南方夏秋干旱期间的天气气候特征

对40多年来南方的天气气候特征进行了分析,提出了7～9月夏秋干旱期形成干旱的主要天气系统为西太平洋副热带高压.从干燥度和降水的空间分布综合分析,得出了南方最旱区位于湖南、江西中部.广西、贵州、湖南西北和东南山区、江西南部山区、安徽南部山区、福建-浙江沿海交界山区和苏北沿海为湿润区,人工增雨潜力较大.特殊地形所形成的焚风效应是形成湘中干旱不可忽略的原因.为南方夏秋期间对流云降水潜力研究和科学实施人工增雨作业提供一定依据.     

短期气候预测的现状 问题与出路(一)

从方法论上分析了短期气候预测的现状、问题与出路。着重指出：基础理论研究的欠缺又不甚得法是短期气候预测准确率提高缓慢的原因；应当将数值预报的提法从初值问题改为演变问题，进一步提为反问题；统计学方法与动力学方法要相互借鉴，取长补短，融合发展。     

北京猿人洞穴堆积气候地层的重新划分与对比

周口店第一地点洞穴四十余米厚的堆积层自下而上共分为 17层 ,新近测量的年代推前了近 2 0 0 ka。对堆积层所含哺乳动物化石和孢粉资料进行聚类统计和因子分析 ,结合风化系数和微量元素含量等古气候代用指标 ,重新定量地描绘它所记录的古气候波动旋回。根据第 2层 TIMS测年为 410 ka B.P.,第 14层上部是磁性地层测量的B/ M界线 ,可以将该洞穴堆积层 1— 14层对比于深海岩心 δ1 8O气候曲线的 11— 19段或中国黄土—古土壤序列S4— S7,并且古气候旋回内的次级波动也可进行一定程度的对比。     

青藏高原东北部贵德盆地上新世沉积环境分析及其意义

青海贵德盆地发育巨厚的新生代地层,在青藏高原北部具有很好的代表性,其中含较丰富的重要哺乳动物化石,对确定盆地及周边相似地层的年代、高原隆升过程具有重要的科学意义.结合哺乳动物采用典型剖面精确古地磁测年为基础的时间框架,通过盆地沉积层序、沉积相和沉积演化以及其对构造和气候变化响应的研究表明:6.5～约1.8MaB.P.期间盆地沉积环境变化经历了8个阶段的演化,反映在此期间青藏高原北部经历了＞5.4MaB.P.、3.6MaB.P.、2.6MaB.P.和1.8MaB.P.4次明显的构造挤压隆升运动,其中约1.8MaB.P.的构造运动可能使黄河向上游溯源侵蚀,同时切穿积石峡、李家峡和松巴峡而到达贵德盆地.研究时段内气候以干旱为主,但在6.2～4MaB.P.和2.1～1.85MaB.P.的两个时期气候明显湿润.     

The effect of Holocene temperature fluctuations on the evolution and ecology of Neotoma (woodrats) in Idaho and northwestern Utah

Animals respond to climatic change by adapting or by altering distributional patterns. How an animal responds is influenced by where it is positioned within its geographic range; the probability of extirpation is increased near range boundaries. Here, we examine the impact of Holocene climatic fluctuations on a small mammalian herbivore, the bushy-tailed woodrat (Neotoma cinerea), at five locations within south central Idaho and northwestern Utah. Previous work demonstrated that woodrats adapt to temperature shifts by altering body size. We focus here on the relationship between body mass, temperature, and location within the geographic range. Body mass is estimated by measuring fossil fecal pellets, a technique validated in earlier work. Overall, we find the predicted phenotypic response to climate change: animals were larger during cold periods, and smaller during warmer episodes. However, we also identify several time periods when changes in environmental temperature exceeded the adaptive flexibility of N. cinerea. A smaller-bodied species, the desert woodrat (N. lepida) apparently invaded lower elevation sites during the mid-Holocene, despite being behaviorally and physically subordinate to N. cinerea. Analysis of contemporary patterns of body size and thermal tolerances for both woodrat species suggests this was because of the greater heat tolerance of N. lepida. The robust spatial relationship between contemporary body size and ambient temperature is used as a proxy to reconstruct local climate during the Holocene.     

