, constituting the new frontier of studying Earth interior, deep-sea biology and chemistry and ocean processes. EMSO will reply also to the need expressed in the frame of GMES (Global Monitoring for Environment and Security) to develop a marine segment integrated in the in situ and satellite global monitoring system. The EMSO development relays upon the synergy between the scientific community and the industry to improve the European competitiveness with respect to countries like USA/Canada, NEPTUNE, VENUS and MARS projects, Taiwan, MACHO project, and Japan, DONET project. In Europe the development of an underwater network is based on previous EU-funded projects since early '90, and presently supported by EU initiatives. The EMSO infrastructure will constitute the extension to the sea of the land-based networks. Examples of data recorded by seafloor observatories will be presented. EMSO is presently at the stage of Preparatory Phase (PP), funded in the EC FP7 Capacities Programme. The project has started in April 2008 and will last 4 years with the participation of 12 Institutions representing 12 countries. EMSO potential will be significantly increased also with the interaction with other Research Infrastructures addressed to Earth Science. 2. IFREMER-Institut Français de Recherche pour l'exploitation de la mer (France, ref. Roland Person); KDM-Konsortium Deutsche Meeresforschung e.V. (Germany, ref. Christoph Waldmann); IMI-Irish Marine Institute (Ireland, ref. Michael Gillooly); UTM-CSIC-Unidad de

  9. EMSO: European Multidisciplinary Seafloor Observatory

    NASA Astrophysics Data System (ADS)

    Favali, Paolo

    2010-05-01

    EMSO, a Research Infrastructure listed within ESFRI (European Strategy Forum on Research Infrastructures) Roadmap (Report 2006, http://cordis.europa.eu/esfri/roadmap.htm), is the European-scale network of multidisciplinary seafloor observatories from the Arctic to the Black Sea with the scientific objective of long-term real-time monitoring of processes related to geosphere/biosphere/hydrosphere interactions. EMSO will enhance our understanding of processes through long time series appropriate to the scale of the phenomena, constituting the new frontier of studying Earth interior, deep-sea biology and chemistry and ocean processes. The development of an underwater network is based on previous EU-funded projects since early '90 and is being supported by several EU initiatives, as the on-going ESONET-NoE, coordinated by IFREMER (2007-2011, http://www.esonet-emso.org/esonet-noe/), and aims at gathering together the Research Community of the Ocean Observatories. In 2006 the FP7 Capacities Programme launched a call for Preparatory Phase (PP) projects, that will provide the support to create the legal and organisational entities in charge of managing the infrastructures, and coordinating the financial effort among the countries. Under this call the EMSO-PP project was approved in 2007 with the coordination of INGV and the participation of other 11 Institutions of 11 countries. The project has started in April 2008 and will last 4 years. The EMSO is a key-infrastructure both for Ocean Sciences and for Solid Earth Sciences. In this respect it will enhance and complement profitably the capabilities of other European research infrastructures such as EPOS, ERICON-Aurora Borealis, and SIOS. The perspective of the synergy among EMSO and other ESFRI Research Infrastructures will be outlined. EMSO Partners: IFREMER-Institut Français de Recherche pour l'exploitation de la mer (France, ref. Roland Person); KDM-Konsortium Deutsche Meeresforschung e.V. (Germany, ref. Christoph

  10. Multidisciplinary Optimization Branch Experience Using iSIGHT Software

    NASA Technical Reports Server (NTRS)

    Padula, S. L.; Korte, J. J.; Dunn, H. J.; Salas, A. O.

    1999-01-01

    The Multidisciplinary Optimization (MDO) Branch at NASA Langley Research Center is investigating frameworks for supporting multidisciplinary analysis and optimization research. An optimization framework call improve the design process while reducing time and costs. A framework provides software and system services to integrate computational tasks and allows the researcher to concentrate more on the application and less on the programming details. A framework also provides a common working environment and a full range of optimization tools, and so increases the productivity of multidisciplinary research teams. Finally, a framework enables staff members to develop applications for use by disciplinary experts in other organizations. Since the release of version 4.0, the MDO Branch has gained experience with the iSIGHT framework developed by Engineous Software, Inc. This paper describes experiences with four aerospace applications: (1) reusable launch vehicle sizing, (2) aerospike nozzle design, (3) low-noise rotorcraft trajectories, and (4) acoustic liner design. All applications have been successfully tested using the iSIGHT framework, except for the aerospike nozzle problem, which is in progress. Brief overviews of each problem are provided. The problem descriptions include the number and type of disciplinary codes, as well as all estimate of the multidisciplinary analysis execution time. In addition, the optimization methods, objective functions, design variables, and design constraints are described for each problem. Discussions on the experience gained and lessons learned are provided for each problem. These discussions include the advantages and disadvantages of using the iSIGHT framework for each case as well as the ease of use of various advanced features. Potential areas of improvement are identified.

  11. Possible shift in the ENSO-Indian monsoon rainfall relationship under future global warming

    PubMed Central

    Azad, Sarita; Rajeevan, M.

    2016-01-01

    EI Nino-Southern Oscillation (ENSO) and Indian monsoon rainfall are known to have an inverse relationship, which we have observed in the rainfall spectrum exhibiting a spectral dip in 3–5 y period band. It is well documented that El Nino events are known to be associated with deficit rainfall. Our analysis reveals that this spectral dip (3–5 y) is likely to shift to shorter periods (2.5–3 y) in future, suggesting a possible shift in the relationship between ENSO and monsoon rainfall. Spectral analysis of future climate projections by 20 Coupled Model Intercomparison project 5 (CMIP5) models are employed in order to corroborate our findings. Change in spectral dip speculates early occurrence of drought events in future due to multiple factors of global warming. PMID:26837459

  12. Possible shift in the ENSO-Indian monsoon rainfall relationship under future global warming.

    PubMed

    Azad, Sarita; Rajeevan, M

    2016-02-03

    EI Nino-Southern Oscillation (ENSO) and Indian monsoon rainfall are known to have an inverse relationship, which we have observed in the rainfall spectrum exhibiting a spectral dip in 3-5 y period band. It is well documented that El Nino events are known to be associated with deficit rainfall. Our analysis reveals that this spectral dip (3-5 y) is likely to shift to shorter periods (2.5-3 y) in future, suggesting a possible shift in the relationship between ENSO and monsoon rainfall. Spectral analysis of future climate projections by 20 Coupled Model Intercomparison project 5 (CMIP5) models are employed in order to corroborate our findings. Change in spectral dip speculates early occurrence of drought events in future due to multiple factors of global warming.

  13. Advances in Multi-disciplinary Interoperability

    NASA Astrophysics Data System (ADS)

    Pearlman, J.; Nativi, S.; Craglia, M.; Huerta, J.; Rubio-Iglesias, J. M.; Serrano, J. J.

    2012-04-01

    The challenge for addressing issues such as climate change, food security or ecosystem sustainability is that they require multi-disciplinary collaboration and the ability to integrate information across scientific domains. Multidisciplinary collaborations are difficult because each discipline has its own "language", protocols and formats for communicating within its community and handling data and information. EuroGEOSS demonstrates the added value to the scientific community and to society of making existing systems and applications interoperable and useful within the GEOSS and INSPIRE frameworks. In 2010, the project built an initial operating capacity of a multi-disciplinary Information System addressing three areas: drought, forestry and biodiversity. It is now furthering this development into an advanced operating capacity (http://www.eurogeoss.eu). The key to this capability is the creation of a broker that supports access to multiple resources through a common user interface and the automation of data search and access using state of the art information technology. EuroGEOSS hosted a conference on information systems and multi-disciplinary applications of science and technology. "EuroGEOSS: advancing the vision of GEOSS" provided a forum for developers, users and decision-makers working with advanced multi-disciplinary information systems to improve science and decisions for complex societal issues. In particular, the Conference addressed: Information systems for supporting multi-disciplinary research; Information systems and modeling for biodiversity, drought, forestry and related societal benefit areas; and Case studies of multi-disciplinary applications and outcomes. This paper will discuss the major finding of the conference and the directions for future development.

  14. Prediction and monitoring of monsoon intraseasonal oscillations over Indian monsoon region in an ensemble prediction system using CFSv2

    NASA Astrophysics Data System (ADS)

    Abhilash, S.; Sahai, A. K.; Borah, N.; Chattopadhyay, R.; Joseph, S.; Sharmila, S.; De, S.; Goswami, B. N.; Kumar, Arun

    2014-05-01

    An ensemble prediction system (EPS) is devised for the extended range prediction (ERP) of monsoon intraseasonal oscillations (MISO) of Indian summer monsoon (ISM) using National Centers for Environmental Prediction Climate Forecast System model version 2 at T126 horizontal resolution. The EPS is formulated by generating 11 member ensembles through the perturbation of atmospheric initial conditions. The hindcast experiments were conducted at every 5-day interval for 45 days lead time starting from 16th May to 28th September during 2001-2012. The general simulation of ISM characteristics and the ERP skill of the proposed EPS at pentad mean scale are evaluated in the present study. Though the EPS underestimates both the mean and variability of ISM rainfall, it simulates the northward propagation of MISO reasonably well. It is found that the signal-to-noise ratio of the forecasted rainfall becomes unity by about 18 days. The potential predictability error of the forecasted rainfall saturates by about 25 days. Though useful deterministic forecasts could be generated up to 2nd pentad lead, significant correlations are found even up to 4th pentad lead. The skill in predicting large-scale MISO, which is assessed by comparing the predicted and observed MISO indices, is found to be ~17 days. It is noted that the prediction skill of actual rainfall is closely related to the prediction of large-scale MISO amplitude as well as the initial conditions related to the different phases of MISO. An analysis of categorical prediction skills reveals that break is more skillfully predicted, followed by active and then normal. The categorical probability skill scores suggest that useful probabilistic forecasts could be generated even up to 4th pentad lead.

  15. Influence of Aerosols on Monsoon Circulation and Hydroclimate

    NASA Technical Reports Server (NTRS)

    Lau, William K.

    2006-01-01

    Long recognized as a major environmental hazard, aerosol is now known to have strong impacts on both regional and global water cycles and climate change. In the Asian monsoon regions, the response of the regional water cycle and climate to aerosol forcing is very complex, not only because of presence of diverse mix of aerosol species with vastly different radiative properties, but also because the monsoon is strongly influenced by ocean and land surface processes, land use, land change, as well as regional and global greenhouse warming effects. Thus, sorting out the impacts of aerosol forcing, and interaction with the monsoon water cycle is a very challenging problem. Up to now, besides the general notion that aerosols may significantly impact monsoon through altering large scale radiative heating gradients, there has been very little information regarding the specific signatures, and mechanisms of aerosol-monsoon water cycle interaction. In this talk, based on preliminary results from observations and climate model experiments, I will offer some insights into how aerosols may impact the Asian monsoon water cycle, in particular the effects of absorbing aerosols (dust and black carbon), and the role of the Tibetan Plateau. The influence of aerosol forcing relative to those due to sea surface temperature and land surface processes, and impact on potential predictability of the monsoon climate system will also be discussed.

  16. Influence of Aerosols on Monsoon Circulation and Hydroclimate

    NASA Technical Reports Server (NTRS)

    Lau, William K.M.

    2007-01-01

    Long recognized as a major environmental hazard, aerosol is now known to have strong impacts on both regional and global water cycles and climate change. In the Asian monsoon regions, the response of the regional water cycle and climate to aerosol forcing is very complex, not only because of presence of diverse mix of aerosol species with vastly different radiative properties, but also because the monsoon is strongly influenced by ocean and land surface processes, land use, land change, as well as regional and global greenhouse warming effects. Thus, sorting out the impacts of aerosol forcing, and interaction with the monsoon water cycle is a very challenging problem. Up to now, besides the general notion that aerosols may significantly impact monsoon through altering large scale radiative heating gradients, there has been very little information regarding the specific signatures, and mechanisms of aerosol-monsoon water cycle interaction. In this talk, based on preliminary results from observations and climate model experiments, I will offer some insights into how aerosols may impact the Asian monsoon water cycle, in particular the effects of absorbing aerosols (dust and black carbon), and the role of the Tibetan Plateau. The influence of aerosol forcing relative to those due to sea surface temperature and land surface processes, and impact on potential predictability of the monsoon climate system will also be discussed.

  17. Multi-disciplinary coupling effects for integrated design of propulsion systems

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Singhal, S. N.

    1993-01-01

    Effective computational simulation procedures are described for modeling the inherent multi-disciplinary interactions which govern the accurate response of propulsion systems. Results are presented for propulsion system responses including multi-disciplinary coupling effects using coupled multi-discipline thermal, structural, and acoustic tailoring; an integrated system of multi-disciplinary simulators; coupled material behavior/fabrication process tailoring; sensitivities using a probabilistic simulator; and coupled materials, structures, fracture, and probabilistic behavior simulator. The results demonstrate that superior designs can be achieved if the analysis/tailoring methods account for the multi-disciplinary coupling effects. The coupling across disciplines can be used to develop an integrated coupled multi-discipline numerical propulsion system simulator.

  18. Partitioned Analysis for Multidisciplinary Problems Involving Structures.

    DTIC Science & Technology

    1986-04-30

    ATTN: R FRANK JOINT STRAT TGT PLANNING STAFF BDM CORP ATTN: JK (ATTN: DNA REP) ATTN: F LEECH LAWRENCE LIVERMORE NATIONAL LABORATORY BDM CORPORATION...KAMAN SCIENCES CORPATTN: LIBRARY/B. KINSLOW AIR FORCE INSTITUTE OF TECHNOLOGY/EN KAMAN SCIENCES CORPORATION ATTN: LIBRARY/AFIT/LDEE ATTN: DASIAC AIR

  19. Exergy Based Methods for Multidisciplinary Analysis & Design

    DTIC Science & Technology

    2011-05-01

    STABILITY Properties of Numerical Solution 35 SLT for the Global Domain Essence of the second law is concavity. Equality holds iff...of SLT Expand MSV relative to mean     22 2 qqqq  SS From TSE near equilibrium, Conjecture:     2 0 22 qqqq KSS  222 qqqq...00 qKK 38 Stability Implications of SLT Scaling constant determined from initial conditions. If SLT satisfied locally, then also

  20. Land-surface processes and monsoon climate system

    NASA Astrophysics Data System (ADS)

    Xue, Y.

    2014-12-01

    Differential thermal heating of land and ocean and heat release into the atmosphere are important factors that determine the onset, strength, duration and spatial distribution of large-scale monsoons. A global and seasonal assessment of land surface process (LSP) effects on the monsoon system has been made based on general circulation models (GCM) coupled to different benchmark land models, which physically represent either comprehensive, or partial, or minimal LSP representations. Observed precipitation is applied as constrain and differences in simulation error are used to assess the effect of the LSP with different complexity. The AGCM results indicate that the land/atmosphere interaction has substantial impact on global water cycle, while the monsoon regions have had strongest impact at intraseasonal to decadal scales. Among monsoon regions, West Africa, South Asia, East Asia, and Amazon regions have largest impact while some monsoon regions have less impact due to strong air/sea interactions and narrow land mass. LSP reduces the annual precipitation error by 58% over global monsoon regions, about 35% observed precipitation. The partial LSP effect (excluding soil moisture and vegetation albedo) reduces annual precipitation error over monsoon region that equals to about 13% of observed precipitation. It has also been suggested that LSP contribute to the abrupt jump in latitude of the East Asian monsoon as well as general circulation turning in some monsoon regions in its early stages. The LSP effects have also been assessed in the land use land cover change experiment. Based on recently compiled global land-use data from 1948-2005, the GCM simulation results indicate the degradation in Mexico, West Africa, south and East Asia and South America produce substantial precipitation anomalies, some of which are consistent with observed regional precipitation anomalies. More comprehensive studies with multi-models are imperatively necessary.

  1. Book Review: Late Cenozoic Climate Change in Asia: Loess, Monsoon and Monsoon-arid Environment Evolution

    NASA Astrophysics Data System (ADS)

    Clemens, Steven C.

    2015-01-01

    Loess-Paleosol deposits drape >500,000 km2 of eastern China, spanning environments from the humid, monsoon-influenced regions near the coast to the arid, westerlies-dominated regions inland. Sections, up to hundreds of meters thick, are exposed in deeply incised river valleys and can be accessed as well by drilling. Combined, the high sedimentation rates and extensive geographic coverage make these sections unique among global terrestrial sediment archives. The Chinese loess-paleosol sequences, and the arid interior regions to the northwest, record diverse aspects of geologic and environmental change ranging from the tectonic evolution of the Tibetan Plateau (106 year time scale) through glacial-interglacial scale changes in global ice volume and greenhouse gasses (105 year time scale) on down through the orbital (104 years) to millennial and centennial scale events (103-102 year) relevant to the underpinnings of human interactions with changing environmental pressures. 'Late Cenozoic Climate Chang in Asia: Loess, Monsoon and Monsoon-arid Environment Evolution' is a timely contribution that synthesizes findings derived from the extensive work in these areas, places the findings in the broader context of global climate change and helps to define avenues for future research.

