Green Group discussion

The usual type of cloud seeding is used to promote rain by putting a chemical into clouds that might have enough moisture in them to produce rain if triggered to do so.

The issue of cloud seeding while rooted in real science has not been shown to be able to predictably create measurable rainfall on demand. It does rain in areas using it on occasion and is used by various countries on a regular basis.

Cloud seeding can also break up clouds by making it rain now instead of later which is supposed to lessen the possibility of flood activity. Arid regions in the Mid East, Asia, and Africa are using it for promoting agriculture as well as helping to fill reservoirs. Some countries have used cloud seeding to keep the skies clear for important events.

Cloud seeding can also disperse fog by making it condense into liquid moisture which falls to the ground.

Cloud seeding is also used to break up hail storms by preventing the formation of hail.

Cloud seeding is now being considered as a way of making clouds more reflective so sunlight is reflected back into the sky and doesn't reach Earth's surface. This would lower the temperature, and if done globally might lower the Earth's average temperature. This is being tested right now in San Francisco using table salt.

Cloud seeding receives little publicity globally but locally where it is practiced the discussions range from positive to negative. It's said that it doesn't do anything, to it does. That the chemicals will cause pollution or they won't. Its okay to tamper with the Natural World using artificial means to change it, to it isn't okay, with reasons ranging from science based, to personal feelings, to beliefs held by indigenous people.

The usual chemical is silver iodide because it mimics the formation of ice crystals which then have water moisture condense on them. Other substances can be used, including dry ice, and table salt, which is used in warm areas because salt absorbs moisture and thus facilitates the creation of water droplets. Propane and liquid nitrogen can also be used as cloud seeding mechanisms.

A new method of cloud seeding is using ions to seed the clouds. This could prevent chemical pollution happening when large quantities of chemicals are used in the same areas over and over again.

It is estimated that cloud seeding might contribute 1.5 to perhaps 3 percent of snow pack cover on mountains.

Cloud seeding was used in the Viet Nam War to increase seasonal rains and it supposedly extended the rain season by an extra month. The only way for this to have worked work would have been for an extremely large amount of chemicals used for extended periods of time which certainly polluted the ground during the seeding process.

The amount of money spent on cloud seeding has been increasing steadily and will probably be double in 2030 compared to today.

The cloud seeding experiments happening now in San Francisco were not hidden, neither were they given a lot of publicity to minimize negative responses. The San Francisco tests are using table salt, a cheap alternative to silver iodide. They are not testing the ion process which seems to be far less polluting especially if it was ramped up to global use to provide extra cloud cover to minimize global warming.

https://www.vynzresearch.com/aerospac...

https://source.colostate.edu/cloud-se...

https://www.scientificamerican.com/ar...

Moisture droplets and hail normally form around tiny dust particles. These are wind borne so if there are none, it won't rain yet, but the wind brings moisture and dust to a new location all the time.
If the air is saturated with moisture of course that will start to fall but I'm wondering if cloud seeding could be done just with fine dust like loess.

We're hearing that the Arabian Gulf states cloud seed and this may have worsened recent downpours which caused flooding.

Geo engineering clouds also includes cloud brightening.

https://phys.org/news/2024-06-marine-...

"One proposed solution is geoengineering to reduce the amount of heat that makes its way into the atmosphere. One such approach is called marine cloud brightening (MCB), which involves injecting massive amounts of sea salt into the lower atmosphere to serve as tiny mirrors, bouncing heat and light from the sun back out into space.

For this new study, the researchers investigated how this might work for one part of the world and to model the potential impacts.

The work involved configuring established climate models to show what would happen if artificial stratocumulus clouds were created under two different scenarios, both over the North Pacific: one over the temperate latitudes and the other over sub-tropical waters. Under both scenarios, the artificial clouds were generated and maintained for nine months every year for 30 years.

The researchers found that the artificial clouds would reduce temperatures in the western U.S., primarily California—reducing risk of dangerously high temperatures by as much as 55%. But they also found the same clouds would reduce rainfall amounts, both in the U.S. and other parts of the world."

More information: Jessica S. Wan et al, Diminished efficacy of regional marine cloud brightening in a warmer world, Nature Climate Change (2024).
https://www.nature.com/articles/s4155...
Journal information: Nature Climate Change

Excellent article / opinion piece in The Guardian that warns about the dangers of geoengineering approaches to mitigating climate change:

It took more than a century of carbon emissions before we could detect that our climate is changing and even longer to attribute those changes, unequivocally, to anthropogenic carbon emissions. It was only in 2015 in Paris that most countries accepted that the world is warming and that we are to blame (and 2023 for UNFCCC to mention fossil fuels in a COP outcome).

Now, proponents of geoengineering are proposing to bash the climate with a whole new hammer, and one that engages some of the most poorly understood aspects of the climate system, including aerosols, clouds and regional rainfall patterns. We know that this would trigger much more uncertainty on outcomes, in particular in the case of poorly planned, unmanaged, uncoordinated injections of various substances in the high atmosphere, with no governance framework. Surely, we should insist on the same level of scientific diligence as has been devoted to understanding the regional consequences of greenhouse gas emissions.

Climate model simulations can provide an indication of what might go wrong but can provide no reassurance of what will go right. So far there has been no rigorous modelling assessment to explore different solar geoengineering scenarios and no formal intercomparison of the sensitivity of the climate to such interventions, let alone the impacts on regional weather and climate variability.

‘Termination shock’: trust our expert warnings on geoengineering’s planetary risks — https://www.theguardian.com/commentis...

What is ironic is that we are already geoengineering the planet. So far we have a very poor understanding of how or why things are happening.

There are several ways of going forward.

One way would be to change out the majority of substances that we use for substances that don't have a negative impact, preferably a positive impact on the environment. This would cost a great of money, take a great deal of research, and major changes to things until we can figure how to get the same results.

Another way is to continue to dump massive amounts of substances that impact the environment into the environment and add to that massive amounts of substances to counteract the negative impacts. This wouldn't clean up anything. More than likely more counter measures would be needed to counteract the original counter measures.

A third way is to change the way things are done in a positive way. This would involve everyone and have positive impacts on the environment. A lot of people and companies would have to be compensated for what they lose. It would take a long time and a lot of money to sort things out.

One natural example of cloud seeding and geoengineering both, is the Sahara. Fine dust blows off the Sahara Desert and enters high levels of the atmosphere. It crosses the Atlantic and passes / falls on the Canary Islands, Caribbean Sea, West Indes, the north of South America, and Florida.
Nowadays, this dust contains pollutants from people burning trash and tyres in the open air.
For centuries, this dust has brought fertiliser and seeded rain to the western lands and seas.