The role of heavy rainfall in drought in Australia

Tess Parker; Ailie J.E. Gallant

doi:10.1016/j.wace.2022.100528

The role of heavy rainfall in drought in Australia

Tess Parker
, Ailie J.E. Gallant

School of Earth Atmosphere and Environment

Research output: Contribution to journal › Article › Research › peer-review

20 Citations (Scopus)

Abstract

Droughts are initiated and significantly maintained by precipitation deficits. This study demonstrates that meteorological droughts in Australia are strongly related to changes in the occurrence of heavy rainfall events. We use the standardised precipitation index to identify periods of drought onset, drought development, and recovery from drought. This method successfully identifies the major multi-year drought periods in Australia, which have major impacts on a range of sectors. We show that the occurrence of meteorological (i.e. precipitation-deficit) drought in Australia is regulated by changes in days of significant rainfall. Days with rainfall above 20 mm are responsible for a median of approximately 60% of the reduction in rainfall during drought development periods, and approximately 70% of the rainfall surplus during drought recovery periods. These changes in days of higher rainfall accumulation, which are the greatest contributors to the total reduction in rainfall during drought, equate to very few days per year of rainfall: less than 10 days/year equivalent for the majority of the continent. It is a reduction in these heavy, but infrequent rainfall days that results in a location being classified as in meteorological drought. Similarly, an above-average occurrence of such days will indicate a period of at least partial recovery from drought. Both the frequency of heavy rainfall days and their contribution to accumulated rainfall are demonstrated to be important. These results indicate that an investigation of the synoptic weather systems responsible for heavy rainfall days, as well as changes in the frequency of occurrence of these systems and their relative contributions to total rainfall, is necessary to advance the understanding of drought in Australia.

Original language	English
Article number	100528
Number of pages	13
Journal	Weather and Climate Extremes
Volume	38
DOIs	https://doi.org/10.1016/j.wace.2022.100528
Publication status	Published - Dec 2022

Keywords

Australia
Drought
Rainfall

Access to Document

10.1016/j.wace.2022.100528Licence: CC BY-NC-ND

Cite this

@article{c09730c7203e4322aba1ae67935513f4,

title = "The role of heavy rainfall in drought in Australia",

abstract = "Droughts are initiated and significantly maintained by precipitation deficits. This study demonstrates that meteorological droughts in Australia are strongly related to changes in the occurrence of heavy rainfall events. We use the standardised precipitation index to identify periods of drought onset, drought development, and recovery from drought. This method successfully identifies the major multi-year drought periods in Australia, which have major impacts on a range of sectors. We show that the occurrence of meteorological (i.e. precipitation-deficit) drought in Australia is regulated by changes in days of significant rainfall. Days with rainfall above 20 mm are responsible for a median of approximately 60\% of the reduction in rainfall during drought development periods, and approximately 70\% of the rainfall surplus during drought recovery periods. These changes in days of higher rainfall accumulation, which are the greatest contributors to the total reduction in rainfall during drought, equate to very few days per year of rainfall: less than 10 days/year equivalent for the majority of the continent. It is a reduction in these heavy, but infrequent rainfall days that results in a location being classified as in meteorological drought. Similarly, an above-average occurrence of such days will indicate a period of at least partial recovery from drought. Both the frequency of heavy rainfall days and their contribution to accumulated rainfall are demonstrated to be important. These results indicate that an investigation of the synoptic weather systems responsible for heavy rainfall days, as well as changes in the frequency of occurrence of these systems and their relative contributions to total rainfall, is necessary to advance the understanding of drought in Australia.",

keywords = "Australia, Drought, Rainfall",

author = "Tess Parker and Gallant, \{Ailie J.E.\}",

note = "Funding Information: TP and AG are supported by funding from the Australian Research Council Centre of Excellence for Climate Extremes ( CE170100023 ). Publisher Copyright: {\textcopyright} 2022 The Author(s)",

year = "2022",

month = dec,

doi = "10.1016/j.wace.2022.100528",

language = "English",

volume = "38",

journal = "Weather and Climate Extremes",

issn = "2212-0947",

publisher = "Elsevier BV",

}

TY - JOUR

T1 - The role of heavy rainfall in drought in Australia

AU - Parker, Tess

AU - Gallant, Ailie J.E.