  2. The Aerosol-Monsoon Climate System of Asia

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.; Kyu-Myong, Kim

    2012-01-01

    In Asian monsoon countries such as China and India, human health and safety problems caused by air-pollution are worsening due to the increased loading of atmospheric pollutants stemming from rising energy demand associated with the rapid pace of industrialization and modernization. Meanwhile, uneven distribution of monsoon rain associated with flash flood or prolonged drought, has caused major loss of human lives, and damages in crop and properties with devastating societal impacts on Asian countries. Historically, air-pollution and monsoon research are treated as separate problems. However a growing number of recent studies have suggested that the two problems may be intrinsically intertwined and need to be studied jointly. Because of complexity of the dynamics of the monsoon systems, aerosol impacts on monsoons and vice versa must be studied and understood in the context of aerosol forcing in relationship to changes in fundamental driving forces of the monsoon climate system (e.g. sea surface temperature, land-sea contrast etc.) on time scales from intraseasonal variability (weeks) to climate change ( multi-decades). Indeed, because of the large contributions of aerosols to the global and regional energy balance of the atmosphere and earth surface, and possible effects of the microphysics of clouds and precipitation, a better understanding of the response to climate change in Asian monsoon regions requires that aerosols be considered as an integral component of a fully coupled aerosol-monsoon system on all time scales. In this paper, using observations and results from climate modeling, we will discuss the coherent variability of the coupled aerosol-monsoon climate system in South Asia and East Asia, including aerosol distribution and types, with respect to rainfall, moisture, winds, land-sea thermal contrast, heat sources and sink distributions in the atmosphere in seasonal, interannual to climate change time scales. We will show examples of how elevated

  3. Multidisciplinary management for esophageal and gastric cancer

    PubMed Central

    Boniface, Megan M; Wani, Sachin B; Schefter, Tracey E; Koo, Phillip J; Meguid, Cheryl; Leong, Stephen; Kaplan, Jeffrey B; Wingrove, Lisa J; McCarter, Martin D

    2016-01-01

    The management of esophageal and gastric cancer is complex and involves multiple specialists in an effort to optimize patient outcomes. Utilizing a multidisciplinary team approach starting from the initial staging evaluation ensures that all members are in agreement with the plan of care. Treatment selection for esophageal and gastric cancer often involves a combination of chemotherapy, radiation, surgery, and palliative interventions (endoscopic and surgical), and direct communication between specialists in these fields is needed to ensure appropriate clinical decision making. At the University of Colorado, the Esophageal and Gastric Multidisciplinary Clinic was created to bring together all experts involved in treating these diseases at a weekly conference in order to provide patients with coordinated, individualized, and patient-centered care. This review details the essential elements and benefits of building a multidisciplinary program focused on treating esophageal and gastric cancer patients. PMID:27217796

  4. Multidisciplinary Approach to Linear Aerospike Nozzle Optimization

    NASA Technical Reports Server (NTRS)

    Korte, J. J.; Salas, A. O.; Dunn, H. J.; Alexandrov, N. M.; Follett, W. W.; Orient, G. E.; Hadid, A. H.

    1997-01-01

    A model of a linear aerospike rocket nozzle that consists of coupled aerodynamic and structural analyses has been developed. A nonlinear computational fluid dynamics code is used to calculate the aerodynamic thrust, and a three-dimensional fink-element model is used to determine the structural response and weight. The model will be used to demonstrate multidisciplinary design optimization (MDO) capabilities for relevant engine concepts, assess performance of various MDO approaches, and provide a guide for future application development. In this study, the MDO problem is formulated using the multidisciplinary feasible (MDF) strategy. The results for the MDF formulation are presented with comparisons against sequential aerodynamic and structural optimized designs. Significant improvements are demonstrated by using a multidisciplinary approach in comparison with the single- discipline design strategy.

  5. Multidisciplinary Approach to Aerospike Nozzle Design

    NASA Technical Reports Server (NTRS)

    Korte, J. J.; Salas, A. O.; Dunn, H. J.; Alexandrov, N. M.; Follett, W. W.; Orient, G. E.; Hadid, A. H.

    1997-01-01

    A model of a linear aerospike rocket nozzle that consists of coupled aerodynamic and structural analyses has been developed. A nonlinear computational fluid dynamics code is used to calculate the aerodynamic thrust, and a three-dimensional finite-element model is used to determine the structural response and weight. The model will be used to demonstrate multidisciplinary design optimization (MDO) capabilities for relevant engine concepts, assess performance of various MDO approaches, and provide a guide for future application development. In this study, the MDO problem is formulated using the multidisciplinary feasible (MDF) strategy. The results for the MDF formulation are presented with comparisons against separate aerodynamic and structural optimized designs. Significant improvements are demonstrated by using a multidisciplinary approach in comparison with the single-discipline design strategy.

  6. Linkages of Remote Sea Surface Temperatures and Atlantic Tropical Cyclone Activity Mediated by the African Monsoon

    SciTech Connect

    Taraphdar, Sourav; Leung, Lai-Yung R.; Hagos, Samson M.

    2015-01-28

    Warm sea surface temperatures (SSTs) in North Atlantic and Mediterranean (NAMED) can influence tropical cyclone (TC) activity in the tropical East Atlantic by modulating summer convection over western Africa. Analysis of 30 years of observations show that the NAMED SST is linked to a strengthening of the Saharan heat low and enhancement of moisture and moist static energy in the lower atmosphere over West Africa, which favors a northward displacement of the monsoonal front. These processes also lead to a northward shift of the African easterly jet that introduces an anomalous positive vorticity from western Africa to the main development region (50W–20E; 10N–20N) of Atlantic TC. By modulating multiple processes associated with the African monsoon, this study demonstrates that warm NAMED SST explains 8% of interannual variability of Atlantic TC frequency. Thus NAME SST may provide useful predictability for Atlantic TC activity on seasonal-to-interannual time scale.

  7. Influence of radiative heating and cumulus convection on development of mean monsoon circulation in July

    NASA Technical Reports Server (NTRS)

    Kuo, H. L.; Qian, Y. F.; Chen, Y. J.

    1983-01-01

    Numerical simulations of July mean monsoon circulation in the tropics are described. The model used in the simulations was based on a series of primitive equations for the combined effects of variations of solar radiation, radiative diurnal warming, and large-scale and deep cumulus condensation, and the kinematic effects of topography. The initial states of the model were derived from the observed mean distributions of pressure and humidity. Analysis of the numerical results showed that the large-scale features of the mean July monsoon circulation in the tropics are created mainly by differential diabatic heating under the influence of the specific topography. The time necessary to establish the large scale features was only about 5 days when the diurnal variation of solar radiation was taken into account. Graphic illustrations of the simulated mean July flow conditions are provided.

  8. A 16 ka lacustrine 18O record from High Himalaya reflecting the Indian Monsoon variability

    NASA Astrophysics Data System (ADS)

    Zech, M.; Tuthorn, M.; Zech, R.; Schlütz, F.; Zech, W.; Glaser, B.

    2012-04-01

    Establishing 18O records using organic matter of lake sediments is so far complicated due to analytical challenges. Based on the results obtained by a novel analytical method, the so-called compound-specific delta18O-analysis of hemicellulose monosaccharides (Zech, M. and Glaser, B., 2009. Rapid Communications in Mass Spectrometry 23, 3522-3532), we here present a first well-dated continuous late glacial lacustrine 18O record from High Himalayan lake sediments. Our 18O record, which reflects a coupled hydrological and thermal control, reveals the late glacial Indian Summer Monsoon variability depicting the Bölling/Alleröd and the Younger Dryas. Thus, it closely resembles the 18O records of South Asian speleothems and Greenland ice cores. We hence conclude that our novel 18O method enables regional paleoclimate reconstructions and that our 18O record highlights the previously suggested teleconnections between the Indian and the East Asian Monsoon and Greenland temperatures.

  9. Proxy evidence for China's monsoon precipitation response to volcanic aerosols over the past seven centuries

    NASA Astrophysics Data System (ADS)

    Zhuo, Zhihong; Gao, Chaochao; Pan, Yuqing

    2014-06-01

    The effect of volcanic aerosols on China's monsoon precipitation over the past 700 years has been studied using two independently compiled histories of volcanism combined with the Monsoon Asia Drought Atlas. For both reconstructions, four categories of eruptions are distinguished based on the character of their Northern Hemisphere (NH) injection; then Superposed Epoch Analysis (SEA) with a 10,000 Monte Carlo resampling procedure is undertaken for each category and also each individual grid. Results show a statistically significant (at 90% confidence level) drying trend over mainland China from year 1 to year 4 after the eruptions, and the more sulfate aerosol that is injected into the NH stratosphere, the more severe this drying trend. In comparison, a minor wetting trend is observed in the years following Southern Hemisphere-only injections. Results from spatial distribution of the SEA show (1) a southward movement of the significant dry areas in eastern China from year 0 to year 2 after volcanic perturbations that are either equal to or double the size of the 1991 Mount Pinatubo eruption (15 T sulfate aerosols in NH) and (2) northeast and northwest China experienced substantial droughts in years 2 to 5. These results are in good agreement with a SEA analysis of the Chinese Historical Drought Disaster Index compiled from historical meteorological records. Our findings illustrate the important role stratospheric aerosols have played in altering China's precipitation during the summer monsoon season and can shed new light on the possible effects that stratospheric geoengineering may have on China's precipitation.

  10. Southern Indian Ocean SST as a modulator for the progression of Indian summer monsoon

    NASA Astrophysics Data System (ADS)

    Shahi, Namendra Kumar; Rai, Shailendra; Mishra, Nishant

    2016-11-01

    This study explores the possibility of southern Indian Ocean (SIO) sea surface temperature (SST) as a modulator for the early phase of Indian summer monsoon and its possible physical mechanism. A dipole-like structure is obtained from the empirical orthogonal function (EOF) analysis which is similar to an Indian Ocean subtropical dipole (IOSD) found earlier. A subtropical dipole index (SDI) is defined based on the SST anomaly over the positive and negative poles. The regression map of rainfall over India in the month of June corresponding to the SDI during 1983-2013 shows negative patterns along the Western Ghats and Central India. However, the regression pattern is insignificant during 1952-1982. The multiple linear regression models and partial correlation analysis also indicate that the SDI acts as a dominant factor to influence the rainfall over India in the month of June during 1983-2013. The similar result is also obtained with the help of composite rainfall over the land points of India in the month of June for positive (negative) SDI events. It is also observed that the positive (negative) SDI delays (early) the onset dates of Indian monsoon over Kerala during the time domain of our study. The study is further extended to identify the physical mechanism of this impact, and it is found that the heating (cooling) in the region covering SDI changes the circulation pattern in the SIO and hence impacts the progression of monsoon in India.

  11. Multi-Scale Interactions Associated with the Monsoon Onset Over South China Sea and Adjacent Regions during SCSMEX-98

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.; Li, X.; Wu, H.-T.

    1999-01-01

    Using data collected during The South China Sea Monsoon Experiment (SCSMEX) (1998) as well as from the TRMM Microwave-Imager (TMI) and precipitation radar (PR), we have studied the multi-scale interactions (meso-synoptic-intraseasonal) associated with monsoon onset over South China Sea (SCS) and its subsequent evolution. Results show that the monsoon onset (defined by development of steady wind direction and heavy precipitation) over the northern SCS occurred around May 15 -17. Prevailing southerlies and southwesterlies developed over the central SCS after May 20. Shortly after, monsoon convection developed over the whole SCS region around May 23-27. The entire onset process appeared to be delayed by about a week to 10 days compared with climatology. During late spring of 1998, mid-latitude frontal systems were particularly active. These systems strongly impacted the northern SCS convection and may have been instrumental in triggering the onset of the SCS monsoon. The Tropical Oceans and Global Atmosphere (TOGA) and Bureau of Meteorology Research Centre (BMRC) radar showed a wide variety of convective systems over the Intensive Flux Array, from frontal bands to shear-banded structure, deep convection, pop-corn type shallow convection, slow moving "fine lines" to water spout. Analysis of SSM/I wind and moisture data suggested that the delayed convective activity over the SCS may be linked to the weakened northward propagation of monsoon rain band, hence contributing to a persistence of the rainband south of the Yangtze River and the disastrous flood that occurred over this region during mid to late June, 1998.

  12. The Role of Stratiform and Convective heating in modifying the northward phase propagation of Monsoon Intraseasonal Oscillation

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, R.; Goswami, B.; Sahai, A. K.

    2009-12-01

    In this study, contribution of stratiform and convective rain rate to total rain rate during different phases of the northward propagating boreal summer monsoon Intraseasonal Oscillation (ISO) is brought out using the TRMM data. Two new insights have emerged from this analysis as shown in Fig.1. It may be noted from Fig.1 that the convective component seems to grow and decay in situ during evolution of active/break phases, the northward propagation of the monsoon ISO is contributed by organized movement of the stratiform component. Further, the trade mark meridional dipole pattern of total rainfall between monsoon trough zone (MTZ) and equatorial Indian Ocean (EIO) also arises largely from contribution stratiform anomalies. The northward propagation of the monsoon intraseasonal oscillation is known to be due to the anomalous response of the atmosphere to heating in the presence of mean easterly vertical shear. Modification of vertical profile of heating due to contribution from stratiform rain could influence the northward propagation of monsoon ISO. We test this using a simple dynamical model known as PUMA (Portable Unified Model of Atmosphere) developed by University of Hamburg, Germany to study the response of the ‘convective’ and ‘stratiform’ heating profiles on the modification of the mean condition which facilitates the northward propagation. Such modification in the large scale response (e.g. vertical shear, barotropic vorticity) seen clearly to be related with the structure of the heating profile (convective or stratiform). The presence of stratiform heating favors the northward phase propagation of monsoon ISO. These results underline the importance simulating the partitioning of convective and stratiform rain by cumulous parameterization in climate models if they have to get the space-time structure of the summer ISOs correctly. Fig. 1 Figure showing the northward propagation of total (top), convective (middle) and stratiform (bottom) rainrate

  13. Asian Monsoon Changes and the Role of Aerosol and Greenhouse Gas Forcing

    NASA Astrophysics Data System (ADS)

    Ting, M.; Li, X.

    2015-12-01

    Changes in Asian summer (June to August) monsoon in response to aerosol and greenhouse gas forcing are examined using observations and the Coupled Model Intercomparison Project - Phase 5 (CMIP5) multi-model, multi-realization ensemble. Results show that during the historical period, CMIP5 models show a predominantly drying trend in Asian monsoon, while in the 21st Century under representative concentration pathway 8.5 (rcp8.5) scenario, monsoon rainfall enhances across the entire Asian domain. The thermodynamic and dynamic mechanisms causing the changes are evaluated using the moisture budget analysis. The drying trend in the CMIP5 historical simulations and the wetting trend in the rcp8.5 projections can be explained by the relative importance of dynamical and thermodynamical contributions to the total moisture convergence. While thermodynamic mechanism dominates in the future, the historical rainfall changes are dominated by the changes in circulation. The relative contributions of aerosols and greenhouse gases (GHGs) on the historical monsoon change are further examined using CMIP5 single-forcing simulations. Rainfall reduces under aerosol forcing and increases under greenhouse gas (GHG) forcing. Aerosol forcing dominates over the greenhouse effect during the historical period, leading to the general drying trend in the all-forcing simulations. While the thermodynamic change of mean moisture convergence in the all-forcing case is dominated by the GHG forcing, the dynamic change in mean moisture convergence in the all-forcing case is dominated by the aerosol forcing. Further analysis using atmospheric GCM with prescribed aerosol and GHG radiative forcing versus those with the prescribed sea surface temperature (SST) warming suggests that the weak circulation changes due to GHG forcing is a result of the cancellation between CO2 radiative forcing and the SST warming, while aerosol radiative effect tends to enhance the circulation response due to SST forcing.

  14. A Multidisciplinary Course in Bioengineering.

    ERIC Educational Resources Information Center

    Bienkowski, Paul R.; And Others

    1989-01-01

    Outlines a graduate course, "Microbial Systems Analysis," for students in chemical and environmental engineering or engineering mechanics, as well as microbiology, ecology and biotechnology. Describes the objectives, structure and laboratory experiments for the course. (YP)

  15. Multidisciplinary cognitive content of nanoscience and nanotechnology

    NASA Astrophysics Data System (ADS)

    Milojević, Staša

    2012-01-01

    This article examines the cognitive evolution and disciplinary diversity of nanoscience/nanotechnology (nano research) as expressed through the terminology used in titles of nano journal articles. The analysis is based on the NanoBank bibliographic database of 287,106 nano articles published between 1981 and 2004. We perform multifaceted analyses of title words, focusing on 100 most frequent words or phrases (terms). Hierarchical clustering of title terms reveals three distinct time periods of cognitive development of nano research: formative (1981-1990), early (from 1991 to 1998), and current (after 1998). Early period is characterized by the introduction of thin film deposition techniques, while the current period is characterized by the increased focus on carbon nanotube and nanoparticle research. We introduce a method to identify disciplinary components of nanotechnology. It shows that the nano research is being carried out in a number of diverse parent disciplines. Currently, only 5% of articles are published in dedicated nano-only journals. We find that some 85% of nano research today is multidisciplinary. The case study of the diffusion of several nano-specific terms (e.g., "carbon nanotube") shows that concepts spread from the initially few disciplinary components to the majority of them in a time span of around a decade. Hierarchical clustering of disciplinary components reveals that the cognitive content of current nanoscience can be divided into nine clusters. Some clusters account for a large fraction of nano research and are identified with such parent disciplines as the condensed matter and applied physics, materials science, and analytical chemistry. Other clusters represent much smaller parts of nano research, but are as cognitively distinct. In the decreasing order of size, these fields are: polymer science, biotechnology, general chemistry, surface science, and pharmacology. Cognitive content of research published in nano-only journals is the

  16. GPM Sees Slow Start of India's 2015 Monsoon Season

    NASA Video Gallery

    This animation shows the GPM core observatory total rainfall that fell from June 1 to 8. 2015 at the start of India's Monsoon Season as calculated by Integrated Multi-satellitE Retrievals for GPM (...

  17. Impact of anthropogenic aerosols on Indian summer monsoon

    SciTech Connect

    Wang, Chien; Kim, Dongchul; Ekman, Annica; Barth, Mary; Rasch, Philip J.

    2009-11-05

    Using an interactive aerosol-climate model we find that absorbing anthropogenic aerosols, whether coexisting with scattering aerosols or not, can significantly affect the Indian summer monsoon system. We also show that the influence is reflected in a perturbation to the moist static energy in the sub-cloud layer, initiated as a heating by absorbing aerosols to the planetary boundary layer. The perturbation appears mostly over land, extending from just north of the Arabian Sea to northern India along the southern slope of the Tibetan Plateau. As a result, during the summer monsoon season, modeled convective precipitation experiences a clear northward shift, coincidently in agreement with observed monsoon precipitation changes in recent decades particularly during the onset season. We demonstrate that the sub-cloud layer moist static energy is a useful quantity for determining the impact of aerosols on the northward extent and to a certain degree the strength of monsoon convection.

  18. The effect of Eurasian snow cover on the Indian monsoon

    SciTech Connect

    Vernekar, A.D.; Zhou, J.; Shukla, J.

    1995-02-01

    More than a century ago, Blanford suggested the inverse relation between Himalayan winter and spring snow accumulation and subsequent summer monsoon rainfall over India. This relation was later substantiated with additional data by Walker. Because of an inadequate observational network to obtain the spatial variation of snow cover over the Himalayan region, little progress was made until the availability of satellite measurements. Snow cover data derived from satellite observations was used to show that the correlation between winter Eurasian snow cover south of 52{degrees}N and the following Indian summer monsoon rainfall is negative and statistically significant. This result was further supported by additional research. The relationship between snow cover and monsoon circulation is consistent with a suggestion that the Indian monsoon circulation is a dynamically stable system and its interannual variations are largely determined by slowly varying surface boundary conditions. 64 refs., 22 figs.

