Clouds as Warning?

I love clouds. Especially ones that look like a storm. But did you know that clouds can talk?

Lenticular clouds often form near or above Mt. Rainier (pictured). Lenticular clouds (clouds shaped like lentils) form because a mountain reaches up into the atmosphere so high - in the case of Mt. Rainier that is 14,410 feet. Its peak pokes up into the sky so high that air is forced to rise above it, where the air is much cooler and often the mountain emits a bit of warmth near the crest. Clouds begin to form that are shaped like " flying saucers" because of the shape of the mountain peak and the winds rising above. Lenticular clouds are indicators for a change in weather, often a prelude to chinook winds (warm dry winds).

Clouds like these appeared over Mount St. Helens just one month prior to its May 1980 eruption. Was it a warning?

Clouds don't always warn people about volcanic activity. There are many other indicators of a waking volcano. Seismic activity (earthquakes and tremors) in the area warn geologists today about a waking or active volcano. NOVA has created a FLASH version of how seismic activity works. In this demonstration you can also see how seismic activity is recorded.

What can artifacts tell us?

Archeology (the study of human history through excavation and artifacts) can tell us things about how people lived, died and suffered. They tell what people liked, their hobbies and even sometimes their ideas. Sometimes another word for artifact is heirloom.

Artifacts can include simple household items, furniture, artwork and even human remains.

In Pompeii, the area covering the final surge cloud is so large, only one area of it has been excavated. No matter where archaeologists dig, they always find bodies. Many of the artifacts from Pompeii's central region have been uncovered, yet only a portion of the area is fully excavated. Researchers continue to study Pompeii because of how well preserved things are below the ash.

Every city, every family and every single person has belongings. When people die, when families die out, when cities go dormant, artifacts remain to tell others who those people were.

This picture is an artifact of Pompeii. It shows a fresco [painting done on wet plaster] found in the ruins of the city. The picture is one of the first ever to depict a literate female - a young girl poised with her pen and book in hand. Girls were not permitted to attend school but received their instruction at home. Many girls learned to read but never write - as these were two separate skills. The girl pictured here is shown able to do both. It is believed that Roman girls recieved more (and better) education at home than their Greek neighbors, allowing more opportunity for higher status at the time of a female's maturity; around the age of 13-14.

??--QUESTIONS: What sort of artifacts does your family treasure? Do you have a book, hankerchief or poem left behind by a grandparent or aunt? What type of artifacts interest you the most?


for more information about what artifacts can tell us visit one of these pages: Artifacts Tell Sad Tales (short article) or History Now (about how builders in NY City in 1991 uncovered a burial ground for slaves).

Teachers might also like these lesson plan ideas about Artifacts and the Culture of China or King Tut's Treasures.

Could this happen today?

Just because Pompeii was destroyed centuries ago doesn't mean it is an unlikely event these days. Many cities live in the shadow of a volcano or two - large cities - like Seattle, Washington, for one.

Seattle is near a volcano called Mt. Rainier. It is one of the loveliest mountain peaks in North America - much the same as Mount St. Helens was, which erupted in 1980. Both of these mountains are part of the Cascades Mountain range.

According to the USGS (United States Geological Service), Mt. Rainier (pictured here) is one of the most hazardous volcanoes in the United States, due not only to its regular activity, but also to its proximity to a populated area.

There is a geological observatory in Vancouver that monitors the seismic activity (underground earthquakes and movement) of mountains in this range.

Lahars (which are volcanic mud flows) are the biggest and most frequent danger to cities near Mt. Rainier these days. The USGS has a fantastic information page on Learning to Live with Volcanic Risk.

Existence proven: Excavations begin

When a discovery is made of an inscription to Pompeii (see movie clip), the world realized that Pompeii had not been a legend, but a real city. A man named Theorelli became responsible for uncovering the city of Pompeii. This pictures shows the House of the Fawn, in Pompeii.

This video, "Video: Pompeii: Discovery and Excavation" is owned by VastVideo and Encyclopedia Brittanica, for preservation of facts and artifacts of the city of Pompeii.

