The greening and wetting of the sahel have leveled off since about 1999 in relation to SST
The Sahel, a semi-arid climatic zone with highly seasonal and erratic rainfall, experienced severe droughts in the 1970s and 1980s. Based on remote sensing vegetation indices since early 1980, a clear greening trend is found, which can be attributed to the recovery of contemporaneous precipitation....
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Language: | English |
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2020
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Online Access: | https://research.vu.nl/en/publications/e2c3f859-b836-4b0a-893e-268b44f9221f https://doi.org/10.3390/RS12172723 https://hdl.handle.net/1871.1/e2c3f859-b836-4b0a-893e-268b44f9221f http://www.scopus.com/inward/record.url?scp=85090588270&partnerID=8YFLogxK http://www.scopus.com/inward/citedby.url?scp=85090588270&partnerID=8YFLogxK |
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ftvuamstcris:oai:research.vu.nl:publications/e2c3f859-b836-4b0a-893e-268b44f9221f 2024-09-15T18:23:56+00:00 The greening and wetting of the sahel have leveled off since about 1999 in relation to SST Chen, Tiexi Zhou, Shengjie Liang, Chuanzhuang Hagan, Daniel Fiifi Tawia Zeng, Ning Wang, Jun Shi, Tingting Chen, Xin Dolman, A. J. 2020-09 https://research.vu.nl/en/publications/e2c3f859-b836-4b0a-893e-268b44f9221f https://doi.org/10.3390/RS12172723 https://hdl.handle.net/1871.1/e2c3f859-b836-4b0a-893e-268b44f9221f http://www.scopus.com/inward/record.url?scp=85090588270&partnerID=8YFLogxK http://www.scopus.com/inward/citedby.url?scp=85090588270&partnerID=8YFLogxK eng eng https://research.vu.nl/en/publications/e2c3f859-b836-4b0a-893e-268b44f9221f info:eu-repo/semantics/openAccess Chen , T , Zhou , S , Liang , C , Hagan , D F T , Zeng , N , Wang , J , Shi , T , Chen , X & Dolman , A J 2020 , ' The greening and wetting of the sahel have leveled off since about 1999 in relation to SST ' , Remote Sensing , vol. 12 , no. 17 , 2723 , pp. 1-17 . https://doi.org/10.3390/RS12172723 Greening Precipitation Sahel Sea surface temperature Vegetation Wetting /dk/atira/pure/sustainabledevelopmentgoals/life_below_water name=SDG 14 - Life Below Water article 2020 ftvuamstcris https://doi.org/10.3390/RS12172723 2024-08-22T00:13:34Z The Sahel, a semi-arid climatic zone with highly seasonal and erratic rainfall, experienced severe droughts in the 1970s and 1980s. Based on remote sensing vegetation indices since early 1980, a clear greening trend is found, which can be attributed to the recovery of contemporaneous precipitation. Here, we present an analysis using long-term leaf area index (LAI), precipitation, and sea surface temperature (SST) records to investigate their trends and relationships. LAI and precipitation show a significant positive trend between 1982 and 2016, at 1.72 × 10 -3 yr -1 (p < 0.01) and 4.63 mm yr -1 (p < 0.01), respectively. However, a piecewise linear regression approach indicates that the trends in both LAI and precipitation are not continuous throughout the 35 year period. In fact, both the greening and wetting of the Sahel have been leveled off (pause of rapid growth) since about 1999. The trends of LAI and precipitation between 1982 and 1999 and 1999-2016 are 4.25 × 10 -3 yr -1 to - 0.27 × 10 -3 yr -1 , and 9.72 mm yr -1 to 2.17 mm yr -1 , respectively. These declines in trends are further investigated using an SST index, which is composed of the SSTs of the Mediterranean Sea, the subtropical North Atlantic, and the global tropical oceans. Causality analysis based on information flow theory affirms this precipitation stabilization between 2003 and 2014. Our results highlight that both the greening and the wetting of the Sahel have been leveled off, a feature that was previously hidden in the apparent long-lasting greening and wetting records since the extreme low values in the 1980s. Article in Journal/Newspaper North Atlantic Vrije Universiteit Amsterdam (VU): Research Portal Remote Sensing 12 17 2723 |
institution |
Open Polar |
collection |
Vrije Universiteit Amsterdam (VU): Research Portal |
op_collection_id |
ftvuamstcris |
language |
English |
topic |
Greening Precipitation Sahel Sea surface temperature Vegetation Wetting /dk/atira/pure/sustainabledevelopmentgoals/life_below_water name=SDG 14 - Life Below Water |
