Identification

Title

Uncertainties in drought from index and data selection

Abstract

This study compares various drought indices, the Palmer Drought Severity Index (PDSI), the Standardized Precipitation Evapotranspiration Index (SPEI), and the Standardized Precipitation Index (SPI), and the uncertainties in each to the input data from which they are derived. The abilities of the PDSI, SPEI, and SPI to capture drought periods are assessed through a comparison with soil moisture estimates from two generations of the Global Land Data Assimilation System (GLDAS). This comparison shows that the skill with which a drought index represents variations in soil moisture does not necessarily improve when evapotranspiration is included (i.e., PDSI/SPEI rather than SPI), though this depends on location and the time scale of the drought. The differences in the abilities of the drought indices to represent soil moisture are also compared to the magnitude of the uncertainty in each index arising from the choice of input data. In many cases, the uncertainties in the variations of the PDSI, SPEI, and SPI to the choice of input data are larger in magnitude than the differences between the indices themselves, particularly when considering the dry tails of the distribution. The results show that no one drought index outperforms the others during drought conditions.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d7qj7mkw

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2020-09-27T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact