How Do Eruptions Capable Of Changing The Global Climate

Big-scale volcanic activity may terminal only a few days, but the massive outpouring of gases and ash can influence climate patterns for years.

By Jason Wolfe

• Virtually the information
• About ASDC
• Most GES DISC
• About PO.DAAC
• Download PDF

When Mount Pinatubo erupted in the Philippines June fifteen, 1991, an estimated 20 million tons of sulfur dioxide and ash particles blasted more 12 miles (20 km) high into the atmosphere. The eruption caused widespread destruction and loss of human life. Gases and solids injected into the stratosphere circled the globe for three weeks. Volcanic eruptions of this magnitude can bear upon global climate, reducing the amount of solar radiation reaching the Globe's surface, lowering temperatures in the troposphere, and changing atmospheric circulation patterns. The extent to which this occurs is an ongoing debate.

Large-scale volcanic action may last only a few days, but the massive outpouring of gases and ash can influence climate patterns for years. Sulfuric gases convert to sulfate aerosols, sub-micron droplets containing nigh 75 percent sulfuric acid. Following eruptions, these droplets particles can linger every bit long as three to four years in the stratosphere.

Mount Pinatubo, June 13, 1991 (Image courtesy of NOAA).

Major eruptions alter the Earth's radiative balance considering volcanic aerosol clouds absorb terrestrial radiations, and scatter a significant corporeality of the incoming solar radiation, an effect known as "radiative forcing" that can last from 2 to three years post-obit a volcanic eruption.

"Volcanic eruptions cause short-term climate changes and contribute to natural climate variability," says Georgiy Stenchikov, a inquiry professor with the Department of Ecology Sciences at Rutgers Academy. "Exploring furnishings of volcanic eruption allows the states to better understand important physical mechanisms in the climate system that are initiated past volcanic forcing."

Stenchikov and Professor Alan Robock of Rutgers University with Hans Graf and Ingo Kirchner of the Max Planck Institute for Meteorology performed a series of climate simulations that combined volcanic droplets observations from the Stratospheric Aerosol and Gas Experiment II (SAGE Two) available from NASA'due south Atmospheric Science Data Centre (ASDC), with Upper Atmosphere Inquiry Satellite (UARS) data from NASA's Goddard Earth Science Data and Data Services Middle (GES DISC).

The inquiry team ran a general circulation model developed at the Max Planck Establish with and without Pinatubo aerosols for the two years following the Pinatubo eruption. To study the sensitivity of climate response to sea surface temperature, using data from NASA's Physical Oceanography Distributed Active Annal Middle (PO.DAAC), they conducted calculations with climatologically hateful sea surface temperature, also as with those observed during particular El Niño and La Niña periods.

Volcanic ash, like this from Mountain St. Helens, is non actually ash, but tiny jagged particles of rock and glass. (Image courtesy of the USGS, from the USGS Fact Canvas 027-00).

By comparing the climate simulations from the Pinatubo eruption, with and without aerosols, the researchers found that the climate model calculated a general cooling of the global troposphere, merely yielded a articulate winter warming design of surface air temperature over Northern Hemisphere continents. The temperature of the tropical lower stratosphere increased by 4 Kelvin (iv°C) because of droplets absorption of terrestrial longwave and solar near-infrared radiation. The model demonstrated that the direct radiative effect of volcanic aerosols causes general stratospheric heating and tropospheric cooling, with a tropospheric warming pattern in the winter.

"The modeled temperature change is consistent with the temperature anomalies observed after the eruption," Stenchikov says. "The blueprint of winter warming post-obit the volcanic eruption is practically identical to a design of wintertime surface temperature change caused by global warming. It shows that volcanic aerosols force fundamental climate mechanisms that play an important role in the global change process."

This temperature blueprint is consistent with the existence of a strong phase of the Arctic Oscillation, a natural design of circulation in which atmospheric pressure level at polar and middle latitudes fluctuates, bringing college-than-normal pressure over the polar region and lower-than-normal pressure at almost 45 degrees north latitude. It is forced past the droplets radiative result, and circulation in winter is stronger than the aerosol radiative cooling that dominates in summertime.

Homo-fabricated, or "anthropogenic" emissions can make the consequences of volcanic eruptions on the global climate system more severe, Stenchikov says. For instance, chlorofluorocarbons (CFCs) in the atmosphere start a chain of chemical reactions on aerosol surfaces that destroy ozone molecules in the mid-breadth stratosphere, intensifying observed stratospheric ozone depletion.

"While we have no observations, the 1963 Agung eruption on the island of Bali probably did not deplete ozone as in that location was little atmospheric chlorine in the stratosphere. In 1991 later the Pinatubo eruption, when the amount of CFCs in the stratosphere increased, the ozone content in the mid-latitudes decreased by 5 percent to 8 percent, affecting highly populated regions," says Stenchikov.

NASA and the National Science Foundation have funded Robock and Stenchikov to study the Pinatubo eruption in more than item, and to conduct another model comparison with the volcanic aerosol data set. They plan to combine SAGE 2 data with available lidar and satellite data from various DAACs to improve their existing data set.

By understanding the impact of large volcanic eruptions on World'southward climate arrangement in more detail, possibly scientists volition be in a better position to advise measures to lessen their effects on people and natural resources.

References

Kirchner, I., K. Stenchikov, H.-F. Graf, A. Robock. J. Antuna, Climate model simulation of winter warming and summertime cooling following the 1991 Mount Pinatubo volcanic eruption, J. Geophys. Res., 104, xix,039-19,055, 1999.

Stenchikov, Georgiy 50., Ingo Kirchner, Alan Robock, Hans-F. Graf, Juan Carlos Antuna, R. Chiliad. Grainger, Alyn Lambert, and Larry Thomason, 1998: Radiative Forcing from the 1991 Mount Pinatubo volcanic eruption. J. Geophys Res.103(D12), pp. 13837-13857.

For more data

NASA Atmospheric Scientific discipline Data Eye (ASDC)

NASA Goddard Earth Sciences Data and Data Services Center (GES DISC)

NASA Physical Oceanography Distributed Agile Archive Center (PO.DAAC)

About the remote sensing data used
Satellite	Stratospheric Aerosol and Gas Experiment 2 (SAGE 2)	Upper Atmosphere Research Satellite (UARS)	NOAA -seven, -nine, -11, and -fourteen polar orbiting satellites
Sensor			Advanced Very High Resolution Radiometers (AVHRR)
Parameter	volcanic aerosols and climate alter	volcanic aerosols and climate change	volcanic aerosols and climate change
DAAC	NASA Atmospheric Science Information Center (ASDC)	NASA Goddard Globe Sciences Information and Information Services Heart (GES DISC)	NASA Physical Oceanography Distributed Agile Archive Center (PO.DAAC)

Source: https://earthdata.nasa.gov/learn/sensing-our-planet/volcanoes-and-climate-change

Posted by: grillothiseatchat.blogspot.com

Share this post