## 3 Results  
### Localized Climate Change  
To better analyze the meteorological changes in the ten regions, we calculated the difference in meteorological elements between two distinct periods (Table 3). Compared to the period before the construction of the reservoir, climate change is primarily characterized by increases in both precipitation and temperature after the reservoir's construction. Annual precipitation in the region is unevenly distributed, with concentration during the summer months (Figure 3). After construction, both average temperature and precipitation showed increases on an annual scale (P range 3-10%, e.g., 0.3 \({}^{\circ}\)C/10a in LJ and 41.26 mm/10a in JS). In terms of seasonal variations, both temperature (T) and precipitation (P) increased across all seasons, except for a decrease in mean temperature during winter, with the most noticeable changes occurring in spring and fall (Figure 3). The largest temperature increase occurred in spring at LJ (0.51 \({}^{\circ}\)C/10a) and in fall at JS (0.38 \({}^{\circ}\)C/10a). Despite an overall trend of increasing precipitation, some areas experienced a decrease in spring and summer (three regions showing declining precipitation), while winter precipitation generally remained negative, though with less variability. Regarding the rate of temperature change, summer trends remained consistent with pre-construction patterns (observed in 7 out of 10 reservoirs), with relatively small temperature changes following construction, the maximum rate being 0.7 \({}^{\circ}\)C/10a. Notably, winter temperature changes showed the largest differences between reservoirs after construction, with some reservoirs reversing their temperature trends. For instance, the temperature at LJ dropped by \(-\)2.4 \({}^{\circ}\)C/10a before construction but increased by 1.0 \({}^{\circ}\)C/10a after construction, resulting in a 3.4 \({}^{\circ}\)C/10a  
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multicolumn{1}{c}{**Differences in Climate Elements Across Reservoirs (10a After Impoundment—10a Before Impoundment)**} & & & & & & & & & & \\ \hline \multicolumn{1}{c}{**Climate**} & **Time** & **LX** & **NN** & **LJ** & **ZG** & **KY** & **GB** & **SZ** & **HF** & **JS** & **SG** \\ \hline \multirow{4}{*}{Temperature} & Spring & 0.12 & 0.19 & 0.51 & 0.31 & 0.20 & 0.28 & 0.29 & 0.12 & 0.12 & 0.11 \\  & Summer & 0.19 & 0.30 & 0.44 & 0.17 & 0.09 & 0.19 & 0.17 & 0.13 & 0.30 & 0.25 \\  & Fall  
change (Table 3). Temperature changes were steeper in the annual and fall periods and smaller in winter. Precipitation changes were more complex and exhibited clear regional differences. A gradual decline compared to the previous period suggests that the reservoir had a more pronounced impact on local precipitation patterns. The negative slope of precipitation change in the LJ and KY reservoirs indicates alterations in local precipitation distribution, affecting its spatial patterns (Figure 3). Following construction, autumn precipitation increased, while spring and summer saw decreases in certain areas. Winter precipitation  
Figure 3: Climate change trend chart (x-axis reservoirs 1–10 represent LX–S], y-axis time series \(-\)10–10 represent before and after construction). tion exhibited minimal variation, with most areas showing lower rates of change. The most significant rate of change occurred in summer, with the GB reservoir experiencing a 6.89 mm/decade increase, and the smallest occurred in winter, with the ZG reservoir showing a 0.22 mm/decade decrease (Table 3). Overall, summer precipitation in the reservoir area generally increased by 5-15%, whereas winter precipitation changes were minimal, typically within \(\pm\)3%. Following reservoir construction, the temporal precipitation trend exhibited an enhanced increase in summer, while winter precipitation trends remained relatively stable. At certain hydropower stations, precipitation slopes showed an increasing trend across all seasons, indicating the gradual emergence of local climate effects after reservoir impoundment.