...
首页> 外文期刊>Theoretical and applied climatology >Interdecadal variability and trends of rainfall across the Amazon basin
【24h】

Interdecadal variability and trends of rainfall across the Amazon basin

机译:整个亚马逊河流域年代际变化和降雨趋势

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       

摘要

An analysis of decadal and long-term patterns of rainfall has been carried out using a combination of raingauge and gridded rainfall datasets, for the entire Amazon basin and for its northern and southern sub-basins. The study covers the period 1929-98. Rainfall variability and variations in circulation and sea surface temperature fields have been analysed in more detail for the period 1950-98. Negative rainfall trends were identified for the entire Amazon basin, while at the regional level there is a negative trend in northern Amazonia and positive trend in southern Amazonia. Decadal time scale variations in rainfall have been discovered, with periods of relatively drier and wetter conditions, with different behaviour in northern and southern Amazonia. Spectral analyses show decadal time scale variations in southern Amazonia, while northern Amazonia exhibits both interannual and decadal scale variations. Shifts in the rainfall regime in both sections of the Amazon basin were identified as occurring in the mid-1940s and 1970s. After 1975-76, northern Amazonia received less rainfall than before 1975. Changes in the circulation and oceanic fields after 1975 suggest an important role of the warming of the tropical central and eastern Pacific on the decreasing rainfall in northern Amazonia, due to more frequent and intense El Nino events during the relatively dry period 1975-98.
机译:对于整个亚马逊流域及其北部和南部子流域,已经使用雨量计和栅格化的降雨数据集进行了十年和长期降雨模式的分析。研究涵盖了1929-98年。在1950-98年期间,对降雨的变化性以及环流和海表温度场的变化进行了更详细的分析。在整个亚马逊流域,降雨趋势被确定为负值,而在区域一级,北部亚马逊地区则为负趋势,而南部亚马逊地区则为正趋势。已经发现降雨的年代际时间尺度变化,条件是相对干燥和潮湿的时期,亚马逊河北部和南部的行为不同。频谱分析显示,南部亚马逊地区的年代际时间尺度变化,而北部亚马逊地区则同时显示年际和年代际尺度变化。亚马逊流域两个地区的降雨方式都被确定为发生在1940年代中期和1970年代中期。 1975-76年之后,北部亚马逊地区的降雨少于1975年之前。1975年之后,环流和海洋领域的变化表明,热带中部和东部太平洋变暖对北部亚马逊地区降雨的减少具有重要作用,这是由于更频繁和更频繁地发生的。在相对干旱的1975-98年期间发生了强烈的厄尔尼诺现象。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号