The Drought-Watch Indices module can calculate five EO-derived drought indices (VCI, TCI, VHI, NDWI, NDDI, and VSWI) and two meteorological indices (SPI and AI) in four temporal scales (day, pentad, dekad and month) by the composition parameters. Both single index and combination index are applied for the drought classification in drought module and the results are demonstrated and saved in different forms.
To improve the drought monitoring abilities in the Belt and Road (B&R), activities were implemented with close cooperation of the B&R countries which included the prioritization of drought indices, field observation, model calibration and validation, customization of SDIM developed Drought Monitoring System (Drought-Watch) and capacity building for drought monitoring technology and system.
Drought-Watch System applies several Earth observation drought indices (EO-derived drought indices) as well as meteorological drought indices (e.g., PED index and Standard Precipitation Index-SPI) for the drought monitoring in different temporal scales (day, pentad, dekad and month) in the Belt and Road. Drought severity is categorized into 5 levels indicating normal, abnormal dry, moderate drought, severe drought and extreme drought.
Using the five types of Drought-Watch drought products (NDDI, VSWI, TCI, VCI and VHI), drought condition in the Belt and Road could be well assessed. For example, Drought-Watch EO-derived drought indices demonstrates that a severe drought occurred in the India during May to June in 2013, also the similar results can be detected by using the PED index, SPI, soil moisture, summer condition, biomass normalization and biomass anomaly.
Availability, simplicity, free of charge data, good research literature and citation, minimum requirements of inputs are main criteria. Sustainability due to the automatization of the analysis. Some improvements should be considered in the future for perfecting drought monitoring model.
Nana Yan, Bingfang Wu, Vijendra K. Boken, Sheng Chang, and Yang Leidong (2016). A drought monitoring operational system for China using satellite data: design and evaluation, Geomatics, Natural Hazards and Risk, 7,264-277
Bin Li, Fang Chen, Feng Xu, and Wang Xinrui (2016). Changes of the time-varying percentiles of daily extreme temperature in China, Theoretical and Applied Climatology, DOI:10.1007/s00704-016-1938-z