If all the crust above sea level were to rise, the Earth would look very different. The continents would be much larger, as the continental shelves would be exposed. The oceans would be much smaller, and the sea level would be much lower. This would have a profound effect on the climate, as the oceans would no longer be able to absorb as much heat from the sun. The Earth would become much hotter, and the climate would become more extreme.

Here are some specific changes that would occur:

* The continents would be much larger. The continental shelves, which are currently submerged, would be exposed. This would add a significant amount of land to the continents, making them much larger.

* The oceans would be much smaller. The oceans would shrink in size, as the sea level would drop. This would have a profound effect on the climate, as the oceans would no longer be able to absorb as much heat from the sun.

* The sea level would be much lower. The sea level would drop by about 120 meters (400 feet), exposing the continental shelves. This would have a major impact on coastal communities, as they would be forced to relocate.

* The climate would become much hotter. The Earth would become much hotter, as the oceans would no longer be able to absorb as much heat from the sun. This would lead to more extreme weather events, such as hurricanes, droughts, and floods.

* The Earth would become more volcanically active. The Earth would become more volcanically active, as the pressure on the Earth's crust would be reduced. This could lead to more volcanic eruptions, which could have a devastating impact on human populations.

Overall, the Earth would look very different if all the crust above sea level were to rise. The continents would be much larger, the oceans would be much smaller, the sea level would be much lower, and the climate would become much hotter. This would have a profound effect on human populations, and could lead to a major global crisis.