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Among the related work we should mention the
SAFORAH project, the work by Daniel Mandl at
NASA, Sentinel/Digital Asia, GEO Grid, and RGI-
project projects, and the tools developed by NASA to
process and deliver data from MODIS/Aster sensors:
the MODIS Rapid Response system and Fire Informa-
tion for Resource Management System.
2 OGC STANDARDS
The WCS standard specifies 3 operations: GetCapa-
bilities, DescribeCoverage, and GetCoverage. These
operations allow spatial, temporal and band subset-
ting, scaling, reprojection, and format encoding.
The WCS-Transactional (WCS-T) extension to
WCS 2.0 allows the insertion and updating of cov-
erages stored on a WCS server. WCS-T specifies an
additional Transaction operation.
The Web Coverage Processing Service (WCPS)
extension to WCS 2.0 defines a flexible interface for
the navigation, extraction, and ad-hoc analysis of
large, multi-dimensional raster coverages. WCPS is
abstract in that it does not anticipate any particular
protocol, and specifies an additional ProcessCover-
ages operation.
Figure 1: MODIS tiling scheme.
3 MODIS SENSOR
MODIS sensor is placed aboard of Terra and Aqua
satellites, both covering the entire surface of the
planet Earth. The planet is divided into 36X8
tiles, and the Portuguese continental land and islands
spread over 3 tiles: h16v05, h17v04 and h17v05.
The spatial resolution of MODIS data can be 250m,
500m or 1000m and classified in 3 categories: atmo-
spheric, land cover, and oceanographic data. NASA
provides this information at several levels, L0 up to
L4, where L0 is raw data and L4 are the most pro-
cessed products. MODIS L2 to L4 products are de-
fined on a global sinusoidal grid. The grid is divided
into fixed-area tiles of approximately 10x10 degrees
in size. Each tile is assigned a horizontal (h) and ver-
tical (v) coordinate ranging from 0 to 35 and 0 to 17,
respectively (figure 1) (Boschetti et al., 2009).
Produced from daily surface reflectance,
MCD45A1 is a monthly L3 500m product that
approximates the date of burning, and maps the
spatial extent of recent fires. MCD12Q1 L3 product
describes land cover properties derived from one
year of observations. It is delivered yearly at 500m
resolution and incorporates 5 different land cover
classification schemes: IGBP, UMD, LAI/FPAR,
NPP, and PFT. Using MODIS reflectances, vegetation
indices are computed daily. Difference Vegetation
Index (NDVI) and Enhanced Vegetation Index (EVI)
are among these indices. MOD13Q1 is a L3 grid
product delivered every 16 days at 500m spatial
resolution. In the present work, we are interested in
the level-3 (L3) land products described in table 1
and selected the IGBP scheme since it is the most
detailed and comprehends 17 classes of land cover
type.
Table 1: MODIS land products.
Product Product Resol. Temporal
Info. Code (m) Granularity
Burned Area MCD45A1 500 Monthly
Veg. Indices MOD13Q1 250 16 Day
Land Cover MCD12Q1 500 Yearly
4 ARCHITECTURE
The architecture that integrates the data provided
by MODIS on the fire spread simulator is sup-
ported by the following technologies: the Hierar-
chical Data Format (HDF) used by NASA to pub-
lish MODIS data, the Java HDF Object Package
that provides an object-oriented interface to HDF
data objects (The_HDF_Group, 2010), and ras-
daman ((rasdaman GmbH), 2011), which is a domain-
independent database management system (DBMS)
with a WCS suite of services built on top of it. From
bottom to top, the architecture (figure 2) includes:
• The postgreSQL relational DBMS that manages
and stores the coverages and their metadata in two
separated databases;
• The core modules of rasdaman that mediate the
interaction between the WCS services (petascope)
and the DBMS, and the format converters;
• petascope implements a OGC-compliant WCS
2.0 suite of services: WCS, WCPS, and WCS-T;
AWCS-BASEDAPPROACHTOINTEGRATESATELLITEIMAGERYDATAINWILDFIRESIMULATION
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