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Title: 1. Intro to Geology


1
1. Intro to Geology 4. Earths Materials and
minerals 3. Rock Cycle and Rock types 4.
Structure of Earth 10. Hydrologic Cycle 8. Rock
Weathering Soils 6. Mass wasting 10. Streams
Running water 11. Groundwater 12 13. Glaciers
Deserts winds 14. Work of Ocean Shorelines 8.
Geologic time 17. Rock deformation 2 . Plate
Tectonics 16. Earthquakes, Tsunamis 17. Volcanoes
Hazards 18. Hawaii Geology 19 Geothermal
resources 20. Maui, Molokai, Lanai,
Kahoolawe 21. Kauai 22. Oahu
Earths Materials structure
External processes
Part II
External factors, Water resources
Where are we???
Part III
Internal Processes
Part IV
Hawaiian Islands Geology, Volcanic Processes,
Hazards, Geothermal Resources
2
Hawaii Born of Fire
Volcanic eruptions are one type of phenomena
that have shaped the Earth over the past four
billion years. The products of the volcanic
eruptions are creation of more land and islands
in the deep open sea. Hawaiian Islands are one
example of active volcanic processes. However,
there is still much to learn about how Hawaiian
volcanoes erupt and how island develops from the
ocean floor. The history of the volcanic islands
of Hawaii and the land formed by the volcanoes is
very contrasting and\mysterious.
3
Volcanic Air Pollution
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8
KILAUEA'S FUMES OVER HAWAII A CONCERN LONG-TERM
EFFECTS ON HEALTH, CROPS, BUSINESS CONCERN
RESIDENTS
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  • Vog Volcanic fog safety tips
  • Stay indoors and use an air conditioner, if
    available.
  • Do not smoke and avoid second-hand smoke.
  • Limit physical exertion.
  • Drink plenty of fluids to loosen mucus. Warm
    beverages seem to work best.
  • If you take medications, make sure you have an
    adequate supply and keep them readily available
    in a convenient place.
  • Contact your physician as soon as any respiratory
    problem develops.
  • While these recommendations are intended
    primarily for persons having respiratory or
    chronic lung disease, they are also useful for
    healthy persons during vog episodes.
  • To obtain additional information on respiratory
    health, contact your personal physician or the
    American Lung Association of Hawaii at (808)
    537-5966.

12
So-called vog, or volcanic fog, forms when
sulfur dioxide gas reacts with sunlight, oxygen,
dust particles and water in the air. Tiny
droplets known as sulfate aerosols are created,
along with sulfuric acid and other
substances. Elevated levels of sulfur dioxide gas
could cause breathing problems, especially among
those with respiratory conditions such as asthma,
emphysema and bronch
13
Halau makes offering to Pele at Kilauea Volcano
lookout Dancers with Halau Ka Liko Pua O
Kalaniakea, under the direction of Kumu Kapua
Dalire-Moe danced and chanted to pay their
respects to Pele on April 2, 2008. Volcanic fumes
spewed from Halemaumau in the background. After
the halau danced and chanted, they threw all
their leis into the crater, returning them back
to the earth
14
L A Z E Lava Haze
15
Air Pollution
Dispersion and Air Quality Forecasting
                                                                                                                                         
