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A generalized,structural,time series modeling framework was developed to analyze the monthly records of absolute surface temperature,one of the most important environmental parameters,using a deterministicstochastic combined(DSC) approach.Although the development of the framework was based on the characterization of the variation patterns of a global dataset,the methodology could be applied to any monthly absolute temperature record.Deterministic processes were used to characterize the variation patterns of the global trend and the cyclic oscillations of the temperature signal,involving polynomial functions and the Fourier method,respectively,while stochastic processes were employed to account for any remaining patterns in the temperature signal,involving seasonal autoregressive integrated moving average(SARIMA) models.A prediction of the monthly global surface temperature during the second decade of the 21st century using the DSC model shows that the global temperature will likely continue to rise at twice the average rate of the past 150 years.The evaluation of prediction accuracy shows that DSC models perform systematically well against selected models of other authors,suggesting that DSC models,when coupled with other ecoenvironmental models,can be used as a supplemental tool for short-term(~10-year) environmental planning and decision making. 相似文献
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Susan H. Cannon Eric M. Boldt Jayme L. Laber Jason W. Kean Dennis M. Staley 《Natural Hazards》2011,59(1):209-236
Following wildfires, emergency-response and public-safety agencies can be faced with evacuation and resource-deployment decisions
well in advance of coming winter storms and during storms themselves. Information critical to these decisions is provided
for recently burned areas in the San Gabriel Mountains of southern California. A compilation of information on the hydrologic
response to winter storms from recently burned areas in southern California steeplands is used to develop a system for classifying
magnitudes of hydrologic response. The four-class system describes combinations of reported volumes of individual debris flows,
consequences of debris flows and floods in an urban setting, and spatial extents of the hydrologic response. The range of
rainfall conditions associated with different magnitude classes is defined by integrating local rainfall data with the response
magnitude information. Magnitude I events can be expected when within-storm rainfall accumulations (A) of given durations (D) fall above the threshold A = 0.4D
0.5 and below A = 0.5D
0.6 for durations greater than 1 h. Magnitude II events will be generated in response to rainfall accumulations and durations
between A = 0.4D
0.5 and A = 0.9D
0.5 for durations less than 1 h, and between A = 0.5D
0.6 and A = 0.9D
0.5 or durations greater than 1 h. Magnitude III events can be expected in response to rainfall conditions above the threshold
A = 0.9D
0.5. Rainfall threshold-magnitude relations are linked with potential emergency-response actions as an emergency-response decision
chart, which leads a user through steps to determine potential event magnitudes and identify possible evacuation and resource-deployment
levels. Use of this information in planning and response decision-making process could result in increased safety for both
the public and emergency responders. 相似文献
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Abstract: This article explores environmental imaginaries of colonization in lowland Canterbury. In 1844 Edward Shortland observed that his Māori companions had an exceptionally detailed geographical knowledge of the area and its resources, yet a few years later European settlers were viewing it as an empty stage on which to envision newly‐constructed landscapes. The terrain was contested, but colonial ‘improvement’, through the creation of spaces of modernity, took no cognizance of this. The legacies of that transformation are a simplified, orderly landscape, and fractured but persistent memories of indigenous ecosystems that are now being revived. 相似文献
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Charles P. Gerba Sagar M. Goyal Eric M. Smith Joseph L. Melnick 《Marine pollution bulletin》1977,8(12):279-282
Significant concentrations of human enteric viruses and bacteria were found to be present in the water and sediment of a coastal canal community into which secondarily treated sewage was being discharged. 相似文献