Search Results

You are looking at 41 - 50 of 752 items for :

  • Monthly Weather Review x
  • Refine by Access: All Content x
Clear All
Masaru Kunii, Kosuke Ito, and Akiyoshi Wada

(2012) . b. Data assimilation cycles with the atmosphere–ocean coupled model CNHM ( Ito et al. 2015 ) was newly implemented as a forecast model in the NHM-LETKF system. As described in the introduction, the oceanic part of CNHM is the PWP model. PWP is a very simple mixed layer model that can represent the diurnal cycle and vertical structure of the upper ocean at a fixed grid, but it is not a general circulation model. It calculates ocean temperature, salinity, and horizontal components of current

Full access
William J. Merryfield, Woo-Sung Lee, George J. Boer, Viatcheslav V. Kharin, John F. Scinocca, Gregory M. Flato, R. S. Ajayamohan, John C. Fyfe, Youmin Tang, and Saroja Polavarapu

the Southern Ocean at around 60°S tends to be somewhat too shallow in the models. Fig . 6. Ocean mixed layer depths in (left) March and (right) September based on monthly mean temperature and salinity from the (top) PHC/WOA observational climatology and 1991–2000 model climatologies from historical runs of (middle) CanCM3 and (bottom) CanCM4, computed using the algorithm of Kara et al. (2000) . Volume transports associated with various aspects of ocean circulation provide further metrics for

Full access
Richard M. Yablonsky and Isaac Ginis

, and (iii) to compare the results to an alternative data-assimilated ocean product, the daily North and Equatorial Atlantic Ocean Prediction System Best Estimate (RSMAS HYCOM, described in section 3b ). 2. Ocean initialization in the GFDL/URI coupled hurricane prediction system The starting point for the ocean initialization in any operational GFDL model forecast is the Generalized Digital Environmental Model (GDEM) monthly ocean temperature and salinity climatology ( Teague et al. 1990 ), which

Full access
Ming Ji, David W. Behringer, and Ants Leetmaa

the ocean model for CMP12: a relaxation of the OGCM’s surface salinity to the climatology of Levitus et al. (1994) is added, and a modification to the parameter ν 0 in the Richardson number–dependent vertical mixing formulation ( Pacanowski and Philander 1981 ) for the eddy viscosity coefficient. The eddy viscosity coefficient ν is given by where R i is the Richardson number and α, ν b , ν 0 , and n, are parameters to be chosen empirically. Pacanowski and Philander

Full access
Masayoshi Ishii, Masahide Kimoto, and Misako Kachi

distributed by the National Oceanographic Data Center (NODC) of the National Ocean and Atmosphere Administrations (NOAA; Levitus and Boyer 1994 ; Boyer and Levitus 1994 ). In addition, temperature and salinity climatologies have been produced by Levitus (1982) , Levitus and Boyer (1994) , and Levitus et al. (1994b) . The latest climatology covers monthly variations at depths from sea surface to 1000 m. Subsurface temperature analyses have been carried out with various approaches by several

Full access
Xiouhua Fu and Bin Wang

the simulation and the observations, particularly over the Bay of Bengal, the South China Sea, and the WNP. In the observations ( Fig. 3h ), significant negative SST anomalies developed in the above areas. This feature is totally missing in the coupled model. This inadequate simulation of SST cooling is likely due to the lack of salinity effects in the ocean model. As suggested by Lukas and Lindstrom (1991) , a salt-stratified barrier layer (which is much shallower than the mixed layer defined by

Full access
Lynn K. Shay and Eric W. Uhlhorn

(1 Sv ≡ 10 6 m 3 s −1 ) through the straits, force LC variability and modulate WCR shedding events ( Maul 1977 ; Sturges and Leben 2000 ; Leben 2005 ). The LC transports warm subtropical water with a markedly different temperature and salinity structure into the GOM compared to the GCW ( Shay et al. 1998 ). As the LC intrudes north of 25°N, WCRs with diameters of 100–200 km separate from the LC at an average interval of 6–11 months, based on radar altimeter-derived SHA fields ( Sturges and

Full access
A. T. Weaver, J. Vialard, and D. L. T. Anderson

has been exploited in the present study to neglect changes in vertical diffusion coefficients associated with perturbations in temperature, salinity, and velocity. Finally, the computational cost of 4DVAR may also be significantly reduced by computing the increments at lower resolution than that of the full model ( Rabier et al. 2000 ), although this is not an issue in our present system, which employs a relatively low resolution version of the OGCM. The purpose of this paper is to give a thorough

Full access
Eric Vanden-Eijnden and Jonathan Weare

assimilation strategies is the Kuroshio running along the eastern coast of Japan. The Kuroshio exhibits transitions between a small meander during which the current remains close to the coast of Japan, and a large meander during which the current bulges away from the coast (see Figs. 1 and 2 ). The Kuroshio’s central role in distributing heat and salinity in the surrounding region has led to many studies of its bimodal behavior beginning with a study by Yoshida in 1961 (see Yoshida 1961 ). The meanders

Full access
Clara Draper and Rolf H. Reichle

assimilation to test the impact of assimilating Advanced Scatterometer (ASCAT) and Soil Moisture Ocean Salinity (SMOS) soil moisture retrievals into a system that uses the same model, atmospheric assimilation, and suite of atmospheric observations as MERRA-2. Below, the current state of land data assimilation within the context of atmospheric modeling is briefly reviewed, to place the current study in context, and to justify the chosen land data assimilation design and approach. Currently, there are two

Full access