16
Vog Spreads over Hawaii Hotspot taking
Inter-Island trips
17
Located in the Central Pacific, just south of the
Tropic of Cancer and east of the International
Date Line, the islands of Hawaii enjoy a
tropical climate. The general climate of the
islands features moderate temperature from the
high 70s to the mid 80s (degrees Fahrenheit)
throughout the year. The islands are also
subjected to winds generally from the northeast
and localized rainfall storms.
18
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19
Chemicals and Ingredients of the Volcanic
Eruptions determine the Health Risks
Dispersion and Air Quality Forecasting
20
WHAT IS AIR POLLUTION
Definition Chemical, physical or biological
agents that alter the natural characteristics
of the Earths atmosphere
Examples Chemical Polycyclicaromatic
hydrocarbons (PAH) Persistent Organic
Pollutants (POPs) Physical Particulate
matter (PM), nuclear radiation Biological
Pollen, mold, germ warfare
21
SOURCES OF AIR POLLUTION
Human activities Manufacturing, trade
warfare Fuel power production Agricultural
production burning Transportation Household
activities waste disposal Construction Natura
l? Volcanic eruptions, wildlife emissions,
dust, wildfires, radiation
22
Air Pollution Natural Pollution, Volcanic Air
Pollution Types of Contamination Gases, Vapors,
Aerosols, Particulates, Volcanic Ash Public
Health- How does air pollution affect me? Air
Quality Index More Information All around the
earth there is a thick blanket of air called the
atmosphere. Air, like other gases, does not have
a fixed shape. It spreads out to fill any
available space so nothing is really empty. But
air cannot escape from the atmosphere as the
force of gravity keeps it from floating away from
the earth.
23
Ozone layer
Volcano Smoke Particles
24
Volcanic degassing
vog
Long-lasting Eruption of Kilauea Volcano,
HawaiiLeads to Volcanic-Air Pollution of
volcanic smoke particles
The volcanic smog--or vog, as it is
called--contains sulfur dioxide, which turns
rainwater acidic and causes respiratory health
problems.
25
Vog may pose health hazard
26
Volcanic Air PollutionA Hazard in Hawaii When
Lava Meets the Sea Lava Haze or Laze Air
Pollution
Pahoehoe lava enters sea. Extreme heat from lava
entering the sea rapidly boils and vaporizes
seawater, leading to a series of chemical
reactions. The boiling and reactions produce a
large white plume, locally known as lava haze or
laze, which contains a mixture of hydrochloric
acid (HCl) and concentrated seawater.
27
Avoid standing beneath a laze plume.Dense laze
plumes contain as much as 10-15 parts per million
of hydrochloric acid. These values drop off
sharply as the plume moves away from the lava
entry areas. During along-shore or on-shore
winds, this plume produces acid rain that may
fall on people and land along the coast. This
rain (pH 1.5 to 2), often more acidic that lime
juice or stomach acid, is very corrosive to the
skin and clothing. Visitors to the lava entry
areas should avoid standing directly in, under,
or downwind of the laze plume. \
28
Much is still unknown about vog's composition and
its effects on health. On the Island of Hawaii,
the trade winds (blue arrows) blow the vog from
its main source on the volcano (white plume) to
the southwest, where wind patterns send it up the
island's Kona coast. Here, it becomes trapped by
daytime (onshore) and nighttime (offshore) sea
breezes (double-headed arrows). In contrast, when
light "kona" winds (red arrows) blow, much of the
vog is concentrated on the eastern side of the
island, but some can even reach Oahu, more than
200 miles to the northwest.

29
Current ConditionsLast Updated  04/07/2007    1
045 AM HST  Sulfur Dioxide   Good Moderate  Unhea
lthy
GAS ADVISORY SYSTEM HELPS ALERT PEOPLE OF HAWAII
due to Volcano Smoke Particles
SO2 gas plume crosses road near Halemaumau and
low on Chain of Craters Road. Sensitive
individuals should limit exposure in these areas.
30
  • The hydrochloric acid (HCl) comes from the
    breakdown of seawater-derived chlorides during
    sudden boiling. Because the lava is largely
    degassed by the time it reaches the sea, any HCL
    coming from it is insignificant by comparison.
    Analyzed samples of the plume show that is is a
    brine with a salinity of about 2.3 times that of
    seawater and a pH of 1.5-2.0.
  • Key seawater chloride breakdown reactions that
    produce HCl gas
  • MgCl2 (sea salt) H2O (steam) MgO (periclase)
    2HCl (HCl gas) 
  • 2 NaCl (sea salt) H2O (steam) Na2O (sodium
    oxide) 2 HCL (HCl gas) 
  • CaCl2 (sea salt) H2O (steam) CaO (lime) 2
    HCL (HCl gas)

