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The LRS Program conducts and sponsors
research in remotely sensed land data collection, access,
distribution, and applications. Scientists and engineers
sponsored by the Program are investigating new types of
satellite systems and sensors, studying promising new data
sources, developing new data acquisition programs and sources,
and assessing the potential for new data applications. The
Program is seeking new ways to make remotely sensed data
products more accessible and to expand and enhance the overall
use of remotely sensed data and remote sensing technology.
Project Summaries are organized by the following science topics:
Hazards, Sensors
and Data, Natural Resources,
Earth Observations and Monitoring.
Hazards
- Hurricane Information, Community Vulnerability
and Public Policy in the Gulf Coast:
- Develop and apply methods for examining the value, format,
and transfer of knowledge for societal decision making
and policy analysis. Recent scientific evidence suggests
we may be entering a period of increased hurricane frequency
and intensity, making the need for reliable, useful, and
understandable scientific information on community vulnerability
to hurricanes even more critical than in the past. The
maps, videos, photographs and digital elevation products
produced by the USGS in near- real time during hurricanes
and distributed via the Internet are widely used by the
media, officials from federal, state and local agencies,
and the general public. However, very little is understood
about the characteristics of the user communities for
these products, how effective the products are for hurricane
response, recovery and mitigation, or how these products
might be improved.
- Landslide Delineation and Slope Morphology Characterization:
- Slope stability is typically the product of the equilibration
of site specific conditions. A slope can become unstable
when those conditions are disturbed by human activities,
precipitation, or seismic events. An understanding the
physical processes that contribute to slope stability
provides insight into those processes that can result
in slope instability or failure. Clearly defining the
physical characteristics of a slope, and the processes
or conditions that may result in that slope becoming unstable
or failing is at the forefront of current landslide research.
One approach to addressing these issues is to refine methods
of identifying existing landslides, and describing slope
morphology.
- Landslide and Debris Flow:
- The USGS has signed an agreement with the National Weather
Service and the U.S. National Oceanic and Atmospheric
Administration Office of Oceanic and Atmospheric Research
to develop a debris-flow hazards alert/warning system
protocol with input from emergency managers and responders.
The USGS responsibility under this agreement is to develop
better rainfall threshold models in southern California
and elsewhere to aid in issuing public warnings. The pilot
study area is in the San Bernardino Mountains within the
Los Angeles metropolitan area of southern California.
With other partners, USGS is developing a decision support
system to assist end users in assessment of debris-flow
hazards in recently burned basins.
- Tectonic Applications: Early Warning and Environmental
Monitoring:
- This project will investigate coupling of the recent M9 2004
and M8.7 2005 earthquakes in the Sumatra-Andaman Subduction
Zone (SASZ), how these events change the likelihood for other
earthquakes in the region, and the use of remote sensing data
to constrain the surface deformation estimates generated by
finite element models (FEMs). Better information on surface
deformation fields will provide improved estimates of earthquake
rupture at depth. Improved estimates of rupture will eventually
allow increased accuracy in earthquake prediction. A simple
static Coulomb stress analysis confirms the M9 event dramatically
increased the tendency for rupture to occur along the fault of the
subsequent M8.7 event. However, static Coulomb stress cannot
account for the three-month delay of the M8.7 event. The delay can be
accounted for if we understand the evolution of Coulomb stress following
the M9 event, which in turn, requires that we understand the post-seismic
deformation mechanisms at work following the M9 event. The incorporation
of quantitative and qualitative information on post-seismic deformation
(derived from remote sensing datasets) will, thus, play an important role.
- Urban Hazards:
- Land surface imperviousness is an excellent indicator of
environmental quality, especially in regard to the health
of hydrologic features on the land surface. Water quality
of rivers, lakes, estuaries and wetlands has been found to
decrease with increases in the percent of impervious land
cover. Increased imperviousness also causes larger quantities
of stormwater runoff that contribute to localized flooding.
The detection and mapping of impervious surfaces using current
remote sensing systems is problematic for different geographic
regions of the United States because of unique environmental
characteristics. This project is investigating the utility
of remotely sensed data sets acquired from current satellite
and airborne systems for discriminating and mapping imperviousness
in different geographic environs of the country.
