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21.
WILLIAM B. MEYER 《Geographical review》2004,94(1):43-54
ABSTRACT. Utopian thinkers have often assumed that radical geoengineering is necessary for the creation of a perfect world. This assumption necessarily puts them at odds with environmentalism, but the conflict is not inescapable. Human difficulties with the biophysical world can instead be interpreted as arising from the interaction of environment with society and thus as capable of being eradicated simply by reforming the latter. One notable early exponent of this kind of social constructionism was the American utopian novelist and publicist Edward Bellamy (1850–1898). His fictional and nonfictional writings analyzed the ways in which the troubles that Americans of his time had with weather and climate grew out of their ways of life and political‐economic institutions and would disappear if these were reformed. This line of thought allowed Bellamy to portray a utopia where human beings had ceased to suffer serious harm and inconvenience from the weather yet had not tampered with the atmospheric environment itself. 相似文献
22.
ANDREAS PAUL JOHN J. G. REIJMER JÖRN FÜRSTENAU HANNO KINKEL CHRISTIAN BETZLER 《Sedimentology》2012,59(5):1640-1658
A piston core from the Maldives carbonate platform was investigated for carbonate mineralogy, grain‐size distributions, calcium carbonate content and organic carbon. The sedimentary record was linked to Late Pleistocene sea‐level variations, using an age model based on oxygen isotopes obtained from planktonic foramanifera, nannofossil biostratigraphy and 14C age determinations. The correlation between the sedimentary record and Late Pleistocene sea‐level showed that variations in aragonite and mud during the past 150 000 years were clearly related to flooding and sea floor exposure of the main lagoons of the atolls of the Maldives carbonate platform. Platform flooding events were characterized by strongly increased deposition of aragonite and mud within the Inner Sea of the Maldives. Exposure events, in contrast, can be recognized by rapid decreases in the values of both proxy records. The results show that sediments on the Maldives carbonate platform contain a continuous record of Pleistocene sea‐level variations. These sediments may, therefore, contribute to a better understanding of regional and even global sea‐level changes, and yield new insights into the interplay between ocean currents and carbonate platform morphology. 相似文献
23.
DAVID W. KICKLIGHTER MICHELE BRUNO SILKE DÖNGES GERD ESSER MARTIN HEIMANN JOHN HELFRICH FRANK IFT FORTUNAT JOOS JÖRG KADUK GUNDOLF H. KOHLMAIER A. DAVID McGUIRE JERRY M. MELILLO ROBERT MEYER BERRIEN MOORE III REAS NADLER I. COLIN PRENTICE WALTER SAUF ANNETTE L. SCHLOSS STEPHEN SITCH UWE WITTENBERG GUDRUN WÜRTH 《Tellus. Series B, Chemical and physical meteorology》1999,51(2):343-366
24.
WILLIAM B. MEYER 《Geographical review》2012,102(1):1-16
In an example of what William Freudenburg and his colleagues called the “conjoint construction” of nature and society, hills may represent either assets or liabilities for urban settlement, depending on the period and the activities involved. The relationships between terrain and land use in Syracuse, New York, since the late eighteenth century fall into three major eras. The initial phase, in which settlement largely shunned the lowlands, gave way in the 1820s to one in which canals and railroads stimulated development of the lowlands and in which most land uses, save those of the classic urban fringe, avoided the uplands. A new pattern appeared in the late nineteenth century with the arrival of the electric trolley and the automobile and with provision of a municipal water supply able to reach the city's high ground. Development since then has been consistent with Ernest Burgess's 1929 model of “the poor in the valleys, the well‐to‐do on the hillslopes, and the rich on the hilltops.” 相似文献
25.
