The impact of climate change and human activities on streamflow and sediment load in the Pearl River basin

Considerable biases in precipitation simulations in climate models have required the adoption of delta-change approaches to construct future precipitation scenarios for hydrological climate change impact studies. However, different delta-change methods yield different future precipitation scenarios that might significantly affect the projected future streamflow. To assess these effects, two delta-change methods were compared: the simple delta-change (SDC) method with a constant scaling factor and the quantile-quantile delta-change (QQDC) method with a quantile mapping-based non-uniform delta factor. The Xinanjiang (XAJ) hydrological model was applied using historical climatic data and two future precipitation scenarios for streamflow simulations in the Pearl River basin, China. The results show that the two delta-change methods have significant influences on future precipitation and streamflow projections, and these impacts become more distinct at finer and extreme event time scales. For instance, the QQDC method projects the 20-year daily maximum precipitation to be 8.1–98.6% higher than the SDC method. Consequently, the XAJ model with the QQDC future precipitation produces the 20-year daily maximum streamflow to be approximately 7.0–65.0% higher than that using the SDC precipitation. It implies that future precipitation transformation methods are a source of uncertainty, affecting future discharge projections. Such uncertainty should be considered in water resources management and flood control strategies for future climate change adaptations.

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Evaluation of drought occurrence and climate change in the Pearl River Basin in south China

10.5353/th_991021868309703414 ◽

2016 ◽

Author(s):

Yuchen Du

Keyword(s):

Climate Change ◽

River Basin ◽

South China ◽

Pearl River ◽

Pearl River Basin ◽

The Pearl River ◽

Drought Occurrence ◽

The Pearl River Basin

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Moisture Variability in the East Pearl River Basin since 1894 CE Inferred from Tree Ring Records

Atmosphere ◽

10.3390/atmos11101075 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1075

Author(s):

Teng Li ◽

Jinbao Li ◽

Tsun Fung Au ◽

David D. Zhang

Keyword(s):

Climate Change ◽

River Basin ◽

Tree Ring ◽

Climatic Research Unit ◽

Pearl River ◽

Spatial Correlations ◽

Pearl River Basin ◽

The Pearl River ◽

The Pearl River Basin ◽

Moisture Variability

Short-term climate change in South China has been extensively studied based on meteorological or hydrological records. However, tree ring-based long-term climate change research is rare, especially in the Pearl River basin, owing to the difficulty in finding old-aged trees. Here, we present a 200-year tree ring width chronology of Pinus kwangtungensis in the east Pearl River basin with reliable coverage from 1894 to 2014. Based on the significant climate-growth relationship between tree growth and annual self-calibrating Palmer drought severity index (scPDSI) from previous May to current April, the pMay-cApr scPDSI was reconstructed for the period 1894–2014. The reconstruction reveals four dry periods during 1899–1924, 1962–1974, 1988–1994, and 2003–2014, and four wet periods during 1894–1898, 1925–1961, 1975–1987, and 1995–2002. Significant spatial correlations between the reconstructed scPDSI and the Climatic Research Unit (CRU) gridded scPDSI indicate that our reconstruction can effectively represent regional moisture variability in the Pearl River basin. Spatial correlations with global sea surface temperatures (SSTs) show that our reconstruction is negatively correlated with northern and western Pacific SSTs while positively correlated with eastern Pacific SSTs, suggesting that SST variability in these domains strongly affects moisture change in the Pearl River basin.

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Spatiotemporal Variability of Actual Evapotranspiration and the Dominant Climatic Factors in the Pearl River Basin, China

Atmosphere ◽

10.3390/atmos10060340 ◽

2019 ◽

Vol 10 (6) ◽

pp. 340 ◽

Cited By ~ 2

Author(s):

Weizhi Gao ◽

Zhaoli Wang ◽

Guoru Huang

Keyword(s):

Climate Change ◽

River Basin ◽

Climatic Factors ◽

Actual Evapotranspiration ◽

Pearl River ◽

Pearl River Basin ◽

Sunshine Hours ◽

Increasing Trend ◽

The Pearl River ◽

The Pearl River Basin

Evapotranspiration is a vital component of the land surface process, thus, a more accurate estimate of evapotranspiration is of great significance to agricultural production, research on climate change, and other activities. In order to explore the spatiotemporal variation of evapotranspiration under global climate change in the Pearl River Basin (PRB), in China, this study conducted a simulation of actual evapotranspiration (ETa) during 1960–2014 based on the variable infiltration capacity (VIC) model with a high spatial resolution of 0.05°. The nonparametric Mann–Kendall (M–K) test and partial correlation analysis were used to examine the trends of ETa. The dominant climatic factors impacting on ETa were also examined. The results reveal that the annual ETa across the whole basin exhibited a slight but not significant increasing trend during the 1960–2014 period, whereas a significant decreasing trend was found during the 1960–1992 period. At the seasonal scale, the ETa showed a significant upward trend in summer and a significant downward trend in autumn. At the spatial scale, the ETa generally showed a decreasing, but not significant, trend in the middle and upper stream of the PRB, while in the downstream areas, especially in the Pearl River Delta and Dongjiang River Basin, it exhibited a significant increasing trend. The variation of the ETa was mainly associated with sunshine hours and average air pressure. The negative trend of the ETa in the PRB before 1992 may be due to the significant decrease in sunshine hours, while the increasing trend of the ETa after 1992 may be due to the recovery of sunshine hours and the significant decrease of air pressure. Additionally, we found that the “paradox” phenomenon detected by ETa mainly existed in the middle-upper area of the PRB during the period of 1960–1992.

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