- InSar and Great Earthquakes:
- Crustal deformation, including folding or tilting of rocks
at the Earth’s surface as well as areas of uplift
and subsidence expressed as topographic anomalies, pre-date
great earthquakes (Castle and others, 1974; Li and Rice,
1983; Berberian and Qorashi, 1994; Castle and Bernknopf,
1996). Geodetic data from tilt, creep and strain meters
are used to monitor crustal deformation as a precursor
to earthquakes. These data, however, are difficult to
collect, reduce, and interpret (Malcolm Johnson, USGS
written comm., 1999) and of little value if the geodetic
station is more than 50 km from the epicenter of an earthquake.
These problems may be resolved by using interferometric
synthetic aperture radar (InSAR) images. InSAR has been
used to measure repeatedly very small changes (2-3 mm)
in elevation over areas as large as 10,000 km2 of the
Earth’s surface (Lu and others, 2000; Massonnet
and Feigl, 1998; Lunetta and Elvidge, 1998). These elevation
changes have been associated with volcanic activity, ground
water subsidence, or deformation associated with active
faults (Lu and others, 1998, 2000; Burgmann and others,
1998). To date, InSAR research on active faults has focused
on post-seismic deformation (Massonnet and others, 1996;
Peltzer and others, 1998; Pollitz and others, 2001). This
research will focus on surface deformation prior to great
earthquakes.
- Satellite and Airborne Imaging and Analyses:
Map and Monitor the Wildland/Urban Interface as it Relates
to Wild Fire Hazards:
- With the increased resolution of satellite and airborne
digital imaging remote sensing is a promising tool that
needs to be investigated fully to document its capabilities
and limitation for applications dealing with wild fires,
including the potential for detecting, mapping, and monitoring
the wildland/urban interface. The project team lives in
Flagstaff, which is one of the communities identified
as ‘at high risk’ to wild fires, and it will
be one of the initial study sites. Therefore, this project
would be an excellent example of Geography Discipline
employees being on the landscape and working closely with
the local federal, state, county, and city land managers
on a critical and high priority issue.
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Sensors and Data
- Evaluate the Vertical Accuracies of Direct Geo-referenced
Lidar Elevation Data:
- Information concerning the vertical accuracy and reliability
achievable of Lidar data is essential to applications research.
The emerging Lidar and GPS/INS technology has the potential
to greatly reduce the cost of projects and improve vertical
accuracy of elevation data. This advanced technical capability,
if successful, will enable the feature extraction of Lidar
elevation data for contours, hydrographic, and structure
information, more accurately and cost-effectively.
- Exploitation and Application of Hyperspectral
data – Powder River Basin:
- The Powder River Basin is undergoing landscape changes related
to the development and extraction of coalbed methane. Many
environmental and land management concerns relate to this
development. The extraction process produces large volumes
of water that must be disposed of or put to beneficial use.
Common water management strategies are to discharge the
water into drainages, stock ponds, or infiltration ponds,
or to apply the water directly to the land surface via irrigation
or atomizers. The suitability of soils for these purposes
varies and it is important to avoid application onto soils
containing swelling clays; therefore, land managers need
data on the soil types, especially the location of these
types of surficial clays, to determine the feasibility of
direct land application of these sodium dominated waters.
An additional concern is that the addition of co-produced
water into the environment seems likely to encourage the
spread of riparian related invasive species, including tamarisk.
- Exploitation and Application of LIDAR - Gunnison
Gorge:
- Waterborne selenium and alkaline salts cause major concern
and expensive mitigation along the Colorado River. The Mancos
Shale unit is known to contribute a majority of the salt,
sediment, and selenium to the Gunnison and Uncompahgre River
basins, which are major tributaries in the upper Colorado
River basin. High resolution elevation and imagery data
are required to address science and land- management issues
being studied by the Mancos Shale Landscapes interdisciplinary
USGS/BLM DOI project. In FY05, high-resolution lidar, orthorectified
digital imagery, and a fused product of these (SILC –
Spectral Imagery Lidar Composite) were acquired for part
of the BLM-administered Gunnison Gorge National Conservation
Area in western Colorado underlain by selenium- and salt-bearing
Mancos Shale. Accurate GPS control was also planned to be
collected over some of the data acquisition areas in late
FY05.
- Applications of Active Remote Sensing Systems:
Topographic Science:
- Recent advances in data from active remote sensing systems,
specifically lidar and SAR systems have set the stage for
progress in producing derived information products that
are difficult to produce from passive optical systems. This
project will conduct research on vegetation and hydrologic
derivatives from active remote sensing systems data, and
initiate a coordination effort for science applications
of lidar data.