31
Volcanic Air PollutionA Hazard in Hawaii
Health officials have warned people with
asthma, bronchitis, emphysema, and allergies to
stay indoors where there is air-conditioning or
filtered air, to avoid strenuous exercise, and to
drink lots of water. The vog can also affect
children and the elderly. http//pubs.usgs.gov/fs
/fs169-97/ Noxious sulfur dioxide gas and other
pollutants emitted from Kilauea Volcano on the
Island of Hawaii react with oxygen and
atmospheric moisture to produce volcanic smog
(vog) and acid rain. Vog poses a health hazard by
aggravating preexisting respiratory ailments, and
acid rain damages crops and can leach lead into
household water supplies. Much is still unknown
about vog's composition and its effects on
health. The U.S. Geological Survey's Hawaiian
Volcano Observatory is closely monitoring gas
emissions from Kilauea and working with health
professionals and local officials to better
understand volcanic air pollution and to enhance
public awareness of this hazard.
32
Air pollution Pollution usually refers to the
presence of substances that are either present in
the environment where it doesn't belong or at
levels greater than it should be. Air pollution
is caused by any undesirable substance, which
enters the atmosphere. Air pollution is a major
problem in modern society. Even though air
pollution is usually a greater problem in cities,
pollutants contaminate air everywhere. These
substances include various gases and tiny
particles, or particulates that can harm human
health and damage the environment. They may be
gases, liquids, or solids. Many pollutants are
given off into the air as a result of human
behavior. Pollution occurs on different levels
personal, national, and global. Some pollutants
come from natural sources. Forest fires emit
particulates, gases, and VOCs (Volatile organic
compounds and substances that vaporize into the
atmosphere) Ultra-fine dust particles created by
soil erosion when water and weather loosen layers
of soil, increase airborne particulate levels.
Volcanoes spew out sulfur dioxide and large
amounts of pulverized lava rock known as volcanic
ash and volcanic smoke particles.
33
Passive
Eruptive
           Which emission source is larger? Passive or Eruptive?
Reventador (Ecuador)
Nyiragongo (DR Congo)
  • No eruption of magma
  • Long-lived (weeks-centuries)
  • Low altitude - tropospheric (lt5 km)
  • Environmental/health hazard
  • Climate impacts poorly understood
  • Poorly quantified
  • Magma erupted (ash)
  • Short-lived (hours-days)
  • High altitude - stratospheric (lt40 km)
  • Aviation hazard (ash)
  • Global climate effects possible
  • Well quantified (TOMS)

34
Steam rises under a forbidding sky, as lava from
the Piton de la Fournaise volcano drains into the
Indian Ocean. The 2,632 meters (8,635 feet)
mount, on Reunion Island, has erupted three times
this year. The latest phase began on 2 April. The
island, a French territory, neighbors Mauritius.
35
  • Natural Background Aerosol
  • Stratospheric and tropospheric aerosol
  • Stratospheric aerosol
  • 11-50 km
  • Formation of sulfuric acid droplets by
    gas-to-particle conversion of SO2 injected into
    the stratosphere by major volcanic eruptions
  • Tropospheric aerosol
  • lt11 km
  • Direct emissions from natural sources desert,
    ocean, and vegetations
  • Gas-to-particle formation

Eruption of Mt. Pinatubo (in the Philippines) in
1991
Do You Know
During the eruption of Mt. Pinatubo, 14-20 Tg (1
Tg 106 tons) of SO2 was injected into the
stratosphere, causing the aerosol concentration
to increase from 2-5 µg/m3 to 20-100 µg/m3
Does tropospheric aerosol concentration vary with
altitude? Why?
36
Net solar radiation at Mauna Loa Observatory,
relative to 1958, showing the effects of major
volcanic eruptions. Annual variations are due to
transport of Asian dust and air pollution to
Hawaii www.research.noaa.gov/climate/t_greenhouse.
html
37
Volcanic Gas Emissions Volcanic Smoke Particles
Vog
38
Contour map of volcanic air pollution in the Kau
District, Big Island of Hawai'i, during September
2003. Eruption at Kilauea Volcano produces a
visible plume from the eruption vent and
degassing from the summit.
39
Hawaiian residents who live downwind from the
long-active Kilauea volcano may have elevated
risks of adverse health conditions because of
high levels of sulfur dioxide and aerosol
particulates that drift downwind, Eye
irritation Headache Upper respiratory Irritation N
ausea, dizziness Fatigue, lethargy Sore/dry
throat Odor Memory impairment
40
Many residents on the island of Hawaii depend on
rainwater collected by rooftop catchment systems
for drinking water. The continuous release of
volcanic gases, especially sulfur dioxide, causes
rainwater to become acidic downwind of Kilauea's
erupting vents. When it falls on roofs, this acid
rain leaches lead from roofing nails and paint.
The lead-contaminated rainwater then fills the
water catchment tanks, creating a health hazard.
Vog and acid rain affect water quality
41
Volcano Tectonic StyleTemperature Kilauea SummitHot Spot1170C Erta AleDivergent Plate1130C MomotomboConvergent Plate820C
Water Vapor H20 37.1 77.2 97.1
Carbon Dioxide C02 48.9 11.3 1.44
Sulfur Dioxide S02 11.8 8.34 0.50
Hydrogen H2 0.49 1.39 0.70
Carbon Monooxide CO 1.51 0.44 0.01
Hydrogen Sulfide H2S 0.04 0.68 0.23
Hydrochloric Acid HCl 0.08 0.42 2.89
Hydrofluoric Acid HF --- --- 0.26

