The article [7] formulates a set of three technologies that should cope with the greatest threat to humanity — climate change — at minimal cost. The main technology will be "Sunny Rain". The eruption of the underwater volcano Hunga in 2021 resulted in the release of 439 million tons of water into the atmosphere, which led to an increase in the water vapor content by 10-15%. This is the largest increase in the vapor content in the atmosphere in recorded history. According to scientists, the consequences of the eruption of this volcano can lead to an increase in temperature on the planet in the next 5 years. Therefore, the second direction of our work was the development of measures to prevent eruptions of shallow underwater volcanoes, since they will contribute to climate change. Articles [4,7] propose a technology to prevent eruptions of underwater volcanoes at shallow depths. The measures we have developed can be used by Japan, Italy and Greece to prevent eruptions of shallow underwater volcanoes (Kiki, Marsili, Colombo) located on their territory. As a third technology, scalable solutions for reducing carbon emissions in various industries, decarbonization technologies are considered. A list of shallow underwater volcanoes that are likely to emit water into the atmosphere, which turns into water dust, has begun to be compiled. If the governments of Japan, Italy and Greece, which have shallow underwater volcanoes (Kiki, Marsili, Colombo), prevent eruptions of these volcanoes, this will provide electricity to these countries, save many of their citizens from dying and save humanity from the biggest threat - climate change - in the most inexpensive way possible!