对流层顶气压与气温的年(代)际变率研究:冬季特征

利用NCEP／NCAR再分析月平均对流层顶气压、气温资料，研究了1979-2002年冬季全球对流层顶气压、气温的年际和年代际变率。选取了冬季对流层项变率最大的区域来定义气压指数、气温指数。通过分析得到：（1）全球对流层项气压、气温随纬度的增加而增高，但在整个热带地区和高纬度地区对流层顶气压、气温的分布较均匀。在分析时段内全球平均的对流层顶气压呈下降趋势，气温呈降低趋势。这些从全球资料得到的结果支持了已有的从部分探空资料所得到的结果。（2）对流层顶变率最大值出现在北半球的副热带地区，最小值出现在低纬度地区。气压指数和气温指数显示出准13a及准3～6a的周期。在1992年以前准3a的周期变化较强，1989年后准6a较强，显示出年际变化的年代际差异。对流层项气压与对流层顶气温在全球大部分地区都呈显著正相关，但在热带和副极地的部分地区相关较弱。对流层顶气压与对流层平均气温在全球大部分地区都呈显著负相关，但在极地地区有正相关关系，显示了对流层顶与对流层内部变化关系的复杂性。     

极地越冬食品保障——关于南极科考越冬食用蔬菜问题

蔬菜是人们摄取各种营养成分主要来源之一,由于南极的特殊环境,科考队员所需的各种营养成分很难得到满足。为重视、解决这一问题,文中详细讨论了选用传统东北人冬季食用蔬菜制品,代替南极科考队的越冬食用蔬菜,来满足生理需要。     

High-resolution peat records for Holocene monsoon history in the eastern Tibetan Plateau

Holocene peat sediment has been attached impor-tance to reconstruct the Holocene climatic variations because it can provide much palaeoclimatic informa-tion with high resolution. Analysis on the plant mac-rofossil[1], pollen[2―4], isotope ratio[5―9], element con-tent[10,11], total organic carbon (TOC)[12], humifica-tion[13,14] and grayscale[12] for peat sediment has shown its superiorities as a recorder medium for reconstruct-ing the Holocene climate. Hong et al. have done great fruitful w…     

欧亚积雪异常分布对冬季大气环流的影响I. 观测研究

利用ECMWF 1979～1993年2.5°×2.5°的网格点积雪深度资料、中国气象局整编的海平面气压、500 hPa高度场和NCEP再分析资料,探讨了欧亚冬季积雪异常对同期大气环流的影响.结果表明:(1) 欧亚中高纬冬季积雪面积与同期大气环流具有密切的联系:积雪面积为正(负)异常时,冬季500 hPa高度场对应正(负)欧亚-太平洋(简称EUP)遥相关型,东亚冬季风活动偏强(弱).(2)诊断结果表明,积雪异常与大气环流之间的密切联系在一定程度上反映了冬季积雪的异常分布可能对大气EUP遥相关型和东亚冬季风活动产生影响.(3)SVD分析得到的冬季积雪的异常分布与同期大气环流的耦合模态,证实了前面所得结果.     

INTERRELATION BETWEEN EAST-ASIAN WINTER MONSOON AND INDIAN/PACIFIC SST WITH THE INTERDECADAL VARIATION*

Investigated statistically is the interrelation between East Asian winter monsoon (EAWM) and SST over sensitive areas of the Indian and Pacific Oceans.with focus on the relation of EAWM to strong ENSO signal area.i.e.,the equatorial eastern Pacific (EEP) SST.Evidence suggests that the EAWM variation is intimately associated not only with the EEP SST but with the equatorial western Pacific "warm pool" and equatorial Indian/northwestern Pacific Kuroshio SST as well:the EAWM and ENSO interact strongly with each other on the interannual time scales,exhibiting pronounced interdecadal variation mainly under the joint effect of the monsoon QBO and the monsoon/SST background field features on an interdecadal basis-when both fields are in the same phase(anti-phase).strong EAWM contributes to EEP SST rise(drop)in the following winter,corresponding to a warm(cold)ENSO cycle;the EAWM QBO causes ENSO cycle to be strong phase-locked with seasonal variation,making the EEP SST rise lasting from April-May to May-June of the next year,which plays an important role in maintaining a warm ENSO phase.     

