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Drought

From Wikipedia
drought
condition, natural disaster
Subclass ofmeteorological disaster, extreme weather event, dry spell Edit
Facet givemeteorology Edit
Has causehuman overpopulation Edit
Has contributing factorClimate change Edit
Get characteristicabsence Edit
Relates to sustainable development goal, target or indicatorTarget 2.4 of the Sustainable Development Goals Edit

A drought be a period of drier-than-normal conditions.[1]: 1157  A drought fit last for days, months anaa years. Drought often get large impacts on de ecosystems den agriculture of affected regions, wey e dey cause harm to de locale economy.[2][3] Annual dry seasons insyd de tropics significantly increase de chances of a drought developing, plus subsequent increased wildfire risks.[4] Heat wave fit significantly worsen drought conditions by increasing evapotranspiration.[5] Dis dey dry out forests den oda vegetation, den increases de amount of fuel for wildfires.[4][6]

Drought be a recurring feature of de climate insyd most parts of de world, becoming more extreme den less predictable secof climate change, wich dendrochronological studies date back to 1900. Der be three kinds of drought effects, environmental, economic den social. Environmental effects include de drying of wetlands, more den larger wildfires, loss of biodiversity.

Economic impacts of drought result secof negative disruptions to agriculture den livestock farming (causing food insecurity), forestry, public water supplies, river navigation (secof e.g.: lower water levels), electric power supply (by affecting hydropower systems) den impacts on human health.[7]

Social den health costs include de negative effect on de health of people directly exposed to dis phenomenon (excessive heat waves), high food costs, stress wey failed harvests cause, water scarcity, etc. Drought sanso fi lead to increased air pollution secof increased dust concentrations den wildfires.[8] Prolonged droughts dey cause mass migrations den humanitarian crisis.[9][10]

Examples for regions plus increased drought risks be de Amazon basin, Australia, de Sahel region den India. For example, insyd 2005, parts of de Amazon basin experience de worst drought insyd 100 years.[11][12] Australia fi experience more severe droughts den wey e cam be more frequent insyd de future, a government-commissioned report say on July 6, 2008.[13] De long Australian Millennial drought break insyd 2010. De 2020-2022 Horn of Africa drought surpass de severe drought insyd 2010–2011 insyd both duration den severity.[14][15]

Throughout history, humans usually view droughts as disasters secof de impact on food availability den de rest of society. People view drought as a natural disaster anaa as something wey human activity influence, anaa as a result of supernatural forces.

Definition

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Fields outsyd Benambra, Australia wey dey suffer from drought insyd 2006.

De IPCC Sixth Assessment Report dey define a drought simply as "drier dan normal conditions".[1]: 1157  Dis dey mean say a drought be "a moisture deficit relative to de average water availability at a given location den season".[1]: 1157 

According to National Integrated Drought Information System, a multi-agency partnership, drought be generally defined as "a deficiency of precipitation over an extended period of time (usually a season anaa more), resulting insyd a water shortage". De National Weather Service office of de NOAA defines drought as "a deficiency of moisture dat results insyd adverse impacts on people, animals, anaa vegetation over a sizeable area".[16]

Drought be a complex phenomenon − wey dey relate to de absence of water − wich be difficult to monitor den define.[17] By de early 1980s, over 150 definitions of "drought" already be published.[18] De range of definitions dey reflect differences insyd regions, needs, den disciplinary approaches.

Categories

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Der be three major categories of drought wey dey base on wer insyd de water cycle de moisture deficit dey occur: meteorological drought, hydrological drought, den agricultural anaa ecological drought.[1]: 1157  A meteorological drought dey occur secof lack of precipitation. A hydrological drought be related to low runoff, streamflow, den reservoir den groundwater storage.[19] An agricultural anaa ecological drought dey cause plant stress from a combination of evaporation den low soil moisture.[1]: 1157  Some organizations add anoda category: socioeconomic drought dey occur wen de demand for an economic good exceed supply as a result of a weather-related shortfall insyd water supply.[17][18] De socioeconomic drought be a similar concept to water scarcity.