spellingShingle |
Greening Precipitation Sahel Sea surface temperature Vegetation Wetting /dk/atira/pure/sustainabledevelopmentgoals/life_below_water name=SDG 14 - Life Below Water Chen, Tiexi Zhou, Shengjie Liang, Chuanzhuang Hagan, Daniel Fiifi Tawia Zeng, Ning Wang, Jun Shi, Tingting Chen, Xin Dolman, A. J. The greening and wetting of the sahel have leveled off since about 1999 in relation to SST |
topic_facet |
Greening Precipitation Sahel Sea surface temperature Vegetation Wetting /dk/atira/pure/sustainabledevelopmentgoals/life_below_water name=SDG 14 - Life Below Water |
description |
The Sahel, a semi-arid climatic zone with highly seasonal and erratic rainfall, experienced severe droughts in the 1970s and 1980s. Based on remote sensing vegetation indices since early 1980, a clear greening trend is found, which can be attributed to the recovery of contemporaneous precipitation. Here, we present an analysis using long-term leaf area index (LAI), precipitation, and sea surface temperature (SST) records to investigate their trends and relationships. LAI and precipitation show a significant positive trend between 1982 and 2016, at 1.72 × 10 -3 yr -1 (p < 0.01) and 4.63 mm yr -1 (p < 0.01), respectively. However, a piecewise linear regression approach indicates that the trends in both LAI and precipitation are not continuous throughout the 35 year period. In fact, both the greening and wetting of the Sahel have been leveled off (pause of rapid growth) since about 1999. The trends of LAI and precipitation between 1982 and 1999 and 1999-2016 are 4.25 × 10 -3 yr -1 to - 0.27 × 10 -3 yr -1 , and 9.72 mm yr -1 to 2.17 mm yr -1 , respectively. These declines in trends are further investigated using an SST index, which is composed of the SSTs of the Mediterranean Sea, the subtropical North Atlantic, and the global tropical oceans. Causality analysis based on information flow theory affirms this precipitation stabilization between 2003 and 2014. Our results highlight that both the greening and the wetting of the Sahel have been leveled off, a feature that was previously hidden in the apparent long-lasting greening and wetting records since the extreme low values in the 1980s. |
format |
Article in Journal/Newspaper |
author |
Chen, Tiexi Zhou, Shengjie Liang, Chuanzhuang Hagan, Daniel Fiifi Tawia Zeng, Ning Wang, Jun Shi, Tingting Chen, Xin Dolman, A. J. |
author_facet |
Chen, Tiexi Zhou, Shengjie Liang, Chuanzhuang Hagan, Daniel Fiifi Tawia Zeng, Ning Wang, Jun Shi, Tingting Chen, Xin Dolman, A. J. |
author_sort |
Chen, Tiexi |
title |
The greening and wetting of the sahel have leveled off since about 1999 in relation to SST |
title_short |
The greening and wetting of the sahel have leveled off since about 1999 in relation to SST |
title_full |
The greening and wetting of the sahel have leveled off since about 1999 in relation to SST |
title_fullStr |
The greening and wetting of the sahel have leveled off since about 1999 in relation to SST |
title_full_unstemmed |
The greening and wetting of the sahel have leveled off since about 1999 in relation to SST |
title_sort |
greening and wetting of the sahel have leveled off since about 1999 in relation to sst |
publishDate |
2020 |
url |
https://research.vu.nl/en/publications/e2c3f859-b836-4b0a-893e-268b44f9221f https://doi.org/10.3390/RS12172723 https://hdl.handle.net/1871.1/e2c3f859-b836-4b0a-893e-268b44f9221f http://www.scopus.com/inward/record.url?scp=85090588270&partnerID=8YFLogxK http://www.scopus.com/inward/citedby.url?scp=85090588270&partnerID=8YFLogxK |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Chen , T , Zhou , S , Liang , C , Hagan , D F T , Zeng , N , Wang , J , Shi , T , Chen , X & Dolman , A J 2020 , ' The greening and wetting of the sahel have leveled off since about 1999 in relation to SST ' , Remote Sensing , vol. 12 , no. 17 , 2723 , pp. 1-17 . https://doi.org/10.3390/RS12172723 |
op_relation |
https://research.vu.nl/en/publications/e2c3f859-b836-4b0a-893e-268b44f9221f |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.3390/RS12172723 |
container_title |
Remote Sensing |
container_volume |
12 |
container_issue |
17 |
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2723 |
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1810464225350385664 |