12.3.2 Web Service–Based Near-Real-Time US Vegetation
Condition Monitoring System
The vegetation condition monitoring system (VegScape), funded by NASA and
National Agriculture Statistics Service (NASS) in US Department of Agriculture
(USDA) (58-3AEU-0-0067, PI: Prof. Liping Di), is a Web service-based, near-realtime US vegetation and soil moisture monitoring system (Yang et al. 2013, 2016). It
aims to provide a Web-based service system for research scientists and decisionmakers to monitor and analyze the US vegetation conditions.
Vegetation condition information is significantly important to the agricultural
policy, food production, food security, and food price for US public and government
agencies. To accommodate the growing demands for the vegetation and crop
condition information, VegScape presents on-demand near-real-time monitoring,
automatically online data fetching and analysis, and various vegetation condition
index generations. With the VegScape system, the US users can query, visualize,
disseminate, and monitor the temporal and spatial vegetation condition data through
the standard geospatial Web service over the Web.
The VegScape system monitoring area covers 48 US states (from the year 2000 to
current); it provides diverse vegetation indices, such as normalized difference
vegetation index (NDVI), vegetation condition index (VCI), NDVI ratio to the
previous year (RNDVI), the NDVI ratio to the median (RMNDVI), and mean
referenced vegetation condition index (MVCI) for the vegetation and crop condition
monitoring. All these data products are 250 m for spatial resolution. The NDVI has
daily, weekly, and biweekly data products; the other products all calculated from
NDVI have weekly and biweekly data products. In a Mississippi Delta area case
study, the proposed MVCI shows the best vegetation condition with respect to
10 years of historical average, while the RMVCI shows overall relatively poor
vegetation condition with respect to the historical median (Yang et al. 2011). The
VegScape data component leverages the geospatial interoperability standards and
the near-real-time NASA MODIS data (250 m for spatial resolution and daily for
temporal resolution). Figure 12.2 shows the major data processing flow of
VegScape. Compared to the NASS previous data source from the AVHRR sensor,
the utilization of the MODIS data provides better spatial and temporal resolutions.
Further, it supports better visualization, dissemination, analytics, and assessment of
the vegetation condition. The data component also published the Soil Moisture
Active Passive (SMAP) data (9 km for spatial resolution and daily for temporal
resolution) and intended to access more kinds of data, such as leaf area index (LAI),
fraction of photosynthetically active radiation (fPAR), land surface temperature
(LST), and tropical rainfall measuring mission (TRMM).
Based on the SOA pattern, a Web-based portal is developed to integrate vegetation condition data through interoperable services into decision support information
(e.g., views, maps, reports, tables, charts) (VegScape 2017). The portal has various
online capabilities and includes online navigation, zooming, panning, data
downloading, on-the-fly processing, online statistics, and data profiling. The portal
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L. Hu and P. Yue
Condition Monitoring System
The vegetation condition monitoring system (VegScape), funded by NASA and
National Agriculture Statistics Service (NASS) in US Department of Agriculture
(USDA) (58-3AEU-0-0067, PI: Prof. Liping Di), is a Web service-based, near-realtime US vegetation and soil moisture monitoring system (Yang et al. 2013, 2016). It
aims to provide a Web-based service system for research scientists and decisionmakers to monitor and analyze the US vegetation conditions.
Vegetation condition information is significantly important to the agricultural
policy, food production, food security, and food price for US public and government
agencies. To accommodate the growing demands for the vegetation and crop
condition information, VegScape presents on-demand near-real-time monitoring,
automatically online data fetching and analysis, and various vegetation condition
index generations. With the VegScape system, the US users can query, visualize,
disseminate, and monitor the temporal and spatial vegetation condition data through
the standard geospatial Web service over the Web.
The VegScape system monitoring area covers 48 US states (from the year 2000 to
current); it provides diverse vegetation indices, such as normalized difference
vegetation index (NDVI), vegetation condition index (VCI), NDVI ratio to the
previous year (RNDVI), the NDVI ratio to the median (RMNDVI), and mean
referenced vegetation condition index (MVCI) for the vegetation and crop condition
monitoring. All these data products are 250 m for spatial resolution. The NDVI has
daily, weekly, and biweekly data products; the other products all calculated from
NDVI have weekly and biweekly data products. In a Mississippi Delta area case
study, the proposed MVCI shows the best vegetation condition with respect to
10 years of historical average, while the RMVCI shows overall relatively poor
vegetation condition with respect to the historical median (Yang et al. 2011). The
VegScape data component leverages the geospatial interoperability standards and
the near-real-time NASA MODIS data (250 m for spatial resolution and daily for
temporal resolution). Figure 12.2 shows the major data processing flow of
VegScape. Compared to the NASS previous data source from the AVHRR sensor,
the utilization of the MODIS data provides better spatial and temporal resolutions.
Further, it supports better visualization, dissemination, analytics, and assessment of
the vegetation condition. The data component also published the Soil Moisture
Active Passive (SMAP) data (9 km for spatial resolution and daily for temporal
resolution) and intended to access more kinds of data, such as leaf area index (LAI),
fraction of photosynthetically active radiation (fPAR), land surface temperature
(LST), and tropical rainfall measuring mission (TRMM).
Based on the SOA pattern, a Web-based portal is developed to integrate vegetation condition data through interoperable services into decision support information
(e.g., views, maps, reports, tables, charts) (VegScape 2017). The portal has various
online capabilities and includes online navigation, zooming, panning, data
downloading, on-the-fly processing, online statistics, and data profiling. The portal
226
L. Hu and P. Yue