Science.gov

Sample records for monsoon multidisciplinary analysis

  1. New approach for aerosol profiling with a lidar onboard an ultralight aircraft: application to the African Monsoon Multidisciplinary Analysis.

    PubMed

    Chazette, Patrick; Sanak, Joseph; Dulac, François

    2007-12-15

    A new airborne instrumental payload has been designed for an ultralight aircraft to determine the vertical profile of aerosol optical properties. It is based on Lidar Aérosols UltraViolet Aéroporté (LAUVA), a compact backscattering lidar system emitting at the wavelength of 355 nm. We operated this airborne configuration in the Sahel from the city of Niamey (Niger) during the first campaign of the African Monsoon Multidisciplinary Analysis (AMMA) in January-February 2006, when aerosols from both soil dust and savannah fires cause large visibility reductions. We take advantage of the lidar capability of pointing in different directions for retrieving the vertical profile of the aerosol backscatter to extinction ratio (BER). A synergy with a scatterometer (880 nm) and a ground-based sunphotometer allows us to further determine the vertical profile of Angström exponent (a). We identify three types of aerosol layers up to about 5 km below the free troposphere, dominated by biomass burning (BB) particles, mineral dust (D) particles, and a mixing between BB and D particles, respectively, associated with BER (a) values close to 0.008 sr(-1) (1.5), 0.025 sr(-1) (0), and 0.015 sr(-1) (0.4-1).

  2. 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.

  3. 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.

  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. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. Global sensitivity analysis of the Indian monsoon during the Pleistocene

    NASA Astrophysics Data System (ADS)

    Araya-Melo, P. A.; Crucifix, M.; Bounceur, N.

    2015-01-01

    The sensitivity of the Indian monsoon to the full spectrum of climatic conditions experienced during the Pleistocene is estimated using the climate model HadCM3. The methodology follows a global sensitivity analysis based on the emulator approach of Oakley and O'Hagan (2004) implemented following a three-step strategy: (1) development of an experiment plan, designed to efficiently sample a five-dimensional input space spanning Pleistocene astronomical configurations (three parameters), CO2 concentration and a Northern Hemisphere glaciation index; (2) development, calibration and validation of an emulator of HadCM3 in order to estimate the response of the Indian monsoon over the full input space spanned by the experiment design; and (3) estimation and interpreting of sensitivity diagnostics, including sensitivity measures, in order to synthesise the relative importance of input factors on monsoon dynamics, estimate the phase of the monsoon intensity response with respect to that of insolation, and detect potential non-linear phenomena. By focusing on surface temperature, precipitation, mixed-layer depth and sea-surface temperature over the monsoon region during the summer season (June-July-August-September), we show that precession controls the response of four variables: continental temperature in phase with June to July insolation, high glaciation favouring a late-phase response, sea-surface temperature in phase with May insolation, continental precipitation in phase with July insolation, and mixed-layer depth in antiphase with the latter. CO2 variations control temperature variance with an amplitude similar to that of precession. The effect of glaciation is dominated by the albedo forcing, and its effect on precipitation competes with that of precession. Obliquity is a secondary effect, negligible on most variables except sea-surface temperature. It is also shown that orography forcing reduces the glacial cooling, and even has a positive effect on precipitation

  14. 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.

  15. Global sensitivity analysis of Indian Monsoon during the Pleistocene

    NASA Astrophysics Data System (ADS)

    Araya-Melo, P. A.; Crucifix, M.; Bounceur, N.

    2014-04-01

    The sensitivity of Indian Monsoon to the full spectrum of climatic conditions experienced during the Pleistocene is estimated using the climate model HadCM3. The methodology follows a global sensitivity analysis based on the emulator approach of Oakley and O'Hagan (2004) implemented following a three-step strategy: (1) develop an experiment plan, designed to efficiently sample a 5-dimensional input space spanning Pleistocene astronomical configurations (3 parameters), CO2 concentration and a Northern Hemisphere glaciation index, (2) develop, calibrate and validate an emulator of HadCM3, in order to estimate the response of the Indian Monsoon over the full input space spanned by the experiment design, and (3) estimate and interpret sensitivity diagnostics, including sensitivity measures, in order to synthesize the relative importance of input factors on monsoon dynamics, estimate the phase of the monsoon intensity response with respect to that of insolation, and detect potential non-linear phenomena. Specifically, we focus on four variables: summer (JJAS) temperature and precipitation over North India, and JJAS sea-surface temperature and mixed-layer depth over the north-western side of the Indian ocean. It is shown that precession controls the response of four variables: continental temperature in phase with June to July insolation, high glaciation favouring a late-phase response, sea-surface temperature in phase with May insolation, and continental precipitation in phase with July insolation, and mixed-layer depth in antiphase with the latter. CO2 variations controls temperature variance with an amplitude similar to that of precession. The effect of glaciation is dominated by the albedo forcing, and its effect on precipitation competes with that of precession. Obliquity is a secondary effect, negligible on most variables except sea-surface temperature. It is also shown that orography forcing reduces the glacial cooling, and even has a positive effect on

  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. 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.

    2014-12-01

    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.

  18. 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.

  19. Regional analysis of convective systems during the West African monsoon

    NASA Astrophysics Data System (ADS)

    Guy, Bradley Nicholas

    The West African monsoon (WAM) occurs during the boreal summer and is responsible for a majority of precipitation in the northern portion of West Africa. A distinct shift of precipitation, often driven by large propagating mesoscale convective systems, is indicated from satellite observations. Excepting the coarser satellite observations, sparse data across the continent has prevented understanding of mesoscale variability of these important systems. The interaction between synoptic and mesoscale features appears to be an important part of the WAM system. Without an understanding of the mesoscale properties of precipitating systems, improved understanding of the feedback mechanism between spatial scales cannot be attained. Convective and microphysical characteristics of West African convective systems are explored using various observational data sets. Focus is directed toward meso -alpha and -beta scale convective systems to improve our understanding of characteristics at this spatial scale and contextualize their interaction with the larger-scale. Ground-based radar observations at three distinct geographical locations in West Africa along a common latitudinal band (Niamey, Niger [continental], Kawsara, Senegal [coastal], and Praia, Republic of Cape Verde [maritime]) are analyzed to determine convective system characteristics in each domain during a 29 day period in 2006. Ancillary datasets provided by the African Monsoon Multidisciplinary Analyses (AMMA) and NASA-AMMA (NAMMA) field campaigns are also used to place the radar observations in context. Results show that the total precipitation is dominated by propagating mesoscale convective systems. Convective characteristics vary according to environmental properties, such as vertical shear, CAPE, and the degree of synoptic forcing. Data are bifurcated based on the presence or absence of African easterly waves. In general, African easterly waves appear to enhance mesoscale convective system strength

  20. Asian summer monsoon rainfall predictability: a predictable mode analysis

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Lee, June-Yi; Xiang, Baoqiang

    2015-01-01

    To what extent the Asian summer monsoon (ASM) rainfall is predictable has been an important but long-standing issue in climate science. Here we introduce a predictable mode analysis (PMA) method to estimate predictability of the ASM rainfall. The PMA is an integral approach combining empirical analysis, physical interpretation and retrospective prediction. The empirical analysis detects most important modes of variability; the interpretation establishes the physical basis of prediction of the modes; and the retrospective predictions with dynamical models and physics-based empirical (P-E) model are used to identify the "predictable" modes. Potential predictability can then be estimated by the fractional variance accounted for by the "predictable" modes. For the ASM rainfall during June-July-August, we identify four major modes of variability in the domain (20°S-40°N, 40°E-160°E) during 1979-2010: (1) El Niño-La Nina developing mode in central Pacific, (2) Indo-western Pacific monsoon-ocean coupled mode sustained by a positive thermodynamic feedback with the aid of background mean circulation, (3) Indian Ocean dipole mode, and (4) a warming trend mode. We show that these modes can be predicted reasonably well by a set of P-E prediction models as well as coupled models' multi-model ensemble. The P-E and dynamical models have comparable skills and complementary strengths in predicting ASM rainfall. Thus, the four modes may be regarded as "predictable" modes, and about half of the ASM rainfall variability may be predictable. This work not only provides a useful approach for assessing seasonal predictability but also provides P-E prediction tools and a spatial-pattern-bias correction method to improve dynamical predictions. The proposed PMA method can be applied to a broad range of climate predictability and prediction problems.

  1. [Causes of problems in multidisciplinary bitemark analysis].

    PubMed

    Przystańska, Agnieszka; Lorkiewicz-Muszyńska, Dorota; Glapiński, Mariusz; Swiderski, Paweł; Łabecka, Marzena; Zaba, Czesław

    2013-01-01

    Since a successful bitemark analysis depends on many factors, it is important that the phases preceding the analysis be carried out as thoroughly as possible. Interpretive errors in the analysis arise primarily from the complex nature of bitemarks, but also as a result of faulty research methodology, false assumptions or technical errors made during the identification and documentation process. The key role is played by qualifications, knowledge and experience of experts involved in the investigations. In case bitemarks are detected, it is recommended to seek consultations by forensic odontologists or members of an interdisciplinary team experienced in bitemark analysis. The thus obtained information allows for gathering evidence guaranteeing a reliable expert opinion. PMID:24672898

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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

  14. Empirical Orthogonal Function (EOF) analysis of monsoon rainfall and satellite-observed outgoing long-wave radiation for Indian monsoon: a comparative study

    NASA Astrophysics Data System (ADS)

    Singh, C. V.

    The present study involves the use of Empirical Orthogonal Function (EOF) analysis/Principal Component Analysis (PCA) to compare the dominant rainfall patterns from normal rainfall records over India, coupled with the major modes of the Outgoing Long-wave Radiation (OLR) data for the period (1979-1988) during the monsoon period (June-September). To understand the intraseasonal and interannual variability of the monsoon rainfall, daily and seasonal anomalies have been obtained by using the (EOF) analysis. Importantly, pattern characteristics of seasonal monsoon rainfall covering 68 stations in India are highlighted. The purpose is to ascertain the nature of rainfall distribution over the Indian continent. Based on this, the percentage of variance for both the rainfall and OLR data is examined. OLR has a higher spatial coherence than rainfall. The first principal component of rainfall data shows high positive values, which are concentrated over northeast as well as southeast, whereas for the OLR, the area of large positive values is concentrated over northwest and lower value over south India apart from the Indian ocean. The first five principal components explain 92.20% of the total variance for the rainfall and 99.50% of the total variance for the outgoing long-wave radiation. The relationship between monsoon rainfall and Southern Oscillations has also been examined and for the Southern Oscillations, it is 0.69 for the monsoon season. The El-Niño events mostly occurred during Southern Oscillations, i.e. Walker circulation. It has been found that the average number of low pressure system/low pressure system days play an important role during active (flood) or inactive (drought) monsoon year, but low pressure system days play more important role in comparison to low pressure systems and their ratio are (16:51) and (13:25) respectively. Significantly, the analysis identifies the spatial and temporal pattern characteristics of possible physical significance.

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

    NASA Astrophysics Data System (ADS)

    Wang, Tao; Chen, Jiansheng; Li, Ling

    2016-08-01

    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.

  16. 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

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

    PubMed

    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 (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. PMID:27507656

  18. 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.

  19. 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.

  20. 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.

  1. Predictability of the Indian Summer Monsoon onset through an analysis of variations in surface air temperature and relative humidity during the pre-monsoon season

    NASA Astrophysics Data System (ADS)

    Stolbova, V.; Surovyatkina, E.; Bookhagen, B.; Kurths, J.

    2014-12-01

    The prediction of the Indian Summer monsoon (ISM) onset is one of the vital questions for the Indian subcontinent, as well as for areas directly or indirectly affected by the ISM. In previous studies, the areas used for ISM-onset prediction were often too large (or too small), or did not include all necessary information for the ISM-onset forecasting. Here, we present recent findings that suggest that a climate network approach may help to provide better definitions for areas used for ISM-onset prediction and an overall better ISM-onset prediction. Our analysis focuses on the following domains: North West Pakistan (NP) and the Eastern Ghats (EG) as they have been identified to include important pre-monsoon information for predicting ISM onset dates. Specifically, we focus on the analysis of surface air temperature and relative humidity in both areas that allows us to derive temporal trends and to estimate the ISM onset. We propose an approach, which 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. ISM onset is predicted for 23 out of 27 normal monsoon years (85%) during the past 6 decades. In addition, we show that time series analysis in both areas during the pre-monsoon period reveals indicators whether the forthcoming ISM will be normal or weaker/stronger.

  2. 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.

  3. 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.!

  4. Temporal analysis of rainfall (1871-2012) and drought characteristics over a tropical monsoon-dominated State (Kerala) of India

    NASA Astrophysics Data System (ADS)

    Thomas, Jobin; Prasannakumar, V.

    2016-03-01

    The climate of Kerala is controlled by the monsoon, and the analysis of rainfall and drought scenario, for a period of 141 years (1871-72 to 2011-12), reveals a decreasing trend in southwest monsoon, and increasing trends for post-monsoon-, winter- and pre-monsoon-rainfall. The inconsistent periodicity (2-8 years) of annual- and seasonal-rainfall agrees with the periodicity of El-Nino Southern Oscillation (ENSO). The annual rainfall shows an irregular distribution, and is concentrated roughly in half of the year, which is due to the monsoon-driven climatic seasonality. The rainfall concentration at annual-, southwest monsoon-, and winter-scales exhibits significant decreasing trends, implying decline in the degree of irregularity in annual- and seasonal-rainfall. Temporal distribution as well as severity of the drought events have been analyzed using various drought indicators. The drought pattern is not only related to the rainfall trends, but also to the rainfall concentration (or monthly rainfall heterogeneity). The decreasing rainfall during southwest monsoon contributes to short-term meteorological droughts, which have serious implications on the agricultural sector and water resources of Kerala, while the increasing rainfall during other seasons helps to reduce the drought severity.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. RAMA: Research Moored Array for African - Asian - Australian Monsoon Analysis and Prediction

    NASA Astrophysics Data System (ADS)

    McPhaden, M. J.

    2008-12-01

    The Indian Ocean is unique among the three tropical oceans in that it is blocked at 25N by the Asian land mass. Seasonal heating and cooling over this land mass sets the stage for dramatic monsoon wind reversals and intense summer rains over areas surrounding the basin. These climate variations have significant societal and economic impacts that affect half the world's population. Despite the importance of the Indian Ocean for both the regional and global climate though, it is the most poorly observed and least well understood of the three tropical oceans. This presentation describes the Research Moored Array for African-Asian-Australian Monsoon Analysis and Prediction (RAMA), which has been designed to provide sustained, basin scale time series data in the Indian Ocean for climate research and forecasting. RAMA is intended to complement other satellite and in situ components of the Indian Ocean Observing System and it is being implemented through a coordinated multi- national effort involving institutions in several countries. We will review the scientific rationale, design criteria, and implementation status of RAMA. We will also illustrate some of the important intraseasonal to interannual time scale phenomena in the region observed with new RAMA time series data. Potential applications of the data for forecasting purposes will also be discussed.

  10. RAMA: Research Moored Array for African-Asian-Australian Monsoon Analysis and Prediction

    NASA Astrophysics Data System (ADS)

    McPhaden, M. J.

    2009-05-01

    The Indian Ocean is unique among the three tropical ocean basins in that it is blocked at 25°N by the Asian land mass. Seasonal heating and cooling over this land mass sets the stage for dramatic monsoon wind reversals and intense rains over areas surrounding the basin. These climate variations have significant societal and economic impacts that affect half the world's population. Despite the importance of the Indian Ocean for both the regional and global climate though, it is the most poorly observed and least well understood of the three tropical oceans. This presentation describes the Research Moored Array for African-Asian- Australian Monsoon Analysis and Prediction (RAMA), which has been designed to provide sustained, basin scale time series data in the Indian Ocean for climate research and forecasting. RAMA is intended to complement other satellite and in situ components of the Indian Ocean Observing System and it is being implemented through a coordinated multi-national effort involving institutions in several countries. We will review the scientific rationale, design criteria, and implementation status of RAMA. We will also illustrate some of the important intraseasonal to interannual time scale phenomena in the region observed with new RAMA time series data. Potential applications of the data for forecasting purposes will also be discussed.

  11. Analysis of remote measurements of tropospheric carbon monoxide concentrations made during the 1979 Summer Monsoon Experiment (MONEX)

    NASA Technical Reports Server (NTRS)

    Doherty, G. M.; Newell, R. E.; Reichle, H. G., Jr.

    1986-01-01

    Mixing ratios of tropospheric CO as measured by an aircraft-mounted radiometer over Saudi Arabia, the Arabian Sea, and northern India during May and June 1979 are reported. During early May, exceptionally high CO levels were detected over Saudi Arabia, and strong horizontal gradients in CO mixing ratios were seen to develop over a period of several days. Over the Arabian Sea, mixing ratios of the order of 150 parts per billion by volume were observed before the monsoon onset, and a pronounced decrease in CO was detected toward the equator. Subsequent measurements after the monsoon had become established revealed a consistent decrease in CO mixing ratio across this region. Analysis of aircraft dropsonde data and constant pressure daily streamline charts lend strong support to the hypothesis that this reduction is associated with the influx of CO-poor Southern Hemisphere air in the monsoon southwesterlies.

  12. 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.

  13. 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.

  14. 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.

  15. Monsoon driven changes in phytoplankton populations in the eastern Arabian Sea as revealed by microscopy and HPLC pigment analysis

    NASA Astrophysics Data System (ADS)

    Parab, Sushma G.; Prabhu Matondkar, S. G.; Gomes, H. do R.; Goes, J. I.

    2006-12-01

    Like the rest of the Arabian Sea, the west coast of India is subject to semi-annual wind reversals associated with the monsoon cycle that result in two periods of elevated phytoplankton productivity, one during the northeast (NE) monsoon (November-February) and the other during the southwest (SW) monsoon (June-September). Although the seasonality of phytoplankton biomass in these coastal waters is well known, the abundance and composition of phytoplankton populations associated with this distinct and predictable seasonal cycle is poorly known. Here we present for the first time, the results of a study on the community structure of phytoplankton for this region, derived from HPLC pigment analysis and microscopic cell counts. Our sampling strategy allowed for large spatial and temporal coverage over regions representative of the coastal and offshore waters, and over seasons that included the NE and the SW monsoon. Monthly observations at a fixed coastal station in particular, allowed us to follow changes in phytoplankton community structure associated with the development of anoxia. Together these measurements helped establish a pattern of seasonal change of three major groups of phytoplankton: diatoms, dinoflagellates and cyanobacteria that appeared to be tightly coupled with hydrographic and chemical changes associated with the monsoonal cycle. During the SW monsoon when nitrate concentrations were high, diatoms were dominant but prymnesiophytes were present as well. By October, as nitrate fell to below detection levels and anoxic conditions began to develop on the shelf below the shallow pycnocline, both diatom and prymensiophytes declined sharply giving way to dinoflagellates. In the well oxygenated surface waters, where both nitrate and ammonium were below detection limits, pico-cyanobacterial populations became dominant. During the NE monsoon, a mixed diatom-dinoflagellate population was quickly replaced by blooms of Trichodesmium erythraeum and Noctiluca

  16. Trend analysis and ARIMA modelling of pre-monsoon rainfall data for western India

    NASA Astrophysics Data System (ADS)

    Narayanan, Priya; Basistha, Ashoke; Sarkar, Sumana; Kamna, Sachdeva

    2013-01-01

    Spatial and temporal variability of rainfall over different seasons influence physical, social and economic parameters. Pre-monsoon (March, April and May - MAM) rainfall over the country is highly variable. Since heat lows and convective rainfall in MAM have an impact on the intensity of the ensuing monsoons, hence the pre-monsoon period was chosen for the study. The pre-whitened Mann Kendall test was used to explore presence of rainfall trend during MAM. The results indicate presence of significant (at 10% level) increasing trend in two stations (Ajmer, Bikaner). The practical significance of the change in rainfall was also explored as percentage changes over long term mean, using Theil and Sen's median slope estimator. Forecast using univariate ARIMA model for pre-monsoon months indicates that there is a significant rise in the pre-monsoon rainfall over the northwest part of the country.

  17. 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.

  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. 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.

  20. 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.

  1. 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.

  2. 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.

  3. A climatological analysis of the southwest monsoon rainfall in the Philippines

    NASA Astrophysics Data System (ADS)

    Cruz, F. T.; Narisma, G. T.; Villafuerte, M. Q.; Cheng Chua, K. U.; Olaguera, L. M.

    2013-03-01

    The historical behavior of the southwest monsoon (SWM) rainfall in the Philippines is described using observed rainfall during the months of June to September from 1961 to 2010. Data are obtained from meteorological stations situated in the western half of the country where the impact of SWM is well pronounced. Time series analysis indicates significant decreasing trends from 0.026% to 0.075% per decade in the total SWM rainfall in six of the nine stations (Ambulong, Baguio, Coron, Dagupan, Iba and Vigan) in the past 50 years. A rainfall anomaly index is derived to characterize the inter-annual variability and the influence of the El Niño Southern Oscillation on the SWM rainfall. Results show no above normal rainfall events associated with La Niña years and few occurrences of below normal rainfall associated with El Niño events. Years where the SWM rainfall significantly deviates from its climate mean are also identified. Furthermore, an examination of the rainfall extremes indicate an increasing trend in the number of days without rain, which can be detected with statistical confidence in Ambulong (2.9% per decade), Baguio (5.9% per decade) and Dagupan (4.0% per decade), as well as a decreasing trend in the heavy rainfall days. These findings suggest a climatic change towards a prolonged dry period and an overall decreasing trend in rainfall during the SWM season over western Philippines in the recent decades, which can have serious implications on the country's agricultural sector.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. Using the framework method for the analysis of qualitative data in multi-disciplinary health research

    PubMed Central

    2013-01-01

    Background The Framework Method is becoming an increasingly popular approach to the management and analysis of qualitative data in health research. However, there is confusion about its potential application and limitations. Discussion The article discusses when it is appropriate to adopt the Framework Method and explains the procedure for using it in multi-disciplinary health research teams, or those that involve clinicians, patients and lay people. The stages of the method are illustrated using examples from a published study. Summary Used effectively, with the leadership of an experienced qualitative researcher, the Framework Method is a systematic and flexible approach to analysing qualitative data and is appropriate for use in research teams even where not all members have previous experience of conducting qualitative research. PMID:24047204

  11. 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.

  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. 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.

  14. 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.

  15. Multidisciplinary Care.

    PubMed

    Daly, Megan E; Riess, Jonathan W

    2016-01-01

    Optimal multidisciplinary care of the lung cancer patient at all stages should encompass integration of the key relevant medical specialties, including not only medical, surgical, and radiation oncology, but also pulmonology, interventional and diagnostic radiology, pathology, palliative care, and supportive services such as physical therapy, case management, smoking cessation, and nutrition. Multidisciplinary management starts at staging and tissue diagnosis with pathologic and molecular phenotyping, extends through selection of a treatment modality or modalities, management of treatment and cancer-related symptoms, and to survivorship and end-of-life care. Well-integrated multidisciplinary care may reduce treatment delays, improve cancer-specific outcomes, and enhance quality of life. We address key topics and areas of ongoing investigation in multidisciplinary decision making at each stage of the lung cancer treatment course for early-stage, locally advanced, and metastatic lung cancer patients. PMID:27535399

  16. Computer-automated multi-disciplinary analysis and design optimization of internally cooled turbine blades

    NASA Astrophysics Data System (ADS)

    Martin, Thomas Joseph

    This dissertation presents the theoretical methodology, organizational strategy, conceptual demonstration and validation of a fully automated computer program for the multi-disciplinary analysis, inverse design and optimization of convectively cooled axial gas turbine blades and vanes. Parametric computer models of the three-dimensional cooled turbine blades and vanes were developed, including the automatic generation of discretized computational grids. Several new analysis programs were written and incorporated with existing computational tools to provide computer models of the engine cycle, aero-thermodynamics, heat conduction and thermofluid physics of the internally cooled turbine blades and vanes. A generalized information transfer protocol was developed to provide the automatic mapping of geometric and boundary condition data between the parametric design tool and the numerical analysis programs. A constrained hybrid optimization algorithm controlled the overall operation of the system and guided the multi-disciplinary internal turbine cooling design process towards the objectives and constraints of engine cycle performance, aerodynamic efficiency, cooling effectiveness and turbine blade and vane durability. Several boundary element computer programs were written to solve the steady-state non-linear heat conduction equation inside the internally cooled and thermal barrier-coated turbine blades and vanes. The boundary element method (BEM) did not require grid generation inside the internally cooled turbine blades and vanes, so the parametric model was very robust. Implicit differentiations of the BEM thermal and thereto-elastic analyses were done to compute design sensitivity derivatives faster and more accurately than via explicit finite differencing. A factor of three savings of computer processing time was realized for two-dimensional thermal optimization problems, and a factor of twenty was obtained for three-dimensional thermal optimization problems

  17. 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.

  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 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.

  20. A Systematic Approach for Quantitative Analysis of Multidisciplinary Design Optimization Framework

    NASA Astrophysics Data System (ADS)

    Kim, Sangho; Park, Jungkeun; Lee, Jeong-Oog; Lee, Jae-Woo

    An efficient Multidisciplinary Design and Optimization (MDO) framework for an aerospace engineering system should use and integrate distributed resources such as various analysis codes, optimization codes, Computer Aided Design (CAD) tools, Data Base Management Systems (DBMS), etc. in a heterogeneous environment, and need to provide user-friendly graphical user interfaces. In this paper, we propose a systematic approach for determining a reference MDO framework and for evaluating MDO frameworks. The proposed approach incorporates two well-known methods, Analytic Hierarchy Process (AHP) and Quality Function Deployment (QFD), in order to provide a quantitative analysis of the qualitative criteria of MDO frameworks. Identification and hierarchy of the framework requirements and the corresponding solutions for the reference MDO frameworks, the general one and the aircraft oriented one were carefully investigated. The reference frameworks were also quantitatively identified using AHP and QFD. An assessment of three in-house frameworks was then performed. The results produced clear and useful guidelines for improvement of the in-house MDO frameworks and showed the feasibility of the proposed approach for evaluating an MDO framework without a human interference.

  1. Analysis of the bimodal diurnal rainfall pattern during the summer monsoon over the Hong Kong Archipelago

    SciTech Connect

    Welsh, P.T.; Wai, M.M.K.

    1994-12-31

    A complete year`s record of hourly surface measurements was used to examine the atmospheric diurnal secondary circulations over the Hong Kong Archipelago in conjunction with spatial and temporal variations of surface temperature, wind speed and rainfall. The two objectives in this study are to identify both the spatial and temporal variations of diurnal temperature, wind speed and rainfall over the entire Hong Kong area, and to link these variations to the forcing mechanisms and their scales of action. In this way, the authors can establish some useful understanding of the forcing and response, leading toward a systematic method to identify inappropriate parameterization schemes in otherwise potentially useful numerical models. This study focuses on the occurrence of a summer biomodal rainfall maximum which results from the interaction of summer monsoon flow and local mesoscale secondary circulations. The result is a dominant morning rainfall maximum and a secondary afternoon peak. Evidence of atmospheric diurnal secondary circulations are found at 10 local data stations. Though system strength and timing vary, these secondary circulation systems behave like a classic sea breeze circulation, complicated by superimposed slope effects, but dominated by the summer monsoon flow.

  2. 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.

  3. 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

  4. 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.

  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. Dehydration processes in the Indian monsoon anticyclone : Lagrangian analysis and sensitivity to vertical wind fields.

    NASA Astrophysics Data System (ADS)

    James, R.; Bonazzola, M.; Legras, B.; Surbled, K.; Fueglistaler, S.

    2007-12-01

    During Asian monsoon season, the large-scale monsoon flux generates a persistent anticyclonic circulation at the tropopause over the sub-tropical part of Asia (15°N to 40°N). The anticyclonic region is associated with a large water vapor maxima, which can hardly be explained by the seasonal variation of tropopause temperatures alone. In the upper troposphere, the moistening effect of deep convective events in the anticyclone has been pointed out by Randel and Park (JGR, 10.1029/2005JD006490, 2006). However, at higher levels the deep convective area is separated from the anticyclonic region (Park et al., JGR, 10.1029/2006JD008294, 2007). The large-scale circulation (slow ascent and anticyclonic barrier) seems hence essential to explain the water vapor distribution observed at 100 hPa (MLS/AURA or MIPAS). In this context, the ability of the large-scale wind fields to represent the water vapor distribution has been studied from back-trajectories. The calculations have been performed over three summers (1998, 1999 and 2000) using two representations of the vertical wind in the ERA-40 dataset and the new ERA-Interim: the "classical" wind (from divergence equation) and the diabatic wind (from temperature tendency equation). Coupled to a simple microphysical model, back-trajectories can reconstruct water vapor maps (Fueglistaler et al., JGR, 10.1029/2004JD005516, 2005). Here, the comparison to MLS/AURA retrievements at 100 hPa shows that : if "classical" wind calculations exhibit large discrepancies, diabatic winds accurately reconstruct the location and the concentration of the indian monsoon water vapor maxima without represented small-scale micro-physic. Investigating transport and dehydration processes along trajectories (intersection with isentrops, clouds from CLAUS,...) the Lagrangian approach offers a synthetic scenario. After being quickly lifted by deep convection over the Bay of Bengal until 350-360 K, most of the parcels are freezed-dry around 370 K above

  8. 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

  9. 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

  10. 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

  11. The monsoon experiment MONEX

    NASA Technical Reports Server (NTRS)

    Das, P. K.

    1979-01-01

    The effects of monsoons in different parts of the world on the Earth's atmosphere were studied by MONEX, India's Monsoon Experiment program. Data were gathered from meteorological satellites, sounding rockets, aircraft, land and shipborne stations.

  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. 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.

  14. The City: A Multidisciplinary Unit Exercising the Higher Level Thinking Skills of Analysis, Synthesis, and Evaluation.

    ERIC Educational Resources Information Center

    Burger, Celia R.

    Designed for use with sixth grade students, this multidisciplinary unit combines independent study of urban areas with activities to develop students' higher level thinking skills. Following suggestions to teachers on strategies for introducing the unit, four options for independent study are described. The first is a study of a topic related to…

  15. 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.

  16. 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.

  17. 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.

  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. 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.

  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. Isentropic analysis of the Indian Summer Monsoon circulation and its implications for the active and break periods

    NASA Astrophysics Data System (ADS)

    Pauluis, O. M.; Sandeep, S.; Ravindran, A. M.

    2014-12-01

    The atmospheric flow during the Indian Summer Monsoon here is analyzed in isentropic coordinates in two different ways. First, the lateral mass transport fo air is separated in terms of both the potential temperature and equivalent potential temperature. This approach, originally developed to analyze the global meridional circulation, makes it possible to identify the thermodynamic properties of the inflow and outflow. It is shown here how the properties of various air masses, such as the inflow of warm moist air in the boundary layer, upper tropospheric outflow, and midlatitudes dry air intrusion, can be systematically identified. Second, we analyze the vertical overturning in terms of terms of the equivalent potential temperature of the ascending and subsiding air parcels over the indian subcontinent, which allows us to further infer the thermodynamic transformation occurring during the monsoon. This technique is first used to look at the evolution of the flow through the seasonal cycle. We then further analyze the circulation patterns associated with monsoon breaks and active periods. In doing so, we identify midtropospheric in usions of dry air from the midlatitudes as a key precursor of monsoon breaks. The meteorological conditions associated for such intrusion to reach the subcontinent are then discussed.

  2. 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.

  3. 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.

  4. A multi-disciplinary plan for easier access, management, and analysis of science data

    NASA Astrophysics Data System (ADS)

    Hornstein, Rhoda Shaller; Miller, Raymond E.; Hei, Donald J.; Kaufmann, David E.; LoPinto, Frank J.; Todd, Jacqueline E.

