Based on a simulation using a newly developed climate system model(Chinese Academy of Sciences-Earth System Model-Climate system component, CAS-ESM-C), the author investigated the Aleutian Low- Icelandic Low Seesaw(AI...Based on a simulation using a newly developed climate system model(Chinese Academy of Sciences-Earth System Model-Climate system component, CAS-ESM-C), the author investigated the Aleutian Low- Icelandic Low Seesaw(AIS) and its decadal variation. Results showed that the CAS-ESM-C can reasonably reproduce not only the spatial distribution of the climatology of sea level pressure(SLP) in winter, but also the AIS and its decadal variation. The period 496–535 of the integration by this model was divided into two sub-periods: 496–515(P1) and 516–535(P2) to further investigate the decadal weakening of the AIS. It was shown that this decadal variation of the AIS is mainly due to the phase transition of the Pacific Decadal Oscillation(PDO), from its positive phase to its negative phase. This transition of the PDO causes the sea surface temperature(SST) in the equatorial eastern(northern) Pacific to cool(warm), resulting in the decadal weakening of mid-latitude westerlies over the North Pacific and North Atlantic. This may be responsible for the weakening of the inverse relation between the Aleutian Low(AL) and the Icelandic Low(IL).展开更多
Based on the NCEP (National Centers for Environmental Prediction) data,the relationship between the Sea Surface Temperature Anomalies (SSTAs) in the North Pacific and the atmospheric circulation anomalies in January 2...Based on the NCEP (National Centers for Environmental Prediction) data,the relationship between the Sea Surface Temperature Anomalies (SSTAs) in the North Pacific and the atmospheric circulation anomalies in January 2008 is analyzed in this study.The SSTA mode most correlated with the Geopotential Height anomalies (GHAs) in January 2008 in the North Pacific exhibited a basin-wide horseshoe pattern with a warm center in November 2007.This persistent SSTA pattern would induce positive GHAs in the Aleutian Low area and East Asia and the northward extension of the West Pacific Subtropical High in January 2008 by maximum diabatic heating in the atmosphere over the Kuroshio Oyashio Extension (KOE) area,leading to the occurence of the circumpolar trough-ridge wave train anomaly in January 2008.展开更多
Kolmogorov's exponential inequalities are basic tools for studying the strong limit theorems such as the classical laws of the iterated logarithm for both independent and dependent random variables. This paper est...Kolmogorov's exponential inequalities are basic tools for studying the strong limit theorems such as the classical laws of the iterated logarithm for both independent and dependent random variables. This paper establishes the Kolmogorov type exponential inequalities of the partial sums of independent random variables as well as negatively dependent random variables under the sub-linear expectations. As applications of the exponential inequalities, the laws of the iterated logarithm in the sense of non-additive capacities are proved for independent or negatively dependent identically distributed random variables with finite second order moments.For deriving a lower bound of an exponential inequality, a central limit theorem is also proved under the sublinear expectation for random variables with only finite variances.展开更多
基金supported by the "Strategic Priority Research Program-Climate Change: Carbon Budget and Related Issues" of the Chinese Academy of Sciences (XDA05110201)the National Basic Research Program of China (2010CB951901)funded by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA05110203)
文摘Based on a simulation using a newly developed climate system model(Chinese Academy of Sciences-Earth System Model-Climate system component, CAS-ESM-C), the author investigated the Aleutian Low- Icelandic Low Seesaw(AIS) and its decadal variation. Results showed that the CAS-ESM-C can reasonably reproduce not only the spatial distribution of the climatology of sea level pressure(SLP) in winter, but also the AIS and its decadal variation. The period 496–535 of the integration by this model was divided into two sub-periods: 496–515(P1) and 516–535(P2) to further investigate the decadal weakening of the AIS. It was shown that this decadal variation of the AIS is mainly due to the phase transition of the Pacific Decadal Oscillation(PDO), from its positive phase to its negative phase. This transition of the PDO causes the sea surface temperature(SST) in the equatorial eastern(northern) Pacific to cool(warm), resulting in the decadal weakening of mid-latitude westerlies over the North Pacific and North Atlantic. This may be responsible for the weakening of the inverse relation between the Aleutian Low(AL) and the Icelandic Low(IL).
基金supported by Chinese NSFC (Grant Nos.40830106 and 40676010)the Ministry of Science and Technology of China (National Key Program for Developing Basic Science,Grant No. 2007CB411803)
文摘Based on the NCEP (National Centers for Environmental Prediction) data,the relationship between the Sea Surface Temperature Anomalies (SSTAs) in the North Pacific and the atmospheric circulation anomalies in January 2008 is analyzed in this study.The SSTA mode most correlated with the Geopotential Height anomalies (GHAs) in January 2008 in the North Pacific exhibited a basin-wide horseshoe pattern with a warm center in November 2007.This persistent SSTA pattern would induce positive GHAs in the Aleutian Low area and East Asia and the northward extension of the West Pacific Subtropical High in January 2008 by maximum diabatic heating in the atmosphere over the Kuroshio Oyashio Extension (KOE) area,leading to the occurence of the circumpolar trough-ridge wave train anomaly in January 2008.
基金supported by National Natural Science Foundation of China (Grant No. 11225104)the National Basic Research Program of China (Grant No. 2015CB352302)the Fundamental Research Funds for the Central Universities
文摘Kolmogorov's exponential inequalities are basic tools for studying the strong limit theorems such as the classical laws of the iterated logarithm for both independent and dependent random variables. This paper establishes the Kolmogorov type exponential inequalities of the partial sums of independent random variables as well as negatively dependent random variables under the sub-linear expectations. As applications of the exponential inequalities, the laws of the iterated logarithm in the sense of non-additive capacities are proved for independent or negatively dependent identically distributed random variables with finite second order moments.For deriving a lower bound of an exponential inequality, a central limit theorem is also proved under the sublinear expectation for random variables with only finite variances.