What can archaeology tell us?

Archeology (the study of human history through excavation and artifacts) can tell us things about how people lived, died and suffered. Scientists have learned a lot from digging up portions of Pompeii and Herculaneum (see video about archeology).

As visitors we were told that residents were killed by falling rock, but few of the bodies recovered show evidence of physical damage. Lava did not flow for more than a week after the eruption. Instead, the lava crystallized into a fine, glass pumice (4 meters of it). Most of the human remains recovered are completely in tact, showing little to no physical damage. Many bodies were preserved in pockets of air, so that we can see their positions at death. Positions of humans, dogs and horses show suffocation to be the primary cause of death (see movie clip).

Archeology tells us all this, and more.

The area covering the final surge cloud is so large, only one area of it has been excavated. No matter where archaeologists dig, they always find bodies, even far outside Pompeii. This suggests a large death toll. A total of 1044 bodies have been found in Pompeii, but archaeologists believe that 10 times that many died (over 10,000 people). That would mean that half the population of Pompeii died as a result of the Vesuvius eruption.

Plaster molds of bodies found in Pompeii show us how over 1000 people died (see movie clip). 3D MRI scanning gives us a better picture of who they were and their deaths.

Picture 1 shows the remains of the Macellum, also known as the covered market place.Picture 2 shows casts of human remains found in Pompeii.

all videos are courtesy of United Streaming and Discovery Education. The complete video can be viewed under a membership login at United Streaming. "Enduring Influence: Rome, Greece, and Byzantium" and also " Forensic Detectives: Archeology at Work."

Forensic Detectives: Archaeology at Work (55:37) This video contains 34 segments. Description: Remnants of the past tell remarkable stories about ancient cultures, civilizations, and cataclysmic events. Video segments explore the history of China, Peru, and Jerusalem, and examine the Earth’s magnetic poles. Spanning many locations and eras, this presentation invites students on a worldwide journey to study the forensic uses of archaeology and geology. © 2004 Discovery Channel School Grades: 6-8 Play Download My Content Assignment Quiz

Enduring Influence: Rome, Greece, and Byzantium (55:39) This video contains 12 segments. Description: Pompeii: Preserved in Time (32 min.)—Examines the final 24 hours for the people of this ancient Roman city before the catastrophic eruption of Vesuvius. Greece: One Out of Many (4 min.)—Traces how an assortment of city-states in the Aegean became one of the world’s most complex and influential cultures. The Rise of Rome’s Empire (5 min.)—Shows how Rome’s emperors swept away the old republic, created a vast empire, and came into conflict with a new religion, Christianity. Byzantium and Its Roman Ideals (5 min.)—Reviews the collapse of the Western Roman Empire and how its surviving Eastern empire kept alive its achievements and heritage. © 2005 Discovery Channel School Grades: 9-12 Play Download My Content Assignment Quiz

Dangers of Volcanic Ash

Many of the people in Pompeii died from volcanic ash. I wondered how ash could kill someone; couldn't they just leave if the ash became unbearable? That was before I understood the composition of the ash, and how it affects people and things.

When the ash is expelled from a volcano, it can form a cloud. This cloud can rise as a plume (composed of ash and steam) very high into the atmosphere, then fall (what goes up, must come down). Volcanic ash is hard and abrasive. Today it even causes scratches on airplane windows as ash is released from volocanic activity.

Example of what volcanic ash can do:
In 1989 there was an eruption at Mount Redoubt, a volcano in Alaska.

After this explosion a KLM Boeing 747 (flight 867) carrying 240 passengers unknowingly flew through an ash cloud at 26,000 feet. The pilot applied full power, hoping to climb above the plume. Instead, all four engines stopped. The plane dropped to an altitude of 13,000 feet before pilots were able to get the engines started again. The plane did land safely in Anchorage, but the cost repair to the plane was $80 MILLION. The cost was so high because all four engines had to be replaced.

