Climate variations

Global warming would also be expected to influence surface waters such as lakes and streams, through changes induced in the hydrologic cycle. However, the last published report of the IPCC states no clear evidence of widespread change in annual streamflows and peak discharges of rivers in the world (IPCC, 1995, p. 158). Wliile lake and inland sea levels have fluctuated, the IPCC also points out that local effects make it difficult to use lake levels to monitor climate variations. 

Aber, J. D. and Driscoll, C. T. (1997). Effects of land use, climate variation, and N deposition on N cycling and C storage in northern hardwood forests, Global Biogeochem. Cycles 11, 639-648. 

Fig. 18-8 Characteristic temperature-depth distributions at an ice divide. For a climatic temperature history as shown in (a) the temperature-depth distribution changes as shown in (b). Following the step increase in surface temperature, the initial steady temperature profile (fi in (b)) is altered by a warming wave (e.g., at time fa) but eventually reaches a new steady profile by time t. (c) Temperature data from Greenland measured by Gary Clow of the US Geological Survey, showing wiggles due to climate variations (Cuffey et ah, 1995).

Van Klinken, GJ, Van der Plicht, J. and Hedges, RE.M. 1994 Bone C/ C ratios reflect (palaeo) climatic variations. Geophysical Research Letters 21 445-448. 

Stuart-Williams, H.L.Q. and Schwarcz, HP. 1997 Oxygen isotopic determination of climatic variation using phosphate from beaver bone, tooth enamel, and dentine. Geochimica et Cosmochimica Acta (iV. 2539-2550. 

The soil and plants employed on the cover are critical to success. A mixture of grasses native to the area is preferred to provide effective water removal from the cover in all years in spite of temporary changes in local conditions. Native grasses have already proven their ability to withstand local climate variations, insects, plant disease, periodic fire, and other factors. A mixture of native grasses assures an active vegetative cover during years when insects, plant disease, or other factors reduce the vigor of one or more species.11-38... 

The extensive layered sediments at the south pole, which contain water ice, will provide information on climatic variations. The subsurface sounding radar instrument SHARAD (Shallow Radar) on board the Mars Reconnaissance Orbiter carried out a detailed cartographic study of the subsurface at the Martian south pole. The data indicate that the sediments there have been subjected to considerable erosion (R. Seu et al 2007). The density of the material deposited at the Martian south pole was calculated by M. T. Zuber and co-workers by combining data from the gravitational field with those from various instruments on board the Mars Orbiter, they obtained a value of 1,200 kg/m3. This value corresponds to that calculated for water ice containing about 15% dust (Zuber et al 2007). 

Thompson, P., Schwarcz, H. P., Ford, D. C., Continental Pleistocene climatic variations from speleothem age and isotopic data, Science, 184, 893-895 (1974). 

For more than 80 years, tree-ring data have been used to make inferences about past climatic variation. In general, the characteristic most often used has been the variations in widths of the annual growth rings. However, during the past decade other properties, such as cell density (measured by x-ray densiometric techniques), relative widths of early and late wood, and isotopic composition of the cellulose have been used to infer past environmental conditions. It is the isotopic composition that is of interest here. 

We conclude from the correlations of these four sets of data that the calculation of Dansgaard et al., [41] of the age of ice versus depth in the Greenland ice cap seems to be correct with an error of not more than a couple of years, at least over the last 800 years. We conclude that the climate variations in Greenland, southern Japan, and southern California have had the same periodicities for the last 800 years or more. 

If the stable isotope ratio of 13C/12C is to be further measured in tree rings and interpreted as an indicator of climate variation, (and we have barely begun to initiate its use as a thermometer in the present work, confining our measurements to the stable isotopes in water, because water is so abundant compared to carbon dioxide and because the dependence of its isotope ratios is relatively simple compared with those of carbon dioxide), some more sophisticated considerations must be given to the distribution of carbon dioxide among the reservoirs on the surface of the earth. 

Predicting climate variations over a human lifetime. 

There are also annual climatic differences which affect host and pest. An organic control measure that works well one year may not work well the following year because of this climatic variation. 

In the last decades, several ice cores over 1,000 m depth have been recovered from Greenland and Antarctica. In these cores, seasonal variations are generally observed only for the uppermost portions. After a certain depth, which depends on accumulation rates, seasonal variations disappear completely and isotopic changes reflect long-term climatic variations. No matter how thin a sample one cuts from the ice core, its isotope composition will represent a mean value of several years of snow deposition. 

Although Fourier s "greenhouse analogy is not strictly correct, it provides a simple explanation of how the atmosphere traps heat that is still generally accepted. Fourier placed relatively little emphasis on the "greenhouse effect in long-term climatic variations, however, as he believed that astronomical factors were far more important in determining these effects. For example, he made no effort to explain the chemical process hy which heat is retained in the atmosphere. 

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