changing Earth's surface affects society through landslides, land
subsidence, floods and other natural hazards. These disasters can
be both deadly and costly to society: the
Thistle landslide was the most costly single landslide event in
U.S. history with costs exceeding $400 million. Land began shifting
in Thistle, Utah in 1983 because of groundwater buildup from heavy
rains during the previous fall and the melting of deep snowpack
from the winter. Within a few weeks, the landslide dammed the Spanish
Fork River, destroying U.S. Highway 6 and the main line of the Denver
and Rio Grande Western Railroad. The landslide dam caused flood
waters to rise which in turn led to lead the inundation of the surrounding
area. The town of Thistle was completely obliterated.
occur in all 50 states and claim 25 - 50 lives a year. The U.S.
National Research Council (Committee on Ground Failure Hazards,
1985) estimated that landslides cause between $1.6 billion and $3.2
billion in damage (rates adjusted for inflation) in the U.S. each
subsidence also poses problems for society. Parts of the city and
port of Long Beach, California, suffered major problems due to rapid
(up to 0.75 m yr-1) land subsidence related to extraction of oil
from the underlying Wilmington oil field. Problems were caused by
both inundation due to vertical motion and by horizontal strains
on the sides of the subsidence bowl.
subsidence in Long Beach reached as much as 9 m before the land
surface was stabilized by an integrated program of fluid injection
to balance the extraction. The amount of subsidence at Long Beach
was close to linearly proportional to the amount of petroleum extracted.
Subsidence over petroleum extraction zones can also cause significant
damage to extraction infrastructure itself, including expensive
Lost Hills oil field in central California suffers rapid ground
subsidence due to compaction of the oil reservoir. Click
here for MPEG video of the Lost Hills oil field (5 MB). Monitoring
the subsidence is essential for understanding the deformation of
the reservoir rocks and for optimizing the operation of the oil
field to mitigate the compaction. The rapid and time-varying subsidence
at Lost Hills provides a strong signal for testing and measuring
the error characteristics of several types of elevation change technologies,
which can then be used for other applications.
interaction between climate and tectonics can also affect society.
The Great Flood of 1993 impacted 9 states, causing 48 deaths, and
damaging or destroying at least 50,000 homes. Over 15 million acres
of farmland were inundated and 54,000 people were evacuated from
their homes. The total damage and costs from the Great Floods of
1993 exceeded $21 billion.
to the National Weather Service, the Great Flood actually began
in 1992 when rain and snow saturated the soil. The wet winter was
followed by excessive rain in the spring and summer, causing, from
June to August of 1993, one of the largest floods in history. The
flooding of dozens of rivers, including the Mississippi and Missouri
rivers and eventually lead to the inundation of 9 states. Because
of the saturated soil, the flood waters did not properly drain for
nearly 200 days.
Great Flood of 1993 was the mostly costly flood in the history of
the United States. Annually, floods cause an average loss of $3.5
billion and 140 fatalities in the United States.
Most deaths are related to flash floods- an especially high percentage
of the fatalities occur when people try to drive through waters
over 1 foot deep. If flood-prone areas can be adequately targeted,
then educational outreach and evacuation plans can be implemented
before flash floods strike. Flash floods occur within a few minutes
or hours of excessive rainfall or sudden release of water. Flash
floods, sometimes with heights over 30 feet, can tear out trees,
carry boulders, destroy buildings and bridges, and rip through landscapes,
forming new channels.
term climate studies, more accurate elevation and flood maps, more
frequent monitoring of river water levels, vegetation cover, land
use patterns, water routes, fire history, and topography can all
lead to better understanding of floods, more accurate flood forecasting
losses of such natural hazards include: repair, rebuilding or replacement
public and private property.
to the USGS, indirect costs include:
real estate values and property tax revenues in areas threatened
or affected by landslides
of industrial and agricultural productivity, income and tourism
revenue caused by damage to land or transportation systems
of human and domestic animal productivity due to death, injury
or psychological trauma
of a process-based understanding of the tectonic– climatic–biotic
interactions that create landscapes
Quantification of natural baselines and rates of change of the
of the causes, magnitude, and development in time and space of
Assessment of the relative roles of natural and human-induced
Practical Benefit to Society:
prediction of the progression of floods, landslides, and coastal
of susceptibility to damage by natural hazards
of watershed dynamics, hydrology, and landscape response
of the human role in influencing the landscape and abating and
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