De different categories of droughts get different causes buh similar effects:

  1. Meteorological drought dey occur wen der be a prolonged time plus less than average precipitation.[20] Meteorological drought usually dey precede de oda kinds of drought.[21] As a drought persists, de conditions wey dey surround am gradually worsen den ein impact on de local population gradually increase.
  2. Hydrological drought dey happen wen water reserves available insyd sources such as aquifers, lakes den reservoirs fall below average anaa a locally significant threshold. Hydrological drought dey tend to present more slowly secof e dey involve stored water dat be used buh no be replenished. Secof de close interaction plus water use, dis type of drought fit be heavily influenced by water management. Both positive den negative human influences be discovered den strategic water management strategies seem key to mitigate drought impact.[22][23] Like agricultural droughts, hydrological droughts fit be triggered by more dan just a loss of rainfall. For instance, around 2007 na dem award Kazakhstan a large amount of money by de World Bank to restore water wey be diverted to oda nations from de Aral Sea under Soviet rule.[24] Similar circumstances sanso place dem largest lake, Balkhash, at risk of completely drying out.[25]
  3. Agricultural anaa ecological droughts dey affect crop production anaa ecosystems in general. Dis condition sanso fi arise independently from any change insyd precipitation levels wen either increased irrigation anaa soil conditions den erosion triggered by poorly planned agricultural endeavors cause a shortfall insyd water available to de crops.

Indices den monitoring

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Percent of U.S. experiencing drought intensity of at least level D2 (severe drought), during de weeks of 2000 to 2024.

Several indices be defined to quantify den monitor drought at different spatial den temporal scales. A key property of drought indices be dema spatial comparability, wey dem for be statistically robust.[26] Drought indices dey include:[26]

  • Palmer drought index (dem sam times call de Palmer drought severity index (PDSI)): a regional drought index commonly used for monitoring drought events den studying areal extent den severity of drought episodes.[27] De index dey use precipitation den temperature data to study moisture supply den demand wey dey use a simple water balance model.[27][28][29]
  • Keetch-Byram Drought Index: an index dat be calculated based on rainfall, air temperature, den oda meteorological factors.[30]
  • Standardized precipitation index (SPI): E be computed based on precipitation, wich dey make am a simple den easy-to-apply indicator for monitoring den prediction of droughts insyd different parts of de world. De World Meteorological Organization dey recommend dis index for identifying den monitoring meteorological droughts insyd different climates den time periods.[26]
  • Standardized Precipitation Index (SPEI): a multiscalar drought index based on climatic data. De SPEI sanso dey account for de role of de increased atmospheric evaporative demand on drought severity.[26] Evaporative demand be particularly dominant during periods of precipitation deficit. De SPEI calculation dey require long-term den high-quality precipitation den atmospheric evaporative demand datasets. Dese fi be obtained from ground stations anaa gridded data based on reanalysis as well as satellite den multi-source datasets.[26]
  • Indices related to vegetation: root-zone soil moisture, vegetation condition index (VDI) den vegetation health index (VHI). De VCI den VHI be computed based on vegetation indices such as de normalized difference vegetation index (NDVI) den temperature datasets.[26]
  • Deciles index
  • Standardized runoff index

High-resolution drought information dey help to better assess de spatial den temporal changes den variability insyd drought duration, severity, den magnitude at a much finer scale. Dis dey support de development of site-specific adaptation measures.[26]

De application of multiple indices wey dey use different datasets help to better manage den monitor droughts dan using a single dataset, Dis be particularly de case insyd regions of de world wer enough data no be available such as Africa den South America. Using a single dataset fit be limiting, as e no fi capture de full spectrum of drought characteristics den impacts.[26]

Careful monitoring of moisture levels fit sanso help predict increased risk for wildfires.