  19. Radiative energy budget estimates for the 1979 southwest summer monsoon

    NASA Technical Reports Server (NTRS)

    Ackerman, Steven A.; Cox, Stephen K.

    1987-01-01

    A major objective of the summer monsoon experiment (SMONEX) was the determination of the heat sources and sinks associated with the southwest summer monsoon. The radiative component is presented here. The vertically integrated tropospheric radiation energy budget is negative and varies significantly as a function of monsoon activity. The gradient in the latitudinal mean tropospheric cooling reverses between the winter periods and the late spring/early summer periods. The radiative component of the vertical profile of the diabatic heating is derived. These profiles are a strong function of the stage of the monsoon as well as the geographic region. In general, the surface experiences a net gain of radiative energy during the late spring and early summer periods. During the winter periods, areas northward of 25 N display net surface losses, while the remaining areas exhibit net gains.

  20. Variations in optical properties of aerosols on monsoon seasonal change and estimation of aerosol optical depth using ground-based meteorological and air quality data

    NASA Astrophysics Data System (ADS)

    Tan, F.; Lim, H. S.; Abdullah, K.; Yoon, T. L.; Holben, B.

    2014-07-01

    In this study, the optical properties of aerosols in Penang, Malaysia were analyzed for four monsoonal seasons (northeast monsoon, pre-monsoon, southwest monsoon, and post-monsoon) based on data from the AErosol RObotic NETwork (AERONET) from February 2012 to November 2013. The aerosol distribution patterns in Penang for each monsoonal period were quantitatively identified according to the scattering plots of the aerosol optical depth (AOD) against the Angstrom exponent. A modified algorithm based on the prototype model of Tan et al. (2014a) was proposed to predict the AOD data. Ground-based measurements (i.e., visibility and air pollutant index) were used in the model as predictor data to retrieve the missing AOD data from AERONET because of frequent cloud formation in the equatorial region. The model coefficients were determined through multiple regression analysis using selected data set from in situ data. The predicted AOD of the model was generated based on the coefficients and compared against the measured data through standard statistical tests. The predicted AOD in the proposed model yielded a coefficient of determination R2 of 0.68. The corresponding percent mean relative error was less than 0.33% compared with the real data. The results revealed that the proposed model efficiently predicted the AOD data. Validation tests were performed on the model against selected LIDAR data and yielded good correspondence. The predicted AOD can beneficially monitor short- and long-term AOD and provide supplementary information in atmospheric corrections.

  1. A multidisciplinary team care approach improves outcomes in high-risk pediatric neuroblastoma patients.

    PubMed

    Chang, Hsiu-Hao; Liu, Yen-Lin; Lu, Meng-Yao; Jou, Shiann-Tarng; Yang, Yung-Li; Lin, Dong-Tsamn; Lin, Kai-Hsin; Tzen, Kai-Yuan; Yen, Ruoh-Fang; Lu, Ching-Chu; Liu, Chia-Ju; Peng, Steven Shinn-Forng; Jeng, Yung-Ming; Huang, Shiu-Feng; Lee, Hsinyu; Juan, Hsueh-Fen; Huang, Min-Chuan; Liao, Yung-Feng; Lee, Ya-Ling; Hsu, Wen-Ming

    2017-01-17

    We assessed the impact of a multidisciplinary team care program on treatment outcomes in neuroblastoma patients. Newly diagnosed neuroblastoma patients received treatment under the Taiwan Pediatric Oncology Group (TPOG) N2002 protocol at the National Taiwan University Hospital beginning in 2002. A multidisciplinary team care approach that included nurse-led case management for patients treated under this protocol began in January 2010. Fifty-eight neuroblastoma patients, including 29 treated between 2002 and 2009 (Group 1) and 29 treated between 2010 and 2014 (Group 2), were enrolled in the study. The 5-year overall survival (OS) and event-free survival (EFS) rates for all 58 patients were 59% and 54.7%, respectively. Group 2 patients, who were treated after implementation of the multidisciplinary team care program, had better 3-year EFS (P = 0.046), but not OS (P = 0.16), rates than Group 1 patients. In a multivariate analysis, implementation of the multidisciplinary team approach was the only significant independent prognostic factor for neuroblastoma patients. In further subgroup analyses, the multidisciplinary team approach improved EFS, but not OS, in patients with stage 4 disease, those in the high-risk group, and those with non-MYCN amplified tumors. These data indicate a multidisciplinary team care approach improved survival outcomes in high-risk neuroblastoma patients. However, further investigation will be required to evaluate the long-term effects of this approach over longer follow-up periods.

  2. Development and Application of the Collaborative Optimization Architecture in a Multidisciplinary Design Environment

    NASA Technical Reports Server (NTRS)

    Braun, R. D.; Kroo, I. M.

    1995-01-01

    Collaborative optimization is a design architecture applicable in any multidisciplinary analysis environment but specifically intended for large-scale distributed analysis applications. In this approach, a complex problem is hierarchically de- composed along disciplinary boundaries into a number of subproblems which are brought into multidisciplinary agreement by a system-level coordination process. When applied to problems in a multidisciplinary design environment, this scheme has several advantages over traditional solution strategies. These advantageous features include reducing the amount of information transferred between disciplines, the removal of large iteration-loops, allowing the use of different subspace optimizers among the various analysis groups, an analysis framework which is easily parallelized and can operate on heterogenous equipment, and a structural framework that is well-suited for conventional disciplinary organizations. In this article, the collaborative architecture is developed and its mathematical foundation is presented. An example application is also presented which highlights the potential of this method for use in large-scale design applications.

  3. Asian Summer Monsoon Intraseasonal Variability in General Circulation Models

    SciTech Connect

    Sperber, K R; Annamalai, H

    2004-02-24

    The goals of this report are: (1) Analyze boreal summer Asian monsoon intraseasonal variability general circulation models--How well do the models represent the eastward and northward propagating components of the convection and how well do the models represent the interactive control that the western tropical Pacific rainfall exerts on the rainfall over India and vice-versa? (2) Role of air-sea interactions--prescribed vs. interactive ocean; and (3) Mean monsoon vs. variability.

  4. Land-surface processes and monsoon climate system

    NASA Astrophysics Data System (ADS)

    Xue, Yongkang; De Sales, Fernando; Lau, William; Boone, Arron; Mechoso, Carlos

    2015-04-01

    Yongkang Xue, F. De Sales, B. Lau, A. Boone, C. R. Mechoso Differential thermal heating of land and ocean and heat release into the atmosphere are important factors that determine the onset, strength, duration and spatial distribution of large-scale monsoons. A global and seasonal assessment of land surface process (LSP) effects on the monsoon system has been made based on general circulation models (GCM) coupled to different benchmark land models, which physically represent either comprehensive, or partial, or minimal LSP representations. Observed precipitation is applied as constrain and differences in simulation error are used to assess the effect of the LSP with different complexity. The AGCM results indicate that the land/atmosphere interaction has substantial impact on global water cycle, while the monsoon regions have had strongest impact at intraseasonal to decadal scales. Among monsoon regions, West Africa, South Asia, East Asia, and Amazon regions have largest impact while some monsoon regions have less impact due to strong air/sea interactions and narrow land mass there. LSP reduces the annual precipitation error by 58% over global monsoon regions, about 35% observed precipitation. The partial LSP effect (excluding soil moisture and vegetation albedo) reduces annual precipitation error over monsoon region that equals to about 13% of observed precipitation. The LSP affects the monsoon evolution through different mechanisms at different scales. It affects the surface energy balance and energy partitioning in latent and sensible heat, the atmospheric heating rate, and general circulation. The LSP effects have also been assessed in the land use land cover change experiment. Based on recently compiled global land-use data from 1948-2005, the GCM simulation results indicate the degradation in Mexico, West Africa, south and East Asia and South America produce substantial precipitation anomalies, some of which are consistent with observed regional precipitation

  5. The simulated Indian monsoon: A GCM sensitivity study

    NASA Technical Reports Server (NTRS)

    Fennessy, M. J.; Kinter, J. L., III; Kirtman, B.; Marx, L.; Nigam, S.; Schneider, E.; Shukla, J.; Straus, D.; Vernekar, A.; Xue, Y.

    1994-01-01

    A series of sensitivity experiments are conducted in an attempt to understand and correct deficiencies in the simulation of the seasonal mean Indian monsoon with a global atmospheric general circulation model. The seasonal mean precipitation is less than half that observed. This poor simulation in seasonal integrations is independent of the choice of initial conditions and global sea surface temperature data used. Experiments are performed to test the sensitivity of the Indian monsoon simulation to changes in orography, vegetation, soil, wetness, and cloudiness. The authors find that the deficiency of the model precipitation simulation may be attributed to the use of an enhanced orography in the integrations. Replacement of this orography with a mean orography results in a much more realistic simulation of Indian monsoon circulation and rainfall. Experiments with a linear primitive equation model on the sphere suggest that this striking improvement is due to modulations of the orographically forced waves in the lower troposphere. This improvement in the monsoon simulation is due to the kinematic and dynamical effects of changing the topography, rather than the thermal effects, which were minimal. The magnitude of the impact on the Indian monsoon of the other sensitivity experiments varied considerably, but was consistently less than the impact of using the mean orography. However, results from the soil moisture sensitivity experiments suggest a possibly important role for soil moisture in simulating tropical precipitation, including that associated with the Indian monsoon.

  6. Causal evidence between monsoon and evolution of rhizomyine rodents

    PubMed Central

    López-Antoñanzas, Raquel; Knoll, Fabien; Wan, Shiming; Flynn, Lawrence J.

    2015-01-01

    The modern Asian monsoonal systems are currently believed to have originated around the end of the Oligocene following a crucial step of uplift of the Tibetan-Himalayan highlands. Although monsoon possibly drove the evolution of many mammal lineages during the Neogene, no evidence thereof has been provided so far. We examined the evolutionary history of a clade of rodents, the Rhizomyinae, in conjunction with our current knowledge of monsoon fluctuations over time. The macroevolutionary dynamics of rhizomyines were analyzed within a well-constrained phylogenetic framework coupled with biogeographic and evolutionary rate studies. The evolutionary novelties developed by these rodents were surveyed in parallel with the fluctuations of the Indian monsoon so as to evaluate synchroneity and postulate causal relationships. We showed the existence of three drops in biodiversity during the evolution of rhizomyines, all of which reflected elevated extinction rates. Our results demonstrated linkage of monsoon variations with the evolution and biogeography of rhizomyines. Paradoxically, the evolution of rhizomyines was accelerated during the phases of weakening of the monsoons, not of strengthening, most probably because at those intervals forest habitats declined, which triggered extinction and progressive specialization toward a burrowing existence. PMID:25759260

  7. Causal evidence between monsoon and evolution of rhizomyine rodents.

    PubMed

    López-Antoñanzas, Raquel; Knoll, Fabien; Wan, Shiming; Flynn, Lawrence J

    2015-03-11

    The modern Asian monsoonal systems are currently believed to have originated around the end of the Oligocene following a crucial step of uplift of the Tibetan-Himalayan highlands. Although monsoon possibly drove the evolution of many mammal lineages during the Neogene, no evidence thereof has been provided so far. We examined the evolutionary history of a clade of rodents, the Rhizomyinae, in conjunction with our current knowledge of monsoon fluctuations over time. The macroevolutionary dynamics of rhizomyines were analyzed within a well-constrained phylogenetic framework coupled with biogeographic and evolutionary rate studies. The evolutionary novelties developed by these rodents were surveyed in parallel with the fluctuations of the Indian monsoon so as to evaluate synchroneity and postulate causal relationships. We showed the existence of three drops in biodiversity during the evolution of rhizomyines, all of which reflected elevated extinction rates. Our results demonstrated linkage of monsoon variations with the evolution and biogeography of rhizomyines. Paradoxically, the evolution of rhizomyines was accelerated during the phases of weakening of the monsoons, not of strengthening, most probably because at those intervals forest habitats declined, which triggered extinction and progressive specialization toward a burrowing existence.

  8. Causal evidence between monsoon and evolution of rhizomyine rodents

    NASA Astrophysics Data System (ADS)

    López-Antoñanzas, Raquel; Knoll, Fabien; Wan, Shiming; Flynn, Lawrence J.

    2015-03-01

    The modern Asian monsoonal systems are currently believed to have originated around the end of the Oligocene following a crucial step of uplift of the Tibetan-Himalayan highlands. Although monsoon possibly drove the evolution of many mammal lineages during the Neogene, no evidence thereof has been provided so far. We examined the evolutionary history of a clade of rodents, the Rhizomyinae, in conjunction with our current knowledge of monsoon fluctuations over time. The macroevolutionary dynamics of rhizomyines were analyzed within a well-constrained phylogenetic framework coupled with biogeographic and evolutionary rate studies. The evolutionary novelties developed by these rodents were surveyed in parallel with the fluctuations of the Indian monsoon so as to evaluate synchroneity and postulate causal relationships. We showed the existence of three drops in biodiversity during the evolution of rhizomyines, all of which reflected elevated extinction rates. Our results demonstrated linkage of monsoon variations with the evolution and biogeography of rhizomyines. Paradoxically, the evolution of rhizomyines was accelerated during the phases of weakening of the monsoons, not of strengthening, most probably because at those intervals forest habitats declined, which triggered extinction and progressive specialization toward a burrowing existence.

  9. Evaluating Multidisciplinary Education in Health Care.

    ERIC Educational Resources Information Center

    Pirrie, Anne; Wilson, Valerie; Elsegood, John; Hall, John; Hamilton, Sheila; Harden, Ronald; Lee, Diana; Stead, Joan

    A 2-year study evaluated students' and course organizers' perceptions of the effectiveness of multidisciplinary education (ME) in health care and factors that facilitate or inhibit its development. The study had three phases: a survey of ME provision in the United Kingdom; 42 qualitative interviews and focus groups in 14 sites; and data feedback.…

  10. Acute mesenteric ischemia: current multidisciplinary approach.

    PubMed

    Savlania, Ajay; Tripathi, Ramesh K

    2017-04-01

    The aim of this review was to describe and discuss the mechanisms of acute mesenteric ischemia (AMI) and the rationale and conduct of currently available endovascular and open surgical techniques in its management. We also propose an algorithm to support the current multidisciplinary approach in decision-making for mesenteric revascularization to manage this high-risk entity.

  11. A multidisciplinary approach to improving revenue integrity.

    PubMed

    Craghead, Todd; Liston, Eric

    2014-03-01

    Intermountain Healthcare's journey toward a modern revenue integrity process began with five key steps: building a multidisciplinary team, developing department-specific charge-capture teams, providing ongoing education and training on best practices for revenue integrity, leveraging new technology and business support services, establishing a proactive approach to managing audits and compliance.

  12. Multidisciplinary approaches to climate change questions

    USGS Publications Warehouse

    Middleton, Beth A.; LePage, Ben A.

    2011-01-01

    Multidisciplinary approaches are required to address the complex environmental problems of our time. Solutions to climate change problems are good examples of situations requiring complex syntheses of ideas from a vast set of disciplines including science, engineering, social science, and the humanities. Unfortunately, most ecologists have narrow training, and are not equipped to bring their environmental skills to the table with interdisciplinary teams to help solve multidisciplinary problems. To address this problem, new graduate training programs and workshops sponsored by various organizations are providing opportunities for scientists and others to learn to work together in multidisciplinary teams. Two examples of training in multidisciplinary thinking include those organized by the Santa Fe Institute and Dahlem Workshops. In addition, many interdisciplinary programs have had successes in providing insight into climate change problems including the International Panel on Climate Change, the Joint North American Carbon Program, the National Academy of Science Research Grand Challenges Initiatives, and the National Academy of Science. These programs and initiatives have had some notable success in outlining some of the problems and solutions to climate change. Scientists who can offer their specialized expertise to interdisciplinary teams will be more successful in helping to solve the complex problems related to climate change.

  13. Improving Student Achievement in a Multidisciplinary Context

    ERIC Educational Resources Information Center

    Chapman, Amanda; Bloxham, Sue

    2004-01-01

    This article analyses interim findings of an ongoing action research project into the use of assessment criteria and grade descriptors in the assessment process. The project is multidisciplinary and covers areas as diverse as Sports Sociology, Economics, Youth and Community Studies, and Education. The idea is to equip first-year students with the…

  14. Stronger Disciplinary Identities in Multidisciplinary Research Schools

    ERIC Educational Resources Information Center

    Geschwind, Lars; Melin, Göran

    2016-01-01

    In this study, two multidisciplinary Social Sciences and Humanities research schools in Sweden have been investigated regarding disciplinary identity-making. This study investigates the meetings between different disciplines around a common thematic area of study for Ph.D. students. The Ph.D. students navigate through a complex social and…

  15. Thoughts about multidisciplinary, interdisciplinary, and transdisciplinary research.

    PubMed

    Fawcett, Jacqueline

    2013-10-01

    This essay focuses on multidisciplinary, interdisciplinary, and transdisciplinary research. The definitions and objectives for these three types of multiple discipline research are given. Discussion centers on the gains and losses that may be experienced by individual nurses who engage in such research, as well as gains and losses for the discipline of nursing.

  16. International Multidisciplinary Artificial Gravity (IMAG) Project

    NASA Technical Reports Server (NTRS)

    Laurini, Kathy

    2007-01-01

    This viewgraph presentation reviews the efforts of the International Multidisciplinary Artificial Gravity Project. Specifically it reviews the NASA Exploration Planning Status, NASA Exploration Roadmap, Status of Planning for the Moon, Mars Planning, Reference health maintenance scenario, and The Human Research Program.

  17. Structuring Decision-Making in Multidisciplinary Teams.

    ERIC Educational Resources Information Center

    Kabler, Michael L.; Genshaft, Judy L.

    1983-01-01

    Three areas related to decision making are discussed: (1) a research survey summary of multidisciplinary team decision making (MTD); (2) four approaches for structuring MTD decision making; and (3) styles of leadership as a factor that impacts on the decision-making teams. (Author/PN)

  18. Are Multidisciplinary Teams Worth the Investment?

    ERIC Educational Resources Information Center

    Yoshida, Roland K.