象头山自然保护区的气候特征

象头山自然保护区地处南亚热带湿润季风气候区，具有热量丰富、降水充沛、室气湿润、湿季长、干季短、植物生长期长、风向随季节改变、气候垂直变化大等特点，有大风、台风和雷暴危害。     

Linkage of liquid conductivity of glacier ice with its alkalinity over the north Qinghai-Xizang (Tibet) Plateau

Liquid conductivity (EC) measurement was conducted for the samples collected from several snow pits and ice cores over the Qinghai-Xizang (Tibet) Plateau, with their time range covering seasonal, decadal and centennial scales. Unlike the previous attention mostly focused on the acidity (H⁺) responding to the solid conductance (ECM) of glacial ice, we introduce the alkalinity (OH⁻) of snow and ice to show how it responds to EC. Strong linear relationship was established between EC and OH⁻ for these snow pits and ice cores. Positive correlation is also established between EC and major cations (Ca²⁺, Mg²⁺, Na⁺ and K⁺). Since the cations are known as the proxies for the intensity of mineral dust influx onto glaciers of the northern Qinghai-Xizang Plateau, we believe that EC could be used as an indicator for the history of dust input in deep ice core study. In fact, records in Guliya ice core since the Little Ice Age (LIA) indicate that dust load in glacier may depend on the combination of temperature and humidity. “Cold-dry” combination favors the dust arising, and results in higher EC and OH⁻ values, while “warm-wet” combination prevents dust form and EC and OH⁻ values are lower. In the past century, with the atmospheric warming and precipitation increasing over the northern plateau, which means an atmospheric condition of dust decreasing, both EC and OH⁻ displayed rapid decline.     

Linkage of liquid conductivity of glacier ice with its alkalinity over the north Qinghai-Xizang (Tibet) Plateau--Implication to the past dust recovery

Liquid conductivity (EC) measurement was conducted for the samples collected from several snow pits and ice cores over the Qinghai-Xizang (Tibet) Plateau, with their time range covering seasonal, decadal and centennial scales. Unlike the previous attention mostly focused on the acidity (H+) responding to the solid conductance (ECM) of glacial ice, we introduce the alkalinity (OH?) of snow and ice to show how it responds to EC. Strong linear relationship was established between EC and OH? for these snow pits and ice cores. Positive correlation is also established between EC and major cations (Ca2+, Mg2+, Na+ and K+). Since the cations are known as the proxies for the intensity of mineral dust influx onto glaciers of the northern Qinghai-Xizang Plateau, we believe that EC could be used as an indicator for the history of dust input in deep ice core study. In fact, records in Guliya ice core since the Little Ice Age (LIA) indicate that dust load in glacier may depend on the combination of temperature and humidity. "Cold-dry" combination favors the dust arising, and results in higher EC and OH- values, while "warm-wet" combination prevents dust form and EC and OH- values are lower. In the past century, with the atmospheric warming and precipitation increasing over the northern plateau, which means an atmospheric condition of dust decreasing, both EC and OH- displayed rapid decline.     

青藏高原腹地湖泊沉积纪录的“仙女木期”古气候颤动事件

通过对青藏高原腹地钻孔岩心剖面的最新研究,用层序地层学与年代地层学和气候地层学相结合的方法,分辨出可可西里地区苟弄措湖泊沉积记录(孔深7.25 m)约30 ka BP以来的古气候变化,并在孔深3.32～1.98 m处识别出“仙女本期”的3个气候颤动事件,即:①老仙女术事件(孔深3.32～2.62 m);②中仙女本事件(孔深2.62～2.43 m);③新仙女本事件(孔深2.43～1.98 m)。这3个气候颤动事件都是以冷干时段开始、以冷湿时段结束的,并有越向后期其冷干的时段越长的变化趋势,而其后的冷湿时段却具有等时的变化趋势。岩心沉积物的有机碳、有机氮和磁化率以及化学元素含量的变化,都与仙女本期气候变化具有十分吻合的变化态势。仙女术期气候在湖泊沉积物中的响应,在青藏高原环境演化中还是首次发现,为研究第四纪末次冰期冰消期以来的气候变化提供了新的信息。     

晚更新世东亚季风气候不稳定性的洞穴石笋同位素证据

据南京汤山葫芦洞石笋的23个热电离质谱测年结果和分辨率达100-200a的氧、碳稳定同位素测试数据，讨论了75-35kaBP期间东亚季风气候的高频振荡特征。石笋氧同位素值的波动范围介于-9.165‰～5.456‰之间，相邻峰谷的变幅可达2‰～3‰，由其构成的16个气候不稳定性事件与格陵兰冰心δ^18o记录中IS8-IS20和北大西洋冰漂碎屑事件H4-H6有良好的对比关系，揭示了东亚季风气候变化与高纬极地大气温度变化存在着动力机制上的联系。石笋碳同位素记录呈现类似于δ^18O记录的高频振荡形式，反映了洞穴了覆植被类型对存在着动力机制上的联系。石笋碳同位素记录呈现类似于δ^18O记录的高频振荡形式，反映了洞穴上覆植被类型对气候变化的快速响应。石笋稳定同位素曲线上72ka BP左右的快速降温事件与印度尼西亚Toba火山喷发事件基本一致。有可能说明是更新世全球气候事件的发生并非单一源于北大西洋深层水体的变化。