Wednesday, April 21, 2010
Eyjafjallajökull(read AY-yah-fyah-lah-YOH-kuul), an Icelandic volcano, which has lied dormant for 200 years, has erupted, ripping a one km-long fissure in a field of ice on 20th March 2010.
Anyway the picture shows lightning, resulted from hot ashes ionizing the air...
The volcano near Eyjafjallajoekull glacier began to erupt just after midnight, sending lava a hundred metres high.
Taken from wiki:
"The plume of ash from a later ongoing eruption beginning on 14 April 2010 led to widespread disruption of air travel in Europe from 15 April, grounding planes and affecting the travel plans of millions of passengers worldwide. The aftermath of the 2010 Eyjafjallajökull eruptions adversely affected travel around the world."
Here we can see how volcanoes around the world can easily affect the lives of many. Perhaps one of the most popular stories about volcano is that it was responsible for the extinction of dinosaurs.
Well it was said that one of the bad volcanoes erupted and sent thousands of cubic meters of ashes onto the sky, and thus covering sunlight from reaching the surface of the earth. Plants couldn't undergo photosynthesis and died off, followed by the herbivores, and then the carnivores. Make sense.
Well I don't think that it is entirely true. There are also theories about asteroids that smashed into our planet and brought destruction to the dinosaurs.
These are the pictures of the crater in Arizona, created by a nickel-iron meteorite about 50 meters in diameter(olympic swimming pool length)that landed on our planet some 40,000 years back.
Another example of bad-ass-volcano is the Pinatubo Volcano of the Philippines
In June 1991, after more than four centuries of slumber, Pinatubo Volcano in the Philippines erupted so violently that more than 5 billion cubic meters of ash and pyroclastic debris(hot ashes, gas, and rocks, in case you don't know =P) were ejected from its fiery bowels producing eruption columns 18 kilometers wide at the base and heights reaching up to 30 kilometers above the volcano’s vent.
For months, the ejected volcanic materials remained suspended in the atmosphere where the winds dispersed them to envelope the earth, reaching as far as Russia and North America. This phenomenon caused the world’s temperature to fall by an average of 1 degree Celsius.
Next in line is Lake Toba in Indonesia, in Malay we call it Danau Toba.
It is not as innocent as it seems. Several thousand years ago (roughly 74000) it was actually an active volcano. If still active today, it would be considered as the MOST MASSIVE VOLCANO ever.
The Toba supereruption is recognized as one of Earth's largest known eruptions. The related catastrophe theory holds that this supervolcanic event plunged the planet into a 6 to 10 year volcanic winter, where volcanic ashes covered the earth and blocking sunlight, and thus reducing the temperature of the earth. This resulted in the world's human population being reduced to 10,000 or even a mere 1,000 breeding pairs.
There was evidence being discovered in virgin forests in India and the Greenland ice core, where researchers found clues of massive climate change during the time of the Toba Supereruption, which hint that the effect of the eruption went as far as India and Greenland~! impressive ashes...It is however, inactive today so we do not have to worry about another supermassive eruption. There are, however, other active volcanoes, though smaller, still pose potential threats to our lives. How, you may ask... you can simply run off cuz the lava flows slowly right... well the volcanic ash is the most dangerous element in a volcanic eruption. Toxic gas threatens the old and the young, especially those with asthma.
Have you ever heard of the ancient Italian city called Pompeii? It is the perfect example of volcano-destroyed-city. Pompeii was a large and thriving city that was destroyed along with Hercule....err... Herculaneum~ when a volcano named Mt. Vesuvius erupted in AD 79, killing many of the city's inhabitants and leaving behind a perfectly preserved example of ancient life in the Mediterranean.
This is a dog chained outside the house during the eruption. Completely covered by the hot ashes and died in plastered form.
Human inhaled the poisonous gases and burnt by the hot ashes.. died in plastered form
This is actually what they found during excavation, human covered by ashes..
One of the witness wrote that the cloud after a time rushing down the flanks of the mountain and covering everything around it, including the surrounding sea. This is known today as a pyroclastic flow, which is a cloud of superheated gas, ash and rock that erupts from a volcano.
Geologists have used the magnetic characteristics of over 200 volcanic rocks and pieces of debris found in Pompeii to estimate the temperature of this pyroclastic flow. Most of the materials analyzed experienced temperatures between 240 °C and 340 °C. This suggests that the ash cloud had a temperature of 850 °C when emerging from the mouth of Vesuvius, but had cooled to below 350 °C by the time it reached the city.
Nevertheless, volcanoes are part of an important cycle of nature. Islands around the world are results of underwater volcanoes that erupted, sending miles of lava that eventually emerges from the surface of the sea to form island.
Volcanoes are also responsible in keeping the temperature of our planet in check, just in case anthropogenic climate change sends our planet into a hot tub..
Anyway, the Toba, Arizona Crater, and the Pompeii stories are absorbed from national geographic channel(6-7 years ago), and the Iceland volcanic eruption is taken from http://news.yahoo.com/s/ap/eu_iceland_volcano, also courtesy of wikipedia. Images are courtesy of NatGeo and wikimedia...
(Haven't quote the source for several entries... Don't sue me~!)