Coupling of the MM5 Regional Atmospheric Model with a Physically-based Regional Land Surface Model
Author: Daniel Chau
Publisher:
Published: 2000
Total Pages: 328
ISBN-13:
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Land - Atmosphere Coupling in Climate Models Over North America; Understanding Inter-model Differences
Author: Almudena García García
Publisher:
Published: 2020
Total Pages:
ISBN-13:
DOWNLOAD EBOOKThe interactions between the lower atmosphere and the land surface are associated with weather and climate phenomena such as the duration, frequency and intensity of extreme temperature and precipitation events. Thus, the representation of land- atmosphere interactions in climate model simulations is crucial for projecting future changes in the statistics of extreme events as realistically as possible. Given the importance of the land-atmosphere interaction, the purpose of the thesis is to evaluate climate simulations performed by General Circulation Models (GCMs) and Regional Climate Models (RCMs) and examine the role of the Land Surface Model (LSM) component and the horizontal resolution over North America. For this purpose, I analyze a large set of simulations from GCMs and RCMs used by the fifth assessment report of the Intergovernmental Panel on Climate Change (IPCC) as well as my own simulations performed by the Weather Research and Forecasting (WRF) model. Results show that GCM simulations present large uncertainties in the representation of land-atmosphere interactions in comparison with observations. This work also reveals a dependence of the simulated land-atmosphere interactions on the LSM components used in regional and global simulations. Additionally, the LSM component is identified as an important source of uncertainty in the simulation of extreme temperature and precipitation events. Increasing the horizontal resolution also affects the simulation of land-atmosphere interactions, which lead to the intensification of precipitation, evapotranspiration and soil moisture at low latitudes; that is increased latent heat flux, soil moisture, and precipitation. The impact of both factors, horizontal resolution and the LSM, is larger in summer in agreement with the summer intensification of land-atmosphere interactions reported in the literature. The comparison of model simulations and observations indicates that the use of the most comprehensive LSM component available in WRF, the Community Land Model version 4 (CLM4), leads to a better representation of temperature climatologies. In contrast, finer horizontal resolutions are associated with larger biases in the WRF simulation of precipitation climatology, due to the overestimation of precipitation in the WRF model. Due to the large effect of the LSM component on the simulation of near-surface conditions shown in this dissertation, the use of simple version of LSM component in GCMs, RCMs or reanalyses can be an important limitation in climate simulations and reanalysis products.
Development and Testing of Coupled Land-Surface, Pbl and Shallow/Deep Convective Parameterizations Within the Mm5
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
Published: 2018-06-27
Total Pages: 224
ISBN-13: 9781721938643
DOWNLOAD EBOOKThe objective of this investigation was to study the role of shallow convection on the regional water cycle of the Mississippi and Little Washita Basins using a 3-D mesoscale model, the PSUINCAR MM5. The underlying premise of the project was that current modeling of regional-scale climate and moisture cycles over the continents is deficient without adequate treatment of shallow convection. It was hypothesized that an improved treatment of the regional water cycle can be achieved by using a 3-D mesoscale numerical model having a detailed land-surface parameterization, an advanced boundary-layer parameterization, and a more complete shallow convection parameterization than are available in most current models. The methodology was based on the application in the MM5 of new or recently improved parameterizations covering these three physical processes. Therefore, the work plan focused on integrating, improving, and testing these parameterizations in the MM5 and applying them to study water-cycle processes over the Southern Great Plains (SGP): (1) the Parameterization for Land-Atmosphere-Cloud Exchange (PLACE) described by Wetzel and Boone; (2) the 1.5-order turbulent kinetic energy (TKE)-predicting scheme of Shafran et al.; and (3) the hybrid-closure sub-grid shallow convection parameterization of Deng. Each of these schemes has been tested extensively through this study and the latter two have been improved significantly to extend their capabilities. Stauffer, David R. and Seaman, Nelson L. and Munoz, Ricardo C. Goddard Space Flight Center NAG5-6398