    NASA's COST LESS Team is pursuing strategies to reduce the cost and complexity of planning and executing space missions. The team's technical goal is to reverse the trend of constructing unique solutions for similar problems. To this end, the team is exploring ways to represent mission functionality in terms of building blocks and is discovering approaches that could accommodate the same building blocks for seemingly disparate activities, such as organizing processed telemetry data, controlling onboard experiments, searching science archives, reducing and presenting information to science users, and supporting educational outreach. Reusable object technology (UOT), a research undertaking by the authors, is showing promise in recognizing similarities in functions which were previously viewed as unique because they appeared in different programs or mission phases. Since UOT is aimed at being implementation independent (i.e. the function performed could be accomplished manually, by an automated process, by a specialized instrument, etc.), no premature judgment for automation or autonomy need be made. In this paper, the authors attempt to strike a balance between theory and reality as they describe UOT, including its beginnings, its underpinning, its utility, and its potential for achieving substantive reductions in cost and complexity for the Agency's space programs. The authors discuss their collaboration with the Center for EUV Astrophysics, University of California, Berkeley to reduce the cost and complexity of science investigations. Their multi-disciplinary plan incorporates both UOT and a complementary technology introduced in this paper, called interactive archives.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. GIS Tool for Real-time Decision Making and Analysis of Multidisciplinary Cryosphere Datasets.

    NASA Astrophysics Data System (ADS)

    Roberts, S. D.; Moore, J. A.

    2004-12-01

    In support of the Western Arctic Shelf-Basin Interaction Project(SBI) a web-based interactive mapping server was installed on the USCGC Healy's on-board science computer network during its 2004 spring(HLY-04-02) and summer cruises (HLY-04-03) in the Chukchi and Beaufort Seas. SBI is a National Science Foundation sponsored multi-year and multidisciplinary project studying the biological productivity in the region. The mapping server was developed by the UCAR Joint Office of Science Support(JOSS) using OpenSource GIS tools(University of Minnesota Mapserver and USGS MapSurfer). Additional OpenSource tools such as GMT and MB-Systems were also utilized. The key layers in this system are the current ship track, station locations, multibeam bottom bathymetry, IBCAO bathymetry, DMSP satellite imagery , NOAA AVHRR Sea Surface temperature and all past SBI Project ship tracks and station locations. The ship track and multibeam layers are updated in real-time and the satellite layers are updated daily only during clear weather. In addition to using current high resolution multibeam bathymetry data, a composite high resolution bathymetry layer was created using multibeam data from past cruises in the SBI region. The server provides click-and-drag zooms, pan, feature query, distance measure and lat/lon/depth querys on a polar projection map of the arctic ocean. The main use of the system on the ship was for cruise track and station position planning by the scientists utilizing all available historical data and high resolution bathymetry. It was also the main source of information to all the scientist on board as to the cruise progress and plans. The system permitted on-board scientists to integrate historical cruise information for comparative purposes. A mirror web site was set up on land and the current ship track/station information was copied once a day to this site via a satellite link so people interested SBI research could follow the cruise progress.

  10. Trends in global monsoon area and precipitation over the past 30 years

    NASA Astrophysics Data System (ADS)

    Hsu, Pang-chi; Li, Tim; Wang, Bin

    2011-04-01

    The analysis of the GPCP and CMAP datasets during the past 30 years (1979-2008) indicates that there are consistent increasing trends in both the global monsoon area (GMA) and the global monsoon total precipitation (GMP). This positive monsoon rainfall trend differs from previous studies that assumed a fixed global monsoon domain. Due to the increasing trends in both the GMA and GMP, a global monsoon intensity (GMI) index, which measures the global monsoon precipitation amount per unit area, is introduced. The GMI measures the strength of the global monsoon. Our calculations with both the GPCP and CMAP datasets show a consistent downward trend in the GMI over the past 30 years. This decreasing trend is primarily attributed to a greater percentage increase in the GMA than in the GMP. A further diagnosis reveals that the decrease of the GMI is primarily attributed to the land monsoon in the GPCP, but to the oceanic monsoon in the CMAP.

  11. 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

    2014-01-01

    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.

  12. A program to form a multidisciplinary data base and analysis for dynamic systems

    NASA Technical Reports Server (NTRS)

    Taylor, L. W.; Suit, W. T.; Mayo, M. H.

    1984-01-01

    Diverse sets of experimental data and analysis programs have been assembled for the purpose of facilitating research in systems identification, parameter estimation and state estimation techniques. The data base analysis programs are organized to make it easy to compare alternative approaches. Additional data and alternative forms of analysis will be included as they become available.

  13. 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.

  14. Energetics and monsoon bifurcations

    NASA Astrophysics Data System (ADS)

    Seshadri, Ashwin K.

    2016-04-01

    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.

  15. Monsoon abrupt change and its dominant factors

    NASA Astrophysics Data System (ADS)

    Yao, Qiang; Fu, Conbin

    2010-05-01

    Abrupt changes of monsoon are apparent in the geological record of climate over various timescales. During Holocene and last glacial period, rainfall in India and China has undergone strong and abrupt changes. In this context, we regard monsoon as dissipative system, which has many characteristic times, to contrive various factors and corresponding mechanism dominated in monsoon's abrupt change. The abrupt change of monsoon over inter-decadal to century timescales may be resulting from different fluctuation's competition, which impose on the inner basic physic processes. In order to find out the key factors which control the monsoon's abrupt change, starting from the seminar works by Leith, who proposed to employ the Fluctuation-dissipation Response theory(FDR) to study the response of climatic systems to changes in the external forcing, many authors applied this relation to different geophysical problems, ranging from simplified models to general circulation models and to the covariance of satellite radiance spectra. The FDR has been originally developed in the framework of statistical mechanics of Hamiltonian systems, nevertheless a generalized FDR holds under rather general hypotheses, regardless of the Hamiltonian, or equilibrium nature of the system. Our work verify the FDR theory' applicability in monsoon systems, which demonstrates that it can reveal clear and fundamental factors that control monsoon's abrupt change. By making use of FDR theory, combined with observational data analysis, we have already seen how monsoon systems with many characteristics times, different correlation functions behave differently and a variety of timescales emerges, which correspond to the different decay times of the correlation functions. Via theoretical and data analysis, it is suggested that each monsoon system has experienced several significant abrupt changes in 20th century. The global main monsoon rainfall has undergone an obvious abrupt jump in the mid- and late 1970s

  16. Understanding Dry Bias in the Simulations of Indian Monsoon by CFSv2 Through Analysis of Moisture Transport

    NASA Astrophysics Data System (ADS)

    Saheer, Sahana; Pathak, Amey; Mathew, Roxy; Ghosh, Subimal

    2016-04-01

    Simulations of Indian Summer Monsoon (ISM) with its seasonal and subseasonal characteristics is highly crucial for predictions/ projections towards sustainable agricultural planning and water resources management. The Climate forecast system version 2 (CFSv2), the state of the art coupled climate model developed by National Center for Environmental Prediction (NCEP), is evaluated here for the simulations of ISM. Even though CFSv2 is a fully coupled ocean-atmosphere-land model with advanced physics, increased resolution and refined initialization, its ISM simulations/ predictions/ projections, in terms of seasonal mean and variability are not satisfactory. Numerous works have been done for verifying the CFSv2 forecasts in terms of the seasonal mean, its mean and variability, active and break spells, and El Nino Southern Oscillation (ENSO)-monsoon interactions. Underestimation of JJAS precipitation over the Indian land mass is one of the major drawbacks of CFSv2. ISM gets the moisture required to maintain the precipitation from different oceanic and land sources. In this work, we find the fraction of moisture supplied by different sources in the CFSv2 simulations and the findings are compared with observed fractions. We also investigate the possible variations in the moisture contributions from these different sources. We suspect that the deviation in the relative moisture contribution from different sources to various sinks over the monsoon region has resulted in the observed dry bias. We also find that over the Arabian Sea region, which is the key moisture source of ISM, there is a premature built up of specific humidity during the month of May and a decline during the later months of JJAS. This is also one of the reasons for the underestimation of JJAS mean precipitation.

  17. Spatial and Temporal Variations in Indian Summer Monsoon Rainfall and Temperature: An Analysis Based on RegCM3 Simulations

    NASA Astrophysics Data System (ADS)

    Dash, S. K.; Mamgain, Ashu; Pattnayak, K. C.; Giorgi, F.

    2013-04-01

    Regional climate models are important tools to examine the spatial and temporal characteristics of rainfall and temperature at high resolutions. Such information has potential applications in sectors like agriculture and health. In this study, the Regional Climate Model Version 3 (RegCM3) has been integrated in the ensemble mode at 55 km resolution over India for the summer monsoon season during the years 1982-2009. Emphasis has been given on the validation of the model simulation at the regional level. In Central India, both rainfall and temperature show the best correlations with respective observed values. The model gives rise to large wet biases over Northwest and Peninsular India. RegCM3 slightly underestimates the summer monsoon precipitation over the Central and Northeast India. Nevertheless, over these regions, RegCM3 simulated rainfall is closer to the observations when compared to the other regions where rainfall is overestimated. The position of the monsoon trough simulated by the model lies to the north of its original observed position. This is similar to the usual monsoon break conditions leading to less rainfall over Central India. RegCM3 simulated surface maximum temperature shows a large negative bias over the country while the surface minimum temperature is close to the observation. Nevertheless, there is a strong correlation between the all India weighted average surface temperature simulated by RegCM3 and IMD observed values. While examining the extreme weather conditions in Central India, it is found that RegCM3 simulated frequencies of occurrence of very wet days, extremely wet days, warm days and warm nights more often as compared to those in IMD observed values. However, these are systematic biases. The model biases in the frequencies of distribution of rainfall extremes explain the wet and dry biases in different regions in the country. Overall, the inter-annual characteristics of both the rainfall and temperature extremes simulated by Reg

  18. 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.

  19. 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.

  20. A comparison of regional monsoon variability using monsoon indices

    NASA Astrophysics Data System (ADS)

    Yim, So-Young; Wang, Bin; Liu, Jian; Wu, Zhiwei

    2014-09-01

    The present study aims to (a) examine meteorological basis for construction of regional monsoon indices and (b) explore the commonality and differences among tropical regional monsoons, especially the teleconnection and monsoon-ENSO relationship. We show that the area-averaged summer precipitation intensity is generally a meaningful precipitation index for tropical monsoons because it represents very well both the amplitude of annual cycle and the leading mode of year-to-year rainfall variability with a nearly uniform spatial pattern. The regional monsoon circulation indices can be defined in a unified way (measuring monsoon trough vorticity) for seven tropical monsoon regions, viz.: Indian, Australian, western North Pacific, North and South American, and Northern and Southern African monsoons. The structures of the tropical monsoons are commonly characterized by a pair of upper-level double anticyclones residing in the subtropics of both hemispheres; notably the winter hemispheric anticyclone has a barotropic structure and is a passive response. Two types of upper-level teleconnection patterns are identified. One is a zonal wave train emanating from the double anticyclones downstream along the westerly jets in both hemispheres, including Indian, Northern African and Australian monsoons; the other is a meridional wave train emanating from the double anticyclones polewards, such as the South American and western North Pacific monsoons. Over the past 55 years all regional summer monsoons have non-stationary relationship with ENSO except the Australian monsoon. The regional monsoon-ENSO relationship is found to have common changing points in 1970s. The relationships were enhanced for the western North Pacific, Northern African, North American and South American summer monsoons, but weakened for the Indian summer monsoon (with a recovery in late 1990s). Regardless the large regional differences, the monsoon precipitations over land areas of all tropical monsoon regions

  1. The genome clinic: a multidisciplinary approach to assessing the opportunities and challenges of integrating genomic analysis into clinical care.

    PubMed

    Bowdin, Sarah; Ray, Peter N; Cohn, Ronald D; Meyn, M Stephen

    2014-05-01

    Our increasing knowledge of how genomic variants affect human health and the falling costs of whole-genome sequencing are driving the development of individualized genetic medicine. This new clinical paradigm uses knowledge of an individual's genomic variants to guide health care decisions throughout life, to anticipate, diagnose, and manage disease. While individualized genetic medicine offers the promise of transformative change in health care, it forces us to reconsider existing ethical, scientific, and clinical paradigms. The potential benefits of presymptomatic identification of at risk individuals, improved diagnostics, individualized therapy, accurate prognosis, and avoidance of adverse drug reactions coexist with the potential risks of uninterpretable results, psychological harm, outmoded counseling models, and increased health care costs. Here, we review the challenges of integrating genomic analysis into clinical practice and describe a prototype for implementing genetic medicine. Our multidisciplinary team of bioinformaticians, health economists, ethicists, geneticists, genetic counselors, and clinicians has designed a "Genome Clinic" research project that addresses multiple challenges in genomic medicine-ranging from the development of bioinformatics tools for the clinical assessment of genomic variants and the discovery of disease genes to health policy inquiries, assessment of clinical care models, patient preference, and the ethics of consent.

  2. 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.

  3. 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.

  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. 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.

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Seismic observations and multidisciplinary interpretation of their analysis: understanding the unrest at Turrialba volcano (Costa Rica)

    NASA Astrophysics Data System (ADS)

    Martini, F.; Ovsicori-Una Volcano Monitoring Group

    2009-04-01

    significant interference on troposphere O3 measurements at 2-3 km altitude ~50 km W from the volcano, detected by the Ozone Monitoring Instrument (OMI) on NASA's EOS-Aura satellite. The current geodetic network at Turrialba volcano (comprising two small EDM networks, leveling lines, an electronic tiltmeter and periodical GPS campaigns) measuring during the reawakening of the volcano for the past decade, is very limited but it has detected an inflationary trend in the crater area in the last 2 years. The 2007 peak in seismic activity has marked an important change in the seismicity patterns as well as in the geochemical, geodetical and field observations. Previous to it, VT type events have been mainly recorded, typically showing a spindle shape waveform most likely due to the strongly scattering volcanic environment. Since late 2007, gas-driven deep impulsive events have dominated the seismicity, often followed by episodes of harmonic tremor. In this work, we present a summary of the activity of the volcano and the data collected during more than 10 years of monitoring, with particular emphasis on the changes occurred over the last 2 years. We show results from analysis of the seismic data collected by the seismic permanent network and by a small aperture short-period seismic array deployed in 2008, as well as the initial observations recorded by several broad-band arrays due to be deployed at the end of January 2009. Integrating the geochemistry, geophysical, geodetical, and field data available, we present an interpretation of the seismic observations and the current status of the volcano.

  13. A multidisciplinary geomatics approach to morphometric and morphotectonic analysis of the Cannobino Basin (Piemonte Region, NW-Italy).

    NASA Astrophysics Data System (ADS)

    Bacenetti, Marco; Ghiraldi, Luca; Giardino, Marco

    2014-05-01

    The paper presents an integrated multidisciplinary approach to the morphometric and morphotectonic characterization of the Cannobino Basin (Piemonte Region, NW-Italy). The basin is drained by the Cannobino river; in its first 8 km, it flows SE to NW along a wide valley characterized by glacial landforms; thereafter it suddenly turns South assuming a W to E direction, by flowing in a deeply entrenched valley to the intermontane basin of the Maggiore Lake. This area belongs to the Lepontine Alps, which from the geological point of view belong to the Southern Alps. His Hercynian basement is divided in two units: Ivrea-Verbano Zone (IVZ) and Serie dei Laghi (SDL). The IVZ outcrops in the northern sector of the basin, while the SDL outcrops in the southern and central sector. They separated by the Cossato-Mergozzo-Brissago (CMB) and Pogallo lines (PL). These major discontinuities and the neoctonic activity of their shear zones possibly control Quaternary evolution of the alpine relief. Detailed studies of the area are needed for understanding possible interactions of neotectonic activity, fluvial/glacial erosional/depositional processes and slope dynamics. Our focus is on drainage basin characteristics and its evolutionary stages in response to local and regional base level changes and to differential rock uplift. GIS methodologies combined with DEMs analyses are among the most common geomatics approaches to geomorphology. Based on this framework, an evaluation of the geomorphometric characteristic of the Cannobino Basin has been carried out by using an aerial LIDAR DEM (5x5 meters, Regione Piemonte, 2009). The workflow followed for calculating the geomorphic indexes can be summarized in different steps: i) drainage network extraction and hierarchization; ii) lineament features digitalization and interpretation; iii) azimuthal distribution of drainage pattern; iv) DEM analysis and evaluation of linear, areal indexes and SWAT profile. The multidisciplinary and innovative

  14. Reconciling societal and scientific definitions for the monsoon

    NASA Astrophysics Data System (ADS)

    Reeve, Mathew; Stephenson, David

    2014-05-01

    Science defines the monsoon in numerous ways. We can apply these definitions to forecast data, reanalysis data, observations, GCMs and more. In a basic research setting, we hope that this work will advance science and our understanding of the monsoon system. In an applied research setting, we often hope that this work will benefit a specific stakeholder or community. We may want to inform a stakeholder when the monsoon starts, now and in the future. However, what happens if the stakeholders cannot relate to the information because their perceptions do not align with the monsoon definition we use in our analysis? We can resolve this either by teaching the stakeholders or learning from them about how they define the monsoon and when they perceive it to begin. In this work we reconcile different scientific monsoon definitions with the perceptions of agricultural communities in Bangladesh. We have developed a statistical technique that rates different scientific definitions against the people's perceptions of when the monsoon starts and ends. We construct a probability mass function (pmf) around each of the respondent's answers in a questionnaire survey. We can use this pmf to analyze the time series of monsoon onsets and withdrawals from the different scientific definitions. We can thereby quantitatively judge which definition may be most appropriate for a specific applied research setting.

  15. Multivariate and Descriptive Discriminant Analysis of Multidisciplinary Approaches to Integrating Mathematics, Science, and Technology Education in the High School.

    ERIC Educational Resources Information Center

    Wicklein, Robert C.; Schell, John W.

    A study examined the perceptions of participants in a multidisciplinary project regarding the degree to which the integration of technology, mathematics, and science had enabled advanced mental skills in technical thinking and problem solving. A literature review focused on advanced learning and thinking, ill-structured workplace problems,…

  16. Matched Pair Analysis of Race or Ethnicity in Outcomes of Head and Neck Cancer Patients Receiving Similar Multidisciplinary Care

    PubMed Central

    Chen, Leon M.; Li, Guojun; Reitzel, Lorraine R.; Pytynia, Kristen B.; Zafereo, Mark E.; Wei, Qingyi; Sturgis, Erich M.

    2009-01-01

    It is unknown whether population-level racial or ethnic disparities in mortality from squamous cell carcinoma of the head and neck (SCCHN) also occur in the setting of standardized multidisciplinary-team directed care. Therefore, we conducted a matched-pair study that controlled for several potentially confounding prognostic variables to assess whether a difference in survival exists for African-American or Hispanic-American compared with non-Hispanic white American SCCHN patients receiving similar care. Matched pairs were 81 African-American case and 81 non-Hispanic white control patients and 100 Hispanic-American cases and 100 matched non-Hispanic white controls selected from 1833 patients of a prospective epidemiologic study of incident SCCHN within a single, large multidisciplinary cancer center. Matching variables included age (± 10 years), sex, smoking status (never versus ever), site, tumor stage (T1–2 versus T3–4), nodal status (negative versus positive), and treatment. Cases and controls were not significantly different in proportions of comorbidity score, alcohol use, subsite distribution, overall stage, or tumor grade. Matched-pair and log-rank analyses showed no significant differences between cases and controls in recurrence-free, disease-specific, or overall survival. Site-specific analyses suggested that more-aggressive oropharyngeal cancers occurred more frequently in minority than non-Hispanic white patients. We conclude that minority and non-Hispanic white SCCHN patients receiving similar multidisciplinary-team directed care at a tertiary cancer center have similar survival results overall. These results encourage reducing health disparities in SCCHN through public-health efforts to improve access to multidisciplinary oncologic care (and to preventive measures) and through individual clinician efforts to make the best multidisciplinary cancer treatment choices available for their minority patients. The subgroup finding suggests a biologically

  17. 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.

  18. Pre-monsoon/monsoon thunderstorm characteristics over Pune—An investigation using Doppler Sodar observations

    NASA Astrophysics Data System (ADS)

    Murthy, B. S.; Latha, R.; Sreeja, P.; Kalapureddy, M. C. R.; Dharmaraj, T.; Waghmare, R. T.

    2011-10-01

    Doppler sodar observations of three dimensional (3D) wind fields and thermal structure of convective boundary layer (CBL) on a few thunderstorm days of 2009 during pre-monsoon (May and June; June due to delayed arrival of monsoon over Pune) and monsoon (July and August) are analyzed. They reveal the typical signatures of wind fields for the late afternoon thunderstorm (TS) such as deceleration of winds with or without change in direction leading to convergence a few minutes (˜15-30 min) prior to the onset of TS. Pre-monsoon TS are characterized by broad updrafts and narrow downdrafts in CBL in contrast to the narrow updrafts and broad downdrafts of a normal day (i.e. No-TS day). Mean vertical velocity averaged over CBL period shows net updraft on TS days and net downdraft on No-TS day for the pre-monsoon cases. Similarly calm winds are observed in the CBL on TS-days that support enhanced free convection. During the monsoon period updrafts are observed on both TS and No-TS days with higher values on TS days in comparison, due to the dominance of large-scale monsoon flow over local convection. Relatively higher turbulence kinetic energy (TKE) in CBL is observed on all TS days. Analysis shows that TKE maximum for the day is attained about 1.5-2.0 h prior to the onset of afternoon TS. Mixed-layer depth, determined from TKE profile, is higher than lifting condensation level (LCL) on TS days in May and June indicating saturation of air parcels in updrafts.

  19. 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.

  20. 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.

  1. 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.

  2. Managing Complexity in Multidisciplinary Visualization

    NASA Technical Reports Server (NTRS)

    Miceli, Kristina D.; Lasinski, T. A. (Technical Monitor)

    1995-01-01

    As high performance computing technology progresses, computational simulations are becoming more advanced in their capabilities. In the computational aerosciences domain, single discipline steady-state simulations computed on a single grid are far from the state-of-the-art. In their place are complex, time-dependent multidisciplinary simulations that attempt to model a given geometry more realistically. The product of these multidisciplinary simulations is a massive amount of data stored in different formats, grid topologies, units of measure, etc., as a result of the differences in the simulated physical domains. In addition to the challenges posed by setting up and performing the simulation, additional challenges exist in analyzing computational results. Visualization plays an important role in the advancement of multidisciplinary simulations. To date, visualization has been used to aid in the interpretation of large amounts of simulation data. Because the human visual system is effective in digesting a large amount of information presented graphically, visualization has helped simulation scientists to understand complex simulation results. As these simulations become even more complex, integrating several different physical domains, visualization will be critical to digest the massive amount of information. Another important role for visualization is to provide a common communication medium from which the domain scientists can use to develop, debug, and analyze their work. Multidisciplinary analyses are the next step in simulation technology, not only in computational aerosciences, but in many other areas such as global climate modeling. Visualization researchers must understand and work towards the challenges posed by multidisciplinary simulation scenarios. This paper addresses some of these challenges, describing technologies that must be investigated to create a useful visualization analysis tool for domain scientists.

  3. 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).

  4. 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.

  5. 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.

  6. Observational and modeling studies of impacts of the South China Sea monsoon on the monsoon rainfall in the middle-lower reaches of the Yangtze River during summer

    NASA Astrophysics Data System (ADS)

    Jin, Lijun; Zhao, Ping

    2012-04-01

    Based on the ERA-40 and NCEP/NCAR reanalysis data, the NOAA Climate Prediction Center's merged analysis of precipitation (CMAP), and the fifth-generation PSU/NCAR Mesoscale Model version 3 (MM5v3), we defined a monsoon intensity index over the East Asian tropical region and analyzed the impacts of summer (June-July) South China Sea (SCS) monsoon anomaly on monsoon precipitation over the middle-lower reaches of the Yangtze River (MLRYR) using both observational data analysis and numerical simulation methods. The results from the data analysis show that the interannual variations of the tropical monsoon over the SCS are negatively correlated with the southwesterly winds and precipitation over the MLRYR during June-July. Corresponding to stronger (weaker) tropical monsoon and precipitation, the southwesterly winds are weaker (stronger) over the MLRYR, with less (more) local precipitation. The simulation results further exhibit that when changing the SCS monsoon intensity, there are significant variations of monsoon and precipitation over the MLRYR. The simulated anomalies generally consist with the observations, which verifies the impact of the tropical monsoon on the monsoon precipitation over the MLRYR. This impact might be supported by certain physical processes. Moreover, when the tropical summer monsoon is stronger, the tropical anomalous westerly winds and positive precipitation anomalies usually maintain in the tropics and do not move northward into the MLRYR, hence the transport of water vapor toward southern China is weakened and the southwest flow and precipitation over southern China are also attenuated. On the other hand, the strengthened tropical monsoon may result in the weakening and southward shift of the western Pacific subtropical high through self-adjustment of the atmospheric circulation, leading to the weakening of the monsoon flows and precipitation over the MLRYR.

  7. Eocene precipitation: a global monsoon?

    NASA Astrophysics Data System (ADS)

    Greenwood, D. R.; Huber, M.

    2011-12-01

    The Eocene was the warmest part of the Cenozoic, with warm climates extending across all continents including Antarctica, and extending into the Arctic. Substantive paleobotanical evidence (leaf floras and palynofloras) has demonstrated the existence of broadleaf and coniferous polar forests - a circumpolar rain forest - at both poles. North and South America, Australia, and China in the Eocene were well-forested and humid continents, in contrast to today where 2/3 of these continental areas are arid or semi-arid and lack forests. Each of these regions reflect past climate states - mesothermal moist climates with low thermal seasonality at high latitudes - that have no analog in the modern world. Recent modelling and paleontological proxy data, however, is revealing a high degree of seasonality to precipitation for these continental areas, indicating a monsoon-type precipitation regime may have characterized Eocene 'greenhouse climates'. Paleobotanical proxies offer 2 methods for estimated paleo-precipitation; leaf physiognomy (including both CLAMP and leaf area analysis), and quantitative analysis of nearest living relatives ('NLRs') of macrofloras. Presented here are 1) an updated leaf area analysis calibration with smaller errors of the estimate than previously provided, and 2) analyses of fossil floras from North America, Canada, the Arctic, and Australia. Analysis of the Canadian floras indicate moist climates (MAP >100cm/a) in the early and middle Eocene at middle and high paleolatitudes. Precipitation for western North America at mid-latitudes is also estimated as high, but a seasonally dry interior and south-east is indicated. For Australia, precipitation in the south-east is estimated >120 cm/a, but the macrofloras indicate a drier interior (MAP ~60 cm/a) and seasonal drought, contradicting estimates of ~120 cm/a based on NLR analysis of pollen floras. Recently published data show that north-eastern China in the Eocene had a monsoonal-type seasonality for

  8. Pacific freshening drives Pliocene cooling and Asian monsoon intensification

    PubMed Central

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

    2014-01-01

    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. PMID:24969361

  9. Early warnings and missed alarms for abrupt monsoon transitions

    NASA Astrophysics Data System (ADS)

    Thomas, Z. A.; Kwasniok, F.; Boulton, C. A.; Cox, P. M.; Jones, R. T.; Lenton, T. M.; Turney, C. S. M.

    2015-12-01

    Palaeo-records from China demonstrate that the East Asian Summer Monsoon (EASM) is dominated by abrupt and large magnitude monsoon shifts on millennial timescales, switching between periods of high and weak monsoon rains. It has been hypothesized that over these timescales, the EASM exhibits two stable states with bifurcation-type tipping points between them. Here we test this hypothesis by looking for early warning signals of past bifurcations in speleothem δ18O records from Sanbao Cave and Hulu Cave, China, spanning the penultimate glacial cycle. We find that although there are increases in both autocorrelation and variance preceding some of the monsoon transitions during this period, it is only immediately prior to the abrupt monsoon shift at the penultimate deglaciation (Termination II) that statistically significant increases are detected. To supplement our data analysis, we produce and analyse multiple model simulations that we derive from these data. We find hysteresis behaviour in our model simulations with transitions directly forced by solar insolation. However, signals of critical slowing down, which occur on the approach to a bifurcation, are only detectable in the model simulations when the change in system stability is sufficiently slow to be detected by the sampling resolution of the data set. This raises the possibility that the early warning "alarms" were missed in the speleothem data over the period 224-150 kyr and it was only at the monsoon termination that the change in the system stability was sufficiently slow to detect early warning signals.

  10. 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.

  11. 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

  12. Spatiotemporal variability of rainfall extremes in monsoonal climates - examples from the South American Monsoon and the Indian Monsoon Systems (Invited)

    NASA Astrophysics Data System (ADS)

    Bookhagen, B.; Boers, N.; Marwan, N.; Malik, N.; Kurths, J.

    2013-12-01

    Monsoonal rainfall is the crucial component for more than half of the world's population. Runoff associated with monsoon systems provide water resources for agriculture, hydropower, drinking-water generation, recreation, and social well-being and are thus a fundamental part of human society. However, monsoon systems are highly stochastic and show large variability on various timescales. Here, we use various rainfall datasets to characterize spatiotemporal rainfall patterns using traditional as well as new approaches emphasizing nonlinear spatial correlations from a complex networks perspective. Our analyses focus on the South American (SAMS) and Indian (ISM) Monsoon Systems on the basis of Tropical Rainfall Measurement Mission (TRMM) using precipitation radar and passive-microwave products with horizontal spatial resolutions of ~5x5 km^2 (products 2A25, 2B31) and 25x25 km^2 (3B42) and interpolated rainfall-gauge data for the ISM (APHRODITE, 25x25 km^2). The eastern slopes of the Andes of South America and the southern front of the Himalaya are characterized by significant orographic barriers that intersect with the moisture-bearing, monsoonal wind systems. We demonstrate that topography exerts a first-order control on peak rainfall amounts on annual timescales in both mountain belts. Flooding in the downstream regions is dominantly caused by heavy rainfall storms that propagate deep into the mountain range and reach regions that are arid and without vegetation cover promoting rapid runoff. These storms exert a significantly different spatial distribution than average-rainfall conditions and assessing their recurrence intervals and prediction is key in understanding flooding for these regions. An analysis of extreme-value distributions of our high-spatial resolution data reveal that semi-arid areas are characterized by low-frequency/high-magnitude events (i.e., are characterized by a ';heavy tail' distribution), whereas regions with high mean annual rainfall have a

  13. Global Monsoon Dynamics and Climate Change

    NASA Astrophysics Data System (ADS)

    Zhisheng, An; Guoxiong, Wu; Jianping, Li; Youbin, Sun; Yimin, Liu; Weijian, Zhou; Yanjun, Cai; Anmin, Duan; Li, Li; Jiangyu, Mao; Hai, Cheng; Zhengguo, Shi; Liangcheng, Tan; Hong, Yan; Hong, Ao; Hong, Chang; Juan, Feng

    2015-05-01

    This article provides a comprehensive review of the global monsoon that encompasses findings from studies of both modern monsoons and paleomonsoons. We introduce a definition for the global monsoon that incorporates its three-dimensional distribution and ultimate causes, emphasizing the direct drive of seasonal pressure system changes on monsoon circulation and depicting the intensity in terms of both circulation and precipitation. We explore the global monsoon climate changes across a wide range of timescales from tectonic to intraseasonal. Common features of the global monsoon are global homogeneity, regional diversity, seasonality, quasi-periodicity, irregularity, instability, and asynchroneity. We emphasize the importance of solar insolation, Earth orbital parameters, underlying surface properties, and land-air-sea interactions for global monsoon dynamics. We discuss the primary driving force of monsoon variability on each timescale and the relationships among dynamics on multiple timescales. Natural processes and anthropogenic impacts are of great significance to the understanding of future global monsoon behavior.

  14. Tohono O'odham Monsoon Climatology

    NASA Astrophysics Data System (ADS)

    Ackerman, G.

