Reconstructions of past climate based on pollen data have formed a robust approach and produced a great of products in time scales from a millennium to ten millenniums. However, it is an attempt for reconstruction of ...Reconstructions of past climate based on pollen data have formed a robust approach and produced a great of products in time scales from a millennium to ten millenniums. However, it is an attempt for reconstruction of the past decade-century climate in the Global Change field. This note reports a reconstruction of the past 1000-a temperature in a 50-a scale in Canada based on pollen data. Because there were little human activities during the last 1000 years in North America, the climate in the period mainly responded to natural changes. The reconstruction of a natural-forcing change in the climate can provide a basis to recognize the climate changes impacted from human activities in China. The technique of modern analogue can be implemented to reconstruct the past millennium climate in China.展开更多
利用吕宋海峡附近海区温盐数据的数值模型进行声传播模拟计算的方法,根据相应的声速剖面及声传播损失,分析台风对声传播特性的影响。结果显示,2010年第10号台风"莫兰蒂"过境时,海洋环境对台风的响应较为迅速,海洋表层的温度...利用吕宋海峡附近海区温盐数据的数值模型进行声传播模拟计算的方法,根据相应的声速剖面及声传播损失,分析台风对声传播特性的影响。结果显示,2010年第10号台风"莫兰蒂"过境时,海洋环境对台风的响应较为迅速,海洋表层的温度和盐度变化剧烈,而声速及传播损失的变化较温度盐度缓慢。分析表明:台风过境会导致表面声速减小,深海声道最小声速增大,声传播损失增大,深海声道原第一会聚区位置最小声能损失增大5 d B,台风过境导致声线第一反折点位置下移,第一会聚区消失,使声传播距离缩短。展开更多
基金This work was supported by the Climate Research Branch of Environment Canada (Grant No. KM040-0-2233)the Chinese Academy of Sciences (Grant Nos. KZCX2-SW-118 and KZCX2-108).
文摘Reconstructions of past climate based on pollen data have formed a robust approach and produced a great of products in time scales from a millennium to ten millenniums. However, it is an attempt for reconstruction of the past decade-century climate in the Global Change field. This note reports a reconstruction of the past 1000-a temperature in a 50-a scale in Canada based on pollen data. Because there were little human activities during the last 1000 years in North America, the climate in the period mainly responded to natural changes. The reconstruction of a natural-forcing change in the climate can provide a basis to recognize the climate changes impacted from human activities in China. The technique of modern analogue can be implemented to reconstruct the past millennium climate in China.
文摘利用吕宋海峡附近海区温盐数据的数值模型进行声传播模拟计算的方法,根据相应的声速剖面及声传播损失,分析台风对声传播特性的影响。结果显示,2010年第10号台风"莫兰蒂"过境时,海洋环境对台风的响应较为迅速,海洋表层的温度和盐度变化剧烈,而声速及传播损失的变化较温度盐度缓慢。分析表明:台风过境会导致表面声速减小,深海声道最小声速增大,声传播损失增大,深海声道原第一会聚区位置最小声能损失增大5 d B,台风过境导致声线第一反折点位置下移,第一会聚区消失,使声传播距离缩短。
