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201.
CO2地质封存是减少温室气体向大气排放的有效措施之一,而深部咸含水层CO2地质封存是目前可行的最有潜力的封存技术。先前研究表明,松辽盆地是一个潜在的封存场地。基于对松辽盆地地质资料的初步分析,选取三肇凹陷的姚家组1段和青山口组2、3段地层作为CO2的注入层,建立一个典型二维模型,研究CO2注入后的迁移规律。结果表明,CO2注入后会向上和侧向迁移,后期可能出现的对流作用能促进CO2的溶解。残留气体饱和度、注入层水平和垂直渗透率的比值对模拟结果影响最大。此外,储层中的薄页岩夹层有利于CO2的溶解,因此,在保证注入性和封存量的情况下,储层中低渗透性夹层是允许的。 相似文献
202.
Potential changes in precipitation extremes in July–August over China in response to CO 2 doubling are analyzed based on the output of 24 coupled climate models from the Twentieth-Century Climate in Coupled Models (20C3M) experiment and the 1% per year CO 2 increase experiment (to doubling) (1pctto2x) of phase 3 of the Coupled Model Inter-comparison Project (CMIP3). Evaluation of the models’ performance in simulating the mean state shows that the majority of models fairly reproduce the broad spatial pattern of observed precipitation. However, all the models underestimate extreme precipitation by ~50%. The spread among the models over the Tibetan Plateau is ~2–3 times larger than that over the other areas. Models with higher resolution generally perform better than those with lower resolutions in terms of spatial pattern and precipitation amount. Under the 1pctto2x scenario, the ratio between the absolute value of MME extreme precipitation change and model spread is larger than that of total precipitation, indicating a relatively robust change of extremes. The change of extreme precipitation is more homogeneous than the total precipitation. Analysis on the output of Geophysical Fluid Dynamics Laboratory coupled climate model version 2.1 (GFDL-CM2.1) indicates that the spatially consistent increase of surface temperature and water vapor content contribute to the large increase of extreme precipitation over contiguous China, which follows the Clausius–Clapeyron relationship. Whereas, the meridionally tri-polar pattern of mean precipitation change over eastern China is dominated by the change of water vapor convergence, which is determined by the response of monsoon circulation to global warming. 相似文献
203.
This is the second part of the authors’ analysis on the output of 24 coupled climate models from the Twentieth-Century Climate in Coupled Models (20C3M) experiment and 1% per year CO 2 increase experiment (to doubling) (1pctto2x) of phase 3 of the Coupled Model Inter-comparison Project (CMIP3). The study focuses on the potential changes of July–August temperature extremes over China. The pattern correlation coefficients of the simulated temperature with the observations are 0.6–0.9, which are higher than the results for precipitation. However, most models have cold bias compared to observation, with a larger cold bias over western China (>5°C) than over eastern China (<2°C). The multi-model ensemble (MME) exhibits a significant increase of temperature under the 1pctto2x scenario. The amplitude of the MME warming shows a northwest–southeast decreasing gradient. The warming spread among the models (~1°C– 2°C) is less than MME warming (~2°C–4°C), indicating a relatively robust temperature change under CO 2 doubling. Further analysis of Geophysical Fluid Dynamics Laboratory coupled climate model version 2.1 (GFDL-CM2.1) simulations suggests that the warming pattern may be related to heat transport by summer monsoons. The contrast of cloud effects also has contributions. The different vertical structures of warming over northwestern China and southeastern China may be attributed to the different natures of vertical circulations. The deep, moist convection over southeastern China is an effective mechanism for "transporting" the warming upward, leading to more upper-level warming. In northwestern China, the warming is more surface-orientated, possibly due to the shallow, dry convection. 相似文献
204.
运用Mapsis软件前兆异常分析中的差分和从属函数,对新04号泉溶解气CO2进行异常识别,结果认为:①差分和从属函数异常形态均为高值异常;②差分异常对近场中强震和远场强震的映震率均为71.4%(5/7);从属函数异常对近场中强震的映震率为66.7%,而对远场强震的映震率为83.3%(5/6);两者均出现异常时,对近场中... 相似文献
205.
Seasonality changes in China under elevated atmospheric CO 2 concentrations were simulated using nine global climate models,assuming a 1% per year increase in atmospheric CO 2.Simulations of 20th century experiments of season changes in China from the periods 1961 80 to 1981 2000 were also assessed using the same models.The results show that the ensemble mean simulation of the nine models performs better than that of an individual model simulation.Compared the mean climatology of the last 20 years in the CO 2-quadrupling experiments with that in the CO 2-doubling ones,the ensemble mean results show that the hottest/coldest continuous-90-day (local summer/winter) mean temperature increased by 3.4/4.5°C,2.7/2.9°C,and 2.9/4.1°C in Northeast (NE),Southwest (SW),and Southeast (SE) China,respectively,indicating a weakening seasonal amplitude (SA),but by 4.4/4.0°C in Northwest (NW) China,indicating an enlarging SA.The local summer lengthened by 37/30/66/54 days in NW,NE,SW,and SE China,respectively.In some models,the winter disappeared during the CO 2-quadrupling period,judging by the threshold based on the CO 2-doubling period.The average of the other model simulations show that the local winter shortened by 42/36/61/44 days respectively,in the previously mentioned regions. 相似文献
206.
