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981.
研究过去有关广西气候区划的成果和1961~2000年气候整编资料,以稳定通过10℃期间的积温6900℃和8000℃等积温线作为划分气候带的指标,以2~4月降水量300mm,200mm等雨量线和1月平均气温9℃等温线作为划分气候区的指标,制作新的广西气候区划,并评述各气候区的气候特点。广西气候划分为3个气候带,9个气候区。3个气候带自北向南分为中亚热带、南亚热带和北热带,各气候区命名为:中亚热带东北部气候区、中亚热带北部气候区、中亚热带东南部气候区、中亚热带桂中气候区、中亚热带西南部气候区、南亚热带东部气候区、南亚热带中部气候区、南亚热带西部气候区、沿海北热带气候区。 相似文献
982.
田睿 《重庆工商大学学报(自然科学版)》2017,34(1):80-86
为了研究气候变化对沿海重工业供应系统的影响,介绍了重工业为何分布在沿海地区、气候变化的现状、可持续供应链及可持续供应链管理的定义和发展;指出了气候变化对重工企业可持续供应链的影响;阐释了为对抗气候变化而形成的监管制度,研究了重工业对监管环境变化的适应性及其承担的风险;论述了企业面对气候变化所作的回应,以及对抗气候变化的必要性和对抗战略的可行性。 相似文献
983.
基于气候资源利用的长子大青椒种植气象条件分析 总被引:1,自引:0,他引:1
选用长子县1981—2010年30年气象资料,通过日光大棚小气候调查,分析适宜大青椒大棚生长的气象条件,进而探讨了工厂化育苗及大田种植的技术问题,以实现大青椒早栽上市或延迟种植错峰上市的目的。 相似文献
984.
ZHOU XiuJi ZHAO Ping LIU Ge & ZHOU TianJun State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing China National Meteorological Information Centre The State Key Laboratory of Numerical Modeling for Atmospheric Sciences Geophysical Fluid Dynamics 《科学通报(英文版)》2011,(Z2):3003-3011
Using meteorological observations, proxies of precipitation and temperature, and climate simulation outputs, we synthetically analyzed the regularities of decadal-centennial-scale changes in the summer thermal contrast between land and ocean and summer precipitation over the East Asian monsoon region during the past millennium; compared the basic characteristics of the East Asian summer monsoon (EASM) circulation and precipitation in the present day, the Little Ice Age (LIA) and the Medieval Warm Period (MWP); and explored their links with solar irradiance and global climate change. The results indicate that over the last 150 years, the EASM circulation and precipitation, indicated by the temperature contrast between the East Asian mainland and adjacent oceans, had a significant decadal perturbation and have been weaker during the period of rapid global warming over the past 50 years. On the centennial time scale, the EASM in the MWP was strongest over the past 1000 years. Over the past 1000 years, the EASM was weakest in 1450-1570. When the EASM circulation was weaker, the monsoon rain belt over eastern China was generally located more southward, with there being less precipitation in North China and more precipitation in the Yangtze River valley; therefore, there was an anomalous pattern of southern flood/northern drought. From the 1900s to 1920s, precipitation had a pat- tern opposite to that of the southern flood/northern drought, with there being less precipitation in the Yangtze River valley and more precipitation in North China. Compared with the case for the MWP, there was a longer-time-scale southern flood/northern drought phenomenon in 1400-1600. Moreover, the EASM circulation and precipitation did not synchronously vary with the trend of global temperature. During the last 150 years, although the annual mean surface temperature around the world and in China has increased, the EASM circulation and precipitation did not have strengthening or weakening trends. Over the past 1000 years, the weakest EASM occurred ahead of the lowest Northern Hemispheric temperature and corresponded to the weakest solar irradiance. 相似文献
985.
