Based on the sea surface temperature (SST) and sea level pressure (SLP) data, the temporal and spatial variations of sea
surface temperature anomaly (SSTA) in Kuroshio have been analyzed in this paper by means of the method of Rotated
Empirical Orthogonal Function (REOF). The results show that there is a spatial change feature as a whole in addition to
a remarkable interannual/interdecadal change of SSTA. After dividing the positive and negative SSTA years and
analyzing a lot of meteorological elements in corresponding years, it is obtained that the SLP in Kuroshio current region
and the height field at 700 hPa are negative anomaly with enhancement of winter monsoon in the negative years and vice
versa, and that there is a close relation between SSTA of this region and distribution pattern of wind anomaly at 850 hPa.
Due to the significant climatic effects of snow cover, it is very important to improve numerical simulation of snow cover in climate models. With the field data from Col de Porte, Freance and BOREAS, the evolution of seasonal snow cover is simulated with Compreshensive Land Surface Model. The objective of this study is to validate the model and investigate the snow cover proceses in both the alpine regions and the boreal forest. The sensitivity of the simulated results to some model parameters and the different phsyics responsible for the snow cover variation in vegetated and non-vegetated cases are investigated. The modeling results are in good agreements with the observational, and the model represents the snow-pack development and both the timing and the rate of seasonal snowmelt accurately in both cases, indicating that the model has the capacibilty to capture the main features of seasonal snow cover under water holding capacity have significant effects on the simulation of snow cover. The physical processes related to the snow cover variaiotn are different whether vegetation exits or not. Vegetation plays an important role in the dynamics of seasonal snow cover by controlling the radiative fluxes at the snow surface and thus the surface energy balance.
Based on long-time observational datasets, the inter-decadal variations of East Asian summer monsoon (EASM) and summer precipitations over North China together with the relationship between them are investigated by using composite analysis and wavelet transform. Results show that both EASM and summer precipitations over North China have undergone considerable inter-decadal variations over the last 100 years. The Inter-decadal variation of EASM is
characterized by four major strong-weak phases, including two strong EASM periods, that is, the period of 1900~1910 and that from the late 1930s to end of 1960s, as well as two weak EASM periods from late 1910s to the end of 1930s and after 1970s. Corresponding to the inter-decadal variation of EASM, three evident abrupt changes have taken place in 1905, 1948 and 1971 respectively. It has been found that the atmospheric anomalous patterns for strong EASM years are completely distinct from that in weak EASM periods. The inter-decadal variability has been found in the summer precipitations over North China as well. Summer precipitations in North China have gone through four major dry-damp periods, and richer (less) rain periods are in good agreements with strong (weak) EASM periods on inter-decadal scale. Further investigations suggest that summer precipitation anomalies over North China are closely related to the variations of EASM on inter-decadal scale. During stronger (weaker) EASM periods, summer SLP and 500hPa geopotential height both exhibit negative (positive) anomalies over East Asia, implying Indian Low deepens and West Pacific Subtropical High (WSPH) is north (south) than normal. As a result, the North China summer precipitation is richer (less). It is noted that the relationship between precipitation and EASM is changeable with time and also shows inter-decadal features.