Monday, December 14, 2020

Is China Moving Toward Geoengineering?


Earlier this month, the State Council of China (its main administrative body) announced that it was planning to expand its weather-modification efforts to cover an area of about 5.5 million square kilometers, which is more than half the size of the United States.  In addition to rainmaking (which the announcement called "precipitation control"), the government-funded efforts include prevention of hailstorms, enhanced accuracy of weather forecasts, and emergency response plans to deal with crises such as forest fires.


This is not China's first venture into weather modification.  To prevent rain from dampening the festivitives at the opening of the 2008 Olympics in Beijing on August 8 of that year, over a thousand rockets filled with silver iodide crystals were fired into the skies prior to the event.  Whether the party would have been rained out without the rockets is something we'll never know, but the Party leaders didn't want to take a chance that rain would spoil their parade.


Not counting things such as Indian rain dances, the history of scientific weather modification goes back to the late 1940s, when meteorologist Bernard Vonnegut (brother of author Kurt) and the Nobelist Irving Langmuir independently found ways to encourage clouds to form precipitation.  Vonnegut's method involved silver iodide crystals, and the U. S. Army showed in large-scale experiments that spreading finely-divided crystals into actual clouds could cause or increase rainfall under certain conditions. 


In the U. S., large-scale cloud-seeding efforts are no longer common, although numerous experiments with hurricanes and conventional storms were carried out as late as the 1970s.  For one thing, it is difficult to do a controlled experiment with cloud seeding, as no two clouds are ever alike and the ideal of changing only one variable (to seed or not to seed) can never be achieved.  Consequently, the typical outcome of an experiment, which can cost many thousands of dollars in flight time, shells, or rockets, is "well, maybe it did something, but we're not sure."  Another issue is that if more rain comes down in location A, that same rain can't also fall in location B, and if A and B are in different states, for example, you have a potential conflict between administrative entities.


That may be one reason that, after employing weather modification to a limited extent in theVietnam War, the U. S. signed the Environmental Modification Convention in 1978, which  bans the use of weather modification for hostile purposes.  The Peoples' Republic of China is also a participant in that convention, but that may not make adjacent countries such as India feel much better, as China could always claim that their cloud seeding was for peaceful purposes.


The term "geoengineering" is usually reserved for technological activities that would affect the entire globe, not just a part of it.  For example, at various times scientists have floated the idea that to combat global warming, we should inject a lot of sulfur dioxide particles into the air in order to reduce the influx of radiation to the earth's surface and counteract the greenhouse effect of rising carbon dioxide levels in the atmosphere.  So far, weather modification efforts on the scale that we have seen historically don't amount to geoengineering.  But if the area in which such work is being done gets large enough, and 5.5 million square kilometers is pretty large, then you can begin to wonder whether we are putting the robustness of large-scale weather systems to a test.


We already know that seemingly subtle shifts in things such as the El Niño circulation off the Pacific coast of South America can have significant effects on our weather here in North America.  I don't know anything about typical weather patterns in the Far East, but it only stands to reason that mucking around with the weather over a large enough area of China is going to have some kind of effect in areas outside the region as well. 


Of course, this assumes that everything the State Council wants to do is successful.  If the history of weather modification tells us anything, it says that the best-laid plans in this field turn out to work less well than the designers hoped they would.  But most of the large-scale experiments in cloud seeding were carried out decades ago, before the advent of modern supercomputer-based weather modeling and enhanced automated weather data acquisition.  It's quite possible that with modern weather-forecasting technology, something closer to a truly controlled experiment can be carried out that will give us a better idea of whether all that silver iodide is doing any good, or whether it's just as useless as shooting off fireworks.


China has the dubious advantage of not having to worry about interstate lawsuits or any of the other administrative inconveniences that go with democracy.  Dictatorships can do large-scale, long-term things that democracies find difficult.  It's not an advantage that I personally think is worth the cost, but if the State Council decides to do a thing, there's not much anybody else can do to stop them, whether it's weather modification or a one-child policy. 


If the experiments turn out to be successful, I doubt that China will be very generous in sharing the results with the rest of the world, except maybe to brag.  And even if everything works as well as they hope, I'm not sure how applicable the results will be for the rest of the world, unless Russia or some other country dealing with huge land masses gets interested. 


You've probably heard someone say, "water is the new oil," meaning that as populations increase and live in cities with modern water supplies, the need for clean water may outstrip the need for fossil fuels.  While water resources will always be important, if weather modification turns out to be as useful as China thinks, that will add a new factor to the question of where future generations will find enough water to use.  My suspicion is that the basic natural processes that put water in the air in the first place are not going to change that much by means of weather modification, and any changes China or any other country can make will be relatively small-scale and short-term.  But I've been wrong before.


Sources:  The South China Morning Post carried an article describing the Chinese State Council's announcement of its plans for weather modification at  I also referred to the Wikipedia articles on cloud seeding, the Environmental Modification Convention, and El Niño.

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