Middle Pleistocene to Holocene sediment variations observed in a 26 metre long core taken during a cruise of the RV Marion Dufresne are presented. Core MD992202 was retrieved from the northern slope of Little Bahama Bank and provides an excellent example for sedimentation processes in a mid‐slope depositional environment. The sediment composition indicates sea‐level related deposition processes for the past 375 000 years (marine isotope stages 1 to 11). The sediments consist of: (i) periplatform ooze (fine‐grained particles of shallow‐water and pelagic origin) with moderate variations in carbonate content, carbonate mineralogy and grain‐size; and (ii) coarser intervals with cemented debris consisting of massive, poorly sorted, mud‐supported or clast‐supported deposits with an increased high‐magnesium calcite content. During interglacial stages (marine isotope stages 1, 5, 7, 9 and 11) periplatform oozes (i) are characterized by higher aragonite contents, finer grain‐size and higher organic contents, whereas during glacial stages (marine isotope stages 2 to 4, 6, 8 and 10), increased low‐magnesium and high‐magnesium calcite values, coarser grain‐size and lower organic contents are recorded. These glacial to interglacial differences in mineralogy, grain‐size distribution and organic content clearly show the impact of climatically controlled sea‐level fluctuations on the sedimentation patterns of the northern slope of Little Bahama Bank. The coarser deposits (ii) occur mainly at the transitions from glacial to interglacial and interglacial to glacial stages, and are interpreted as redeposition events, indicating a direct link between sediment properties (changes in mineralogy, grain‐size distribution, variations in organic contents) and sea‐level fluctuations. Changes in hydrostatic pressure and the wave base position during sea‐level changes are proposed to have triggered these large‐scale sediment redepositions. 相似文献
26.
PATRICK J. MULHOLLAND G. RONNIE BEST CHARLES C. COUTANT GEORGE M. HORNBERGER JUDY L. MEYER PETER J. ROBINSON JOHN R. STENBERG R. EUGENE TURNER FRANCISCO VERA-HERRERA ROBERT G. WETZEL 《水文研究》1997,11(8):949-970
The south-eastern United States and Gulf Coast of Mexico is physiographically diverse, although dominated by a broad coastal plain. Much of the region has a humid, warm temperate climate with little seasonality in precipitation but strong seasonality in runoff owing to high rates of summer evapotranspiration. The climate of southern Florida and eastern Mexico is subtropical with a distinct summer wet season and winter dry season. Regional climate models suggest that climate change resulting from a doubling of the pre-industrial levels of atmospheric CO2 may increase annual air temperatures by 3–4°C. Changes in precipitation are highly uncertain, but the most probable scenario shows higher levels over all but the northern, interior portions of the region, with increases primarily occurring in summer and occurring as more intense or clustered storms. Despite the increases in precipitation, runoff is likely to decline over much of the region owing to increases in evapotranspiration exceeding increases in precipitation. Only in Florida and the Gulf Coast areas of the US and Mexico are precipitation increases likely to exceed evapotranspiration increases, producing an increase in runoff. However, increases in storm intensity and clustering are likely to result in more extreme hydrographs, with larger peaks in flow but lower baseflows and longer periods of drought. The ecological effects of climate change on freshwaters of the region include: (1) a general increase in rates of primary production, organic matter decomposition and nutrient cycling as a result of higher temperatures and longer growing seasons: (2) reduction in habitat for cool water species, particularly fish and macroinvertebrates in Appalachian streams; (3) reduction in water quality and in suitable habitat in summer owing to lower baseflows and intensification of the temperature–dissolved oxygen squeeze in many rivers and reservoirs; (4) reduction in organic matter storage and loss of organisms during more intense flushing events in some streams and wetlands; (5) shorter periods of inundation of riparian wetlands and greater drying of wetland soils, particularly in northern and inland areas; (6) expansion of subtropical species northwards, including several non-native nuisance species currently confined to southern Florida; (7) expansion of wetlands in Florida and coastal Mexico, but increase in eutrophication of Florida lakes as a result of greater runoff from urban and agricultural areas; and (8) changes in the flushing rate of estuaries that would alter their salinity regimes, stratification and water quality as well as influence productivity in the Gulf of Mexico. Many of the expected climate change effects will exacerbate current anthropogenic stresses on the region's freshwater systems, including increasing demands for water, increasing waste heat loadings and land use changes that alter the quantity and quality of runoff to streams and reservoirs. Research is needed especially in several critical areas: long-term monitoring of key hydrological, chemical and biological properties (particularly water balances in small, forested catchments and temperature-sensitive species); experimental studies of the effects of warming on organisms and ecosystem processes under realistic conditions (e.g. in situ heating experiments); studies of the effects of natural hydrological variation on biological communities; and assessment of the effects of water management activities on organisms and ecosystem processes, including development and testing of management and restoration strategies designed to counteract changes in climate. © 1997 John Wiley & Sons, Ltd. 相似文献