Mesoscale circulation

Local winds. Local (mesoscale) circulations and winds such as breezes, mountain-valley circulation, slope winds, foehns, boras, etc., along with the atmospheric processes on synoptic scale, play an important role in the formation of the climate on the coasts of the Black Sea. 

Mahadevan A. and Archer D. (2000) Effect of mesoscale circulation on nutrient supply to the upper ocean. J. Geophys. Res. 105, 1209-1225. 

Atkinson BW (1981) Mesoscale atmospheric circulation. Academic Press, London... 

The mesoscale variability in the Black Sea is mostly related to the meandering of the RC, to the formation of anticyclonic eddies between the RC and the coast, to their transformation into the deep-sea eddies, and to the interaction of the latter with the neighboring anticyclonic and cyclonic circulation elements and with the RC. The meandering jet of the RC together with the... 

The use of local theories, incorporating parameters such as the eddy viscosity Km and eddy thermal conductivity Ke, has given reasonable descriptions of numerous important flow phenomena, notably large scale atmospheric circulations with small variations in topography and slowly varying surface temperatures. The main reason for this success is that the system dynamics are dominated primarily by inertial effects. In these circumstances it is not necessary that the model precisely describe the role of turbulent momentum and heat transport. By comparison, problems concerned with urban meso-meteorology will be much more sensitive to the assumed mode of the turbulent transport mechanism. The main features of interest for mesoscale calculations involve abrupt... 

Helfrich K. R. and Speer K. G. (1995) Ocean hydrothermal circulation mesoscale and basin-scale flow. Geophys. Monogr. (AGU) 91, 347-356. 

However, as advanced techniques and equipment allowed measurement on finer grids and shorter time scales, the mesoscale fluctuations were found to be much more energetic than the general circulation. The great bulk of the energy supplied to the ocean does not drive the general circulation, but rather drives the finer scale fluctuations in the ocean, with horizontal space scales of tens to several hundreds of kilometers, and time scales not of decades or years, but of many days to several months. 

The horizontal airflow in the BL often consists of synoptic-scale (> 1000 km) and mesoscale (10-1000 km) circulations, and microscale ( 1 km) turbulence. Their time scales are days, 1 to 24 h, and less than 1 h, respectively. The impact of toxic dispersion on a synoptic scale or large mesoscale is generally not threatening to health, while for small mesoscale (< 100 km) and microscale, the impact can be life threatening because of accumulated doses over a relatively small area. Small-scale... 

Fig. 5. Enlarged fragment (40 km x 50 km) of the ERS-1 SAR image obtained on May 20, 1994, at 14 20 UTC covering the area of the mesoscale cyclonic circulation east of Kuroshio boundary (copyright European Space Agency). The labels correspond to the labels in Figure lb...

V+dV] by coalescence of two smaller droplets, with the mesoscale parameter MJJ,V) the coalescence coefficient of droplets with a volume of U and V. The third and fourth terms represent the disappearance of droplets by, respectively, coalescence and breakage, while the last term expresses the exchange of droplets between the two compartments with qy as exchange flow rate. The analogous nonlinear integrodifferential equation for the circulation compartment can be obtained by interchanging the subscripts imp and circ in Eq. (10.76). The mesoscale parameters are typically obtained by correlations that can depend on the microscale properties via a dependence on, for instance, the monomer conversion (Asua, 2007). 

Bjorn B. Stevens is an associate professor in the Department of Atmospheric and Oceanic Sciences at the University of California, Los Angeles (UCLA), where he is responsible for a program of research and teaching with a focus on the role of the planetary boimdaty layer in large-scale circulations. He is also an affiliate scientist at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado, where he is working with the Climate and Global Dynamics and Mesoscale and Microscale Meteorology Divisions to imderstand and quan-... 

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