College of Management, Shenzhen University, Nanhai Ave. 3688, Shenzhen, 518060, China.
Guy Carpenter Asia-Pacific Climate Impact Centre, School of Energy and Environment, City University of Hong Kong, Kowloon, Hong Kong, SAR.
Sci Rep. 2021 Mar 25;11(1):6935. doi: 10.1038/s41598-021-86412-x.
Spatial-temporal rainfall assessments are integral to climate/hydrological modeling, agricultural studies, and water resource planning and management. Herein, we evaluate spatial-temporal rainfall trends and patterns in Pakistan for 1961-2020 using nationwide data from 82 rainfall stations. To assess optimal spatial distribution and rainfall characterization, twenty-seven interpolation techniques from geo-statistical and deterministic categories were systematically compared, revealing that the empirical Bayesian kriging regression prediction (EBKRP) technique was best. Hence, EBKRP was used to produce and utilize the first normal annual rainfall map of Pakistan for evaluating spatial rainfall patterns. While the largest under-prediction was estimated for Hunza (- 51%), the highest and lowest rainfalls were estimated for Malam Jaba in Khyber Pakhtunkhwa province (~ 1700 mm), and Nok-kundi in Balochistan province (~ 50 mm), respectively. A gradual south-to-north increase in rainfall was spatially evident with an areal average of 455 mm, while long-term temporal rainfall evaluation showed a statistically significant (p = 0.05) downward trend for Sindh province. Additionally, downward inter-decadal regime shifts were detected for the Punjab and Sindh provinces (90% confidence). These results are expected to help inform environmental planning in Pakistan; moreover, the rainfall data produced using the optimal method has further implications in several aforementioned fields.
时空降雨评估是气候/水文模型、农业研究以及水资源规划和管理的重要组成部分。在此，我们使用来自 82 个雨量站的全国性数据，评估了 1961 年至 2020 年期间巴基斯坦的时空降雨趋势和模式。为了评估最佳的空间分布和降雨特征，我们系统地比较了来自地统计和确定性两类的 27 种插值技术，结果表明经验贝叶斯克里金回归预测 (EBKRP) 技术是最佳的。因此，我们使用 EBKRP 生成和利用了巴基斯坦首个正常年降雨量图，以评估空间降雨模式。虽然对 Hunza 的预测值低估最大（为 -51%），但对 Malam Jaba 在开伯尔-普赫图赫瓦省（约 1700 毫米）和 Nok-kundi 在俾路支省（约 50 毫米）的降雨量估计值最高和最低。降雨从南到北逐渐增加，面积平均值为 455 毫米，而长期的时间降雨评估显示，信德省的降雨呈统计上显著（p=0.05）的下降趋势。此外，旁遮普省和信德省的年代际下降转折也被检测到（置信度为 90%）。这些结果有望帮助指导巴基斯坦的环境规划；此外，使用最优方法生成的降雨数据在上述几个领域也有进一步的应用。
