Seasonal variation, effect

Variability of Seawater Vertical sections through seawater showing the distribution of temperature, salinity, and oxygen for the Pacific Ocean and Western Atlantic Ocean are shown in Figures 21.3 and 21.4. The global variability of natural seawater and its effects on corrosion have been reviewed in particular with respect to seasonal variation of temperature, salinity, oxygen and pH in the Pacific surface water. Data is also given on... 

Atmospheric exposure trials, carried out in Cambridge, established the fact that when rusty specimens were painted in the summer, their condition, after some years exposure, was very much better than that of similar specimens painted in the winter It was found that steel weathered in Cambridge carried spots of ferrous sulphate, deeply imbedded in the rust, and that the quantity of ferrous sulphate/unit area was very much greater in the winter than in the summer this seasonal variation was attributed to the increased sulphur dioxide pollution of the atmosphere in the winter, caused by the combustion of coal in open grates. It was concluded that there was a causal relationship between the quantity of ferrous sulphate and the effective life of the paint. It was suggested that these soluble deposits of ferrous sulphate short-circuit the resistance of the paint film and, since paint films are very permeable to water and oxygen, the ferrous sulphate will become oxidised and hydrolysed with the production of voluminous rust, which will rupture the film at numerous points, thus giving rise to the characteristic type of failure seen on painted rusty surfaces. 

Huhnerfuss, H., B. Pfaffenberger, B. Gehrcke, L. Karbe, W.A. Konig, and O. Landgraf. 1995. Stereochemical effects of PCBs in the marine environment seasonal variation of coplanar and atropisomeric PCBs in blue mussels (Mytilus edulis L.) of the German Bight. Mar. Pollut. Bull. 30 332-340. 

Additionally, vertical fluctuations in the water table due to recovery operations or seasonal variation in precipitation have a direct effect upon the apparent or measured LNAPL thickness (Figure 6.6d). As the water table elevation declines gradually due to seasonal variations, for example, an exaggerated apparent thickness occurs, reflecting the additional hydrocarbon that accumulated in the monitoring well. The same is true for an area undergoing recovery operations where the... 

In addition, seasonal variations may also influence the levels of APIs found. A seasonal influence on the FQs and TCs detection frequency in Coimbra (Portugal) municipal and hospital wastewaters was reported [34, 55]. Seasonal variations of up to a factor of four were also reported in a Finnish river [99, 100]. Seasonal variations can also affect the efficiency of WWTPs and river discharges since in winter the microbial activity is reduced due to low temperatures and the dilution effect is higher. Ultimately, at a wider level, geographical situation and climate may also explain different contamination scenarios between countries in different climatic zones [99, 100]. 

Rotchell, J.M., Clarke, K.R., Newton, L.C., Bird, D.J. (2001). Hepatic metallothionein as a biomarker for metal contamination age effects and seasonal variation in European flounders (Pleuronectes flesus) from the Severn estuary and Bristol Channel. Marine Environmental Research, 52 151-171. 

A similar relationship was observed in Germany. Figure 12.36, for example, shows the deviation of the monthly mean ozone concentration after corrections for seasonal variations, long-term trends, the QBO and vortex effects, and the associated particle surface area concentration from 1991 to 1994 (Ansmann et al., 1996). The increase in the particle surface area due to Mount Pinatubo is clear associated with this increase in aerosol particles are negative monthly mean deviations in ozone that persist until fall 1993, when the surface area approaches the preeruption values. Similarly, the decrease in the total column ozone from 1980-1982 to 1993 observed at Edmonton, Alberta, Canada, and shown at the beginning of this chapter in Fig. 12.1 has been attributed to the effects of the Mount Pinatubo eruption (Kerr et al., 1993). 

Figure 4. Ground level air concentration of radionuclides whose concentration has been effected by seasonal variations and recent nuclear weapons testing...

The effect of aircraft emissions on radiative forcing is summarized in Table 5. The global and annual radiative forcing due to subsonic aviation is calculated to be 0.036 Wm 2, which is larger than the value of 0.029 Wm 2 calculated in Section 2.1 (0.121-0.092 from Table 2), mainly due to the inclusion of water vapor emission here. The combined fleet provides a radiative forcing 0.055 Wm 2. Note that the water vapor emission from supersonic aviation plays an important role, providing 0.031 (=0.05-0.019) and 0.027 (=0.059-0.032) Wm-2 respectively in January and July. The results also show strong latitudinal and seasonal variations. 

These compositional considerations necessitate attention to raw materials evaluation early in process research and development to (1) establish an in-depth knowledge of the principal raw material, including its composition and history of materials handling prior to arrival at the factory, (2) investigate the effects of seasonal variations and storage under various conditions on composition and on hydrolytic performance, and (3) explore alternative pretreatment processes for upgrading the composition and hydrolytic performance of available raw materials. The resource that is for sale is not pure cellulose it is a complex mixture containing cellulose caveat emptor. 

Seasonal variations of temperature Effects on vegetation distribution and lapse rates... 

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