Canals that divert ocean water into massive lakes within deserts. These lakes should have outlets that lead some of the water back to the oceans to prevent overflowing.
Global sea levels are rising at an unprecedented rate and they bring with them numerous problems that will greatly affect humans, including flooding, shoreline erosion, and hazards from destructive storm surges, especially since nearly 40% of the world's population live in coastal areas. With this idea, we can:
reduce the problems that rising sea levels cause, such as flooding
turn arid desert areas into fertile greenlands, alongside other efforts
provide an alternative means of transportation through these areas
Humanity has been building canals for hundreds of years. The latest technology on canal building can be used here, provided the will, funding, and manpower are available.
This project will require an enormous amount of funds, more than any one person (or country) can undertake. However, the COVID-19 pandemic demonstrated that humanity can coordinate, with many people - billionaires, millionaires, and ordinary citizens - contributing to efforts to alleviate the effects of the pandemic on others. So, I propose the establishment of a public-private organization that directs the effort and coordinates responses from both governments and private citizens, including the collation of funds for undertaking this project.
Such a project will require enormous forms of energy. However, given that the site of this particular project is the desert, I imagine that the primary form of energy used will be solar energy. Using any other form of energy isn't ideal as it will lead to the release of carbon dioxide, which will, in turn, worsen global warming.
Application in Agriculture
Sea water is not suitable for agriculture. However, some of the water diverted through these deserts can be desalinated and, subsequently, used to grow food. Given the fact that desert soil is low in nutrients, efforts will have to be made to rectify this.
While reading for this idea, I discovered there are numerous obstacles to it.
I've addressed some of them, like funding and energy. Another objection that I came across many times is that such efforts won't reduce the oceans' level by much. However, the goal isn't to empty the oceans. The goal is to reduce the level a little so that it doesn't threaten our way of living, among others. For that reason, we don't need to divert a significant volume of water.
Another potential obstacle is that sea water will disrupt the ecosystems of the paths they carve through the deserts. However, I believe this can be contained by ensuring the water does not overflow and flood their surroundings; hence, the need for outlets that lead back to oceans like I suggested.
How can we make this idea better? What other potential obstacles exist and how can we combat them?