What is the best way to help after a disaster?

Disaster relief agencies such as the Red Cross are in vital need of money after a disaster to purchase necessary items for victims or provide financial support to them. Call your local chapter of the Red Cross to find out how to help. Donating food or clothing places additional burdens on the agencies in the immediate aftermath of a disaster, as personnel are not available to sort, clean, or distribute donated goods.

How did a map help stop the spread of cholera?

During an 1854 cholera outbreak in London, a physician named John Show mapped the distribution of cholera deaths. His map showed that there was a high concentration of deaths in an area surrounding one specific water pump (water had to be hand-pumped and carried in buckets at the time). When the handle was taken off of the water pump, the number of cholera deaths plummeted. When it was determined that cholera could be spread through water, future epidemics were curbed. This was the beginning of medical geography.

What are incidence maps?

Researchers at such institutions as the Centers for Disease Control and Prevention (CDC) use incidence maps, which plot where and how people have been infected or exposed to such potentially harmful viruses as the influenza, the Ebola Virus, West Nile Virus, and HIV in order to understand the rate of transmission as related to geography. An incidence map may help scientists figure out the origin of a disease and where and how quickly it is spreading. Global incidence maps are of increasing importance in the fight against potentially harmful biological disasters.

Which natural disasters doesn't Southern California experience?

While urban southern California is plagued by earthquakes, wild fires, floods, landslides, and tornadoes (yes, even tornadoes), they rarely receive snowstorms or hurricanes.

VOLCANOES

What are volcanoes?

Volcanoes are the result of magma rising or being pushed to the surface of the Earth. Hot liquid magma, which is located under the surface of the Earth, rises through cracks and weak sections of rock. The mountain surrounding a volcano is formed by lava (called magma until it arrives at the Earth's surface) that cools and hardens, making the volcano taller or wider or both.

What is the Ring of Fire?

If you were to look at a map of the world's major earthquakes and volcanoes, you would notice a pattern circling the Pacific Ocean. This dense accumulation of earthquakes and volcanoes is known as the Ring of Fire. The ring is due to plate tectonics and the merger of the Pacific plate with other surrounding plates, which creates faults and seismic activity (especially Alaska, Japan, Oceania, and the west coasts of North and South America), along with volcanic mountain ranges such as the Cascades of the U.S. Pacific Northwest and the Andes of South America.

How many active volcanoes are there in the world?

There are about 1,500 active volcanoes around the world. Most are located in the Ring of Fire surrounding the Pacific Ocean. About one-tenth of the world's active volcanoes are located in the United States. A volcano is considered active if it has erupted in the last 10,000 years.

What are some of the world's most active volcanoes, in terms of numbers of years of eruptions?

The volcanoes that have been active the most number of years include Mt. Etna in Italy (3,500 years), Mt. Stromboli in Italy (2,000 years), and Mt. Yasur in Vanuatu (800 years).

Lava erupts from a volcano. Liquid rock, when below the Earth's crust, is called magma.

The ruins of Pompeii, the ancient city destroyed in 79 C.E. by the eruption of Mt. Vesuvius, can still be visited by tourists near Naples, Italy (photo by Paul A. Tucci).

Where are the active volcanoes in the United States?

Washington, Oregon, and California have many potentially active volcanoes. The most recent eruption in the United States was that of Mt. St. Helens in southern Washington state in 1980. Other volcanoes in the region, such as Mt. Shasta, Lassen, Rainier, and Hood could erupt with little warning.

What is the difference between magma and lava?

Magma is hot, liquefied rock that lies underneath the surface of the Earth. When magma erupts or flows from a volcano onto the Earth's surface, it becomes lava. There is no difference in substance; only the name changes.

How was Pompeii destroyed?

In the year 79 C.E., the volcano Mt. Vesuvius erupted and buried the ancient Roman town of Pompeii under 20 feet (6 meters) of lava and ash. Pompeii is famous because excavations of the city, which began in 1748 and continue to this day, provide an excellent look at Roman life at the beginning of the millennium. The covering of the city by debris preserved not only the places where people last stood but also paintings, art, and many other artifacts. The nearby city of Herculaneum also was perfectly preserved. Although a much smaller version of Pompeii, it contains some of the best art, architecture, and examples of daily life in Roman times and is only 20 minutes away from Pompeii.