Man-Made Climatic Changes

Abstract

Natural climatic fluctuations, even those of recent years, cover a considerable range. They can be characterized as a "noise" spectrum which masks possible global effects of man-caused increases of atmospheric CO(2) and particulates. Local modifications, either deliberate or inadvertent, measurably affect the microclimate. Some artificial alterations of the microlimate are beneficial in agriculture. Among the unplanned effects, those produced by urbanization on local temperature and on wind field are quite pronounced. The influences on rainfall are still somewhat controversial, but effects may extend considerably beyond the confines of metropolitan areas. They are the result of water vapor released by human activity and of the influence of condensation and freezing nuclei produced in overabundance by motor vehicles and other combustion processes. Therefore it appears that on the local scale man-made influences on climate are substantial but that on the global scale natural forces still prevail. Obviously this should not lead to complacency. The potential for anthropogenic changes of climate on a larger and even a global scale is real. At this stage activation of an adequate worldwide monitoring system to permit early assessment of these changes is urgent. This statement applies particularly to the surveillance of atmospheric composition and radiation balance at sites remote from concentrations of population, which is now entirely inadequate. In my opinion, man-made aerosols, because of their optical properties and possible influences on cloud and precipitation processes, constitute a more acute problem than CO(2). Many of their effects are promptly reversible; hence, one should strive for elimination at the source. Over longer intervals, energy added to the atmosphere by heat rejection and CO(2) absorption remain matters of concern.

Seasonal and Diurnal Characteristics of Land Surface Temperature and Major Explanatory Factors in Harris County, Texas

“…Comparing daytime and nighttime LST shows that the diurnal temperature range is reduced in the central urban and high-intensity building areas, while croplands/natural vegetation areas with less human activity experience a greater diurnal temperature range which also has been documented in other studies [13,45]. Water bodies and wetlands have the lowest daily temperature range because water allows light to penetrate into deep layers without sensible heat transfer during the day resulting in cooler surface temperatures, while at night water bodies lose heat less slowly compared to land to form a hotter surface.…”

Heat Stroke

“…Air conditioners are considered one of the most important protective factors for sedentary, elderly individuals, and the very young whereas fan cooling is an ineffective strategy (92,262). Metropolitan cities experience higher temperatures than surrounding urban areas due to reduced vegetation and large areas of pavement ("urban heat islands"), which affects the manner in which water and heat are exchanged between the land and atmosphere (204).…”

Large-scale urbanization effects on eastern Asian summer monsoon circulation and climate

“…As an extreme case of LUCC, urbanization can significantly affect the weather and climate on both local and regional scales (Landsberg 1970;Changnon 1992;Kalnay and Cai 2003;Shepherd 2005;Lamptey et al 2005;Lim et al 2005;Kaufmann et al 2007;Trusilova et al 2008Trusilova et al , 2009Oleson et al 2010). During the past decades, urbanization and its climate impacts Abstract Impacts of large-scale urbanization over eastern China on East Asian summer monsoon circulation and climate are investigated by comparing three 25-year climate simulations with and without incorporating modified land cover maps reflecting two different idealized large-scale urbanization scenarios.…”