一个14000年的氧同位素记录来自藻石在山上的两个高山湖. 肯尼亚 肯尼亚 肯尼亚 肯尼亚
P A Barker1, F A Street-Perrott, M J Leng
1Department of Geography, Lancaster University, Lancaster LA1 4YB, UK.
Science (New York, N.Y.)
|June 26, 2001
概括
热带地区的气候变化可以使用氧同位素来追踪. 蒙特利尔山 (Mt. Mt. Mt. Mt. Mt. Mt. Mt. Mt. Mt. 肯尼亚 肯尼亚 肯尼亚 肯尼亚
科学领域:
- 古气候学 古气候学
- 同位素地球化学 同位素地球化学
- 热带气候研究 热带气候研究
背景情况:
- 在藻石灰中的氧同位素是热带地区敏感的气候指标.
- 解释热带山地同位素记录是复杂的,有关于降水与温度影响的辩论.
- 来自山上的14,000年的记录. 肯尼亚的高山湖泊显示出显著的氧同位素转移.
研究的目的:
- 为了调查Holocene氧同位素变异的驱动因素 (δ18O) 在Mt. 肯尼亚高山湖沉积物. 肯尼亚高山湖沉积物.
- 为了澄清降水和温度在热带山地气候重建中的作用.
- 为了将古气候变化与山上的环境变化联系起来. 肯尼亚. 肯尼亚.
主要方法:
- 从两个阿尔卑斯山湖沉积物核心中,在藻石灰中分析氧同位素比率 (δ18O).
- 沉积物层的约会,以建立一个14000年的气候记录.
- 同位素数据与古气候事件和环境指标的相关性.
主要成果:
- 在14000年间,在藻 δ18O中观察到高达18‰的突然变化.
- 全新世 δ18O 变化更好地通过湖泊水分平衡的变化而不是温度来解释.
- 确定了与侵蚀,冰川和森林扩张相关的大量对流降雨的不同时期.
结论:
- 湖水平衡,而不是温度,是这个热带山地环境中Holocene δ18O变化的主要驱动因素.
- 过去的暴雨事件对山脉产生了重大影响. 肯尼亚的环境,包括土壤侵蚀和冰川活动.
- 氧同位素记录为过去的热带气候动态及其生态后果提供了宝贵的见解.
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