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1.
南极普里兹湾及邻近海域初级生产力的时空变异   总被引:3,自引:0,他引:3  
在南大洋海冰区碳循环的研究中,初级生产力是最重要的基础数据之一.本文就中国南极科考第15、16航次的观测结果,着重讨论普里兹湾及邻近海域初级生产力(PP)的时空变异.第15、16航次生产力的平均测值分别为394.1和271.6 mgC·m-2·d-1,第16航次略低于第15航次.PP的空间分布呈湾内高,湾外低(陆坡、深海区最低)的特征.光合速率的垂直分布呈现次表层极大值型、随深度递减型和极小、极大迭加型3种分布特征,其分布受光照主控.初级生产力在短至1昼夜长达10年的时间尺度内均有显著的变化,初级生产力测值的年际变化最大达2.4倍.  相似文献   

2.
Relationship between the Antarctic oscillation (AAO) and the western North Pacific typhoon number (WNPTN) in the interannual variability is examined in this research. The WNPTN is correlated with the AAO in June-July-August-September (JJAS) in 1949-1998 at -0.48 for the detrended time series, statistically significant at 99% level. The tropical atmospheric circulation as well as the sea surface temperature variability over the western Pacific associated with AAO has been analyzed. It follows that a positive phase of JJAS AAO corresponds to the larger magnitude of the vertical zonal wind shear, the anomalous low-lever anticyclonic circulation and anomalous high-level cyclonic circulation, and lower sea surface temperature in the major typhoon genesis region in the western North Pacific, thus providing unfavorable environment for the typhoon genesis, and vice versa.  相似文献   

3.
 采用季节划分和季节突变的概念、理论及方法,对44a(1958~2001年)的大气臭氧资料及对流层顶气压场资料进行了计算,并分析了对流层顶大气臭氧的季节变化.结果发现对流层顶大气臭氧的季节变化在全球大部分区域中的突变性都比较明显,表明对流层顶大气臭氧的季节变化受到上对流层和下平流层中多种因素的影响.通过分析还发现,利用曾庆存所定义的参数RW(t)及有关的一些概念和方法确能很好地反映对流层顶大气臭氧的季节变化.  相似文献   

4.
对全球网格点大气臭氧总量的卫星观测数据进行了分析,结果表明:大气臭氧总量有明显的准两年周期振荡(QBO),且准两年周期振荡从低纬度地区向高纬度地区传播;大气臭氧的QBO存在一定的纬圈结构,局部地区的QBO有从高纬度地区向低纬度地区传播的现象.  相似文献   

5.
卫星遥感监测大气臭氧总量分布和变化   总被引:1,自引:0,他引:1  
 利用卫星紫外仪器TOMS、OMI和TOU的臭氧总量数据(1979-2014年),研究了全球及关键地区臭氧总量的分布及变化。讨论了南北半球臭氧总量分布和变化的差异,探讨了影响臭氧分布和变化的可能因子。重点分析了中国区域、青藏高原和极地的臭氧变化,并利用FY-3数据对南极臭氧洞和北极臭氧低值进行了监测。结果表明,臭氧总量的分布和变化在中高纬度地区具有很强的不均匀性,极地臭氧损耗依然明显,青藏高原的臭氧增长大于同纬度其他地区,其机制更加复杂。  相似文献   

6.
为了研究厄尔尼诺和南方涛动(ENSO)现象影响热带大气季节内振荡(ISO)的年代际变化特征,利用奇异值分解(SVD)、小波分析和经验正交函数分析(EOF)等方法对热带大气ISO强度指数、赤道中东太平洋海温及热带大气环流场进行了分析。计算结果显示,20世纪70年代中期以前,ENSO对热带大气ISO的影响较弱;70年代中期以后,ENSO对热带大气ISO的影响加强。造成上述年代际变化的原因与热带大气环流的年代际变化有关,因此,ENSO对热带大气ISO的影响也存在年代际变化。  相似文献   

7.
Surface ozone concentration and UV-B data between 75° N and 70° S were obtained aboard the Chinese polar scientific vessel “Xue -long” (Snow-Dragon) during the first voyage to the Arctic and the 16th to the Antarctic in 1999–2000. Analysis of these data presents that variations of the surface ozone concentration have small amplitude during voyages except the mid-latitude in the Northern Hemisphere. As a whole, average surface ozone concentration in the Northern Hemisphere is higher than that in the Southern, and high value occurred when the ship sailed close to the continents. The average diurnal variations of the surface ozone in the Northern Hemisphere are also higher compared to the southern counterparts, and high diurnal variations were found at low latitudes, and relative low level in the polar region.  相似文献   

