Climate formation

Estimates of RF obtained with due regard to GHGs and aerosol are of importance in giving substance to conclusions concerning the contribution of anthropogenic factors to climate formation. The correctness of these conclusions is restricted, however, by three factors. One is that the interactivity of these factors... 

Information on the content of carbon dioxide and methane in air bubbles contained in ice kerns reflects the important role of these minor gas constituents (MGCs) in climate formation, but it is still unclear what took place first change in temperature or in MGC content. For instance, it was recently shown that during four interglacial periods, changes in temperature in the Antarctic took place about 4,000 years before the changes in C02 concentration. 

Crowley (2000) estimated the contributions of various factors to climate formation (SAT changes) for the last 1,000 years using an energy-balance model of climate. According to the results obtained... 

The main difficulty in understanding the causes of climate change is connected with the impossibility of considering climatic feedbacks sufficiently reliably. Primarily, this refers to cloud-radiation feedback, direct and indirect (by the effect on radiation properties of clouds) impacts of atmospheric aerosols on climate, and the impact of the atmosphere-ocean interaction on climate formation. 

The Phocene lignites in Alaska, southeastern Europe, and southern Nigeria are the youngest coals. A number of peat accumulations in different parts of the world representing a range of climates indicate that the process of coal formation continues to take place. 

Minerals of sodium sulfate occur naturally throughout the world. The deposits result from evaporation of inland seas and terminal lakes. Colder climates, such as those found ia Canada and the former Soviet Union, favor formation of mirabilite. Warmer climates, such as those found ia South America, India, Mexico, and the western United States, favor formation of thenardite. In areas where other anions and cations are present, double salts can be found of the kiads shown ia Table 2, which Hsts nearly all naturally occurring minerals containing sodium sulfate. Except for mirabilite, thenardite, and astrakanite, these mineral deposits play a minor role ia sodium sulfate production. 

Numerous analyses of data routinely collected in the United States have been performed by the U.S. National Climatic Center, results of these analyses are available at reasonable cost. The joint frequency of Pasquill stability class, wind direction class (primarily to 16 compass points), and wind speed class (in six classes) has been determined for various periods of record for over 200 observation stations in the United States from either hourly or 3-hourly data. A computer program called STAR (STability ARray) estimates the Pasquill class from the elevation of the sun (approximated from the hour and time of year), wind speed, cloud cover, and ceiling height. STAR output for seasons and the entire period of record can be obtained from the Center. Table 21-2 is similar in format to the standard output. This table gives the frequencies for D stability, based on a total of 100 for all stabilities. 

One such feedback is the influence of clouds and water vapor. As the climate warms, more water vapor enters the atmosphere. But how much And which parts of the atmosphere, high or low And how does the increased humidity affect cloud formation While the relationships among clouds, water vapor, and global climate are complicated in and of themselves, the situation is further complicated by the fact that aerosols exert a poorly understood influence on clouds. 

The last published report of the IPCC acknowledges that the single largest uncertainty in determining the climate sensitivity to either natural or anthropogenic changes are clouds and their effects on radiation and their role in the hydrological cycle. .. At the present time, weaknesses in the parameterization of cloud formation and dissipation are probably the main impediment to improvements in the simulation of cloud effects on climate (IPCC, 1995, p. 346). 

The value of E is insensitive to small changes in ocean temperature but is quite sensitive to wind speed over the sea surface (boundary layer thickness, wave action, and bubble formation are functions of wind speed). Therefore changes in surface wind speed accompanying a climate change could affect rates of air-sea CO2 exchange. 

Although it is one of the smallest reservoirs in terms of water storage, the atmosphere is probably the second most important reservoir in the hydrosphere (after the oceans). The atmosphere has direct connections with all other reservoirs and the largest overall volume of fluxes. Water is present in the atmosphere in solid, liquid, and vapor forms, all of which are important components of the Earth s natural greenhouse effect. Cycling of water within the atmosphere, both physically (e.g. cloud formation) and chemically, is also integral to other biogeochemical cycles and climate. Consult Chapter 17 for more details. 

Many important erosion-related phenomena are episodic and infrequent, such as flash floods, landslides, and glaciations, while others such as orogenesis and soil formation involve time scales that exceed those of major climate fluctuations. In either case, the time scale of human existence is too short to make adequate observations. Consequently, it is difficult to directly estimate the rates or characterize the effects of such phenomena on erosion products. The key to understanding weathering and erosion, on a continental scale, is to decipher the relationship between landforms, the processes that produce them, and the chemistry and discharge of river-borne materials. 

Tardy, Y., Bocquier, G., Paquet, H., and Millot, G. (1973). Formation of clay from granite and its distribution in relation to climate and topography. Geoderma 10, 271-284. 

The conveyor belt is shown schematically in Fig. 10-11. Warm and salty surface currents in the western North Atlantic (e.g., the Gulf Stream) transport heat to the Norwegian-Greenland Seas where it is transferred to the atmosphere. This heat helps moderate the climate of northern Europe. The cooling increases the density resulting in formation of the now cold and salty North Atlantic Deep Water (NADW) (Worthington, 1970). The NADW travels south through the North and South Atlantic and then joins the Circumpolar Current that travels virtually unimpeded in a clockwise direction around the Antarctic Continent. 

Atmospheric aerosols have a direct impact on earth s radiation balance, fog formation and cloud physics, and visibility degradation as well as human health effect[l]. Both natural and anthropogenic sources contribute to the formation of ambient aerosol, which are composed mostly of sulfates, nitrates and ammoniums in either pure or mixed forms[2]. These inorganic salt aerosols are hygroscopic by nature and exhibit the properties of deliquescence and efflorescence in humid air. That is, relative humidity(RH) history and chemical composition determine whether atmospheric aerosols are liquid or solid. Aerosol physical state affects climate and environmental phenomena such as radiative transfer, visibility, and heterogeneous chemistry. Here we present a mathematical model that considers the relative humidity history and chemical composition dependence of deliquescence and efflorescence for describing the dynamic and transport behavior of ambient aerosols[3]. 

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