面临2000年后全球气温和海面升高的挑战——第四纪气候研究的一项紧要任务

本文论证我国东部第四纪气候变化特征。由于青藏高原的强烈隆起,我国东部于冰期中气候极端干燥而严寒;间冰期及全新世新高温时期,我国华北及内蒙部分地区气温与降水均高于今日。当大气中C_2O倍增时,据GCMs,北半球中伟地带将趋向干燥,美国中西部平原、气温升高,土壤湿度低降,气候干早。本文据我国前一间冰期及全新世新高温时代的气候图象,与太平洋彼岸的下一世纪图象有显著差异。本文运用EOF's函数分析方法研究我国相对海面上升率为3mm/年。由于温室效应引起21世纪气温升高,对我国农作物产量有其有利的一面,而沿海新构造下沉平原区,可能招致严重灾害,应引起我国经济建设决策上的重视,及时作出相应措施。

GRREENHOUSE EFFECRS AND THE IMPACT OF SEA LEVEI RISE AND CLIMATIC CHANGES ON THE NEXT CENTURY

This paper reviews the principal results from palaeoclimate studies and examines the characteristics of Quaternary climatic changes of East China. Owing to the vigorous uplifring of the Tibetan Plateau during the Pleistocene, strong northeast monsoon has prevailed in East and North China and during glacial periods the climate (was) exceptionally cold and dry, The summer monsoon that moved more northward in North China during interglacials caused the climate of interglacials and the Hypisthermal of the Holocene to be warmer and more moist than at present. The palaeoclimatological records provide additional valuable information concerning the possible consequences of a CO_2-induced wdrming, On the basis of the clmatic analogue for the Hypsithermal period, the consequences of a CO_2 warming involve the inrceased precipitation in Norlh China and even in some parts of Inner Mongolia. The results show that the scenario of the future change in precipitation in North China is different from that of the GCMs which indicates that the climate will become drier in the mid-latitude areas including the North American plains that will subject to drought. Another CO_2-induced change may involve an increase of sea level, This paper applies the EOF's mathematical techenique to the study of temporal-spatial field of RSL changes occurring between 1953 and 1980 along the east coast of China, eleven tidal gauge stations were chosen, each of which was examined in such a way that false records could be eliminated, Finally, an average rate of 3mm/year for the RSL rise is indicated, As a direct consequence of sea level rise, large areas of the North China Plain and the delta plains of big rivers, especially the tectonically subsided areas like the Tientsin Plain, the Li shiaho plain as well as the low plain surrounding the Taihu Lake will be inundated by sea water invasion, The sea level rise will also aggravate the potential crisis of the lower reaches of the Yellow River,the river bed of which has been already 8 meters higher than its neighboring plain.