Baroclinic transport and the barotropic effect are two different viewpoints for understanding the mechanism of the Greenland-Scotland Ridge overflow. The mechanism of this overflow, being an important deep branch of thermohaline circulation, deserves research discussion, especially against the background of global warming. Using the newly developed ECHAM5/MPI-OM, of the Max Planck Institute for Meteorology, which is an advanced atmospheresea iceocean coupled climate model, the mechanism of the Greenland-Scotland Ridge overflow variation under different atmospheric CO2 scenarios is studied. First, a control experiment is forced by a fixed CO2 concentration of 280 ppmv, which is the pre-industrial level before 1860. Three sensitive experiments are carried out under different scenarios of increased atmospheric CO2 concentrations, which are listed in the Intergovernmental Panel on Climate Change (IPCC) assessment report (B1, A1B and A2). In the control run, more water with higher salinity intruding into the Greenland-Icelandic-Norwegian Seas results in greater barotropic transport and greater overflow because of the baroclinic effect. Therefore, the barotropic effect and baroclinic effect on the overflow are unified. Under the atmospheric CO2 scenarios, the strength of overflow across the Faro-Bank Channel is controlled by the baroclinic effect and the increase in Denmark Strait overflow is attributed to the barotropic effect. 相似文献
986.
Responses of South and East Asian summer monsoons to different land-sea temperature increases under a warming scenario 总被引:1,自引:0,他引:1
We used outputs from climate models that participated in the fourth assessment (AR4) of the Intergovernmental Panel on Climate Change (IPCC) to evaluate the responses of the South Asian summer monsoon (SASM) and the East Asian summer monsoon (EASM) circulations to different warming over land and ocean under a medium warming scenario, SRES A1B. Our results suggest that, even though near-surface warming over the Tibetan Plateau (TP) is greater than that over the tropical Indian Ocean (TIO) and the northwestern Pacific (NWP), the upper-tropospheric land-sea thermal contrasts between the TP and the TIO (TP-TIO) and between the TP and the NWP (TP-NWP) will decrease. At interdecadal and longer time scales, the change in the SASM circulation is consistent with the TP-TIO upper-troposphere thermal contrast. Conversely, the change in the EASM circulation is consistent with the TP-NWP lower-troposphere thermal contrast. However, at the interannual time scale, both changes in the EASM and SASM are significantly correlated with the upper-troposphere thermal contrast. Further analyses suggest that increases in moisture and changes in cloud cover induced by global warming may cause amplified upper-tropospheric warming over the TP and the oceans resulting in inconsistent changes in the vertical temperature distribution over these regions. Because the warming over the TIO and NWP is greater than that over the TP, the TP-TIO meridional and TP-NWP zonal thermal contrasts will both decrease. However, at the lower layer, the difference in thermal capacity between land and sea result in a larger thermal effect in the near-surface region of the TP than those over the surrounding oceans. We showed that a range of factors that affect thermal conditions will likely cause changes in the Asian monsoon across a range of time scales under a warming scenario. These changes reflect differences in the influence of the greenhouse effect and natural variability. 相似文献
987.
988.
气候变化与玉米生产的响应分析——以1961-2010年开封市玉米生产为例 总被引:2,自引:0,他引:2
采用1961-2010年开封市气象资料、玉米产量资料、农作物受灾资料,分析气候变化对玉米产量的响应.结果表明:在此期间开封市玉米生长期积温与玉米产量均呈上升趋势,二者有明显的正相关关系,积温是气象因子影响玉米产量的主要因素;降水量与玉米产量呈正相上升关系,分析表明开封市玉米生长期的降水量多于玉米生长所需的水分;日照时数... 相似文献
989.
本文采用现场总线监控技术将整个供暖系统中燃煤锅炉、泵房循环泵和公共建筑供热负荷分时段控制集成为一个监控系统。采用模糊PID控制技术优化锅炉运行风煤比,提高锅炉运行效率,采用智能分时分区流量控制技术实现大型公共建筑节能,采用气候补偿技术精确调节锅炉热功率输出。在保证供暖质量的前提下,采用系统节能的方式实现供暖系统最优节能。针对供暖系统电机节能改造带来的谐波污染问题,采用先进的电能质量控制节电技术消除了锅炉房配电系统的谐波污染,达到了节约热能、电能,并且提高电能质量的目的。现场实际运行表明,该技术可行有效,节能效果明显。 相似文献
990.