Search Results

You are looking at 151 - 160 of 3,503 items for :

  • Journal of the Atmospheric Sciences x
  • All content x
Clear All
Barry H. Lynn, Alexander P. Khain, Jian Wen Bao, Sara A. Michelson, Tianle Yuan, Guy Kelman, Daniel Rosenfeld, Jacob Shpund, and Nir Benmoshe

with the 1D SST model, only the initial SSTs at 0000 UTC 21 August were used, and the SSTs were calculated thenceforth using the 1D model. The lapse rate below the mixed layer was 0.14 K m −1 . The configuration of the initial aerosol distributions is shown in Fig. 5 . The design of the aerosol distribution over the computational area in Exp. 1 is presented in Fig. 5a . In Exp. 1, high aerosol concentration was assumed over land (continental aerosols) and low aerosol concentration over the ocean

Full access
A. Khain, B. Lynn, and J. Dudhia

substantially the microphysical and dynamical structure of clouds. The role of giant CCN may be significant in the central zone of TC and will be investigated in a future study. Note that there are some uncertainties with regard to the concentration and size distributions of continental AP that may form over the land under strong winds. A concentration of 3000 cm −3 (instead of 1500 cm −3 used) seems also to be realistic. In this sense our simulations can be considered as a sensitivity study of TCs to

Full access
Roni Avissar, Edwin W. Eloranta, Kemal Gürer, and Gregory J. Tripoli

resolutions as small as 1 m have been used for specific applications ( Nicholls et al. 1993 ). Mason (1994) provided a critical review of this modeling technique, and following the work of Deardorff (1972) , a few other LES models were developed (e.g., Moeng 1984 ; Schmidt and Schumann 1989 ; Hadfield et al. 1991a ; among others). Most LES studies focused on the statistical properties and the structure of turbulence in the convective boundary layer (CBL) that develops in homogeneous land (e

Full access
Craig H. Bishop, Carolyn A. Reynolds, and Michael K. Tippett

additional observation. Through the iterative use of this facility, effective global observing networks were designed. These networks were found to be considerably superior to observing strategies such as land-based observations, equally spaced observations or storm-track-based observations. Nine effective radiosonde column observations (27 in total) rendered globally averaged 12-h forecast error variance less than radiosonde observation error variance. We find it interesting to compare this result

Full access
Germán Martínez, Francisco Valero, and Luis Vázquez

similarity models, which need simulated ground temperature and in situ wind and temperature measurements at the first meters ( Sutton et al. 1978 ; Tillman et al. 1994 ; Larsen et al. 2002 ; Martinez et al. 2009 ). They all use surface layer similarity theory; therefore, only Martian surface layer (MSL) parameters are calculated, except for the mixed layer height. Large-eddy simulation (LES) models form the third kind of papers ( Rafkin et al. 2001 ; Michaels and Rafkin 2004 ; Toigo et al. 2003

Full access
Albert Hertzog, Gillian Boccara, Robert A. Vincent, François Vial, and Philippe Cocquerez

depends strongly on the quantiles in (3) ; one could, for instance, use the 80% percentile rather than p 0.9 , which would increase ε 2 . What stands out from the two maps in Fig. 8 is that the most intermittent sources, associated with the lowest probability of observation, are found above mountainous areas, such as the Antarctic Peninsula, the Ellsworth Range, and the Antarctic coast in several places, including Adélie Land. In contrast, the probability of observing gravity waves is largest, and

Full access
T. Karl, P. K. Misztal, H. H. Jonsson, S. Shertz, A. H. Goldstein, and A. B. Guenther

during RF3, RF6, and RF7 are highlighted in separate panels. These flight tracks are plotted on a map that shows two habitats from the Gap Analysis Program (GAP) land cover database used by the California Air Resources Board (CARB). The primary (i.e., homogeneous) oak habitats comprised blue, coastal, and valley oak woodlands. Heterogeneous oak areas were using three other habitats from the GAP database, which included foothill pine, montane hardwood, and conifer woodlands that contain oaks as

Full access
Qingfang Jiang

strong diurnal signal over land can propagate several hundreds of kilometers over adjacent oceans. Mapes et al. (2003) examined diurnal variations of 800-hPa temperature anomalies over the tropical area of the eastern Pacific using mesoscale model simulations. Diurnal wavelike temperature anomalies were found between 0°–3°S and 5°–7°N and were believed to have played a role in triggering offshore convection systems. These signals propagated offshore at approximately 15 m s −1 while slowly decaying

Full access
Thirza W. van Laar, Vera Schemann, and Roel A. J. Neggers

increased. 4. Results: Exploring the variability The 146 LESs produce a large amount of data with considerable variability. First, some average properties and individual days will be studied. The findings based on a subset of the data will guide a more thorough analysis using the complete dataset in the next section. a. Averaged mean state In the average cloud fraction of all simulated days ( Fig. 3a ) some typical features in the vertical structure for diurnal cycles of shallow cumulus over land can be

Full access
Dean D. Churchill and Robert A. Houze Jr.

Monsoon Experiment (WMONEX) are used to study cloud clusters that occurred over the South China Sea on 10 December 1978. These clusters underwent life cycles in which they began as groups of intense convective cells and then developed into mesoseale systems consisting partly of convective cells and partly of stratiform precipitation. In the cellular regions of clusters, ice particle concentrations (at the 8 kin, or -17-C, level) were found to be of the order of hundreds per liter

Full access