What Hawaii's Kilauea and Guatemala's Fuego Volcanoes Mean for the Climate

When volcanoes like Hawaii's Kilauea and Guatemala's Fuego erupt, they spew ash, gas and other particles into the air, and those particles—big and small—can have an impact on the climate and environment.

Hawaii's Kilauea erupted in May and has been expelling hot, slow-moving liquid rock for a month now along with dangerous gases. Fuego erupted over the weekend and again on Tuesday night while rescuers were attempting to find anyone left in the destruction, The Week reported.

Different volcanoes can have slightly different byproducts: The volcano in Hawaii emitted a lot of sulfur dioxide, a greenhouse gas that can lead to acid rain; Fuego released pyroclastic flows, a mixture of the volcanic matter and the gases.

"They inject ash, water, often sulfur dioxide," Valentina Aquila, an assistant professor in the Department of Environmental Science at American University told Newsweek. "The result is a cooling of the surface as an average," she said. "This is particularly evident for very big volcanic eruptions," she added, like the massive eruption of Mount Pinatubo in 1991. "Pinatubo actually changed the climate."

Despite the fact that the volcanic eruptions in Hawaii and Guatemala have been devastating for those in the area, claiming lives and homes, they're relatively small eruptions compared to some of the larger eruptions of the past. "The volcanic eruptions we're seeing now, they're much smaller," Aquila said, but they're also far more frequent than large eruptions like Pinatubo. When the products of all of the smaller eruptions are combined, they can have an effect on the atmosphere.

The eruptions can actually cause a change in the temperatures around the Earth. "It has overall a cooling of the surface of the Earth but a warming of the lower stratosphere," Aquila explained. This happens due to the sulfur dioxide and other greenhouse gases that enter the atmosphere after the eruption.

When the sulfur dioxide enters the stratosphere, it causes chemical reactions and reflects the infrared radiation from space that normally warms the Earth, and this has a cooling effect on the Earth's surface. Chemical reactions in the atmosphere caused by the eruptions can contribute to the depletion of the ozone, however. The ozone helps block harmful ultraviolet radiation. Additionally, those reactions can create a heat-trapping effect of the radiation Earth itself gives off and can cause warming that way.

It's the larger, heavier particles—like ash—from a volcanic eruption that cause more problems in the vicinity of the actual volcano. People on the ground and near the volcano will actually be affected by the falling ash, gases in the air, lava and possible acid rain.

Whether or not the recent volcanic eruptions will change the climate is still unknown and dependent on whether the volcanoes continue to erupt—but they could have the potential to make things a little cooler for a bit.

Fissure 21 of the Kilauea volcano erupts in the Leilani Estates subdivision of Pahoa, Hawaii, on May 22. The gases released after a volcanic eruption can enter the upper atmosphere and sometimes cause cooling of the Earth. Ronit Fahl/Getty Images