Examples of volcanic gas compositions, in volume
percent concentrations (from Symonds et. al.,
1994)
42
A volcanic eruption may send ash and sulfate gas
high into the atmosphere. The sulfate may combine
with water to produce tiny droplets (aerosols) of
sulfuric acid, which reflect sunlight back into
space. Large eruptions reach the middle
stratosphere (19 miles or 30 kilometers high). At
this altitude, the aerosols can spread around the
world.
43
The Earth's atmosphere is made up mostly of
nitrogen (78) and oxygen (21), with a small
amount of "trace gases" (1) mixed in. But, that
tiny percentage of trace gases - such as carbon
dioxide, ozone, methane, and carbon monoxide -
contribute in a big way to changes in the Earth's
climate. Such trace gases, also called greenhouse
gases, allow energy from the sun (known as
shortwave radiation) to reach the earth's
surface, but absorb energy emitted from the earth
(known as longwave radiation) this affects the
surface energy balance of the planet by warming
the atmosphere directly above it resulting in
long-term changes to global climate. Although a
greenhouse also works by trapping energy from the
sun, the physics is different. The roof of a
greenhouse is a slab of glass that traps
radiation emitted from the ground which prevents
convection (i.e. rising hot air) from allowing
heat to escape. The atmospheric greenhouse is
based on certain molecules (e.g. carbon dioxide)
absorbing radiation at particular wavelengths
(such as that emitted from the ground) and
reemitting a portion back to the ground. Although
an excess of greenhouse gas results in global
warming, naturally occurring greenhouse gases are
beneficial in keeping our planet at a comfortable
temperature.
44
Aerosols Small particles in the atmosphere -
from smoke, dust, manufacturing, and other
sources - can affect how the Earth system
behaves. For example, aerosols can absorb and
scatter radiation, which can cause either warming
or cooling of the atmosphere. They also are
important to the formation and behavior of
clouds, and can influence the water cycle and the
Earth's radiative balance.
45
Sierra Negra (Galapagos Is) eruption - October,
2005
27 Oct 2005
22 Oct 2005
  • Effusive eruption
  • Oct 22 - Nov 1, 2005

23 Oct 2005
46
Topography
  • At night, cold, dense surface air drains downhill
    into low-lying areas, making them susceptible to
    strong temperature inversions
  • Hills and mountains can block flow (like Mauna
    Loa)
  • Sea breezes can trap pollution in its vertical
    circulation (East Maui)

47
A volcanic eruption may send ash and sulfuric
acid (SO2) into the atmosphere, which increases
planetary reflectivity causing atmospheric
cooling. Over time precipitation will remove
these aerosols from the atmosphere. Volcanic
eruptions can have a worldwide impact. A massive
volcanic eruption can cool the Earth for one or
two years. The 1982 El Chichon eruption and the
1991 Pinatubo eruption caused the globally
averaged surface temperature to cool less than
1F
48
Acid Rain
  • Note that clean rain is naturally acidic (pH of
    5.6) due to carbon dioxide in the atmosphere
    dissolving in the water to create carbonic acid
    H2O CO2 gt H2CO3
  • Other acids are created when pollution aerosols
    dissolve in water
  • Important acids created due to mans activities
    are sulfuric acid and nitric acid

