Department of Atmospheric and Oceanic Sciences, University of Colorado Boulder, Boulder, CO 80309;
Research Applications Laboratory, National Center for Atmospheric Research, Boulder, CO 80307.
Proc Natl Acad Sci U S A. 2020 Mar 10;117(10):5190-5195. doi: 10.1073/pnas.1917204117. Epub 2020 Feb 24.
Climate change and population growth have increased demand for water in arid regions. For over half a century, cloud seeding has been evaluated as a technology to increase water supply; statistical approaches have compared seeded to nonseeded events through precipitation gauge analyses. Here, a physically based approach to quantify snowfall from cloud seeding in mountain cloud systems is presented. Areas of precipitation unambiguously attributed to cloud seeding are isolated from natural precipitation (<1 mm h). Spatial and temporal evolution of precipitation generated by cloud seeding is then quantified using radar observations and snow gauge measurements. This study uses the approach of combining radar technology and precipitation gauge measurements to quantify the spatial and temporal evolution of snowfall generated from glaciogenic cloud seeding of winter mountain cloud systems and its spatial and temporal evolution. The results represent a critical step toward quantifying cloud seeding impact. For the cases presented, precipitation gauges measured increases between 0.05 and 0.3 mm as precipitation generated by cloud seeding passed over the instruments. The total amount of water generated by cloud seeding ranged from 1.2 × 10 m (100 ac ft) for 20 min of cloud seeding, 2.4 × 10 m (196 ac ft) for 86 min of seeding to 3.4 x 10 m (275 ac ft) for 24 min of cloud seeding.
气候变化和人口增长增加了干旱地区对水的需求。半个多世纪以来，人们一直在评估人工增雨技术来增加水资源供应；统计方法通过雨量计分析比较了播种和非播种事件。在这里，提出了一种基于物理的方法来量化山区云系中云种的降雪量。从自然降水（<1 毫米/小时）中明确归因于云种的降水区域被隔离出来。然后使用雷达观测和雪量计测量来量化播种引起的降水的时空演变。本研究采用结合雷达技术和雨量计测量的方法，量化了冬季山区云系的冰成云种对降雪的时空演变及其时空演变。这些结果代表了量化人工增雨影响的关键一步。对于所提出的情况，当云种产生的降水经过仪器时，雨量计测量到的降水量增加了 0.05 到 0.3 毫米之间。云种产生的总水量范围从 20 分钟的云种产生的 1.2×10 立方米（100 英亩英尺）到 86 分钟的云种产生的 2.4×10 立方米（196 英亩英尺），再到 24 分钟的云种产生的 3.4×10 立方米（275 英亩英尺）。