- Effects of Data Resolution on Land Cover maps:
- Land surface heterogeneity can affect how well land cover
values are related at different scales. Vegetation type
and condition can change dramatically between the site and
spectral data at the pixel level for most airborne and space-borne
sensors. Direct application of site information to larger
areas is only reasonable over homogeneous stands that are
at least as large as the pixel being used. As one increases
the area observed using remotely sensed information, heterogeneity
increases due to a complex interacting increase in biological
(vegetation types and conditions), physical (topographic
influences), and atmospheric (optical density) influences
on the data recorded by the sensor, therefore making the
classification of land cover at different scales problematic.
- Vegetation Surface Model: Quantification of Urban
Vegetation:
- Current methods of quantifying urban biomass and regional
studies are often at a coarse scale and ineffective for
ecological decision makers attempting to address policy
decisions. Lidar data provides a new opportunity to reduce
field collection and data interpretation for quantifying
vegetation at a scale appropriate for land use managers
to improve the health and resilience of ecoregions.
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Natural Resources
- Land Surface Hydrology:
- A complete understanding of environmental processes requires
knowledge of the impact that spatially and temporally variable
land surface properties have on hydrology and climate. Models
are one tool scientists use to refine understanding of processes
and inform resource management. Theoretically, hydrology
and climate models require the best land cover information
possible. In practice however, what constitutes 'best' or
even 'adequate' land cover information is not known by model
developers or users. This task derives and analyzes land
surface information to measure the importance of land dynamics
in hydrologic and climate processes and improve land cover
information use for specific resource management activities.
- Ozark Plateau Study:
- To date no National Water Quality Assessment Program (NAWQA)
study unit has had a historical land cover chronology completed
for its study area. Nor has any study unit used the remote
sensing technology to look at the relation of biotic reflectance
to the chemical and physical constituents collected within
the NAWQA program or the effectiveness of using remote sensing
as a generalized surrogate water quality monitoring tool.
This project tries to address these issues.
- Modeling Watershed Erosion Vulnerability in Coastal Regions
- New efforts dealing with modeling landscape erosion vulnerability
and methods to do high temporal monitoring of sediment loads
eroded from different portions of a watershed will be of
interest to not only these groups, but also to many others
on the main-land who have similar concerns about the impact
of watershed erosion on the surrounding landscape and total
sediment loads in small and large rivers. New algorithms
and/or procedures to map and monitor erosion vulnerability
of watersheds, as well as the design and development of
a new low-cost field based instrument to monitor total sediment
load at a high temporal resolution, will be applicable to
large rivers and surrounding watersheds/drainages.
- Developing and evaluating new in-the-field protocols
to detect and monitor watershed erosion:
- At the Hanalei watershed the river flows year round with
sediment load increasing during runoff events. Mt. Waialeale,
the uppermost point of the Hanalei watershed, averages over
400 inches of rainfall annually. Much of this watershed
has been impacted by natural events (two major hurricanes
in the past 25 years), and alien factors (feral pigs destroying
the ground-layer vegetation), with the spread of alien plant
species after disturbance by both hurricanes and pigs. Because
of the need to calibrate and validate our spectral radiometer
results with either extensive water sampling and/or using
an existing proven method for sediment monitoring we will
make the Hanalei watershed/river in north Kauai our initial
study site. Most of the work to design and develop the new
low-cost two band spectral radiometer and test it will be
done at the Hanalei watershed site, with follow up testing
at a very different watershed on east Molokai. The Molokai
drainages are dry except when runoff occurs. Reducing erosion
and sedimentation at the Molokai site is extremely important
to NPS, FWS, The Nature Conservancy of Hawaii, and other
private landowners relative to reducing down slope sedimentation,
particularly along the shoreline and in the near-shore marine
environment. With the combination of the Hanalei and east
Molokai sites we will be able to investigate the capabilities
and limitations of our new procedure in very different watershed
environments.
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Earth Observations and Monitoring
- Consequences of Potomac Watershed Land-use and
Land Cover Change:
- The Potomac Watershed has been changed by human-induced
and natural processes, some of which have significant impact
on ecosystem health and sustainability. Improved information
and understanding about the state of the land surface; and
the rates and patterns, causes/drivers, and consequences
of landscape change are needed to help scientists and decision-makers
in land-use planning, land management, and natural resource
utilization/conservation. The need to integrate and apply
information to help understand the consequences of land
surface change on sediment erosion and deposition, forest
quality, habitat fragmentation, overall ecosystem and watershed
health, and other factors operating at local and broad regional
scales is critical to managing the natural resources of
the Potomac Watershed and Chesapeake Bay.
