I INTRODUCTION Fsf
Quasi-equilibrium QE convective closures for the relation between moist convection and large-scale dynamics originally proposed by Arakawa and Schubert 1974 assert that convective ensembles at scales smaller than the Reynolds average sub-Reynolds scales act to remove convective instability within the vertical column conditional instability of the first kind . The convective motions thus tend to establish a statistical equilibrium between the variables that affect parcel buoyancy, i.e., the...
Info Ubl
is sketched only briefly at the end of the main body of HA's paper In treating the intersections of the coordinate surfaces with the lower boundary, we have introduced massless layers along the lower boundary of the model This makes it difficult to define the surface air temperature Determining a sufficiently smooth distribution of the surface temperature is important in obtaining a sufficiently smooth distribution of the Montgomery potential, M . With the discrete hydrostatic equations almost...
X The Progress Achieved
As background for a look to follow into the gain in the time validity of the precipitation forecasts, Fig. 12a shows equitable threat scores for Eq. Threat t 24h fcst Valid 1 Jan 97-31 Dec 97 0.50 0.75 1.00 20672 11205 6554 THRESHOLD IN TOTAL OBS PTS ETA 80 KM GRID 0.50 0.75 1.00 20672 11205 6554 THRESHOLD IN TOTAL OBS PTS ETA 80 KM GRID Eq. Threat Valid 1 Jan 97 - 31 Dec 97 0.01 0.10 0.25 0.50 0.75 130902 76253 43216 20970 11370 THRESHOLD IN
Entropy the Lorenz Energy Cycle and Climate 1
Space Science and Engineering Center and Department of Atmospheric and Oceanic Sciences University of Wisconsin and Division of Earth Sciences Universities Space Research Association Columbia, Maryland II. Global Thermodynamics and Monsoonal Circulations III. A Historical Perspective Concerning Entropy and Caratheodory's Statement of the Second Law IV. The Classical Concept of the Carnot Cycle and the Driftless Climate State V. The Climate State and the Reversible Component of Total Energy...
Iv The Classical Concept Of The Carnot Cycle And The Driftless Climate State
As a point of departure, the purpose in this section is to relate entropy, its balance, and energy dissipation within the driftless climate state to the classic Carnot cycle. Many texts discuss the Carnot cycle when introducing thermodynamics e.g. Sears, 1953 Godske et al., 1957 Carrington, 1994 in which heat is added and removed isothermally at two different temperatures with intermediate stages of adiabatic contraction and expansion. Goody 1995 notes the need to understand the entropy balance...
Rh
Figure 15 A schematic illustration of the equilibrium, large-scale forcing and adjustment in an idealized T - RH B space, where T is the mean lapse rate, rd is the dry-adiabatic lapse rate, rm is the moist-adiabatic lapse rate, RH B is the relative humidity of the PBL, A 0 represents the marginal moist-convective instability defined in step 2 in the text, which is the destination of the adjustment. Step 1 and step 2 define the direction and rate of the adjustment, respectively, responding to...
Iii The New Ncep Climate Model
At NCEP, a climate model provides guidance to seasonal and long-term climate prediction. The current operational climate model is based on a substantially older version of the operational medium-range forecast MRF model. A new initiative is under way with collaborative efforts between the Environmental Modeling Center and the Climate Prediction Center to develop a new generation climate model starting from the latest version of the operational MRF model. The new climate model dynamics is...
Vi Global Modeling The Pole Problem
A review paper with topics as covered so far would do no justice to the field without a reference to the pole problem of the Arakawa-like approach. Fourier filtering with the latitude-longitude grid is not only obviously wasteful in terms of the excessive number of grid points carried in polar regions, but is also in conflict with the basic premise of the Arakawa approach of doing no artificial filtering at small scales at which the presumably important physical parameterizations are performed....
V The Eta Model An Arakawa Approach Story
The so-called Eta model is a limited-area model with the numerical formulation designed following the Arakawa principles. It has been used so far primarily for weather forecasting, so one could question the appropriateness of covering it within the symposium carrying the general circulation model GCM development title. My reasons for finding this appropriate are twofold. The first is that nowadays limited-area models are increasingly used as integral parts of general circulation models for...
Iii Climate Sensitivity
In 1979 the president's science advisor requested the National Academy of Science to study the carbon dioxide and climate issue. This resulted in the famous Charney 1979 report from a group of climate researchers, including Akio Arakawa, who met at Woods Hole in the summer of 1979. Jule Charney, the panel chairman, decided to focus on a well-defined question If the amount of atmospheric COz were doubled, how much would the global average temperature increase by the time the system came to a new...
