Search Results

You are looking at 81 - 90 of 9,445 items for :

  • North America x
  • Monthly Weather Review x
  • All content x
Clear All
Klaus Weickmann

1. Introduction During northern winter, global mountain torque ( τ M  ) anomalies are produced by synoptic-scale wave trains that disperse energy across Asian and North American topography ( Iskendarian and Salstein 1998 ; Weickmann et al. 2000 , hereafter WRP). The wave trains tap preexisting, high-latitude sea level pressure (SLP) anomalies and drive them southward, east of the mountains, as the wave trains' centers amplify aloft. On average, these events are short-lived and typically

Full access
Hai Lin, Gilbert Brunet, and Jacques Derome

determines the seasonal predictability is the magnitude of the signal relative to that of the noise (signal-to-noise ratio). The signal-to-noise ratio is normally high in the tropics where most GCMs produce skillful seasonal forecasts. In the extratropical regions, however, only a limited skill is expected even with a perfect numerical model due to a weak forced signal and strong noise level. Most of the forecast skill is found in the North Pacific and North American regions, a skill that is linked to

Full access
Sergio Reyes and Daniel L. Cadet

M^Y1988 SERGIO REYES AND DANIEL L. CADET 1175The Southwest Branch of the North American Monsoon during Summer 1979 SERGIO REYESCentro de Investigaci6n Cient[fica y de Educaci6n Superior de Ensenada, Ensenada, B.C.N., M~xico DANIEL L. CADETLaboratoire de Mdtdorologie Dynamique du CNRS, Ecole Polytechnique, Palaiseau, France(Manuscript received 20 April 1987, in final form 3 December 1987)ABSTRACT

Full access
Maocang Tang and Elmar R. Reiter

VOLUME 112 MONTHLY WEATHER REVIEW APRIL 1984Plateau Monsoons of the Northern Hemisphere: A Comparison between North America and Tibet MAOCANG TANGl AND ELMAR R. REITERDepartment of Atmospheric Science, Colorado State University, Fort Collins, CO 80523(Manuscript received 22 August 1983, in final form 4 January 1984)ABSTRACT Detailed analyses are presented of the temperature and pressure

Full access
R. A. Madden

JANUARY 1977 R. A. M A D D E N 9Estimates of the Autocorrelations and Spectra of Seasonal Mean Temperatures over North America R. A.National Center for Atmospheric Research,~ Boulder, Colo. 80307(Manuscript received 10 September 1976, in revised form 20 October 1976) ABSTRACT Lag one-year autocorrelations and spectra for summer and

Full access
Lynn A. McMurdie and Brian Ancell

1. Introduction North Pacific storms impact the west coast of North America, from California to southeast Alaska, and bring strong winds, precipitation, and large mountain snowfall that result in significant societal and economic impacts. The success of numerical forecasts of these storms can vary widely, from highly accurate prediction of storm location and intensity to storm position errors on the order of hundreds of kilometers and intensity errors of tens of hectopascals ( McMurdie and Mass

Full access
EUGENE M. RASMUSSON

720MONTHLY WEATHER REVIEWVol. 96, No. 10ATMOSPHERIC WATER VAPOR TRANSPORT AND THE WATER BALANCE OF NORTH AMERICAII. LARGE-SCALE WATER BALANCE INVESTIGATIONSEUGENE M. RASMUSSONGeophysical Fluid Dynamics Laboratory, ESSA, Washington, D.C.ABSTRACTThe atmospheric water vapor flux divergence and certain aspects of the water balance of North America are in-vestigated, using data from the period May 1, 1958-Apr. 30, 1963.The mean vertical distribution of flux divergence is computed

Full access
N. Vigaud, M. K. Tippett, J. Yuan, A. W. Robertson, and N. Acharya

in different regions including North America ( Vigaud et al. 2017a , b , 2018 ). In the ELR method, calibration is done at the gridpoint level (i.e., a separate regression model is constructed for every location without using information from neighboring grid points). In addition, local regression relationships are prone to sampling uncertainties that can further lead to spatially noisy forecasts, hence there might be potential for improvements by including spatial information. This study thus

Free access
Eric P. James and Stanley G. Benjamin

-ARW; Skamarock et al. 2008 ). The RAPv3 uses a 954 × 835 model domain covering all of North America with a horizontal grid spacing of 13 km near the center of the domain ( Fig. 1 ). The model computational grid is a rotated latitude–longitude grid, which reduces the stretching of the horizontal grid near the edges of the domain ( Côté et al. 1993 ). The RAP has 50 hybrid vertical levels, with a model top at 10 hPa. Fig . 1. Map of North America showing the computational domains of RAP (white boundary) and

Full access
Andrew W. Robertson, Nicolas Vigaud, Jing Yuan, and Michael K. Tippett

providing a set of more physically realistic patterns ( Straus et al. 2017 ). Several regime-based methodologies have demonstrated robust identification of the leading patterns of atmospheric low-frequency behavior over the Pacific North American sector ( Robertson and Ghil 1999 ; Smyth et al. 1999 ; Straus et al. 2007 ). The weather regime methodology has been used to link both MJO and ENSO to extreme floods over the Midwest ( Robertson et al. 2015 ), and ENSO impacts over North America ( Riddle et

Open access