    2006-12-01

    The North American monsoon is a summertime weather phenomenon that develops over the southwestern North America. For thousands of years the Tohono O'odham people of this area have depended on the associated rainy season (Jukiabig Masad) to grow traditional crops using runoff agriculture. Today, the high incidence of Type II diabetes among native people has prompted many to return to their traditional agricultural diets. Local monsoon onset dates and the North American Regional Reanalysis dataset were used to develop a 24-year Tohono O'odham Nation (TON) monsoon and pre-monsoon climatology that can be used as a tool for planning runoff agriculture. Using monsoon composite datasets, temporal and spatial correlations between antecedent period meteorological variables, monsoon onset dates and total monsoon precipitation were examined to identify variables that could be useful in predicting the onset and intensity of the monsoon. The results suggest additional research is needed to identify variables related to monsoon onset and intensity.

  15. Multidisciplinary management of complex care.

    PubMed

    Schofield, Deborah; Fuller, Jeffrey; Wagner, Scott; Friis, Leanne; Tyrell, Bill

    2009-02-01

    Rural and remote areas of Australia are facing serious health workforce shortages. Multidisciplinary teams are one way of making the most of the rural workforce. In this paper, the advantages of multidisciplinary care in terms of patient outcomes, clinician satisfaction and system efficiency are considered with reference to an innovative rural multidisciplinary model that highlights how these positive outcomes can be achieved. Ways of developing the capacity of the future workforce for work in multidisciplinary teams are discussed.

  16. Multidisciplinary computational aerosciences

    NASA Technical Reports Server (NTRS)

    Kutler, Paul

    1992-01-01

    As the challenges of single disciplinary computational physics are met, such as computational fluid dynamics, computational structural mechanics, computational propulsion, computational aeroacoustics, computational electromagnetics, etc., scientists have begun investigating the combination of these single disciplines into what is being called multidisciplinary computational aerosciences (MCAS). The combination of several disciplines not only offers simulation realism but also formidable computational challenges. The solution of such problems will require computers orders of magnitude larger than those currently available. Such computer power can only be supplied by massively parallel machines because of the current speed-of-light limitation of conventional serial systems. Even with such machines, MCAS problems will require hundreds of hours for their solution. To efficiently utilize such a machine, research is required in three areas that include parallel architectures, systems software, and applications software. The main emphasis of this paper is the applications software element. Examples that demonstrate application software for multidisciplinary problems currently being solved at NASA Ames Research Center are presented. Pacing items for MCAS are discussed such as solution methodology, physical modeling, computer power, and multidisciplinary validation experiments.

  17. 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.

  18. 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.

  19. 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.

  20. The use of fractional accumulated precipitation for the evaluation of the annual cycle of monsoons

    NASA Astrophysics Data System (ADS)

    Sperber, Kenneth R.; Annamalai, H.

    2014-12-01

    Using pentad rainfall data we demonstrate the benefits of using accumulated rainfall and fractional accumulated rainfall for the evaluation of the annual cycle of rainfall over various monsoon domains. Our approach circumvents issues related to using threshold-based analysis techniques for investigating the life-cycle of monsoon rainfall. In the Coupled Model Intercomparison Project-5 models we find systematic errors in the phase of the annual cycle of rainfall. The models are delayed in the onset of summer rainfall over India, the Gulf of Guinea, and the South American Monsoon, with early onset prevalent for the Sahel and the North American Monsoon. This, in combination with the rapid fractional accumulation rate, impacts the ability of the models to simulate the fractional accumulation observed during summer. The rapid fractional accumulation rate and the time at which the accumulation begins are metrics that indicate how well the models concentrate the monsoon rainfall over the peak rainfall season, and the extent to which there is a phase error in the annual cycle. The lack of consistency in the phase error across all domains suggests that a "global" approach to the study of monsoons may not be sufficient to rectify the regional differences. Rather, regional process studies are necessary for diagnosing the underlying causes of the regionally-specific systematic model biases over the different monsoon domains. Despite the afore-mentioned biases, most models simulate well the interannual variability in the date of monsoon onset, the exceptions being models with the most pronounced dry biases. Two methods for estimating monsoon duration are presented, one of which includes nonlinear aspects of the fractional accumulation. The summer fractional accumulation of rainfall provides an objective way to estimate the extent of the monsoon domain, even in models with substantial dry biases for which monsoon is not defined using threshold-based techniques.

  1. 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

  2. [Chagas disease in a non endemic country: a study in the district of Bologna (Italy). Multidisciplinary analysis of the disease in the Latin American migrant population].

    PubMed

    Di Girolamo, C; Marta, B L; Ciannameo, A; Cacciatore, F; Balestra, G L; Bodini, C; Taroni, F

    2010-01-01

    Chagas disease is a parasitic illness endemic in 21 countries of Central and South America, affecting over 10 million people. Due to the increase of migration flows to Europe, Chagas disease is an emerging public health issue in non endemic countries. In Italy, where no specific policy has yet been developed, the Centre for International Health of the University of Bologna is carrying out the project "Chagas disease in a non endemic country: a study in the district of Bologna". A multidisciplinary and multi-method approach was adopted to estimate the problem and its impact in our territory. A retrospective analysis was performed searching several databases in order to collect information concerning the demographic and epidemiological profile of Latin American migrants coming from endemic countries. At the same time, a preliminary ethnographic research was conducted to start unveiling the main socio-anthropological characteristics of this population, thanks to the involvement of key informants and community associations. According to preliminary findings, Chagas disease is a present and possibly increasing reality in our territory. Due to the particular features of the affected population, socio-cultural variables have to be considered for their impact on the visibility of the condition and on health seeking behaviors.

  3. 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.

  4. 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. PMID:26677188

  5. Relationship between the Indian summer monsoon and the large-scale circulation variability over the Mediterranean

    NASA Astrophysics Data System (ADS)

    Rizou, Despoina; Flocas, Helena A.; Athanasiadis, Panos; Bartzokas, Aristides

    2015-01-01

    In this study the impact of the Indian summer monsoon on the large scale variability of the atmospheric circulation over the Mediterranean is investigated on an inter-annual time scale. Composite and correlation analysis results are presented, outlining different circulation patterns in the upper and lower troposphere for strong and weak monsoon years respectively. For this purpose ERA-40 Reanalysis monthly mean data at various isobaric levels together with the standardized All India Rainfall Index for boreal summer (June-July-August-September) of a 44-year period were employed. During strong monsoon years many atmospheric circulation systems appear strengthened over Eurasia, resembling a well-organized Rossby wave train over the area. In the upper troposphere a meridional shift of the jet streams over the examined area was also identified during extreme monsoon years. On the other hand, in the lower troposphere enhanced northerlies (Etesians) appear to dominate over Eastern Mediterranean along with intensified subsidence during strong monsoon years.

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

    NASA Astrophysics Data System (ADS)

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

    2016-09-01

    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.

  7. 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

  8. Asian summer monsoon onset barrier and its formation mechanism

    NASA Astrophysics Data System (ADS)

    Liu, Boqi; Liu, Yimin; Wu, Guoxiong; Yan, Jinghui; He, Jinhai; Ren, Suling

    2015-08-01

    The onset process of Asian summer monsoon (ASM) is investigated based on diagnostic analysis of observations of precipitation and synoptic circulation. Results show that after the ASM commences over the eastern Bay of Bengal (BOB) around early May, the onset can propagate eastwards towards the South China Sea and western Pacific but is blocked on its westward propagation along the eastern coast of India. This blocking, termed the "monsoon onset barrier (MOB)", presents a Gill-type circulation response to the latent heating released by BOB monsoon convection. This convective condensation heating generates summertime (wintertime) vertical easterly (westerly) shear to its east (west) and facilitates air ascent (descent). The convection then propagates eastward but gets trapped on its westward path. To the east of the central BOB, the surface air temperature (SAT) cools faster than the underlying sea surface temperature (SST) due to monsoon onset. Thus more sensible heat flux supports the onset convection to propagate eastward. To the west of the central BOB, however, the land surface sensible heating over the Indian Peninsula is strengthened by the enhanced anticyclone circulation and air descent induced by the BOB monsoon heating. The strengthened upstream warm horizontal advection then produces a warm SAT center over the MOB region, which together with the in situ cooled SST reduces the surface sensible heating and atmospheric available potential energy to prevent the occurrence of free convection. Therefore, it is the change in both large-scale circulation and air-sea interaction due to BOB summer monsoon onset that contributes to the MOB formation.

  9. 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.

  10. 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

  11. Toward a more holistic understanding of filicide: a multidisciplinary analysis of 32 years of U.S. arrest data.

    PubMed

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

    2014-03-01

    Filicide is the killing of 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 the victims were under a year old; over two-thirds of the victims 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 aged 18-45. 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

  12. 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.

  13. 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.

  14. 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

  15. Global Monsoon Rainfall - What the future holds?

    NASA Astrophysics Data System (ADS)

    Endo, H.; Kitoh, A.; Kumar, K.; Cavalcanti, I. F.; Goswami, P.; Zhou, T.

    2012-12-01

    We provide a latest view of global as well as regional monsoonal rainfall and their changes in the twenty-first century as projected by state-of-the-art climate models participated in the Coupled Model Intercomparison Project phase 5 (CMIP5). The global monsoon area (GMA) defined based on the annual range in precipitation will expand mainly over the central to eastern tropical Pacific, the southern Indian Ocean, and eastern Asia. The global monsoon intensity (GMI) and the global monsoon total precipitation (GMP) are likely to increase, implying that monsoon-related precipitation will remarkably increase in a warmer climate. Heavy precipitation indices are projected to increase much more than the mean precipitation, and their percentage changes depend more on the emission scenario compared to those for mean precipitation. Over the Asian monsoon domain, median increase rate for precipitation is larger than that over other monsoon domains, indicating that the sensitivity of Asian monsoon to global warming is stronger than that of other monsoons. For seasonal progress of monsoon rainfall, CMIP5 models project that the monsoon retreat dates will delay, while the onset dates will either advance or show no change, resulting in lengthening of the monsoon season. It is found that the increase of the global monsoon precipitation can be attributed to the increases of moisture convergence due to increased water vapor in the air column and surface evaporation, offset to a certain extent by the weakening of the monsoon circulation (Figure 1).Figure 1: Time series of anomalies during summer season (%; 20 years running mean) relative to the base period average (1986-2005) over the land global monsoon domain for (a) precipitation (mm day-1), (b) evaporation (mm day-1), (c) water vapor flux convergence in the lower (below 500hPa) troposphere (mm day-1), and (d) wind convergence in the lower troposphere (10-3 kg m-2 s-1), based on 23 CMIP5 model monthly outputs. Historical (grey

  16. 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.

  17. Interannual variability of South American monsoon circulation

    NASA Astrophysics Data System (ADS)

    Alonso Gan, Manoel; Rafaele Araújo Lima, Jeane

    2016-04-01

    The South America Monsoon System (SAMS) is responsible for influencing the atmospheric circulation and precipitation over most of tropical South America (SA) during the summer season. Studies for aiming to understand the temporal variability of this system have great value to the scientific community, because the processes that control the monsoon climate are not totally clear. Thus, the main objective of this research is to investigate the possible large-scale climatic factors and the remote interaction mechanisms, which may be associated with summer season interannual variability focusing on identifying the main differences between dry and wet extremes rainy season in the South-eastern Amazon Basin (SAB), Central-West (WC) and Southeast (SE) of Brazil, which are areas influenced by the summer monsoon regime. For such analyzes, Pearson correlations, quantile method and composite analysis were used during the period from 1979 to 2014. The correlation between precipitation anomaly in SAB and the sea surface temperature anomaly (SSTA) and wind at 850hPa and 300hPa indicate El Niño-Southern Oscillation (ENSO) influence. Precipitation anomalies in WC did not show significant correlation with SSTA. However, a pattern similar to ENSO Modoki type was observed in the composite analysis. At 850 hPa, the presence of an anomalous cyclonic (anticyclonic) circulation was observed over the central region of SA during wet (dry) summers seasons. Over SE region of Brazil, a dipole SSTA pattern over the South Atlantic was identified, as well the presence of anomalous circulations with an equivalent barotropic structure over these SSTA areas. This pattern is more evident in case of dry summer on the SE. At 300 hPa, the wave train between 30°S-60°S was observed presenting a feature curvature from 120°W reaching SA, similar to the Pacific-South American pattern (PSA). Analysis of the summer interannual variability indicated the manifestation of wet summers more frequently than dry

  18. A seamless approach to assessing monsoon simulations in the Met Office Unified Model

    NASA Astrophysics Data System (ADS)

    Levine, R. C.; Boo, K. O.; Martin, G. M.; Milton, S. F.; Mitra, A.; Sellar, A. A.; Willett, M. R.

    2009-04-01

    We present an assessment of monsoons as simulated by the latest configurations of the Met Office Unified Model. These consist of models of varying complexity that are used for Numerical Weather Prediction (NWP), climate, and seasonal prediction. A comparison is made between the model biases in different monsoon regions for the different configurations, giving an insight into the nature of the main systematic errors, and also of the time-scales involved in their development. Both the mean state and the variability are assessed using a metric-based approach. The main model bias in the Indian monsoon region is the relatively low precipitation over Indian land. This has been significantly improved in the latest atmospheric component of the climate model, mainly due to changes in the CAPE closure in the convection scheme, which are aimed at reducing the tendency for strong intermittent deep convection. A more detailed comparison of the model with ERA re-analysis data is made for the onset and the pre-monsoon period of the Indian summer monsoon, giving an insight into the impact of various changes to the model. The emphasis is placed on the impacts of the timing of convection, the development of the monsoon jet, the impact of cyclonic vortices, and the moistening rates over India. The interannual variability is further examined through analysis of the ENSO-monsoon teleconnection, the link between El Nino/La Nina events and below/above average rainfall over India, which is assessed using a metric-based approach.

  19. 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

  20. 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.

  1. 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.

  2. Non-local Impact of South and East Asian Aerosols on Monsoon Onset and Withdrawal

    NASA Astrophysics Data System (ADS)

    Bollasina, M. A.; Bartlett, R. E.; Booth, B.; Dunstone, N. J.; Marenco, F.

    2015-12-01

    The powerful Asian monsoon is of vital importance to the billions of people who are reliant on its rainfall, especially considering that society within its domain is largely agrarian. This monsoon system comprises smaller regional components, including the Indian monsoon and East Asian monsoon. These components are linked to one another through large scale circulation. The impacts of rapidly increasing anthropogenic aerosols over Asia on the monsoon have been widely studied. However, most studies consider only regional impacts, and not the subsequent effects on other geographical components of the system. We use observational and modelling methods to investigate the links between the regional components of the Asian monsoon and how they are affected by aerosols. Satellite observations of aerosol optical depth are used in conjunction with precipitation and atmospheric reanalysis data to investigate the problem at interannual timescales. Modelling experiments using HadGEM2-ES and GFDL CM3 are used to look at longer timescales and the potential influence of long term feedbacks. The HadGEM2 experiments use three time-evolving future anthropogenic aerosol emissions scenarios with the same time-evolving greenhouse gases. The GFDL CM3 experiments are forced by historical regional anthropogenic aerosol emissions. Using these methods, we look at the separate impact that South and East Asian aerosols have on monsoon onset and withdrawal. We focus on impacts in regions non-local to the aerosol source. We will also present proposed mechanisms for the apparent effects based on analysis of large scale circulation and atmospheric heating.

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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.

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

    DOE PAGES

    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)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

  10. BOBMEX: The Bay of Bengal Monsoon Experiment.

    NASA Astrophysics Data System (ADS)

    Bhat, G. S.; Gadgil, S.; Hareesh Kumar, P. V.; Kalsi, S. R.; Madhusoodanan, P.; Murty, V. S. N.; Prasada Rao, C. V. K.; Babu, V. Ramesh; Rao, L. V. G.; Rao, R. R.; Ravichandran, M.; Reddy, K. G.; Sanjeeva Rao, P.; Sengupta, D.; Sikka, D. R.; Swain, J.; Vinayachandran, P. N.

    2001-10-01

    The first observational experiment under the Indian Climate Research Programme, called the Bay of Bengal Monsoon Experiment (BOBMEX), was carried out during July-August 1999. BOBMEX was aimed at measurements of important variables of the atmosphere, ocean, and their interface to gain deeper insight into some of the processes that govern the variability of organized convection over the bay. Simultaneous time series observations were carried out in the northern and southern Bay of Bengal from ships and moored buoys. About 80 scientists from 15 different institutions in India collaborated during BOBMEX to make observations in most-hostile conditions of the raging monsoon. In this paper, the objectives and the design of BOBMEX are described and some initial results presented. During the BOBMEX field phase there were several active spells of convection over the bay, separated by weak spells. Observation with high-resolution radiosondes, launched for the first time over the northern bay, showed that the magnitudes of the convective available potential energy (CAPE) and the convective inhibition energy were comparable to those for the atmosphere over the west Pacific warm pool. CAPE decreased by 2-3 kJ kg-1 following convection, and recovered in a time period of 1-2 days. The surface wind speed was generally higher than 8 m s-1. The thermohaline structure as well as its time evolution during the BOBMEX field phase were found to be different in the northern bay than in the southern bay. Over both the regions, the SST decreased during rain events and increased in cloud-free conditions. Over the season as a whole, the upper-layer salinity decreased for the north bay and increased for the south bay. The variation in SST during 1999 was found to be of smaller amplitude than in 1998. Further analysis of the surface fluxes and currents is expected to give insight into the nature of coupling.

  11. Space-Time Structure of Monsoon Interannual Variability.

    NASA Astrophysics Data System (ADS)

    Terray, Pascal

    1995-11-01

    The analysis of corrected ship reports [sea level pressure (SLP), sea surface temperature (SST), air temperature (AT)] and corrected land data (SLP, AT, rainfall) in the Indian sector reveals the existence of two low-frequency modes of monsoon variability during the 1900-1970 period. A definite biennial (B) mode exists on the SLP fields. This B oscillation is unambiguously linked with a southwest-northeast SLP anomaly gradient. During the summer monsoon, the B SLP pattern can be interpreted as an expansion/contraction of the monsoon activity since this mode is strongly coupled with rainfall variations over peninsular India. A strong low-frequency (LF) mode with period spanning 4-6 years is also seen on SLP fields over the Indian Ocean and subcontinent. The variance associated with this band is typically more important than the one observed for the B mode, and its spatial mark is also strikingly different since it is linked with a global pattern of variation. This mode has also a strong influence on the Indian summer rainfall fluctuations, particularly on the Ghats and in the Indo-Gangetic plains.The amplitude of these oscillations varies widely during the 1900-1970 period. The LF mode is well defined during 1900-1923 and 1947-1970. There is a tendency for the energy associated with the B mode to decrease on the land while it increases over the Indian Ocean during the whole 1900-1970 interval.Although these two timescales exist also on SST fields, cross-spectral analysis shows that ocean-atmosphere interactions are much stronger at the B timescale. This result stresses the B nature of the monsoon system.The existence of these interannual signals in the Indian areas where the annual cycle is so strong raises difficult problems: How can climatic anomalies persist for several years in spite of strong seasonality? Or, still more intriguing, how can be explained the persistence of climatic anomalies during one year and the appearance of opposite sign climatic anomalies

  12. TIGERZ I: Aerosols, Monsoon and Synergism

    NASA Astrophysics Data System (ADS)

    Holben, B. N.; Tripathi, S. N.; Schafer, J. S.; Giles, D. M.; Eck, T. F.; Sinyuk, A.; Smirnov, A.; Krishnmoorthy, K.; Sorokin, M. G.; Newcomb, W. W.; Tran, A. K.; Sikka, D. R.; Goloub, P.; O'Neill, N. T.; Abboud, I.; Randles, C.; Niranjan, K.; Dumka, U. C.; Tiwari, S.; Devara, P. C.; Kumar, S.; Remer, L. A.; Kleidman, R.; Martins, J. V.; Kahn, R.

    2008-12-01

    The Indo-Gangetic Plain of northern India encompasses a vast complex of urban and rural landscapes, cultures that serve as anthropogenic sources of fine mode aerosols mixed with coarse mode particles transported from SW Asia. The summer monsoon and fall Himalayan snowmelt provide the agricultural productivity to sustain an extremely high population density whose affluence is increasing. Variations in the annual monsoon precipitation of 10% define drought, normal and a wet season; the net effects on the ecosystems and quality of life can be dramatic. Clearly investigation of anthropogenic and natural aerosol impacts on the monsoon, either through the onset, monsoon breaks or end points are a great concern to understand and ultimately mitigate. Many national and international field campaigns are being planned and conducted to study various aspects of the Asian monsoon and some coordinated under the Asian Monsoon Years (AMY) umbrella. A small program called TIGERZ conducted during the pre-monsoon of 2008 in North Central India can serve as a model for contributing significant resources to existing field programs while meeting immediate project goals. This poster will discuss preliminary results of the TIGERZ effort including ground-based measurements of aerosol properties in the I-G from AERONET and synergism with various Indian programs, satellite observations and aerosol modeling efforts.

  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

    2016-06-01

    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. Interactive Aspects of the Indian and the African Summer Monsoon Systems

    NASA Astrophysics Data System (ADS)

    Sanjeeva Rao, P.; Sikka, D. R.

    2007-09-01

    This study addresses an understanding of the possible mutual interactions of sub-seasonal variability of the two neighboring regional monsoon systems through data analysis. The NCEP/NCAR re-analysis and OLR data for three years was used to reveal the large-scale organization of convective episodes on synoptic (~5 days) and low frequency (15 50 day) scales. It is found that synoptic scale organization over both the sectors is influenced by the eastward migration of large-scale convective episodes associated with the Madden Julian Oscillation (MJO) on the low frequency scale. The organization of convection associated with the African monsoon on the synoptic scale is influenced by the pulsatory character of lower mid-troposphere and upper troposphere wind regimes moving westward over the African sector. Over the Indian region formation of low pressure areas and depressions in the monsoon trough occur in an overlapping manner under an envelope of low frequency seasonal oscillation. We have also found some correspondence between the summer monsoon rainfall over tropical North Africa and India on a decadal basis, which would suggest a common mode of multi-decadal variability in the two monsoon systems. The study points out the need to organize simultaneous field campaigns over the Indian and the African monsoon regions so as to bring out observational features of possible interactions between the two neighboring systems, which could then be validated through modeling studies.

  15. 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.

  16. A qualitative study on sea surface temperature over the tropical Indian Ocean and performance of Indian summer monsoon

    NASA Astrophysics Data System (ADS)

    Singh, Umesh Kumar; Singh, Gyan Prakash

    2012-08-01

    A careful analysis of the sea surface temperature (SST) over the tropical Indian Ocean using the available SST data sets (namely, Hadley Center Ice SST, tropical rainfall measuring mission microwave imager SST, and optimum interpolation SST) at different time scales has been presented in the present study. By simple visual inspection of the SST plots, it has been shown that the qualitative prediction of Indian summer monsoon condition (weak/normal) and northern limit of monsoon (NLM) can be possible a month in advance using SST. The present qualitative study may be useful for common man to know the behavior of summer monsoon well a month in advance. Therefore, the qualitative study may enable the common man to show the application of satellite data to bring out the information regarding the onset of summer monsoon and related performance of Indian summer monsoon well in advance.

  17. 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.

  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. A hemispheric climatology of monsoon depressions

    NASA Astrophysics Data System (ADS)

    Hurley, J. V.; Boos, W.

    2012-12-01

    Monsoon depressions are large (1000-2000 km diameter) cyclonic low pressure systems having organized deep convection, best known for forming in the Bay of Bengal and migrating northwest over northern India in the monsoon trough. About 3 to 5 of these systems occur during each monsoon season, contributing about half of the Indian summer rainfall. Despite their importance as a precipitation source, their dynamics are poorly constrained. Furthermore, although they do occur elsewhere, such as around Australia and in the southern Indian Ocean, there does not exist a collective inventory of these systems outside of the Bay of Bengal region. Here we present a climatology of monsoon depressions produced from the ERA-Interim Reanalysis. Feature tracks are identified using an automated tracking algorithm (K. Hodges' TRACK code) applied to the 850 hPa relative vorticity field for local summer, 1989 to 2003. Using criteria based on relative vorticity and sea level pressure, cyclonic low pressure systems are separated into different intensity categories, one of which corresponds to the definition for monsoon depressions used by the India Meteorological Department. The resultant distribution of storms obtained for the Bay of Bengal region compares well with a previously compiled climatology of monsoon depressions that was limited to the region surrounding India. Having validated our ability to identify monsoon depressions in their classic genesis region near India, we then extend the methods to include the western Pacific, Australia, and the southern Indian Ocean. Track distributions and composite structures of monsoon depressions for these different regions will be presented.

  20. 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.

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. Multidisciplinary Design Of Hot Composite Structures

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C.; Singhal, Surendra N.

    1996-01-01

    Unified computer code developed to implement multidisciplinary approach to design and analysis of composite-material structures that must withstand high temperatures. Code modular: includes executive module communicating with and coordinating other modules performing calculations pertaining to traditionally separate disciplines like those of acoustics, structural vibrations, structural loads, and thermal effects. Essential feature, finite-element numerical simulation of relevant physical phenomena according to applicable disciplines. Same finite-element mesh used in thermal, vibrational, and structural analyses; minimizing data-preparation time and eliminating errors incurred in transforming temperatures from one finite-element mesh to another.

  7. Influence of the Atlantic zonal mode on monsoon depressions in the Bay of Bengal during boreal summer

    NASA Astrophysics Data System (ADS)

    Pottapinjara, Vijay; Girishkumar, M. S.; Ravichandran, M.; Murtugudde, R.

    2014-06-01

    The influence of the Atlantic Zonal Mode (AZM) or the Atlantic Niño on monsoon depressions in the Bay of Bengal during the boreal summer (June-August) is studied. Our analysis shows that there is a statistically significant difference in the number of monsoon depressions in the Bay of Bengal between the warm and cold phases of the AZM; more (fewer) monsoon depressions form during the cold (warm) phase of AZM. It also shows that there are differences in spatial pattern of trajectories of monsoon depressions; during the cold phase of AZM, the tracks are relatively long and seem to cluster along the axis of core monsoon region compared to the warm phase of AZM. The analysis indicates an increase (a reduction) in low-level cyclonic vorticity and midtropospheric humidity but a reduction (an increase) in vertical wind shear due to anomalous circulation pattern. All of these changes are favorable for the enhancement (suppression) of monsoon depressions during the cold (warm) phase of the AZM. Our analysis further shows a teleconnection pathway by which the AZM can influence the remote Indian Ocean. This could have implications for enhancing monsoon prediction skill, especially during non-El Niño-Southern Oscillation years.

  8. 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

  9. Recommending Research Profiles for Multidisciplinary Academic Collaboration

    ERIC Educational Resources Information Center

    Gunawardena, Sidath Deepal

    2013-01-01

    This research investigates how data on multidisciplinary collaborative experiences can be used to solve a novel problem: recommending research profiles of potential collaborators to academic researchers seeking to engage in multidisciplinary research collaboration. As the current domain theories of multidisciplinary collaboration are insufficient…

  10. 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

  11. 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).

  12. Multidisciplinary teamwork and communication training.

    PubMed

    Deering, Shad; Johnston, Lindsay C; Colacchio, Kathryn

    2011-04-01

    Every delivery is a multidisciplinary event, involving nursing, obstetricians, anesthesiologists, and pediatricians. Patients are often in labor across multiple provider shifts, necessitating numerous handoffs between teams. Each handoff provides an opportunity for errors. Although a traditional approach to improving patient outcomes has been to address individual knowledge and skills, it is now recognized that a significant number of complications result from team, rather than individual, failures. In 2004, a Sentinel Alert issued by the Joint Commission revealed that most cases of perinatal death and injury are caused by problems with an organization's culture and communication failures. It was recommended that hospitals implement teamwork training programs in an effort to improve outcomes. Instituting a multidisciplinary teamwork training program that uses simulation offers a risk-free environment to practice skills, including communication, role clarification, and mutual support. This experience should improve patient safety and outcomes, as well as enhance employee morale. PMID:21440817

  13. Impact of biennial SST oscillation on the Southeast Asian summer monsoon

    NASA Astrophysics Data System (ADS)

    Kim, J.; Kim, K. Y.

    2014-12-01

    How the biennial oscillation of global SST, one of the main components of ENSO, affects the Southeast Asia summer monsoon is analyzed. The biennial mode is extracted from the 142-year (1871-2012) Extended Reconstruction SST version 3 data using cyclostationary EOF (CSEOF) analysis. Based on regression analysis in CSEOF space, evolutions of key atmospheric variables are obtained to be consistent with the long-term variation of the biennial mode. Atmospheric variables are derived from the twentieth century (20C) reanalysis version 2 data. The biennial oscillation, primarily in the tropical Pacific, influences the monsoons in the Indo-Pacific region. Summer monsoonal change can be explained in terms of the change in monsoon precipitation accompanied with low-level moisture convergence and large-scale atmospheric circulation. In the equatorial region, SST anomaly directly triggers the vertical motion and horizontal wind such that zonal circulation across the Pacific and Indian Oceans is set up. In the subtropical Asian region, both cyclonic or anticyclonic circulation over the northwestern Pacific and the meridional circulation over the Indo-Pacific region induced by the equatorial SST change affects the Southeast Asian monsoon, and henceforth the monsoon precipitation. When positive SST anomaly develops in the eastern tropical Pacific, precipitation decreases over the tropical Indian Ocean and the Maritime Continent (10°S-5°N, 40°-150°E) and increases over Southeast Asia (5°N-20°N, 90°-150°E). With negative SST anomaly in the eastern tropical Pacific, the situation reverses. Based on the spatio-temporal evolution patterns for key physical variables and corresponding long-term variability, physical link through atmosphere-ocean interactions is explored between the biennial mode of SST and the Southeast Asian summer monsoon.

  14. 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.

  15. 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.

  16. Establishing a framework for building multidisciplinary programs.

    PubMed

    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.

  17. 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

  18. A crisis in chronic pain care: an ethical analysis. Part three: Toward an integrative, multi-disciplinary pain medicine built around the needs of the patient.

    PubMed

    Giordano, James; Schatman, Michael E

    2008-01-01

    A number of variables have contributed to the current crisis in chronic pain care and are affected by, and affect, the philosophies and politics that influence the socio-economic climate of the American healthcare system. Thus, we posit that managing the crisis in chronic pain care in the United States is contingent upon the development of a multi-focal healthcare paradigm that more thoroughly enables and fortifies research, its translation (in education and practice), and the implementation of, and support for, both the curative and healing approaches in medicine in general, and pain care specifically. These steps necessitate re-examination, if not revision of the health care system and its economics. The ethical imperative to consider and prudently employ cutting-edge diagnostic and therapeutic technologies in pain medicine is obligatory. However, "supply side prudence" is of little value if "demand side accessibility" is lacking. Revisions to health insurance plans advocated by the in-coming administration seek to create uniformity in basic health care services based upon re-assessment of the clinical effectiveness (versus merely cost) of treatments, including those that are "high tech." These plans attempt to allow every patient a more complete ability to deliberatively work with physicians to access those services and resources that maximize health functioning and goals. But even given these revisions, authentic pain care must take into account the interactive contexts of the painient individual. The biopsychosocial model of chronic pain management may have significant practical and ethical worth in this regard. A system of pain treatment operating from a biopsychosocial perspective necessitates integrative multi-disciplinarity. We propose a tiered, multi-disciplinary paradigm based upon the differing needs of each specific patient. But establishing such a system does not guarantee access, and distribution of these services and resources requires economic

  19. A crisis in chronic pain care: an ethical analysis. Part three: Toward an integrative, multi-disciplinary pain medicine built around the needs of the patient.

    PubMed

    Giordano, James; Schatman, Michael E

    2008-01-01

    A number of variables have contributed to the current crisis in chronic pain care and are affected by, and affect, the philosophies and politics that influence the socio-economic climate of the American healthcare system. Thus, we posit that managing the crisis in chronic pain care in the United States is contingent upon the development of a multi-focal healthcare paradigm that more thoroughly enables and fortifies research, its translation (in education and practice), and the implementation of, and support for, both the curative and healing approaches in medicine in general, and pain care specifically. These steps necessitate re-examination, if not revision of the health care system and its economics. The ethical imperative to consider and prudently employ cutting-edge diagnostic and therapeutic technologies in pain medicine is obligatory. However, "supply side prudence" is of little value if "demand side accessibility" is lacking. Revisions to health insurance plans advocated by the in-coming administration seek to create uniformity in basic health care services based upon re-assessment of the clinical effectiveness (versus merely cost) of treatments, including those that are "high tech." These plans attempt to allow every patient a more complete ability to deliberatively work with physicians to access those services and resources that maximize health functioning and goals. But even given these revisions, authentic pain care must take into account the interactive contexts of the painient individual. The biopsychosocial model of chronic pain management may have significant practical and ethical worth in this regard. A system of pain treatment operating from a biopsychosocial perspective necessitates integrative multi-disciplinarity. We propose a tiered, multi-disciplinary paradigm based upon the differing needs of each specific patient. But establishing such a system does not guarantee access, and distribution of these services and resources requires economic

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

    PubMed

    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

  1. 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

  2. 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.

