How Is Climate Change Affecting Water?

Climate change is having the most pronounced effect on water. Around the globe, the warming atmosphere, land and oceans are causing fundamental changes to the water cycle and weather patterns.  Some areas are experiencing more intense precipitation events, while others are witnessing extended droughts.

In New Jersey, climate scientists predict that we are likely to see both of these seemingly contradictory impacts. In late 2016, the U.S. Environmental Protection Agency wrote about New Jersey: “Rising temperatures and shifting rainfall patterns are likely to increase the intensity of both floods and droughts.” (What Climate Change Means for New Jersey.” EPA 430-F-16-032. August 2016)

Simple physics explains these results. As the surface of the oceans and other water bodies get warmer, more water evaporates into the atmosphere. As the atmosphere also heats up, the warmer air can hold more moisture: A roughly one degree increase in the thermometer results in about 4 percent more water vapor. More moisture in the air results in heavier rain storms and can cause more severe hurricanes and tornadoes.

Because warmer air can hold more moisture, more water is also sucked into the atmosphere from the ground and from plants through evaporation and transpiration. As the warmer atmosphere pulls more moisture from soils and plants, drought conditions are exacerbated during periods of low precipitation.

The impacts of climate change on water are reinforced by the expansion of hard surfaces, like parking lots, roadways and rooftops. These developments prevent water from soaking into the ground, which creates more flooding during periods of high precipitation and reducing the replenishment of groundwater during drier times.

Because much of the water in our streams and rivers originates as groundwater, particularly during dry periods, blocking the replenishment of groundwater through infiltration also results to lower flows in our streams in river.

All over the world, you can witness evidence of a changing water cycle and its impacts on communities. Too much, too little, and too dirty. Watch the video to learn about ways we can adapt to a changing climate.