If Earth were to lose all its water—liquid, solid, and gas—its appearance would undergo a profound transformation. This hypothetical scenario reveals a planet far removed from the familiar “blue marble” seen from space, exposing a rugged, stark, and entirely new landscape. Such a change would unveil features normally hidden beneath vast oceans and reshape the contours of continents.
Unveiling the Ocean Floors
The exposure of colossal ocean basins, covering approximately 71% of Earth’s surface, would be the most striking visual change. These newly revealed areas would dramatically alter the planet’s topography, showcasing a surprisingly mountainous and canyon-filled terrain. What is commonly imagined as a flat expanse is, in reality, a diverse underwater landscape.
First to emerge would be the continental shelves, the submerged edges of continents that gradually slope away from the coast. These shelves, typically less than 250 meters deep, represent transitional landscapes between dry land and the deep ocean. Beyond these, continental slopes would plunge steeply downward, often carved by deep submarine canyons.
Further into the abyss, vast abyssal plains would spread out, appearing as exceptionally flat expanses at depths typically ranging from 3,000 to 6,000 meters. These plains are formed by fine-grained sediments blanketing the uneven oceanic crust, creating remarkably smooth surfaces. Towering above these plains would be the mid-ocean ridges, Earth’s longest mountain chains, stretching for tens of thousands of kilometers. The Mid-Atlantic Ridge, for instance, would appear as a massive, continuous mountain range.
The deepest points on Earth, the oceanic trenches, such as the Mariana Trench with its Challenger Deep reaching nearly 11,000 meters, would be exposed as immense, elongated depressions. The exposed seafloor would display varying colors due to different minerals and sediments, ranging from light hues on the continental shelves to darker, sediment-covered abyssal plains.
Land Without Its Water
Beyond the exposed ocean floors, the terrestrial landscape would undergo a drastic transformation as all surface water bodies vanish. Rivers would become dry, winding channels, leaving intricate patterns of former flow across the land. These empty riverbeds would appear as deep, eroded gashes, starkly revealing the paths water once carved.
Lakes would turn into vast, dry depressions. Many former lakebeds would be covered in extensive salt flats, shimmering white or off-white where minerals precipitated as water evaporated. Glaciers and ice caps would disappear, exposing underlying rock as barren, scoured mountains and valleys.
The planet’s coastlines would shift dramatically, extending continents outwards and revealing new landforms previously submerged. Areas once shallow coastal waters would become new plains, changing the outline of landmasses. The overall effect would be a significant increase in desertification, as the absence of surface water would leave vast expanses parched and dusty.
A Sky Stripped Bare
Earth’s sky would change profoundly without any water. The atmosphere would be stripped of clouds, rain, and snow, eliminating all familiar weather phenomena like rainbows, fog, or storms.
The sky would appear a perpetual, intense blue during the day, possibly darker in some areas, due to altered light scattering. Earth’s blue sky is primarily caused by Rayleigh scattering, where gas molecules scatter shorter wavelengths of light more effectively. Without water vapor or clouds, which scatter light and can make skies appear whiter, the blue would become even more vivid.
The Ultimate Barren Landscape
A waterless Earth would present an overwhelmingly desolate and stark landscape. The planet would appear predominantly monochromatic, dominated by shades of brown, gray, and exposed rock. The absence of green vegetation, which depends on water, would contribute to this barren visual.
This transformed Earth would resemble celestial bodies like Mars or the Moon. Like Mars, it would be a dusty, rocky world, revealing its underlying geology without the softening effects of water or life. The exposed ocean floors, with their vast mountain ranges and deep trenches, would create a rugged, almost alien topography, distinct from the current blue planet.