28,578 research outputs found
OPEN SOURCE SOFTWARE AND OPEN EDUCATIONAL MATERIAL ON LAND COVER MAPS INTERCOMPARISON AND VALIDATION
Land Cover (LC) maps represent key resources to understand, model and address many global and local dynamics affecting our planet. They are usually derived from the classification of satellite imagery, after which a validation or intercomparison process is performed to assess their accuracy. This paper presents the project “Capacity Building for High-Resolution Land Cover Intercomparison and Validation”, an educational initiative funded by the International Society for Photogrammetry and Remote Sensing (ISPRS) and mainly targeting developing countries. First, with the help of two open surveys, an analysis of the state of the art was performed which assessed the overall good awareness on LC maps and the needs and requirements for validating and comparing them, as well as the rich availability of educational material on this topic. The second task, currently under finalization, is the development of new educational material, based on open source software and released under an open access license, consisting of: an introduction to the GlobeLand30 (GL30) LC map and its online platform; a desktop GIS procedure showing two use cases on GL30 validation; and an application to collect LC data on the field to be used for validation. Finally, this educational material will be tested in practice in three workshops during the second half of the project, two of which held in developing countries: Dar es Salaam, Tanzania and Nairobi, Kenya
An open and extensible framework for spatially explicit land use change modelling in R: the lulccR package (0.1.0)
Land use change has important consequences for biodiversity and the
sustainability of ecosystem services, as well as for global
environmental change. Spatially explicit land use change models
improve our understanding of the processes driving change and make
predictions about the quantity and location of future and past
change. Here we present the lulccR package, an object-oriented
framework for land use change modelling written in the R programming
language. The contribution of the work is to resolve the following
limitations associated with the current land use change modelling
paradigm: (1) the source code for model implementations is
frequently unavailable, severely compromising the reproducibility of
scientific results and making it impossible for members of the
community to improve or adapt models for their own purposes; (2)
ensemble experiments to capture model structural uncertainty are
difficult because of fundamental differences between implementations
of different models; (3) different aspects of the modelling
procedure must be performed in different environments because
existing applications usually only perform the spatial allocation of
change. The package includes a stochastic ordered allocation
procedure as well as an implementation of the widely used CLUE-S
algorithm. We demonstrate its functionality by simulating land use
change at the Plum Island Ecosystems site, using a dataset included
with the package. It is envisaged that lulccR will enable future
model development and comparison within an open environment
Senior Thesis ST 2011-02
Agriculture in the Arctic is often limited by the low receipt
of heat energy, which is often measured in growing degree
days (GDD). With the advent of increasingly powerful climate
modeling, projection and downscaling techniques, it is becoming possible to examine future climates in high resolution.
Recent availability in Alaska has prompted interest in examining the distribution of current and the potential future of
local agriculture. The goal of this study was to utilize Scenarios
Network for Alaska Planning (SNAP) downscaled, ensemble
projections to examine this in terms of GDDs in the Fairbanks
North Star Borough of Alaska. Historic and projected monthly
mean temperatures were utilized to calculate GDDs and then
map the borough at a 4 km2 scale. Additionally, local agriculturalists were interviewed in order to put these theoretical calculations into context. Ultimately, projections of the examined agricultural locations showed an average of a 2% increase
in GDD per decade and a 26% increase in GDDs from 1949
to 2099. This project indicated that the North Star Borough
will receive increased heat energy due to climate change over
the next century that may further enable increased yields and
varieties of crops
Seafloor characterization using airborne hyperspectral co-registration procedures independent from attitude and positioning sensors
The advance of remote-sensing technology and data-storage capabilities has progressed in the last decade to commercial multi-sensor data collection. There is a constant need to characterize, quantify and monitor the coastal areas for habitat research and coastal management. In this paper, we present work on seafloor characterization that uses hyperspectral imagery (HSI). The HSI data allows the operator to extend seafloor characterization from multibeam backscatter towards land and thus creates a seamless ocean-to-land characterization of the littoral zone
GMES-service for assessing and monitoring subsidence hazards in coastal lowland areas around Europe. SubCoast D3.5.1
This document is version two of the user requirements for SubCoast work package 3.5, it is
SubCoast deliverable 3.5.1. Work package 3.5 aims to provide a European integrated GIS
product on subsidence and relative sea level rise. The first step of this process was to
contact the European Environment Agency as the main user to discover their user
requirements.
This document presents these requirments, the outline methodology that will be used to carry
out the integration and the datasets that will be used. In outline the main user requirements
of the EEA are:
1. Gridded approach using an Inspire compliant grid
2. The grid would hold data on:
a. Likely rate of subsidence
b. RSLR
c. Impact (Vulnerability)
d. Certainty (confidence map)
e. Contribution of ground motion to RSLR
f. A measure of certainty in the data provided
g. Metadata
3. Spatial Coverage - Ideally entire coastline of all 37 member states
a. Spatial resolution - 1km
4. Provide a measure of the degree of contribution of ground motion to RSLR
The European integration will be based around a GIS methodology. Datasets will be
integrated and interpreted to provide information on data vlues above. The main value being
a likelyhood of Subsidence. This product will initially be developed at it’s lowest level of detail
for the London area. BGS have a wealth of data for london this will enable this less detialed
product to be validated and also enable the generation of a more detailed product usig the
best data availible. One the methodology has been developed it will be pushed out to other
areas of the ewuropean coastline.