  3. 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.

  4. Relationship between tropospheric temperature and Indian summer monsoon rainfall as simulated by RegCM3

    NASA Astrophysics Data System (ADS)

    Pattnayak, K. C.; Panda, S. K.; Saraswat, Vaishali; Dash, S. K.

    2016-05-01

    Relationship between rainfall and tropospheric temperature (TT) has been examined over the Indian subcontinent during four seasons of the year using Regional Climate Model Version 3.0 (RegCM3). The model has been integrated at 55 km horizontal resolution over India during the years 1980-2000 with prescribed lateral boundary forcing from the 40 years re-analysis (ERA40) of the European Centre for Medium-range Weather Forecasts. Results of this study show that RegCM3 in general is able to capture the spatial distributions of rainfall in all the seasons as compared to the corresponding IMD0.5 gridded rainfall. The model has simulated warmer TT over the Himalayan region in all the seasons as compared to ERA40. However, it is well captured over the peninsular India and the oceanic regions. In the model, larger warming by about 0.5 °C over the northwest and Central India in the summer monsoon months might have lead to lower surface pressure there. Also, the vertical extent of the monsoon trough is found to be up to 500 hPa in the model as compared to that in NCEP/NCAR reanalysis. As a consequence, the simulated monsoon circulation and rainfall are stronger than those observed. The two most important rainfall seasons, the summer monsoon and winter are reasonably well simulated with correlation coefficients (CC) of 0.60 and 0.59 respectively significant at 99 % confidence level with the corresponding observed values of IMD0.5. Further, Indian summer monsoon rainfall (ISMR) and TT during the contrasting monsoon years are also close to their respective observed values. Temporal CCs between the TT over Tibet, Pakistan and Central India during the summer monsoon season and gridded ISMR values reveals that the TT over Pakistan has been better correlated with the ISMR than those over Tibet and Central India. This relationship has been well supported by the model simulations.

  5. 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

  6. 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

  7. 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

  8. A Multidisciplinary Approach to Improving SCIP Compliance.

    PubMed

    Huntington, Ciara R; Strayer, Melissa; Huynh, Toan; Green, John M

    2015-07-01

    The Surgical Care Improvement Project (SCIP) is a national program aimed at reducing perioperative complications and is a quality benchmark metric for Centers for Medicare and Medicaid Services. This study evaluates whether a multidisciplinary program improved an institution's compliance with SCIP measures. Analysis of the facility's performance data identified three key areas of SCIP noncompliance: 1) timely discontinuation of perioperative antibiotics and urinary catheters, 2) initiation of venous thromboembolism prophylaxis, and 3) perioperative beta blocker administration. Multidisciplinary teams collaborated with providers and department chairs in reviewing and enable SCIP compliance. Anesthesia staff managed preoperative antibiotics. SCIP-compliant order sets, venous thromboembolism pop-up alerts, and progress note templates were added to the electronic medical record. Standardized education was provided to explain SCIP requirements, review noncompliant cases, and update teams on SCIP performance. Data were captured from January 2009 to March 2014. Ten SCIP fallouts were reported for general surgery specialties in January 2013, when the SCIP compliance project launched. Specifically, colon-related surgery achieved 100 per cent compliance. Six months after implementation, overall SCIP compliance at our institution improved by 65 per cent (from 90.7-98.6% compliance). PMID:26140888

  9. A Multidisciplinary Approach to Improving SCIP Compliance.

    PubMed

    Huntington, Ciara R; Strayer, Melissa; Huynh, Toan; Green, John M

    2015-07-01

    The Surgical Care Improvement Project (SCIP) is a national program aimed at reducing perioperative complications and is a quality benchmark metric for Centers for Medicare and Medicaid Services. This study evaluates whether a multidisciplinary program improved an institution's compliance with SCIP measures. Analysis of the facility's performance data identified three key areas of SCIP noncompliance: 1) timely discontinuation of perioperative antibiotics and urinary catheters, 2) initiation of venous thromboembolism prophylaxis, and 3) perioperative beta blocker administration. Multidisciplinary teams collaborated with providers and department chairs in reviewing and enable SCIP compliance. Anesthesia staff managed preoperative antibiotics. SCIP-compliant order sets, venous thromboembolism pop-up alerts, and progress note templates were added to the electronic medical record. Standardized education was provided to explain SCIP requirements, review noncompliant cases, and update teams on SCIP performance. Data were captured from January 2009 to March 2014. Ten SCIP fallouts were reported for general surgery specialties in January 2013, when the SCIP compliance project launched. Specifically, colon-related surgery achieved 100 per cent compliance. Six months after implementation, overall SCIP compliance at our institution improved by 65 per cent (from 90.7-98.6% compliance).

  10. Multidisciplinary approaches to the pressure ulcer problem.

    PubMed

    Bogie, Kath M; Ho, Chester H

    2007-10-01

    Multiple factors affect the specific condition and overall clinical profile of individuals at risk for chronic wounds. The complexity of the pressure ulcer problem lends itself to the application of the National Institute of Health Roadmap Initiative that encourages interdisciplinary research and new organizational models. An overview of research studies relevant to telemedicine and neuromuscular electrical stimulation in the care and prevention of pressure ulcers as well as preliminary results of an innovative multidisciplinary skin care team approach to the primary and tertiary prevention of pressure ulcers are encouraging. The team's pilot study results indicate that patients are satisfied with telehealth provision of care; however, literature and experience also suggest that discrepancies in the inter-rater assessment of wounds using digital photography remain, particularly with regard to wound dimension variables assessed (P<0.01). In another endeavor, the skin care team developed a Longitudinal Analysis with Self-Registration statistical algorithm to assess the effects of electrical stimulation; in a preliminary study, this tool documented improvement in gluteus maximus health and resultant ability to withstand pressure. As the number of groups pursuing multidisciplinary research and care increases, so, too, will the evidence base required to address these common, and complex, chronic wounds. PMID:17978412

  11. 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.

  12. 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

  13. 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

  14. 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.

  15. Non-linear regime shifts in Holocene Asian monsoon variability: potential impacts on cultural change and migratory patterns

    NASA Astrophysics Data System (ADS)

    Donges, J. F.; Donner, R. V.; Marwan, N.; Breitenbach, S. F. M.; Rehfeld, K.; Kurths, J.

    2015-05-01

    The Asian monsoon system is an important tipping element in Earth's climate with a large impact on human societies in the past and present. In light of the potentially severe impacts of present and future anthropogenic climate change on Asian hydrology, it is vital to understand the forcing mechanisms of past climatic regime shifts in the Asian monsoon domain. Here we use novel recurrence network analysis techniques for detecting episodes with pronounced non-linear changes in Holocene Asian monsoon dynamics recorded in speleothems from caves distributed throughout the major branches of the Asian monsoon system. A newly developed multi-proxy methodology explicitly considers dating uncertainties with the COPRA (COnstructing Proxy Records from Age models) approach and allows for detection of continental-scale regime shifts in the complexity of monsoon dynamics. Several epochs are characterised by non-linear regime shifts in Asian monsoon variability, including the periods around 8.5-7.9, 5.7-5.0, 4.1-3.7, and 3.0-2.4 ka BP. The timing of these regime shifts is consistent with known episodes of Holocene rapid climate change (RCC) and high-latitude Bond events. Additionally, we observe a previously rarely reported non-linear regime shift around 7.3 ka BP, a timing that matches the typical 1.0-1.5 ky return intervals of Bond events. A detailed review of previously suggested links between Holocene climatic changes in the Asian monsoon domain and the archaeological record indicates that, in addition to previously considered longer-term changes in mean monsoon intensity and other climatic parameters, regime shifts in monsoon complexity might have played an important role as drivers of migration, pronounced cultural changes, and the collapse of ancient human societies.

  16. 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).

  17. 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

  18. 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.

  19. 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

  20. Multidisciplinary Care of Laryngeal Cancer.

    PubMed

    Salvador-Coloma, Carmen; Cohen, Ezra

    2016-08-01

    Treatment of larynx cancer has changed dramatically over the past several years. Novel modalities of treatment have been introduced as organ preservation has been developed. In addition, new targeted therapies have appeared, and improvements in radiotherapeutic and surgical techniques have been introduced. Thus, a large variety of treatment options is increasing local control rates and overall survival; however, selecting the most appropriate treatment remains a challenging decision. This article focuses on the multidisciplinary care of early-stage and locally advanced larynx cancer and attempts to sum up different approaches. Moreover, it reviews state-of-the-art treatment in larynx preservation, which has been consolidated in recent years. PMID:27511718

  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.; 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.

  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.; 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.

  3. 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.

  4. Water vapor transport from the Indian monsoon region: the phenomenon of Atmospheric River

    NASA Astrophysics Data System (ADS)

    Raghav R., Sree; Mrudula, G.

    2016-05-01

    An Atmospheric/Tropospheric River (AR/TR) is a relatively narrow corridor of concentrated moisture where horizontal transport occurs in the lower atmosphere. They transport moisture from tropical regions towards the poles across the mid latitudes. Research of Atmospheric River over the Indian Monsoon region is not reported in literature. In this paper an attempt is made to examine the existence of AR in Indian Ocean and surrounding region. Meteorological parameters such as precipitable water, rainfall, air temperature and wind have been analyzed for the same. Analysis shows a clear evidence of the presence of Atmospheric River during the pre-monsoon and monsoon period. It is seen that there are variations in the origin, orientation, duration and also the formation of the river according to the vapor content in the Indian Ocean. During Elnino phase there is a pronounced transport of moisture through an Atmospheric River and also a high intensity transport occurs during monsoon period (JJA), even if moisture prevails over Indian monsoon region during other seasons also. Detailed results and extension to model forecasts will be presented in the paper.

  5. 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

  6. 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.

  7. [Multidisciplinary therapy of Tourette syndrome].

    PubMed

    Bábel, B Tamás; Németh, Attila; Gádoros, Júlia; Bihari, Katalin

    2003-02-01

    The marked fluctuation in symptoms with a spectrum of behavioral problems contribute to misdiagnosis of Tourette syndrome. The authors review the recent progress in diagnosis and management with an emphasis on multidisciplinary approach. Possible associations with various genes have been found in etiology of Tourette syndrome. Development of the disease comes of dopaminerg neurotransmission disorder resulting in cortico-striato-thalamic system dysfunction. Tics are brief movements or sounds that occur intermittently and unpredictably mimicking fragments of normal behavior. Diagnostic criteria are based on the motor and vocal phenomena and their dynamics. The key concept in management are the tic severity scaling correlating with quality of life measurements. Therapeutic interventions indicated at severe alteration in patient's quality of life. Treatment plan combines various drug protocols, psychotherapy and behavioral therapy which should be optimalized for most disabling symptom. Social isolation and self injurious behavior complicates the treatment resistant, severe cases. In these subgroup of patient, an adequate selection of stereotactic intervention could provide an effective control of tic severity or behavioral disorder. Tourette syndrome, as a typical neuropsychiatric disorder, is a striking example for improved efficacy of multidisciplinary approach.

  8. 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.

  9. Oncoplastic multidisciplinary meetings: a necessity or luxury?

    PubMed Central

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

    2011-01-01

    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. PMID:22043493

  10. 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

  11. Future precipitation extremes during summer monsoon in southern Pakistan

    NASA Astrophysics Data System (ADS)

    Zahid, Maida; Lucarini, Valerio

    2016-04-01

    Extreme precipitation events are considered as a hydro-meteorological hazard resulting in colossal damage worldwide. In Pakistan, the extreme precipitation events have increased in the recent decades particularly in the southern part (Sindh province). This region did not receive substantial amount of precipitation earlier, but now experiencing urban flooding almost every year causing loss of life, property, crops and infrastructure. The region lacks the information regarding the recurrence of extreme precipitation events. Therefore, there is a strong need for a reliable information of extremes over the upcoming decades for better regional planning. Although statistical methods based on extreme value theory (EVT) are the most relevant ones to study the extremes, but they are never been applied in Pakistan. To address this shortcoming, we use the peak over threshold (POT) approach to compute the return levels (RLs) of precipitation extremes, and also identify the regions most prone to them. In this study, we analyzed the summer monsoon daily precipitation measured at nine weather stations of Pakistan Meteorological Department over the period 1980-2013. The summer monsoon (JJAS) is preferred for the analysis, because most of the extreme precipitation occurs during this period. We apply POT approach to model the daily precipitation above a selected threshold for each station. Then, we estimate return levels (RLs) of precipitation extremes during summer monsoon in southern Pakistan (Sindh) for the next 5, 25, 50 and 100-years. Lastly, we compare the 5-years with 100-years RLs to indicate the stations most vulnerable to precipitation extremes in future. This work is funded by the Climate KIC, European Institute of Innovation and Technology, Germany.

  12. Orbital control of the western North Pacific summer monsoon

    NASA Astrophysics Data System (ADS)

    Wu, Chi-Hua; Chiang, John C. H.; Hsu, Huang-Hsiung; Lee, Shih-Yu

    2016-02-01

    Orbital forcing exerts a strong influence on global monsoon systems, with higher summer insolation leading to stronger summer monsoons in the Northern Hemisphere. However, the associated regional and seasonal changes, particularly the interaction between regional monsoon systems, remain unclear. Simulations using the Community Earth System Model demonstrate that the western North Pacific (WNP) summer monsoon responds to orbital forcing opposite to that of other major Northern Hemisphere monsoon systems. Compared with its current climate state, the simulated WNP monsoon and associated lower-tropospheric trough is absent in the early Holocene when the precession-modulated Northern Hemisphere summer insolation is higher, whereas the summer monsoons in South and East Asia are stronger and shift farther northward. We attribute the weaker WNP monsoon to the stronger diabatic heating of the summer Asian monsoon—in particular over the southern Tibetan Plateau and Maritime Continent—that in turn strengthens the North Pacific subtropical high through atmospheric teleconnections. By contrast, the impact of the midlatitude circulation changes on the WNP monsoon is weaker when the solar insolation is higher. Prior to the present WNP monsoon onset, the upper-tropospheric East Asian jet stream weakens and shifts northward; the monsoon onset is highly affected by the jet-induced high potential vorticity intrusion. In the instance of the extreme perihelion-summer, the WNP monsoon is suppressed despite a stronger midlatitude precursor than present-day, and the midlatitude circulation response to the enhanced South Asian precipitation is considerable. These conditions indicate internal monsoon interactions of an orbital scale, implying a potential mechanistic control of the WNP monsoon.

  13. 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

  14. 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

  15. Vocational rehabilitation: a multidisciplinary intervention.

    PubMed

    Gobelet, C; Luthi, F; Al-Khodairy, A T; Chamberlain, M A

    2007-09-15

    Vocational rehabilitation is by definition a multidisciplinary intervention in a process linked to the facilitation of return to work or to the prevention of loss of the work. Clinical staff in contact with a person who has lost his job (general practitioner, specialized physician) must promote vocational rehabilitation. Medical rehabilitation for those with disabilities, whether new or old, has to be followed without delay by vocational rehabilitation. It is even better if these two intertwined processes are overlapping. They involve many professionals including physiotherapists, occupational therapists, psychologists, vocational trainers, job counsellors, teachers, case-managers, job placement agencies. Vocational rehabilitation has a financial cost, borne by many state organizations (security, social system, social affairs) as well as by employers and private insurances, which are in case of accident, concerned by this process. However, the evidence suggests that this is recouped 2- to 10-fold as suggested by the British Society of Rehabilitation Medicine.

  16. 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

  17. On the Onset of the Planetary Scale Monsoon

    NASA Astrophysics Data System (ADS)

    Pasch, Richard Joseph

    A hypothesis, concerning the spatial scale of the onset of the Asian southwest monsoon of the Northern Hemispheric summer, is put forth. It is implied, from the large scale climatology of the tropospheric motion and temperature fields in May and June, that the monsoon onset is characterized by radical changes in the tropical circulations on a planetary scale. A suitable framework for the quantitative definition of this phenomenon, i.e., the atmospheric energetics in the zonal wavenumber domain, is reviewed. Global tropospheric wind and temperature data for periods surrounding the Indian monsoon onset cases of 1973, 1977 and 1979 are utilized. It is found that the kinetic and available potential energy of the sum of zonal wavenumbers 1, 2 and 3 (defined as the planetary scale waves) increase by about 30 to 50% on the time scale of about 1 week, corresponding to Indian (regional) onset. This increase characterizes the planetary scale onset. From the point of view of scale interactions, the observational calculations show that the planetary scale eddies, in general, supply available potential and kinetic energy to other (zonal mean and sub-planetary) scales during the onset although there are some interesting time variations. It is concluded that additional mechanisms must play the dominant roles in the planetary scale onset. To determine a more complete energetics for the onset using a dynamically more consistent set of atmospheric observations, an NWP experiment, for the 1979 onset case, is conducted. A global, multi-level, primitive equation spectral model containing a variety of physical effects parameterizations is described in detail. The results of a 96-hour prediction are compared to the observed circulation and rainfall patterns over the Indian Ocean region and the model is seen to reproduce the broad scale synoptic features of the onset fairly well. An analysis of the model diagnosed energetics (for the planetary scale waves) reveals that deep cumulus

  18. 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

  19. 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

  20. Atmospheric circulation feedback on west Asian dust and Indian monsoon rainfall

    NASA Astrophysics Data System (ADS)

    Kaskaoutis, Dimitris; Houssos, Elias; Gautam, Ritesh; Singh, Ramesh; Rashki, Alireza; Dumka, Umesh

    2016-04-01

    Classification of the atmospheric circulation patterns associated with high aerosol loading events over the Ganges valley, via the synergy of Factor and Cluster analysis techniques, has indicated six different synoptic weather patterns, two of which mostly occur during late pre-monsoon and monsoon seasons (May to September). The current study focuses on examining these two specific clusters that are associated with different mean sea level pressure (MSLP), geopotential height at 700 hPa (Z700) and wind fields that seem to affect the aerosol (mostly dust) emissions and precipitation distribution over the Indian sub-continent. Furthermore, the study reveals that enhanced aerosol presence over the Arabian Sea is positively associated with increased rainfall over the Indian landmass. The increased dust over the Arabian Sea and rainfall over India are associated with deepening of the northwestern Indian and Arabian lows that increase thermal convection and convergence of humid air masses into Indian landmass, resulting in larger monsoon precipitation. For this cluster, negative MSLP and Z700 anomalies are observed over the Arabian Peninsula that enhance the dust outflow from Arabia and, concurrently, the southwesterly air flow resulting in increase in monsoon precipitation over India. The daily precipitation over India is found to be positively correlated with the aerosol loading over the Arabian Sea for both weather clusters, thus verifying recent results from satellite observations and model simulations concerning the modulation of the Indian summer monsoon rainfall by the Arabian dust. The present work reveals that in addition to the radiative impacts of dust on modulating the monsoon rainfall, differing weather patterns favor changes in dust emissions, accumulation as well as rainfall distribution over south Asia.

  1. Modern monsoon extent and moisture dynamics over eastern Asian: evidence from precipitation and water vapor isotopes

    NASA Astrophysics Data System (ADS)

    Liu, Zhongfang; Kei, Yoshimura; Bowen, Gabriel J.; Tian, Lide

    2013-04-01

    The climate of eastern Asia is dominated by the Asia monsoon (AM) system, which controls seasonal patterns of moisture sources and transport to the region. Measurements of water isotopes can provide insight into monsoon extent and moisture dynamics. Here we present an analysis of a spatially dense network of precipitation isotopes (d18O and dD) from a ground-based network and water vapor dD retrieved from satellite measurements. The results show that isotopic seasonality for both precipitation and water vapor exhibits two distinctly different, spatially coherent modes. Summer-season isotope ratios are relatively low to the south of ~35°N and high to the north, with the transition between these zones reflecting the approximate northward extent of Asia summer monsoon influence. In the southern monsoon domain, low isotope values with relatively low precipitation d-excess (9.4‰ in SE China) in summer appear not to reflect the amount effect, but rather the dominance of monsoon moisture with long-distance transport from the Indian and southern Pacific oceans and continental convective recycling (contribute to about 30-48% moisture in SE China). In contrast, other seasons are dominated by dry continental masses, characterized by high d-excess (12.7‰) and isotope values. In northern China, a region that is beyond extent of monsoon, the moisture is derived overwhelmingly from the dry continental air masses. Here, water isotope ratios exhibit stronger temperature dependence, with enriched values in summer and depleted values in other seasons. The relatively low precipitation d-excess (<8‰) in northern China and inverse spatial isotope patterns between precipitation and water vapor across China during the summer further suggest that re-evaporation of falling raindrops is a key driver of water isotope behavior in northern China.

  2. Role of Anomalous States of Upper Tropospheric Circulation on Extremely Dry and Wet Summer Monsoon Events

    NASA Astrophysics Data System (ADS)

    Ahmad, S.; Koike, T.; Nishii, K.; Shrestha, M.

    2011-12-01

    Seasonal changes in wind pattern, monsoon, sometimes result in severe droughts and intense flooding in many parts of the world including South Asian countries like Pakistan. The livelihood of a vast population in Pakistan depends on agriculture and land use is strongly influenced by water-based ecosystems that depend on the monsoon rains. Furthermore, climate change studies undertaken so far reveal that action is essential in order to prevent long term damage to water cycle and thus of great concern to the community and stakeholders. Pakistan Summer Monsoon (PSM) is affected by both the disturbances from the tropical and the extratropical regions; however there is lack of understanding of physical mechanisms of PSM compared to other regional studies i.e. Indian Summer Monsoon (ISM) and South-East Asian Monsoon (SEAM). In our study, we applied heat and vorticity budgets, and wave train analysis to reveal the mechanisms of the extremely dry and wet PSM events associated with the anomalous upper tropospheric conditions. We found that the extremely dry (wet) PSM events were closely related with the anomalous cyclonic (anticyclonic) upper-tropospheric circulation around northwest of Pakistan, and mid-upper tropospheric cooling (warming) anomaly around Pakistan and to its north/northwest. We also found in addition to Rossby wave response due to the suppressed (enhanced) convective activities around monsoon regions, the midlatitude wave energy propagation emanating around cyclonic/anticyclonic anomaly around northwestern Atlantic, northeastern Atlantic, Europe or Mediterranean regions induced/reinforced/maintained the anomalous upper tropospheric cyclonic (anticyclonic) circulation around northwest of Pakistan during extremely dry (wet) PSM events. Therefore, devastating drought (flood) events over the PSM region resulting from weak (strong) convection anomalies are induced by both the tropical and extratropical processes.

  3. 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

  4. 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

  5. Regime shifts in Holocene Asian monsoon dynamics inferred from speleothems: Potential impacts on cultural change and migratory patterns

    NASA Astrophysics Data System (ADS)

    Donges, Jonathan F.; Donner, Reik V.; Marwan, Norbert; Breitenbach, Sebastian F. M.; Rehfeld, Kira; Kurths, Jürgen

    2014-05-01

    The Asian monsoon system has been recognized as an important potential tipping element in Earth's climate. A global warming-driven change in monsoonal circulation, potentially towards a drier and more irregular regime, would profoundly affect up to 60% of the global human population. Hence, to improve our understanding of this major climate system, it is mandatory to investigate evidence for nonlinear transitions in past monsoonal dynamics and the underlying mechanisms that are contained in the available palaeoclimatic record. For this purpose, speleothems are among the best available high-resolution archives of Asian palaeomonsoonal variability during the Holocene and well beyond. In this work, we apply recurrence networks, a recently developed technique for nonlinear time series analysis of palaeoclimate data (Donges et al., PNAS 108, 20422-20427, 2011), for detecting episodes with pronounced changes in Asian monsoon dynamics during the last 10 ka in oxygen isotope records from spatially distributed cave deposits covering the different branches of the Asian monsoon system. Our methodology includes multiple archives, explicit consideration of dating uncertainties with the COPRA approach and rigorous significance testing to ensure the robust detection of continental-scale changes in monsoonal dynamics. We identify several periods characterised by nonlinear changes in Asian monsoon dynamics (e.g., ~0.5, 2.2-2.8, 3.6-4.1, 5.4-5.7, and 8.0-8.5 ka before present [BP]), the timing of which suggests a connection to extra-tropical Bond events and rapid climate change (RCC) episodes during the Holocene. Interestingly, we furthermore detect an epoch of significantly increased regularity of monsoonal variations around 7.3 ka BP, a timing that is consistent with the typical 1.0-1.5 ka periodicity of Bond events but has been rarely reported in the literature so far. Furthermore, we find that the detected epochs of nonlinear regime shifts in Asian monsoon dynamics partly

  6. 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.

  7. 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.

  8. Assessment of South Asian Summer Monsoon Simulation in CMIP5-Coupled Climate Models During the Historical Period (1850-2005)

    NASA Astrophysics Data System (ADS)

    Prasanna, Venkatraman

    2016-04-01

    This paper evaluates the performance of 29 state-of-art CMIP5-coupled atmosphere-ocean general circulation models (AOGCM) in their representation of regional characteristics of monsoon simulation over South Asia. The AOGCMs, despite their relatively coarse resolution, have shown some reasonable skill in simulating the mean monsoon and precipitation variability over the South Asian monsoon region. However, considerable biases do exist with reference to the observed precipitation and also inter-model differences. The monsoon rainfall and surface flux bias with respect to the observations from the historical run for the period nominally from 1850 to 2005 are discussed in detail. Our results show that the coupled model simulations over South Asia exhibit large uncertainties from one model to the other. The analysis clearly brings out the presence of large systematic biases in coupled simulation of boreal summer precipitation, evaporation, and sea surface temperature (SST) in the Indian Ocean, often exceeding 50 % of the climatological values. Many of the biases are common to many models. Overall, the coupled models need further improvement in realistically portraying boreal summer monsoon over the South Asian monsoon region.

  9. Status of NCEP CFS vis-a-vis IPCC AR4 models for the simulation of Indian summer monsoon

    NASA Astrophysics Data System (ADS)

    Pokhrel, Samir; Dhakate, Ashish; Chaudhari, Hemantkumar S.; Saha, Subodh K.

    2013-01-01

    National Centers for Environmental Prediction (NCEP) Coupled Forecast System (CFS) is selected to play a lead role for monsoon research (seasonal prediction, extended range prediction, climate prediction, etc.) in the ambitious Monsoon Mission project of Government of India. Thus, as a prerequisite, a detail analysis for the performance of NCEP CFS vis-a-vis IPCC AR4 models for the simulation of Indian summer monsoon (ISM) is attempted. It is found that the mean monsoon simulations by CFS in its long run are at par with the IPCC models. The spatial distribution of rainfall in the realm of Indian subcontinent augurs the better results for CFS as compared with the IPCC models. The major drawback of CFS is the bifurcation of rain types; it shows almost 80-90 % rain as convective, contrary to the observation where it is only 50-65 %; however, the same lacuna creeps in other models of IPCC as well. The only respite is that it realistically simulates the proper ratio of convective and stratiform rain over central and southern part of India. In case of local air-sea interaction, it outperforms other models. However, for monsoon teleconnections, it competes with the better models of the IPCC. This study gives us the confidence that CFS can be very well utilized for monsoon studies and can be safely used for the future development for reliable prediction system of ISM.

  10. 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.

  11. 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.

  12. The Influence of Somalia and Oman Upwellings on the Indian Summer Monsoon

    NASA Astrophysics Data System (ADS)

    Izumo, T.; de Boyer Montégut, C.; Luo, J.; Behera, S. K.; Masson, S.; Yamagata, T.

    2006-12-01

    What controls the strength of the Indian summer monsoon is not well known yet. The Somalia and Oman upwellings peak during the summer monsoon and strongly cool the Sea Surface Temperature (SST) in the Western Arabian Sea. A slight change in their strength can thus have strong impacts on the SST and extent of the Indian ocean warm pool, which is the main source of moisture for the monsoon. Here the role of Somalia and Oman upwellings on the strength of the Indian monsoon is evidenced using both observations and the high resolution SINTEX-F Coupled Global Circulation Model (CGCM), which accurately simulates the monsoon. Within the CGCM, the spring increase and summer maximum of the Western Arabian Sea coastal upwellings are removed in a sensitivity experiment (SENS) by imposing over the Indian Ocean the mean windstress, instead of the temporally varying one of the control experiment (CTL). The ocean circulation becomes nearly stationnary. In summer, the main change in SST in SENS is a strong warming (up to 2°C) along the East African coast where coastal upwelling and off-shore horizontal advection of upwelled waters usually cool SST. This SST warming leads to a strong increase in the monsoon extent and strength along the West coast of India up to 5 mm/day (about 25% of CTL). The mechanism is as follow: in SENS, summer SST warming in the upwelling region causes anomalous evaporation, which increases specific humidity of the air masses going over the upwelling region. The humidity transport thus increases all over the Arabian sea towards the coastal Ghats mountains of India. This finally leads to enhanced moisture convergence and precipitations along the West coast of India. This role of coastal upwelling and associated SST variations on the Indian monsoon is confirmed by observations since 1980. Correlation analysis shows that enhanced summer precipitations on the West Indian coast are usually associated with warmer SST in summer East of Somalia-Oman and North

  13. Interaction of Convective Organization and Monsoon Precipitation, Atmosphere, Surface and Sea (INCOMPASS)

    NASA Astrophysics Data System (ADS)

    Turner, Andrew; Bhat, Gs; Evans, Jonathan; Marsham, John; Martin, Gill; Parker, Douglas; Taylor, Chris; Bhattacharya, Bimal; Madan, Ranju; Mitra, Ashis; Mrudula, Gm; Muddu, Sekhar; Pattnaik, Sandeep; Rajagopal, En; Tripathi, Sachida

    2015-04-01

    The monsoon supplies the majority of water in South Asia, making understanding and predicting its rainfall vital for the growing population and economy. However, modelling and forecasting the monsoon from days to the season ahead is limited by large model errors that develop quickly, with significant inter-model differences pointing to errors in physical parametrizations such as convection, the boundary layer and land surface. These errors persist into climate projections and many of these errors persist even when increasing resolution. At the same time, a lack of detailed observations is preventing a more thorough understanding of monsoon circulation and its interaction with the land surface: a process governed by the boundary layer and convective cloud dynamics. The INCOMPASS project will support and develop modelling capability in Indo-UK monsoon research, including test development of a new Met Office Unified Model 100m-resolution domain over India. The first UK detachment of the FAAM research aircraft to India, in combination with an intensive ground-based observation campaign, will gather new observations of the surface, boundary layer structure and atmospheric profiles to go with detailed information on the timing of monsoon rainfall. Observations will be focused on transects in the northern plains of India (covering a range of surface types from irrigated to rain-fed agriculture, and wet to dry climatic zones) and across the Western Ghats and rain shadow in southern India (including transitions from land to ocean and across orography). A pilot observational campaign is planned for summer 2015, with the main field campaign to take place during spring/summer 2016. This project will advance our ability to forecast the monsoon, through a programme of measurements and modelling that aims to capture the key surface-atmosphere feedback processes in models. The observational analysis will allow a unique and unprecedented characterization of monsoon processes that

  14. 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

  15. 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.

