Westerly wind

In the latitudes occupied by the US the climate is dominated by westerly winds. The basic wind speed may be adjusted to ensure that the risk of it being exceeded is the same for all directions. This is achieved by the wind speed factor Sa. 

There is a zonal atmospheric circulation system associated with this normal ocean condition called the Walker Cell (Eig. 10-7). Evaporation rates are high over the warm pool and warm moist air ascends to great heights (deep convection) producing extensive cloud systems and rain. The Walker Cell is closed by westerly winds aloft and subsidence in the high-pressure zone of the eastern Pacific. 

Concern over air pollution has been well documented (Brimblecombe, 1978). The impacts of atmospheric chemistry on human health and the environment can be traced back many centuries, indeed some two thousand years. For example, the Mishnah Laws in Israel in the first and second centuries A.D. required that, because of the odors emitted, tanneries be located at least 30 m away from the town and only on the east side, due to prevailing westerly winds (Mamane, 1987). 

FIGURE 11.29 Ratio of measured individual compounds of NO, to total NO, at Idaho Hill, Colorado, with easterly winds (more polluted air) and with westerly winds (cleaner but more aged air), respectively (data from Williams et al., 1997). 

The cyclonic activity over the central part of the European part of Russia leads to the development of westerly winds over the Black Sea. In this case, the strongest winds are observed under the passages of deep Scandinavian cyclones over the south of the Ukraine and in the rear parts of the Mediterranean cyclones. 

In the case where a cyclone is located over the central part of the Black Sea, strong easterly and westerly winds dominate over its northern and southern parts, respectively. At this time, an anticyclone is usually located over the European part of Russia. 

Local synoptic wind impacts also favor the intensification of the horizontal water exchange in the Black Sea. For example, they cause wind effected phenomena and formation of filaments of coastal upwellings and provide the separation of coastal anticyclones from the eastern coast (under northerly winds) or removal of the shelf waters to the deep-water basin by anticyclones over the northwestern continental slope (under westerly winds). 

The information on the quantities of combusted materials, and on aerosol and elemental carbon production, which is collected in Tables II-V, has been combined in Table VI to derive the state of the atmosphere during the nuclear war. We assume that the war would last for only a few days the aerosol particles would also be given off to the atmosphere in such a short time. Most fire produced aerosol would initially be located between 30°N and 60 N, where most of the nuclear targets are located. If the nuclear explosions would occur over a period of three days, the fire plumes produced on the West and East coast of the US and over Europe (including the USSR) could cover most of the 30-60°N latitude belt, except the Pacific Ocean. This is based on an average westerly wind speed of 20 m/s in tbe middle and upper troposphere (Oort and Rasmussen, 1971). Spread in South-North direction within the latitude zone should... 

This apparent incompatibility between the theoretical and the empirical data could be reconciled by considering the water film thickness (d), which controls -29% of the growth variability. In climate systems that show alternating warm-dry and cool-wet periods, speleothem growth might be controlled alternately by the temperature and the water film thickness. Temperate maritime climates, controlled by depressions related to westerly winds and the polar front, do in fact show these extremes of climate (warm-wet or cool-dry conditions are relatively rare). In another climate system, temperature and... 

Its center lies at an altitude of about 5 km, that is, in the center of the troposphere, and is frequently located over the Baltic Sea. The location, the strength, and the cyclonic or an ticy clonic character of this j et stream determines the weather of the Baltic Sea. Two global action centers over the North Atlantic—the Icelandic Low and the Azores High—regulate its dynamics. North Atlantic lows with their fronts and wedges at intermediate altitudes are very often embedded in this westerly wind system. Usually, they move rapidly from west to east across the Baltic Sea and its coasts. 

FIGURE 4.23 Map of the western Baltic Sea. The Fehmarnbelt between the islands of Fehmarn and Lolland is guiding north-westerly winds toward Warnemunde. 

A map that includes areas exposed to ground swells in the Baltic Sea can be found in Brauner et al. (2003). Such areas are in particular the Polish coast in case of northerly winds and the coast and harbors of the Baltic states in case of south westerly to north westerly winds. 

Another possibility to obtain information about the sea state conditions in the southern Baltic Sea is offered by the Atlas zur Ermittlung der Wellenhohe in der siidlichen Ostsee (Schmager, 1979). Figure 7.12 shows the distribution of the wave height for westerly wind with a force of 10 Bft (Table 7.5). 

In mild ice winters, mild southwesterly or westerly winds prevail. Ice forming at sea in the Bay of Bothnia and at times in the Gulf of Finland breaks up and compresses off the Finnish coast, where locally severe ice conditions may occur temporarily. 

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