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221.
首先分析了Wang的有关行星反照率假设的错误之处,而后分别对Budyko、North的行星反照率假设提出修改方案,最后提出了有关行星反照率的非线性分段、反馈假设: 相似文献
222.
The method for determining Pco2 in the atmosphere and water by using gas chroma-tography was studied. For determination of Pco2 in the atmosphere, a sampling method was developed in which the chromatograph was connected to a 6-port valve with a sampling pipe opening to the atmosphere, so gas pressure in the sampling pipe was identical to that of the atmoesphere. A semi-automatic seawater-atmosphere equilibrium system was designed to determine the Pco2 in seawater. The equilibrium chamber contained in situ seawater and the well-equilibrated gas was pushed into the sampling pipe by sample wa-ter, so pressure and temperature calibration could be avoided. This method has high accuracy for the de-termination of Pco2 in the air and seawater, and was used for in situ determination of Pco2 in the atmo-sphere and of the seawater sample in the JGOFS cruise in the East China Sea. 相似文献
223.
Yanfeng Liu Xiaohui Lu 《中国地球化学学报》2006,25(B08):280-280
It has been proved to be one effective means to reduce emissions of CO2 to mitigate the worsening global climate change through lots of projects and tests about CO2 geological storage. The sites that are suitable for CO2 geological storage include coal seams that can not be mined, deep saline aquifers, oil fields, and depleted gas fields. The emission of CO2 from fuel combustion is about 3.54 Gt in China in 2003, which is the second biggest in the world. Because the energy consumption in China mainly depends on fossil fuels for a long time in the future, China will become a country with the biggest emission of CO2 in the world, which will make China have to reduce the emissions of CO2 by some methods including geological storage. Based on lots of information about the reserves of coal seam methane and the rank of coal in the 68 coal basins in China, the total CO2 storage capacity in these coal basins was estimated according to the recovery coefficient and exchange ratio of CO2 to CHa.The total storage capacity in deep saline aquifers can be regarded as the total quantity of CO2 that can be dissolved in the saline aquifers at the depth from 1000m to 3000m under ground. The quantity can be estimated by multiplying the solubility of CO2 in the saline water and the volume of the appropriate aquifers. According to the reserve and quality of crude oil in 46 main oil basins in China, the CO2 storage capacity and the quantity of enhanced oil were calculated. The storage capacity of depleted gas fields can be derived from the reserve and depth of the gas fields. The total CO2 geological storage capacity is about 196.2 Gt CO2 that is as against 55.4 times the CO2 emission from fuel combustion in China in 2003. According to the results of the finished projects and tests about CO2-EOR and CO2-ECBM, the CO2 geological storage capacities in coal seams, deep saline aquifers, oil fields and depleted gas fields will be estimated. 相似文献
224.
225.
科学家公认“生命宜居带”是恒星周围的一个区域,其中液态水必须能够在一个类地行星的表面存在数十亿年之久;这个区域是环形的,它的内边界应该是行星围绕其母恒星运转而又不会使行星海洋的水散失到空间的最近一条轨道;在最极端的情况下,恶性发展的温室效应将占支配地位,结果使得海洋水蒸发殆尽(例如金星正是此种情况)。 相似文献
226.
四川盆地温室效应的研究具有丰富的地球科学意义,并且对农业生产和农业科学研究具有指导作用。为此,建议应尽早调查盆地当今和历史温室气体的排放率以及大气的化学组成情况;研究近几万年来以盆地古气候的变化特点。建议并指出该项研究的关键问题是寻求盆地近百年气候变化与温室气体的统计关系,同时预测21世纪中期前四川盆地未来气候的变化趋势。 相似文献
227.
对塔里木盆地21条河流代表站的水文资料用秩次相关法分析近年来该盆地主要河流年迳流量的变化趋势。分析表明有上升、下降、平稳等三种类型。这与补给类型有关,但与近年气候变化引起径流量变化的相关不显著。 相似文献
228.
A case study was performed in Beijing in 2000 to observe concentrations of SO2 and NOx in the atmosphere and to evaluate their radiative impact. It was found that the concentrations of these gases are usually high in the morning due to a temperature inversion in the boundary layer. The average concentrations obtained from the observations are much higher than those used in the McClatchey reference atmosphere. The radiative impacts of these gases are calculated using a line-by-line radiative transfer model. The results show that the radiative forcing at the surface due to SO2 is 0.0576 W m-2 and that due to NOx is 0.0032 W m-2. These figures are almost compatible with that due to CFC11. 相似文献
229.
使用宜昌市气象台1951-2000年气温观测资料,对宜昌市城区(以下简称宜昌)近50年气温滑动平均时间序列进行了线性拟合。其结果表明:(1)宜昌冬季气温有所上升,夏季气温略有下降,春、秋两季及年平均气温变化不明显;(2)宜昌近50年气温,其前期变化趋势与全国范围的基本同步。经R/S分析发现,宜昌目前的冬暖夏凉气候格局在未来一段时间仍将持续,而其年平均气温变化平缓的趋势则有可能在未来发生改变。 相似文献
230.
中国地区云对地气系统长波射出辐射(OLR)强迫的气候研究 总被引:1,自引:0,他引:1
本文利用地球辐射平衡试验(ERBE)和国际卫星去气候计划(ISCCP)提供的地气系统长波射出辐射(OLR)和云量资料,计算半讲座了我国各季和年平均去量对地气系统OLR的强迫及其所产生的温室效应,结果表明:我国各季的OLR云强迫与总云量,高云量都有较好的相关,且季节变化明显;OLR云强迫和云温室效应的地理分布受云量和云状的影响较大,它们的年变化一般呈弱双峰型,峰值在春,夏季出现。 相似文献