冬小麦风雹灾害的等级划分与灾情评估

以冬小麦的风雹灾害为研究对象,从１９８１～１９９０年３３个冰雹个例中选取与冬小麦生长有关的１７个个例,以冰雹直径、降雹时间、降雹时阵风为因子,对冬小麦风雹灾害进行等级划分及灾情评估。应用证明,这些研究对提高农业灾害的管理水平具有重要意义。     

甘肃西峰冬小麦土壤水分动态及其对作物产量影响

本文利用甘肃省西峰市农业气象试验站非灌溉地冬小麦田间土壤水分资料、气候资料,分析了不同年型农田土壤水分的时空变化特征,从土壤水分平衡方程出发,讨论了冬小麦返青至成熟期间降水量、作物耗水量、渗漏量和土壤储水量变化各平衡分量的动态变化及其相互关系。对冬小麦产量与不同作物发育期的作物耗水量之间进行相关普查,结果表明影响小麦产量最显著的时段是拔节～孕穗期。分别运用物理统计和经验统计方法建立了冬小麦产量与作物耗水量的关系模型,认为后者模拟效果较好。     

DIAGNOSTIC ANALYSIS OF THE INFLUENCE OF ANOMALOUS SURFACE SENSIBLE HEAT FLUX IN THE TIBETAN PLATEAU AND ITS VICINITY ON THE EAST ASIAN WINTER MONSOON*

Based on NCEP/NCAR reanalysis monthly data,the relation between the surface sensible heat flux,(SHTFL) in the Tibetan Plateau and its vicinity and the East Asian winter monsoon is revealed as follows:on the inter-annual and longer time scales,the difference between SHTFL anomalies in the east and southern slope of the Tibetan Plateau last spring has influence on the East Asian winter monsoon,that is,SHTFL anomaly in the east of the Tibetan Plateau was positive and that in the southern slope was negative last spring,then the East Asian winter monsoon would become more vigorous,and vice versa.Both the most significant period of the difference between SHTFL anomalies in the east and southern slope of the Tibetan Plateau and that of the East Asian winter monsoon index are 2 to 4-year time scales.On the 2 to 4-year time scales,the heterogeneous spatial distribution of SHTFL anomalies in the east and southern slope of the Tibetan Plateau last spring has effect on the East Asian winter monsoon,after SHTFL anomaly in the east of the Tibetan Plateau was positive and that in the southern slope was negative last spring,then the East Asian winter monsoon would be more powerful,and vice versa.The lag influence of the difference of SHTFL anomalies in the east and southern slope of the Tibetan Plateau on the East Asian winter monsoon brings into effect mainly on 2 to 4-year time scales.In the end an reasonable explanation for their relationship has been discussed.     

冬季北半球500hPa高度场变异的关键区

运用方差分析、相关分析、回归分析对1951～2001年500 hPa高度场资料进行分析,结果表明:冬季有三个区域(180°E～150°W,45～60°N;70～100°W,45～75°N;60～100°E,65～80°N)方差最大,是大气环流发生变异的关键区.各个关键区平均高度的变化和不同的大气环流遥相关型的相关关系不同,与同期500 hPa高度场之间的线性相关较密切,能代表同期500 hPa高度场约88%的变化,且在一定程度上能说明后期3～4月的500hPa大气环流的变化情况,对后期大气环流的演变具有一定的预报意义,但时间间隔越大,可预报性越差.     

干旱综合防御技术对小麦生长和产量的影响

1998年10月至2000年6月进行的冬小麦大干旱综合防御技术集成试验表明，充足的底墒水、深耕、秸杆翻压还田、秸杆覆盖、喷施防旱剂和有限灌溉等是防御冬小麦干旱、减少土壤水分无效消耗的有效措施，对小麦叶面积、干物重和产量形成有明显的影响。综合运用以上措施，可使冬小麦叶面积、干物重和产量形成有明显的影响。综合运用以上措施，可使冬小麦增产10％以上，水分利用效率提高30％以上，每公顷增收节支500－800元。