    1983-01-01

    Current research data provide only weak support for the continued use of multidisciplinary teams (MDTs). It is argued that MDTs have not had a fair chance to be implemented and that the complexity of organizational changes needed for MDTs to function effectively have been overlooked by team members and administrators. (Author/PN)

  19. Directions in Environmental Gerontology: A Multidisciplinary Field

    ERIC Educational Resources Information Center

    Kendig, Hal

    2003-01-01

    This article considers developments and directions for environmental gerontology drawing on the three papers in this Forum. The multidisciplinary field came of age during the 1960s with Powell Lawton's powerful environmental press paradigm and its applications to empirical research and building design. Recent theoretical developments in Europe and…

  20. Creating Collaborative Community in Multidisciplinary Settings.

    ERIC Educational Resources Information Center

    Twale, Darla J.; Schaller, Molly A.; Hunley, Sawyer A.; Polanski, Patricia J.

    2002-01-01

    Examined part-time students' perceptions of collaborative community in a graduate, multidisciplinary education department with courses offered on multiple campuses. Found that perceptions of community are synonymous with friendship, involvement, cohesion, communication, and trust. These feelings were affected more by campus location, program area,…

  1. Summer climate of Madagascar and monsoon pulsing of its vortex

    NASA Astrophysics Data System (ADS)

    Jury, Mark R.

    2016-02-01

    This study analyzes the climate of Madagascar (12°-26°S, 43°-50°E) and its relation to the Indian Ocean during austral summer (Dec-Mar). Moisture converges onto a standing easterly wave and floods are prevalent in late summer. All-island daytime land temperatures exceed 38 °C in October and are ~4 °C above sea temperatures during summer. Analysis of thermally induced diurnal convection and circulation revealed inflow during the afternoon recirculated from the southeastern mountains and the warm Mozambique Channel. Summer rainfall follows latent and sensible heat flux during the first half of the day, and gains a surplus by evening via thunderstorms over the western plains. At the inter-annual time-scale, 2.3 years oscillations in all-island rainfall appear linked with the stratospheric quasi-biennial oscillation and corresponding 80 Dobson Unit ozone fluctuations during flood events. Wet spells at frequencies from 11-27 days derive from locally-formed tropical cyclones and NW-cloud bands. Flood case studies exhibit moisture recycling in the confluence zone between the sub-tropical anticyclone and the lee-side vortex. Hovmoller analysis of daily rainfall reinforces the concept of local generation and pulsing by cross-equatorial (Indian winter) monsoon flow rather than zonal atmospheric waves. Since the surface water budget is critical to agriculture in Madagascar, this study represents a further step to understand its meso-scale summer climate.

  2. First detection of ammonia (NH3) in the Asian summer monsoon upper troposphere

    NASA Astrophysics Data System (ADS)

    Höpfner, Michael; Volkamer, Rainer; Grabowski, Udo; Grutter, Michel; Orphal, Johannes; Stiller, Gabriele; von Clarmann, Thomas; Wetzel, Gerald

    2016-11-01

    Ammonia (NH3) has been detected in the upper troposphere by the analysis of averaged MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) infrared limb-emission spectra. We have found enhanced amounts of NH3 within the region of the Asian summer monsoon at 12-15 km altitude. Three-monthly, 10° longitude × 10° latitude average profiles reaching maximum mixing ratios of around 30 pptv in this altitude range have been retrieved, with a vertical resolution of 3-8 km and estimated errors of about 5 pptv. These observations show that loss processes during transport from the boundary layer to the upper troposphere within the Asian monsoon do not deplete the air entirely of NH3. Thus, ammonia might contribute to the so-called Asian tropopause aerosol layer by the formation of ammonium aerosol particles. On a global scale, outside the monsoon area and during different seasons, we could not detect enhanced values of NH3 above the actual detection limit of about 3-5 pptv. This upper bound helps to constrain global model simulations.

  3. Empirical prediction of Indian summer monsoon rainfall with different lead periods based on global SST anomalies

    NASA Astrophysics Data System (ADS)

    Pai, D. S.; Rajeevan, M.

    2006-02-01

    The main objective of this study was to develop empirical models with different seasonal lead time periods for the long range prediction of seasonal (June to September) Indian summer monsoon rainfall (ISMR). For this purpose, 13 predictors having significant and stable relationships with ISMR were derived by the correlation analysis of global grid point seasonal Sea-Surface Temperature (SST) anomalies and the tendency in the SST anomalies. The time lags of the seasonal SST anomalies were varied from 1 season to 4 years behind the reference monsoon season. The basic SST data set used was the monthly NOAA Extended Reconstructed Global SST (ERSST) data at 2° × 2° spatial grid for the period 1951 2003. The time lags of the 13 predictors derived from various areas of all three tropical ocean basins (Indian, Pacific and Atlantic Oceans) varied from 1 season to 3 years. Based on these inter-correlated predictors, 3 predictor sub sets A, B and C were formed with prediction lead time periods of 0, 1 and 2 seasons, respectively, from the beginning of the monsoon season. The selected principal components (PCs) of these predictor sets were used as the input parameters for the models A, B and C, respectively. The model development period was 1955 1984. The correct model size was derived using all-possible regressions procedure and Mallow’s “Cp” statistics.

  4. Southern Bay of Bengal currents and salinity intrusions during the northeast monsoon

    NASA Astrophysics Data System (ADS)

    Wijesekera, H. W.; Jensen, T. G.; Jarosz, E.; Teague, W. J.; Metzger, E. J.; Wang, D. W.; Jinadasa, S. U. P.; Arulananthan, K.; Centurioni, L. R.; Fernando, H. J. S.

    2015-10-01

    Shipboard velocity and hydrographic profiles collected in December 2013 along with drifter observations, satellite altimetry, global ocean nowcast/forecast products, and coupled model simulations were used to examine the circulation in the southern Bay of Bengal as part of ongoing international research efforts in the region. The observations captured the southward flowing East India Coastal Current (EICC) off southeast India and east of Sri Lanka. The EICC was approximately 100 km wide, with speeds exceeding 1 m s-1 in the upper 75 m. East of the EICC, a subsurface-intensified 300 km-wide, northward current was observed, with maximum speeds as high as 1 m s-1 between 50 m and 75 m. The EICC moved low-salinity water out of the bay and the subsurface northward flow carried high-salinity water into the bay during typical northeast monsoon conditions during a time period when the central equatorial Indian Ocean was experiencing a westerly wind burst related to the Madden-Julian Oscillation (MJO) event. While the northward subsurface high-salinity flow has previously been observed during the southwest monsoon, it was observed during the northeast monsoon. The observations are consistent with northward high-salinity subsurface flow in numerical model solutions. The analysis suggests that direct forcing along the equator may play a significant role for high-salinity intrusions east of Sri Lanka.

  5. Solar forcing of the Indian summer monsoon variability during the Ållerød period.

    PubMed

    Gupta, Anil K; Mohan, Kuppusamy; Das, Moumita; Singh, Raj K

    2013-09-25

    Rapid climatic shifts across the last glacial to Holocene transition are pervasive feature of the North Atlantic as well as low latitude proxy archives. Our decadal to centennial scale record of summer monsoon proxy Globigerina bulloides from rapidly accumulating sediments from Hole 723A, Arabian Sea shows two distinct intervals of weak summer monsoon wind coinciding with cold periods within Ållerød inerstadial of the North Atlantic named here as IACP-A1 and IACP-A2 and dated (within dating uncertainties) at 13.5 and 13.3 calibrated kilo years before the present (cal kyr BP), respectively. Spectral analysis of the Globigerina bulloides time series for the segment 13.6-13.1 kyr (Ållerød period) reveals a strong solar 208-year cycle also known as de Vries or Suess cycle, suggesting that the centennial scale variability in Indian summer monsoon winds during the Ållerød inerstadial was driven by changes in the solar irradiance through stratospheric-tropospheric interactions.

  6. The Thermocline Layer and Chlorophyll-a Concentration Variability during Southeast Monsoon in the Banda Sea

    NASA Astrophysics Data System (ADS)

    Pusparini, Nikita; Prasetyo, Budi; Ambariyanto; Widowati, Ita

    2017-02-01

    Thermocline layer and chlorophyll-a concentration can be used to investigate the upwelling region. This investigation is focused in the Banda Sea because the upwelling event in this area is quite large and has a longer upwelling duration than other waters in Indonesia. In addition, Banda Sea is also influenced by climatic factors such as monsoon. The aim of this research is to determine the validation of secondary data (from satellite imagery data and model) and in situ observation data (from research cruise) and to determine the variability of thermocline layer and chlorophyll-a concentration during Southeast Monsoon in the Banda Sea. The data used in this study were chlorophyll-a concentration, seawater vertical temperature at depths 0-400 meters, and sea surface temperature from remote sensing and in situ data. Spatial and temporal analysis of all parameters was conducted by quantitative descriptive method. The results showed that the variability of thermocline layer and the chlorophyll-a distribution were strongly related to seasonal pattern. In most cases, the estimates of thermocline layer and chlorophyll-a concentration using remote sensing algorithm were higher than in situ measured values. The greatest variability occurred in the eastern Banda Sea during the Southeast Monsoon with shallower thermocline layer, more abundance of chlorophyll-a concentration, and lower sea surface temperature.

  7. Winter monsoon variability and its impact on aerosol concentrations in East Asia.

    PubMed

    Jeong, Jaein I; Park, Rokjin J

    2017-02-01

    We investigate the relationship between winter aerosol concentrations over East Asia and variability in the East Asian winter monsoon (EAWM) using GEOS-Chem 3-D global chemical transport model simulations and ground-based aerosol concentration data. We find that both observed and modeled surface aerosol concentrations have strong relationships with the intensity of the EAWM over northern (30-50°N, 100-140°E) and southern (20-30°N, 100-140°E) East Asia. In strong winter monsoon years, compared to weak winter monsoon years, lower and higher surface PM2.5 concentrations by up to 25% are shown over northern and southern East Asia, respectively. Analysis of the simulated results indicates that the southward transport of aerosols is a key process controlling changes in aerosol concentrations over East Asia associated with the EAWM. Variability in the EAWM is found to play a major role in interannual variations in aerosol concentrations; consequently, changes in the EAWM will be important for understanding future changes in wintertime air quality over East Asia.

  8. Solar forcing of the Indian summer monsoon variability during the Ållerød period

    PubMed Central

    Gupta, Anil K.; Mohan, Kuppusamy; Das, Moumita; Singh, Raj K.

    2013-01-01

    Rapid climatic shifts across the last glacial to Holocene transition are pervasive feature of the North Atlantic as well as low latitude proxy archives. Our decadal to centennial scale record of summer monsoon proxy Globigerina bulloides from rapidly accumulating sediments from Hole 723A, Arabian Sea shows two distinct intervals of weak summer monsoon wind coinciding with cold periods within Ållerød inerstadial of the North Atlantic named here as IACP-A1 and IACP-A2 and dated (within dating uncertainties) at 13.5 and 13.3 calibrated kilo years before the present (cal kyr BP), respectively. Spectral analysis of the Globigerina bulloides time series for the segment 13.6–13.1 kyr (Ållerød period) reveals a strong solar 208-year cycle also known as de Vries or Suess cycle, suggesting that the centennial scale variability in Indian summer monsoon winds during the Ållerød inerstadial was driven by changes in the solar irradiance through stratospheric-tropospheric interactions. PMID:24067487

  9. Intraseasonal Variability of Summer Monsoon Rainfall and Droughts over Central India

    NASA Astrophysics Data System (ADS)

    Shrivastava, Sourabh; Kar, Sarat C.; Sharma, Anu Rani

    2017-02-01

    Rainfall over Madhya Pradesh (MP) in central India has large intra-seasonal variability causing droughts and floods in many years. In this study, rainfall variability in daily and monthly scale over central India has been examined using observed data. Consistency among various datasets such as rainfall, surface temperature, soil moisture and evapotranspiration has been examined. These parameters are from various different sources and critical for drought monitoring and prediction. It is found that during weak phases of monsoon, central India receives deficit rainfall with weaker monsoon circulation. This phase is characterized by an anticyclonic circulation at 850 hPa centered on MP. The EOF analysis of daily rainfall suggests that the two leading modes explain about 23-24% of rainfall variability in intraseasonal timescale. These two modes represent drought/flood conditions over MP. Relationship of weak phases of rainfall over central India with real-time multivariate (RMM) indices of Madden Julian Oscillation (MJO) has been examined. It is found that RMM-6, RMM-7, RMM-1 and RMM-2 describe the weak monsoon conditions over central India. However, frequency of drought occurrence over MP is more during RMM-7 phase. Surface temperature increases by about 0.5°-1° during weak phases of rainfall over this region. Soil moisture and evapotranspiration gradually reduce when rainfall reduces over the study region. Soil moisture and evapotranspiration anomalies have positive pattern during good rainfall events over central India and gradually reduce and become negative anomalies during weak phases.

  10. Heterogeneity in pre-monsoon aerosol characteristics over the Indo-Gangetic Basin

    NASA Astrophysics Data System (ADS)

    Tiwari, S.; Srivastava, A. K.; Singh, A. K.

    2013-10-01

    Heterogeneity in aerosol characteristics was studied at five different locations over the Indo-Gangetic Basin (IGB) region during the pre-monsoon period (April-June 2011) using concurrent measurements from sun/sky radiometer, which is hypothesized to affect the Indian monsoon circulation and also the global climate system. Based on the measured aerosol products, distribution of aerosols and the associated optical properties were examined over the entire region. The pre-monsoon mean aerosol optical depth (AOD) was found to be maximum at Lahore (0.78) and Kanpur (0.68); however, a minimum AOD (∼0.6) was observed at Karachi, Jaipur and Gandhi College, with relatively high variability at Karachi and low at Gandhi College. On the other hand, a significant gradient in Angstrom exponent (AE) from Karachi (0.30) in the west to Gandhi College (0.98) in the east IGB region suggests relative dominance of coarse particles over the western part and fine particles at the eastern part of the IGB. Results are confirmed with the aerosol size distribution and the air mass back-trajectory analysis at all the stations. The corresponding pre-monsoon mean single scattering albedo (SSA) shows relatively higher value at Karachi (0.94), suggests relative dominance of scattering type particles. On the other hand, lower SSA, ranging from 0.85 to 0.92, was observed at the other stations, with the lowest value at Gandhi College (0.85), which suggests absorbing aerosol distributions over the region.

  11. Simulation of the West African Monsoon using the MIT Regional Climate Model

    NASA Astrophysics Data System (ADS)

    Im, Eun-Soon; Gianotti, Rebecca L.; Eltahir, Elfatih A. B.

    2013-04-01

    We test the performance of the MIT Regional Climate Model (MRCM) in simulating the West African Monsoon. MRCM introduces several improvements over Regional Climate Model version 3 (RegCM3) including coupling of Integrated Biosphere Simulator (IBIS) land surface scheme, a new albedo assignment method, a new convective cloud and rainfall auto-conversion scheme, and a modified boundary layer height and cloud scheme. Using MRCM, we carried out a series of experiments implementing two different land surface schemes (IBIS and BATS) and three convection schemes (Grell with the Fritsch-Chappell closure, standard Emanuel, and modified Emanuel that includes the new convective cloud scheme). Our analysis primarily focused on comparing the precipitation characteristics, surface energy balance and large scale circulations against various observations. We document a significant sensitivity of the West African monsoon simulation to the choices of the land surface and convection schemes. In spite of several deficiencies, the simulation with the combination of IBIS and modified Emanuel schemes shows the best performance reflected in a marked improvement of precipitation in terms of spatial distribution and monsoon features. In particular, the coupling of IBIS leads to representations of the surface energy balance and partitioning that are consistent with observations. Therefore, the major components of the surface energy budget (including radiation fluxes) in the IBIS simulations are in better agreement with observation than those from our BATS simulation, or from previous similar studies (e.g Steiner et al., 2009), both qualitatively and quantitatively. The IBIS simulations also reasonably reproduce the dynamical structure of vertically stratified behavior of the atmospheric circulation with three major components: westerly monsoon flow, African Easterly Jet (AEJ), and Tropical Easterly Jet (TEJ). In addition, since the modified Emanuel scheme tends to reduce the precipitation

  12. Interhemispheric Changes in Atlantic Ocean Heat Content and Their Link to Global Monsoons

    NASA Astrophysics Data System (ADS)

    Lopez, H.; Lee, S. K.; Dong, S.; Goni, G. J.

    2015-12-01

    This study tested the hypothesis whether low frequency decadal variability of the South Atlantic meridional heat transport (SAMHT) influences decadal variability of the global monsoons. A multi-century run from a state-of-the-art coupled general circulation model is used as basis for the analysis. Our findings indicate that multi-decadal variability of the South Atlantic Ocean plays a key role in modulating atmospheric circulation via interhemispheric changes in Atlantic Ocean heat content. Weaker SAMHT produces anomalous ocean heat divergence over the South Atlantic resulting in negative ocean heat content anomaly about 15 years later. This, in turn, forces a thermally direct anomalous interhemispheric Hadley circulation in the atmosphere, transporting heat from the northern hemisphere (NH) to the southern hemisphere (SH) and moisture from the SH to the NH, thereby intensify (weaken) summer (winter) monsoon in the NH and winter (summer) monsoon in the SH. Results also show that anomalous atmospheric eddies, both transient and stationary, transport heat northward in both hemispheres producing eddy heat flux convergence (divergence) in the NH (SH) around 15-30°, reinforcing the anomalous Hadley circulation. The effect of eddies on the NH (SH) poleward of 30° is opposite with heat flux divergence (convergence), which must be balanced by sinking (rising) motion, consistent with a poleward (equatorward) displacement of the jet stream and mean storm track. The mechanism described here could easily be interpreted for the case of strong SAMHT, with the reverse influence on the interhemispheric atmospheric circulation and monsoons. Overall, SAMHT decadal variability leads its atmospheric response by about 15 years, suggesting that the South Atlantic is a potential predictor of global climate variability.