Acknowledgments 1
I am grateful for a series of letters from Norman Phillips over the past several years. In this correspondence, he clearly presented his scientific experiences at Chicago, Princeton, and Stockholm. I gained perspective on the experiment by meshing these personal reminiscences with his scientific contributions and the wealth of information contained in Phillips's oral history interview. Tony Hollingsworth and colleagues Akira Kasahara, Joseph Tribbia, and Warren Washington are congratulated for...
Contributors
Numbers in parentheses indicate the pages on which the authors' contributions begin. Akio Arakawa 1, 539, and 721 , Department of Atmospheric Sciences, University of California, Los Angeles, California 90095 Chia Chou 457 , Department of Atmospheric Sciences and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California 90095 Paul N. Edwards 67 , School of Information, University of Michigan, Ann Arbor, Michigan 48109 Kerry Emanuel 225 , Program in...
A Personal Perspective on the Early Years of General Circulation Modeling at
II. Early History of Numerical Modeling of the Atmosphere 2 B. The Epoch-Making First Phase 1950-1960 6 III. AA's Personal Pre-UCLA History 8 IV. The Arakawa Jacobian 13 V. Development of the Mintz-Arakawa Model 18 VI. Second Phase of Numerical Modeling of the Atmosphere and the Evolution of Different Generations of the UCLA GCM 21 A. The Magnificent Second Phase 1960-1990 21 B. Evolution of Different Generations of the UCLA GCM 22 VII. Vertical Differencing in the UCLA GCM 25 A. Background...
Solving Problems with GCMs General Circulation Models and Their Role in the
Michael Ghil and Andrew W. Robertson I. Introduction The Modeling Hierarchy 285 B. Ocean and Coupled Modeling 289 C. Dynamical Systems Theory 290 II. Intraseasonal Oscillations Their Theory A. Extratropical Oscillations Observations and Theory 292 B. GCM Simulations and Their Validation 296 III. El Nino-Southern Oscillation, from the Devil's Staircase to Prediction 299 A. ENSO's'Regularity and Irregularity 299 B. The Devil's Staircase across the Modeling Hierarchy 301 C. Regularity and...
V Development Of The Mintz Arakawa Model
After finishing the derivation of the Arakawa Jacobian in late 1961, I began to work on designing dynamics for the primitive equation model. Influenced by the successful work of Phillips 1956 , and for economic reasons, a two-level model excluding the stratosphere was an almost obvious choice. Yet developing a primitive equation model for a global domain with surface topography was an extremely challenging task in many ways. For the vertical coordinate, we chose the a coordinate proposed by...
REFERENCES Eyk
Andersson, E., J. Pailleux, J.-N. Thepaut, J. R. Eyre, P. McNally, G. A. Kelly, and P. Courtier 1993 . Use of radiances in 3D 4D variational data assimilation. In Workshop Proc. on Variational Assimilation, with Special Emphasis on Three-Dimensional Aspects, pp. 123-156. European Centre for Medium-Range Weather Forecasts, Shinfield Park, Reading, UK. Anthes, R. A. 1972 . Development of asymmetries in a three-dimensional numerical model of the tropical cyclone. Mon. Wea. Rev. 100, 461-476....
REFERENCES Hqq
Arakawa, A. 1966 . Computational design for long-term numerical integration of equations of fluid motion Two dimensional incompressible flow. Part 1. J. Comput. Phys. 1,119-143. Arakawa, A. 1972 . Design of the UCLA general circulation model. In Numerical Simulation of Weather and Climate, Tech. Rep. 7. Department of Meteorology, University of California, Los Angeles. Arakawa, A. 1988 . Finite-difference methods in climate modeling. In Physically-Based Modelling and Simulation of Climate and...
ACKNOWLEDGMENTS Ins
This review is condensed from manuscript versions of Neelin and Zeng 2000 , Zeng et al. 2000 , and Lin et al. 2000 , and was presented by the lead authors as an invited talk and poster at the Symposium on General Circulation Model Development Past, Present, and Future, held at UCLA, January 20-22, 1998. Conversations with A. Adcroft, A. Arakawa, C. Bretherton, C. Cassou, R. Dickinson, P. Dirmeyer, K. Emanuel, R. Koster, K.-N. Liou, C. R. Mechoso, C. Perigaud, D. A. Randall, R. Seager, J....