49
Sulfuric Acid
  • Sulfur dioxide dissolves in water to create a
    weak acid, sulfurous acid SO2 H2O gt
    H2SO3
  • Sulfurous acid then can react with oxygen to
    create sulfuric acid H2SO3 O2 gt H2SO4
  • Once again, sulfur dioxide is emitted primarily
    by coal-burning power plants

50
Nitric Acid
  • Nitric acid is created when nitric oxide (NO)
    oxidizes, yielding nitrogen dioxide (NO2). The
    nitrogen dioxide then dissolves in water creating
    nitric acid (HNO3) and nitrous acid (HNO2)
  • 2NO2 H2Ogt HNO3 HNO3
  • High temperature combustion, such as automobiles,
    produced the nitric oxide that began this process

51
Acid Rain Consequences
  • Crop and forest damage
  • Increase in acidity for lakes, rivers
  • Death of fish and wildlife
  • Weathering of monuments and buildings
  • Health impacts for those prone to respiratory
    ailments

52
Particulate Pollutants
53
  • Sources of Atmospheric Aerosol

TABLE 1 Sources and Estimates of Global Emissions of Atmospheric Aerosols (Data from W.C. Hinds, Aerosol Technology, 2nd Edition, Wiley Interscience) TABLE 1 Sources and Estimates of Global Emissions of Atmospheric Aerosols (Data from W.C. Hinds, Aerosol Technology, 2nd Edition, Wiley Interscience) TABLE 1 Sources and Estimates of Global Emissions of Atmospheric Aerosols (Data from W.C. Hinds, Aerosol Technology, 2nd Edition, Wiley Interscience)
Source Amount, Tg/yr 106 metric tons/yr Amount, Tg/yr 106 metric tons/yr
Source Range Best Estimate
Natural    
Soil dust 1000 - 3000 1500
Sea salt 1000 - 10000 1300
Botanical debris 26 - 80 50
Volcanic dust 4 - 10000 30
Forest fires 3 - 150 20
Gas-to-particle conversion 100 - 260 180
Photochemical 40 - 200 60
Total for natural sources 2200 - 24000 3100
Anthropogenic    
Direct emissions 50 - 160 120
Gas-to-particle conversion 260 - 460 330
Photochemical 5 - 25 10
Total for anthropogenic sources 320 - 640 460
           Which emission source is larger? Natural or anthropogenic?
54
The Air Quality Index is a tool used by EPA and
other agencies to provide the public with timely
and easy-to-understand information on local air
quality and whether air pollution levels pose a
health concern. The AQI tells the public how
clean the air is and whether or not they should
be concerned for their health. The AQI is focused
on health effects that can happen within a few
hours or days after breathing polluted air .
55
Toxins in the Air
  • As a result, EPA is now using an exposure
    assessment methodology that measures all the
    exposures to toxics regardless of media (e.g.,
    air, water, land).

56
What Is Exposure Assessment?
  • Scientists and government officials use a
    four-step process called risk assessment to
    estimate people's increased risk of health
    problems as a result of exposure to a toxic air
    pollutant.