  16. Evaluation of Dynamics of the West African Monsoon Jump Simulated by the MIT Regional Climate Model

    NASA Astrophysics Data System (ADS)

    Eltahir, Elfatih A. B.; Im, Eun-Soon

    2015-04-01

    The seasonal advance and retreat of the West African monsoon behaves abrupt northward jump of maximum rainfall from the Guinean coast to the Sahel region. Both global and regional climate models have difficulties in accurately reproducing such a behavior due to its complexity combined the dynamical and physical processes. In this study, we evaluate the performance of the MIT Regional Climate Model (MRCM) in simulating the West African monsoon. For this, 20-year long-term simulation (1989-2008) is performed using the ERAInterim reanalysis as the initial and boundary condition, and the analysis primarily focuses on the dynamics associated with abrupt phase transitions of the monsoon rainfall. We first examine detailed characteristics in terms of the onset, maximum, and retreat of the monsoon rainfall using daily precipitation. We then present the dynamical explanation behind rainfall variability from the analysis of the absolute vorticity near the tropopause and the meridional gradient of boundary-layer entropy within the dynamical theory proposed by Eltahir and Gong (1996). Acknowledgements : This research was supported by the National Research Foundation Singapore through the Singapore MIT Alliance for Research and Technology's Center for Environmental Sensing and Modeling interdisciplinary research program.

  17. Holocene Monsoon Changes Inferred from Lake Sediment Pollen and Carbonate Records, Northeastern Cambodia

    NASA Astrophysics Data System (ADS)

    Maxwell, Andrew Lee

    2001-11-01

    Major Holocene monsoon changes in continental Southeast Asia are reconstructed from analysis of 14C-dated changes in pollen and organic/inorganic carbon in sediment cores taken from permanent, closed-basin, volcanic lakes in Ratanakiri Province, northeastern Cambodia. Analysis focuses on the nature and timing of monsoon changes, inferred from changes in vegetation and lake conditions. These data provide the first well-dated palynological record, covering most of the Holocene and continuous up to the present, from a terrestrial site in mainland Southeast Asia. The record from a 15-m core retrieved from Kara Lake, representing the last 9300 years, shows that the late Glacial conditions ended about 8500 14C yr B.P., more than 1000 years later than sites in southwest China. Summer monsoon intensity increased over the period ca. 8400-5300 14C yr B.P., similar to most other sites in the Asian monsoon region. A subsequent expansion of secondary forests at the expense of dense semievergreen forests suggest a drier climate leading to more frequent fire disturbance. After ca. 3500 14C yr B.P. disturbance frequency may have increased further with increasing seasonality. From ca. 2500 14C yr B.P. to the present, dense forest has recovered in a mosaic with annually burned dry forest, but climate may not be the main control on local vegetation dynamics in the late Holocene.

  18. [Tokophobia--a multidisciplinary problem].

    PubMed

    Billert, Hanna

    2007-10-01

    Pathological fear of childbirth known as "tokophobia" affects about 6-10% pregnancies and is of concern mainly because of remarkable sequele regarding women's morbidity, the neurobehavioral development of their children, and cesarean section on maternal request (CSMR). Fear of labor is a multidimensional problem involving a number of biological, psychological and social background factors and may be divided into primary and secondary tokophobia and tokophobia as a symptom of depression. Fear of childbirth is closely related to the fear of labor pain. It appears that women who experience fear, suffer from more pain due to alterations in the mechanisms of pregnancy induced analgesia. Despite no relevant connection between tokophobia and request for effective analgesia for labor pain relief, neuraxial techniques should always be available, especially to women with increased levels of negative emotions. However, epidural analgesia itself may increase fear level at the end and after labor and delivery. The mainstay of tokphobia treatment constitutes psychotherapeutic methods, which decrease negative labor experience; their impact on CSMR is controversial. There is a strong need for multidisciplinary approach to tokophobia due to its complexity and obstetric, anesthesiological, psychological and psychiatric implications.

  19. Submarine Landslides: A Multidisciplinary Crossroad

    NASA Astrophysics Data System (ADS)

    Moscardelli, L. G.

    2014-12-01

    The study of submarine landslides has advanced considerably in the last decade. A multitude of geoscience disciplines, including marine, petroleum and planetary geology, as well as geohazard assessments, are concerned with the study of these units. Oftentimes, researchers working in these fields disseminate their findings within their own communities and a multidisciplinary approach seems to lack. This presentation showcases several case studies in which a broader approach has increased our understanding of submarine landslides in a variety of geologic settings. Three-dimensional seismic data from several continental margins (Trinidad, Brazil, Morocco, Canada, GOM), as well as data from outcrop localities are shown to explore geomorphological complexities associated with submarine landslides. Discussion associated with the characterization and classification of submarine landslides is also part of this work. Topics that will be cover include: 1) how data from conventional oil and gas exploration activities can be used to increase our understanding of the dynamic behavior of submarine landslides, 2) analogies between terrestrial submarine landslides and potential Martian counterparts, 3) impact of submarine landslides in margin construction, as well as their economic significance and 4) the importance of quantifying the morphology of submarine landslides in a systematic fashion.

  20. 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

  1. 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.

  2. Tropospheric ozone variability during the monsoon season in Malaysia

    NASA Astrophysics Data System (ADS)

    Ahamad, Fatimah; Latif, Mohd Talib

    2013-11-01

    Vertical ozone (O3) profiles obtained from ozonesondes launched at Kuala Lumpur International Airport (KLIA), Malaysia were analyzed. Results of soundings between January to March 2011 and July to September 2011 are presented along with meteorological parameters (temperature and relative humidity (RH)). The overall O3 concentration range between the soundings made during the northeast monsoon (January - March) and the southwest monsoon (July - September) were not far from each other for altitudes below 8 km. However O3 variability is less pronounced between 2 km and 12 km during the southwest monsoon compared to the northeast monsoon season.

  3. Simulation of South-Asian Summer Monsoon in a GCM

    NASA Astrophysics Data System (ADS)

    Ajayamohan, R. S.

    2007-10-01

    Major characteristics of Indian summer monsoon climate are analyzed using simulations from the upgraded version of Florida State University Global Spectral Model (FSUGSM). The Indian monsoon has been studied in terms of mean precipitation and low-level and upper-level circulation patterns and compared with observations. In addition, the model's fidelity in simulating observed monsoon intraseasonal variability, interannual variability and teleconnection patterns is examined. The model is successful in simulating the major rainbelts over the Indian monsoon region. However, the model exhibits bias in simulating the precipitation bands over the South China Sea and the West Pacific region. Seasonal mean circulation patterns of low-level and upper-level winds are consistent with the model's precipitation pattern. Basic features like onset and peak phase of monsoon are realistically simulated. However, model simulation indicates an early withdrawal of monsoon. Northward propagation of rainbelts over the Indian continent is simulated fairly well, but the propagation is weak over the ocean. The model simulates the meridional dipole structure associated with the monsoon intraseasonal variability realistically. The model is unable to capture the observed interannual variability of monsoon and its teleconnection patterns. Estimate of potential predictability of the model reveals the dominating influence of internal variability over the Indian monsoon region.

  4. 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

  5. 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

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. Localized Pancreatic Cancer: Multidisciplinary Management.

    PubMed

    Coveler, Andrew L; Herman, Joseph M; Simeone, Diane M; Chiorean, E Gabriela

    2016-01-01

    Pancreatic cancer is an aggressive cancer that continues to have single-digit 5-year mortality rates despite advancements in the field. Surgery remains the only curative treatment; however, most patients present with late-stage disease deemed unresectable, either due to extensive local vascular involvement or the presence of distant metastasis. Resection guidelines that include a borderline resectable group, as well as advancements in neoadjuvant chemotherapy and radiation that improve resectability of locally advanced disease, may improve outcomes for patients with more invasive disease. Multi-agent chemotherapy regimens fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) and nab-paclitaxel with gemcitabine improved response rates and survival in metastatic pancreatic cancer and are now being used in earlier stages for patients with localized potentially resectable and unresectable disease, with goals of downstaging tumors to allow margin-negative resection and reducing systemic recurrence. Chemoradiotherapy, although still controversial for both resectable and unresectable pancreatic cancer, is being used in the context of contemporary chemotherapy backbone regimens, and novel radiation techniques such as stereotactic body frame radiation therapy (SBRT) are studied on the premise of maintaining or improving efficacy and reducing treatment duration. Patient selection for optimal treatment designation is currently provided by multidisciplinary tumor boards, but biomarker discovery, in blood, tumors, or through novel imaging, is an area of intense research. Results to date suggest that some patients with unresectable disease at the outset have survival rates as good as those with initially resectable disease if able to undergo surgical resection. Long-term follow-up and improved clinical trials options are needed to determine optimal treatment modalities for patients with localized pancreatic cancer. PMID:27249726

  11. 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.

  12. 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.

  13. The Indian summer monsoon rainfall: interplay of coupled dynamics, radiation and cloud microphysics

    NASA Astrophysics Data System (ADS)

    Patra, P. K.; Behera, S. K.; Herman, J. R.; Maksyutov, S.; Akimoto, H.; Yamagata, T.

    2005-05-01

    The Indian summer monsoon rainfall (ISMR), which has a strong connection to agricultural food production, has been less predictable by conventional models in recent times. Two distinct years 2002 and 2003 with lower and higher July rainfall, respectively, are selected to help understand the natural and anthropogenic influences on ISMR. We show that heating gradients along the meridional monsoon circulation are reduced due to aerosol radiative forcing and the Indian Ocean Dipole in 2002. An increase in the dust and biomass-burning component of the aerosols through the zonal monsoon circulation resulted in reduction of cloud droplet growth in July 2002. These conditions were opposite to those in July 2003 which led to an above average ISMR. In this study, we have utilized NCEP/NCAR reanalyses for meteorological data (e.g. sea-surface temperature, horizontal winds, and precipitable water), NOAA interpolated outgoing long-wave radiation, IITM constructed all-India rainfall amounts, aerosol parameters as observed from the TOMS and MODIS satellites, and ATSR fire count maps. Based on this analysis, we suggest that monsoon rainfall prediction models should include synoptic as well as interannual variability in both atmospheric dynamics and chemical composition.

  14. The Indian summer monsoon rainfall: interplay of coupled dynamics, radiation and cloud microphysics

    NASA Astrophysics Data System (ADS)

    Patra, P. K.; Behera, S. K.; Herman, J. R.; Maksyutov, S.; Akimoto, H.; Yamagata, Y.

    2005-08-01

    The Indian summer monsoon rainfall (ISMR), which has a strong connection to agricultural food production, has been less predictable by conventional models in recent times. Two distinct years 2002 and 2003 with lower and higher July rainfall, respectively, are selected to help understand the natural and anthropogenic influences on ISMR. We show that heating gradients along the meridional monsoon circulation are reduced due to aerosol radiative forcing and the Indian Ocean Dipole in 2002. An increase in the dust and biomass-burning component of the aerosols through the zonal monsoon circulation resulted in reduction of cloud droplet growth in July 2002. These conditions were opposite to those in July 2003 which led to an above average ISMR. In this study, we have utilized NCEP/NCAR reanalyses for meteorological data (e.g. sea-surface temperature, horizontal winds, and precipitable water), NOAA interpolated outgoing long-wave radiation, IITM constructed all-India rainfall amounts, aerosol parameters as observed from the TOMS and MODIS satellites, and ATSR fire count maps. Based on this analysis, we suggest that monsoon rainfall prediction models should include synoptic as well as interannual variability in both atmospheric dynamics and chemical composition.

  15. Studies on MODIS NDVI and its relation with the south west monsoon, western ghats, India

    NASA Astrophysics Data System (ADS)

    Lakshmi Kumar, Tv; Barbosa, Humberto; Uma, R.; Rao, Koteswara

    2012-07-01

    Eleven years (2000 to 2010) of Normalized Difference Vegetation Index (NDVI) data, derived from Moderate Imaging Spectroradiometer (MODIS) Terra with 250m resolution are used in the present study to discuss the changes in the trends of vegetal cover. The interannual variability of NDVI over western ghats (number of test sites are 17) showed increasing trend and the pronounced changes are resulted due to the monsoon variability in terms of its distribution (wide spread/fairly wide spread/scattered/isolated) and activity (vigorous/normal/weak) and are studied in detail. The NDVI progression is observed from June with a minimum value of 0.179 and yielded to maximum at 0.565 during September/October, on average. The study then relates the NDVI with the no of light, moderate and heavy rainfall events via statistical techniques such as correlation and regression to understand the connection in between the ground vegetation and the south west monsoon. The results of the study inferred i) NDVI, Antecedent Precipitation Index (API) are in good agreement throughout the monsoon which is evidenced by correlation as well as by Morlett Wavelet Analysis, ii) NDVI maintained good correlation with no of Light Rainy and Moderate Rainy alternatively but not with no of Heavy Rainy days, iii) Relation of NDVI with Isolated, Scattered distributions and active monsoons is substantial and iv) Phenological stages captured the Rate of Green Up during the crop season over western ghats.

  16. 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.

  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

    2015-12-01

    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. Direct radiative effects of anthropogenic aerosols on Indian summer monsoon circulation

    NASA Astrophysics Data System (ADS)

    Das, Sushant; Dey, Sagnik; Dash, S. K.

    2016-05-01

    The direct radiative impacts of anthropogenic aerosols on the dynamics of Indian summer monsoon circulation are examined using the regional climate model version 4.1 (RegCM4.1). High anthropogenic aerosol optical depth (AAOD >0.1) and surface shortwave cooling (<-6 W m-2) are simulated over the Indo-Gangetic Basin (IGB), northeast India, east coast of India, and its outflow to the Bay of Bengal (BoB) during the monsoon season (June to September) in the period 2001 to 2010. The analysis reveals a decrease in near surface air temperature at 2 m over the IGB and east coast of India by >0.2 °C due to the dimming effect of anthropogenic aerosols. The aerosol-induced cooling leads to an increase in surface pressure over the local hotspots in the Indian landmass, which reduces the land-sea pressure contrast resulting in weakening of summer monsoon circulation. The simulated surface pressure anomaly also inhibits moisture transport from the BoB towards Indian landmass thereby enhancing precipitation over the BoB and parts of the east coast of India. The impacts are interpreted as conservative estimates because of the underestimation of AAOD by the model due to uncertainties in emission inventory and biases in simulated meteorology. Our results demonstrate the direct radiative impacts of anthropogenic aerosols on the Indian monsoon circulation and call for future studies combining the dynamical and microphysical impacts, which are not considered in this study.

  19. Atmospheric polycyclic aromatic hydrocarbons (PAHs) of southern Taiwan in relation to monsoons.

    PubMed

    Cheng, Jing-O; Ko, Fung-Chi; Lee, Chon-Lin; Fang, Meng-Der

    2016-08-01

    The concentrations and gas-particle partitioning of atmospheric polycyclic aromatic hydrocarbons (PAHs) were intensively measured in the Hengchun Peninsula of southern Taiwan. The concentrations of total PAH (Σ38PAH), including gas and particle phases, ranged from 0.85 to 4.40 ng m(-3). No significant differences in the PAH levels and patterns were found between the samples taken at day and at night. The gas phase PAH concentrations were constant year-round, but the highest levels of particle-associated PAHs were found during the northeast monsoon season. Long-range transport and rainfall scavenging mechanisms contributed to the elevated levels in aerosols andΣ38PAH concentrations. Results from principal component analysis (PCA) indicated that the major sources of PAHs in this study were vehicular emissions. The back trajectories demonstrated that air mass movement driven by the monsoon system was the main influence on atmospheric PAH profiles and concentrations in the rural region of southern Taiwan. Gas-particle partition coefficients (K p ) of PAHs were well-correlated with sub-cooled liquid vapor pressures (P (o) L ) and demonstrated significant seasonal variation between the northeast (NE) and the southwest (SW) monsoon seasons. This study sheds light on the role of Asian monsoons regarding the atmospheric transport of PAHs. PMID:27137192

  20. Indian summer monsoon precipitating clouds: role of microphysical process rates

    NASA Astrophysics Data System (ADS)

    Hazra, Anupam; Chaudhari, Hemantkumar S.; Pokhrel, Samir; Saha, Subodh K.

    2016-04-01

    The budget analysis of microphysical process rates based on Modern Era Retrospective-analysis for Research and Applications (MERRA) products are presented in the study. The relative importance of different microphysical process rates, which is crucial for GCMs, is investigated. The autoconversion and accretion processes are found to be vital for Indian Summer Monsoon (ISM). The map-to-map correlations are examined between observed precipitation and MERRA reanalysis. The pattern correlations connote the fidelity of the MERRA datasets used here. Results of other microphysical parameters (e.g. ice water content from CloudSat, high cloud fraction from CALIPSO and MODIS, latent heating from TRMM, cloud ice mixing ratio from MERRA) are presented in this study. The tropospheric temperature from reanalysis product of MERRA and NCEP are also analyzed. Furthermore, the linkages between cloud microphysics production rates and dynamics, which are important for North-South tropospheric temperature gradient for maintaining the ISM circulation, are also discussed. The study demonstrates the microphysical process rates, which are actually responsible for the cloud hydrometeors and precipitation formation on the monsoon intraseasonal oscillations timescale. Cloud to rain water auto-conversion and snow accretion rates are the dominant processes followed by the rain accretion. All these tendency terms replicates the similar spatial patterns as that of precipitation. The quantification of microphysical process rates and precipitation over different regions are shown here. The freezing rate is also imperative for the formation of cloud ice as revealed by the observation. Freezing rates at upper level and snow accretion at middle level may have effect on latent heating release. Further it can modulate the north-south temperature gradient which can influence the large-scale monsoon dynamics. The rain water evaporation is also considered as a key aspect for controlling the low level

  1. 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

  2. Distribution and sources of particulate organic matter in the Indian monsoonal estuaries during monsoon

    NASA Astrophysics Data System (ADS)

    Sarma, V. V. S. S.; Krishna, M. S.; Prasad, V. R.; Kumar, B. S. K.; Naidu, S. A.; Rao, G. D.; Viswanadham, R.; Sridevi, T.; Kumar, P. P.; Reddy, N. P. C.

    2014-11-01

    The distribution and sources of particulate organic carbon (POC) and nitrogen (PN) in 27 Indian estuaries were examined during the monsoon using the content and isotopic composition of carbon and nitrogen. Higher phytoplankton biomass was noticed in estuaries with deeper photic zone than other estuaries receiving higher suspended matter. The δ13CPOC and δ15NPN data suggest that relatively higher δ13CPOC (-27.9 to -22.6‰) and lower δ15NPN (0.7 to 5.8‰) were noticed in the estuaries located in the northern India, north of 16°N, and lower δ13CPOC (-31.4 to -28.2‰) and higher δ15NPN (5 to 10.3‰) in the estuaries located in the southern India. This is associated with higher Chl a in the northern than southern estuaries suggesting that in situ production contributed significantly to the POC pool in the former, whereas terrestrial sources are important in the latter estuaries. The spatial distribution pattern of δ15NPN is consistent with fertilizer consumption in the Indian subcontinent, which is twice as much in the northern India as in the south whereas δ13CPOC suggests that in situ production is a dominant source in the southern and terrestrial sources are important in the northern estuaries. Based on the Stable Isotope Analysis in R model, 40-90% (70-90%) of organic matter is contributed by C3 plants (freshwater algae) in the estuaries located in the northern (southern) India.

  3. 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

  4. 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

  5. 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.

  6. Multi-disciplinary optimization of aeroservoelastic systems

    NASA Technical Reports Server (NTRS)

    Karpel, Mardechay

    1992-01-01

    The purpose of the research project was to continue the development of new methods for efficient aeroservoelastic analysis and optimization. The main targets were as follows: to complete the development of analytical tools for the investigation of flutter with large stiffness changes; to continue the work on efficient continuous gust response and sensitivity derivatives; and to advance the techniques of calculating dynamic loads with control and unsteady aerodynamic effects. An efficient and highly accurate mathematical model for time-domain analysis of flutter during which large structural changes occur was developed in cooperation with Carol D. Wieseman of NASA LaRC. The model was based on the second-year work 'Modal Coordinates for Aeroelastic Analysis with Large Local Structural Variations'. The work on continuous gust response was completed. An abstract of the paper 'Continuous Gust Response and Sensitivity Derivatives Using State-Space Models' was submitted for presentation in the 33rd Israel Annual Conference on Aviation and Astronautics, Feb. 1993. The abstract is given in Appendix A. The work extends the optimization model to deal with continuous gust objectives in a way that facilitates their inclusion in the efficient multi-disciplinary optimization scheme. Currently under development is a work designed to extend the analysis and optimization capabilities to loads and stress considerations. The work is on aircraft dynamic loads in response to impulsive and non-impulsive excitation. The work extends the formulations of the mode-displacement and summation-of-forces methods to include modes with significant local distortions, and load modes. An abstract of the paper,'Structural Dynamic Loads in Response to Impulsive Excitation' is given in appendix B. Another work performed this year under the Grant was 'Size-Reduction Techniques for the Determination of Efficient Aeroservoelastic Models' given in Appendix C.

  7. 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

  8. 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

    2015-01-01

    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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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.

  14. New statistical models for long-range forecasting of southwest monsoon rainfall over India

    NASA Astrophysics Data System (ADS)

    Rajeevan, M.; Pai, D. S.; Anil Kumar, R.; Lal, B.

    2007-06-01

    The India Meteorological Department (IMD) has been issuing long-range forecasts (LRF) based on statistical methods for the southwest monsoon rainfall over India (ISMR) for more than 100 years. Many statistical and dynamical models including the operational models of IMD failed to predict the recent deficient monsoon years of 2002 and 2004. In this paper, we report the improved results of new experimental statistical models developed for LRF of southwest monsoon seasonal (June September) rainfall. These models were developed to facilitate the IMD’s present two-stage operational forecast strategy. Models based on the ensemble multiple linear regression (EMR) and projection pursuit regression (PPR) techniques were developed to forecast the ISMR. These models used new methods of predictor selection and model development. After carrying out a detailed analysis of various global climate data sets; two predictor sets, each consisting of six predictors were selected. Our model performance was evaluated for the period from 1981 to 2004 by sliding the model training period with a window length of 23 years. The new models showed better performance in their hindcast, compared to the model based on climatology. The Heidke scores for the three category forecasts during the verification period by the first stage models based on EMR and PPR methods were 0.5 and 0.44, respectively, and those of June models were 0.63 and 0.38, respectively. Root mean square error of these models during the verification period (1981 2004) varied between 4.56 and 6.75% from long period average (LPA) as against 10.0% from the LPA of the model based on climatology alone. These models were able to provide correct forecasts of the recent two deficient monsoon rainfall events (2002 and 2004). The experimental forecasts for the 2005 southwest monsoon season based on these models were also found to be accurate.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Annual monsoon rains recorded by Jurassic dunes.

    PubMed

    Loope, D B; Rowe, C M; Joeckel, R M

    2001-07-01

    Pangaea, the largest landmass in the Earth's history, was nearly bisected by the Equator during the late Palaeozoic and early Mesozoic eras. Modelling experiments and stratigraphic studies have suggested that the supercontinent generated a monsoonal atmospheric circulation that led to extreme seasonality, but direct evidence for annual rainfall periodicity has been lacking. In the Mesozoic era, about 190 million years ago, thick deposits of wind-blown sand accumulated in dunes of a vast, low-latitude desert at Pangaea's western margin. These deposits are now situated in the southwestern USA. Here we analyse slump masses in the annual depositional cycles within these deposits, which have been described for some outcrops of the Navajo Sandstone. Twenty-four slumps, which were generated by heavy rainfall, appear within one interval representing 36 years of dune migration. We interpret the positions of 20 of these masses to indicate slumping during summer monsoon rains, with the other four having been the result of winter storms. The slumped lee faces of these Jurassic dunes therefore represent a prehistoric record of yearly rain events.

  2. 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.

  3. 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

  4. 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.

  5. 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 is investigating frameworks for supporting multidisciplinary analysis and optimization research. 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. This year, the MDO Branch has gained experience with the iSIGHT framework. This paper describes experiences with four aerospace applications, including: (1) reusable launch vehicle sizing, (2) aerospike nozzle design, (3) low-noise rotorcraft trajectories, and (4) acoustic liner design. Brief overviews of each problem are provided, including the number and type of disciplinary codes and computation time estimates. In addition, the optimization methods, objective functions, design variables, and constraints are described for each problem. For each case, discussions on the advantages and disadvantages of using the iSIGHT framework are provided as well as notes on the ease of use of various advanced features and suggestions for areas of improvement.

  6. Three exceptionally strong East-Asian summer monsoon events during glacial times in the past 470 kyr

    NASA Astrophysics Data System (ADS)

    Rousseau, D.-D.; Wu, N.; Pei, Y.; Li, F.

    2009-04-01

    Chinese loess sequences are interpreted as a reliable record of the past variation of the East Asian monsoon regime through the alternation of loess and paleosols units, dominated by the winter and summer monsoon, respectively. Different proxies have been used to describe this system, mostly geophysical, geochemical or sedimentological. Terrestrial mollusks are also a reliable proxy of past environmental conditions and are often preserved in large numbers in loess deposits. The analysis of the mollusk remains in the Luochuan sequence, comprising L5 loess to S0 soil, i.e. the last 500 ka, shows that for almost all identified species, the abundance is higher at the base of the interval (L5 to L4) than in the younger deposits. Using the present ecological requirements of the identified mollusk species in the Luochuan sequence allows the definition of two main mollusk groups varying during the last 500 kyr. The cold-aridiphilous individuals indicate the so-called Asian winter monsoon regime and predominantly occur during glacials, when dust is deposited. The thermal-humidiphilous mollusks are prevalent during interglacial or interstadial conditions of the Asian summer monsoon, when soil formation takes place. In the sequence, three events with exceptionally high abundance of the Asian summer monsoon indicators are recorded during the L5, L4 and L2 glacial intervals, i.e., at about 470, 360 and 170 kyr, respectively. The L5 and L4 events appear to be the strongest (high counts). Similar variations have also been identified in the Xifeng sequence, distant enough from Luochuan, but also in Lake Baikal further North, to suggest that this phenomenon is regional rather than local. The indicators of the summer monsoon within the glacial intervals imply a strengthened East-Asian monsoon interpreted as corresponding to marine isotope stages 12, 10 and 6, respectively. The L5 and L2 summer monsoons are coeval with Mediterranean sapropels S12 and S6, which characterize a strong

  7. Three exceptionally strong East-Asian summer monsoon events during glacial conditions in the past 470 kyr

    NASA Astrophysics Data System (ADS)

    Rousseau, D.-D.; Wu, N.; Pei, Y.; Li, F.

    2008-12-01

    Chinese loess sequences are interpreted as a reliable record of the past variation of the East Asian monsoon regime through the alternation of loess and paleosols units, dominated by the winter and summer monsoon, respectively. Different proxies have been used to describe this system, mostly geophysical, geochemical or sedimentological. Terrestrial mollusks are also a reliable proxy of past environmental conditions and are often preserved in large numbers in loess deposits. The analysis of the mollusk remains in the Luochuan sequence, comprising L5 loess to S0 soil, i.e. the last 500 ka, shows that for almost all identified species, the abundance is higher at the base of the interval (L5 to L4) than in the younger deposits. Using the present ecological requirements of the identified mollusk species in the Luochuan sequence allows the definition of two main mollusk groups varying during the last 500 kyr. The cold-aridiphilous individuals indicate the so-called Asian winter monsoon regime and predominantly occur during glacials, when dust is deposited. The thermal-humidiphilous mollusks are prevalent during interglacial or interstadial conditions of the Asian summer monsoon, when soil formation takes place. In the sequence, three events with exceptionally high abundance of the Asian summer monsoon indicators are recorded during the L5, L4 and L2 glacial intervals, i.e., at about 470, 360 and 170 kyr, respectively. The L5 and L4 events appear to be the strongest (high counts). Similar variations have also been identified in the Xifeng sequence, distant enough from Luochuan, but also in Lake Baikal further North, to suggest that this phenomenon is regional rather than local. The indicators of the summer monsoon within the glacial intervals imply a strengthened East-Asian monsoon interpreted as corresponding to marine isotope stages 6, 10 and 12, respectively. The L5 and L2 summer monsoons are coeval with Mediterranean sapropels S12 and S6, which characterize a strong

  8. 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.

  9. 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.

  10. 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.

  11. Multidisciplinary management for esophageal and gastric cancer.

    PubMed

    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.

  12. 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

  13. Impacts of East Asian aerosols on the Asian monsoon

    NASA Astrophysics Data System (ADS)

    Bartlett, Rachel; Bollasina, Massimo; Booth, Ben; Dunstone, Nick; Marenco, Franco

    2016-04-01

    Over recent decades, aerosol emissions from Asia have increased rapidly. Aerosols are able to alter radiative forcing and regional hydroclimate through direct and indirect effects. Large emissions within the geographical region of the Asian monsoon have been found to impact upon this vital system and have been linked to observed drying trends. The interconnected nature of smaller regional monsoon components (e.g. the Indian monsoon and East Asian monsoon) presents the possibility that aerosol sources could have far-reaching impacts. Future aerosol emissions are uncertain and may continue to dominate regional impacts on the Asian monsoon. Standard IPCC future emissions scenarios do not take a broad sample of possible aerosol pathways. We investigate the sensitivity of the Asian monsoon to East Asian aerosol emissions. Experiments carried out with HadGEM2-ES use three time-evolving future anthropogenic aerosol emissions scenarios with similar time-evolving greenhouse gases. We find a wetter summer over southern China and the Indochina Peninsula associated with increased sulfate aerosol over China. The southern-flood-northern-drought pattern seen in observations is reflected in these results. India is found to be drier in the summer overall, although wetter in June. These precipitation changes are linked to the increase in sulfate through the alteration of large scale dynamics. Sub-seasonal changes are also seen, with an earlier withdrawal of the monsoon over East Asia.

  14. 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.

  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. Extracting the vegetation phenology of tropical monsoon forest

    NASA Astrophysics Data System (ADS)

    Shang, R.; Xu, M.; Zuo, L.

    2015-12-01

    The monsoon forests cover over 40% of tropical forests, and play a significant role in terrestrial ecosystem carbon exchange and water-use efficiency of tropical ecosystems. The monsoons are changing under the global changes, and then impact the vegetation growth. However, the vegetation phenology in this area are difficult to describe, where the "V"-shaped seasonal growth trajectories of tropical monsoon forests are totally different from the normal seasonal trajectories such as the boreal forests. In this paper, a "V"-shaped curve is proposed to simulate the "V"-shaped seasonal trajectory. Current extractions of the onset of greenness are not suitable for "V"-shaped seasonal trajectory, which are seriously affected by the gaps in the rapid growth stage due to the heavy rain. For its insensitivity to the gaps or noise, the whole "V"-shaped curve was used to determine the phenology of tropical monsoon forest, and the lowest point in "V"-shaped curve was regarded as the phenology. The extracted phenology was showed to be correlated with the precipitation, and the validations with ground observations demonstrated that this new methodology has the ability to extract the phenology of tropical monsoon forest correctly. These phenology maps of tropical monsoon forest assist to understand the impact of climate changes in the monsoon regions.

  17. The North American Monsoon Forecast Forum at CPC/NCEP

    NASA Astrophysics Data System (ADS)

    Schemm, J. E.; Higgins, W.; Long, L.; Shi, W.; Gochis, D. J.

    2009-12-01

    In 2008, CPC introduced a new operational product to provide users a forum to monitor the North American monsoon (NAM). The NAME Forecast Forum (NAME FF) was proposed and endorsed by the North American Monsoon Experiment (NAME) Project Science Working Group as a natural extension to the NAME modeling activities coordinated under the NAME Climate Process Team project. It provided an opportunity to consolidate and assess, in real-time, the skill of intra-seasonal and seasonal monsoon forecasts. The NAME FF has continued in 2009 and three modeling groups collaborate with CPC to provide model simulated seasonal precipitation forecasts in the monsoon region. The website includes spatial maps and accumulated precipitation area-averaged over eight sub-regions of the NAM domain and is updated daily to include the current observed precipitation. A weekly update of the current conditions of the NAM system has been added to CPC’s American Monsoons monitoring webpage at, http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/American_Monsoons/NAME/index.shtml. A highlight for the 2009 season is the inclusion of the NCEP CFS forecasts in T382 horizontal resolution. These special high-resolution runs were made with initial conditions in mid-April to accommodate the CPC’s hurricane season outlook. Some results based on the T382 CFS runs also will be presented with emphasis on the prediction of precipitation and accompanying atmospheric circulation over the NAM region.

