Volcanoes, Typhoons, and Acid Rain

^{Image Credit: Nimbus-7 TOMS, NASA/GSFC}

The spreading of sulfur dioxide in the upper atmosphere following the eruption of Mt. Pinatubo, 1991. For a 15-frame movie of the spreading cloud between June 16 and June 30, 1991, click on Movie.

In June 1991, Mt. Pinatubo in the Philippines erupted in a major volcanic outburst just as Typhoon Yunya was approaching. A broad column of ash, water, sulfur dioxide, and other matter was ejected more than 40,000 ft into the stratosphere. The severe weather system of the typhoon and the winds of the stratosphere carried the sulfur dioxide and other ejected particles southwest towards the equator, where they spread into a broad band circling the globe. Within two months, the band covered about 40% of the earth's surface.

At least 17 million tons of sulfur dioxide are estimated to have been ejected, the largest emission from an erupting volcano ever recorded. In the atmosphere, sulfur dioxide combines with water to form sulfuric acid, which is a component of acid rain. Acid rain can have damaging effects on fish, trees, other organisms, and human-made products (e.g., metal, wood, and plastic).

The sulfur dioxide and other matter ejected from Mt. Pinatubo also affected the global weather. The temperature in many parts of the world dropped by nearly one degree Fahrenheit in 1992 compared to the 30-year average. The cold, snowy weather in New Zealand in 1992, the severity of hurricane Andrew in August 1992, and the heavy rains in the US Midwest the following year have all been linked to Mt. Pinatubo's eruption.

The above satellite images were obtained with the Total Ozone Mapping Spectrometer (TOMS) aboard NASA's Nimbus-7 satellite, which operated from 1978 to 1994.

More Cool Stuff

To access the above images go to the Gulf of Maine Aquarium Web site, click on "Space Available," then go to "Weather" and click on "Tracking Sulphur Dioxide from Mount Pinatubo." On that page, click on "Images from NASA's TOMS Satellite":

http://octopus.gma.org

http://skye.gsfc.nasa.gov/eruptions/pinatubo/pinatubo.html

To learn more about the 1991 eruption of Mt. Pinatubo, go to the Cascades Volcano Observatory of the US Geological Service (USGS), click on "The Volcano Disaster Assistance Program (VDAP)," and then on "The 1991 Eruptions of Mt. Pinatubo":

http://vulcan.wr.usgs.gov

http://vulcan.wr.usgs.gov/Volcanoes/Pinatubo/Wolfe/framework.html

To learn more about the effects of Mt. Pinatubo's eruption on the earth's global weather system, go to:

http://www.geo.mtu.edu/eos/education/slide_set1

Other good Web sites about volcanoes, global change, emergency crisis management, and Nimbus-7 information are:

VolcanoWorld, University of North Dakota

http://volcano.und.nodak.edu

The Earth System Science Community (ESSC), ECOlogic Corporation

http://www.circles.org

Flood Management Enhancement Using Remote Sensing Data, SENTAR, Inc.

http://iquest.com/~sentar/NASA/Flood_Management.html

Emergency and Crisis Management: A Remote Sensing Application, University of North Texas

http://www.ias.unt.edu:9876

Public Connection, Rice University and the Houston Museum of Natural Science. Once on that site, click on "Welcome to Planet Earth," then "Resources" and "Biosphere and Bioproductivity Images."

http://space.rice.edu/hmns/connect.html

Virtually Hawaii, University of Hawaii. Once on that site, click on "Virtual Field Trip," then on "Big Island," and check out the volcano pages.

http://hawaii.ivv.nasa.gov

The TOMS Volcanic Sulfur Dioxide homepage at NASA's Goddard Space Flight Center (GSFC):

http://skye.gsfc.nasa.gov

Check out other observations in the Observation of the Week Archive.