Ix Hurricane Tracks
Still another indication of the benefits from emphasizing a large model domain of uniform resolution, and an Arakawa-style design, may be the Eta performance in forecasting tracks of major 1996 Atlantic hurricanes in comparison with that of models employing two competing concepts Mesinger, 1998b . Successful Eta performance in forecasting tracks of various hurricanes, tropical storms, or Pacific tropical cyclones was already noted early in the developmental work on the model e.g., Kerr, 1990,...
Vii A Threedimensional Version Of The Model With An Isentropic Vertical
Hsu and Arakawa 1990 hereafter HA discussed the many advantages of the isentropic vertical coordinate for numerical modeling of the large-scale circulation of the atmosphere. These advantages include the following Drastic reduction of the numerical difficulties associated with vertical advection Figure 5 The simulated January-mean boundary-layer wind streamlines and precipitation field obtained in a simulation using a geodesic grid and the a coordinate, with an embedded variable-depth boundary...
SCEP and SMIC
With the rise of the environmental movement in the early 1970s came early interest in world-scale environmental problems. Two important stud ies, both prepared as input to the 1972 United Nations Conference on the Human Environment, noted the possibility of inadvertent climate modification. The Study of Critical Environmental Problems SCEP focused on pollution-induced changes in climate, ocean ecology, or in large terrestrial ecosystems. It cited GCMs as indispensable in the study of possible...
Info Olx
Figure 1 January-mean SST simulated using the a Katayama and b Harshvardhan long-wave radiation schemes. Values shown correspond to results 1 year after the integrations were started from identical initial conditions. Contour interval is 2 C. Values greater than 28 C are shaded. ture gradient along the equator is maintained throughout the year and has realistic values. We will return to this point in Section III.A of this chapter. The experiment also simulates a realistic seasonal evolution of...
Foreword
The volume you now hold in your hands is not the usual collection of miscellaneous papers from an office drawer, hastily collected by friends anxious to honor an admired and respected fellow scientist. Instead, this book consists of papers especially prepared for presentation at the January 1998 Arakawa Retirement Symposium. This favors us with substantial and appreciative assessments of Akio Arakawa's contributions and their applications. But we also have his personal account of how he...
Iii A Historical Perspective Concerning Entropy And Caratheodorys Statement Of
In his discussions of thermodynamic systems, Sommerfeld 1950, 1964, pp. 26-86 emphasizes that there are two parts to the second law. For the first part he states that all thermodynamic systems possess a property which is called entropy. It is calculated by imagining that the state of the system is changed from an arbitrarily selected reference state to the actual state through a sequence of states of equilibrium and by summing up the quotients of the quantity of heat introduced at each step and...
Mssa Mode 1
Figure 10 Percentage of variance explained by the leading 10 M-SSA modes of the simulated equatorial Pacific SST. learned that SSTs simulated by the CGCM are extremely sensitive to the formulation of interacting physical processes, especially in the atmospheric component of the CGCM. For example, a relatively modest change in the long-wave radiation scheme can produce a drastically different mean SST. These sensitivities reflect the fact that the surface fluxes are consequence of complicated...
Ucla Arakawa Global Circulation
Arakawa, A. 1957a . On the maintenance of zonal mean flow. Pap. Met. Geophys., 8, 39-54. Arakawa, A. 1957b . On the mean meridional circulation in the atmosphere J. Meteor. Soc. Japan, 75th Anniversary Volume, 230-236. Arakawa, A. 1958 . Modern theory of general circulation of the atmosphere. Kisho Kenkyu Note, 9, No. 4, Meteor. Soc. Japan in Japanese . Arakawa, A. 1961 . The variation of general circulation in the barotropic atmosphere J. Meteor. Soc. Japan, 39, 49-58. Arakawa, A. 1962 ....
Akio Arakawa
Department of Atmospheric Sciences University of California, Los Angeles, California II. Early History of Numerical Modeling of the Atmosphere III. AA's Personal Pre-UCLA History IV. The Arakawa Jacobian V. Development of the Mintz-Arakawa Model VI. Second Phase of Numerical Modeling of the Atmosphere and the Evolution of Different Generations of the UCLA GCM UCLA GCM VIII. Horizontal Differencing in the UCLA GCM IX. Formulation of PBL Processes in the UCLA GCM X. Formulation of Moist Processes...
