Motivation
Recent China cloud seeding issues
Recent Weather Modification Methods
Objectives
Cloud seeding is a weather modification technique used to boost precipitation by helping clouds release more moisture. It’s mostly used in places that struggle with water shortages, especially during droughts. There are four main objectives of cloud seeding, each with its own role in addressing water and climate challenges.
The first objective is to increase precipitation. By encouraging clouds to produce more rain or snow, cloud seeding can help fill up reservoirs, lakes, and other water supplies. This extra precipitation is critical for regions that don’t get enough rainfall naturally, and it helps provide water for everyday use.
The second goal is to support agriculture. Farming relies heavily on rainfall, and in dry seasons or drought conditions, crops can suffer without enough water. Cloud seeding helps provide additional moisture, protecting crops and supporting food production by making sure plants have the water they need to grow.
A third objective is to alleviate drought. Long-term droughts can cause serious harm to both communities and the environment. By increasing rainfall in areas experiencing drought, cloud seeding can help restore water sources, improve soil moisture, and reduce the negative impacts that come with prolonged dry conditions.
Lastly, cloud seeding can help aid climate adaptation. Even though it’s not a direct solution to climate change, it can be a helpful tool in adapting to changing weather patterns. It provides valuable data for scientists studying precipitation management and gives regions another option for responding to extreme weather and water shortages caused by climate change.
Overall, the four main objectives of cloud seeding show how this technology can be used in different ways to meet growing water and climate challenges around the world. While research is still ongoing, cloud seeding offers exciting possibilities for creating more sustainable and resilient communities.
Problems
Potential Environmental Concerns of Silver Iodide
Silver iodide nuclei help form snowflakes in clouds by creating bases for water to condense on
One of the main cloud seeding materials is silver iodide (Agl), which takes up to 60-70% of the material for cloud seeding. While effective for cloud seeding, it can raise environmental concerns when used in large or repeated quantities. As silver is a heavy metal, and like other heavy metals, it can accumulate in soil and water over time. Although AgI is only slightly soluble, repeated seeding could increase silver levels in ecosystems, potentially impacting soil organisms, aquatic life, and plants.
In certain forms or concentrations, silver ions (Ag⁺) are toxic to fish and other aquatic organisms, even at relatively low levels. Long-term exposure could affect biodiversity in rivers, lakes, and wetlands. Another concern is that silver iodide is not biodegradable. It can remain in the environment for extended periods. It may accumulate in the food chain.
The amounts of AgI used in cloud seeding are relatively small compared to industrial silver pollution. However, frequent or large-scale use in the same area could change that risk profile over time. While current research suggests minimal immediate harm at typical seeding levels, long-term ecological effects are still not fully understood. Thus, we should be aware of such side effects and be cautious of using it.
Unexpected Weather Issues
Floods in Dubai
Storm in China
Experts related to testing these cloud seedings say that China and Dubai's flood is not due to cloud seeding. However, it is relatively thought that cloud seeding has caused these side effects, as there were significant weather changes at those cloud seeded areas.
2024.04.16 - Dubai
Dubai's annual rainfall is about 90 millimeters. On April 16th, approximately 160 millimeters of heavy rain fell during 12-hours, some areas even receiving an extraordinary 254 millimeters. In Dubai, this amounted to nearly two years’ worth of rainfall in just half a day.
While many climatologists point to global warming as the main driver behind such extreme weather events, some have raised the possibility that the UAE’s cloud seeding program that is ongoing for more than 20 years.
2024.09.04 - China Chongqing
According to the Chongqing Meteorological Bureau, a total of 158 anti-aircraft shells and 37 rockets were launched for cloud seeding operations. As a result, some areas recorded up to 31 millimeters of rainfall.
On the day cloud seeding was successfully conducted, typhoon-level winds with speeds of up to 34 meters per second struck the area.
Reference
Coffey, R. (2024, August 23). Rain making in Dubai. Was a devastating flood caused by cloud seeding? Forbes. https://www.forbes.com/sites/rebeccacoffey/2024/08/19/rain-making-in-dubai-was-a-devastating-flood-caused-by-cloud-seeding/
Deng, S., Chang, W., & McCarthy, S. (2022, August 18). China is seeding clouds to replenish its shrinking Yangtze River. CNN. https://edition.cnn.com/2022/08/17/asia/china-heat-drought-climate-yangtze-intl/index.html
Fajardo, C., Costa, G., Ortiz, L., Nande, M., Rodríguez-Membibre, M., Martín, M., & Sánchez-Fortún, S. (2016). Potential risk of acute toxicity induced by AgI cloud seeding on soil and freshwater biota. Ecotoxicology and Environmental Safety, 133, 433–441. https://doi.org/10.1016/j.ecoenv.2016.06.028
Sky News. (2024, April 18). Dubai floods: Authorities in the UAE deny cloud seeding caused record rainfall [Video]. YouTube. https://www.youtube.com/watch?v=KdcVDdCR0Q0