- The Relationships and the Consequences of Land-use
and Land Cover Change in the Chesapeake Bay Watershed:
- Throughout the Chesapeake Bay watershed, post-colonial settlement
transformed the region from predominantly forested in the
17th century to predominantly agricultural in the 19th century.
Land cover changes in the 20th century and at present are
mostly characterized by a transition from agriculture to urban
and forests. Urbanization is the dominant trend within
commuting distance to major job centers. These phenomena and
other landscape changes in the Bay watershed pose both constraints
and opportunities for meeting the water quality and habitat
restoration goals of the Chesapeake Bay Program Partnership.
In response to these phenomena, the Bay Program Partners have
expressed a strong need for understanding the environmental
implications of past, present, and potential future land cover
changes on the health of the Chesapeake Bay and on efforts to
restore it.
- Biodiversity Characterization: Landcover Applications,
Landscape Dynamics, and Global Change:
- Biodiversity in North and Central America is diminishing
at an alarming rate resulting in serious ecosystem and societal
consequences (Chapin, 2000,CEC, 2002). Yet, our understanding
of the characteristics and dynamics of biodiversity is limited.
Neither biodiversity resources nor their associated threats
and consequences are evenly distributed. In response, conservation
organizations have identified priority conservation areas
(PCA) including "biodiversity hot spots", "global-200
ecoregions", and "priority conservation regions".
Although boundaries of these areas are reasonably well demarcated,
we do not know how much of a given habitat remains in and
around those areas, what is the biophysical condition, what
is the extent and scale of habitat fragmentation, what are
the major threats, and what changes are likely to occur
in the future under various global climate change scenarios?
To answer these research questions and support planning
and management in the conservation areas, a regional synthesis
of North and Central America is urgently needed. It is also
necessary to explore the applicability of recently available
MODIS-500m data for land cover characterization and mapping
at regional/continental scale focusing on what can be discerned
and what is needed. Development of new methods and techniques
combining satellite data interpretation techniques, geo-spatial
analyses, and climate modeling are equally important.
- Carbon Cycle Research: Landcover Applications,
Landscape Dynamics, and Global Change:
- Rangelands are expected to be useful carbon sinks given
their large spatial extents and the fact that most of their
carbon is stored below ground. Overgrazing and degraded
rangelands represent opportunities to make rangeland improvements
with benefits for carbon sequestration and the reduction
of erosion. Identification of degraded rangelands is needed
to focus extension efforts and water quality reporting requirements.
As ecosystems respond to climate change, we expect changes
in vegetation communities and ecosystem functionality, particularly
on fringe areas where two or more plants systems are operating
at their climatic or competitive extremes. Alteration of
ecosystem function is dramatic is some cases, such as the
conversion of a deep rooted perennial sagebrush system to
a short rooted annual grass system (for example, Cheatgrass).
In this task, remotely sensed data will be combined with
spatial climatic data sets to monitor how vegetation productivity
(remotely sensed vegetation indices) respond to climate.
Consistent changes in “ecosystem functionality”
over several years will indicate areas of probable changes
in plant communities.
- Biological Applications: Early Warning and Environmental
Monitoring: Website
- Biological Applications (BA) is focused on developing and
extending applications for earth observations in local-,
regional-, and national-scale monitoring of terrestrial
biological processes (in regards to the vegetation canopy).
Within this task, we support a number of applications for
and users of remote sensing phenology. Phenology involves
the study of periodic biological events as influenced by
the environment, especially weather and climate. Global
change studies have a growing need for measures of phenology
over large-areas. Droughts are one type of cyclic climate-driven
phenomena with broad spatial and temporal variability and
far-reaching, often costly consequences.
- SLC - Off Agriculture: Early Warning and Environmental
Monitoring:
- The US Department of Agriculture (USDA) is one of the
largest customers of Landsat imagery. The Scan Line
Corrector (SLC) failure on Landsat 7 has resulted in a
serious data gap for USDA who rely on Landsat data to
continuously monitor crop condition and develop annual
crop maps both nationally and internationally. This research
focuses on development and testing of a gap-fill method that
meets the needs of the agricultural community for date-sensitive
monitoring information.