8.
 利用ECMWF 195709~200208共45a的多层臭氧质量混合比月平均资料,详细分析了亚印太交汇区(AIPO)低纬地带上空平流层、对流层各层次上臭氧浓度的分布特征.结果表明:①区域上空对流层、平流层及臭氧总量大尺度特征均显著,纬度带分布特征明显;②对流层和平流层臭氧各个季节变化趋势相反,平流层臭氧和臭氧总量各个季节变化趋势一致;同一层次夏季臭氧浓度变化趋势与其他3个季节变化趋势相反;③区域上空20~3hPa是臭氧浓度的高值区,50~30hPa臭氧平均变化幅度最大;④对流层臭氧距平变化在整个高度上较为一致,正、负距平随季节绕赤道做南、北半球摆动,且存在季节性突变;⑤赤道上空有明显从平流层上层随季节逐渐往较低层传播的臭氧正负距平现象.  相似文献   

9.
Both correlation analysis and case study indicate that Antarctic oscillation (AAO) is closely related with summer rainfall in eastern China. When AAO is stronger in boreal spring, especially in May, there is more mei-yu rainfall in summer with a longer period along the Yangtze and Huaihe River valley. In contrast, there is less rainfall with a shorter period corresponding to a weaker AAO. Besides, an anomalous AAO changes the position and intensity of several circulation systems, which are important to summer rainfall along the Yangtze and Huaihe River valley. Furthermore, the Antarctic sea ice is negatively correlated with the intensity of AAO with a 6-month leading time. The result in this study provides a new method for the prediction of mei-yu.  相似文献   

10.
【目的】近地层臭氧(O3)是具有强氧化性的二次污染物,可损伤植物内部结构和生理功能,造成作物生长量和品质下降。了解不同大气O3浓度下樱桃萝卜各生长时期的叶片受害和生物量状况,分析其受害症状、生物量与O3暴露剂量之间的相关关系,为探讨O3浓度升高对农作物产量的影响及作物大气O3标准的制定提供参考。【方法】利用12个生长室设置了4个大气臭氧(O3)浓度(30、50、70和90 nmol/mol),对樱桃萝卜叶片的受害症状和第7、14、21和28天的生长和生物量变化进行了研究,并拟合计算了O3暴露剂量AOT40和叶片受害症状、生物量变化间的相关关系。【结果】① 70和90 nmol/mol O3处理下,第7天观测发现樱桃萝卜子叶上部出现褪绿斑点, 整叶局部薄厚不均,叶片受害症状随着O3熏蒸时间的增加而加重,出现O3受害症状的叶片比例和O3暴露剂量AOT40极显著相关 (P<0.01)。②处理第21天时观测发现,O3熏蒸均对樱桃萝卜整体干质量产生影响;与30 nmol/mol处理的相比,第28天时观察发现,50、70和90 nmol/mol O3处理后的樱桃萝卜肉质根干质量分别下降了45.1%、57.3% 和79.9%。干质量下降的幅度大于体积的,肉质根体积和干物质量都与O3暴露剂量AOT40线性相关。【结论】樱桃萝卜的生长和生物量受到O3浓度和累积时间两个因素共同影响,O3浓度升高显著抑制了樱桃萝卜生长,造成叶片受损,可食用肉质根体积和总干物质量显著下降。  相似文献   

11.
冬季Hadley环流活动与大气臭氧变化的关系研究   总被引:1,自引:0,他引:1  
 利用1957年9月到2002年8月,共540个月的ECMWF的经向风和臭氧质量混合比资料,分析研究了冬季Hadley环流强弱特征的变化对臭氧变化的影响.分析指出在冬季伴随Hadley环流的增强,其中心南移,高度升高,臭氧在对流层增加,平流层减少,臭氧总量呈现出减少的趋势.Hadley环流的增强,中心南移,高度升高以及臭氧在对流层的增加对全球变暖是正反馈,而平流层臭氧减少,臭氧总量减少对全球变暖是负反馈.因此Hadley环流的强弱对臭氧的影响明显.  相似文献   

12.
Data from FY-3B SBUS and NOAA SBUV/2 were used to monitor ozone levels in the Arctic region from March 1 to April 5, 2011. Results revealed a significant ozone depletion in the area, with total ozone levels between 200–250 DU. The ozone levels recorded were 100–200 DU below normal, and in some parts the levels were as low as 200 DU, indicating a mini ozone-hole. During the sampling period, the ozone depletion area underwent identifiable expansion and detraction, a rotation around the North Pole from the west to the east, and a longitudinal movement from the Pole, spreading to the mid latitudes. The effects of these rare low ozone events were not only felt in the Arctic, but also extended to densely populated areas between Europe and the middle of Russia. In this region, rapidly increasing levels of ultraviolet radiation were detected at the Earth’s surface. Given the significant risk that this poses to both the environment and people’s health, this occurrence has significant global implications.  相似文献   

13.
14.
采用交叉谱分析方法,通过年全球平均的大气臭氧总量和10.7cm大阳通量两时间序列的对比分析发现,大气臭氧的短期变化和大阳自转活动之间有着极为密切的相关关系:大气臭氧准27天周期变化和太阳10.7cm辐射通量之间存在约140°的位相差,落后时间为10.2天.//关键词  相似文献   