Ii Treatment Of Cumulus Convection In Tropical Cyclone Models
In November 1960, the first international conference on numerical weather prediction was held in Tokyo. Subsequent meetings were held in Oslo in 1962 and Moscow in 1964. There, I presented a paper on a numerical experiment on the development of a tropical cyclone using a primitive equation model in which the release of the latent heat of condensation is explicitly treated Kasahara, 1961, 1962 . A similar attempt was also discussed by Syono 1962 at the conference. These were the first nonlinear...
II GENERAL CIRCULATION IDEAS AND CONTROVERSIES s TO EARLY s
To appreciate the momentous changes that took place in general circulation theory between 1940 and 1955, one has only to read Brunt's classic text Brunt, 1944, Chap. 19 , and follow this with a reading of Eady's 1957 contribution 13 years later, The General Circulation of the Atmosphere and Oceans. From Brunt, the reader is left feeling that a consistent theory of the atmosphere's general circulation is out of reach It has been pointed out by many writers that it is impossible to derive a...
Integraionen Der Atmospheren Solberg
Arakawa, A. 1958 . Modern theory of general circulation. Kisho Kenkyu 9, 4, in Japanese . Bjerknes, J. 1948 . Practical application of H. Jeffreys' theory of the general circulation. In R sum des M moires R union d'Oslo, pp. 13-14. Bjerknes, J. 1955 . The transfer of angular momentum in the atmosphere. In Sei. Proc. Int. Assoc. Meteor., pp. 407-408. Bjerknes, J., and J. Holmboe 1944 . On the theory of cyclones. J. Meteorol. 1, 1-22. Bjerknes, J., and E. Palmen 1937 . Investigations of selected...
Iv Advent Of Arakawaschubert Cumulus Parameterization
In 1968, another international symposium on numerical weather prediction was held in Tokyo. Again, its proceedings serve as a valuable historical document. Many papers were presented that demonstrated the utility of primitive equation models for studying hurricane development, simulating the general circulation of the atmosphere, and even medium-range weather forecasting as referred to earlier in Section III. In addition, active discussions took place at the symposium concerning the improvement...
REFERENCES Eha
Arakawa, A., and W. H. Schubert 1974 . Interaction of a cumulus cloud ensemble with the large-scale environment, Part I. J. Atmos. Sci. 31, 674-701. Betts, A. K. 1986 . A new convective adjustment scheme. Part I Observational and theoretical basis. Quart. J. Roy. Meteor. Soc. 112, 677-691. Bretherton, C. S., and P. K. Smolarkiewicz 1989 . Gravity waves, compensating subsidence and detrainment around cumulus clouds. J. Atmos. Sci. 46, 740-759. Brown, R. G., and C. S. Bretherton 1995 . Tropical...
Iii Treatment Of Cumulus Convection In General Circulation Models
In the mid-1960s, when research on the development of tropical cyclones was thriving, a great deal of research activity took place in the numerical simulation of atmospheric general circulation. This was stimulated by a successful experiment conducted by Phillips 1956 with a quasi-geostrophic model, but this time primitive equation models were used Lewis, 1998 . Dealing with primitive equation models having a full-blown physics package, including one for the moist physics, how did the...
Chapter Oed
A Retrospective Analysis of the Pioneering Data Assimilation Experiments with the Mintz -Arakawa General Circulation Model NASA Goddard Space Flight Center Greenbelt, Maryland School of Engineering Morgan State University Baltimore, Maryland NASA Goddard Space Flight Center Greenbelt, Maryland II. Description of Experiments III. Results of GEOS Simulation Experiments
I INTRODUCTION Esa
When Akio Arakawa graduated from Tokyo University with a B.Sc. degree in physics in 1950, the economy of postwar Japan was in a recovery phase and there were few job opportunities in physics. However, there were job opportunities in the Japan Meteorological Agency JMA and, fortunately for our field, Akio took one of them. His early duties in JMA included a stint on a weather ship during a typhoon passage and research into the synoptic meteorology of the East Asia region. These must have been...
REFERENCES Qal
Andersson, E., A. Hollingsworth, G. Kelly, P. Lonnberg, J. Pailleux, and Z. Zhang 1991 . Global observing system experiments on operational statistical retrievals of satellite sounding data. Mon. Wea. Rev. 119, 1851-1864. Andersson, E., J. N. Thepaut, J. R. Eyre, A. P. McNally, G. Kelly, P. Courtier, and J. Pailleaux 1994 . Use of cloud cleared radiances in three four dimensional variational data assimilation. Quart. J. Roy. Meteor. Soe. 120, 627-653. Andersson, E., J. Haseler, P. Unden, P....