References

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  1. 1 2 3 4 5 Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, and O. Zolina, 2021: Water Cycle Changes Archived 2022-09-29 at the Wayback Machine. In Climate Change 2021: The Physical Science Basis. Contribution of Working Group I  to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Masson-Delmotte, V., P. Zhai, A. Pirani, S.L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. Matthews, T.K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, and B. Zhou (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 1055–1210, doi:10.1017/9781009157896.010.
  2. ↑ Living With Drought Archived 2007-02-18 at the Wayback Machine
  3. ↑ Australian Drought and Climate Change Archived 2018-07-26 at the Wayback Machine. Retrieved June 7th 2007.
  4. 1 2 Brando, Paulo M.; Paolucci, Lucas; Ummenhofer, Caroline C.; Ordway, Elsa M.; Hartmann, Henrik; Cattau, Megan E.; Rattis, Ludmila; Medjibe, Vincent; Coe, Michael T.; Balch, Jennifer (30 May 2019). "Droughts, Wildfires, and Forest Carbon Cycling: A Pantropical Synthesis". Annual Review of Earth and Planetary Sciences. 47 (1): 555–581. Bibcode:2019AREPS..47..555B. doi:10.1146/annurev-earth-082517-010235. ISSN 0084-6597.
  5. ↑ Merzdorf, Jessica (July 9, 2019). "A Drier Future Sets the Stage for More Wildfires". Climate Change: Vital Signs of the Planet. NASA.
  6. ↑ Hartmann, Henrik; Bastos, Ana; Das, Adrian J.; Esquivel-Muelbert, Adriane; Hammond, William M.; Martínez-Vilalta, Jordi; McDowell, Nate G.; Powers, Jennifer S.; Pugh, Thomas A.M.; Ruthrof, Katinka X.; Allen, Craig D. (20 May 2022). "Climate Change Risks to Global Forest Health: Emergence of Unexpected Events of Elevated Tree Mortality Worldwide". Annual Review of Plant Biology. 73 (1): 673–702. Bibcode:2022ARPB...73..673H. doi:10.1146/annurev-arplant-102820-012804. ISSN 1543-5008. PMID 35231182.
  7. ↑ Fleming-Muñoz, David A.; Whitten, Stuart; Bonnett, Graham D. (28 June 2023). "The economics of drought: A review of impacts and costs". Australian Journal of Agricultural and Resource Economics. 67 (4): 501–523. doi:10.1111/1467-8489.12527. ISSN 1364-985X.
  8. ↑ Stanke, Carla; Kerac, Marko; Prudhomme, Christel; Medlock, Jolyon; Murray, Virginia (2013-06-05). "Health Effects of Drought: a Systematic Review of the Evidence". PLOS Currents. 5 ecurrents.dis.7a2cee9e980f91ad7697b570bcc4b004. doi:10.1371/currents.dis.7a2cee9e980f91ad7697b570bcc4b004 (inactive 20 April 2026). ISSN 2157-3999. PMC 3682759. PMID 23787891.{{cite journal}}: CS1 maint: DOI inactive as of April 2026 (link)
  9. ↑ Stanke, C; Kerac, M; Prudhomme, C; Medlock, J; Murray, V (5 June 2013). "Health effects of drought: a systematic review of the evidence". PLOS Currents. 5. doi:10.1371/currents.dis.7a2cee9e980f91ad7697b570bcc4b004 (inactive 20 April 2026). PMC 3682759. PMID 23787891.{{cite journal}}: CS1 maint: DOI inactive as of April 2026 (link)
  10. ↑ Bellizzi, Saverio; Lane, Chris; Elhakim, Mohamed; Nabeth, Pierre (12 November 2020). "Health consequences of drought in the WHO Eastern Mediterranean Region: hotspot areas and needed actions". Environmental Health. 19 (1): 114. Bibcode:2020EnvHe..19..114B. doi:10.1186/s12940-020-00665-z. ISSN 1476-069X. PMC 7659048. PMID 33183302.
  11. ↑ "Amazon Drought Worst in 100 Years". ens-newswire.com. Archived from the original on 2019-11-15. Retrieved 5 November 2017.
  12. ↑ "Drought Threatens Amazon Basin". www.commondreams.org. Archived from the original on 2013-05-27. Retrieved 2026-06-26.
  13. ↑ "Australia faces worse, more frequent droughts: study". U.S. (in American English). Archived from the original on 2023-07-16. Retrieved 2026-06-26.
  14. ↑ Dunne, Daisy (2022-10-26). "Analysis: Africa's unreported extreme weather in 2022 and climate change". Carbon Brief. Retrieved 2022-10-29.
  15. ↑ "Horn of Africa Drought: Regional Humanitarian Overview & Call to Action". ReliefWeb. 2022-09-21. Retrieved 2022-10-29.
