Modal Behavior of Hemispheric Sea Ice Covers
Recent papers have described 18-year trends and annual oscillations in the Arctic and Antarctic sea ice extents, areas, and enclosed open water areas based on a newly-formulated 18.2-year ice concentration time series. This time series includes data for the entire Arctic and Antarctic ice covers, as...
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ftnasantrs:oai:casi.ntrs.nasa.gov:19980237551 2023-05-15T14:03:46+02:00 Modal Behavior of Hemispheric Sea Ice Covers Shen, Zheng Gloersen, Per Huang, Norden Unclassified, Unlimited, Publicly available 1998 application/pdf http://hdl.handle.net/2060/19980237551 unknown Document ID: 19980237551 http://hdl.handle.net/2060/19980237551 No Copyright CASI Oceanography 1998 ftnasantrs 2015-03-15T02:59:35Z Recent papers have described 18-year trends and annual oscillations in the Arctic and Antarctic sea ice extents, areas, and enclosed open water areas based on a newly-formulated 18.2-year ice concentration time series. This time series includes data for the entire Arctic and Antarctic ice covers, as well as for previously defined subregions consisting of 5 sectors in the Antarctic and 9 regions in the Arctic. It was obtained by fine-tuning the sea ice algorithm tie points individually for each of the four sensors used to acquire the data. In this paper, we extend these analyses to an examination of the intrinsic modes of these time series, obtained by means of Empirical Mode Decomposition, with emphasis on periodicities greater than the annual cycle. Quasibiennial and quasiquadrennial oscillations observed with a different technique and reported earlier for the first 8.8 years of this time series were also observed in the present series. However, the intrinsic modes were not monochromatic; they feature frequency as well as amplitude modulation within their respective frequency bands. Modal periods of up to 18 years are observed, with important implications for the trend analyses published earlier. These results are compared with the oscillations in the Length-of-Day and North Atlantic Oscillation parameters similarly determined for the same 18.2-year period. Other/Unknown Material Antarc* Antarctic Arctic North Atlantic North Atlantic oscillation Sea ice NASA Technical Reports Server (NTRS) Antarctic Arctic The Antarctic |
institution |
Open Polar |
collection |
NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
unknown |
topic |
Oceanography |
spellingShingle |
Oceanography Shen, Zheng Gloersen, Per Huang, Norden Modal Behavior of Hemispheric Sea Ice Covers |
topic_facet |
Oceanography |
description |
Recent papers have described 18-year trends and annual oscillations in the Arctic and Antarctic sea ice extents, areas, and enclosed open water areas based on a newly-formulated 18.2-year ice concentration time series. This time series includes data for the entire Arctic and Antarctic ice covers, as well as for previously defined subregions consisting of 5 sectors in the Antarctic and 9 regions in the Arctic. It was obtained by fine-tuning the sea ice algorithm tie points individually for each of the four sensors used to acquire the data. In this paper, we extend these analyses to an examination of the intrinsic modes of these time series, obtained by means of Empirical Mode Decomposition, with emphasis on periodicities greater than the annual cycle. Quasibiennial and quasiquadrennial oscillations observed with a different technique and reported earlier for the first 8.8 years of this time series were also observed in the present series. However, the intrinsic modes were not monochromatic; they feature frequency as well as amplitude modulation within their respective frequency bands. Modal periods of up to 18 years are observed, with important implications for the trend analyses published earlier. These results are compared with the oscillations in the Length-of-Day and North Atlantic Oscillation parameters similarly determined for the same 18.2-year period. |
author |
Shen, Zheng Gloersen, Per Huang, Norden |
author_facet |
Shen, Zheng Gloersen, Per Huang, Norden |
author_sort |
Shen, Zheng |
title |
Modal Behavior of Hemispheric Sea Ice Covers |
title_short |
Modal Behavior of Hemispheric Sea Ice Covers |
title_full |
Modal Behavior of Hemispheric Sea Ice Covers |
title_fullStr |
Modal Behavior of Hemispheric Sea Ice Covers |
title_full_unstemmed |
Modal Behavior of Hemispheric Sea Ice Covers |
title_sort |
modal behavior of hemispheric sea ice covers |
publishDate |
1998 |
url |
http://hdl.handle.net/2060/19980237551 |
op_coverage |
Unclassified, Unlimited, Publicly available |
geographic |
Antarctic Arctic The Antarctic |
geographic_facet |
Antarctic Arctic The Antarctic |
genre |
Antarc* Antarctic Arctic North Atlantic North Atlantic oscillation Sea ice |
genre_facet |
Antarc* Antarctic Arctic North Atlantic North Atlantic oscillation Sea ice |
op_source |
CASI |
op_relation |
Document ID: 19980237551 http://hdl.handle.net/2060/19980237551 |
op_rights |
No Copyright |
_version_ |
1766274619266826240 |