Scholarlink

<p>Belg is the primary rainy season in southern Ethiopia and the secondary rainy season in the remaining regions. The major water supply for Belg is from the Southwest Indian Ocean, leading to the strong rainfall over southwestern and southern Ethiopia. This study investigates the spatiotemporal variability of Belg over the common period 1985–2023 across Ethiopia. The first and second typical anomalous modes of Belg account for 41.9% and 17.2% of the total rainfall variance, respectively. The first mode exhibits spatially coherent positive rainfall anomalies with maximum anomalies displaced eastward relative to the climatological rainfall centers. It is supported by the weakening of southeasterly moisture advection from the Indian Ocean and the enhanced humidity most pronounced over central and eastern Ethiopia. The strong divergence at the upper troposphere also favors stronger convections, leading to heavier rainfall. The second mode features a dipole pattern with lower-than-normal rainfall in the northwest and higher-than-normal rainfall in the south, which are mainly attributed to the intensified cold-dry northwesterly from the Sahara Desert and the topographic blocking of the central highlands. The interannual variability of the first mode has intensified since the 2010s with statistically significant 2-4-year oscillation after 2020. The Pacific Meridional Mode (PMM) in the previous autumn is highly correlated with the first mode. The PMM is therefore suggested to be a potential monitoring index for Belg prediction, which will benefit agricultural planning, water-resource management, and disaster preparedness in Ethiopia.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Leading modes of Belg rainfall variability in Ethiopia

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年4月24日

查看全文
  • Leta Bekele Gudina,
  • Jie Zhang,
  • Yixiong Lu,
  • Xiaoge Xin,
  • Tongwen Wu,
  • Asaminew Teshome Game,
  • Xindan Zhang,
  • Mulualem Abera Waza,
  • Couhua Liu

摘要

Belg is the primary rainy season in southern Ethiopia and the secondary rainy season in the remaining regions. The major water supply for Belg is from the Southwest Indian Ocean, leading to the strong rainfall over southwestern and southern Ethiopia. This study investigates the spatiotemporal variability of Belg over the common period 1985–2023 across Ethiopia. The first and second typical anomalous modes of Belg account for 41.9% and 17.2% of the total rainfall variance, respectively. The first mode exhibits spatially coherent positive rainfall anomalies with maximum anomalies displaced eastward relative to the climatological rainfall centers. It is supported by the weakening of southeasterly moisture advection from the Indian Ocean and the enhanced humidity most pronounced over central and eastern Ethiopia. The strong divergence at the upper troposphere also favors stronger convections, leading to heavier rainfall. The second mode features a dipole pattern with lower-than-normal rainfall in the northwest and higher-than-normal rainfall in the south, which are mainly attributed to the intensified cold-dry northwesterly from the Sahara Desert and the topographic blocking of the central highlands. The interannual variability of the first mode has intensified since the 2010s with statistically significant 2-4-year oscillation after 2020. The Pacific Meridional Mode (PMM) in the previous autumn is highly correlated with the first mode. The PMM is therefore suggested to be a potential monitoring index for Belg prediction, which will benefit agricultural planning, water-resource management, and disaster preparedness in Ethiopia.