Aggregate Dryness Index (ADI)
Index name: Aggregate Dryness Index (ADI).
Ease of use: Red.
Origins: The result of work done at California State University, United States by Keyantash and at the University of California-Berkeley, United States by Dracup in 2003.
Characteristics: A multivariate regional drought index that looks at all water resources across many timescales and impacts. It was developed to be used across uniform climate regimes.
Input parameters: Precipitation, evapotranspiration, streamflow, reservoir storage, soil moisture content and snow water content. The inputs are only used if the region for which ADI is being calculated contains the variable.
Applications: Can be used in the context of multiple types of droughtimpacts. Looking at the total amount of water in a climate regime allows a better understanding of water availability to be made.
Strengths: Takes into account water stored as well as moisture that comes from precipitation.
Weaknesses: Does not take into account temperatures or groundwater, which are accounted for in the description of the ADI.
Resources: The methodology and mathematics are explained in the literature, with examples provided. No code is available for this index.
References: Keyantash, J.A. and J.A. Dracup, 2004: An aggregate drought index: assessing drought severity based on fluctuations in the hydrologic cycle and surface water storage. Water Resources Research, 40: W09304. DOI: 10.1029/2003WR002610.
Greetings to you. I am interested in drought in my country, Iraq. I want to apply this program in my research on drought. How can I get it and how it works? Thank you.
Dear Nasser Wali
Thank you for your question. You can find more information on the ADI and its mathematical formulation in the publication cited on the page above (also here: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2003WR002610).