It turns out that the engines were covered with glassy coatings - or resolidified melted ash. When full power was applied to the engines, they became hotter than the melting temperature of the ash, which then turned the ash into a sort of glass coating.

Today the airline industry has a standard procedure of reducing power if a plane comes in contact with volcanic ash plumes. That is, of course, assuming that the plane could not simply go around it.

Because volcanic ash does not dissolve, breathing it (especially over an extended period of time) can cause respiratory failure. The ash from Vesuvius covered a large area, not just Pompeii, but all the area surrounding it; in other words, Pompeii's escape route. This explains a little about how so many people died as a result of falling ash in Pompeii - suffocation -which also explains why the bodies uncovered were not damaged from falling rock.

(photograph shows an ash plume from Mt. Cleveland, Alaska, May 2006)


For more information on the modern-day dangers of vocanic ash, visit the ALPA Fact Sheet: Volcanic Ash Hazards to Airliners

Recovered Remains

Bodies disintigrated under the hot ash of Vesuvius's eruption, but the ash preserved pockets of air underneath the smoldering ash.

When excavations began, someone came up with the idea of pouring plaster into these pockets. What they got were perfectly formed molds of the bodies of people who died under that hot ash so long ago.

Weird, and a little creepy.

All sorts of bodies have been 'recreated' in this manner; those of men and women children, and even dogs.

Other Volcano Disasters

There have been many other volcanic disasters (click the chart at left). Some are famous. Others are more obscure, but no less devastating.

Akrotiri in the Santorini Islands, Greece - date uncertain (approx. 17th century BC). The Geology of Santorini is still under study.

Atlantis - a legend about a city during the time of Plato (9400 BC). Little is known if the city actually existed and was lost, or if it is only a legend, but many still speculate.

Krakatau (Krakatoa), Indonesia - 1883. The explosion was heard as far away as Perth, Australia (5000 km. away). 165 villages were destroyed and another 132 seriously damaged.

Mount Pelee, St. Pierre, West Indies - 1902. More than 29,000 people died.

Mount St. Helens, Washington - 1980. Somehow, people just didn't see this coming. Read the narrative of the disaster.

Nevado del Ruiz, Columbia - 1985. Killed more than 21,000 people. Considered the second most destructive volcanic eruption (just under Mt. Pelee) in the 20th century.


??--QUESTION: What do these, and others on the chart, have in common (besides being volcanoes and being destructive)? HINT: see an earlier post from the 3rd of Oct.

To find out more about volcanoes of the world, visit the USGS site on Noteable Volcanic Disasters.

For more information about the study of volcanoes, visit the Global Volcanism program.

Pliny's Escape Route

When refugees of Campania left Pompeii many of them fled to the ocean, not realizing that it, too, would be affected by the tremors of the erupting Vesuvius. Still, this route proved worthy and some people escaped death. One of those people is a young man name Pliny the Younger. Today we might call him Pliny, Jr.

Pliny lived in Pompeii with his family. When Vesuvius began its hostile action, Pliny the Younger and his mother decided to leave. Piny's uncle, Pliny the Elder, decided to stay in Pompeii.

This map shows how Pliny, Jr. and his mother escaped. His uncle, Pliny the Elder, was commander of a fleet of war ships at Misenum (see map). He decided to use his ships to rescue people close to the volcano.

Pliny the Younger did a thorough job of telling the details of their escape. To read more about this story, visit Mount Vesuvius.

What have we learned?

Although the eruption of Vesuvius on that warm August day in 79 A.D. took the lives of thousands of people, it has allowed us all to learn many things. Because of the way things were preserved beneath the ashes, we have a better idea of what life was like during that period of time in the Roman Empire.

Vesuvius and her hot ash has also taught geologists important facts about the behavior of volcanoes, as well as cues that nature sends prior to a catastrophic event. Pompeii and its fate has served city planners in the shadow of other volcanoes, helping them to design emergency systems, evacuation plans and a variety of other protective measures for people who live in the vicinity of a volcano.

Reconstruct Vesuvius

If you like science experiments then you will enjoy this; you can make your own volcano AND make it erupt. You can build these in class or at home with the right ingredients.