The initial input data that have been reviewed for their suitability for the European integration
are listed below. Thesea re the datasets that have European wide availibility, It is expected
that more detailed datasets will be used in areas where they are avaiilble.
1. Terrafirma Data
2. One Geology
3. One Geology Europe
4. Population Density (Geoland2)
5. The Urban Atlas (Geoland2)
6. Elevation Data
a. SRTM
b. GDEM
c. GTOPO 30
d. NextMap Europe
7. MyOceans Sea Level Data
8. Storm Surge Locations
9. European Environment Agencya.
Elevation breakdown 1km
b. Corine Land Cover 2000 (CLC2000) coastline
c. Sediment Discharges
d. Shoreline
e. Maritime Boundaries
f. Hydrodynamics and Sea Level Rise
g. Geomorphology, Geology, Erosion Trends and Coastal Defence Works
h. Corine land cover 1990
i. Five metre elevation contour line
10. FutureCoas
Analyzing the discharge regime of a large tropical river through remote sensing, ground-based climatic data, and modeling
This study demonstrates the potential for applying passive microwave satellite sensor data to infer the discharge dynamics of large river systems using the main stem Amazon as a test case. The methodology combines (1) interpolated ground-based meteorological station data, (2) horizontally and vertically polarized temperature differences (HVPTD) from the 37-GHz scanning multichannel microwave radiometer (SMMR) aboard the Nimbus 7 satellite, and (3) a calibrated water balance/water transport model (WBM/WTM). Monthly HVPTD values at 0.25° (latitude by longitude) resolution were resampled spatially and temporally to produce an enhanced HVPTD time series at 0.5° resolution for the period May 1979 through February 1985. Enhanced HVPTD values were regressed against monthly discharge derived from the WBM/WTM for each of 40 grid cells along the main stem over a calibration period from May 1979 to February 1983 to provide a spatially contiguous estimate of time-varying discharge. HVPTD-estimated flows generated for a validation period from March 1983 to February 1985 were found to be in good agreement with both observed arid modeled discharges over a 1400-km section of the main stem Amazon. This span of river is bounded downstream by a region of tidal influence and upstream by low sensor response associated with dense forest canopy. Both the WBM/WTM and HVPTD-derived flow rates reflect the significant impact of the 1982–1983 El Niño-;Southern Oscillation (ENSO) event on water balances within the drainage basin
Land Use Changes and Their Perception in the Hinterland of Barranquilla, Colombian Caribbean
The coastal strip of the western peri-urban area of Barranquilla in the Atlántico Department (Colombia) is experiencing changes in human-environment interactions through infrastructure, residential, and tourism projects in a vulnerable landscape. In the hilly area, fragments of biodiverse tropical dry forest still exist in various states of conservation and degradation. To understand the interrelated social, economic, and ecological transformations in the area, we analyzed land use change on the local scale including the local community’s perception, because the local community is a key actor for sustainable land use. For the analysis of the interrelated social, economic, and ecological processes, we combined visual interpretation of high-resolution satellite imagery, on-site field land use mapping, and a spatial statistical analysis of the distribution of land use classes with in-depth interviews and a participatory GIS workshop, thus benefitting from the complementary methodological strengths of these approaches. The case study is the rural community of El Morro, which exhibits the typical social, economic, and ecological changes of the coastal strip of the western peri-urban area of Barranquilla. The local community perceives a continuous loss of forest area, but observations from on-site field mapping cannot confirm this linear trend. We observed a gradual replacement of traditional land uses such as smallholder agriculture, charcoal production, and cattle breeding by services for tourism, gated community projects for urban dwellers, and infrastructure projects; these spatial developments have several characteristics of rural gentrification. We conclude that the drivers of environmental degradation have changed and the degradation increased. The development projects of external companies have been rejected by the local community and have induced environmental consciousness among community members. Thus, the local community has become an advocate for sustainable land use in the study area
Compilation and validation of SAR and optical data products for a complete and global map of inland/ocean water tailored to the climate modeling community
Accurate maps of surface water extent are of paramount importance for water management, satellite data processing and climate modeling. Several maps of water bodies based on remote sensing data have been released during the last decade. Nonetheless, none has a truly (90°N/90°S) global coverage while being thoroughly validated. This paper describes a global, spatially-complete (void-free) and accurate mask of inland/ocean water for the 2000–2012 period, built in the framework of the European Space Agency (ESA) Climate Change Initiative (CCI). This map results from the synergistic combination of multiple individual SAR and optical water body and auxiliary datasets. A key aspect of this work is the original and rigorous stratified random sampling designed for the quality assessment of binary classifications where one class is marginally distributed. Input and consolidated products were assessed qualitatively and quantitatively against a reference validation database of 2110 samples spread throughout the globe. Using all samples, overall accuracy was always very high among all products, between 98% and 100%. The CCI global map of open water bodies provided the best water class representation (F-score of 89%) compared to its constitutive inputs. When focusing on the challenging areas for water bodies’ mapping, such as shorelines, lakes and river banks, all products yielded substantially lower accuracy figures with overall accuracies ranging between 74% and 89%. The inland water area of the CCI global map of open water bodies was estimated to be 3.17 million km2 ± 0.24 million km2. The dataset is freely available through the ESA CCI Land Cover viewer
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