Dr. Sergio Vicente-Serrano, a globally leading scholar in the area of drought, and his research team members adopt the Standardized Precipitation-Evapotranspiration Index (SEDI), developed by Dr. Daeha Kim and Dr. Jinyoung Rhee from the APEC Climate Center, for global drought monitoring and are using it.

APCC’s SEDI is the number reflecting the water-deficit level during the particular period in the particular region. It is contributing to elevating the reliability of drought prediction information and to monitoring the drought.

Dr. Daeha Kim and Dr. Jinyoung Rhee from the APEC Climate Center conducted the research to reveal the relationship between evapotranspiration and drought, and published their research accomplishment on Geophysical Research Letters. Without using precipitation data, they estimated the amount of evapotranspiration only with the data on temperature and wind velocity during their research.

During this research, they found that they identified the interaction in the water movement between surface and atmosphere with the only information on temperature and wind velocity. This interaction allows the exchange of materials, energy and momentum etc. between surface and atmosphere when the states of water such as vapor, liquid and ice changes.

With only meteorological data, they also identified the regions which showed the strong interaction in water movement between surface and atmosphere. They also discovered the precipitation could be affected, if the amount of evapotranspiration on the surface were varied by the large scale of human activity. they only used the information on temperature and wind velocity instead of the difficult numerical model to come to this conclusion.

And therefore, SEDI is very effective to know the severity and duration of drought in the region which has the strong interaction between atmosphere and surface

Because the severity of drought is estimated based on wet level instead of drying level, the general drought monitoring based on the precipitation shows low reliability in some drought forecasts.

For your reference, A drought monitoring techniques developed by both Dr. Sergio Vicente-Serrano, a leading scholar in the area of drought, and his research team is adopted and used by Drought Portal(https://www.drought.gov/drought/), a US official drought monitoring system. It is globally recognized for its reliabilities.

* A paper related to the SEDI

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2016GL070302

* Dr. Sergio Vicente-Serranos’s paper related to SEDI :

https://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-17-0775.1