HOW TO MAKE AN ERUPTING VOLCANO

First, you need to make the model. You can make it out of clay, paper mache or salt dough. I like the salt dough best (like playdough). The recipe for salt dough is:

• 6 cups of flour
• 2 cups of salt
• 4 tablespoons of cooking oil
• 2 cups of warm water
• small soda or juice bottle (or a small paper cup)
• a box
• aluminum foil
• newspaper or disposable table cloth
• plastic plants, houses, people, etc (optional)
  

Mix the first four ingredients in the list together. The fun part is mixing this up with your hands. If you think you need more water, add ONLY a few drops at a time. Make sure all the ingredients are mixed together well.

You can add food coloring or you can paint it with poster paint once it dries.

Get a box from the supermarket and cut it down to only 3" high. Line the box with aluminum foil and place it on an old cookie sheet. Be sure to cover your work area. If you use newspaper, then you can just throw it and the mess away when you are done.

Shape the salt dough around a small plastic soda bottle to make a mountain.

The volcano can be made more realistic by building this mountain. Lava channels and vegetation can be built around the volcano.

The soda bottle acts as the chimney of the volcano. If you want to put small trees and bushes on the mountain, do it now before the salt dough dries. You can also add tiny houses or buildings to represent a town.

Let the dough dry thoroughly. You can put it in the oven at 200-250 degrees, but check it very often. The oven in NOT necessary, letting it dry over night works just fine.

When the dough is dry, you can paint it to look like a mountain.

Eruption Ingredients

• a funnel
• warm water
• dishwashing liquid (like Dawn or Palmolive)
• orange or red food coloring
• vinegar (white or apple cider)
• baking soda
  

Fill the bottle with warm water and red food coloring. Add 6 drops of liquid dishwashing detergent. With a dry funnel add 2 tablespoons of baking soda. Then slowly add vinegar to the bottle. The liquid will foam and flow down the sides of the mountain.

When you mix vinegar and baking soda together, it creates carbon dioxide. Carbon dioxide is the same gas that causes the lava to bubble and is produced during a volcanic eruption.

The Chemical Reaction
NaHCO3 + CH3COOH --> Na+ + H2O + CO2 + CH3COO-

Carbon dioxide is released, which creates the fizz.

For more ideas on reconstructing a volcano, visit Volcano World's Volcano Models

Ring of Fire

Volcanoes exist all over the globe, but there is one particular area where they are most prominent. That place is known as The Ring of Fire.

The Ring of Fire is located in the Pacific, along the rim of continents that encircle it. It is the shape of a horse shoe, is 25,000 miles long and borders the 'Pacific Plate.' This is the most concentrated place on the globe where volcanoes and earthquakes appear.

Seattle, Portland, San Francisco, Monterey, Los Angeles, Baja, Central America, Chile and Peru are all directly located on the eastern side of the "Ring of Fire." 90% of the world's earthquakes and 81% of the world's largest earthquakes occur along the Ring of Fire.

The Ring of Fire is a direct consequence of plate tectonics and the movement and collisions of crustal plates. Earth's sphere is made of plates which fit together like a puzzle. There are ten major plates in all (plus some minor ones), and they sometimes push against one another or even pull apart, causing earthquakes, tsunamis and volcanic activity.

The second most seismic region of the Earth is the Alpide Belt. This is home to 5­6% of the world's earthquakes and 17% of the world's largest earthquakes. This just happens to be the location of Vesuvius, along the region of the Mediterranean.

Vesuvius told us much about what happens during an eruption, and what can happen if cities within its vicinity lack precautionary methods of protection and evacuation.

??--QUESTIONS: In which belt region or plate region do you live? Are earthquakes common in your area? How do you deal with them?

(photograph shows lightning during the 1982 Galunggung eruption in Java, Indonesia - also located on the Ring of Fire)

for more information about the Ring of Fire, visit Crystalinks Pacific Ring of Fire information page. This page contains maps, diagrams and links with further explanation.