57
THE 4-STEP EXPOSURE ASSESSMENT
58
Hawaii Volcanoes National Park is perhaps the
only place on earth where visitors arrive in
continuous carloads to peer at volcanic
landscapes, erupting ashy craters, calderas,
cones, plumes of gas, and skeletons of trees and
to clamber over sharp rock, desperate to see
lava. Despite many posted warnings, people in
open-toed sandals and shorts eagerly trot along
newly hardened, still hot lava to peek through a
sudden opening and catch a glimpse of the red
flow. The desire to be as close as possible to
this force of nature has cost five people their
lives in the past decade because they ignored
warnings either about lava hazards or about
medical conditions that can be aggravated by
sulfuric fumes. At the same time, however,
Hawaiian volcanoes are, as volcanoes go, gentle
giants ones--so if you are going lava hunting,
this is the place to do it. Hawaiian lava here is
more fluid than most and contains less gas, so it
is less explosive and gives rise to what are
called shield volcanoes because of their sloping
profiles. landscape, a battlefield of burned
trees and buried houses--although a few
structures stand stranded in small patches of
rain forest, spared by the flow. Puu Oo
destroyed the Royal Gardens community here
between 1983 and 1986 and covered part of the
park's Chain of Craters Road. From the air it is
easy to appreciate the power and reach of the
volcano, the primal force shaping this island,
creating new land (about 600 acres' worth so
far), incinerating everything in its path
59
Gas composition monitor the composition of gases
that are continually vented from the volcano, and
note some unique changes in the gas composition
have correlated with eruptions that followed
60
Air mass moves inAn air mass moves toward a
mountain. This air mass holds water vapor that
has evaporated from an ocean
61
Air mass forced upward The slope of the mountain
forces the air mass upward. .As the air moves
higher, it becomes less dense. The reason is
that, at higher elevations, there is less air
above to push down on the air mass. This decrease
in air pressure causes the air to expand. As it
expands, it cools. This process, called adiabatic
cooling, typically results in a cooling of about
1C per 100 meter ( 5.5F for every 1,000 feet).
62
Clouds form As the air is forced higher, it
cools even more. When it reaches its dew point --
the temperature at which water vapor in the air
becomes saturatedwater molecules within the air
start to condense, forming water droplets. These
droplets are visible as clouds.
63
Rain, sleet, and snow The air continues to cool
as it rises, but not as fast as before because
condensation heats the air. As it cools, more
water drops form. When they get large enough,
they fall to the Earth in the form of rain,
sleet, or snow. This is why the windward side of
a mountain is usually wetter than its leeward
side.
64
Over the summit After the air mass passes over
the mountain's summit, it begins to descend. Just
as the air cooled as it became less dense, it now
begins to warm as it becomes denser at lower
elevationsagain, at a rate of about 5.5F for
every 1,000 feet. This process is called
adiabatic warming.In addition to becoming denser
and warmer, the air's relative humidity decreases
as it descends. Relative humidity is the total
amount of water vapor in the air, measured as a
percentage of water vapor the air can hold at a
given temperature.
65
Rain shadow The warmed air mass, which lost most
of its water content on the other side of the
mountain, warms quickly as it descends. Because
heat was added to the air mass when, on the other
side of the mountain, its water vapor condensed,
it can be much warmer when it reaches the base of
the mountainas much as 50F warmer than it was
before it started its ascent. The lack of
moisture, and rain, on the leeward side of a
mountain is known as its "rain shadow."
66
For those who live on or near mountains, a change
of climate can be just a short walk away. That's
because mountains create their own
microclimatesareas in which the climate differs
from the prevailing climate. Take Mauna Loa,
Mauna Kea or Haleakala. These volcanoes in Hawaii
have microclimates that range from scorching at
the base to frigid at the summit. (For a look at
the mountain's six ecological zones, see
Figures.) The flow of air masses over these
volcanoes and other mountains also influences
microclimates, often causing wet (or snowy)
weather on one side and a dry, clear climate on
the other.
67
The volcanic smog--or vog, as it is
called--contains sulfur dioxide, which turns
rainwater acidic and causes respiratory health
problems.
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Flank eruption
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Vog, volcanic smog, is a concern to the residents
of the Big Island of Hawai'i because of the
possible harm it is doing to their health,
agriculture, and the tourist industry.
(Monastersky, 1995) Sore throats, headaches,
allergies, and bronchitis have been blamed as
some of the health hazards of vog
