在全球增温的背景下,延安市局地温度也在随之发生变化。从2012年开始延安市通过“削山造城”的方式将在10年时间内整理出78.5 km 2的土地,这样大范围土地利用方式的改变,必将通过陆气作用也对局地气候产生影响,所以有必要对延安市近年...在全球增温的背景下,延安市局地温度也在随之发生变化。从2012年开始延安市通过“削山造城”的方式将在10年时间内整理出78.5 km 2的土地,这样大范围土地利用方式的改变,必将通过陆气作用也对局地气候产生影响,所以有必要对延安市近年来的温度变化特征进行客观分析。本研究分析了延安市近50年来气温变化特征及其影响因素,得出以下结论:(1)1973~2012年期间,延安市年均温度距平与全球年均温度距平和北半球年均温度变化趋势一致,说明在此阶段延安地区温度主要受全球变暖趋势的影响;(2)2013~2018年延安市年均温度变化趋势与全球年均温度和北半球年均温度、兰州、银川、太原等其他同纬度城市变化趋势相反,可能是由于2012年以来的“削山造城”工程导致风速增大造成的。展开更多
The distributions of strata rock temperature around a driving head with auxil- iary ventilation were analyzed theoretically based on a program which was developed by the authors to predict the thermal environmental co...The distributions of strata rock temperature around a driving head with auxil- iary ventilation were analyzed theoretically based on a program which was developed by the authors to predict the thermal environmental conditions in a development heading with forcing auxiliary ventilation. The influences of wetness of the airway surface were dis- cussed on the cooled zone of the strata rock and on the temperature distribution in the surrounding rock. It is shown that the advancing speed and driving time have little influ- ence on the temperature profile in front of the working face of a driving airway, and the rock temperature 1.5 m ahead of the working face can be taken as the virgin rock tem- perature.展开更多
Understanding the regional hydrological response to varying CO_(2)concentration is critical for cost-benefit analysis of mitigation and adaptation polices in the near future. To characterize summer monsoon rainfall ch...Understanding the regional hydrological response to varying CO_(2)concentration is critical for cost-benefit analysis of mitigation and adaptation polices in the near future. To characterize summer monsoon rainfall change in East Asia in a changing CO_(2)pathway, we used the Community Earth System Model(CESM) with28 ensemble members in which the CO_(2)concentration increases at a rate of 1% per year until its quadrupling peak, i.e., 1468 ppm(ramp-up period), followed by a decrease of 1% per year until the present-day climate conditions, i.e., 367 ppm(ramp-down period). Although the CO_(2)concentration change is symmetric in time, the amount of summer rainfall anomaly in East Asia is increased 42% during a rampdown period than that during a ramp-up period when the two periods of the same CO_(2)concentration are compared. This asymmetrical rainfall response is mainly due to an enhanced El Ni?o-like warming pattern as well as its associated increase in the sea surface temperature in the western North Pacific during a ramp-down period. These sea surface temperature patterns enhance the atmospheric teleconnections and the local meridional circulations around East Asia, resulting in more rainfall over East Asia during a ramp-down period. This result implies that the removal of CO_(2)does not guarantee the return of regional rainfall to the previous climate state with the same CO_(2)concentration.展开更多
文摘在全球增温的背景下,延安市局地温度也在随之发生变化。从2012年开始延安市通过“削山造城”的方式将在10年时间内整理出78.5 km 2的土地,这样大范围土地利用方式的改变,必将通过陆气作用也对局地气候产生影响,所以有必要对延安市近年来的温度变化特征进行客观分析。本研究分析了延安市近50年来气温变化特征及其影响因素,得出以下结论:(1)1973~2012年期间,延安市年均温度距平与全球年均温度距平和北半球年均温度变化趋势一致,说明在此阶段延安地区温度主要受全球变暖趋势的影响;(2)2013~2018年延安市年均温度变化趋势与全球年均温度和北半球年均温度、兰州、银川、太原等其他同纬度城市变化趋势相反,可能是由于2012年以来的“削山造城”工程导致风速增大造成的。
基金Supported by Natural Science Foundation of Henan Province (0311051900)Supported by Fundamental Research Project of Education De-partment of Henan Province (2003440221)
文摘The distributions of strata rock temperature around a driving head with auxil- iary ventilation were analyzed theoretically based on a program which was developed by the authors to predict the thermal environmental conditions in a development heading with forcing auxiliary ventilation. The influences of wetness of the airway surface were dis- cussed on the cooled zone of the strata rock and on the temperature distribution in the surrounding rock. It is shown that the advancing speed and driving time have little influ- ence on the temperature profile in front of the working face of a driving airway, and the rock temperature 1.5 m ahead of the working face can be taken as the virgin rock tem- perature.
基金supported by the National Research Foundation of Korea(NRF) grant(NRF-2018R1A5A1024958)。
文摘Understanding the regional hydrological response to varying CO_(2)concentration is critical for cost-benefit analysis of mitigation and adaptation polices in the near future. To characterize summer monsoon rainfall change in East Asia in a changing CO_(2)pathway, we used the Community Earth System Model(CESM) with28 ensemble members in which the CO_(2)concentration increases at a rate of 1% per year until its quadrupling peak, i.e., 1468 ppm(ramp-up period), followed by a decrease of 1% per year until the present-day climate conditions, i.e., 367 ppm(ramp-down period). Although the CO_(2)concentration change is symmetric in time, the amount of summer rainfall anomaly in East Asia is increased 42% during a rampdown period than that during a ramp-up period when the two periods of the same CO_(2)concentration are compared. This asymmetrical rainfall response is mainly due to an enhanced El Ni?o-like warming pattern as well as its associated increase in the sea surface temperature in the western North Pacific during a ramp-down period. These sea surface temperature patterns enhance the atmospheric teleconnections and the local meridional circulations around East Asia, resulting in more rainfall over East Asia during a ramp-down period. This result implies that the removal of CO_(2)does not guarantee the return of regional rainfall to the previous climate state with the same CO_(2)concentration.
