Global Drought Monitoring Service through the GEOSS Architecture ...

Architectural Implementation Pilot, Phase 3 Version: 2.0
Global Drought Monitoring and European Drought
Observatory-Water SBA Engineering Report
Date: 11/Feb/2011
Figure 1 LISFLOOD forecasted normalized top soil moisture suction (pF) for Europe. The pF
values have been normalized by ECMWF ERA-40 statistics.
2.1.3 EDO-deployed Meteorological Drought Indicator: Standardized
Precipitation Index
Precipitation anomalies are expressed the monthly Standardized Precipitation Index (SPI)
of the last month, a well-known meteorological drought index. Monthly SPI values reflect short
term changes in precipitation as compared to the long-term average of the respective month.
Positive SPI values indicate greater than median precipitation, and negative values indicate less
than median precipitation (McKee et al. 1993).
2.1.4 Hydrologic Drought Indicator
A hydrological drought is described usually by the analysis of stream-flow, lake, or
reservoir level data. Opposite to meteorological information, hydrological data are collected
throughout Europe, but are generally stored locally at the national or even regional level, often
with varying formats and qualities less consistent than for meteorological data. Here, after
careful calibration, the hydrological model LISFLOOD might contribute to the forecasting of
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