15.
Variations in global atmospheric oscillations during the last millennium are simulated using the climate system model FGOALS_gl. The model was driven by reconstructions of both natural forcing (solar variability and volcanic aerosol) and anthropogenic forcing (greenhouse gases and sulfate aerosol). The model results are compared against proxy reconstruction data. The reconstructed North Atlantic Oscillation (NAO) was out of phase with the Pacific Decadal Oscillation (PDO) in the last millennium. During the ...  相似文献   

16.
提出一种利用地形海拔落差以及臭氧总量差来估算对流层低层大气臭氧浓度的方法.根据搭载于美国宇航局Aura卫星上的臭氧监测仪(OMI)提供的臭氧总量日观测数据,利用该方法计算出青藏高原与其周边地区四川盆地及印度北部的地形海拔落差及臭氧总量差,进一步分析了该地区低层大气臭氧的分布特征.结果表明:青藏高原周边地区对流层低层大气臭氧分布呈明显的季节变化,且低层大气臭氧分布有南北差异,南部臭氧含量高于北部.  相似文献   

17.
介绍了英国科学家法曼发现南极臭氧层空洞的过程,以及美国宇航局(NASA)的科研人员在这个问题上的失误,并简要介绍了日本学者忠钵繁所做的贡献。阐述了南极臭氧层空洞发现过程带给我们的启示:试验条件的优劣不是决定科学发现的唯一因素;期刊的知名度决定着文献的影响力。  相似文献   

18.
The Beijing-Tianjin-Hebei Atmospheric Environment Monitoring Network was established by the Institute of Atmospheric Physics, Chinese Academy of Sciences. The goals of the network were to monitor and provide warnings of the atmospheric quality in Beijing and its surrounding area during the Beijing 2008 Olympic Games. The results showed that the atmospheric complex pollution exhibited high concentrations of ozone and fine particles and oxidation in summer, with a ubiquitous regional source. The regional mean concentrations of SO2, PM2.5, NO2, and O3_8h max (the maximum daily 8 h mean) and Ox were 22±11, 90±40, 25±5, 136±35 and 112±21 μg/m3 in summer, respectively. During the Olympic Games, the mean concentration of SO2, PM2.5, NO2, O3_8h max, and Ox were 12.5±4, 56±28, 23±4, 114±29, 95±17 μg/m3 in the region, respectively, and fell by 51.0%, 43.7%, 13%, 20.2%, and 18.9%, respectively, compared to the prophase mean before the Olympic Games. The concentration of atmospheric pollutants declined significantly and achieved the “Green Olympics” control goal of air quality. After the Olympic Games, SO2, PM2.5 and NOx increased significantly as the temporary atmospheric pollution control measures were terminated.  相似文献   

19.
平流层CH4的时空变化特征及其与O3的关系   总被引:2,自引:0,他引:2  
 利用1991年10月到2005年11月的HALO3E卫星观测资料,对全球70°S~70°N范围内平流层100hPa到1 hPa的大气CH4混合比进行了时空特征分析.结果表明:①CH4混合比在平流层是随高度上升而逐渐减小的.平流层中上层CH4变化存在年循环,而平流层中下层CH4变化存在半年振荡(SAO3),且南半球平流层CH4的季节变化振幅要大于北半球,特别是平流层中上层.平流层各个高度上的CH4基本呈纬向分布,但是不同高度上分布特征有所差异;②平流层CH4混合比变化存在3个月,10个月,准25个月和准45个月左右时间尺度的周期,但是3个月的短期变化和10个月的年循环只在1996年之前明显;③不同高度上,CH4和O3变化的相关关系是不同的,CH4对O3的破坏作用并不是存在于整个平流层,似乎是在有的高度上相关关系明显,有的高度上相关关系不明显.  相似文献   

20.
Based on NCEP/NCAR monthly mean reanalysis data and surface observations of Chinese stations, inter-hemispheric oscillations (IHO) of spring atmospheric mass on an interannual basis in conjunction with the linkage to the synchronous climate over China are studied. Results suggest that the spring IHO exhibits a significant seesaw pattern for air mass at bi-hemispheric mid-high latitudes, with a consistent vertical circulation structure. The EOF decomposition of zonally mean surface pressures without signals of Arctic Oscillation (AO) and Antarctic Oscillation (AAO) indicates that the EOF1 IHO feature is remarkable, with the corresponding time coefficients correlated with the spring IHO index (IIHO) at 0.93; the spring IHO bears a close relation to the synchronous climate in China, showing the surface pressure, temperature and relative humidity over the country to be in good correlation with IIHO; the spring duststorms in Qinghai, Gansu, Shaanxi and Inner Mongolia have bearing on IHO. Positive-phase IIHO promotes the strengthening of the Siberian high, during which zonal winds between 60°E and 150°W show a longitudinal teleconnection structure extending from the Arctic to Antarctica, leading to positive westerly wind anomalies over Asia, affecting the spring climate of China.  相似文献   

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