  18. 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.

  19. Predictability of global monsoon rainfall in NCEP CFSv2

    NASA Astrophysics Data System (ADS)

    Saha, Subodh Kumar; Sujith, K.; Pokhrel, Samir; Chaudhari, Hemantkumar S.; Hazra, Anupam

    2016-09-01

    This study evaluates the actual and potential prediction skill of the global monsoon rainfall using hindcast simulations by NCEP CFSv2 at zero to three lead forecast months (L0-L3). It is shown that the model has moderate skill in global monsoon rainfall (GMR) prediction, where the boreal summer monsoon rainfall forecast is more skillful than that of the austral summer. In general, the prediction skill of the GMR (actual and potential) increases with the decrease in lead forecast time, which is true for the all major regional monsoons, except the Australian monsoon. Over the Australian monsoon region, both actual and potential prediction skills in rainfall increase with increase in lead forecast. The forecast skill of tropical SST during austral summer is a maximum at 3 months lead forecast (i.e. July initial conditions) and that is associated with spring predictability barrier. Using partial least square (PLS) regression method, it is shown that the major predictor (first latent vector) of the boreal and austral summer monsoon rainfall variability is ENSO, and the influence of ENSO on rainfall variability is much stronger in the model as compared to the observation. The second PLS regression mode is associated with the non-ENSO variability like tropical Atlantic, Indian, subtropical northwest Pacific Ocean variability, midlatitude interactions etc. However, the model has very poor skill in reproducing the second mode, particularly during the boreal summer monsoon season. It is also shown that a significant part of the Indian summer monsoon rainfall variability is controlled by other than ENSO variability and the model has limited success in capturing that.

  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. 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)

  2. Recent trends and tele-connections among South and East Asian summer monsoons in a warming environment

    NASA Astrophysics Data System (ADS)

    Preethi, B.; Mujumdar, M.; Kripalani, R. H.; Prabhu, Amita; Krishnan, R.

    2016-06-01

    Recent trends, variations and tele-connections between the two large regional sub-systems over the Asian domain, the South Asian and the East Asian monsoons are explored using data for the 1901-2014 period. Based on trend analysis a dipole-type configuration with north-drought and south-flood over South as well as East Asia is observed. Two regions over South Asia, one exhibiting a significant decreasing trend in summer monsoon rainfall over northeast India and the other significant increasing trend over the northern parts of the west coast of India are identified. Similarly two regions over East Asia, one over South Korea-southern parts of Japan and the other over South China are also identified both indicating a significant increasing trend in the summer monsoon rainfall. These trends are examined post 1970s. Possible factors associated with the recent trends are explored. Analysis of sea surface temperature (SST), mean sea level pressure and winds at lower troposphere indicates that the entire monsoon flow system appears to have shifted westwards, with the monsoon trough over South Asia indicating a westward shift by about 2-3° longitudes and the North Pacific Subtropical High over East Asia seems to have shifted by about 5-7° longitudes. These shifts are consistent with the recent rainfall trends. Furthermore, while the West Indian Ocean SSTs appear to be related with the summer monsoon rainfall over northern parts of India and over North China, the West Pacific SSTs appear to be related with the rainfall over southern parts of India and over South Korea- southern Japan sector.

  3. MONSOON: Image Acquisition System or "Pixel Server"

    NASA Astrophysics Data System (ADS)

    Starr, Barry M.; Buchholz, Nick C.; Rahmer, Gustavo; Penegor, Gerald; Schmidt, Ricardo E.; Warner, Michael; Merrill, Michael; Claver, Charles F.; Ho, Y.; Chopra, K. N.; Shroff, C.; Shroff, D.

    2003-03-01

    The MONSOON Image Acquisition System has been designed to meet the need for scalable, multichannel, high-speed image acquisition required for the next-generation optical and infared detectors and mosaic projects currently under development at NOAO as described in other papers at this proceeding such as ORION, NEWFIRM, QUOTA, ODI and LSST. These new systems with their large scale (64 to 2000 channels) and high performance (up to 1Gbyte/s) raise new challenges in terms of communication bandwidth, data storage and data processing requirements which are not adequately met by existing astronomical controllers. In order to meet this demand, new techniques for not only a new detector controller, but rather a new image acquisition architecture, have been defined. These extremely large scale imaging systems also raise less obvious concerns in previously neglected areas of controller design such as physical size and form factor issues, power dissipation and cooling near the telescope, system assembly/test/ integration time, reliability, and total cost of ownership. At NOAO we have taken efforts to look outside of the astronomical community for solutions found in other disciplines to similar classes of problems. A large number of the challenges raised by these system needs are already successfully being faced in other areas such as telecommunications, instrumentation and aerospace. Efforts have also been made to use true commercial off the shelf (COTS) system elements, and find truly technology independent solutions for a number of system design issues whenever possible. The Monsoon effort is a full-disclosure development effort by NOAO in collaboration with the CARA ASTEROID project for the benefit of the astronomical community.

  4. 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

  5. A predictive monsoon signal in the surface level thermal field over India

    NASA Technical Reports Server (NTRS)

    Mooley, D. A.; Paolino, D. A.

    1988-01-01

    The mean monthly surface thermal field over India during the premonsoon months March-May, based on mean monthly-temperature/minimum-temperature/maximum-temperature data from the network of 119 stations, was examined with the objective of locating significant predictor parameters for forecasting Indian monsoon rainfall. The results of linear correlation analysis bring out three areas for which the relationships between Indian monsoon rainfalls and the area average of mean monthly minimum temperature for April or for May were found to be significant. The best correlation was found for the southern peninsular area, where the mean May minimum temperature is significantly related to the 500 mB April ridge, a tendency in the Southern Oscillation Index, and a tendency in eastern equatorial Pacific SST.

  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. Man and Environment, A Multidisciplinary Teachers Guide.

    ERIC Educational Resources Information Center

    Martin, F. H.; And Others

    This multidisciplinary guide, developed for teachers in the secondary schools, stresses the use of Man and Environment in Arkansas. The guide illustrates how teachers in social studies, the arts, English, science, physical education and health, home economics, and mathematics can implement these materials into their present classroom situations. A…

  8. 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…

  9. 34 CFR 303.17 - Multidisciplinary.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Multidisciplinary. 303.17 Section 303.17 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION EARLY INTERVENTION PROGRAM FOR INFANTS AND TODDLERS...

  10. 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.

  11. 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.

  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. Placenta accreta and anesthesia: A multidisciplinary approach

    PubMed Central

    Khokhar, RS; Baaj, J; Khan, MU; Dammas, FA; Rashid, N

    2016-01-01

    Placenta accreta (an abnormally adherent placenta) is one of the two leading causes of peripartum hemorrhage and the most common indication for peripartum hysterectomy. Placenta accreta may be associated with significant maternal hemorrhage at delivery owing to the incomplete placental separation. When placenta accreta is diagnosed before delivery, a multidisciplinary approach may improve patient outcome. PMID:27375391

  14. 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…

  15. 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…

  16. Multidisciplinary workshops: learning to work together.

    PubMed

    Fatchett, Anita; Taylor, Dawn

    2013-03-01

    Health and social care professional practice needs to move with the times and to respond to the ever-changing combination of health needs, economic realities and health-policy imperatives. A clear understanding of the variety of forces at play and the ability to marshal these to good effect by working in partnership with multidisciplinary colleagues and children/families is a must, not least in this time of economic austerity and ever-rising health inequalities, when vulnerable children's lives and complex family relationships and behaviours so easily become increasingly strained and challenged. This sad reality calls out for relevant joined-up solutions by all participants--an agenda so often called into question by court judgement after court judgement. The multidisciplinary workshops to be discussed have developed and changed over the past decade and provide a safe but realistic learning environment for students from health and social care backgrounds to experience the difficulties and barriers to good multidisciplinary working, to better understand others' perspectives and activities and consider and develop new and better practical strategies for working with multidisciplinary professional colleagues, children and families. All of the workshops are underpinned by specific discipline-focused theoretical work.

  17. The Dominant Synoptic-Scale Modes of North American Monsoon Precipitation

    NASA Astrophysics Data System (ADS)

    Serra, Y. L.; Seastrand, S.; Castro, C. L.; Ritchie, E.

    2014-12-01

    In this study we explore the mechanisms of synoptic rainfall variability using observations from the Tropical Rainfall Measuring Mission satellite. While previously shown to have an important impact on North American monsoon rainfall, tropical cyclones are excluded from this analysis, in order to focus on more frequent synoptic disturbances within the region. A rotated empirical orthogonal function analysis of North American monsoon rainfall for June through September 2002-2009 suggests low-level tropical disturbances contribute to the leading two modes of precipitation variability within this region. The low-level disturbances result in gulf surges, or low-level surges of moisture up the Gulf of California, and provide a key low-level moisture source to facilitate development of organized convection. In the first mode the low-level trough brings precipitation to lower elevations along the western slopes of the Sierra Madre Occidental south of Hermosillo, Mexico and over the southern Baja Peninsula. In the second mode the low-level trough interacts with an upper-level inverted trough enhancing precipitation into the southwestern United States and northwest Mexico. In particular, the upper-level trough contributes to the easterly-northeasterly shear across the region, favoring mesoscale convective organization and enhanced deep convection over the Sierra Madre Occidental and higher elevations in southeast Arizona. The EOF methodology offers an objective approach for determining the dominant modes of precipitation for the monsoon region useful for identifying past and monitoring future low-frequency impacts on these modes.

  18. 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.

  19. 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.

  20. On the dynamical basis for the Asian summer monsoon rainfall-El Nino relationship

    SciTech Connect

    Nigam, S.

    1994-11-01

    The dynamical basis for the Asian summer monsoon rainfall-El Nino linkage is explored through diagnostic calculations with a linear steady-state multilayer primitive equation model. The contrasting monsoon circulation during recent El Nino (1987) and La Nina (1988) years is first simulated using orography and the residually diagnosed heating (from the thermodynamic equation and the uninitialized, but mass-balanced, ECMWF analysis) as forcings, and then analyzed to provide insight into the importance of various regional forcings, such as the El Nino-related heating anomalies over the tropical Indian and Pacific Oceans. The striking simulation of the June-August (1987-1988) near-surface and upper-air tropical circulation anomalies indicates that tropical anomaly dynamics during northern summer is essentially linear even at the 150-mb level. The vertical structure of the residually diagnosed heating anomaly that contributes to this striking simulation differs significantly from the specified canonical vertical structure (used in generating 3D heating from OLR/precipitation distributions) near the tropical tropopause. The dynamical diagnostic analysis of the anomalous circulation during 1987 and 1988 March-May and June-August periods shows the orographically forced circulation anomaly (due to changes in the zonally averaged basic-state flow) to be quite dominant in modulating the low-level moisture-flux convergence and hence monsoon rainfall over Indochina. The El Nino-related persistent (spring-to-summer) heating anomalies over the tropical Pacific and Indian Ocean basins, on the other hand, mostly regulate the low-level westerly monsoon flow intensity over equatorial Africa and the northern Indian Ocean and, thereby, the large-scale moisture flux into Sahel and Indochina. 38 refs., 12 figs.

  1. Mutual interaction between the West African Monsoon on the summer Mediterranean climate

    NASA Astrophysics Data System (ADS)

    Gaetani, M.; Baldi, M.; Dalu, G. A.

    2009-04-01

    Many studies have show that the West African Monsoon (WAM) is teleconnected with neighbouring regions, as the Mediterranean (Med) basin and the Tropical Atlantic, but also it is sensitive to the perturbations occurring even in remote regions, as the Indian sub-continent and the Tropical Pacific, these teleconnections being active on several time-scales, from intraseasonal to multidecadal. The WAM plays also an active role in the regional atmospheric circulation, inducing significant changes in rainfall, moisture, temperature, and wind distribution up to the North Africa. Within this framework, recent works were focused on the teleconnection between WAM and Med. WAM is strengthened by the north-easterly advection of moisture from the Med Sea, and, since the subsiding monsoonal air often invades the Med, there is a 2-way interaction between WAM and Med summer circulation. We study these interactions, applying SVD analysis to global NCEP Reanalysis and to rainfall data from CMAP, during the extended monsoonal season from May to October, on interannual and on intraseasonal time-scale. Dynamical features are explored using composite analysis, focusing on the role of this connection in the heat waves occurrence in the Med. We find that a strong WAM intensifies the Hadley meridional circulation, with a strengthening of the north Atlantic anticyclone and a weakening, even blocking, of the westerly flow in the Med. A deep inland penetration of WAM produces a northern shift of the Libyan anticyclone, with subsidence and high pressure affecting mainly the western Med. The positive feedback is due to the intensification of north-easterly flow from the eastern Med, which, reaching the Sahara desert, intensifies the intertropical front, favouring abundant monsoonal precipitation because of the added moist air.

  2. Investigating Effects of Monsoon Winds on Hydrodynamics in the South China Sea

    NASA Astrophysics Data System (ADS)

    Chua, V. P.

    2013-12-01

    The South China Sea is a large marginal sea surrounded by land masses and island chains, and characterized by complex bathymetry and irregular coastlines. The circulation in South China Sea is subjected to seasonal and inter-annual variations of tidal and meteorological conditions. The effects of monsoon winds on hydrodynamics is investigated by applying spectral and harmonic analysis on surface elevation and wind data at stations located in the South China Sea. The analysis indicates varying responses to the seasonal monsoon depending on the location of the station. At Kaohsiung (located in northern South China Sea off Taiwan coast), tides from the Pacific Ocean and the southwest monsoon winds are found to be dominant mechanisms. The Kota Kinabalu and Bintulu stations, located to the east of South China Sea off Borneo coast, are influenced by low energy complex winds, and the shallow bottom bathymetry at these locations leads to tidal energy damping compared to other stations. The tidal dynamics at Tioman, located in southern South China Sea off Malaysia coast, are most responsive to the effects of the northeast monsoon. The complexity of our problem together with the limited amount of available data in the region presents a challenging research topic. An unstructured-grid SUNTANS model is employed to perform three-dimensional simulations of the circulation in South China Sea. Skill assessment of the model is performed by comparing model predictions of the surface elevations and currents with observations. The results suggest that the quality of the model prediction is highly dependent on horizontal grid resolution and coastline accuracy. The model may be used in future applications to investigate seasonal and inter-annual variations in hydrodynamics.

  3. 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.

  4. 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 (...

  5. 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.

  6. 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

  7. Multidisciplinary design optimization of optomechanical devices

    NASA Astrophysics Data System (ADS)

    Williams, Antonio St. Clair Lloyd

    2000-11-01

    The current process for designing optomechanical devices typically involves independent design optimization within each discipline. For instance, an optics engineer would optimize the optics of the device for image quality using ray-tracing software. The structural engineer would optimize the design to minimize deformation using the finite element method. Independently optimizing the optics and structures of optomechanical systems negates the possibility of exploiting the interdisciplinary interactions. This can lead to increased product development time and cost. Multidisciplinary Design Optimization (MDO) techniques have been in development over the last decade and have been applied primarily to aerospace problems. The goal of MDO is to take advantage of the interactions between disciplines as well as to improve the product development time. The application of MDO formulations to the design of Optomechanical systems has not been achieved thus far. The aim of this study is to evaluate and develop MDO formulations for optomechanical devices that may be used to reduce the product development time and cost. In addition, the feasibility of obtaining a more global optimum design using these multidisciplinary optimization techniques is investigated. Several MDO formulations were evaluated during this study and compared to the current design optimization process. The formulations evaluated were the Multidisciplinary Design Feasible (MDF), the Sequenced Individual Discipline Feasible (SDO-IDF), and the Sequenced Multidisciplinary Design Feasible (SDO-MDF). The current optimization process is called Independent Design Optimization (IDO). For the examples examined, the results showed that the IDO formulation optimizes each discipline but does not guarantee a multidisciplinary optimum for coupled problems. The SDO-MDF formulation was found to be the least efficient of the formulations examined, while the SDO-IDF showed the most promise in terms of efficiency.

  8. Bipolar modulation of millennial-scale West African monsoon variability during the last glacial (75,000-25,000 years ago)

    NASA Astrophysics Data System (ADS)

    Weldeab, Syee

    2012-04-01

    Time series of planktonic foraminiferal δ18O and Ba/Ca-based sea surface salinity (SSS) estimates from the eastern Gulf of Guinea (eastern equatorial Atlantic) indicate changes in runoff that reflect variability of spatially integrated precipitation over the equatorial West African monsoon area. Millennial-scale and recurring runoff-induced SSS rises and declines in the range of 1.5 and 2 psu (practical salinity unit) reveal rapid oscillation between dry and wet phases. The timing of decreased runoff coincides with oscillation of Dansgaard-Oeschger stadials and Heinrich events, the most severe monsoon weakening correlating with the latter. δ18Oresidual time series, derived by removing temperature, ice volume, and salinity components from the foraminiferal δ18O record, suggest that weak monsoon precipitation during stadials and Heinrich events was accompanied by significant shifts in δ18Oprecipitation toward higher values. Furthermore, δ18O analysis of individual tests of Globigerinoides ruber pink (δ18Oindiv) during dry episodes show a total range and variance of 2.3‰ and 0.25 (n = 121), indicating that seasonal contrast of sea surface freshening was significantly reduced during Heinrich events relative to that of interstadials which show a total range and variance of 3.35‰ and 0.42 (n = 140). On the basis of the timing and magnitude of changes in the monsoon record, it is evident that northern high latitude climate was the most dominant control on the West African monsoon variability. However, a southern high latitude imprint is also apparent during some episodes. This centennially resolved climate record demonstrates that the equatorial West African monsoon experienced profound changes in the amount, seasonal contrast, and moisture source of summer monsoon precipitation during the last glacial. The most plausible mechanism is a large-scale southward displacement of the monsoon trough, most likely initiated by large-scale reorganization of atmospheric

  9. 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.

  10. South Asian Summer Monsoon in CMIP5 GCMs

    NASA Astrophysics Data System (ADS)

    Ashfaq, M.; Rastogi, D.; Touma, D. E.

    2012-12-01

    Many Global Climate Models (GCMs) in the IPCC Fourth Assessment Report (AR4) suffered from substantial biases in their simulation of processes that govern summer monsoon dynamics in South Asia, leading to uncertainties in the simulation of monsoon response to future increases in greenhouse forcing. In order to test the ability of the current generation of GCMs that are part of the Coupled Model Inter-comparison Project Phase 5 (CMIP5) in the simulation of South Asian summer monsoon dynamics, we analyze the outputs from their historic simulations that correspond to 1970-1999 period. The analyses include the comparison of multiple monsoon indices including those representing monsoon onset, local circulations and global teleconnections, at seasonal, intra-seasonal and inter-annual time scales. We find that most of the GCMs are unable to simulate the timing of the summer monsoon onset over land, leading to substantial biases in seasonal precipitation means and variability, and intra-seasonal precipitation distribution. These errors are partly due to the fact that the majority of the GCMs exhibit a shift in the annual monsoon cycle with most of them exhibiting a precipitation peak in August in contrast to the observed peak in July, and that most of the GCMs substantially underestimate the strength of meridional troposhepric temperature gradient and vertical easterly shear during the summer season. We also find many models with low skill in the simulation of intra-seasonal temperature variability, and monsoon connection with local Hadley circulation and ENSO variability. These results have important implications for the reliability of future climate projections and impact assessments over South Asia.

  11. Transient coupling relationships of the Holocene Australian monsoon

    NASA Astrophysics Data System (ADS)

    McRobie, F. H.; Stemler, T.; Wyrwoll, K.-H.

    2015-08-01

    The northwest Australian summer monsoon owes a notable degree of its interannual variability to interactions with other regional monsoon systems. Therefore, changes in the nature of these relationships may contribute to variability in monsoon strength over longer time scales. Previous attempts to evaluate how proxy records from the Indonesian-Australian monsoon region correspond to other records from the Indian and East Asian monsoon regions, as well as to El Niño-related proxy records, have been qualitative, relying on 'curve-fitting' methods. Here, we seek a quantitative approach for identifying coupling relationships between paleoclimate proxy records, employing statistical techniques to compute the interdependence of two paleoclimate time series. We verify the use of complex networks to identify coupling relationships between modern climate indices. This method is then extended to a set of paleoclimate proxy records from the Asian, Australasian and South American regions spanning the past 9000 years. The resulting networks demonstrate the existence of coupling relationships between regional monsoon systems on millennial time scales, but also highlight the transient nature of teleconnections during this period. In the context of the northwest Australian summer monsoon, we recognise a shift in coupling relationships from strong interhemispheric links with East Asian and ITCZ-related proxy records in the mid-Holocene to significantly weaker coupling in the later Holocene. Although the identified links cannot explain the underlying physical processes leading to coupling between regional monsoon systems, this method provides a step towards understanding the role that changes in teleconnections play in millennial-to orbital-scale climate variability.

  12. Recent change of the global monsoon precipitation (1979-2008)

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Liu, Jian; Kim, Hyung-Jin; Webster, Peter J.; Yim, So-Young

    2012-09-01

    The global monsoon (GM) is a defining feature of the annual variation of Earth's climate system. Quantifying and understanding the present-day monsoon precipitation change are crucial for prediction of its future and reflection of its past. Here we show that regional monsoons are coordinated not only by external solar forcing but also by internal feedback processes such as El Niño-Southern Oscillation (ENSO). From one monsoon year (May to the next April) to the next, most continental monsoon regions, separated by vast areas of arid trade winds and deserts, vary in a cohesive manner driven by ENSO. The ENSO has tighter regulation on the northern hemisphere summer monsoon (NHSM) than on the southern hemisphere summer monsoon (SHSM). More notably, the GM precipitation (GMP) has intensified over the past three decades mainly due to the significant upward trend in NHSM. The intensification of the GMP originates primarily from an enhanced east-west thermal contrast in the Pacific Ocean, which is coupled with a rising pressure in the subtropical eastern Pacific and decreasing pressure over the Indo-Pacific warm pool. While this mechanism tends to amplify both the NHSM and SHSM, the stronger (weaker) warming trend in the NH (SH) creates a hemispheric thermal contrast, which favors intensification of the NHSM but weakens the SHSM. The enhanced Pacific zonal thermal contrast is largely a result of natural variability, whilst the enhanced hemispherical thermal contrast is likely due to anthropogenic forcing. We found that the enhanced global summer monsoon not only amplifies the annual cycle of tropical climate but also promotes directly a "wet-gets-wetter" trend pattern and indirectly a "dry-gets-drier" trend pattern through coupling with deserts and trade winds. The mechanisms recognized in this study suggest a way forward for understanding past and future changes of the GM in terms of its driven mechanisms.

  13. 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

  14. 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.

  15. Interannual and Interdecadal Variability of Thailand Summer Monsoon Season.

    NASA Astrophysics Data System (ADS)

    Singhrattna, Nkrintra; Rajagopalan, Balaji; Krishna Kumar, K.; Clark, Martyn

    2005-06-01

    Summer monsoon rains are a critical factor in Thailand's water resources and agricultural planning and management. In fact, they have a significant impact on the country's economic health. Consequently, understanding the variability of the summer monsoon rains over Thailand is important for instituting effective mitigating strategies against extreme rainfall fluctuations. To this end, the authors systematically investigated the relationships between summer monsoon precipitation from the central and northern regions of Thailand and large-scale climate features. It was found that Pacific sea surface temperatures (SSTs), in particular, El Niño-Southern Oscillation (ENSO), have a negative relationship with the summer monsoon rainfall over Thailand in recent decades. However, the relationship between summer rainfall and ENSO was weak prior to 1980. It is hypothesized that the ENSO teleconnection depends on the SST configuration in the tropical Pacific Ocean, that is, an eastern Pacific-based El Niño pattern, such as is the case in most of the post-1980 El Niño events, tends to place the descending limb of the Walker circulation over the Thailand-Indonesian region, thereby significantly reducing convection and consequently, rainfall over Thailand. It is believed that this recent shift in the Walker circulation is instrumental for the nonstationarity in ENSO-monsoon relationships in Thailand. El Niños of 1997 and 2002 corroborate this hypothesis. This has implications for monsoon rainfall forecasting and, consequently, for resources planning and management.

  16. What is the timing of orbital-scale monsoon changes?

    NASA Astrophysics Data System (ADS)

    Ruddiman, William F.

    2006-04-01

    A major (but little noted) divergence of opinion has developed among climate scientists over the orbital-scale periodicity and phasing of tropical monsoon variations. Kutzbach (1981. Monsoon climate of the early Holocene: climate experiment with Earth's orbital parameters for 9000 years ago. Science 214, 59-61) proposed that monsoons are driven by northern summer insolation at the precession period, but Clemens and Prell (1990. Late Pleistocene variability of Arabian Sea summer monsoon winds and continental aridity: eolian records from the lithogenic component of deep-sea sediments. Paleoceanography 5, 109-145; 2003. A 350,000-year summer-monsoon multi-proxy stack from the Owen Ridge, Northern Arabian Sea. Marine Geology 201, 35-51) inferred a more complicated response tied to latent heat transfer from the Southern Hemisphere. Because tropical monsoons affect climate over a vast area, resolving this divergence is an important task for the climate community. The purpose of this note is to highlight definitive evidence from high-resolution dating of speleothem calcite that provides unambiguous support for the Kutzbach hypothesis.

  17. 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

  18. 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...

  19. 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.

  20. The decadal-scale variation of the South Asian summer monsoon onset and its connection with the PDO

    NASA Astrophysics Data System (ADS)

    Watanabe, T.; Yamazaki, K.

    2013-12-01

    The summer Asian monsoon shows the abrupt increase of precipitation on the onset phase. It is an interesting and important problem when the summer monsoon onset occurs because natural resources, such as water and renewable energy agricultural product, are influenced by the variation of the summer Asian monsoon. Some researchers suggested the advance of the Asian summer monsoon onset in recent decades. We investigated the variation of the Asian monsoon onset using the long-term onset data over Kerala, a state in the southwest region of India, for 1948-2011. We discuss three main questions: 1) how is the variation of the monsoon onset date in the long-term period, 2) how the variation of the onset date is related to variations of atmospheric circulation and SST, and 3) what is the mechanism of such variation. Our main method is composite analysis using monthly-mean data. Though the onset date over Kerala shows the trend toward the early onset in recent three decades, such a trend is not observed in the whole period. It is noteworthy that the onset over Kerala shows the interannual variation on a multi-decadal scale. As regards the early onset years of Kerala, the summer monsoon onset is early over the following regions: the region from the southern Arabian Sea to southwestern India, the region from the southern Bay of Bengal to the Indochina Peninsula and the western North Pacific Ocean. On the other hand, the onset is late over southern China, Taiwan and the northern Philippine Sea. In early onset years of Kerala, the sea surface temperature over the northern Pacific Ocean is very similar to the negative PDO. The stationary wave train related with the negative PDO reaches into the Central Asia region, generates warm anomaly there and hence intensifies the land-sea thermal contrast there, which promotes the summer monsoon onset over South and Southeast Asia. Though the correlation between the onset over Kerala and the PDO is weak before 1976, it becomes high after

  1. 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.

  2. Inter-annual Variability of Monsoon Low Pressure Systems in Reanalysis and Climate model Simulation

    NASA Astrophysics Data System (ADS)

    Praveen, V.; Sandeep, S.; Ravindran, A. M.

    2014-12-01

    Monsoon Low Pressure Systems (LPS) play an important role in the Indian summer monsoon by bringing rainfall to the interior parts of Indian subcontinent. The detection and tracking of this weakly structured north north-west propagating system in reanalysis products and climate model simulations are challenging compared to the tropical and extra tropical cyclones. A robust method to objectively identify and track the LPS, which mimics the conventional LPS tracking technique, is presented. The algorithm showed its robustness in detecting and tracking LPS in ERA and MERRA reanalysis products. The algorithm fairly well captured inter-annual variability in ERA/MERRA LPSs against observations from Indian Meteorological Department (IMD). An analysis of the LPS in historical CMPI5 model simulation reveal, the models' skill in simulating a realistic mean monsoon precipitation and its relation to the LPS activity. Further, this inter-model variability in the LPS is found to be linked to the mid-tropospheric stability over the Bay of Bengal region.

  3. Experimental Seasonal Forecast of Monsoon 2005 Using T170L42 AGCM on PARAM Padma

    NASA Astrophysics Data System (ADS)

    Ratnam, J. Venkata; Sikka, D. R.; Kaginalkar, Akshara; Kesarkar, Amit; Jyothi, N.; Banerjee, Sudipta

    2007-09-01

    As a part of the Experimental Extended Range Monsoon Prediction Experiment, ensemble mode seasonal runs for the monsoon season of 2005 were made using the National Centre for Environmental Prediction (NCEP), T170L42 AGCM. The seasonal runs were made using six initial atmospheric conditions based on the NCEP operational analysis and with forecast monthly sea-surface temperature (SST) of the NCEP Coupled forecast system (CFS). These simulations were carried out on the PARAM Padma supercomputer of Centre for Development of Advanced Computing (C-DAC), India. The model climatology was prepared by integrating the model for ten years using climatological SST as the lower boundary. The climatology of the model compares well with the observed, in terms of the spatial distribution of rainfall over the Indian land mass. The model-simulated rainfall compares well with the Tropical Rainfall Measuring Mission (TRMM) estimates for the 2005 monsoon season. Compared to the model climatology (7.81 mm/day), the model had simulated a normal rainfall (7.75 mm/day) for the year 2005 which is in agreement with the observations (99% of long-term mean). However, the model could not capture the observed increase in September rainfall from that of a low value in August 2005. The circulation patterns simulated by the model are also comparable to the observed patterns. The ensemble mean onset is found to be nearer to the observed onset date within one pentad.

  4. 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.

  5. 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.

  6. The role of ocean salinity in the water cycle associated with Indian monsoon

    NASA Astrophysics Data System (ADS)

    Tang, W.; Yueh, S. H.; Liu, W. T.

    2014-12-01

    Indian monsoon is one of the most important of all tropical climate systems. Its onset and spatial/temporal variability have strong economic impact and may cause severe human suffering. Using sea surface salinity (SSS) data from Aquarius/SAC-D satellite mission, we study the seasonal and interannual variability of SSS, to identify the potential sources for the monsoon moisture supply. Preliminary analysis shows the rainfall integrated over India subcontinent, which often used as an indicator for the monsoon onset and intensity, is correlated higher with Aquarius SSS in Indian Ocean than the state-of-art estimate of evaporation (OAflux) minus precipitation (GPCP), indicating the important role of the oceanic processes. We also examine the relative importance of salinity tendency (dSSS/dt) and salinity advection at various stages of the monsoon. Ocean current data from OSCAR project is used to estimate the salinity advection. The role of ocean processes relative to other components of the water cycle is investigated in conjunction with data from multiple satellite missions. The atmospheric integrated moisture transport (IMT) is derived from ocean vector wind (OceanSAT2) and atmospheric precipitable water (SSMIS F17). Moisture in and out of the continent can be estimated by integrating IMT along the coasts, providing a quantitative description of moisture supply in the water budget. We analyze how IMT is influenced by oceanic processes and further related with large-scale circulation. This study underscores the importance of continuous good-quality and high-resolution spacebased observations towards the characterization, understanding, and prediction of the global water cycle.

  7. 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.

  8. 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.

