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Mónica Zamora Zapata, Joel R. Norris, and Jan Kleissl

), covariability effects have been ignored. In this work, we conduct a comprehensive analysis of how coastal Sc cloud dissipation time depends on initial conditions and boundary forcings, with consideration of covariability. We use a large set of 15 variables measured or derived from realistic meteorological conditions for Southern California as input to a two-column mixed-layer model (MLM) to predict dissipation time ( section 2a ). The two columns represent ocean and land conditions and allow the modeling of

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E. O. Holopainen

1596 JOURNAL OF THE ATMOSPHERIC SCIENCES VOLUME35On the Dynamic Forcing of the Long-Term Mean Flow by the Large-Scale Reynolds' Stresses in the Atmosphere E. O. HOLOPAINENDepartment of Meteorology, University of Helsinki, Finland(Manuscript received 13 February 1978, in final form 2 May 1978)ABSTRACT Two sets of independent, upper air wind statistical data for the Northern

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Isaac M. Held and Mingfang Ting

15FEBRU^RY 1990 ISAAC M. HELD AND MINGFANG TING 495Orographic versus Thermal Forcing of Stationary Waves:The Importance of the Mean Low-Level Wind ISAAC M. HELDGeophysical Fluid Dynamics Laboratory/NOAA, Princeton, New Jersey MINGFANG TINGProgram in Atmospheric and Oceanic Sciences, Princeton University, Princeton, New Jersey(Manuscript received 25 May 1989, in final form 19 September 1989

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Olivier Boucher

1. Introduction Atmospheric aerosols have a direct influence on the earth’s climate by scattering back to space a fraction of the incident solar radiation ( Charlson et al. 1991 ). One of the current problems in determining the climatic influence of aerosols is an accurate assessment of their direct radiative forcing ( Boucher and Anderson 1995 ). While large uncertainties are due to the lack of reliable data on the spatial and temporal distributions of atmospheric aerosols and their optical

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J. M. Castanheira, M. L. R. Liberato, L. de la Torre, H-F. Graf, and C. C. DaCamara

1. Introduction Since the end of the 1990s, there has been increasing observational and modeling evidence that the stratosphere does not respond passively to tropospheric forcing but instead plays an important role in driving climate and weather variability in the troposphere down to the surface (e.g., Haynes 2005 ). One of the proposed mechanisms for the way the stratosphere might affect the tropospheric circulation is via Rossby wave propagation. This mechanism includes changes in the upward

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Jun-Ichi Yano and Mitchell W. Moncrieff

a cloud-system-resolving model (CRM) and a mass-flux-based convection parameterization. Their two-dimensional NAM–SCA application is a numerical counterpart of the Moncrieff (1992) analytic archetype of organized convection. Yano and Moncrieff introduced its construction in stepwise manner from a full NAM with numerical demonstrations for each step and tested its performance in conditions of steady large-scale forcing. Here, we apply time-varying large-scale forcing in order to demonstrate the

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Hock Lim and C-P. Chang

NOVEMBtS~1981 HOCK LIM AND C.-P. CHANG 2377A Theory for Midlatitude Forcing of Tropical Motions during Winter Monsoons HOCK LIM~ AND C.-P. CHANGDepartment of Meteorology, Naval Postgraduate School, Monterey, CA 95940(Manuscript received 31 March 1981, in final form 29 June 1981) ABSTRACT In order to understand the northeasterly monsoon surges and associated

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Yu Nie, Yang Zhang, Gang Chen, and Xiu-Qun Yang

1. Introduction Understanding the dynamical mechanisms of the midlatitude atmospheric circulation response to lower boundary thermal forcing is important for the seasonal and decadal prediction of midlatitude weather and associated extreme events. Observations and climate models have shown that the midlatitude eddy-driven jet exhibits an evident meridional displacement in response to lower boundary thermal forcing, such as the tropical SST warming during El Niño ( Seager et al. 2003 ; Lu et al

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Philip D. Thompson

15 JULY 1986PHILIP D. THOMPSON1517Probability Distribution of Modal Amplitudes in Interacting Triads with Arbitrary Random Forcing PHILIP D. THOMPSONNational Center for Atmospheric Research,* Boulder, CO 80307(Manuscript received 7 October 1985, in final form 12 February 1986)ABSTRACT This paper deals with a statistical-mechanical approach to the problem of calculating the statistics of randomlyforced triads of modes in the two-dimensional flow of a viscous fluid. We first

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Ngar-Cheung Lau and Eero O. Holopainen

VOL. 41, NO. 3 JOURNAL OF THE ATMOSPHERIC SCIENCES I FEBRUARY 1984Transient Eddy Forcing of the Time-Mean Flow as Identified by Geopotential Tendencies NGAR-CHEUNG LAUGeophysical Fluid Dynamics Program, Princeton University, Princeton, NJ 08540 EERO O. HOLOPAINENDepartment of Meteorology, University of Helsinki, 00100 Helsinki 10, Finland(Manuscript received 13 June 1983, in final form 11 October

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