Khi không khí đạt đến một độ cao, nơi nhiệt độ thấp, hơi nước ngưng tụ thành mây, mưa lên trên bề mặt của trái đất, hoàn thành chu kỳ nước. [[Tiềm ẩn nhiệt ngưng tụ nước khuếch đại đối lưu, sản xuất các hiện tượng khí quyển như gió, cơn bão và chống cơn bão. | 144 5 Known Knowns and the Unknown expenditure in the region of 4 of the global economy is called for. It should be noted that this money does not disappear like investments in modern banks are prone to do it gets spent on real physical infrastructure. It represents a good old Keynesian boost to the world economy. The Unknowable From the miniscule scale of nano-engineering where molecules are massaged to form novel materials to electrical engineering on the macroscopic scale where massive components are manipulated to build power stations and other large electrical systems in general the technical problems that are encountered by scien-tists engineers have known or knowable solutions. Because of this most technologists would probably aver that engineering in the physical world is largely child s play by comparison with the complexities and imponderables inherent in the social version where problems seemingly have no definitive answer or the answers are politically unpalatable or they have a myriad of answers all of which generate further problems Unknown knowns or perhaps known unknowns Who knows The social engineering of reluctant and recalcitrant mankind away from its drug-like dependency on fossil fuels which is absolutely essential to a successful transition to renewable energy seems a daunting task if just democratic and market levers are employed. On all the available evidence it will call for voter and consumer manipulation of a truly Machiavellian quality and scale to shift entrenched attitudes in the market fixated democracies. It is difficult to be confident that this will ever happen. What is really needed is wise leadership. But politicians who are sufficiently knowledgeable to be wise seem no longer to exist. Returning to the world of do-able engineering an effective ecogrid as we have now seen can be built but it will be necessary to divert a considerable proportion of the globe s human resources and capital towards implementing this task. The .
