If we lift tens of millions of tons of sulfur dioxide into the stratosphere, we can mitigate the consequences of global warming, they are sure.
Researchers from Germany and the United States carried out calculations, from which it follows that the simplest and most economical way to combat global warming is spraying from airplanes in the stratosphere of toxic sulfur dioxide. The method can have minor side effects, such as the destruction of the ozone layer. But it is quite inexpensive – just over $ 20 billion a year. The corresponding article was published in the journal Science.
Scientists proposed to use sulfur dioxide (SO2, SO2) for combating warming. This is a very toxic compound with a sharp unpleasant odor, similar to what a newly lit match produces. Its feature is that it effectively reflects visible light. When in 1991 the Filipino Pinatubo volcano erupted a lot of this gas, the average temperature in the Northern Hemisphere fell by 0.5-0.6 degrees from the previous years. According to the calculations of the authors of the first work, in order to avoid an increase in the average annual temperature by two degrees by the end of the century, it is enough to throw 20 million tons of SO2 into the atmosphere – approximately as if Pinatubo erupted every year.
To ensure that the gas does not rapidly escape from the atmosphere with rain, it must be raised to the stratosphere above 12 kilometers, since rain clouds do not form there. This will require many thousands of multi-engine flights a year. In the stratosphere is ozone, the concentration of which from such frequent flights (the products of combustion of kerosene destroy it) will noticeably decrease. However, sulfur dioxide blocks ultraviolet radiation as well as ozone. But SO2 is very cheap – $ 500 per ton. Even taking into account the delivery to the stratosphere, the project will cost only $ 20 billion a year. However, it should be conducted 160 years in a row, that is, the total direct cost will exceed three trillion dollars. Lower temperatures can lead to a fall in yields in the northern countries, that is, the initiative will give and some indirect costs, the size of which, however, the authors of the work did not expect. It is almost impossible to calculate the future decline in crop yields and the increase in heating costs in the Nordic countries due to the incompleteness of the available data.
It should be noted that Russia has recently signed the Paris Agreement, whose members pledge to actively combat global warming. Scientists offer their methods just to fulfill this agreement. As you know, the United States, due to the position of President Trump, has already abandoned the agreement, but Russia is still in it. Thus, it is one of the countries that are addressing the new initiative of American and German scientists. In parallel, a number of scientists raise the question that global warming may not be as harmful as it was thought, for example, it seems to lead to landscaping of deserts and growth of crops.