Secular trend

The condensed phases also are important to the physical processes of the atmosphere however, their role in climate poses an almost entirely open set of scientific questions. The highest sensitivity of physical processes to atmospheric composition lies within the process of cloud nucleation. In turn, the albedo (or reflectivity for solar light) of clouds is sensitive to the number population and properties of CCN (Twomey, 1977). At this time, it appears impossible to predict how much the temperature of the Earth might be expected to increase (or decrease in some places) due to known changes in the concentrations of gases because aerosol and cloud effects cannot yet be predicted. In addition, since secular trends in the appropriate aerosol properties are not monitored very extensively there is no way to know... 

If required by the model(s) to be used, back-up data for each entry in the matrix or table may be supplied to resolve the total mass flow into spatial cells (UTM coordinates, depth or height), temporal cells (hourly frequency distributions, diurnal cycles, seasonal subdivisions or secular trends on annual intervals) or speciation cells (by valency state of anions or by hydrocarbon structure, for example). The level of difficulty encountered by the user in supplying these data may influence the choice of model(s). 

These "effects", in fact. Include sporadic manifestations, susceptible to secular trends in that the longer the tenure, the more likely the sporadic effect may be experienced. 

Veizer J, Hoefs J (1976) The nature of and C/ C secular trends in sedimentary carbon-... 

However, differences between the care provided to patients in the trial and that provided to patients in this group may be due as much to secular trends in the provision of medical care as they are to the adoption of a study protocol. For example, length of stay in the United States has decreased since the early 1980s, due in part to the implementation of the Medicare Prospective Payment System. Thus, historical cohorts from earlier periods may have had longer lengths of stay as inpatients than is currently seen in clinical practice. These data may suggest a protocol-induced decrease in length of stay when one actually does not exist. 

Briefel, R.R. and Johnson, C.L. 2004. Secular trends in dietary intake in the United States. Anrm. Rev. Nutr. 24, 401 431. 

The most important (and controversial) conclusion by Jacobson (2002a, b) concerning the anthropogenic nature of present-day climate change is based on analysis of the SAT and SST combined data (i.e., on the secular trend of mean average annual global surface temperature, GST). In this connection, two questions arise ... 

Figure 10.6. Observed secular trends in the chemical composition of sedimentary rocks. Eu/Eu = ratio of observed normalized Eu concentration to that predicted (Eu ) from extrapolation between REE Gd and Sm. REE = rare earth element LREE = light REE HREE = heavy REE. Data from several authors as presented in Veizer (1988).

Veizer J. and Hoefs J. (1976) The nature of 180/160 and 13C/12C secular trends in sedimentary carbonate rocks. Geochim. Cosmochim. Acta 40, 1387-1395. 

Kono, S. Secular trend of colon cancer incidence and mortality in relation to fat and meat intake in Japan. Eur. J. Cancer. Prev. 13(2), 127-132, 2004. 

Race and sex differences in the distribution of cerebral atherosclerosis. Stroke 27 1974-1980 Wolf PA, D Agostino RB, O Neal MA et al. (1992). Secular trends in stroke incidence and mortality the Framingham Study. Stroke 23 1551-1555... 

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