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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ftnasajpl:oai:trs.jpl.nasa.gov:2014/40231 2023-05-15T17:33:24+02:00 Is solar variability reflected in the Nile River? Ruzmaikin, Alexander Feynman, Joan Yung, Yuk L. 2007-05-31T21:23:24Z 498564 bytes application/pdf http://hdl.handle.net/2014/40231 en_US eng American Geophysical Union Journal Of Geophysical Research, Vol. 111, D21114, doi:10.1029/2006JD007462, 2006 06-1989 http://hdl.handle.net/2014/40231 climate variability solar variability Article 2007 ftnasajpl https://doi.org/10.1029/2006JD007462 2021-12-23T13:17:25Z 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. NASA/JPL Article in Journal/Newspaper North Atlantic JPL Technical Report Server Indian Journal of Geophysical Research 111 D21 |
institution |
Open Polar |
collection |
JPL Technical Report Server |
op_collection_id |
ftnasajpl |
language |
English |
topic |
climate variability solar variability |
spellingShingle |
climate variability solar variability Ruzmaikin, Alexander Feynman, Joan Yung, Yuk L. Is solar variability reflected in the Nile River? |
topic_facet |
climate variability solar variability |
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. NASA/JPL |
format |
Article in Journal/Newspaper |
author |
Ruzmaikin, Alexander Feynman, Joan Yung, Yuk L. |
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 |
2007 |
url |
http://hdl.handle.net/2014/40231 |
geographic |
Indian |
geographic_facet |
Indian |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
Journal Of Geophysical Research, Vol. 111, D21114, doi:10.1029/2006JD007462, 2006 06-1989 http://hdl.handle.net/2014/40231 |
op_doi |
https://doi.org/10.1029/2006JD007462 |
container_title |
Journal of Geophysical Research |
container_volume |
111 |
container_issue |
D21 |
_version_ |
1766131906254995456 |