Ximeng Xu

Dr. Ximeng Xu

Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
orcid

Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 June 2020 in Earth's Future
Verified
Journal Article
Open access
PDF file
GHGebremedhin Gebremeskel Gebremeskel Haile
Gebremedhin Gebremeskel Gebremeskel Haile
Qiuhong TangQiuhong Tang
Qiuhong Tang
SHSeyed-Mohammad Hosseini-Moghari
Seyed-Mohammad Hosseini-Moghari
Xingcai LiuXingcai Liu
Xingcai Liu
TGTesfay Gebremicael
Tesfay Gebremicael
XYXiaobo Yun
Xiaobo Yun
Investigation of the pressing impacts of climate change on drought is vital for sustainable societal and ecosystem functioning. The magnitude of how much the drought will change and the way how droughts would affect society and the environment are inadequately addressed over East Africa. This study aimed at assessing future drought changes using an ensemble of five Global Climate Models (GCMs) in the Coupled Model Intercomparison Project (CMIP5) over East Africa. To this end, drought characteristics were investigated under the Representative Concentration Pathways (RCPs) 2.6, 4.5 and 8.5 in the near‐term (the 2020s; 2011–2040), mid‐century (2050s; 2041–2070), and end‐of‐century (2080s; 2071–2100). The changes of the Standardized Precipitation Index (SPI) and Standardized Precipitation‐Evapotranspiration Index (SPEI) were first compared, and the SPEI was used for measuring future droughts as it showed stronger changes due to its inclusion of temperature effects. Drought area in East Africa is likely to increase at the end of the 21st century by 16%, 36% and 54% under RCP 2.6, 4.5 and 8.5, respectively, with the areas affected by extreme drought increasing more rapidly than severe and moderate droughts. Spatially, drought event, duration, frequency and intensity would increase in Sudan, Tanzania, Somalia, South Sudan, but generally decrease in Kenya, Uganda and Ethiopian highlands. Results also confirm that drought changes over East Africa follow the “dry gets drier and wet gets wetter” paradigm. The findings provide important guidance for improving identification of causes, minimizing the impacts and enhancing the resilience to droughts in East Africa.

1 April 2018 in Soil and Tillage Research
Verified
Journal Article
Closed access
XXXimeng Xu
Ximeng Xu
FZFenli Zheng
Fenli Zheng
GWG.V. Wilson
G.V. Wilson
CHChao He
Chao He
JLJia Lu
Jia Lu
FBFeng Bian
Feng Bian

3 November 2017 in Land Degradation & Development
Verified
Journal Article
Closed access
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XXXimeng Xu
Ximeng Xu
FZFen-li Zheng
Fen-li Zheng
GWGlenn V. Wilson
Glenn V. Wilson
MWMin Wu
Min Wu

5 February 2018 in Earth Surface Processes and Landforms
Verified
Journal Article
Closed access
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HWHongyan Wu
Hongyan Wu
XXXimeng Xu
Ximeng Xu
FZFen-li Zheng
Fen-li Zheng
CQChao Qin
Chao Qin
XHXu He
Xu He

1 January 2021 in Ecological Engineering
Verified
Journal Article
Closed access
YZYuanyuan Zhou
Yuanyuan Zhou
DFDongjie Fu
Dongjie Fu
CLChunxia Lu
Chunxia Lu
XXXimeng Xu
Ximeng Xu
Qiuhong TangQiuhong Tang
Qiuhong Tang

21 January 2019 in Sensors
Verified
Journal Article
Open access
PDF file
BBBinod Baniya
Binod Baniya
Qiuhong TangQiuhong Tang
Qiuhong Tang
XXXimeng Xu
Ximeng Xu
GHGebremedhin Gebremeskel Gebremeskel Haile
Gebremedhin Gebremeskel Gebremeskel Haile
Gyan Chhipi ShresthaGyan Chhipi Shrestha
Gyan Chhipi Shrestha
Identification of drought is essential for many environmental and agricultural applications. To further understand drought, this study presented spatial and temporal variations of drought based on satellite derived Vegetation Condition Index (VCI) on annual (Jan–Dec), seasonal monsoon (Jun–Nov) and pre-monsoon (Mar–May) scales from 1982–2015 in Nepal. The Vegetation Condition Index (VCI) obtained from NOAA, AVHRR (National Oceanic and Atmospheric Administration, Advanced Very High Resolution Radiometer) and climate data from meteorological stations were used. VCI was used to grade the drought, and the Mann–Kendall test and linear trend analysis were conducted to examine drought trends and the Pearson correlation between VCI and climatic factors (i.e., temperature and precipitation) was also acquired. The results identified that severe drought was identified in 1982, 1984, 1985 and 2000 on all time scales. However, VCI has increased at the rate of 1.14 yr−1 (p = 0.04), 1.31 yr−1 (p = 0.03) and 0.77 yr−1 (p = 0.77) on the annual, seasonal monsoon and pre-monsoon scales, respectively. These increased VCIs indicated decreases in drought. However, spatially, increased trends of drought were also found in some regions in Nepal. For instance, northern areas mainly in the Trans-Himalayan regions identified severe drought. The foothills and the lowlands of Terai (southern Nepal) experienced normal VCI, i.e., no drought. Similarly, the Anomaly Vegetation Condition Index (AVCI) was mostly negative before 2000 which indicated deficient soil moisture. The exceedance probability analysis results on the annual time scale showed that there was a 20% chance of occurring severe drought (VCI ≤ 35%) and a 35% chance of occurring normal drought (35% ≤ VCI ≤ 50%) in Nepal. Drought was also linked with climates in which temperature on the annual and seasonal monsoon scales was significant and positively correlated with VCI. Drought occurrence and trends in Nepal need to be further studied for comprehensive information and understanding.