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By the A.M. Costa Rica staff
There was a ripple of concern Tuesday after Volcan Turrialba emitted a
column of ash from the two openings in its crater.
The minor eruption came after several hours of small tremors that
scientific instruments picked up starting about 4:30 a.m.
This behavior is not unusual for the volcano east of San José,
and volcano experts said that ash was detected north of the volcano and
in parts of north San José.
Volcanologists have said they expect a major eruption from Turrialba
within the decade, and like the 1963 Irazú volcano eruption,
they expect several layers of ash on the metropolitan area. The major
involvement will be confined to some two to three kilometers around the
volcano, they predict. However, they point out that the volcano now
could also return to dormancy.
At the very least, Turrialba and the rest of Costa Rica's active
volcanoes show that humans are not fully in control.
In fact, turmoil seems to be the constant in the geological and
meteorological history of the world.
As Universidad Nacional scientists were keeping close eye on
Turrialba and even visiting the crater Tuesday, rescue workers and
emergency crews were seeking survivors in the U.S. state of Oklahoma
where a twister carved a path of destruction up to three kilometers
wide and 32 kilometers long through the town of Moore, a suburb of the
state capital, Oklahoma City. At least 24 are dead and at least 240 are
injured, according to wire service accounts.
Costa Rica has had its share of tornadoes, too, but mostly they strip
homes of their roofs and fell trees. Heredia, Hatillo and parts of the
north Pacific are most vulnerable.
The country is lucky that it does not see hurricanes, but the
long-range effects sometimes are devastating.
Honduras suffered through Hurricane Mitch in 1998 and counted nearly
5,600 dead and more than 8,000 missing with many thousands of injuries.
The 2008 hurricane season was hard on most of Central America including
Costa Rica. There was widespread damage.
The 2005 visit of Hurricane Katrina displayed another level of damage
in New Orleans, Louisiana, and adjacent areas.
Hurricanes are predictable and precautions can be taken. Not so
earthquakes. Costa Rica is in the ring of fire and has seen massive
destruction, ranging from the 1910 quake that leveled Cartago to the
Jan. 8, 2009, Cinchona quake that killed at least 24 and left scores
missing or injured north of Heredia Centro.
Of course, Haiti still is recovering from its massive quake, as are
many other areas of the world.
The only meteor or comet impact to earth in recent years has been the
Tunguska incident in Siberia in
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Observatorio Vulcanológico y
Sismológico
de Costa Rica
photo
This was the scene
at the volcano crater about 9
a.m. Tuesday.
1908, But there is a strong theory that
an impact 65 millions years ago at what is now Chicxulub in
Mexico helped dinosaurs go into extinction.
A new theory outlined only this week by a University of Cincinnati
academic says modern humans faced some kind of celestial disaster not
long ago.
Global-scale combustion caused by a comet scraping the planet’s
atmosphere or a meteorite slamming into its surface scorched the air,
melted bedrock and altered the course of Earth’s history, according to
Kenneth Tankersley, an assistant professor of anthropology and geology
at the University of Cincinnati, in a summary provided by the school.
Exactly what it was is unclear, but the event took place only 12,800
years ago. The professor gets his evidence from an unlikely place, an
excavation in a cave in Ohio where he found strong evidence of the
event.
Foremost among the findings were carbon spherules, according to a
university summary. These tiny bits of carbon are formed when
substances are burned at very high temperatures. The spherules exhibit
characteristics that indicate their origin, whether that’s from burning
coal, lightning strikes, forest fires or something more extreme.
Tankersley was quoted as saying that the ones in his study could only
have been formed from the combustion of rock.
He said that the
gigantic blast caused a perpetual winter that doomed the large
creatures that lived at that time: mammoths, cave bears and other Ice
Age beasts.
The spherules also were found at 17 other sites across four continents,
an estimated 10 million metric tons worth, further supporting the idea
that whatever changed Earth did so on a massive scale, the professor
reported. It’s unlikely that a wildfire or thunderstorm would leave a
geological calling card that immense, covering about 50 million square
kilometers, he said.
Modern humans lived at this time, and Tankersley said the race survived
because humans adapted to the catastrophe.
“Whether we want to admit it or not, we’re living right now in a period
of very rapid and profound global climate change. We’re also living in
a time of mass extinction,” Tankersley was quoted as saying. “So I
would argue that a lot of the lessons for surviving climate change are
actually in the past.”
A full report on his study is HERE!
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