Cooling the Lava By: Usman Hanif and Andrew Friedman

Thorbjorn Sigurgeirsson Heimaey University of Iceland, Physical Laboratory Largest island of Vestmannaeyjar Sveinn Eiriksson McPhee flashes back to February 1973, when a small town and harbor on an offshore island is threatened by red-hot lava. Residents spray the moving lava front with fire hoses. Their televised efforts produce clouds of steam. The Civil Defense Council in the Reykjavik National Emergency Center watches Thorbjorn's experiment with interest. The Center is established in 1962 as a command-post bomb shelter for nuclear war. Within a year the Council worries about the effects of lava flows on the Atlantic Ocean and the islands of Vestmannaeyjar. The Council broadens its charter to include acts of God.

What Happened? Eldfell ("fire mountain" in Icelandic) is a volcano on the island of Heimaey in the Vestmannaeyjar 15 miles (25 km) south of Iceland. In January of 1973, an eruption began along a 1.5 mile (2 km) long fissure not far from the center of the town of Vestmannaeyjar. The fissure extended across the entire island, producing a spectacular curtain of fire. Nearly all of the island's 5,300 residents were evacuated to the mainland. Heimaey accounted for 2 percent of Iceland’s total population but produces 1/12 of its export income Size of Manhattan south of New York However the amount of lava that came over the region in 1973 was enough to cover all of new york all the way up to the top of the twin towers - Very Valuable to iceland, more than what New York is to the United States. Producing a 1/12 of all of Iceland Exports!

After Before Some feel vibrations but think it's from the central heating or settling of earth common to Iceland. A seismometer is a geological instrument used to measure intensity and location of earth vibrations like earthquakes and volcanoes. Mainland seismometers assign the vibrations to other volcanoes or do not indicate an eruption. Two seismometer readings can give an unclear or confusing location of an epicenter. A third seismometer reading would allow scientists to locate the center of activity. Without a third reading the uprising magma is not established under Heimaey. One resident sees the earth crack open and leaves with her sons never to return. Two others begin taking pictures of the lava curtain rising. Others leave for a night or two. Four thousand calm residents depart the island in three hours.

Timeline of the Catastrophe Within two days, activity became localized to a central vent and fire fountains constructed a cinder and spatter cone 350 feet (100 m) above sea level. A central vent connects the magma chamber to the open vent on top of a volcano, and is maintained open by the continuous release of volcanic material. Strong winds blew tephra from the eruption and buried homes in the town Vestmannaeyjar. In proximity to the crater, huge volcanic bombs were released. These bombs were ejections of molten lava that flew high into the air, became spherical, and, with contained gases, sometimes exploded fireworks. Bombs generally molten and when they landed red-hot liquid would be poured out.

Lava Flow The initial eruption rate was close to 130 cubic yards (100 cubic meters) per second. By the middle of April, the eruption rate had dropped to 7 cubic yards (5 cubic meters) per second. The eruption stopped in early July. In mid-February small molten lava streams appear near the bottom on its north side. The north side of the mountain breaks loose. It begins to move towards the port. Lava flows approach the harbor's breakwater at a rate of one hundred feet a day. It is likely to cross the breakwater and fill the harbor. Thorbjorn plans to pump seawater below surface in its molten cracks to cool them. They pump thirty million gallons of seawater on the lava field to cool it.

The system pumps twenty-three million gallons daily for one hundred and three days. Each time the lava stops pipes are moved closer to the crater.

Historical Attempts to Control Lava The U.S. Army Air Corps bombs an insulating vent on the Mauna Loa volcano in 1935. The attempt clogs it with debris and forces lava flows aside Hawaiian natives accept eruptions as acts of God. They pray and make offerings The National Oceanic and Atmospheric Administration builds small buildings in 1986 to house expensive instruments. They protect them with a barrier from lava flowing down from eleven thousand feet on Mauna Loa. Barriers are proposed to protect Hilo, which is Hawaii's second-largest city and port. Firefighters do not stop or divert lava flows due to legal costs

Iceland and Hawaii are the world's most productive geophysical hotspots. Thrusting heat hits the underside of sixty-mile thick earth crusts. The rising heat repeatedly punches up as plates move. Hawaiian Islands are created as the Pacific crust passes the heat source. Hawaii's oldest islands Niihau and Kauai are volcanic peaks for five million years. High peaks are Mauna Kea and Mauna Loa. Iceland forms in the North American Plate and Eurasian crust. It sits on the Mid- Atlantic Ridge. Iceland's west moves with North America and its east moves with Europe. The extreme east and west sides of Iceland are old rock of fourteen million years. Iceland's center is made of young and fluid rock with no significant geological age. The Mid-Atlantic Ridge spreads a forty-mile wide center in the Icelandic mainland. Iceland's center and Vestmannaeyjar are both on a line of maximum action called the volcanic zone.

Cooling Of The Lava Ending Population on Heimaey dropped by 12 percent Much of the island is a pumice desert after the eruption The eruption narrowed the harbor from half a mile wide to 500 feet wide so it is now less exposed to eastern wind and waves The volcano still releases heat which residents utilize in a central heating plant Cooling the lava flows cost $1.5 million The new cost savings from the natural heating, paving materials for streets, and harbor improvements save $30 million