  13. Hydrological changes of DOM composition and biodegradability of rivers in temperate monsoon climates

    NASA Astrophysics Data System (ADS)

    Shin, Yera; Lee, Eun-Ju; Jeon, Young-Joon; Hur, Jin; Oh, Neung-Hwan

    2016-09-01

    The spatial and hydrological dynamics of dissolved organic matter (DOM) composition and biodegradability were investigated for the five largest rivers in the Republic of Korea (South Korea) during the years 2012-2013 using incubation experiments and spectroscopic measurements, which included parallel factor analysis (PARAFAC). The lower reaches of the five rivers were selected as windows showing the integrated effects of basin biogeochemistry of different land use under Asian monsoon climates, providing an insight on consistency of DOM dynamics across multiple sites which could be difficult to obtain from a study on an individual river. The mean dissolved organic carbon (DOC) concentrations of the five rivers were relatively low, ranging from 1.4 to 3.4 mg L-1, due to the high slope and low percentage of wetland cover in the basin. Terrestrial humic- and fulvic-like components were dominant in all the rivers except for one, where protein-like compounds were up to ∼80%. However, terrestrial components became dominant in all five of the rivers after high precipitation during the summer monsoon season, indicating the strong role of hydrology on riverine DOM compositions for the basins under Asian monsoon climates. Considering that 64% of South Korea is forested, our results suggest that the forests could be a large source of riverine DOM, elevating the DOM loads during monsoon rainfall. Although more DOM was degraded when DOM input increased, regardless of its sources, the percent biodegradability was reduced with increased proportions of terrestrially derived aromatic compounds. The shift in DOM quality towards higher percentages of aromatic terrestrial compounds may alter the balance of the carbon cycle of coastal ecosystems by changing microbial metabolic processes if climate extremes such as heavy storms and typhoons become more frequent due to climate change.

  14. Influence of cosmic-ray variability on the monsoon rainfall and temperature

    NASA Astrophysics Data System (ADS)

    Badruddin; Aslam, O. P. M.

    2015-01-01

    We study the role of galactic cosmic ray (GCR) variability in influencing the rainfall variability in Indian Summer Monsoon Rainfall (ISMR) season. We find that on an average during 'drought' (low ISMR) periods in India, GCR flux is decreasing, and during 'flood' (high ISMR) periods, GCR flux is increasing. The results of our analysis suggest for a possibility that the decreasing GCR flux during the summer monsoon season in India may suppress the rainfall. On the other hand, increasing GCR flux may enhance the rainfall. We suspect that in addition to real environmental conditions, significant levitation/dispersion of low clouds and hence reduced possibility of collision/coalescence to form raindrops suppresses the rainfall during decreasing GCR flux in monsoon season. On the other hand, enhanced collision/coalescence efficiency during increasing GCR flux due to electrical effects may contribute to enhancing the rainfall. Based on the observations, we put forward the idea that, under suitable environmental conditions, changing GCR flux may influence precipitation by suppressing/enhancing it, depending upon the decreasing/increasing nature of GCR flux variability during monsoon season in India, at least. We further note that the rainfall variability is inversely related to the temperature variation during ISMR season. We suggest an explanation, although speculative, how a decreasing/increasing GCR flux can influence the rainfall and the temperature. We speculate that the proposed hypothesis, based on the Indian climate data can be extended to whole tropical and sub-tropical belt, and that it may contribute to global temperature in a significant way. If correct, our hypothesis has important implication for the sun - climate link.

  15. Seasonal Changes of DOC Composition of Rivers in Temperate Monsoon Climates

    NASA Astrophysics Data System (ADS)

    Oh, N. H.; Shin, Y.; Lee, E. J.; Hur, J.

    2014-12-01

    The spatial and seasonal dynamics of dissolved organic carbon (DOC) composition and biodegradability were investigated for the five largest rivers in the Republic of Korea during the years 2012 - 2013 using dark incubation experiments and spectroscopic measurements, including parallel factor analysis (PARAFAC). The DOC concentrations of the rivers in relatively steep and forest-dominated basins were <~2 mg L-1, and remained relatively constant over the seasons. In contrast, those of the rivers influenced by urban and agricultural activities rose up to 5.4 mg L-1, which was decreased to ~2 mg L-1 during the summer monsoon period, indicating that increased precipitation had the effect of dilution. Among the fluorescence components, terrestrial humic-like components were dominant in all the rivers except for one, where tyrosine- or tryptophan-like compounds were the major component. However, terrestrial humic-like components became dominant in all five of the rivers after high precipitation which occurred during the monsoon season, during which ~76% of the annual precipitation was received. Considering that 64% of South Korea is forested, our results suggest that the forests could be a large source of riverine DOC, elevating the DOC loads during monsoon rainfall. Although more DOC could be degraded when DOC input increased, regardless of its sources, the percent biodegradability was reduced with increased proportions of terrestrially derived and aromatic compounds. These results suggest that the relatively stable and terrestrial humic-like compounds released during the monsoon rainfall could reduce the potential of microbial respiration of riverine DOC and evasion of river CO2 to the atmosphere, despite of the increase in the DOC load.

  16. Meridional Propagation of the MJO/ISO and Asian Monsoon Variability

    NASA Technical Reports Server (NTRS)

    Wu, Man Li C.; Schubert, Siegfried; Suarez, Max; Pegion, Phil; Waliser, D.

    2003-01-01

    In this study we examine the links between tropical heating, the Madden Julian Oscillation (MJO)/Intraseasonal Oscillation (ISO), and the Asian monsoon. We are particularly interested in isolating the nature of the poleward propagation of the ISO/MJO in the monsoon region. We examine both observations and idealized "MJO heating" experiments employing the NASA Seasonal-Interannual Prediction Project (NSIPP) atmospheric general circulation model (AGCM). In the idealized 10-member ensemble simulations, the model is forced by climatological SST and an idealized eastward propagating heating profile that is meant to mimic the canonical heating associated with the MJO in the Indian Ocean and western Pacific. In order to understand the impact of SST on the off equatorial convection (or Rossby-wave response), a second set of 10-member ensemble simulations is carried out with the climatological SSTs shifted in time by 6-months. The observational analysis highlights the strong link between the Indian summer monsoon and the tropical ISO/MJO activity and heating. This includes the well-known meridional propagation that affects the summer monsoons of both hemispheres. The AGCM experiments with the idealized eastward propagating MJO-like heating reproduce the observed meridional propagation including the observed seasonal differences. The impact of the SSTs are to enhance the magnitude of the propagation into the summer hemispheres. The results suggest that the winter/summer differences associated with the MJO/ISO are auxiliary features that depend on the MJO's environment (basic state and boundary conditions) and are not the result of fundamental differences in the MJO itself.

  17. Post-Pliocene establishment of the present monsoonal climate in SW China: evidence from the late Pliocene Longmen megaflora

    NASA Astrophysics Data System (ADS)

    Su, T.; Jacques, F. M. B.; Spicer, R. A.; Liu, Y.-S.; Huang, Y.-J.; Xing, Y.-W.; Zhou, Z.-K.

    2013-08-01

    The paleoclimate of the late Pliocene Longmen flora from Yongping County located at the southeastern boundary of the Qinghai-Tibet Plateau was reconstructed using two leaf-physiognomy-based methods, i.e., leaf margin analysis (LMA) and Climate Leaf Analysis Multivariate Program (CLAMP), to understand the paleoclimate condition and geographical pattern of monsoonal climate in southwestern China during the late Pliocene. The mean annual temperatures (MATs) estimated by LMA and CLAMP are 17.4 ± 3.3 °C and 17.4 ± 1.3 °C, respectively, compared with 15.9 °C at present. Meanwhile, the growing season precipitation (GSP) estimated by CLAMP is 1735.5 ± 217.7 mm in the Longmen flora, compared with 986.9 mm nowadays. The calculated monsoon intensity index (MSI) of the Longmen flora is significantly lower than that of today. These results appear consistent with previous studies on the late Pliocene floras in western Yunnan based on the coexistence approach (CA), and further suggest that there was a slightly warmer and much wetter climate during the late Pliocene than the present climate in western Yunnan. We conclude that the significant change of the monsoonal climate might have been resulted from the continuous uplift of mountains in western Yunnan, as well as the intensification of the eastern Asian winter monsoon, both occurring concurrently in the post-Pliocene period.

  18. Post-Pliocene establishment of the present monsoonal climate in SW China: evidence from the late Pliocene Longmen megaflora

    NASA Astrophysics Data System (ADS)

    Su, T.; Jacques, F. M. B.; Spicer, R. A.; Liu, Y.-S.; Huang, Y.-J.; Xing, Y.-W.; Zhou, Z.-K.

    2013-04-01

    The paleoclimate of the late Pliocene Longmen flora from Yongping County located at the southeastern boundary of the Qinghai-Tibet Plateau was reconstructed using two leaf physiognomy based methods, i.e. Leaf Margin Analysis (LMA) and Climate Leaf Analysis Multivariate Program (CLAMP), to understand the paleoclimate condition and geographical pattern of monsoonal climate in southwestern China during the late Pliocene. The mean annual temperatures (MATs) estimated by LMA and CLAMP are 17.4 ± 3.3 °C and 17.4 ± 1.3 °C, respectively, compared with 15.9 °C at present. Meanwhile, the growing season precipitation (GSP) estimated by CLAMP is 1735.5 ± 217.7 mm in the Longmen flora, compared with 986.9 mm nowadays. The calculated monsoon index (MSI) of the Longmen flora is significantly lower than that of today. These results appear consistent with previous studies based on the coexistence approach (CA), and further suggest that there was a slightly warmer and much wetter climate during the late Pliocene than the present climate in western Yunnan. We conclude that the significant change of the monsoonal climate might have been resulted from the continuous uplift of mountains in western Yunnan, as well as the intensification of eastern Asian winter monsoon, both occurring concurrently in the post-Pliocene period.

  19. A Multidisciplinary Approach to Sustainable Management of Watershed Resources

    EPA Science Inventory

    The lack of integration in the study and management of water resource problems suggests the need for a multidisciplinary approach. As practiced in the Shepherd Creek stormwater management study (Cincinnati OH), we envision a multidisciplinary approach involving economic incentive...

  20. Stronger Solar-ENSO connections than ENSO-rainfall connections in the Indian Monsoon

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, S.; Narasimha, R.

    2008-12-01

    Evidence presented in this paper shows that connections of ENSO with solar activity parameters are statistically stronger than those between ENSO and Indian summer monsoon rainfall. The global wavelet cross spectrum between solar irradiance and (a) monsoon rainfall and (b) the global ENSO index, show significant power around the dominant period of the 11 year solar cycle, passing the chi-squared test of significance proposed by Torrence and Compo (1998) at levels exceeding 95% and 97.5% respectively. In particular, the confidence level for the solar irradiance--ENSO index is as high as 97.5%. On the other hand the global wavelet cross power spectrum between the ENSO index and the all India summer monsoon rainfall (AISMR) shows a peak in the 3-4 year period range at significance levels of only 70%. The computed cross- spectrum shows that the average rainfall is higher and the average ENSO index lower during a test period (1933-1964) of greater solar activity; the z-test confidence levels for the solar irradiance-sunspot-AISMR- ENSO connections exceed 95%. Even over the slightly longer period of 1850-1998 over which the AISMR has been reconstructed, statistical analysis reveals significant influence by sunspots and solar irradiance, particularly over the two test-periods of 1878-1913 and 1933-1964, respectively representing three complete cycles of lowest and highest solar activity in the 148 y record. An increase in solar activity is accompanied by a decrease in ENSO and an increase in rainfall at the 8-16 y band. The link between ENSO and solar activity (95%) is weaker than the link between solar activity and rainfall (97.5%) but stronger than that between ENSO and rainfall (70%). The effect of Nino 3.4 positive tendencies on the monsoon rainfall is to decrease the rainfall. Both these effects occur in the test periods of lower solar activity. The global cross spectrum for ENSO and solar activity index exhibits peaks around the 11 y period at confidence levels of

  1. Sustainability Within the Great Monsoon River Basins

    NASA Astrophysics Data System (ADS)

    Webster, P. J.

    2014-12-01

    For over five millenia, the great monsoon river basins of the Ganges, Brahmaputra and Indus have provided for great and flourishing agrarian civilizations. However, rapid population growth and urbanization have placed stress on the rural sector causing the use of land that is more prone for flood and drought. In addition, increased population and farming have stressed the availability of fresh water both from rivers and aquifers. Additionally, rapid urbanization has severely reduced water quality within the great rivers. Added to these problems is delta subsidence from water withdrawal that, at the moment far surpasses sea level rise from both natural and anthropogenic effects. Finally, there appear to be great plans for river diversion that may reduce fresh water inflow into the Brahmaputra delta. All of these factors fall against a background of climate change, both anthropogenic and natural, of which there is great uncertainty. We an attempt a frank assessment assessment of the sustainability of society in the great basins and make some suggestions of factors that require attention in the short term.

  2. Improving GEFS Weather Forecasts for Indian Monsoon with Statistical Downscaling

    NASA Astrophysics Data System (ADS)

    Agrawal, Ankita; Salvi, Kaustubh; Ghosh, Subimal

    2014-05-01

    Weather forecast has always been a challenging research problem, yet of a paramount importance as it serves the role of 'key input' in formulating modus operandi for immediate future. Short range rainfall forecasts influence a wide range of entities, right from agricultural industry to a common man. Accurate forecasts actually help in minimizing the possible damage by implementing pre-decided plan of action and hence it is necessary to gauge the quality of forecasts which might vary with the complexity of weather state and regional parameters. Indian Summer Monsoon Rainfall (ISMR) is one such perfect arena to check the quality of weather forecast not only because of the level of intricacy in spatial and temporal patterns associated with it, but also the amount of damage it can cause (because of poor forecasts) to the Indian economy by affecting agriculture Industry. The present study is undertaken with the rationales of assessing, the ability of Global Ensemble Forecast System (GEFS) in predicting ISMR over central India and the skill of statistical downscaling technique in adding value to the predictions by taking them closer to evidentiary target dataset. GEFS is a global numerical weather prediction system providing the forecast results of different climate variables at a fine resolution (0.5 degree and 1 degree). GEFS shows good skills in predicting different climatic variables but fails miserably over rainfall predictions for Indian summer monsoon rainfall, which is evident from a very low to negative correlation values between predicted and observed rainfall. Towards the fulfilment of second rationale, the statistical relationship is established between the reasonably well predicted climate variables (GEFS) and observed rainfall. The GEFS predictors are treated with multicollinearity and dimensionality reduction techniques, such as principal component analysis (PCA) and least absolute shrinkage and selection operator (LASSO). Statistical relationship is

  3. Understanding and prediction of Monsoon Intraseasonal Oscillation (Invited)

    NASA Astrophysics Data System (ADS)

    Wang, B.

    2013-12-01

    Compared with the Madden-Julian Oscillation (MJO), which prevails in boreal winter, the boreal summer intraseasonal oscillation (BSISO) has a more complex propagation pattern and spatial- temporal evolution, with prominent northward propagation and a shift of the variability center from the equatorial region to the Asian-western North Pacific and North American monsoon regions. Understanding the origin and perpetuation of BSISO has eluded scientists for decades. Improved understanding of the physical mechanisms is a prerequisite for improvement of BSISO prediction. An account of essential aspects of BSISO is presented, including (a) what sustains it or why a new rainy phase is initiated in the western equatorial Indian Ocean, (b) How a titled BSISO rain band is formed, (c) why its rain bands move northeastward in the Asian-Pacific monsoon regions, (d) how its interaction with mixed layer-ocean can play an important role in its dynamics, and (e) how it interacts with mid-latitude wave trains. Practical useful BSISO indices are proposed for monitoring and prediction purpose based on multivariate empirical orthogonal function (MV-EOF) analysis of daily anomalies of outgoing longwave radiation and zonal wind at 850 hPa in the region 10oS-40oN, 40o-160oE, for the extended boreal summer (May-October) season over the 30-year period 1981-2010. The prediction skill and predictability of the BSISO are also examined in terms of predictable modes identified form observation and multi-model ensemble (MME) hindcasts obtained from ten coupled models participated in the IntraSeasonal Variability Hindcast Experiment (ISVHE) project. It is noted that the first two MV-EOF modes are predictable using the coupled models and the bivariate temporal correlation coefficient skill for the two modes reaches 0.5 at 22-day forecast lead for the best model but at 5-day for the worst model. As a phenomenon bridging synoptic weather and seasonal variability, BSISO predictability is strongly

  4. Formal and heuristic system decomposition methods in multidisciplinary synthesis

    NASA Astrophysics Data System (ADS)

    Bloebaum, Christina Lynne

    The multidisciplinary interactions which exist in large scale engineering design problems provide a unique set of difficulties. These difficulties are associated primarily with unwieldy numbers of design variables and constraints, and with the interdependencies of the discipline analysis modules. Such obstacles require design techniques which account for the inherent disciplinary couplings in the analyses and optimizations. The objective of this work is to develop an efficient holistic design synthesis methodology that takes advantage of the synergistic nature of integrated design. Although the design process encompasses several stages in which optimization methods could be applied, the present study addresses the applications of optimization in the preliminary design stage, in which the most capability for positive change exists. A primary concern in this stage involves implementation of an accurate and efficient mathematical representation of large engineering systems. Without such a representation, meaningful design synthesis is impossible. Multilevel decomposition methods provide a systematic approach for decoupling the large complex systems found in multidisciplinary design problems into smaller, more manageable subsystems. These methods account for the couplings between the intrinsically linked disciplinary analysis modules on the basis of a linear sensitivity analysis. In a majority of such efforts, the decomposition is governed either by an obvious hierarchy in the system or on the basis of discipline.

  5. Monsoon failure enhances drought in southwestern North America

    NASA Astrophysics Data System (ADS)

    Griffin, D.; Woodhouse, C. A.; Meko, D. M.; Stahle, D. W.

    2012-12-01

    The North American monsoon has emerged as a research frontier for paleoclimatology. Precisely dated tree-ring latewood (summer growth) offers unparalleled promise for studying interannual- to decadal-scale monsoon variability over past centuries. From the new network of latewood chronologies in the southwestern U.S., we present a high-quality, 470-year long reconstruction of June-August (monsoon) precipitation for the Arizona-Sonora sub-region of the North American monsoon. For comparison, we developed a companion reconstruction of October-April (cool-season) precipitation from chronologies of earlywood (spring growth). Foremost, these reconstructions demonstrate that many of the well-known southwestern droughts were not just cool-season events, but were also characterized by concurrent failure of the summer monsoon. The early 21st century drought, the late 19th century drought, the 17th century Puebloan drought, and even the 16th century megadrought each contain notable runs of consecutive years with below average monsoon rainfall. The reconstructions also reveal that the interannual relationship between winter and summer precipitation has been unstable through time and that the tendency for dry (wet) winters to be followed by wet [dry] summers was anomalously high during the mid-late 20th century. Cool-season and monsoon moisture variability in this region can be linked to patterns of ocean-atmosphere circulation. However, our understanding of the climate dynamics that would facilitate persistence of dual-season drought and transience in the winter-summer precipitation relationship is far from complete.

