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91.
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Low level cloud motion vectors from Kalpana-1 visible images 总被引:1,自引:0,他引:1
INDERPREET KAUR S K DEB C M KISHTAWAL P K PAL RAJ KUMAR 《Journal of Earth System Science》2013,122(4):935-946
93.
M. PAUL MOSLEY 《水文科学杂志》2013,58(2):249-267
Abstract The response of monthly 7-day low flow, monthly instantaneous peak flow, and monthly frequency of flood events to El Niño and La Niña episodes is investigated for 18 rivers that represent a diverse range of climatic types throughout New Zealand. A significant positive or negative deviation from the long-term average was observed in over half the possible combinations of river, streamflow index, and type of ENSO episode; significant deviations were most frequent in the case of low flow, especially during La Niña episodes. Patterns of streamflow response differ widely between rivers, and the response of a given river to individual ENSO episodes is very variable. The patterns of streamflow response to ENSO are consistent to some extent with the climatic effects of ENSO already identified by meteorologists. Two core regions can be defined in which streamflow tends to respond in the same way. These are in the northeast of the North Island, and in the axial ranges of the South Island, where there are significant effects of ENSO on the frequency and duration of rain-bearing northeasterly and westerly winds respectively. The patterns of response strongly reflect topography, and the exposure of catchments to predominant air masses. 相似文献
94.
Abstract Daily flow records, rainfall data and tropical cyclone maps during 1970–1998 are used to document the impact of tropical cyclones (TCs) on floods in the Rewa River system, Viti Levu, Fiji. Floods are large, brief, isolated events caused by TCs and non-TC tropical rainstorms. More floods are caused by tropical rainstorms than by TCs, but TC floods are larger. The log Pearson Type III distribution consistently provided the best fit to partial duration flood series and the widely-recommended generalized Pareto distribution performed very poorly, underscoring the need to test a variety of distributions for a particular geographic location. Tropical cyclones occur more often in Fiji during negative values of the Southern Oscillation Index (SOI) and all TCs that occurred during El Niño conditions caused floods. Peak flood discharges caused by TCs are inversely correlated with the SOI, reflecting possible links with tropical cyclone frequency and precipitation intensity. 相似文献
95.
JONATHAN KÖHLER TERRY BARKER HAORAN PAN PAOLO AGNOLUCCI PAUL EKINS TIM FOXON 《Climate Policy》2013,13(2):156-161
The direction of UK energy policy requires a renewed impetus if the goal of climate change stabilization is to be met. Cost is not the main issue: a transformation to a low-carbon energy system may be no more expensive than meeting future energy demands with fossil fuels. Institutional barriers are preventing the large-scale adoption of the necessary technologies. New institutions to promote low-carbon technologies have not yet led to investment on the necessary scale. Further changes to the operation of the UK electricity markets to create a ‘level playing field’ for small-scale and intermittent generation are necessary. UK policy can contribute to international agreements following on from the Kyoto Accord, which also need to address the institutional barriers to energy technology development and transfer. 相似文献
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B AJAYKUMAR K SREEDHARAN MAHESH MOHAN JOBY PAUL A P THOMAS P K K NAIR 《Journal of Earth System Science》2012,121(4):1093-1103
The climatic variability and the influence of temperature and sea level fluctuations on the earth??s surface configuration during the Holocene are being discussed all over the world. The present study evaluates the palaeo-environmental conditions of western coast of India during this epoch through the analysis of pollen grains embedded in a carbonaceous clay formation (? 0.4?C0.6?m) found sandwiched within the palaeodeposit of sand of Meenachil River basin. The carbon dating revealed that the clay formation has an age of 5786 ± 94 14C yr BP, while the embedded wood samples have the age varying in between 2888 ± 78 and 5780 ± 95 14C yr BP. The overall analysis suggests that the southwestern margin of India had experienced high intensity rainfall during the earlier part of the Atlantic chronozone due to then strengthened Asiatic monsoon, while water stagnation and hydrological modifications were observed during the later part. The dominance of weeds and lesser number of tree elements suggested a drier climate during the end of the Atlantic period. Besides, the morphometric rearrangement of the Meenachil River contemporaneous to the geomorphological modifications of the southwestern coast of India shall be classified into three categories: (1) Pre-Vembanad Lake formation, (2) Contemporaneous to lake formation and (3) Post-Lake formation. 相似文献
98.
ABSTRACT. Environmental narratives in Africa have been examined in a flurry of publications since the mid‐1990s. In this article we seek to offer insights into the role and motivations of volunteer development workers in perpetuating environmental narratives. We examine the factors that led to the questioning or nonquestioning of environment‐development discourses and their influence, if any, on the actual work undertaken by volunteers. As former development volunteers, we also explore the role that the development‐volunteer experience subsequently played in shaping our own research as academics. Our analysis is based largely on our tenure as U.S. Peace Corps volunteers in Mali from 1987 until 1989 and our later experiences as academics. We draw on our memories, interviews with former colleagues, and training materials to describe how volunteers were introduced to, and encouraged to act on, environmental problems in the West African Sudano‐Sahel. We adopt a reflexive approach to explore briefly how our experiences as volunteers influenced our research and writing as academics. 相似文献
99.
ABSTRACT. Twentieth‐century land reform in Chile reflects familiar themes. The state subdivided large land monopolies, ostensibly for social justice reasons: to provide opportunities for campesinos to earn a living from agriculture. In southern Chile's Tierra del Fuego a combination of social justice, nationalism, and geopolitical concerns stimulated land reform between 1924 and 1978. The effort succeeded in creating a new material landscape oriented around smaller ranches but failed to meet its socioeconomic goals. In a scenario that resonates with reforms elsewhere in Latin America, an elitist cultural landscape dominated by large‐holding corporations was replaced with another elitist landscape, though in a different form. Politically well‐connected and essentially absentee landholders acquired subdivided land and began to practice “hobby ranching.” The history of land reform in Tierra del Fuego demonstrates how new socioeconomic conditions created over the course of many decades have left their imprint on land use and the biophysical landscape. It also contributes to larger regional debates about the role of land degradation in stocking‐rate decline. 相似文献
100.