Palmer Hydrological Drought Index (PHDI)
Index name: Palmer Hydrological Drought Index (PHDI).
Ease of use: Yellow.
Origins: Part of the suite of indices developed by Palmer in the 1960s with the United States Weather Bureau.
Characteristics: Based on the original PDSI and modified to take into account longer-term dryness that will affect water storage, streamflow and groundwater. PHDI has the ability to calculate when a drought will end based on precipitation needed by using a ratio of moisture received to moisture required to end a drought. There are four drought categories: near normal, which occurs approximately 28%–50% percent of the time; mild to moderate, which occurs approximately 11%–27% percent of the time; severe, which occurs approximately 5%–10% percent of the time; and extreme, which will occur approximately 4% of the time.
Input parameters: Monthly temperature and precipitation. Information on the water-holding capacity of soils can be used, but defaults are also available. A serially complete record of temperature and precipitation data is required.
Applications: Most useful for taking into account drought affecting water resources on longer timescales.
Strengths: Its water balance approach allows the total water system to be considered.
Weaknesses: Frequencies will vary by region and time of year, where extreme drought may not be a rare event during some months of the year. The impact of human influences, such as management decisions and irrigation, are not considered in the calculations.
Resources: The code can be found in the original Palmer paper in the reference below. More explanations can be found in: Jacobi, J., D. Perrone, L. Lyons Duncan and G. Hornberger, 2013: A tool for calculating the Palmer drought indices. Water Resources Research, 49: 6086–6089. DOI: 10.1002/wrcr.20342.
Reference: Palmer, W.C., 1965: Meteorological Drought. Research Paper No. 45. United States Weather Bureau, Washington, DC.
Currently used by: Trinidad and Tobago.
26 Responses
Can i use Monthly precipitation,monthly PET and soil moisture as input variables to calculate PHDI?
I want to calculate PHDI in CPEC-Region and i have got the monthly precipitation and temperature data from 1981 to 2023. Can you provide me the default values of soil water holding capacity for my area or suggest me any reliable platform according to my area of interest. Thanks
I am a PhD student and want to calculate PHDI. Can you tell me which input data are required for this and suggest me any tool to calculate PHDI. Please also share the link of that tool if any have.
Dear Akash Hussain,
Thanks a lot for reaching out! As indicated above these are the input parameters needed: Monthly temperature and precipitation. Information on the water-holding capacity of soils can be used, but defaults are also available.
As for a tool: there are several R packages and other tools around to calculate PHDI. One specific tool would be: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/wrcr.20342
Kind regards,
Your IDMP TSU
Can someone please tell me if PDSI and PHDI have the same formula? If yes share, please. Thanks
The Palmer Drought Severity Index (PDSI) and the Palmer Hydrological Drought Index (PHDI) are related indices used to measure drought, but they have different methodologies and applications, so they do not use the same formula. PDSI is more suitable for short-term drought monitoring, while PHDI is better for assessing longer-term hydrological impacts. PDSI focuses on meteorological and agricultural drought and accounts for precipitation, temperature, and available soil moisture to quantify drought or wetness. It uses a complex water balance model to calculate the index.
PHDI focuses on long-term hydrological drought conditions. It uses the same input data (precipitation, temperature) but is adjusted to reflect long-term hydrological impacts like groundwater storage, reservoir levels, and river flows.
You will find the respective formulas in the handbook.
Kind regards,
Your IDMP TSU
can someone tell me if PDSI and PHDI have the formula
Hello,
in Palmer’s paper, exactly which symbol can be seen as the PHDI?
Dear Simon
According to the paper (e.g. pp 21, 27, 28), an X is used for the drought index.
Best regards
IDMP TSU
typo in my email: it is bamforth@colorado.edu
I know there are drought reconstructions for North America using PDSI that rely on data from tree- ring sequences and go back about 2000 years. Do you know if it is possible to use tree-ring data to compute the PHDI? If so, has anyone done it? The 2013 Jacobi et al paper seems to say that computing PHDI depends on much the same kinds of data as computing PDSI.
Dear Doug
Thank you for this interesting question. Please find the following link to a study where PHDI was used for paleo climate reconstruction. The authors might be able to give more information on advantages and disadvantages in using this index for such analyses:
https://www.ncei.noaa.gov/access/paleo-search/study/16456
Best regards
IDMP TSU
Dear Sir/Madam,
Hi, recently, I built a GRACE-based hydrological drought index from 2002 to 2017 and I want to compare it with PHDI. So could you please provide the data at a global scale if the data has covered the period of 2002-2017 or MatLab code for me to calculate PHDI by myself? Thank you very much in advance.
Best wishes, Aihong
Is there any one who can help me?
Dear Temesgen Mekuriaw
You can pose your question related to the PHDI in this thread and we will respond to you. If you have a more general drought-related question, you can submit it following this link: https://www.droughtmanagement.info/ask/ask-form/.
Best regards
IDMP team
Seeking PHDI data for Europe and Argentina if possible.
Dear Kendra,
We will check with our partners whether this data exists.
IDMP
Hello,
Just checking the status of this request. Is there anywhere else I could be looking?
what are the hydro logical meteorological agricultural drought indicators & indices ?
Dear Temesgen,
Please take a look at the online Handbook on Drought Indicators and Indices on this website and the PDF version at this link:
https://www.droughtmanagement.info/find/guidelines-tools/handbook-drought-indicators-and-indices/
IDMP Team
i am Ms c student in engineering hydrology , now i fishiness the course ,but i can not do the thesis/paper ..due to lack of reference books ..research paper and software related to my topic ((((( ASSESSMENT AND EVALUATION OF HYDRO LOGICAL DROUGHT ANALYSIS USING DROUGHT INDEX, IN THE UPPER BLUE NILE BASIN))))))))……so i need from you is that
1, related books and references ,research papers with detail explained form
2, software’s …thank you for fast response…!!!!!!
Dear Temesgen,
In the Indices and Indicator Section of the Handbook and on the website, there are a list of References and Resources available. For example, for the PHDI the code can be found at http://onlinelibrary.wiley.com/doi/10.1002/wrcr.20342/pdf . I will see if there is online version of the reference.
IDMP
Also, please see the following link to the PDHI reference. We have also added the link above.
https://www.ncdc.noaa.gov/temp-and-precip/drought/docs/palmer.pdf
Best regards,
IDMP Team
i am a student in Msc in hydrology enginering…so as much as possible please help me..a want your hand
Dear Temesgen, Please be more specific with your request. We will send you an email.
IDMP
please send your work on hydrlogical drought analysis based on different drought analysis indce pdf in detail