Hydroclimatology of the Great Lakes Region of North America
Author: Julie A. Winkler
Publisher: Frontiers Media SA
Published: 2022-11-14
Total Pages: 243
ISBN-13: 2832505457
DOWNLOAD EBOOKLand-atmosphere Coupling Manifested in Warm-season Observations on the U.S. Southern Great Plains
Author:
Publisher:
Published: 2014
Total Pages: 20
ISBN-13:
DOWNLOAD EBOOKThis study examines several observational aspects of land-atmosphere coupling on daily average time scales during warm seasons of the years 1997 to 2008 at the Department of Energy Atmospheric Radiation Measurement Program’s Southern Great Plains (SGP) Central Facility site near Lamont, Oklahoma. Characteristics of the local land-atmosphere coupling are inferred by analyzing the covariability of selected land and atmospheric variables that include precipitation and soil moisture, surface air temperature, relative humidity, radiant and turbulent fluxes, as well as low-level cloud base height and fractional coverage. For both the energetic and hydrological aspects of this coupling, it is found that large-scale atmospheric forcings predominate, with local feedbacks of the land on the atmosphere being comparatively small much of the time. The weak land feedbacks are manifested by 1) the inability of soil moisture to comprehensively impact the coupled land-atmosphere energetics, and 2) the limited recycling of local surface moisture under conditions where most of the rainfall derives from convective cells that originate at remote locations. There is some evidence, nevertheless, of the local land feedback becoming stronger as the soil dries out in the aftermath of precipitation events, or on days when the local boundary-layer clouds are influenced by thermal updrafts known to be associated with convection originating at the surface. Finally, we also discuss potential implications of these results for climate-model representation of regional land-atmosphere coupling.
Physically-Based Modelling and Simulation of Climate and Climatic Change
Author: M.E. Schlesinger
Publisher: Springer Science & Business Media
Published: 2012-12-06
Total Pages: 635
ISBN-13: 9400930410
DOWNLOAD EBOOKPREFACE xv LIST OF LECTURERS xix LIST OF PARTICIPANTS xx]. VOLUME I PART I - DESIGN AND DEVELOPMENT OF PHYSICALLY-BASED MODELS OF THE ATMOSPHERE Section 1 - Introduction GATES, W. L. - Climate and the Climate System 3 SIMMONS, A. J. and L. BENGTSSON - Atmospheric General Circulation Models: Their Design and Use for Climate Studies 23 Section 2 - Numerical Methods for Large-Scale Dynamics ARAKAWA, A. - Finite-Difference Methods in Climate Modeling 79 BOURKE, W. - Spectral Methods in Global Climate and Weather Prediction Models 169 Section 3 - Parameterization of Subgrid-Scale Physical Processes FOUQUART, Y. - Radiative Transfer in Climate Models 223 LAVAL, K. - Land Surface Processes 285 SELLERS, P. J. , Y. MINTZ, Y. C. SUD and A. DALCHER - A Brief Description of the Simple Biosphere Model (SiB) 307 SOMMERIA, G. - Parameterization of the Planetary Boundary Layer in Large-Scale Atmospheric Models 331 x TABLE OF CONTENTS TIEDTKE, M. - Parameterization of Cumulus Convection in Large-Scale Models 375 SUNDQVIST, H. - Parameterization of Condensation and Associated Clouds in Models for Weather Prediction and General Circulation Simulation 433 PART II - DESIGN AND DEVELOPMENT OF PHYSICALLY-BASED MODELS OF THE OCEAN AND SEA ICE HAN, Y. -J. - Modelling and Simulation of the General Circulation of the Ocean 465 HIBLER, W. D. - Modelling Sea Ice Thermodynamics and Dynamics in Climate Studies 509 PART III - METHODS OF COUPLING ATMOSPHERE, OCEAN AND ICE MODELS BRYAN, K.