  16. ↑ "Drought Basics". Drought.gov. NOAA National Integrated Drought Information System. Retrieved 2022-09-16.
  17. 1 2 "Definition of Drought". National Centers for Environmental Information. Retrieved 2022-09-16.
  18. 1 2 "Types of Drought". drought.unl.edu. National Drought Mitigation Center. Retrieved 2022-09-16.
  19. ↑ Van Loon, Anne F. (14 April 2015). "Hydrological drought explained". WIREs Water. 2 (4): 359–392. Bibcode:2015WIRWa...2..359V. doi:10.1002/wat2.1085. ISSN 2049-1948.
  20. ↑ Swain, S; et al. (2017). "Application of SPI, EDI and PNPI using MSWEP precipitation data over Marathwada, India". 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS). Vol. 2017. pp. 5505–5507. doi:10.1109/IGARSS.2017.8128250. ISBN 978-1-5090-4951-6. S2CID 26920225.
  21. ↑ "What is a Drought?" (PDF). National Oceanic and Atmospheric Administration. August 2006. Archived (PDF) from the original on 2022-10-09. Retrieved 2007-04-10.
  22. ↑ Van Loon, Anne F.; Stahl, Kerstin; Di Baldassarre, Giuliano; Clark, Julian; Rangecroft, Sally; Wanders, Niko; Gleeson, Tom; Van Dijk, Albert I. J. M.; Tallaksen, Lena M.; Hannaford, Jamie; Uijlenhoet, Remko; Teuling, Adriaan J.; Hannah, David M.; Sheffield, Justin; Svoboda, Mark (2016-09-08). "Drought in a human-modified world: reframing drought definitions, understanding, and analysis approaches". Hydrology and Earth System Sciences. 20 (9): 3631–3650. Bibcode:2016HESS...20.3631V. doi:10.5194/hess-20-3631-2016. hdl:1885/152821. ISSN 1027-5606.
  23. ↑ Wendt, Doris E.; Van Loon, Anne F.; Bloomfield, John P.; Hannah, David M. (2020-10-13). "Asymmetric impact of groundwater use on groundwater droughts". Hydrology and Earth System Sciences. 24 (10): 4853–4868. Bibcode:2020HESS...24.4853W. doi:10.5194/hess-24-4853-2020. ISSN 1027-5606.
  24. ↑ "Asia-Pacific – Dam project aims to save Aral Sea". BBC News. 2007-04-09.
  25. ↑ "Asia-Pacific – Kazakh lake 'could dry up'". BBC News. 2004-01-15.
  26. 1 2 3 4 5 6 7 8 Gebrechorkos, Solomon H.; Peng, Jian; Dyer, Ellen; Miralles, Diego G.; Vicente-Serrano, Sergio M.; Funk, Chris; Beck, Hylke E.; Asfaw, Dagmawi T.; Singer, Michael B.; Dadson, Simon J. (2023). "Global high-resolution drought indices for 1981–2022". Earth System Science Data. 15 (12): 5449–5466. Bibcode:2023ESSD...15.5449G. doi:10.5194/essd-15-5449-2023. hdl:10754/693396. ISSN 1866-3516. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License
  27. 1 2 Mishra, Ashok K.; Singh, Vijay P. (September 2010). "A review of drought concepts". Journal of Hydrology. 391 (1–2): 202–216. Bibcode:2010JHyd..391..202M. doi:10.1016/j.jhydrol.2010.07.012.
  28. ↑ Van Loon, Anne F. (July 2015). "Hydrological drought explained: Hydrological drought explained". Wiley Interdisciplinary Reviews: Water. 2 (4): 359–392. Bibcode:2015WIRWa...2..359V. doi:10.1002/wat2.1085.
  29. ↑ Liu, Yi; Ren, Liliang; Ma, Mingwei; Yang, Xiaoli; Yuan, Fei; Jiang, Shanhu (January 2016). "An insight into the Palmer drought mechanism based indices: comprehensive comparison of their strengths and limitations". Stochastic Environmental Research and Risk Assessment. 30 (1): 119–136. Bibcode:2016SERRA..30..119L. doi:10.1007/s00477-015-1042-4. ISSN 1436-3240.
  30. ↑ Keetch, John J.; Byram, George M. (1968). "A Drought Index for Forest Fire Control". Res. Pap. Se-38. Asheville, Nc: U.S. Department of Agriculture, Forest Service, Southeastern Forest Experiment Station. 35 P. 038. USDA Forest Service Southern Research Station. Retrieved August 11, 2016. (Date: 1968) Res. Paper SE-38. 32 pp. Asheville, NC: U.S. Department of Agriculture, Forest Service
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  • GIDMaPS Global Integrated Drought Monitoring and Prediction System, University of California, Irvine
Dem retrieve am from "https://gpe.wikipedia.org/w/index.php?title=Drought&oldid=105098"