Dyosi Masonwabe, Kalumba A M, Magagula H B, Zhou L, Orimoloye Israel R
Department of Geography and Environmental Science, Eastern Cape Province, University of Fort Hare, Private Bag X1314, Alice, 5700, South Africa.
Risk & Vulnerability Science Centre, University of Fort Hare, Alice Campus, South Africa.
Environ Monit Assess. 2021 May 28;193(6):365. doi: 10.1007/s10661-021-09126-7.
The world including South Africa is faced with unprecedented environmental changes, which can be linked to climate-related disasters such as drought and extreme heat. Several studies have indicated that these changes are likely to accelerate in the future and cause an adverse impact on the environment. The Eastern Cape Province of South Africa, especially Amathole District Municipality (ADM), has recorded a high number of climate change-related disasters including prolonged drought conditions witnessed during the winter season of 2008, 2009, 2014 and 2015 among others. Consequently, this study aimed at exploring remote sensing information to assess and document drought occurrences in the ADM from 2007 to 2017. To accomplish the aim, the Normalized Difference Vegetation Index, Land Surface Temperature and Precipitation were utilised to access drought spatiotemporal variations. For the analysis, a total of 396 satellite imageries (MODIS and TRMM) were used. The results revealed that different correlations exist between the three variables. The significance of correlations differed from one season to another. Furthermore, it was revealed that the drought conditions in the district differed in the spatial distribution. The study accurately identified the drought episodes that occurred in the ADM in the years 2008, 2009, 2014, 2015 and 2016. The chosen methodology and variables proved to be suitable for analysing drought conditions offering space and temporal variation dimension, which is vital in monitoring drought events.
包括南非在内的世界正面临前所未有的环境变化，这些变化可能与干旱和酷热等与气候相关的灾害有关。多项研究表明，这些变化未来可能会加速，并对环境造成不利影响。南非东开普省，特别是阿马托勒区市（ADM），记录了大量与气候变化相关的灾害，包括2008年、2009年、2014年和2015年冬季出现的长期干旱等情况。因此，本研究旨在探索遥感信息，以评估和记录2007年至2017年期间ADM的干旱发生情况。为实现这一目标，利用归一化植被指数、地表温度和降水量来获取干旱的时空变化。分析时总共使用了396幅卫星图像（MODIS和TRMM）。结果表明，这三个变量之间存在不同的相关性。相关性的显著性因季节而异。此外，研究还表明该地区的干旱状况在空间分布上存在差异。该研究准确识别了2008年、2009年、2014年、2015年和2016年ADM发生的干旱事件。所选用的方法和变量被证明适用于分析干旱状况，提供了空间和时间变化维度，这对监测干旱事件至关重要。
