Is solar variability reflected in the Nile River?
We investigate the possibility that solar variability influences North African climate by using annual records of the water level of the Nile collected in 622–1470 A.D. The time series of these records are nonstationary, in that the amplitudes and frequencies of the quasi-periodic variations are tim...
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ftcaltechauth:oai:authors.library.caltech.edu:48785 2023-05-15T17:33:33+02:00 Is solar variability reflected in the Nile River? Ruzmaikin, Alexander Feynman, Joan Yung, Yuk L. 2006-11-16 application/pdf https://authors.library.caltech.edu/48785/ https://authors.library.caltech.edu/48785/1/jgrd13171.pdf https://resolver.caltech.edu/CaltechAUTHORS:20140821-154600521 en eng American Geophysical Union https://authors.library.caltech.edu/48785/1/jgrd13171.pdf Ruzmaikin, Alexander and Feynman, Joan and Yung, Yuk L. (2006) Is solar variability reflected in the Nile River? Journal of Geophysical Research D, 111 (D21). Art. No. D21114. ISSN 0148-0227. doi:10.1029/2006JD007462. https://resolver.caltech.edu/CaltechAUTHORS:20140821-154600521 <https://resolver.caltech.edu/CaltechAUTHORS:20140821-154600521> other Article PeerReviewed 2006 ftcaltechauth 2021-11-11T18:59:18Z We investigate the possibility that solar variability influences North African climate by using annual records of the water level of the Nile collected in 622–1470 A.D. The time series of these records are nonstationary, in that the amplitudes and frequencies of the quasi-periodic variations are time-dependent. We apply the Empirical Mode Decomposition technique especially designed to deal with such time series. We identify two characteristic timescales in the records that may be linked to solar variability: a period of about 88 years and one exceeding 200 years. We show that these timescales are present in the number of auroras reported per decade in the Northern Hemisphere at the same time. The 11-year cycle is seen in the Nile's high-water level variations, but it is damped in the low-water anomalies. We suggest a possible physical link between solar variability and the low-frequency variations of the Nile water level. This link involves the influence of solar variability on the atmospheric Northern Annual Mode and on its North Atlantic Ocean and Indian Ocean patterns that affect the rainfall over the sources of the Nile in eastern equatorial Africa. Article in Journal/Newspaper North Atlantic Caltech Authors (California Institute of Technology) Indian |
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English |
description |
We investigate the possibility that solar variability influences North African climate by using annual records of the water level of the Nile collected in 622–1470 A.D. The time series of these records are nonstationary, in that the amplitudes and frequencies of the quasi-periodic variations are time-dependent. We apply the Empirical Mode Decomposition technique especially designed to deal with such time series. We identify two characteristic timescales in the records that may be linked to solar variability: a period of about 88 years and one exceeding 200 years. We show that these timescales are present in the number of auroras reported per decade in the Northern Hemisphere at the same time. The 11-year cycle is seen in the Nile's high-water level variations, but it is damped in the low-water anomalies. We suggest a possible physical link between solar variability and the low-frequency variations of the Nile water level. This link involves the influence of solar variability on the atmospheric Northern Annual Mode and on its North Atlantic Ocean and Indian Ocean patterns that affect the rainfall over the sources of the Nile in eastern equatorial Africa. |
format |
Article in Journal/Newspaper |
author |
Ruzmaikin, Alexander Feynman, Joan Yung, Yuk L. |
spellingShingle |
Ruzmaikin, Alexander Feynman, Joan Yung, Yuk L. Is solar variability reflected in the Nile River? |
author_facet |
Ruzmaikin, Alexander Feynman, Joan Yung, Yuk L. |
author_sort |
Ruzmaikin, Alexander |
title |
Is solar variability reflected in the Nile River? |
title_short |
Is solar variability reflected in the Nile River? |
title_full |
Is solar variability reflected in the Nile River? |
title_fullStr |
Is solar variability reflected in the Nile River? |
title_full_unstemmed |
Is solar variability reflected in the Nile River? |
title_sort |
is solar variability reflected in the nile river? |
publisher |
American Geophysical Union |
publishDate |
2006 |
url |
https://authors.library.caltech.edu/48785/ https://authors.library.caltech.edu/48785/1/jgrd13171.pdf https://resolver.caltech.edu/CaltechAUTHORS:20140821-154600521 |
geographic |
Indian |
geographic_facet |
Indian |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
https://authors.library.caltech.edu/48785/1/jgrd13171.pdf Ruzmaikin, Alexander and Feynman, Joan and Yung, Yuk L. (2006) Is solar variability reflected in the Nile River? Journal of Geophysical Research D, 111 (D21). Art. No. D21114. ISSN 0148-0227. doi:10.1029/2006JD007462. https://resolver.caltech.edu/CaltechAUTHORS:20140821-154600521 <https://resolver.caltech.edu/CaltechAUTHORS:20140821-154600521> |
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other |
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1766132104801812480 |