Physically-Based Modelling and Simulation of Climate and Climatic Change
Author: M.E. Schlesinger
Publisher: Springer Science & Business Media
Published: 2012-12-06
Total Pages: 472
ISBN-13: 9400930437
DOWNLOAD EBOOKThe Geo-Sciences Panel is a synonym for the Special Programme on Global Transport Mechanisms in the Geo-Sciences. This Programme is one of the special programs established by the NATO Science Committee to promote the study of a specific topic using the usual NATO structures, namely, Advanced Research Workshops, Advanced Study Institutes, Conferences, Collaborative Research Grants, Research-Studies and Lecture Visits. The aim of the Programme is to stimulate and facilitate international col laboration among scientists of the member countries in selected areas of global transport mechanisms in the Earth's atmosphere, hydrosphere, lithosphere and asthenosphere, and the interactions between these global transport processes. Created in 1982, the Geo-Sciences Panel followed the Air Sea Interactions Panel which was very successful in reviewing mechanisms at the air-sea-ice interface. Initially the Geo-Sciences Panel recognized the importance of magma chambers, ore deposits, geochemical cycles, seismic activity and hydrological studies. However, the Panel was rap idly convinced that the climate system is one of the most important sys tems in which to promote research on global transport mechanisms. Consequently, the Panel welcomed the organization of a course on Physically Based Modelling and Simulation of Climate and Climatic Change. This course was launched in Belgium in 1984 during both the Liege colloquium on Coupled Ocean-Atmosphere tlodels and the Louvain-Ia Neuve General Assembly of the European Geophysical Society. Rapidly scientists recognized that this course was timely and would be well received by the climate community, especially by junior researchers in this multi- and inter-disciplinary field.
Modeling Land-surface/atmosphere Dynamics for CHAMMP.
Author:
Publisher:
Published: 1993
Total Pages: 6
ISBN-13:
DOWNLOAD EBOOKProject progress is described on a DOE CHAMP project to model the land-surface/atmosphere coupling in a heterogeneous environment. This work is a collaboration between scientists at Iowa State University and the University of New Hampshire. Work has proceeded in two areas: baseline model coupling and data base development for model validation. The core model elements (land model, atmosphere model) have been ported to the Principal Investigator's computing system and baseline coupling has commenced. The initial target data base is the set of observations from the FIFE field campaign, which is in the process of being acquired. For the remainder of the project period, additional data from the region surrounding the FIFE site and from other field campaigns will be acquired to determine how to best extrapolate results from the initial target region to the rest of the globe. In addition, variants of the coupled model will be used to perform experiments examining resolution requirements and coupling strategies for land-atmosphere coupling in a heterogeneous environment.
Atmosphere-ocean Modeling: Coupling And Couplers
Author: Carlos Roberto Mechoso
Publisher: World Scientific
Published: 2021-07-27
Total Pages: 203
ISBN-13: 9811232954
DOWNLOAD EBOOKCoupled atmosphere-ocean models are at the core of numerical climate models. There is an extraordinarily broad class of coupled atmosphere-ocean models ranging from sets of equations that can be solved analytically to highly detailed representations of Nature requiring the most advanced computers for execution. The models are applied to subjects including the conceptual understanding of Earth's climate, predictions that support human activities in a variable climate, and projections aimed to prepare society for climate change. The present book fills a void in the current literature by presenting a basic and yet rigorous treatment of how the models of the atmosphere and the ocean are put together into a coupled system. The text of the book is divided into chapters organized according to complexity of the components that are coupled. Two full chapters are dedicated to current efforts on the development of generalist couplers and coupling methodologies all over the world.
Integrated Regional Models
Author: Peter Groffman
Publisher: Springer Science & Business Media
Published: 2012-12-06
Total Pages: 164
ISBN-13: 1468464477
DOWNLOAD EBOOKIntegrated regional models are conceptual and mathematical models that describe the physical environment, biological interactions, human decision-making, and human impact on the environment. Efforts are now being made to integrate regional models from the physical, biological and social sciences in order to respond to diverse environmental problems. This volume explores the latest research developments on processes operating at a variety of scales, including regions, and how scientists can combine their efforts to develop models linking biological, physical, and human systems. Data requirements for successful integrated regional models are identified and discussed. Chapters also consider methodological questions, such as whether to integrate disciplinary approaches at the beginning or the end of the modelling process, and whether integrated regional models should focus on specific regions or specific problems. The information in this volume will enable the reader to view problems such as coastal zone management, atmospheric pollution, non-point source pollution, commodity production in forested areas, and urban expansion in a broad, conceptual context. Researchers and graduate students in ecology, biology, geography and geology will benefit from this innovative approach to contemporary environmental problems.