PY - 2022/12

Y1 - 2022/12

N2 - Droughts are initiated and significantly maintained by precipitation deficits. This study demonstrates that meteorological droughts in Australia are strongly related to changes in the occurrence of heavy rainfall events. We use the standardised precipitation index to identify periods of drought onset, drought development, and recovery from drought. This method successfully identifies the major multi-year drought periods in Australia, which have major impacts on a range of sectors. We show that the occurrence of meteorological (i.e. precipitation-deficit) drought in Australia is regulated by changes in days of significant rainfall. Days with rainfall above 20 mm are responsible for a median of approximately 60% of the reduction in rainfall during drought development periods, and approximately 70% of the rainfall surplus during drought recovery periods. These changes in days of higher rainfall accumulation, which are the greatest contributors to the total reduction in rainfall during drought, equate to very few days per year of rainfall: less than 10 days/year equivalent for the majority of the continent. It is a reduction in these heavy, but infrequent rainfall days that results in a location being classified as in meteorological drought. Similarly, an above-average occurrence of such days will indicate a period of at least partial recovery from drought. Both the frequency of heavy rainfall days and their contribution to accumulated rainfall are demonstrated to be important. These results indicate that an investigation of the synoptic weather systems responsible for heavy rainfall days, as well as changes in the frequency of occurrence of these systems and their relative contributions to total rainfall, is necessary to advance the understanding of drought in Australia.

AB - Droughts are initiated and significantly maintained by precipitation deficits. This study demonstrates that meteorological droughts in Australia are strongly related to changes in the occurrence of heavy rainfall events. We use the standardised precipitation index to identify periods of drought onset, drought development, and recovery from drought. This method successfully identifies the major multi-year drought periods in Australia, which have major impacts on a range of sectors. We show that the occurrence of meteorological (i.e. precipitation-deficit) drought in Australia is regulated by changes in days of significant rainfall. Days with rainfall above 20 mm are responsible for a median of approximately 60% of the reduction in rainfall during drought development periods, and approximately 70% of the rainfall surplus during drought recovery periods. These changes in days of higher rainfall accumulation, which are the greatest contributors to the total reduction in rainfall during drought, equate to very few days per year of rainfall: less than 10 days/year equivalent for the majority of the continent. It is a reduction in these heavy, but infrequent rainfall days that results in a location being classified as in meteorological drought. Similarly, an above-average occurrence of such days will indicate a period of at least partial recovery from drought. Both the frequency of heavy rainfall days and their contribution to accumulated rainfall are demonstrated to be important. These results indicate that an investigation of the synoptic weather systems responsible for heavy rainfall days, as well as changes in the frequency of occurrence of these systems and their relative contributions to total rainfall, is necessary to advance the understanding of drought in Australia.

KW - Australia

KW - Drought

KW - Rainfall

UR - https://www.scopus.com/pages/publications/85142800857

U2 - 10.1016/j.wace.2022.100528

DO - 10.1016/j.wace.2022.100528

M3 - Article

AN - SCOPUS:85142800857

SN - 2212-0947

VL - 38

JO - Weather and Climate Extremes

JF - Weather and Climate Extremes

M1 - 100528

ER -

The role of heavy rainfall in drought in Australia

Abstract

Keywords

Access to Document

Other files and links

ARC Centre of Excellence for Climate Extremes

Cite this

The role of heavy rainfall in drought in Australia

Abstract

Keywords

Access to Document

Other files and links

Projects

ARC Centre of Excellence for Climate Extremes

Cite this