  9. Variability of West African monsoon patterns generated by a WRF multi-physics ensemble

    NASA Astrophysics Data System (ADS)

    Klein, Cornelia; Heinzeller, Dominikus; Bliefernicht, Jan; Kunstmann, Harald

    2015-11-01

    The credibility of regional climate simulations over West Africa stands and falls with the ability to reproduce the West African monsoon (WAM) whose precipitation plays a pivotal role for people's livelihood. In this study, we simulate the WAM for the wet year 1999 with a 27-member multi-physics ensemble of the Weather Research and Forecasting (WRF) model. We investigate the inter-member differences in a process-based manner in order to extract generalizable information on the behavior of the tested cumulus (CU), microphysics (MP), and planetary boundary layer (PBL) schemes. Precipitation, temperature and atmospheric dynamics are analyzed in comparison to the Tropical Rainfall Measuring Mission (TRMM) rainfall estimates, the Global Precipitation Climatology Centre (GPCC) gridded gauge-analysis, the Global Historical Climatology Network (GHCN) gridded temperature product and the forcing data (ERA-Interim) to explore interdependencies of processes leading to a certain WAM regime. We find that MP and PBL schemes contribute most to the ensemble spread (147 mm month-1) for monsoon precipitation over the study region. Furthermore, PBL schemes have a strong influence on the movement of the WAM rainband because of their impact on the cloud fraction, that ranges from 8 to 20 % at 600 hPa during August. More low- and mid-level clouds result in less incoming radiation and a weaker monsoon. Ultimately, we identify the differing intensities of the moist Hadley-type meridional circulation that connects the monsoon winds to the Tropical Easterly Jet as the main source for inter-member differences. The ensemble spread of Sahel precipitation and associated dynamics for August 1999 is comparable to the observed inter-annual spread (1979-2010) between dry and wet years, emphasizing the strong potential impact of regional processes and the need for a careful selection of model parameterizations.

  10. A Pleistocene Indian Monsoon record from Heqing Basin, SW China

    NASA Astrophysics Data System (ADS)

    Qiang, X.; An, Z.; Shen, J.; Jin, Z.; Sun, Y.; Tong, G.; Chang, H.; Liu, X.; Liu, W.; Wang, S.; Zhou, W.; Song, Y.; Xiao, X.; Xiao, H.

    2008-12-01

    Heqing Basin (100°06'-100°16'E, 26°28'-26°46'N) is situated in southeastern margin of Tibetan Plateau, a geological conjunction zone of three tectonic units separated by Jinshajiang, Honghe and Xiaojinhe-Lijiang fault belts. Modern climate in this region is mainly influenced by Indian monsoon circulation. In Year 2002, a 665.83 m long core was retrieved from the Heqing basin under the support of Chinese Environmental Scientific Drilling program, which permits a high-resolution reconstruction of the Indian monsoon evolution from a continental perspective. The core mainly consists of gray clay, silty clay and silt. Magnetostratographic result generated by both thermal and alternating-field demagnetization methods indicates that the bottom age of the Heqing core is about 2.78 Myr. Multiple proxies (magnetic susceptibility, grain size, CaCO3 content, loss of ignite, pollen concentrations, and major/trace elements) were generated to reconstruct regional climate change and its dynamical links to Indian summer monsoon and solar insolation forcing. The results suggest that during glacial periods, this region is characterized by reduced vegetation cover (e.g., low total pollen concentration) and enhanced physical weathering (e.g., high Rb/Sr ratio), whereas during interglacial times, vegetation cover was extensive and chemical weathering is relatively strong around Heqing basin. Good correlation between variations in proxy indicators from Heqing core and stacked Indian summer monsoon record from Arabian Sea (Clemens and Prell, 2003) indicates that over the last 0.35 Myr, Heqing basin is predominantly influenced by Indian summer monsoon. Unlike Indian monsoon records from the Arabian Sea and Indian Ocean which resolution is relatively low, our high-resolution proxy variations permit a robust understanding of the Indian summer monsoon variations over the last 2.6 Myr. Comparisons of monsoon proxies from land and ocean indicate that solar insolation is the dominant factor

  11. The Impact of Local Meridional Circulations and Madden-Julian Oscillation on the Asian Summer Monsoon Precipitation in Pakistan

    NASA Astrophysics Data System (ADS)

    Minamide, M.; Koike, T.

    2013-12-01

    Since Pakistan locates in the west edge of Asian Summer Monsoon Region, the amount of precipitation there is severely influenced by the variability of monsoon activity. In some dry years such as in 1991 or 2002, Pakistan suffered from strong drought, causing great economic and life losses, while, in wet years such as 1994 or 2003, flood came to Pakistan, washing away whole cities. In order to reduce the damage of these water hazards, seasonal prediction is greatly effective, but due to the complicated mechanism of monsoon, it is still very challenging problem. In this research, we suppose ocean as one of the sources for seasonal precipitation trend, concentrating on the impact of atmospheric circulations on monsoonal precipitation, which is essential for the improvement of seasonal prediction. This research utilizes JRA25 reanalysis dataset and NOAA's OLR datasets. Correlation analysis between sea surface temperature and OLR over Pakistan on July showed that there is significant relationship between Arabian Sea and monsoonal precipitation in Pakistan. From the empirical Orthogonal Functions analysis conducted on zonally averaged mass stream function over Arabian Sea, the anomaly of atmospheric circulations over Arabian Sea is mainly composed of the anomaly of subtropical jets in Northern and Southern Hemisphere (Northern Hemisphere; Figure), and of the jet in lower troposphere around equator. Especially, the strength of Northern subtropical jet with Hadley-like circulation, which is derived from principle component, is strongly correlated with precipitation activity in Pakistan. On July of extremely dry (wet) years, downdraft in mid-latitude region associated with subtropical jet and Hadley-like circulation are strengthened (weakened), so that monsoonal precipitation is suppressed (enhanced). The strength of those circulations greatly changes intra-seasonally, and, as Sajani et al. (2007) indicates, Madden-Julian Oscillation is a good source of these intra

  12. 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

  13. 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

  14. Asian Black Carbon Influence on East Asian Summer Monsoons

    NASA Astrophysics Data System (ADS)

    Mahmood, R.; Li, S.

    2011-12-01

    Since the black carbon (BC) emission in East and South Asia has increased significantly during the last decades of the 20th century, there is an ever growing concern about its impact on Asian monsoon. In this study we provide an in-depth analysis of the influence by performing several ensemble sensitive experiments with or without historical BC concentrations over East Asia, South Asia, and the combined East and South Asia in an atmospheric general circulation model, GFDL AM2.1. The results show that: (a) The East Asian summer climate is sensitive to the East Asian BC (EABC) concentrations in a sense that EABC contributes significantly to the frequently occurring north-drought and south-flood patterns in Eastern China. In detail, the large scale precipitation anomalies induced by EABC characterize more rainfalls over central/south China, East China Sea and southern Japan and less rainfall over northern China and the west Pacific region between 10N to 20N. These anomalous precipitation patterns are mainly attributed to the EABC induced large scale circulation changes including the weakened Western Pacific Subtropical High (WPSH), anomalous ascent motions over central-southern China (centering over the Yangtze River valley (YRV)) and the subsequent descent motions over northern China and the South China Sea. These modeled results suggest that the EABC experiment reproduces the climate shift event of eastern China during the late 1970s, including intensified rainfall in the YRV and the weakened summer monsoonal circulation. (b) The anomalous results of South Asian BC (SABC) experiment signify a tri-polar precipitation response over East Asia, with a reduction from the YRV to East China Sea and southern Japan sandwiched with increases over a northern domain from northern China/ Korea to northern Japan and over southern China. As for southern China, particularly the YRV, the impact of SABC is to offset a fraction of intensified rainfall induced by local BC of East Asia

  15. 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

  16. Virtual multidisciplinary teams for cancer care.

    PubMed

    Axford, A T; Askill, C; Jones, A J

    2002-01-01

    A recent report on cancer services in Wales recommended an integrated cancer service. The proposed model was difficult to introduce in rural areas, where health-care sites and staff are far apart. Videoconferencing equipment was installed in the Singleton Hospital, Swansea, and the Bronglais General Hospital, Aberystwyth, 120 km away. During the first year, 42 videoconferencing multidisciplinary team meetings were held using ISDN at 384 kbit/s. A total of 202 cases were reviewed. The cancers were colorectal, breast and lung. There was only one aborted session, which was due to an ISDN line fault. The average attendance at the meetings was 15 staff, of whom eight were essential team members. Regular multidisciplinary team meetings reduced the need for patients to travel. They also increased access to expert opinion and reduced the delay in implementing treatment.

  17. [Integrated multidisciplinary treatment modalities for obesity].

    PubMed

    Yu, Jian-chun

    2010-02-01

    The rapid increase of obesity nationwide and worldwide has threatened human health and caused the increase of metabolic diseases and the changes of disease spectrum. Its co-morbidities, mortality, and relevant socio-economic issues have became global concerns. Integrated multidisciplinary treatment modalities have emerged in recent years. For severely obese patients body mass index (BMI>40 kg/m(2) or obese patients (BMI 35 - 40 kg/m(2)) with co-morbidities such as severe diabetes, obesity-associated cardiac lesions, severe sleep apnea, infertility, and osteoarthritis that affect the daily life, minimally invasive laparoscopic bariatric surgery (such as Lap Banding) can achieve satisfactory results by reducing body weight in long term, treating or preventing the co-morbidities, and ultimately decreasing mortality. Multidisciplinary treatment modalities for tumors, obesity, and other diseases have been widely adopted. This strategy may play increasingly important roles in improving the treatment effectiveness, upgrading healthcare services, and addressing interdisciplinary problems. PMID:20236577

  18. [Multidisciplinary oncology teams: beware of endless discussions].

    PubMed

    Giard, Raimond W M

    2010-01-01

    The continual and increasing complexity of diagnostic and treatment options in oncology demands careful communication, coordination and decision making. Cancer care could be improved by multidisciplinary teamwork. Although this sort of teamwork has many advantages in theory, we know very little about its effectiveness in practice. We have to answer questions such as how teams can accomplish their task most effectively and how we must manage organizations in such a way that team-based working contributes optimally to organizational effectiveness.

  19. [Multidisciplinary treatment of locally advanced rectal cancer].

    PubMed

    Faes, Seraina; Gié, Olivier; Demartines, Nicolas; Hahnloser, Dieter

    2016-06-15

    Treatment of patients with locally advanced rectal cancer remains challenging. Preoperative imaging with pelvic MRI allows to identify patients for multimodal treatment including induction chemothe- rapy or neoadjuvant radio-chemotherapy and an extended surgical resection. With multidisciplinary approach and an experienced team, excellent oncologic results may be achieved, as well as a good function and quality of life, even with preservation of the anus in the majority of patients. PMID:27487624

  20. [Bariatric surgery and multidisciplinary treatment for obesity].

    PubMed

    Yu, Jian-chun

    2011-06-01

    Bariatric surgery is one of the most effective treatment options for obesity. Compared with laparoscopic adjustable gastric banding (LAGB), laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery has demonstrated more benefits and surgical risks. Bariatric surgery can result in the decreases in multiple gastrointestinal hormone levels, which can partially explain the mechanisms behind weight loss and resolution of diabetes after bariatric surgery. The management after bariatric surgery should be multidisciplinary and comprehensive, including dietary adjustment, physical exercise, behavioral intervention, and drug therapy.

  1. Subtropical circulation, Tibetan Plateau, and Asian Summer Monsoon

    NASA Astrophysics Data System (ADS)

    Wu, G. X.

    2015-12-01

    The characteristics of the land-air-sea interaction in summer subtropics and their impacts on climate were revealed. It was shown that different kind of diabatic heating plays different roles in the formation of the subtropical circulation where the surface sensible heating associated with the land-sea distribution plays a fundamentally important role, and the three spatial- scales of atmospheric forcing contribute in various ways to the formation of aridity/desert over the western parts of continents and wet/monsoon over the eastern parts. Thus monsoon and desert coexist as twin features. It was identified that the onset of the Asian summer monsoon (ASM) consists of three dynamically consequential stages: the onset first occurs over the eastern Bay of Bengal (BOB) in early May, which is followed by the onset over the South China Sea in mid-May, and the Indian Monsoon onset in early June. During such an onset progression, the formation, maintenance and evolution of the South Asian High (SAH) play a significant role in generating the upper tropospheric dumping. In the lower troposphere, the development of the BOB monsoon onset vortex, the ASM onset barrier, the cross equatorial SST gradient and the forced convection over the eastern Arabian Sea also regulate the onset evolution. In winter the Tibetan Plateau (TP) can inspire a stationary dipole-type atmospheric wave, forming a specific climate pattern in Asia. In spring, such a dipole circulation forms the unique persistent rainfall over Southern China. The TP forcing can also anchor the ASM onset over the BOB by generating the unique short- life BOB SST warm pool and modulating the SAH in the upper troposphere. In summer the thermal forcing of the Tibetan-Iranian Plateau plays a significant role in controlling the Asian monsoon by transporting water vapor from the sea to the land for the genesis of continental monsoon. The TP thermal forcing also modulates the regional climate variability in different time scales.

  2. Multidisciplinary approach to implants: a review.

    PubMed

    Ng, Doreen Y; Wong, Andrew Y C; Liston, Peter N

    2012-12-01

    As implant dentistry grows in popularity, greater numbers of general dental practitioners (GDPs) are offering this service to their patients. In order to improve treatment success for both patient and practitioner, a multidisciplinary approach to implant planning and placement should be taken. However, the literature currently holds few articles which offer advice to the GDP on how to take a multidisciplinary approach to implant treatment. The aim of this review is to provide practitioners with evidence-based guidance for taking a multidisciplinary approach to implant treatment. A MEDLINE/PubMed search for articles published between 1980 and mid-2012 was undertaken. The search strategy used different combinations of the following terms: dental implants, osseointegration, medical contraindications, patient habits, radiography, prosthodontics, endodontics, orthodontics, periodontics and surgical factors. The review demonstrated the importance of thorough medical and dental history-taking, and how different facets of each speciality contribute to the outcome of implant treatment. Successful implant treatment is the result of careful planning and integration of various areas of dentistry, not just those of prosthodontics and surgery. PMID:23477010

  3. 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

  4. 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

  5. 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

  6. 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.

  7. 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

  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. Characteristics of clouds and precipitation in the Western Indian monsoon regime

    NASA Astrophysics Data System (ADS)

    Chakravarty, K.; Pandithurai, G.

    2013-12-01

    The rainfall and raindrop size distribution measured with JW-Disdrometer has been utilized to study the characteristic features of precipitation during the monsoon and post-monsoon months over two tropical stations of India, i.e., Pune (sea-surface height = 560 m; annual rainfall = 660 mm) and Mahabaleshwar (sea-surface height = 1438 m; annual average rainfall = 8000mm) along the Western Ghat mountain range. The stations show distinct pattern of raindrop size distribution and other integrated rainfall parameters during the two seasons. The factors affecting these variations have also been discussed in the present paper. A case study of two rain events over Pune on July 31, 2012 and October 26, 2012 of nearly same rain rate (~ 60 mm/hr) have been made to characterize the monsoon and post monsoon rainfall respectively. It is clearly seen from the analysis that the drops of larger diameter dominates the post monsoon month over Pune whereas smaller drops shows its prominent presence in the monsoon months for nearly same rain rate. This is because, the rain in the month of October is basically convective in nature, as result of which the presence of strong updraft carries the smaller drops that are having the fall velocities smaller than the drafts to the higher altitude, thereby allowing the bigger drops to precipitate locally Such conditions are very rarely seen in the monsoon rainfall i.e. during the month of July. In order to get into the more insight about the rainfall pattern, 4 different rain events have been chosen from the above two stations, i.e Pune and Mahabaleshwar and they are classified as convective and stratiform rainfall on the basis of certain parameters. The events which has been considered as stratiform rainfall have the rain rate in the range of 0.5-5 mm/hr and standard deviation of rain < 1.5 whereas the rain events which has been considered as convective rainfall has the rain rate > 5 mm/hr and standard deviation of rain > 1.5. By taking the

  10. 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

  11. Strong modulations on the Bay of Bengal monsoon onset vortex by the first northward-propagating intra-seasonal oscillation

    NASA Astrophysics Data System (ADS)

    Li, Kuiping; Li, Zhi; Yang, Yang; Xiang, Baoqiang; Liu, Yanliang; Yu, Weidong

    2016-07-01

    Monsoon onset vortex (OV) in the form of tropical cyclone is often observed in the pre-monsoon period and contributes to the subsequent abrupt establishment of summer monsoon over the Bay of Bengal (BoB). It is identified here that all historical OVs occurred during the convection-enhanced phase of the first northward-propagating intra-seasonal oscillation (FNISO). The individual contributions from the four large scale environmental fields associated with the intra-seasonal variations to the cyclone genesis are diagnosed with the aid of the genesis potential index. The significant moistening of mid-level atmosphere, which is embedded in the FNISO convection-enhanced phase, is shown to be the primary factor leading to the cyclone genesis. The water vapor budget analysis is further done to understand the governing process for the mid-level humidity increase. It is clearly seen that the vertical advection process, dominated by the anomalous vertical advection of the mean vertical water vapor gradient, plays the critical role. Hence the OVs are shown to be strongly modulated by FNISOs, both of which are important elements of the complex story of the BoB monsoon onset.

  12. 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.

  13. Entrainment and mixing mechanism in monsoon clouds

    NASA Astrophysics Data System (ADS)

    Bera, Sudarsan; Prabhakaran, Thara; Pandithurai, Govindan; Brenguier, Jean-Louis

    2015-04-01

    Entrainment and consequent mixing impacts the cloud microphysical parameters and droplet size distribution (DSD) significantly which are very important for cloud radiative properties and the mechanism for first rain drop formation. The entrainment and mixing mechanisms are investigated in this study using in situ observations in warm cumulus clouds over monsoon region. Entrainment is discussed in the framework of the homogeneous and inhomogeneous mixing concepts and their effects on cloud droplet size distribution, number concentration, liquid water content and mean radius are described. The degree of homogeneity increases with droplet number concentration and adiabatic fraction, indicating homogeneous type mixing in the cloud core where dilution is less. Inhomogeneous mixing is found to be a dominating process at cloud edges where dilution is significant. Cloud droplet size distribution (DSD) is found to shift towards lower sizes during a homogeneous mixing event in the cloud core whereas spectral width of DSD decreases due to inhomogeneous mixing at cloud edges. Droplet size spectra suggests that largest droplets are mainly formed in the less diluted cloud core while diluted cloud edges have relatively smaller droplets, so that raindrop formation occurs mainly in the core of the cloud. The origin of the entrained parcels in deep cumulus clouds is investigated using conservative thermodynamical parameters. The entrained parcels originate from a level close to the observation level or slightly below through lateral edges. Cloud edges are significantly diluted due to entrainment of sub-saturated environmental air which can penetrate several hundred meters inside the cloud before it gets mixed completely with the cloud mass. Less diluted parcels inside the cloud core originates from a level much below the cloud base height. Penetrating downdraft from cloud top is seldom observed at the observation level and strong downdrafts may be attributed to in-cloud oscillation

  14. Transformation of the multidisciplinary diabetic foot clinic into a multidisciplinary diabetic foot day unit: results from a service evaluation.

    PubMed

    Manu, Chris A; Mustafa, Omar G; Bates, Maureen; Vivian, Gill; Mulholland, Nicola; Elias, David; Huang, Dean Y; Deane, Colin; Cavale, Naveen; Kavarthapu, Venu; Rashid, Hisham; Edmonds, Michael

    2014-09-01

    The natural history of the diabetic foot is aggressive and complex. To counteract this, we describe the transformation of a Multidisciplinary Diabetic Foot Clinic into a Multidisciplinary Diabetic Foot Day Unit, which delivers an emergency open access system for patients, with a "one-stop," same day service in which investigations are performed, results reviewed and treatment implemented. It also provides joint clinics with vascular, orthopaedic, and plastic surgeons and specialized clinics for casting of complex neuropathic feet and for the administration of intravenous or intramuscular antibiotics on the same day. The aim was to document these increasingly wide-ranging facilities by undertaking a retrospective evaluation over a 6-week period, with analysis of notes, investigations, and an anonymous patient satisfaction survey. The clinic was visited by 597 patients who attended in 1076 appointments, of which 112 (10.4%) were emergency visits; these patients attended the clinic without a booked appointment but via an open access policy, 93 of whom were known to the clinic, but 19 were new self-referred patients to the service. Furthermore, 197 (18%) were seen in a Joint Vascular Diabetic Foot Clinic and 98 (9%) were seen in a Joint Orthopaedic Plastic Diabetic Foot Clinic, 570 (53%) were seen in an Active Ulcer Clinic and 97 (9%) in a Total Contact Casting Clinic. Forty-five percent of patients were prescribed antibiotics, including 188 (76%) as oral and 45(18%) as intravenous antibiotics and 15(6%) as intramuscular injections. Of the 1076 appointments, 150 (14%) patients were in the foot clinic for more than 4 hours. Sixty (10%) patients were reviewed 4 or more times over the 6-week period. Only 22 (2%) were admitted to hospital. Of the 125 survey responders, 98% were satisfied with this service, which has evolved from a Diabetic Foot Clinic into a Multidisciplinary Diabetic Foot Day Unit.

  15. Monsoons in a changing world: A regional perspective in a global context

    NASA Astrophysics Data System (ADS)

    Kitoh, Akio; Endo, Hirokazu; Krishna Kumar, K.; Cavalcanti, Iracema F. A.; Goswami, Prashant; Zhou, Tianjun

    2013-04-01

    provide a new view of global and regional monsoonal rainfall, and their changes in the 21st century under RCP4.5 and RCP8.5 scenarios as projected by 29 climate models that participated in the Coupled Model Intercomparison Project phase 5. The model results show that the global monsoon area defined by the annual range in precipitation is projected to expand mainly over the central to eastern tropical Pacific, the southern Indian Ocean, and eastern Asia. The global monsoon precipitation intensity and the global monsoon total precipitation are also projected to increase. Indices of heavy precipitation are projected to increase much more than those for mean precipitation. Over the Asian monsoon domain, projected changes in extreme precipitation indices are larger than over other monsoon domains, indicating the strong sensitivity of Asian monsoon to global warming. Over the American and African monsoon regions, projected future changes in mean precipitation are rather modest, but those in precipitation extremes are large. Models project that monsoon retreat dates will delay, while onset dates will either advance or show no change, resulting in lengthening of the monsoon season. However, models' limited ability to reproduce the present monsoon climate and the large scatter among the model projections limit the confidence in the results. The projected increase of the global monsoon precipitation can be attributed to an increase of moisture convergence due to increased surface evaporation and water vapor in the air column although offset to a certain extent by the weakening of the monsoon circulation.

  16. 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.

  17. 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.

  18. 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

    2015-01-01

    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.

  19. 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.

  20. 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.

  1. 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.

  2. 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. PMID:25219854

  3. 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

  4. 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

  5. Global monsoon precipitation responses to large volcanic eruptions

    NASA Astrophysics Data System (ADS)

    Liu, Fei; Chai, Jing; Wang, Bin; Liu, Jian; Zhang, Xiao; Wang, Zhiyuan

    2016-04-01

    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.

  6. Global monsoon precipitation responses to large volcanic eruptions.

    PubMed

    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

  7. Rethinking the Recent Advance of Asian Summer Monsoon Onset

    NASA Astrophysics Data System (ADS)

    Xiang, B.; Wang, B.

    2012-12-01

    Understanding the monsoon onset change is of utmost importance especially for agriculture planning and water management. In the last three decades, Asian Summer Monsoon (ASM) onset has remarkably advanced, but the physical mechanisms remain elusive. Since the overall ASM onset occurs in May, we focus on the change of mean fields in May and consider enhanced mean precipitation and monsoon westerly winds as signs of advanced onset. Results show that the advanced ASM onset mainly represents a robust decadal shift in the mid-to-late 1990s, which is attributed to the mean state change in the Pacific basin characterized by a grand La Niña-like pattern. The La Niña-like mean state change controls the ASM onset through the westward propagation of Rossby waves and its interaction with the asymmetric background mean states in the Indian Ocean and western Pacific, which facilitates the amplification of the northern hemispheric perturbations as well as intensified westerly winds. Intriguingly, the abrupt decadal shifts of monsoon onset in the Arabian Sea and Bay of Bengal occur in 1999, in contrast to the South China Sea with decadal shift in 1994. Numerical experiments demonstrate that the advanced monsoon onset in the Arabian Sea and Bay of Bengal is governed by the enhanced zonal sea surface temperature (SST) gradients in the equatorial Pacific, while that in the South China Sea is primarily determined by the abrupt SST warming near the Philippine Sea.

  8. 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

    2016-01-01

    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 (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. PMID:27071753

  9. 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

    2015-01-01

    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

  10. Extratropical anticyclonic Rossby wave breaking and Indian summer monsoon failure

    NASA Astrophysics Data System (ADS)

    Samanta, Dhrubajyoti; Dash, M. K.; Goswami, B. N.; Pandey, P. C.

    2016-03-01

    Interactions between midlatitude disturbances and the monsoonal circulation are significant for the Indian summer monsoon (ISM) rainfall. This paper presents examples of monsoon-midlatitude linkage through anticyclonic Rossby wave breaking (RWB) over West Asia during June, July and August of the years 1998-2010. RWB events over West Asia are identified by the inversion of the potential vorticity air mass at three different isentropic levels (340, 350, and 360 K) using daily NCEP-NCAR reanalysis. It is observed that RWB took place over West Asia before/during breaks in the ISM. Further, these events occur on the anticyclonic shear side of the subtropical jet, where the gradient of the zonal wind is found to be high. RWB is responsible for the southward movement of high potential vorticity air from the westerly jet, leading to the formation of a blocking high over the Arabian region. In turn, this blocking high advects and causes the descent of upper tropospheric cold and dry air towards Central India. Such an air mass with low moist static energy inhibits deep monsoonal convection and thereby leads to a dry spell. In fact, we find that RWB induced blocking over West Asia to be one of the major causes of dry spell/break episodes in ISM. Additionally, the presence of cold air over Central India reduces the north-south thermal contrast over the monsoon region thereby modifying the local Hadley circulation over the region.

  11. 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.

  12. 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.

  13. 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

  14. Variation in the Asian monsoon intensity and dry-wet conditions since the Little Ice Age in central China revealed by an aragonite stalagmite

    NASA Astrophysics Data System (ADS)

    Yin, J.-J.; Yuan, D.-X.; Li, H.-C.; Cheng, H.; Li, T.-Y.; Edwards, R. L.; Lin, Y.-S.; Qin, J.-M.; Tang, W.; Zhao, Z.-Y.; Mii, H.-S.

    2014-10-01

    This paper focuses on the climate variability in central China since AD 1300, involving: (1) a well-dated, 1.5-year resolution stalagmite δ18O record from Lianhua Cave, central China (2) links of the δ18O record with regional dry-wet conditions, monsoon intensity, and temperature over eastern China (3) correlations among drought events in the Lianhua record, solar irradiation, and ENSO (El Niño-Southern Oscillation) variation. We present a highly precise, 230Th / U-dated, 1.5-year resolution δ18O record of an aragonite stalagmite (LHD1) collected from Lianhua Cave in the Wuling Mountain area of central China. The comparison of the δ18O record with the local instrumental record and historical documents indicates that (1) the stalagmite δ18O record reveals variations in the summer monsoon intensity and dry-wet conditions in the Wuling Mountain area. (2) A stronger East Asian summer monsoon (EASM) enhances the tropical monsoon trough controlled by ITCZ (Intertropical Convergence Zone), which produces higher spring quarter rainfall and isotopically light monsoonal moisture in the central China. (3) The summer quarter/spring quarter rainfall ratio in central China can be a potential indicator of the EASM strength: a lower ratio corresponds to stronger EASM and higher spring rainfall. The ratio changed from <1 to >1 after 1950, reflecting that the summer quarter rainfall of the study area became dominant under stronger influence of the Northwestern Pacific High. Eastern China temperatures varied with the solar activity, showing higher temperatures under stronger solar irradiation, which produced stronger summer monsoons. During Maunder, Dalton and 1900 sunspot minima, more severe drought events occurred, indicating a weakening of the summer monsoon when solar activity decreased on decadal timescales. On an interannual timescale, dry conditions in the study area prevailed under El Niño conditions, which is also supported by the spectrum analysis. Hence, our record

  15. 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

  16. The West African Monsoon: variability and teleconnection with ENSO during the years 1948-57

    NASA Astrophysics Data System (ADS)

    Stickler, Alexander; Brönnimann, Stefan

    2010-05-01

    The intensity of the West African Monsoon (WAM) has been shown to be influenced by different factors. Most important for the existence of the monsoon system is the land-sea thermal contrast between the North African landmass and the Gulf of Guinea. ENSO plays an important role for its interannual variability via an atmospheric teleconnection bridging the Pacific and Atlantic oceanic basins and favouring either descent/weak low-level monsoon flow or ascent/strong low-level monsoon flow over tropical West Africa. Most published studies on the WAM variability are based on reanalysis datasets. However, while reproducing quite well the interannual variability, reanalysis products have been found to contain major biases in certain tropical regions before 1968. These lead to an unrealistic low frequency behaviour and might be explained by the lack of observations assimilated into the reanalyses, as is the case e.g. for tropical Africa where only the much sparser radiosonde data have been assimilated into the NCEP/NCAR Reanalysis (NNR). Here we present an analysis of the interannual WAM variability and its teleconnection with ENSO for the years 1948-57 which is not based on a reanalysis, but on early pilot balloon observational wind data from the Comprehensive Historical Upper Air Network (CHUAN). We have examined wind data from all 36 stations located in the domain (10°S-30°N, 20°W-20°E) on 5 levels up to the mid troposphere (corresponding roughly to the 925, 850, 700, 600 and 500 hPa pressure levels). This analysis shows that 7 subregions can be defined which are characterised by similar vertical wind profiles as well as seasonality: the NW (Mauritania, northern Senegal), the SW (southern Senegal to coastal Guinea), central sub-Saharan West Africa (SSWA, from interior Guinea in the W to coastal Cameroon and southern Niger in the E), central and eastern Niger, western Chad, the western Central African Republic, and the southern coastal regions east of the Gulf of

  17. [Psychic changes in systemic lupus erythematosus: a multidisciplinary prospective study].

    PubMed

    Miguel Filho, E C; Pereira, R M; Busatto Filho, G; Shavitt, R G; Hirsch, R; de Sá, L C; de Arruda, P C

    1990-01-01

    Despite the high prevalence of psychic symptoms in lupus patients, there are few systematic studies in this area. Through a multidisciplinary approach, the authors developed a prospective study to characterize and correlate psychopathological aspects with clinical and laboratory data concerning neural manifestations of the disease. Out of 23 patients studied, 12 showed psychic alterations, which were interpreted as primary manifestations of the disease. All of them presented organic mental syndromes (DSM-III-R) in which cognitive symptoms were the most prominent, followed by affective, catatonic and hallucinatory features. The neurologic findings (seizure, migraine and muscular atrophy), as well as the ophthalmologic alterations (hemorrhage and soft exudates) were frequent and concomitant with the psychic features. The laboratory findings were: LE cells 50%; anti-Sm: 16%; anti-U1 RNP: 50%; anti-Ro/SS-A: 50%; anti-nDNA: 58%; decreased CH50 or fractions (C3, C4): 67%; anti-P: 18%; antigangliosides IgG: 67%; antigangliosides IgM: 78%. The cerebrospinal fluid analysis showed: increased cellularity: 18%; elevated protein: 36%; antigangliosides IgG: 67%; antigangliosides IgM: 33%; immunocomplexes: 36%. In spite of the absence of an adequate control group and of the small number of patients, the multidisciplinary approach leads to a better characterization of the nervous system involvement in this disease. PMID:1965671

  18. New Approaches to HSCT Multidisciplinary Design and Optimization

    NASA Technical Reports Server (NTRS)

    Schrage, Daniel P.; Craig, James I.; Fulton, Robert E.; Mistree, Farrokh

    1999-01-01

    New approaches to MDO have been developed and demonstrated during this project on a particularly challenging aeronautics problem- HSCT Aeroelastic Wing Design. To tackle this problem required the integration of resources and collaboration from three Georgia Tech laboratories: ASDL, SDL, and PPRL, along with close coordination and participation from industry. Its success can also be contributed to the close interaction and involvement of fellows from the NASA Multidisciplinary Analysis and Optimization (MAO) program, which was going on in parallel, and provided additional resources to work the very complex, multidisciplinary problem, along with the methods being developed. The development of the Integrated Design Engineering Simulator (IDES) and its initial demonstration is a necessary first step in transitioning the methods and tools developed to larger industrial sized problems of interest. It also provides a framework for the implementation and demonstration of the methodology. Attachment: Appendix A - List of publications. Appendix B - Year 1 report. Appendix C - Year 2 report. Appendix D - Year 3 report. Appendix E - accompanying CDROM.