  6. Asian Monsoon Variability from the Monsoon Asia Drought Atlas (MADA) and Links to Indo-Pacific Climate

    NASA Astrophysics Data System (ADS)

    Ummenhofer, Caroline; D'Arrigo, Rosanne; Anchukaitis, Kevin; Hernandez, Manuel; Buckley, Brendan; Cook, Edward

    2014-05-01

    Drought patterns across monsoon and temperate Asia over the period 1877-2005 are linked to Indo-Pacific climate variability associated with the El Niño-Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). Using the Monsoon Asia Drought Atlas (MADA) composed of a high-resolution network of hydroclimatically sensitive tree-ring records with a focus on the June-August months, spatial drought patterns during El Niño and IOD events are assessed as to their agreement with an instrumental drought index and consistency in the drought response amongst ENSO/IOD events. Spatial characteristics in drought patterns are related to regional climate anomalies over the Indo-Pacific basin, using reanalysis products, including changes in the Asian monsoon systems, zonal Walker circulation, moisture fluxes, and precipitation. A weakening of the monsoon circulation over the Indian subcontinent and Southeast Asia during El Niño events, along with anomalous subsidence over monsoon Asia and reduced moisture flux, is reflected in anomalous drought conditions over India, Southeast Asia and Indonesia. When an IOD event co-occurs with an El Niño, severe drought conditions identified in the MADA for Southeast Asia, Indonesia, eastern China and central Asia are associated with a weakened South Asian monsoon, reduced moisture flux over China, and anomalous divergent flow and subsidence over Indonesia. Variations in the strength of the South Asian monsoon can also be linked to the Strange Parallels Drought (1756-1768) affecting much of Southeast Asia and the Indian subcontinent in the mid-18th Century. Large-scale climate anomalies across the wider region during years with an anomalously strengthened/weakened South Asian monsoon are discussed with implications for severe droughts prior to the instrumental period. Insights into the relative influences of Pacific and Indian Ocean variability for Asian monsoon climate on interannual to decadal and longer timescales, as recorded in the

  7. Holocene Climatic Variability in the Indian Monsoon Domain

    NASA Astrophysics Data System (ADS)

    Mishra, Praveen Kumar; Anoop, Ambili; Menzel, Philip; Gaye, Birgit; Basavaiah, Nathani; Jehangir, Arshid; Prasad, Sushma

    2013-04-01

    The available data on Holocene climate variability from Asia indicates spatio-temporal changes in the precipitation over this vast region. Detailed information on the timing, duration, regionality, and causes of these fluctuations is not well understood, especially over the Indian subcontinent. My work focuses on long core sediments from lake Tso Moriri (78°14'-78°25'N and 32°40'-33°02'E; altitude: 4500 m) situated in climatically sensitive zone of NW Himalayas affected by both mid-latitude westerlies and Indian summer monsoon. Two cores ca.7 m were retrieved from the lake at different water depths (ca. 40m and 105m) in July 2011. Investigations reveal marked changes in grain size, lamination quality, mineralogy, organic and carbonate content suggesting changes in lake level, direction of inflow, and biological productivity that in turn are influenced by regional climate. As the lake lies in a tectonically active region, I have also undertaken detailed geomorphometric (knick-point, Hack index), and drainage pattern analysis of the major inflowing streams to decipher the active tectonics in the region. Sharp changes in river course and slope gradient indicates the presence of an active N-S trending fault in western flank of the lake. The data from lake Tso Moriri will be compared with other high-resolution records from lake Lonar and stalagmites in NE India to reconstruct the forcing mechanism of Holocene climatic variability.

  8. The Joint Aerosol-Monsoon Experiment (JAMEX): A Core Element for the Asian Monsoon Year (2008-2009)

    NASA Technical Reports Server (NTRS)

    Lau, William K.M.

    2007-01-01

    The objective of the Joint Aerosol-Monsoon Experiment (JAMEX) is to unravel the physical mechanisms and multi-scale interactions associated with aerosol-monsoon water cycle in the Asian Indo-Pacific region towards improved prediction of rainfall in land regions of the Asian monsoon. JAMEX will be planned as a five-year (2007-201 1) multi-national aerosol-monsoon research project, aimed at promoting collaboration, partnership and alignment of ongoing and planned national and international programs. Two coordinated special observing periods (SOP), covering the pre-monsoon (April-May) and the monsoon (June-August) periods is tentatively targeted for 2008 and 2009. The major work on validation and reference site coordination will take place in 2007 through the spring of 2008. A major science workshop is planned after SOP-I1 in 2010. Modeling and satellite data utilization studies will continue throughout the entire period to help in design of the observation arrays and measurement platforms for SOPS. The tentative time schedule, including milestones and research activities is shown in Fig. 1. One of the unique aspects of JAMEX is that it stems from grass-root scientific and societal imperatives, and it bridges a gap in existing national and international research programs. Currently we have identified 10 major national and international projects/programs separately for aerosols and monsoon research planned in the next five years in China, India, Japan, Italy, and the US, that could be potential contributors or partners with JAMEX. These include the Asian-Indo- Pacific Ocean (AIPO) Project and Aerosol Research Project from China, Monsoon Asian Hydro- Atmospheric Science Research and predication Initiative (MAHASRI) from Japan, Continental Tropical Convergence Zone (CTCZ) and Severe Thunderstorm: Observations and Regional Modeling (STORM) from India, Share-Asia from Italy, Atmospheric Brown Cloud (ABC), Pacific Aerosol-Cloud-Dust Experiment (PACDEX), East Asia Study of

  9. The Joint Aerosol-Monsoon Experiment (JAMEX): A Core Element for the Asian Monsoon Year (2008-2009)

    NASA Technical Reports Server (NTRS)

    Lau, WIlliam K. M.

    2007-01-01

    The objective of the Joint Aerosol-Monsoon Experiment (JAMEX) is to unravel the physical mechanisms and multi-scale interactions associated with aerosol-monsoon water cycle in the Asian Indo-Paczj?c region towards improved prediction of rainfall in land regions of the Asian monsoon. JAMEX will be planned as a five-year (2007-201 1) multi-national aerosol-monsoon research project, aimed at promoting collaboration, partnership and alignment of ongoing and planned national and international programs. Two coordinated special observing periods (SOP), covering the pre-monsoon (April-May) and the monsoon (June-August) periods is tentatively targeted for 2008 and 2009. The major work on validation and reference site coordination will take place in 2007 through the spring of 2008. A major science workshop is planned after SOP-I1 in 2010. Modeling and satellite data utilization studies will continue throughout the entire period to help in design of the observation arrays and measurement platforms for SOPS. The tentative time schedule, including milestones and research activities is shown in Fig. 1. One of the unique aspects of JAMEX is that it stems from grass-root scientific and societal imperatives, and it bridges a gap in existing national and international research programs. Currently we have identified 10 major national and international projects/programs separately for aerosols and monsoon research planned in the next five years in China, India, Japan, Italy, and the US, that could be potential contributors or partners with JAMEX. These include the Asian-Indo- Pacific Ocean (AIPO) Project and Aerosol Research Project from China, Monsoon Asian Hydro- Atmospheric Science Research and predication Initiative (MAHASRI) from Japan, Continental Tropical Convergence Zone (CTCZ) and Severe Thunderstorm: Observations and Regional Modeling (STORM) from India, Share-Asia from Italy, Atmospheric Brown Cloud (ABC), Pacific Aerosol-Cloud-Dust Experiment (PACDEX), East Asia Study of

  10. Multidisciplinary design optimization using genetic algorithms

    NASA Technical Reports Server (NTRS)

    Unal, Resit

    1994-01-01

    Multidisciplinary design optimization (MDO) is an important step in the conceptual design and evaluation of launch vehicles since it can have a significant impact on performance and life cycle cost. The objective is to search the system design space to determine values of design variables that optimize the performance characteristic subject to system constraints. Gradient-based optimization routines have been used extensively for aerospace design optimization. However, one limitation of gradient based optimizers is their need for gradient information. Therefore, design problems which include discrete variables can not be studied. Such problems are common in launch vehicle design. For example, the number of engines and material choices must be integer values or assume only a few discrete values. In this study, genetic algorithms are investigated as an approach to MDO problems involving discrete variables and discontinuous domains. Optimization by genetic algorithms (GA) uses a search procedure which is fundamentally different from those gradient based methods. Genetic algorithms seek to find good solutions in an efficient and timely manner rather than finding the best solution. GA are designed to mimic evolutionary selection. A population of candidate designs is evaluated at each iteration, and each individual's probability of reproduction (existence in the next generation) depends on its fitness value (related to the value of the objective function). Progress toward the optimum is achieved by the crossover and mutation operations. GA is attractive since it uses only objective function values in the search process, so gradient calculations are avoided. Hence, GA are able to deal with discrete variables. Studies report success in the use of GA for aircraft design optimization studies, trajectory analysis, space structure design and control systems design. In these studies reliable convergence was achieved, but the number of function evaluations was large compared

  11. Multi-Disciplinary Design Optimization Using WAVE

    NASA Technical Reports Server (NTRS)

    Irwin, Keith

    2000-01-01

    The current preliminary design tools lack the product performance, quality and cost prediction fidelity required to design Six Sigma products. They are also frequently incompatible with the tools used in detailed design, leading to a great deal of rework and lost or discarded data in the transition from preliminary to detailed design. Thus, enhanced preliminary design tools are needed in order to produce adequate financial returns to the business. To achieve this goal, GEAE has focused on building the preliminary design system around the same geometric 3D solid model that will be used in detailed design. With this approach, the preliminary designer will no longer convert a flowpath sketch into an engine cross section but rather, automatically create 3D solid geometry for structural integrity, life, weight, cost, complexity, producibility, and maintainability assessments. Likewise, both the preliminary design and the detailed design can benefit from the use of the same preliminary part sizing routines. The design analysis tools will also be integrated with the 3D solid model to eliminate manual transfer of data between programs. GEAE has aggressively pursued the computerized control of engineering knowledge for many years. Through its study and validation of 3D CAD programs and processes, GEAE concluded that total system control was not feasible at that time. Prior CAD tools focused exclusively on detail part geometry and Knowledge Based Engineering systems concentrated on rules input and data output. A system was needed to bridge the gap between the two to capture the total system. With the introduction of WAVE Engineering from UGS, the possibilities of an engineering system control device began to formulate. GEAE decided to investigate the new WAVE functionality to accomplish this task. NASA joined GEAE in funding this validation project through Task Order No. 1. With the validation project complete, the second phase under Task Order No. 2 was established to

  12. Development of a Multi-Disciplinary Aerothermostructural Model Applicable to Hypersonic Flight

    NASA Technical Reports Server (NTRS)

    Kostyk, Chris; Risch, Tim

    2013-01-01

    The harsh and complex hypersonic flight environment has driven design and analysis improvements for many years. One of the defining characteristics of hypersonic flight is the coupled, multi-disciplinary nature of the dominant physics. In an effect to examine some of the multi-disciplinary problems associated with hypersonic flight engineers at the NASA Dryden Flight Research Center developed a non-linear 6 degrees-of-freedom, full vehicle simulation that includes the necessary model capabilities: aerothermal heating, ablation, and thermal stress solutions. Development of the tool and results for some investigations will be presented. Requirements and improvements for future work will also be reviewed. The results of the work emphasize the need for a coupled, multi-disciplinary analysis to provide accurate

  13. Requirements for multidisciplinary teamwork in psychiatric rehabilitation.

    PubMed

    Liberman, R P; Hilty, D M; Drake, R E; Tsang, H W

    2001-10-01

    Psychiatric rehabilitation by its very nature is multidisciplinary because of the many competencies required for its implementation. In promoting optimal levels of recovery from schizophrenia and other disabling mental disorders, teams must combine the expert contributions of professionals and paraprofessionals who can individualize a comprehensive array of evidence-based services with competency, consistency, continuity, coordination, collaboration, and fidelity. The authors describe the properties and functions of the multidisciplinary team and key attributes of effective teams. The importance of teams' involving clients, their relatives, and other supporters in setting personally relevant life goals is emphasized. The authors provide examples of the challenges posed by the need to individualize services and of the ways in which barriers to communication and coordination can be overcome. The roles of the various team members are described, including leadership roles and the unique role of the psychiatrist, in the context of newly emerging, evidence-based treatments for psychiatric rehabilitation.

  14. Multidisciplinary pulmonary embolism response teams and systems

    PubMed Central

    Monteleone, Peter P.; Rosenfield, Kenneth

    2016-01-01

    Pulmonary embolism (PE) is a complex diagnosis that encompasses a wide range of clinical presentations. Often patients who present with PE have complicated medical histories which can make their management challenging. Many novel therapeutic strategies and tools are emerging to improve the care and outcomes of patients with PE. Pulmonary embolism response teams (PERTs) are developing at multiple centers to improve the decision making, efficiency and orchestration of these clinical strategies. Concordantly with development of PERT programs is the design and implementation of systems to allow for numerous specialists to convene and discuss complex PE patients in real time. The mechanisms to engage a multidisciplinary approach are proving to be an invaluable resource in the decision making processes and treatment of high risk PE patients. Ultimately, other multi-disciplinary teams may adopt these methods to better address their clinical needs. PMID:28123986

  15. A multidisciplinary approach for improving outcomes.

    PubMed

    Sierchio, Grace P

    2003-01-01

    The healthcare environment has been impacted tremendously by higher patient acuity, cost-cutting measures, an increase in litigation, and increased expectations by an educated generation of healthcare consumers. This has led to the need to continually measure, assess, and improve quality. These activities must consider not only patient clinical outcomes, but also customer service ratings and financial outcomes. Quality improvement requires a collaborative approach to succeed, and the need to build a cohesive and effective multidisciplinary team is critical for positive outcomes. Strategies to build a culture of teamwork include incorporating total quality management principles into every level of the organization, seeking participation from every discipline and level of the organization, and recognizing employees for their efforts. Infusion nurses have an excellent opportunity to contribute their expertise to any multidisciplinary team that impacts the outcomes of infusion patients. In addition, team-building and quality improvement may prove to be excellent career moves for infusion nurses looking to further specialize their practice.

  16. Modelling Monsoons: Understanding and Predicting Current and Future Behaviour

    SciTech Connect

    Turner, A; Sperber, K R; Slingo, J M; Meehl, G A; Mechoso, C R; Kimoto, M; Giannini, A

    2008-09-16

    The global monsoon system is so varied and complex that understanding and predicting its diverse behaviour remains a challenge that will occupy modellers for many years to come. Despite the difficult task ahead, an improved monsoon modelling capability has been realized through the inclusion of more detailed physics of the climate system and higher resolution in our numerical models. Perhaps the most crucial improvement to date has been the development of coupled ocean-atmosphere models. From subseasonal to interdecadal timescales, only through the inclusion of air-sea interaction can the proper phasing and teleconnections of convection be attained with respect to sea surface temperature variations. Even then, the response to slow variations in remote forcings (e.g., El Nino-Southern Oscillation) does not result in a robust solution, as there are a host of competing modes of variability that must be represented, including those that appear to be chaotic. Understanding the links between monsoons and land surface processes is not as mature as that explored regarding air-sea interactions. A land surface forcing signal appears to dominate the onset of wet season rainfall over the North American monsoon region, though the relative role of ocean versus land forcing remains a topic of investigation in all the monsoon systems. Also, improved forecasts have been made during periods in which additional sounding observations are available for data assimilation. Thus, there is untapped predictability that can only be attained through the development of a more comprehensive observing system for all monsoon regions. Additionally, improved parameterizations - for example, of convection, cloud, radiation, and boundary layer schemes as well as land surface processes - are essential to realize the full potential of monsoon predictability. Dynamical considerations require ever increased horizontal resolution (probably to 0.5 degree or higher) in order to resolve many monsoon features

  17. Trace gas transport out of the Indian Summer Monsoon

    NASA Astrophysics Data System (ADS)

    Tomsche, Laura; Pozzer, Andrea; Zimmermann, Peter; Parchatka, Uwe; Fischer, Horst

    2016-04-01

    The trace gas transport out of the Indian summer monsoon was investigated during the aircraft campaign OMO (Oxidation Mechanism Observations) with the German research aircraft HALO (High Altitude and Long Range Research Aircraft) in July/August 2015. HALO was based at Paphos/Cyprus and also on Gan/Maledives. Flights took place over the Mediterranean Sea, the Arabian Peninsula and the Arabian Sea. In this work the focus is on the distribution of carbon monoxide (CO) and methane (CH4) in the upper troposphere. They were measured with the laser absorption spectrometer TRISTAR on board of HALO. During the Indian summer monsoon strong convection takes place over India and the Bay of Bengal. In this area the population is high accompanied by many emission sources e.g. wetlands and cultivation of rice. Consequently the boundary layer is polluted containing high concentrations of trace gases like methane and carbon monoxide. Due to vertical transport these polluted air masses are lifted to the upper troposphere. Here they circulate with the so called Asian monsoon anticyclone. In the upper troposphere polluted air masses lead to a change in the chemical composition thus influence the chemical processes. Furthermore the anticyclone spreads the polluted air masses over a larger area. Thus the outflow of the anticyclone in the upper troposphere leads to higher concentrations of trace gases over the Arabian Sea, the Arabian Peninsula and also over the eastern part of North Africa and the eastern part of the Mediterranean Sea. During OMO higher concentrations of methane and carbon monoxide were detected at altitudes between 11km and 15km. The highest measured concentrations of carbon monoxide and methane were observed over Oman. The CO concentration in the outflow of the monsoon exceeds background levels by 10-15ppb. However the enhancement in the concentration is not obviously connected to the monsoon due to the natural variability in the troposphere. The enhancement in the

  18. Numerical Simulation of the Large-Scale North American Monsoon Water Sources

    NASA Technical Reports Server (NTRS)

    Bosilovich, Michael G.; Sud, Yogesh C.; Schubert, Siegfried D.; Walker, Gregory K.

