We investigate how climate change may impact the winter cloud seeding opportunity in the western U.S. focusing on Utah mountains. To do this, we utilize the high-resolution Weather Research and Forecasting regional climate model data that was simulated by the National Center for Atmospheric Research (NCAR).
Future plan of winter orographic cloud seeding is critical to enhancing snowfall over the mountains since several states in the western U.S. conduct cloud seeding operation. This study helps to make a better plan for the cloud seeding program with how future warming may impact the seeding condition during different months. There will be less seeding opportunity and/or may not be suitable for seeding some of the mountains in southern Utah in some months of winter.
Assessment of how the wintertime cloud seeding conditions over Utah’s mountains may change provides essential information for the state to work on increasing its snowpack in the warmer climate. This is the first study that explores the impact of future climate change on cloud seeding conditions. Based on two atmospheric variables commonly used in cloud-seeding operations, i.e. average temperature from the surface to 1 km above ground level (-20°C T -6°C) and vertically integrated supercooled liquid water (SLW > 0.01 mm), Utah’s mountains are suitable for seeding more than 20% of the time during winter. A greater rate of suitability exists in the northern and Uinta Mountains. In the warmer climate under a high-emissions scenario, these seeding conditions may wane as the percentage of precipitating clouds suitable for seeding, about 60% under current conditions, would decline to about 40% across the state with significance. This projected decrease is due to rising temperatures and a decreased frequency of precipitation events. These findings imply that climate warming will narrow the window of opportunity for winter cloud seeding operations in Utah.