运用热力学原理和方法,研究了CO2-H2O流体不混溶作用对Au的溶解度的影响。结果表明,贵州水银洞金矿床的成矿流体是一种富含挥发分(fCO2=70.79MPa)、酸性(pH=3.71)、还原性(fO2=0.50×10-36MPa)、中温(267℃)、具有超压(180MPa)性质的含Au(a∑Au=3.744×10-8mol/L)流体。当超压流体的封闭层——炭质页岩因断裂作用而被破坏时,热液体系的压力发生骤降(28.50~35.30MPa),CO2-H2O流体发生不混溶作用,并有大量CO2溢出。CO2的流失可使成矿溶液的CO2逸度和O2逸度降低(fCO2=0.80MPa、fO2=2.512×10-42MPa),酸碱度升高(pH=4.32),同时伴随温度的下降(224℃),成矿热液中Au溶解度的降低(a∑Au=3.790×10-9mol/L),从而快速沉淀下来成矿。 相似文献
207.
208.
Dark respiration (non-photorespiratory mitochondrial respiration),which occurs both in the light and in darkness,is vital for growth and survival of algae and plays a critical role in modulating the carbon balance of them.In the present study,we have investigated dark respiration in the light (R L) and in darkness (R D) in three marine macroalgal species,Hizikia fusiformis (phaeophyta),Gracilaria lemaneiformis (Rhodophyta) and Ulva lactuca (Chlorophyta),cultured at 20℃ using aeration with two CO 2 conditions:current ambient (CO 2 concentration about 380 μl/L) and elevated CO 2 (approximately 720 μl/L) air.R L was estimated by using the Kok method,whereas R D was determined as the rate of O 2 influx at zero light.The results showed that both R L and R D were unchanged for the elevated CO 2-grown algae relative to ambient CO 2 concentration for all the algal species tested.However,R L was significantly lower than R D across all the algal species and growth CO 2 treatments,demonstrating that daytime respiration was partly depressed by the light.The percentage of inhibition of respiration by light was similar between ambient and elevated CO 2 grown algae.The ratio of respiration to photosynthesis,which tended to decrease when estimated using R L instead of R D,was not altered for the elevated relative to ambient CO 2 concentration.The results suggest that R L,rather than R D,is a more accurate estimate of nonphotorespiratory carbon loss in marine macroalgae during the daytime.It would not be anticipated that elevated atmospheric CO 2 would exert a substantial influence on respiratory flux either in the light or in darkness in these particular marine macroalgal species. 相似文献
209.
利用AIRS产品数据提取了2010年4月4日墨西哥下加利福尼亚MW7.2地震前后震中及其附近CO总量和CO体积混合比随时间变化的信息,讨论了CO气体地球化学变化与地震活动的关系。数据表明,下加利福尼亚地震前约一个月CO总量升高,高出前两年同期平均值2~4×1017 mole/cm2,在地震发生前后CO总量和近地表CO体积混合比有波动现象,且8日平均数据的标准偏差增大,约为非地震时段的2倍。该现象应该归因于地震孕育发生过程中地应力作用使岩石圈脱气增强、大气电磁和化学反应引起的CO含量的增加。研究结果表明利用卫星高光谱遥感数据提取与地震有关的CO气体地球化学信息,对地震监测预报有重要意义。 相似文献
210.
低渗透油藏CO2驱过程中含水率变化规律 总被引:1,自引:0,他引:1
通过国内外多个油田水驱后实施CO2驱的矿场实例研究,发现注入CO2后很多油井存在含水率下降的现象;这种现象发生在CO2驱的整个开发阶段,包括注气初期阶段CO2未到达生产井、生产井见气阶段以及高气油比阶段。重点讨论了生产井见气前的开发规律,在该阶段油藏内以油水两相渗流为主,不受三相渗流作用的影响。通过现场动态反应并结合室内细管和长岩心实验,揭示了CO2与油、水2种介质的相互作用,得到了两个结论:第一是始于低含水阶段的CO2驱过程中气体穿越地层水驱替地层油到达生产井;第二是始于高含水阶段的CO2驱替规律在不同级别低渗透岩心中的差异非常明显:对于特低渗岩心,CO2突破前的采出程度占CO2驱总采出程度的73.27%,CO2突破后的采出程度占26.73%,对于一般低渗岩心,CO2突破前的采出程度仅占CO2驱总采出程度的16.72%,而CO2突破后的采出程度占到了CO2驱总采出程度的83.28%。 相似文献