    2002-01-01

    A general circulation model (GCM) that includes water vapor tracer (WVT) diagnostics is used to delineate the dominant sources of water vapor for precipitation during the North American monsoon. A 15-year model simulation carried out with one-degree horizontal resolution and time varying sea surface temperature is able to produce reasonable large-scale features of the monsoon precipitation. Within the core of the Mexican monsoon, continental sources provide much of the water for precipitation. Away from the Mexican monsoon (eastern Mexico and Texas), continental sources generally decrease with monsoon onset. Tropical Atlantic Ocean sources of water gain influence in the southern Great Plains states where the total precipitation decreases during the monsoon onset. Pacific ocean sources do contribute to the monsoon, but tend to be weaker after onset. Evaluating the development of the monsoons, soil water and surface evaporation prior to monsoon onset do not correlate with the eventual monsoon intensity. However, the most intense monsoons do use more local sources of water than the least intense monsoons, but only after the onset. This suggests that precipitation recycling is an important factor in monsoon intensity.

  19. Multidisciplinary intervention in obese adolescents: predictors of dropout

    PubMed Central

    Fidelix, Yara Lucy; de Farias, José Cazuza; Lofrano-Prado, Mara Cristina; Guerra, Ricardo Luís Fernandes; Cardel, Michelle; do Prado, Wagner Luiz

    2015-01-01

    Objective To identify biological and psychosocial factors associated with dropout in a multidisciplinary behavioral intervention in obese adolescents. Methods A total of 183 adolescents (15.4±1.6 years), pubertal (Tanner stage 3 or 4) and obese (34.7±4.0kg/m2), were enrolled in a 12-week behavioral intervention, which included clinical consultations (monthly), nutritional and psychological counseling (once a week), and supervised aerobic training (three times/week). The studied variables were weight, height, body mass index, body composition (skinfold), cardiorespiratory fitness (direct gas analysis), blood lipids and self-reported symptoms of eating disorders (bulimia, anorexia and binge eating), anxiety, depression, body image dissatisfaction and quality of life. Statistical analysis included binary logistic regression and independent t-tests. Results Of the adolescents, 73.7% adhered to the program. The greatest chance for dropout was observed among adolescents older than 15 years (odds ratio of 0.40; 95%CI: 0.15-0.98), with more anorexia symptoms (odds ratio of 0.35; 95%CI: 0.14-0.86) and hypercholesterolemia (odds ratio of 0.40; 95%CI: 0.16-0.91) at baseline. Conclusion Older adolescents, with more symptoms of eating disorders and total cholesterol have less chance to adhere to multidisciplinary treatments. PMID:26466062

  20. East Asian summer monsoon precipitation variability since the last deglaciation

    PubMed Central

    Chen, Fahu; Xu, Qinghai; Chen, Jianhui; Birks, H. John B.; Liu, Jianbao; Zhang, Shengrui; Jin, Liya; An, Chengbang; Telford, Richard J.; Cao, Xianyong; Wang, Zongli; Zhang, Xiaojian; Selvaraj, Kandasamy; Lu, Houyuan; Li, Yuecong; Zheng, Zhuo; Wang, Haipeng; Zhou, Aifeng; Dong, Guanghui; Zhang, Jiawu; Huang, Xiaozhong; Bloemendal, Jan; Rao, Zhiguo

    2015-01-01

    The lack of a precisely-dated, unequivocal climate proxy from northern China, where precipitation variability is traditionally considered as an East Asian summer monsoon (EASM) indicator, impedes our understanding of the behaviour and dynamics of the EASM. Here we present a well-dated, pollen-based, ~20-yr-resolution quantitative precipitation reconstruction (derived using a transfer function) from an alpine lake in North China, which provides for the first time a direct record of EASM evolution since 14.7 ka (ka = thousands of years before present, where the “present” is defined as the year AD 1950). Our record reveals a gradually intensifying monsoon from 14.7–7.0 ka, a maximum monsoon (30% higher precipitation than present) from ~7.8–5.3 ka, and a rapid decline since ~3.3 ka. These insolation-driven EASM trends were punctuated by two millennial-scale weakening events which occurred synchronously to the cold Younger Dryas and at ~9.5–8.5 ka, and by two centennial-scale intervals of enhanced (weakened) monsoon during the Medieval Warm Period (Little Ice Age). Our precipitation reconstruction, consistent with temperature changes but quite different from the prevailing view of EASM evolution, points to strong internal feedback processes driving the EASM, and may aid our understanding of future monsoon behaviour under ongoing anthropogenic climate change. PMID:26084560

  1. Intraseasonal oscillations in East Asian and South Asian monsoons

    NASA Astrophysics Data System (ADS)

    Krishnamurthy, V.

    2016-11-01

    This study has investigated the relation between the East Asian monsoon and the South Asian monsoon at intraseasonal time scale during the boreal summer. Applying a data adaptive method on daily anomalies of precipitation, two leading intraseasonal oscillations (ISOs) were extracted separately in the regions of South Asia, tropical East Asia and subtropical East Asia. The first ISO has a period of about 45 days and propagates northward and eastward over the South Asian and tropical East Asian regions. The second ISO, with a period of about 26 days, propagates northeastward over South Asia and northwestward over tropical East Asia. Although both the ISOs are also present over the subtropical East Asia, the variance is low while no propagation is evident. The circulation patterns associated with the ISOs were found to be consistent with the corresponding precipitation patterns of the ISOs. The two ISOs also reveal consistency with the space-time evolution of diabatic heating, convection, vertical motion, upper-level divergence and moisture transport. The zonal and meridional propagation of the ISOs provide a strong link between the South Asian monsoon and East Asian monsoon regions. The subtropical East Asian region seems to have a weaker link with the other monsoon regions.

  2. Global monsoon precipitation responses to large volcanic eruptions

    PubMed Central

    Liu, Fei; Chai, Jing; Wang, Bin; Liu, Jian; Zhang, Xiao; Wang, Zhiyuan

    2016-01-01

    Climate variation of global monsoon (GM) precipitation involves both internal feedback and external forcing. Here, we focus on strong volcanic forcing since large eruptions are known to be a dominant mechanism in natural climate change. It is not known whether large volcanoes erupted at different latitudes have distinctive effects on the monsoon in the Northern Hemisphere (NH) and the Southern Hemisphere (SH). We address this issue using a 1500-year volcanic sensitivity simulation by the Community Earth System Model version 1.0 (CESM1). Volcanoes are classified into three types based on their meridional aerosol distributions: NH volcanoes, SH volcanoes and equatorial volcanoes. Using the model simulation, we discover that the GM precipitation in one hemisphere is enhanced significantly by the remote volcanic forcing occurring in the other hemisphere. This remote volcanic forcing-induced intensification is mainly through circulation change rather than moisture content change. In addition, the NH volcanic eruptions are more efficient in reducing the NH monsoon precipitation than the equatorial ones, and so do the SH eruptions in weakening the SH monsoon, because the equatorial eruptions, despite reducing moisture content, have weaker effects in weakening the off-equatorial monsoon circulation than the subtropical-extratropical volcanoes do. PMID:27063141

  3. Global monsoon precipitation responses to large volcanic eruptions.

    PubMed

    Liu, Fei; Chai, Jing; Wang, Bin; Liu, Jian; Zhang, Xiao; Wang, Zhiyuan

    2016-04-11

    Climate variation of global monsoon (GM) precipitation involves both internal feedback and external forcing. Here, we focus on strong volcanic forcing since large eruptions are known to be a dominant mechanism in natural climate change. It is not known whether large volcanoes erupted at different latitudes have distinctive effects on the monsoon in the Northern Hemisphere (NH) and the Southern Hemisphere (SH). We address this issue using a 1500-year volcanic sensitivity simulation by the Community Earth System Model version 1.0 (CESM1). Volcanoes are classified into three types based on their meridional aerosol distributions: NH volcanoes, SH volcanoes and equatorial volcanoes. Using the model simulation, we discover that the GM precipitation in one hemisphere is enhanced significantly by the remote volcanic forcing occurring in the other hemisphere. This remote volcanic forcing-induced intensification is mainly through circulation change rather than moisture content change. In addition, the NH volcanic eruptions are more efficient in reducing the NH monsoon precipitation than the equatorial ones, and so do the SH eruptions in weakening the SH monsoon, because the equatorial eruptions, despite reducing moisture content, have weaker effects in weakening the off-equatorial monsoon circulation than the subtropical-extratropical volcanoes do.

  4. Indian monsoon variability on millennial-orbital timescales

    NASA Astrophysics Data System (ADS)

    Kathayat, Gayatri; Cheng, Hai; Sinha, Ashish; Spötl, Christoph; Edwards, R. Lawrence; Zhang, Haiwei; Li, Xianglei; Yi, Liang; Ning, Youfeng; Cai, Yanjun; Lui, Weiguo Lui; Breitenbach, Sebastian F. M.

    2016-04-01

    The Indian summer monsoon (ISM) monsoon is critical to billions of people living in the region. Yet, significant debates remain on primary ISM drivers on millennial-orbital timescales. Here, we use speleothem oxygen isotope (δ18O) data from Bittoo cave, Northern India to reconstruct ISM variability over the past 280,000 years. We find strong coherence between North Indian and Chinese speleothem δ18O records from the East Asian monsoon domain, suggesting that both Asian monsoon subsystems exhibit a coupled response to changes in Northern Hemisphere summer insolation (NHSI) without significant temporal lags, supporting the view that the tropical-subtropical monsoon variability is driven directly by precession-induced changes in NHSI. Comparisons of the North Indian record with both Antarctic ice core and sea-surface temperature records from the southern Indian Ocean over the last glacial period do not suggest a dominant role of Southern Hemisphere climate processes in regulating the ISM variability on millennial-orbital timescales.

  5. East Asian summer monsoon precipitation variability since the last deglaciation.

    PubMed

    Chen, Fahu; Xu, Qinghai; Chen, Jianhui; Birks, H John B; Liu, Jianbao; Zhang, Shengrui; Jin, Liya; An, Chengbang; Telford, Richard J; Cao, Xianyong; Wang, Zongli; Zhang, Xiaojian; Selvaraj, Kandasamy; Lu, Houyuan; Li, Yuecong; Zheng, Zhuo; Wang, Haipeng; Zhou, Aifeng; Dong, Guanghui; Zhang, Jiawu; Huang, Xiaozhong; Bloemendal, Jan; Rao, Zhiguo

    2015-06-18

    The lack of a precisely-dated, unequivocal climate proxy from northern China, where precipitation variability is traditionally considered as an East Asian summer monsoon (EASM) indicator, impedes our understanding of the behaviour and dynamics of the EASM. Here we present a well-dated, pollen-based, ~20-yr-resolution quantitative precipitation reconstruction (derived using a transfer function) from an alpine lake in North China, which provides for the first time a direct record of EASM evolution since 14.7 ka (ka = thousands of years before present, where the "present" is defined as the year AD 1950). Our record reveals a gradually intensifying monsoon from 14.7-7.0 ka, a maximum monsoon (30% higher precipitation than present) from ~7.8-5.3 ka, and a rapid decline since ~3.3 ka. These insolation-driven EASM trends were punctuated by two millennial-scale weakening events which occurred synchronously to the cold Younger Dryas and at ~9.5-8.5 ka, and by two centennial-scale intervals of enhanced (weakened) monsoon during the Medieval Warm Period (Little Ice Age). Our precipitation reconstruction, consistent with temperature changes but quite different from the prevailing view of EASM evolution, points to strong internal feedback processes driving the EASM, and may aid our understanding of future monsoon behaviour under ongoing anthropogenic climate change.

  6. Asian summer monsoon variability during the last two millennia

    NASA Astrophysics Data System (ADS)

    Chawchai, Sakonvan; Chabangborn, Akkaneewut; Fritz, Sherilyn; Blaauw, Maarten; Löwemark, Ludvig; Reimer, Paula J.; Krusic, Paul J.; Väliranta, Minna; Mörth, Carl-Magnus; Wohlfarth, Barbara

    2014-05-01

    The Southeast Asian mainland is located in the central path of the Asian summer monsoon, a region where paleoclimatic data are still sparse. Here we report a new detailed reconstruction of monsoon variability during the past 2000 years from a multi-proxy sediment record (TOC, C/N, δ13C, δ15N, Si, K, Ti elemental data, biogenic silica and fossil plant remains) from Lake Pa Kho in northeast Thailand. We infer a stronger summer monsoon between BC 200 - AD 400 and AD 800 - 1350, a weaker summer monsoon AD 400 - 800, and fluctuating moisture availability AD 1350 - 1550. Increased run-off after AD 1750 can be linked to agricultural intensification in the region. Placed in a wider context our high-resolution data set contributes important information regarding abrupt shifts in hydroclimatic conditions, spatial patterns of monsoon variability, and variations in the position of the ITCZ across SE Asia during the last two millennia. These paleoclimatic shifts may have contributed to the rise and fall of Iron Age and Khmer societies.

  7. Indian monsoon variability on millennial-orbital timescales.

    PubMed

    Kathayat, Gayatri; Cheng, Hai; Sinha, Ashish; Spötl, Christoph; Edwards, R Lawrence; Zhang, Haiwei; Li, Xianglei; Yi, Liang; Ning, Youfeng; Cai, Yanjun; Lui, Weiguo Lui; Breitenbach, Sebastian F M

    2016-04-13

    The Indian summer monsoon (ISM) monsoon is critical to billions of people living in the region. Yet, significant debates remain on primary ISM drivers on millennial-orbital timescales. Here, we use speleothem oxygen isotope (δ(18)O) data from Bittoo cave, Northern India to reconstruct ISM variability over the past 280,000 years. We find strong coherence between North Indian and Chinese speleothem δ(18)O records from the East Asian monsoon domain, suggesting that both Asian monsoon subsystems exhibit a coupled response to changes in Northern Hemisphere summer insolation (NHSI) without significant temporal lags, supporting the view that the tropical-subtropical monsoon variability is driven directly by precession-induced changes in NHSI. Comparisons of the North Indian record with both Antarctic ice core and sea-surface temperature records from the southern Indian Ocean over the last glacial period do not suggest a dominant role of Southern Hemisphere climate processes in regulating the ISM variability on millennial-orbital timescales.

  8. Indian monsoon variability on millennial-orbital timescales

    PubMed Central

    Kathayat, Gayatri; Cheng, Hai; Sinha, Ashish; Spötl, Christoph; Edwards, R. Lawrence; Zhang, Haiwei; Li, Xianglei; Yi, Liang; Ning, Youfeng; Cai, Yanjun; Lui, Weiguo Lui; Breitenbach, Sebastian F. M.

    2016-01-01

    The Indian summer monsoon (ISM) monsoon is critical to billions of people living in the region. Yet, significant debates remain on primary ISM drivers on millennial-orbital timescales. Here, we use speleothem oxygen isotope (δ18O) data from Bittoo cave, Northern India to reconstruct ISM variability over the past 280,000 years. We find strong coherence between North Indian and Chinese speleothem δ18O records from the East Asian monsoon domain, suggesting that both Asian monsoon subsystems exhibit a coupled response to changes in Northern Hemisphere summer insolation (NHSI) without significant temporal lags, supporting the view that the tropical-subtropical monsoon variability is driven directly by precession-induced changes in NHSI. Comparisons of the North Indian record with both Antarctic ice core and sea-surface temperature records from the southern Indian Ocean over the last glacial period do not suggest a dominant role of Southern Hemisphere climate processes in regulating the ISM variability on millennial-orbital timescales. PMID:27071753

  9. East Asian summer monsoon precipitation variability since the last deglaciation

    NASA Astrophysics Data System (ADS)

    Chen, Fahu; Xu, Qinghai; Chen, Jianhui; Birks, H. John B.; Liu, Jianbao; Zhang, Xiaojian; Jin, Liya

    2016-04-01

    The lack of a precisely-dated, unequivocal climate proxy from northern China, where precipitation variability is traditionally considered as an East Asian summer monsoon (EASM) indicator, impedes our understanding of the behaviour and dynamics of the EASM. Here we present a well-dated, pollen-based, ~20-yr-resolution quantitative precipitation reconstruction (derived using a transfer function) from an alpine lake in North China, which provides for the first time a direct record of EASM evolution since 14.7 ka (ka=thousands of years before present, where the "present" is defined as the year AD 1950). Our record reveals a gradually intensifying monsoon from 14.7-7.0 ka, a maximum monsoon (30% higher precipitation than present) from ~7.8-5.3 ka, and a rapid decline since ~3.3 ka. These insolation-driven EASM trends were punctuated by two millennial-scale weakening events which occurred synchronously to the cold Younger Dryas and at ~9.5-8.5 ka, and by two centennial-scale intervals of enhanced (weakened) monsoon during the Medieval Warm Period (Little Ice Age). Our precipitation reconstruction, consistent with temperature changes but quite different from the prevailing view of EASM evolution, points to strong internal feedback processes driving the EASM, and may aid our understanding of future monsoon behaviour under ongoing anthropogenic climate change.

  10. Asian monsoons in a late Eocene greenhouse world.

    PubMed

    Licht, A; van Cappelle, M; Abels, H A; Ladant, J-B; Trabucho-Alexandre, J; France-Lanord, C; Donnadieu, Y; Vandenberghe, J; Rigaudier, T; Lécuyer, C; Terry, D; Adriaens, R; Boura, A; Guo, Z; Soe, Aung Naing; Quade, J; Dupont-Nivet, G; Jaeger, J-J

    2014-09-25

    The strong present-day Asian monsoons are thought to have originated between 25 and 22 million years (Myr) ago, driven by Tibetan-Himalayan uplift. However, the existence of older Asian monsoons and their response to enhanced greenhouse conditions such as those in the Eocene period (55-34 Myr ago) are unknown because of the paucity of well-dated records. Here we show late Eocene climate records revealing marked monsoon-like patterns in rainfall and wind south and north of the Tibetan-Himalayan orogen. This is indicated by low oxygen isotope values with strong seasonality in gastropod shells and mammal teeth from Myanmar, and by aeolian dust deposition in northwest China. Our climate simulations support modern-like Eocene monsoonal rainfall and show that a reinforced hydrological cycle responding to enhanced greenhouse conditions counterbalanced the negative effect of lower Tibetan relief on precipitation. These strong monsoons later weakened with the global shift to icehouse conditions 34 Myr ago.

  11. Linear Prediction of Indian Monsoon Rainfall(.

    NASA Astrophysics Data System (ADS)

    Delsole, Timothy; Shukla, J.