  19. Multidisciplinary Aerodynamic-Structural Shape Optimization Using Deformation (MASSOUD)

    NASA Technical Reports Server (NTRS)

    Samareh, Jamshid A.

    2000-01-01

    This paper presents a multidisciplinary shape parameterization approach. The approach consists of two basic concepts: (1) parameterizing the shape perturbations rather than the geometry itself and (2) performing the shape deformation by means of the soft object animation algorithms used in computer graphics. Because the formulation presented in this paper is independent of grid topology, we can treat computational fluid dynamics and finite element grids in the same manner. The proposed approach is simple, compact, and efficient. Also, the analytical sensitivity derivatives are easily computed for use in a gradient-based optimization. This algorithm is suitable for low-fidelity (e.g., linear aerodynamics and equivalent laminate plate structures) and high-fidelity (e.g., nonlinear computational fluid dynamics and detailed finite element modeling) analysis tools. This paper contains the implementation details of parameterizing for planform, twist, dihedral, thickness, camber, and free-form surface. Results are presented for a multidisciplinary application consisting of nonlinear computational fluid dynamics, detailed computational structural mechanics, and a simple performance module.

  20. Multidisciplinary Aerodynamic-Structural Shape Optimization Using Deformation (MASSOUD)

    NASA Technical Reports Server (NTRS)

    Samareh, Jamshid A.

    2000-01-01

    This paper presents a multidisciplinary shape parameterization approach. The approach consists of two basic concepts: (1) parameterizing the shape perturbations rather than the geometry itself and (2) performing the shape deformation by means of the soft object animation algorithms used in computer graphics. Because the formulation presented in this paper is independent of grid topology, we can treat computational fluid dynamics and finite element grids in a similar manner. The proposed approach is simple, compact, and efficient. Also, the analytical sensitivity derivatives are easily computed for use in a gradient-based optimization. This algorithm is suitable for low-fidelity (e.g., linear aerodynamics and equivalent laminated plate structures) and high-fidelity (e.g., nonlinear computational fluid dynamics and detailed finite element modeling analysis tools. This paper contains the implementation details of parameterizing for planform, twist, dihedral, thickness, camber, and free-form surface. Results are presented for a multidisciplinary design optimization application consisting of nonlinear computational fluid dynamics, detailed computational structural mechanics, and a simple performance module.

  1. A relational conceptual framework for multidisciplinary health research centre infrastructure

    PubMed Central

    2010-01-01

    Although multidisciplinary and team-based approaches are increasingly acknowledged as necessary to address some of the most pressing contemporary health challenges, many researchers struggle with a lack of infrastructure to facilitate and formalise the requisite collaborations. Specialised research centres have emerged as an important organisational solution, yet centre productivity and sustainability are frequently dictated by the availability and security of infrastructure funds. Despite being widely cited as a core component of research capacity building, infrastructure as a discrete concept has been rather analytically neglected, often treated as an implicit feature of research environments with little specification or relegated to a narrow category of physical or administrative inputs. The terms research infrastructure, capacity, and culture, among others, are deployed in overlapping and inconsistent ways, further obfuscating the crucial functions of infrastructure specifically and its relationships with associated concepts. The case is made for an expanded conceptualisation of research infrastructure, one that moves beyond conventional 'hardware' notions. Drawing on a case analysis of NEXUS, a multidisciplinary health research centre based at the University of British Columbia, Canada, a conceptual framework is proposed that integrates the tangible and intangible structures that interactively underlie research centre functioning. A relational approach holds potential to allow for more comprehensive accounting of the returns on infrastructure investment. For those developing new research centres or seeking to reinvigorate existing ones, this framework may be a useful guide for both centre design and evaluation. PMID:20925953

  2. New Approaches to HSCT Multidisciplinary Design and Optimization

    NASA Technical Reports Server (NTRS)

    Schrage, D. P.; Craig, J. I.; Fulton, R. E.; Mistree, F.

    1996-01-01

    The successful development of a capable and economically viable high speed civil transport (HSCT) is perhaps one of the most challenging tasks in aeronautics for the next two decades. At its heart it is fundamentally the design of a complex engineered system that has significant societal, environmental and political impacts. As such it presents a formidable challenge to all areas of aeronautics, and it is therefore a particularly appropriate subject for research in multidisciplinary design and optimization (MDO). In fact, it is starkly clear that without the availability of powerful and versatile multidisciplinary design, analysis and optimization methods, the design, construction and operation of im HSCT simply cannot be achieved. The present research project is focused on the development and evaluation of MDO methods that, while broader and more general in scope, are particularly appropriate to the HSCT design problem. The research aims to not only develop the basic methods but also to apply them to relevant examples from the NASA HSCT R&D effort. The research involves a three year effort aimed first at the HSCT MDO problem description, next the development of the problem, and finally a solution to a significant portion of the problem.

  3. [Results of the multidisciplinary treatment of invasive bladder cancer].

    PubMed

    Miyakawa, M; Oishi, K; Okada, Y; Takeuchi, H; Okada, K; Yoshida, O

    1986-12-01

    Of the 843 patients with bladder cancer treated at Kyoto University between 1965 and 1984, 156 patients (18.6%) received total cystectomy. Between 1980 and 1984, 60 patients underwent multidisciplinary treatment with 4,000 or 2,400 rad adjuvant preoperative radiation therapy to the whole pelvis followed by radical cystectomy with or without postoperative adjuvant chemotherapy. The 5-year survival rate for the 65 patients with pelvic lymphadenectomy was 66% and that for the 40 patients without lymphadenectomy or only biopsy was 35%. The 5-year survival rate after radical cystectomy for 20 bladder cancer patients with regional lymph node metastasis was 11% and 73% for 59 patients without lymph node metastasis (p less than 0.001). The survival rate of multidisciplinary treatment protocol for muscle invasive bladder cancer was 55% a significantly (p less than 0.05) improved survival compared to the historical control. For analysis, the patients were divided into 2 categories according to histological criteria for evaluation of therapeutic effects for preoperative radiation by Ohoshi and Shimosato. The two groups were non-responder: grade I and IIa changes and responder: grade IIb, III and IV. Survival for responders and non-responders revealed significant differences (p less than 0.05), 87% for 28 responders and 48% for 24 non-responders.

  4. Learning mechanisms in multidisciplinary teamwork with real customers and open-ended problems

    NASA Astrophysics Data System (ADS)

    Heikkinen, Juho; Isomöttönen, Ville

    2015-11-01

    Recently, there has been a trend towards adding a multidisciplinary or multicultural element to traditional monodisciplinary project courses in computing and engineering. In this article, we examine the implications of multidisciplinarity for students' learning experiences during a one-semester project course for real customers. We use a qualitative research approach and base our analysis on students' learning reports on three instances of a project course titled Multidisciplinary working life project. The main contribution of this article is the unified theoretical picture of the learning mechanisms stemming from multidisciplinarity. Our main conclusions are that (1) students generally have a positive view of multidisciplinarity; (2) multidisciplinary teams enable students to better identify their own expertise, which leads to increased occupational identity; and (3) learning experiences are not fixed, as team spirit and student attitude play an important role in how students react to challenging situations arising from introduction of the multidisciplinarity.

  5. Multidisciplinary Design Optimization Techniques: Implications and Opportunities for Fluid Dynamics Research

    NASA Technical Reports Server (NTRS)

    Zang, Thomas A.; Green, Lawrence L.

    1999-01-01

    A challenge for the fluid dynamics community is to adapt to and exploit the trend towards greater multidisciplinary focus in research and technology. The past decade has witnessed substantial growth in the research field of Multidisciplinary Design Optimization (MDO). MDO is a methodology for the design of complex engineering systems and subsystems that coherently exploits the synergism of mutually interacting phenomena. As evidenced by the papers, which appear in the biannual AIAA/USAF/NASA/ISSMO Symposia on Multidisciplinary Analysis and Optimization, the MDO technical community focuses on vehicle and system design issues. This paper provides an overview of the MDO technology field from a fluid dynamics perspective, giving emphasis to suggestions of specific applications of recent MDO technologies that can enhance fluid dynamics research itself across the spectrum, from basic flow physics to full configuration aerodynamics.

  6. Implications of East Asian summer and winter monsoons for interannual aerosol variations over central-eastern China

    NASA Astrophysics Data System (ADS)

    Cheng, Xugeng; Zhao, Tianliang; Gong, Sunling; Xu, Xiangde; Han, Yongxiang; Yin, Yan; Tang, Lili; He, Hongchang; He, Jinhai

    2016-03-01

    Air quality change is generally driven by two factors: pollutant emissions and meteorology, which are difficult to distinguish via observations. To identify the contribution of meteorological factor to air quality change, an aerosol simulation from 1995 to 2004 with the global air quality model GEM-AQ/EC was designed without year-to-year changes in the anthropogenic aerosol (including sulfate and organic and black carbon) emissions over the 10-year span. To assess the impact of interannual variations of East Asian monsoon (EAM) on air quality change in China, this modeling study focused on the region of central-eastern China (CEC), a typical East Asian monsoon (EAM) region with high anthropogenic aerosol emissions. The simulation analysis showed that the interannual variability in surface aerosols over CEC was driven by fluctuation in meteorological factors associated with EAM changes. Large amplitudes of interannual variability in surface aerosol concentrations reaching 20-30% relative to the 10-year averages were found over southern CEC in summer and over northern CEC in winter. The weakened near-surface winds of EAMs in both summer and winter were significantly correlated with aerosol increases over most areas of CEC. The summer and winter monsoon changes enhance the surface aerosol concentrations with increasing trend rates exceeding 30% and 40% over the southern and northern CEC region, respectively, during the 10 years. The composite analyses of aerosol concentrations in weak and strong monsoon years revealed that positive anomalies in surface aerosol concentrations during weak summer monsoon years were centered over the vast CEC region from the North China Plain to the Sichuan Basin, and the anomaly pattern with "northern higher" and "southern lower" surface aerosol levels was distributed over CEC in weak winter monsoon years. Aerosol washout by summer monsoon rainfall exerted an impact on CEC aerosol distribution in summer; aerosol dry depositions in

  7. Spatial Reconstructions of Asian Monsoon Climate Variability Over the Past Millennium from Long Tree-Ring Records

    NASA Astrophysics Data System (ADS)

    Cook, E. R.; Anchukaitis, K. J.; Buckley, B. M.; D'Arrigo, R. D.; Jacoby, G. C.; Wright, W. E.

    2008-12-01

    We present the first spatial reconstructions of Asian monsoon climate variability over the past millennium from long tree-ring records. The reconstructions, for both the monsoon (JJA) and pre-monsoon (MAM) seasons, are based on a 534-point grid of instrumental Palmer Drought Severity Indices (PDSI) covering all of monsoon Asia and an irregular network of 312 annual tree-ring chronologies over most of the same domain. The seasonal reconstructions were initially estimated at each grid point using a local "point-by-point regression" (PPR) method that has been used successfully in reconstructing drought over North America. Different levels of predictor variable screening applied in PPR produced a 5-member ensemble of reconstructions for each season. The estimated noise level in these reconstructions was relatively high (average cross-validation R2 over the 534 grid point domain typically <0.30). In addition, the lengths of the grid point reconstructions varied over space due to the variable length tree-ring series available for use in PPR. For these reasons, each ensemble member was iteratively refined using a local variant of PPR to improve its reconstructions, with missing values imputed as necessary, to produce complete fields extending back to AD 1000 over all 534 grid point locations. An ensemble average for each season, with estimated uncertainties, was then calculated and used for analysis. The reconstructions reveal the occurrence of some persistent "megadroughts" in the past that appear to be unprecedented in the instrumental records. These megadroughts are not restricted to any particular part of "Monsoon Asia", but the ones in Southeast Asia stand out particularly strong. Comparisons made between these drought reconstructions and a companion field of SST reconstructions for the tropical Pacific back to AD 1400, based on independent tree-ring data from the American Southwest and Mexico, suggest that unusual ENSO variability is a contributor to the development

  8. Projections of Active and Break Spells of the Indian Summer Monsoon using Original and Statistical Downscaled CMIP5 GCMs

    NASA Astrophysics Data System (ADS)

    Singh, S.; Salvi, K.; Ghosh, S.; Karmakar, S.

    2014-12-01

    The dual nature of Indian monsoon system viz. south-west and the north-east is a potent advantage for Indian economy, which is mainly supported by agriculture industry. Out of these, the south-west monsoon contributes around 70% of the total annual rainfall over India and hence, forms the major source of water for agriculture. However, the south-west monsoon possesses variability on different temporal scales such as daily, intra-seasonal, annual and decadal time-scales. Among these, understanding of the intra-seasonal variability of south-west monsoon, which is characterized by spells of good/excess rainfall (active spells) and spells of less/no rainfall (break spells) over core monsoon zone in the peak monsoon months (July and August), is the most important for crop cycle planning. Long and intense active (break) spells may lead to flood (drought) and both these situations are crucial for the critical (initial) growth period of the crops and these situations may lead to reduced yield. So, accurate prediction of these events is essential for better agricultural planning. Therefore, we evaluate the ability of, General Circulation Models (GCMs) and statistically downscaled rainfall simulations at 0.5˚ resolution, to capture the intra-seasonal variability (in terms of active and break spells) revealed by observed rainfall data. We also project the duration and frequency of active and break spells with original and downscaled GCM simulations. The analysis is performed over spatially averaged rainfall time series (over core monsoon zone) for July and August, simulated with five GCMs simulations (both with original and downscaled) over historic period (1951-2005) and extreme future (RCP45, 2071-2100). Comparison results revealed that the GCMs simulations (original and downscaled) lack the skills to reproduce active/break spells shown by observed data. Both original and downscaled GCMs showed increase/decrease in active/break spells in future and changes are more in

  9. 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

  10. 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

  11. Multidisciplinary Graduate Education in Bioprocess Engineering

    SciTech Connect

    Mark A. Eiteman

    2006-04-18

    This report describes the accomplishments of the University of Georgia in establishing an academic program geared toward the emerging biobased products industry. By virtue of its strengths and structure, the University of Georgia is particularly well-suited for developing a program focused on plant- and microbial-based bioproducts, and it was in this general area that this program was developed. The program had several unique characteristics. First, we implemented a distinguished lecture series that brought outstanding scientists and engineers to our University to interact with students and share their vision of the biobased economy. Second, we offered industrially-oriented and multidisciplinary courses that provided students with a broad background on various facets of biobased business and technology. Third, we provided the students with opportunities to expand beyond the classroom by engaging in research lab rotations and industrial internships. Fourth, each student was engaged in a creative research project as led by a multidisciplinary faculty team. Throughout the implementation of these activities, we maintained a student-centered, mentoring approach to education. The most tangible outcome of this project was the graduation of two students who participated in a variety of scholarly activities, culminating in research toward the completion of a thesis and dissertation. Both research projects involved the use of microorganisms to produce industrial products from agricultural substrates via fermentation processes. The research advanced our understanding of microorganisms as used for industrial processes and products, as described in several articles published in scholarly journals and presentations made at scientific conferences (see information on pp. 14-15). Another outcome is one graduate course, Fermentation Engineering Laboratory, which is a unique experiential and multidisciplinary course. This course will be offered in the future as an elective to

  12. A multidisciplinary database for global distribution

    SciTech Connect

    Wolfe, P.J.

    1996-12-31

    The issue of selenium toxicity in the environment has been documented in the scientific literature for over 50 years. Recent studies reveal a complex connection between selenium and human and animal populations. This article introduces a bibliographic citation database on selenium in the environment developed for global distribution via the Internet by the University of Wyoming Libraries. The database incorporates material from commercial sources, print abstracts, indexes, and U.S. government literature, resulting in a multidisciplinary resource. Relevant disciplines include, biology, medicine, veterinary science, botany, chemistry, geology, pollution, aquatic sciences, ecology, and others. It covers the years 1985-1996 for most subject material, with additional years being added as resources permit.

  13. Multidisciplinary perspectives on banana (Musa spp.) domestication.

    PubMed

    Perrier, Xavier; De Langhe, Edmond; Donohue, Mark; Lentfer, Carol; Vrydaghs, Luc; Bakry, Frédéric; Carreel, Françoise; Hippolyte, Isabelle; Horry, Jean-Pierre; Jenny, Christophe; Lebot, Vincent; Risterucci, Ange-Marie; Tomekpe, Kodjo; Doutrelepont, Hugues; Ball, Terry; Manwaring, Jason; de Maret, Pierre; Denham, Tim

    2011-07-12

    Original multidisciplinary research hereby clarifies the complex geodomestication pathways that generated the vast range of banana cultivars (cvs). Genetic analyses identify the wild ancestors of modern-day cvs and elucidate several key stages of domestication for different cv groups. Archaeology and linguistics shed light on the historical roles of people in the movement and cultivation of bananas from New Guinea to West Africa during the Holocene. The historical reconstruction of domestication processes is essential for breeding programs seeking to diversify and improve banana cvs for the future.

  14. Multidisciplinary perspectives on banana (Musa spp.) domestication

    PubMed Central

    Perrier, Xavier; De Langhe, Edmond; Donohue, Mark; Lentfer, Carol; Vrydaghs, Luc; Bakry, Frédéric; Carreel, Françoise; Hippolyte, Isabelle; Horry, Jean-Pierre; Jenny, Christophe; Lebot, Vincent; Risterucci, Ange-Marie; Tomekpe, Kodjo; Doutrelepont, Hugues; Ball, Terry; Manwaring, Jason; de Maret, Pierre; Denham, Tim

    2011-01-01

    Original multidisciplinary research hereby clarifies the complex geodomestication pathways that generated the vast range of banana cultivars (cvs). Genetic analyses identify the wild ancestors of modern-day cvs and elucidate several key stages of domestication for different cv groups. Archaeology and linguistics shed light on the historical roles of people in the movement and cultivation of bananas from New Guinea to West Africa during the Holocene. The historical reconstruction of domestication processes is essential for breeding programs seeking to diversify and improve banana cvs for the future. PMID:21730145

  15. Monsoon dynamics over the past millennium on the southern-central Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Ahlborn, Marieke; Haberzettl, Torsten; Kasper, Thomas; Henkel, Karoline; Doberschütz, Stefan; Daut, Gerhard; Reinwarth, Bastian; Ju, Jianting; Wang, Junbo; Zhu, Liping; Mäusbacher, Roland

    2013-04-01

    The Tibetan Plateau has experienced abrupt climate change superimposed by a gradual weakening of the summer monsoon systems during the Holocene. Although lake sediment records from the Tibetan Plateau are considered to be particularly sensitive to climate variations a holistic picture of the spatial and temporal monsoon evolution is still lacking due to the interplay of different moisture-transporting wind systems (Indian summer monsoon, East Asian summer monsoon, Westerlies). Closing this data gap is important since the Tibetan Plateau is a key area for understanding the climate evolution and its impact on the availability of current and future water resources in Central Asia. Hence, well-dated and high-resolution records are essential to improve the understanding of the spatial and temporal monsoonal evolution. To investigate the hydrological cycle indicating past monsoon variability on the southern-central Tibetan Plateau, records of several lakes were studied along an E-W-transect including Nam Co, Tangra Yumco, Taro Co and a small lake named TT Lake. In this study, a high-resolution sediment record from TT Lake (31.10° N, 86.57° E; 4,745 m asl) was investigated to reveal monsoonal dynamics and northern hemispheric climate oscillations over the past millennium. The 9 m deep TT Lake has a surface area of ~14,500 sqm and is located ~1,500 m west and 205 m above the recent western shoreline of Tangra Yumco. Terraces of former lake level highstands indicate that the TT Lake was part of the Tangra Yumco, but the timing remains unknown. Three sediment gravity cores, obtained in 2011 and 2012, were investigated with geochemical and sedimentological methods. By now a sedimentological core description, magnetic susceptibility data, radiocarbon age determinations, XRF scanning data, and grain size data are available. Further bio-geochemical as well as magnetostratigraphic analyses are in progress. The sedimentological description of the 50 to 89 cm long cores revealed

  16. Earth's eccentricity cycles and Indian Summer Monsoon variability over the past 2 million years: Evidence from deep-sea benthic foraminifer

    NASA Astrophysics Data System (ADS)

    Gupta, Anil K.; Dhingra, Hitesh; Mélice, Jean-Luc; Anderson, David M.

    Spectral analysis of a Uvigerina proboscidea time series from DSDP Site 214 using the Lomb-Scargle method for unevenly sampled data, exhibits two dominant power peaks at 412 and 94 kyrs over the last 2 million years, which correspond to the Earth's eccentricity cycles. The results indicate that the SW monsoon varied at about 100 kyr and 400 kyr periodicities within Earth's eccentricity domain (Milankovitch range) over the past 2 million years. Wavelet transform analysis reveals the non-stationary nature of monsoon upwelling over this interval. The amplitude of the 400 kyr cycle in the U. proboscidea time series began to increase at ∼900 kyrs as has also been observed in few recent studies. We do not see a strong relation between eccentricity highs and intense summer monsoons over the studied interval.

  17. A Study on the Influence of the Land Surface Processes on the Southwest Monsoon Simulations using a Regional Climate Model

    NASA Astrophysics Data System (ADS)

    Srinivas, C. V.; Bhaskar Rao, D. V.; Hari Prasad, D.; Hari Prasad, K. B. R. R.; Baskaran, R.; Venkatraman, B.

    2015-10-01

    Influence of the land surface processes as an important mechanism in the development of the Indian Summer Monsoon is studied by performing simulations with a regional atmospheric model. Seasonal scale simulations are conducted for two contrasting summer monsoons (MJJAS months) in 2008 & 2009 with the Weather Research and Forecasting-Advanced Research regional model at a high resolution of 15 km using the boundary conditions derived from the National Centers for Environmental Prediction (NCEP) reanalysis data and using the NOAH land surface parameterization scheme. Simulations are evaluated by comparison of precipitation with 0.5° India Meteorological Department gridded rainfall data over land, atmospheric circulation fields with 1° resolution NCEP global final analysis, and surface fluxes with 0.75° resolution Era-Interim reanalysis. Results indicated significant variation in the evolution of the surface fluxes, air temperatures and flux convergence in the 2 contrasting years. A lower albedo, higher heating (sensible, latent heat fluxes), higher air temperatures, stronger flow and higher moisture flux convergence are noted over the subcontinent during the monsoon 2008 relative to the monsoon 2009. The simulated surface fluxes are in good comparison with observations. The stronger flow in 2008 is found to be associated with stronger heat flux gradients as well as stronger north-south geopotential/pressure gradients. The simulations revealed notable differences in many features such as zonal and meridional surface sensible heat gradients which, in turn, influenced the low-level pressure gradients, wind flow, and moisture transport. The present study reveals that, even at a regional scale, the physical processes of land-surface energy partitioning do influence the regional behavior of the monsoon system to a certain extent.

  18. ITCZ and ENSO pacing on East Asian winter monsoon variation during the Holocene: Sedimentological evidence from the Okinawa Trough

    NASA Astrophysics Data System (ADS)

    Zheng, Xufeng; Li, Anchun; Wan, Shiming; Kao, Shuhji; Kuhn, Gerhard

    2016-04-01

    Deep-sea fan sediments provide an excellent geological archive for paleoenvironment reconstruction. Grain size, clay mineral and elemental (Ti, Fe, Ca) compositions were measured for a core retrieved from a submarine fan in the Okinawa Trough. Varimax-rotated Principal Component Analysis (V-PCA) on time-evolution of grain size spectrum reveals that, since the Holocene, sediment was transported mainly by the benthic nepheloid layer (33%) and upper layers (33%) which is driven by the East Asian winter monsoon (EAWM). The intensification of the Kuroshio Current during the Holocene, masks the fluvial signal of the summer monsoon and obstructs clay minerals derived from the Yellow River, a major contributor prior to 12 ka BP. A new grain size index (GSI), which represents the EAWM well, exhibits a negative correlation with the δ18O record in Dongge Cave, China during the Holocene when sea level was relatively steady. This anticorrelation suggests the southward migration of the Intertropical Convergence Zone (ITCZ). The consistency among our records and rainfall records in Peru, Ti counts in the Cariaco Basin, monsoon records in Oman and the averaged summer insolation pattern at 30°N further support the ITCZ's impact on monsoon systems globally. Cross-Correlation Analyses for GSI and log(Ti/Ca) against δ18O record in Dongge Cave reveal a decoupling between the East Asian winter and summer monsoon during 5500-2500 cal yr BP, with greater complexity in the last 2500 years. This can be attributed to exacerbated ENSO mode fluctuations and possibly anthropogenic interference superimposed on insolation and ITCZ forcing.

  19. The resolution sensitivity of the South Asian monsoon and Indo-Pacific in a global 0.35° AGCM

    NASA Astrophysics Data System (ADS)

    Johnson, Stephanie J.; Levine, Richard C.; Turner, Andrew G.; Martin, Gill M.; Woolnough, Steven J.; Schiemann, Reinhard; Mizielinski, Matthew S.; Roberts, Malcolm J.; Vidale, Pier Luigi; Demory, Marie-Estelle; Strachan, Jane

    2016-02-01

    The South Asian monsoon is one of the most significant manifestations of the seasonal cycle. It directly impacts nearly one third of the world's population and also has substantial global influence. Using 27-year integrations of a high-resolution atmospheric general circulation model (Met Office Unified Model), we study changes in South Asian monsoon precipitation and circulation when horizontal resolution is increased from approximately 200-40 km at the equator (N96-N512, 1.9°-0.35°). The high resolution, integration length and ensemble size of the dataset make this the most extensive dataset used to evaluate the resolution sensitivity of the South Asian monsoon to date. We find a consistent pattern of JJAS precipitation and circulation changes as resolution increases, which include a slight increase in precipitation over peninsular India, changes in Indian and Indochinese orographic rain bands, increasing wind speeds in the Somali Jet, increasing precipitation over the Maritime Continent islands and decreasing precipitation over the northern Maritime Continent seas. To diagnose which resolution-related processes cause these changes, we compare them to published sensitivity experiments that change regional orography and coastlines. Our analysis indicates that improved resolution of the East African Highlands results in the improved representation of the Somali Jet and further suggests that improved resolution of orography over Indochina and the Maritime Continent results in more precipitation over the Maritime Continent islands at the expense of reduced precipitation further north. We also evaluate the resolution sensitivity of monsoon depressions and lows, which contribute more precipitation over northeast India at higher resolution. We conclude that while increasing resolution at these scales does not solve the many monsoon biases that exist in GCMs, it has a number of small, beneficial impacts.

  20. Evaluation of the Indian monsoon generated by four regional climate models during the period 1981-2000

    NASA Astrophysics Data System (ADS)

    Lucas-Picher, P.; Christensen, J.; Kumar, P.; Saeed, F.; Asharaf, S.; Wiltshire, A.; Ahrens, B.; Hagemann, S.

    2010-09-01

    The EU project Water and Global Change (WATCH) is coming to an end. The main objectives of this project are to analyze, quantify and predict the components of the current and future global water cycles and evaluate their uncertainties. As part of this project, regional climate model (RCM) simulations over Europe and South Asia were generated to feed several different hydrological models. This work presents the results of 4 different RCMs over South Asia driven with ERA-40 reanalysis. The analysis focuses on the ability of the RCMs to simulate the Indian monsoon. Generally, the RCMs are able to simulate the characteristics and processes of the Indian monsoon. The better definition of the topography, due to the higher horizontal resolution, allows RCMs to develop a spatial distribution of precipitation, which is closer to the observation than for ERA40. However, at the regional scale, many differences between the RCM simulations can be observed. The RCMs are in general too warm in Northern India and this has an impact on the large scale circulation as shown by the wind spatial distribution. Using a precipitation index to determine the monsoon onset and withdrawal, the RCMs are able to determine well the beginning of the monsoon but have more difficulties capturing the end of the monsoon season compared with observations. While the spatial distribution of precipitation shows some mismatches with observations, the annual cycle of the water budget over 5 basins compares well with observations. Finally, the assessment of added value, investigated using a spatial filter, shows similar small scales features between the RCMs.

  1. Quaternary Indus River Terraces as Archives of Summer Monsoon Variability

    NASA Astrophysics Data System (ADS)

    Jonell, Tara N.; Clift, Peter D.

    2013-04-01

    If we are to interpret the marine stratigraphic record in terms of evolving continental environmental conditions or tectonics, it is essential to understand the transport processes that bring sediment from mountain sources to its final marine depocenter. We investigate the role that climate plays in modulating this flux by looking at the Indus River system, which is dominated by the strong forcing of the Asian monsoon and the erosion of the western Himalaya. Lake, paleoceanographic, and speleothem records offer high-resolution reconstructions of monsoon intensity over millennial timescales. These proxies suggest the monsoon reached peak intensity at ~9-10 ka in central India, followed by a steady decline after ~7 ka, with a steep decline after 4 ka. New lake core records (Tso Kar and Tso Moriri), however, suggest a more complex pattern of monsoon weakening between 7-8 ka in the Greater Himalayan region, which contrasts with a time of strong monsoon in central India. This indicates that the floodplains of the major river systems may not experience the same climatic conditions as their mountain sources, resulting in different geomorphologic responses to climate change. Earlier research has established that the northern part of the Indus floodplain adjacent to the mountains experienced incision after ~10 ka. Incision and reworking is even more intense in the Himalayas but its timing is not well-constrained. High altitude river valleys, at least north of the Greater Himalaya, appear to be sensitive to monsoon strength because they lie on the periphery of the Himalayan rain shadow. These valleys may be affected by landslide damming during periods of strong monsoonal precipitation, such as slightly after the monsoon maximum from 9-10 ka. Damming of these river valleys provides sediment storage through valley-filling and later sediment release through gradual incision or dam-bursting. Terraces of a major tributary to the Indus, the Zanskar River, indicate valley

  2. The Multi-Disciplinary Graduate Program in Educational Research. Final Report, Part II; Methodoloqical Trilogy.

    ERIC Educational Resources Information Center

    Lazarsfeld, Paul F., Ed.

    Part two of a seven-section, final report on the Multi-Disciplinary Graduate Program in Educational Research, this document contains discussions of quantification and reason analysis. Quantification is presented as a language consisting of sentences (graphs and tables), words, (classificatory instruments), and grammar (rules for constructing and…

  3. Impacts of Urbanization on Indian Summer Monsoon Rainfall

    NASA Astrophysics Data System (ADS)

    Shastri, H. K.; Ghosh, S.; Karmakar, S.

    2013-12-01

    Rapid urbanisation all around the world is a matter of concern to the scientific community. The fast growing urban areas carries out huge anthropogenic activities that burdens natural environment and its resources like air-water quality and space, thus have different climatology to their rural surroundings. World Urbanization Prospects 2005 annual report described 20th century as witnessing a rapid urbanization of the world's population. Though urbanization is a worldwide phenomenon, it is especially prevalent in India, where urban areas have experienced an unprecedented rate of growth with level of urbanization increased from 17.23 % to 31.16% in year 1951 to 2011and the number of cities with population more than one million has grown from 5 to 53 over the same time. We take up an observational study to understand influence of urbanisation on mesoscale circulations and resulting convection, thus nature of precipitation around urban areas. The spatially distributed analysis of gridded daily precipitation data over the country is carried out to identify nature of trends in selected statistics of Indian summer monsoon precipitation and examine its association with urban land cover to have an impact on precipitation statistics. We evaluate explicit changes around urban land use in context of 40 large Indian urban areas. Further we assess local-urban climatic signals in the point level rainfall observations with model based analysis of two nearby locations under similar climatic conditions but differing largely in terms of urbanisation. The results of gridded data analysis indicate an overall tendency towards decrease in mean precipitation however, rainfall activities are enhanced around urban areas across different climate zones of the country. Though trends observed in selected climatic parameters revealed great degree of spatial inter variability in selected precipitation statistics over the country, they accounts a greater degree of inclination for occurrence under