Warming Water

OCEAN

Covering 71 percent of our blue-marbled planet, the seas now absorb so much human-generated CO₂ and energy from the sun that seawater chemistry and temperatures are endangering many organisms. Changes in the marine environment affect what thrives in the water and what we can harvest from it. Sea-level shifts are altering coastlines and undermining buildings, posing risks to human life.

Rising Seas

Reengineering coastal infrastructure and investing in water barriers and diversion systems can help protect against storm surges and floods.

LAND

The dynamic interactions between climate change and freshwater resources on land are critically tied to the availability of good-quality water for human use. Today at least half the world’s population relies on groundwater for safe drinking water. With projected urban growth expected to increase demand by 55 percent by 2050, we’ll have to manage future water use carefully.

Low Snow

Springtime snow cover in the Northern Hemisphere will likely drop 10 to 30 percent by 2100, making comprehensive water management crucial.

ICE

The freshwater that was once frozen in the Arctic, Greenland, Antarctica, and global alpine regions is melting and spilling into the world’s oceans, streams, and soil. As more ice melts, rivers and watersheds will fill at first. But as the ice dwindles, so will the runoff—and the available freshwater. If conservation doesn’t stem the problem, water-use restrictions loom.

Not-so-perma frost

When permafrost thaws, land changes. People in the north rethink roads and buildings, relocate cellars that store frozen game, and move from vulnerable areas.