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73
VOG Volcanic Smoke Fog) lava slowly comes out,
but so does smoke containing sulfur, mercury, and
arsenic. 80 of the time the NE Tradewinds blow
and keep this VOG (volcanic fog) off Maui. When
the trades don't blow, the VOG drifts over Hawaii
and Maui, and it gets hazy
74
During prevailing trade wind conditions, the
nearly constant stream of volcanic smog (vog)
produced by Kilauea Volcano on the Island of
Hawaii is blown to the southwest and west
(satellite image shows increasing amounts of vog
aerosol particles in yellow, orange, and red,
respectively) traces have been detected as far
away as Johnston Island, 1,000 miles to the
southwest. On the Island of Hawaii, the trade
winds (blue arrows) blow the vog from its main
source on the volcano (white plume) to the
southwest, where wind patterns send it up the
island's Kona coast. Here, it becomes trapped by
daytime (onshore) and nighttime (offshore) sea
breezes (double-headed arrows). In contrast, when
light "kona" winds (red arrows) blow, much of the
vog is concentrated on the eastern side of the
island, but some can even reach Oahu, more than
200 miles to the northwest. (The names of the
five volcanoes that make up the Island of Hawaii
are shown in yellow. National Oceanic and
Atmospheric Administration (NOAA) satellite image
processed by John Porter and collected by Pierre
Flament, University of Hawaii.)
75
VOG Volcanic Smoke Fog
76
HVO shows how scientists take temperature
readings in the volcano's crater to help them
predict how far below the surface the magma lies.
Molten lava from Kilauea Volcano frequently
flows through underground lava tubes to reach the
Pacific Ocean, where it vigorously reacts with
cold seawater to create large steam plumes laden
with hydrochloric acid (HCl). These plumes, known
as "laze", are another form of volcanic air
pollution and pose a local environmental hazard
along the Island of Hawaii's southeast coast and
southeastern Maui, especially to people who visit
these ocean-entry sites. Kilauea is the single
largest source of volcanic sulfur dioxide in the
world, emitting as much as 1,800 tons of the gas
a day, and 40,000 truckloads of volcanic
materials on the land.
77
When a volcanic erupts, sulfur dioxide within the
molten rock is converted to sulfuric acid. The
resulting plume is known as vog (volcanic fog).
Gases are also produced at the ocean. When the
lava enters the ocean, hydochloric acid is
produced - called laze (lava haze). Both of these
gases can contain particulate matter, such as
volcanic glass or trace metals. Vog and laze are
carried by winds across the county. The impacts
include obscured views lower agricultural
yields for certain crops adverse health effects
for people with respiratory or heart conditions
and acidified rainwater catchment tanks (which,
in turn, produces a secondary hazard of leached
lead in local water supplies).
78
The goals of the Lung Assessment during Volcanic
Activity study, LAVA for short, include Teaching
residents research skills enabling them to
participate in their environmental health and
safety. Assessing the community's exposure to
vog over the last 10 years, based on historical
records of weather patterns and volcanic
emissions. Measuring current acidity and amount
of particles small enough to breathe. Studying
the respiratory systems and lung functions of
children across the island who have lived their
entire lives with vog. Studying the lung growth
and health of these children five areas on the
Big Island the Kona Coast (west Hawaii), Hilo
(east Hawaii), Kau, (on Hawaiis south coast),
Waimea and the Kohala Coast (on the northern tip
of the island). LAVA project Elizabeth Tam, a
pulmonologist at the University of Hawaii's John
A. Burns School of Medicine on Oahu
79
Mt Ruapehu Crater Lake Lahar Threat Response -
Image of Whangaehu Valley, March 18, 2007.
80
What is a lahar? Lahar is an Indonesian word that
refers to a rapidly flowing mixture of rock
debris and water (other than normal water flows)
from a volcano. Large lahars can present a
significant natural hazard. When they overflow
their channels they can destroy, erode or bury
obstacles in their path. There are various kinds
of lahar. A debris flow lahar contains
large amounts of sediment (more than 60 of
volume) of varying size (from small particles to
boulders) and flows like a slurry. A
hyperconcentrated flow lahar contains less
sediment (mainly sand-sized particles or
smaller) and flows more like water. Management
precautions for the predicted Crater Lake lahar
are based on a debris flow lahar.
81
A train passes over a bridge over the Whangaehu
River at the scene of the historic Tangiwai Rail
disaster after a mud flow from the crater lake of
Mount Ruapehu, in the central North Island, New
Zealand, Sunday, March 18, 2007. A potentially
lethal mix of mud, acidic water and rocks tore
down the slope of New Zealand\'s Mount Ruapehu on
Sunday, emergency officials said, but there was
no immediate threat to life. (AP Photo/NZPA,
Stephen Barker)
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