    2002-12-01

    This paper proposes a strategy for selecting the best linear prediction model for Indian monsoon rainfall. In this strategy, a cross-validation procedure first screens out all models that perform poorly on independent data, then the error variance of every remaining model is compared to that of every other model to test whether the difference in error variances is statistically significant. This strategy is shown to produce better forecasts on average than selecting either the model that utilizes all predictors, the model that explains the most variance in the independent data, or the model with the most favorable statistic suggested by Mallow. All of the model selection criteria suggest that regression models based on two to three predictors produce better forecasts on average than regression models using a larger number of predictors. For the period up to 1967, the forecast strategy selected the prior climatology as the best predictor. For the period 1967 to the present, the strategy performed better than forecasts based on the prior climatology and all other methodologies investigated. Indexes of Pacific Ocean temperature in the Tropics (called Niño-3) and indexes of pressure fluctuations in the Northern Atlantic (called NAO), at 1-6 lead months, failed to provide prediction models that performed better on average than a prediction based on the antecedent climatology. Forecasts based on the prior 25-yr climatology had especially high skill during the recent period 1989-2000, a fact that appears to be a mere coincidence, but which may be relevant to interpreting the skill of the power regression model currently used by the India Meteorological Department.

  12. Carbon dioxide emissions from Indian monsoonal estuaries

    NASA Astrophysics Data System (ADS)

    Sarma Vedula, VSS

    2012-07-01

    The oceans act as a net sink for atmospheric CO2, however, the role of coastal bodies on global CO2 fluxes remains unclear due to lack of data. The estimated absorption of CO2 from the continental shelves, with limited data, is 0.22 to 1.0 PgC/y, and of CO2 emission by estuaries to the atmosphere is 0.27 PgC/y. The estimates from the estuaries suffer from large uncertainties due to large variability and lack of systematic data collection. It is especially true for Southeast Asian estuaries as the biogeochemical cycling of material are different due to high atmospheric temperature, seasonality driven by monsoons, seasonal discharge etc. In order to quantify CO2 emissions from the Indian estuaries, samples were collected at 27 estuaries all along the Indian coast during discharge wet and dry periods. The emissions of CO2 to the atmosphere from Indian estuaries were 4-5 times higher during wet than dry period. The pCO2 ranged between ~300 and 18492 microatm which were within the range of world estuaries. The mean pCO2 and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO2 fluxes from the Indian estuaries, together with dry period data available in the literature, amounts to 1.92 TgC which is >10 times less than that from the European estuaries. The low CO2 fluxes from the Indian estuaries are attributed to low flushing rates and less human settlements along the banks of the Indian estuaries.

  13. Management of low back pain in computer users: A multidisciplinary approach

    PubMed Central

    Shete, Kiran M.; Suryawanshi, Prachi; Gandhi, Neha

    2012-01-01

    Background: Low back pain is a very common phenomenon in computer users. More than 80% people using computers for more than 4 h complain of back pain. Objective: To compare the effectiveness of multidisciplinary treatment approach and conventional treatment approach amongst computer users. Materials and Methods: A prospective interventional study was carried out at a private spine clinic amongst the computer users with the complaint of low back pain. The study participants were randomly distributed in two groups. The first group comprised the study participants treated by conventional approach and the second group was treated by multidisciplinary approach. Primary outcomes analyzed were pain intensity, sick leave availed, and quality of life. Statistical analysis was done using proportions, unpaired “t” test, and Wilcoxon signed-rank test. Results: Totally 44 study participants were randomly assigned to groups I and II, and each group had 22 study participants. Intensity of pain was reduced significantly in the group treated by multidisciplinary approach (t = 5.718; P = 0.0001). Similarly only 4 (19.19%) of the study participants of the group treated by multidisciplinary approach availed sick leave due to low back pain, while 14 (63.63%) study participants availed sick leave in the other group (P = 0.02). The quality of life amongst the study participants treated by multidisciplinary approach was significantly improved compared to the group treated by conventional approach (t = 7.037; P = 0.0001). Conclusion and Recommendation: The multidisciplinary treatment approach was better than the conventional treatment approach in low back pain cases when some factors like pain and quality of life were assessed. The multidisciplinary approach for treatment of low back pain should be promoted over conventional approach. Larger studies are required to confirm the findings in different settings. PMID:23741122

  14. Reconstructing monsoon dynamics on the Tibetan Plateau using ostracod shell chemistry

    NASA Astrophysics Data System (ADS)

    Boerner, N.; De Baere, B.; Yang, Q.; Francois, R. H. G. M.; Jochum, K. P.; Frenzel, P.; Schwalb, A.

    2014-12-01

    Ostracod shells have widely been used as source material for geochemical analysis of stable isotope and trace element composition in paleolimnological reconstruction of lake hydrochemistry and climate as they provide insight into past water balance and solute evolution of lakes. During five fieldtrips to the Tibetan Plateau, taking place between 2008 and 2012, we collected live and sub-recent ostracods from 333 sites. Hydrochemical parameters, such as temperature, electrical conductivity, pH as well as major and minor ion concentrations were measured at each site and show high variability between sites. Adult intact individuals from the most common ostracod taxa were selected and their shell chemistry analyzed. The trace elemental data for the living ostracods compared to the hydrological data provides a calibration dataset for further hydrological and thus climatological reconstruction. Mg/Ca, Sr/Ca and Ba/Ca ratios in ostracod shells provide information about past water temperature and salinity resulting from changes in precipitation vs. evaporation ratios and monsoon activity. Furthermore, Mn/Ca, Fe/Ca and U/Ca ratios are being explored as redox indicators to reconstruct oxygenation cycles. To reconstruct the monsoon dynamics on the Tibetan Plateau, sediment cores from different lakes on an east-west transect were taken: two long sediment cores from lakes Nam Co and Tangra Yumco, covering the past 20,000 years, and a short core from Lake Taro Co. The lakes feature an alkaline environment but show significant differences in their electrical conductivity ranging from 0.99 mS/cm (Taro Co) and 1.8 mS/cm (Nam Co) to 12 mS/cm (Tangra Yumco). The chemical composition of valves of the most common ostracod species in these lakes, Leucocytherella sinensis, was analyzed using laser ablation ICP-MS. The reconstruction provides a more extensive insight in past precipitation - evaporation balance and lake level change and provides clues about the interaction between the

  15. Reduction of monsoon rainfall in response to past and future land use and land cover changes

    NASA Astrophysics Data System (ADS)

    Quesada, Benjamin; Devaraju, Narayanappa; Noblet-Ducoudré, Nathalie; Arneth, Almut

    2017-01-01

    Land use and land cover changes (LULCC) can have significant biophysical impacts on regional precipitation, including monsoon rainfall. Using global simulations with and without LULCC from five general circulation models, under the Representative Concentration Pathway 8.5 scenario, we find that future LULCC significantly reduce monsoon precipitation in at least four (out of eight) monsoon regions. While monsoon rainfalls are likely to intensify under future global warming, we estimate that biophysical effects of LULCC substantially weaken future projections of monsoons' rainfall by 9% (Indian region), 12% (East Asian), 32% (South African), and 41% (North African), with an average of 30% for projections across the global monsoon region. A similar strong contribution is found for biophysical effects of past LULCC to monsoon rainfall changes since the preindustrial period. Rather than remote effects, local land-atmosphere interactions, implying a decrease in evapotranspiration, soil moisture, and clouds along with more anticyclonic conditions, could explain this reduction in monsoon rainfall.

  16. The role of northern Arabian Sea surface temperature biases in CMIP5 model simulations and future projections of Indian summer monsoon rainfall

    NASA Astrophysics Data System (ADS)

    Levine, Richard C.; Turner, Andrew G.; Marathayil, Deepthi; Martin, Gill M.

    2013-07-01

    Many climate models have problems simulating Indian summer monsoon rainfall and its variability, resulting in considerable uncertainty in future projections. Problems may relate to many factors, such as local effects of the formulation of physical parametrisation schemes, while common model biases that develop elsewhere within the climate system may also be important. Here we examine the extent and impact of cold sea surface temperature (SST) biases developing in the northern Arabian Sea in the CMIP5 multi-model ensemble, where such SST biases are shown to be common. Such biases have previously been shown to reduce monsoon rainfall in the Met Office Unified Model (MetUM) by weakening moisture fluxes incident upon India. The Arabian Sea SST biases in CMIP5 models consistently develop in winter, via strengthening of the winter monsoon circulation, and persist into spring and summer. A clear relationship exists between Arabian Sea cold SST bias and weak monsoon rainfall in CMIP5 models, similar to effects in the MetUM. Part of this effect may also relate to other factors, such as forcing of the early monsoon by spring-time excessive equatorial precipitation. Atmosphere-only future time-slice experiments show that Arabian Sea cold SST biases have potential to weaken future monsoon rainfall increases by limiting moisture flux acceleration through non-linearity of the Clausius-Clapeyron relationship. Analysis of CMIP5 model future scenario simulations suggests that such effects are small compared to other sources of uncertainty, although models with large Arabian Sea cold SST biases may suppress the range of potential outcomes for changes to future early monsoon rainfall.

  17. Environmental status of groundwater affected by chromite ore processing residue (COPR) dumpsites during pre-monsoon and monsoon seasons.

    PubMed

    Matern, Katrin; Weigand, Harald; Singh, Abhas; Mansfeldt, Tim

    2017-02-01

    Chromite ore processing residue (COPR) is generated by the roasting of chromite ores for the extraction of chromium. Leaching of carcinogenic hexavalent chromium (Cr(VI)) from COPR dumpsites and contamination of groundwater is a key environmental risk. The objective of the study was to evaluate Cr(VI) contamination in groundwater in the vicinity of three COPR disposal sites in Uttar Pradesh, India, in the pre-monsoon and monsoon seasons. Groundwater samples (n = 57 pre-monsoon, n = 70 monsoon) were taken in 2014 and analyzed for Cr(VI) and relevant hydrochemical parameters. The site-specific ranges of Cr(VI) concentrations in groundwater were <0.005 to 34.8 mg L(-1) (Rania), <0.005 to 115 mg L(-1) (Chhiwali), and <0.005 to 2.0 mg L(-1) (Godhrauli). Maximum levels of Cr(VI) were found close to the COPR dumpsites and significantly exceeded safe drinking water limits (0.05 mg L(-1)). No significant dependence of Cr(VI) concentration on monsoons was observed.

  18. Is the Indian summer monsoon stable against global change?

    NASA Astrophysics Data System (ADS)

    Zickfeld, K.; Knopf, B.; Petoukhov, V.; Schellnhuber, H. J.

    2005-08-01

    The stability of the Indian summer monsoon is investigated by means of a box model of the tropical atmosphere. At the heart of this model is the moisture-advection feedback which allows for the existence of two stable regimes: besides the ``wet'' summer monsoon, a stable state exists which is characterized by low precipitation. The model is employed for the identification of changes in the qualitative systems behavior in response to changes in boundary conditions. The most notable result is the occurrence of saddle-node bifurcations against changes in those quantities which govern the heat balance of the system, i.e., the planetary albedo, the insolation, and the CO2 concentration. These findings are remarkable insofar as they indicate that anthropogenic perturbations of the planetary albedo, such as sulphur emissions and/or land-use changes, or natural variations in insolation and CO2 concentration could trigger abrupt transitions between different monsoon regimes.

  19. Observational relationships between aerosol and Asian monsoon rainfall, and circulation

    NASA Astrophysics Data System (ADS)

    Lau, K.-M.; Kim, K.-M.

    2006-11-01

    Preliminary observational evidences are presented showing that the Indian subcontinent and surrounding regions are subject to heavy loading of absorbing aerosols, i.e., dust and black carbon, which possess spatial and temporal variability that are closely linked to those of the Asian monsoon water cycle. Consistent with the Elevated Heat Pump hypothesis, we find that increased loading of absorbing aerosols over the Indo-Gangetic Plain in the pre-monsoon season is associated with a) increased heating of the upper troposphere, with the formation of a warm-core upper level anticyclone over the Tibetan Plateau in April-May, b) an advance of the monsoon rainy season in northern India in May, and c) subsequent increased rainfall over the Indian subcontinent, and decreased rainfall over East Asia in June-July.

  20. A satellite-based 13-year climatology of net cloud radiative forcing over the Indian monsoon region

    NASA Astrophysics Data System (ADS)

    Saud, Trailokya; Dey, Sagnik; Das, Sushant; Dutta, Soumi

    2016-12-01

    We present a satellite-based 13-year (Mar. 2000-Feb. 2013) climatology of net cloud radiative forcing (CRF) over the Indian monsoon region (0-40°N, 60-100°E) using the Clouds and Earth's Radiant Energy System (CERES) radiation data and explained the net CRF variability in terms of cloud properties retrieved by Moderate Resolution Imaging Spectroradiometer (MODIS). Mean (± 1σ) seasonal shortwave (SW) CRF values averaged over the region are - 82.7 ± 24.5, - 32.1 ± 12.1, - 17.2 ± 5.3 and - 30.2 ± 16.2 W m- 2 respectively for the monsoon (JJAS), post-monsoon (ON), winter (DJF) and pre-monsoon (MAM) seasons; while the corresponding longwave (LW) CRF values are 53.7 ± 14.2, 27.9 ± 10.0, 15.8 ± 7.0 and 25.2 ± 9.1 W m- 2. Regional analysis reveals the largest (least) negative net CRF over the northeast (northwest) rainfall homogeneous zone throughout the year due to the dominance of optically thick high clouds (low cloud fraction, fc). Mean JJAS fc is found to increase (by > 0.01 per year) over large parts of the Arabian Sea, Bay of Bengal and the northwest region. Mean annual net CRF values for cumulus, stratocumulus and stratus (low level), altocumulus, altostratus and nimbostratus (mid-level clouds) and cirrus, cirrostratus and deep-convective (high level) clouds over the Indian monsoon region are estimated to be - 0.8, - 4.7, - 6.9, + 3.3, - 6.3, - 23.3, + 5.4, - 23.3 and - 42.1 W m- 2 respectively. Across a wide range of cloud optical depth (COD) and fc < 0.6, near cancellation of SW cooling by LW warming, is observed for low clouds. Net CRF drops below - 15 W m- 2 for clouds evolving above 400 hPa, mainly in the monsoon season. Our results demonstrate that net CRF variability in the Indian monsoon region can be explained by variability in Cloud Top Pressure (CTP), COD and fc. The study highlights the need for resolving a multi-layer cloud field in the future.

  1. Abnormal monsoon years and their control on erosion and sediment flux in the high, arid northwest Himalaya

    NASA Astrophysics Data System (ADS)

    Bookhagen, Bodo; Thiede, Rasmus C.; Strecker, Manfred R.

    2005-02-01

    The interplay between topography and Indian summer monsoon circulation profoundly controls precipitation distribution, sediment transport, and river discharge along the Southern Himalayan Mountain Front (SHF). The Higher Himalayas form a major orographic barrier that separates humid sectors to the south and arid regions to the north. During the Indian summer monsoon, vortices transport moisture from the Bay of Bengal, swirl along the SHF to the northwest, and cause heavy rainfall when colliding with the mountain front. In the eastern and central parts of the Himalaya, precipitation measurements derived from passive microwave analysis (SSM/I) show a strong gradient, with high values at medium elevations and extensive penetration of moisture along major river valleys into the orogen. The end of the monsoonal conveyer belt is near the Sutlej Valley in the NW Himalaya, where precipitation is lower and rainfall maxima move to lower elevations. This region thus comprises a climatic transition zone that is very sensitive to changes in Indian summer monsoon strength. To constrain magnitude, temporal, and spatial distribution of precipitation, we analyzed high-resolution passive microwave data from the last decade and identified an abnormal monsoon year (AMY) in 2002. During the 2002 AMY, violent rainstorms conquered orographic barriers and penetrated far into otherwise arid regions in the northwest Himalaya at elevations in excess of 3 km asl. While precipitation in these regions was significantly increased and triggered extensive erosional processes (i.e., debris flows) on sparsely vegetated, steep hillslopes, mean rainfall along the low to medium elevations was not significantly greater in magnitude. This shift may thus play an important role in the overall sediment flux toward the Himalayan foreland. Using extended precipitation and sediment flux records for the last century, we show that these events have a decadal recurrence interval during the present-day monsoon

  2. Anomalies in the South American Monsoon Induced by Aerosols

    NASA Technical Reports Server (NTRS)

    Lau, K. M. William; Kyu-Mong, Kim

    2007-01-01

    We have investigated the direct effects of aerosols on the water cycle of the South American monsoon using the NASA finite-volume general circulation model (fvGCM). Global aerosol forcings are computed from radiative transfer functions derived from global distributions of five species of aerosols, i.e., dust, black carbon, organic carbon, sulphate and sea salt from the Goddard Chemistry Aerosol Radiation Transport (GOCART) model. Comparing fvGCM experiments without aerosol forcing, and with different combinations of aerosol forcing, we evaluate the impacts of aerosol direct heating on the onset, maintenance and evolution of the South American summer monsoon. We find that during the pre-monsoon season (September-October-November) Saharan dust contribute to heating of the atmosphere over the central and eastern equatorial Atlantic/Africa region through the elevated heat pump mechanism. The heating generates an anomalous Walker circulation with sinking motion, and low level northeasterlies over the Caribbean and northwestern South America. The low level flow is blocked by the Andes, and turn south and southeastward, increasing the low level jet (LLJ) along the eastern slope of the Andes. The increased LLJ transports more moisture from the Atlantic and the Amazon, enhancing the moisture convergence over subtropical land regions of South America. The moisture convergence was further accelerated by atmospheric heating by biomass burning over the Amazon. The net results of the dust and biomass heating are: a) an advance of the monsoon rainy season, b) an enhanced LLJ and c) a shifting the South America monsoon land precipitation equatorward, with increased rain over southern Brazil and reduced rain over the La Plata basin. ramifications of this elevated heating heat pump mechanism in aerosol monsoon water cycle on climate variability and change will be discussed. The ramifications of this "elevated heating heat pump" mechanism in aerosol monsoom water cycle on climate

  3. South Asian summer monsoon variability in a model with doubled atmospheric carbon dioxide concentration

    SciTech Connect

    Meehl, G.A.; Washington, W.M. )

    1993-05-21

    Doubled atmospheric carbon dioxide concentration in a global coupled ocean-atmosphere climate model produced increased surface temperatures and evaporation and greater mean precipitation in the south Asian summer monsoon region. As a partial consequence, interannual variability of area-averaged monsoon rainfall was enhanced. Consistent with the climate sensitivity results from the model, observations showed a trend o