- Alaska 1980's Land Cover Map:
- Over the past 25 years, Federal Agencies have mapped approximately
three-quarters of Alaska using a variety of imagery including
aerial photography, Landsat (MSS and TM) and SPOT; the remaining
one fourth to one third of the state has no coverage. The
resolution of these data range from 50 to 30-m pixels. The
majority of existing map classifications used have been
cross-walked to either an Interim Land Cover Classification
or an International Geosphere-Biosphere Program (IGBP) scheme;
however, some have not. This proposed project would 1) using
existing circa 1980 satellite imagery to produce complete
statewide land cover data and 2) produce a single map at
one scale using consistent map classes using a variety of
existing and new data sources.
- Assessment of Lake Change in Alaska:
- Recent studies have reported that lakes in Alaska are drying
up; however, these studies have occurred over small sample
areas within Alaska and it is not known how widespread the
problem is, if it is related to any specific region, nor
is it known about the rate of drying or the type of lakes
that are involved.
This study would use a number of different aerial and satellite
imagery to assess the extent, rate, and type of lake drying
occurring across Alaska. Initial, a sampling approach similar
to that of the Status and Trends project will be used to
select sample areas within the various ecoregions of Alaska.
The intent of the sample would be to provide sufficient
information that would report on the amount and distribution
of drying lakes within each ecoregion and across the state.
Initially, there would be two types of lakes mapped, those
that are fed by surface run-off and those that have inlet/outlets;
there may also be a third, ephemeral, if we can identify
them. Once the sample regime was in place, lakes would be
identified using aerial photos (circa 1950s, 1970-80s) and
Landsat (1970's to present) to assess the type of lake,
the location, the amount of drying, and trends. For the
more near time (circa 2000) lake database, MODIS data would
be assess to see if 1) the type and amount of lakes could
be monitored at the courser resolution, and 2) if MODIS
data could be used as a monitoring tool to be used on a
yearly basis. Other types of high resolution satellite imagery
would also be used for assessment of using Landsat data
for assessing lakes smaller than the nominal Landsat pixel
size.
- Analyze Land Use Change in the Tahoe Basin:
- Human activity in the Lake Tahoe Basin has increased substantially
in the past four decades causing significant impacts on
the quality and clarity of the lake's famous deep, clear
water. Protection of Lake Tahoe and the surrounding environment
has become an important activity in recent years. In spite
of past and ongoing efforts to understand how the lake functions
and to what extent humans have affected its landscape and
ecosystem processes, there remains a lack of comprehensive
temporal land use/land cover (LULC) change data and analysis
for the Basin.
- Landscape change, Grassland Health, Bark Beetle
and Tamarisk Infestation on the San Carlos Indian Reservation:
- Using LANDSAT imagery scenes (spatial resolution 30 M Color,
15M Panchromatic and approximately 20M merged Color and
Panchromatic) delineate surface area of water bodies (at
maximum capacity) that includes; lakes, ponds, sediment
traps, earth embankment tanks and stock tanks falling within
the spatial resolution of the Landsat Imagery, which normally
requires 2 – 3 pixels to identify features. Compute
total water surface area, as identified on Landsat imagery,
for the F.A.I.R. Compare water bodies identified with Landsat
imagery with High resolution aerial photography acquired
by the FAIR, determine percentage of water bodies identified
using Landsat imagery and make determination as to use of
high/very high-resolution satellite or aerial photography
to identify and quantify remaining surface water bodies.
Develop techniques to monitor, on a regularly scheduled
basis, status of surface water on FAIR using remotely sensed
data.
- Salton Sea air quality investigation as it relates to dust:
On-land surface characterization using remote sensing:
- As water transfer mitigation measures in the Salton Sea
Basin end, the water surface level of the Salton Sea will
systematically decrease and shoreline sediments will be
exposed to wind-driven erosion and may become an airborne
health hazard. Airborne particulate matter poses a risk
to human health. Little is known about the airborne suspension
potential of sediments in the Salton Sea and there is a
significant concern about the current air quality within
the Salton Sea sink. The concern will increase, at both
local and regional levels, as the potential for air quality
conditions worsen due to future inflows into the Sea decreasing
and exposed sediments increasing. There is a need to establish
current baseline sediment/air quality characteristics of
the Sea (sediment types, re-suspension potential, wind characteristics,
point source localities, etc.) and to determine future potential
conditions as physical conditions of the Sea changes through
time.
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