Nonstationary warm spell frequency analysis integrating climate variability and change with application to the Middle East

• Published in: Climate dynamics Vol. 53; no. 9-10; pp. 5329 - 5347
• Main Authors: Ouarda, Taha B. M. J., Charron, Christian, Kumar, Kondapalli Niranjan, Phanikumar, Devulapalli Venkata, Molini, Annalisa, Basha, Ghouse
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.11.2019; Springer; Springer Nature B.V
• Subjects: Aquatic resources; Atlantic Ocean; Atlantic Oscillation; Atmospheric circulation; Atmospheric circulation patterns; Atmospheric models; Canada; climate; Climate change; Climate cycles; Climate models; Climate variability; Climatic analysis; Climatic indexes; Climatology; Drought; Droughts; Duration; Earth and Environmental Science; Earth Sciences; Frequency analysis; Geophysics/Geodesy; Global climate; Global temperature changes; Goodness of fit; Hot weather; India; Mediation; Middle East; Observational studies; Oceanography; Oscillations; prediction; Statistical distributions; temperature; Temperature extremes; United Arab Emirates; Variability; Water resources; Water scarcity; Weather; Winter; Middle East; Canada; United Arab Emirates; India; Atlantic Ocean; Middle East; Climate change; Winter warm spell; Statistical distribution; Nonstationary model; Climate index; Frequency analysis; Natural climate variability
• ISSN: 0930-7575; 1432-0894
• DOI: 10.1007/s00382-019-04866-2

The Middle East can experience extended wintertime spells of exceptionally hot weather, which can result in prolonged droughts and have major impacts on the already scarce water resources of the region. Recent observational studies point at increasing trends in mean and extreme temperatures in the Middle East, while climate projections seem to indicate that, in a warming weather scenario, the frequency, intensity and duration of warm spells will increase. The nonstationary warm spell frequency analysis approach proposed herein allows considering both climate variability through global climatic oscillations and climate change signals. In this study, statistical distributions with parameters conditional on covariates representing time, to account for temporal trend, and climate indices are used to predict the frequency, duration and intensity of wintertime warm spells in the Middle East. Such models could find a large applicability in various fields of climate research, and in particular in the seasonal prediction of warm spell severity. Based on previous studies linking atmospheric circulation patterns in the Atlantic to extreme temperatures in the Middle East, we use as covariates two classic modes of ‘fast’ and ‘slow’ climatic variability in the Atlantic Ocean (i.e., the Northern Atlantic Oscillation and the Atlantic Multidecadal Oscillation respectively). Results indicate that the use of covariates improves the goodness-of-fit of models for all warm spell characteristics.