Werner Nel

Prof. Werner Nel


Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 June 2017 in Scientific Reports
Verified
Journal Article
Open access
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PPPanos Panagos
Panos Panagos
PBPasquale Borrelli
Pasquale Borrelli
KMKatrin Meusburger
Katrin Meusburger
BYBofu Yu
Bofu Yu
AKAndreas Klik
Andreas Klik
CBCristiano Ballabio
Cristiano Ballabio
The exposure of the Earth’s surface to the energetic input of rainfall is one of the key factors controlling water erosion. While water erosion is identified as the most serious cause of soil degradation globally, global patterns of rainfall erosivity remain poorly quantified and estimates have large uncertainties. This hampers the implementation of effective soil degradation mitigation and restoration strategies. Quantifying rainfall erosivity is challenging as it requires high temporal resolution(<30 min) and high fidelity rainfall recordings. We present the results of an extensive global data collection effort whereby we estimated rainfall erosivity for 3,625 stations covering 63 countries. This first ever Global Rainfall Erosivity Database was used to develop a global erosivity map at 30 arc-seconds(~1 km) based on a Gaussian Process Regression(GPR). Globally, the mean rainfall erosivity was estimated to be 2,190 MJ mm ha−1h−1yr−1, with the highest values in South America and the Caribbean countries, Central east Africa and South east Asia. The lowest values are mainly found in Canada, the Russian Federation, Northern Europe, Northern Africa and the Middle East. The tropical climate zone has the highest mean rainfall erosivity followed by the temperate whereas the lowest mean was estimated in the cold climate zone.

1 September 2014 in Quaternary Science Reviews
Verified
Journal Article
Open access
MBMichael J. Bentley
Michael J. Bentley
CCColm Ó Cofaigh
Colm Ó Cofaigh
JAJohn B. Anderson
John B. Anderson
HCHoward Conway
Howard Conway
BDBethan Davies
Bethan Davies
DZDan Zwartz
Dan Zwartz
A robust understanding of Antarctic Ice Sheet deglacial history since the Last Glacial Maximum is important in order to constrain ice sheet and glacial-isostatic adjustment models, and to explore the forcing mechanisms responsible for ice sheet retreat. Such understanding can be derived from a broad range of geological and glaciological datasets and recent decades have seen an upsurge in such data gathering around the continent and Sub-Antarctic islands. Here, we report a new synthesis of those datasets, based on an accompanying series of reviews of the geological data, organised by sector. We present a series of timeslice maps for 20 ka, 15 ka, 10 ka and 5 ka, including grounding line position and ice sheet thickness changes, along with a clear assessment of levels of confidence. The reconstruction shows that the Antarctic Ice sheet did not everywhere reach the continental shelf edge at its maximum, that initial retreat was asynchronous, and that the spatial pattern of deglaciation was highly variable, particularly on the inner shelf. The deglacial reconstruction is consistent with a moderate overall excess ice volume and with a relatively small Antarctic contribution to meltwater pulse la. We discuss key areas of uncertainty both around the continent and by time interval, and we highlight potential priorities for future work. The synthesis is intended to be a resource for the modelling and glacial geological community

1 September 2014 in Quaternary Science Reviews
Verified
Journal Article
Open access
DHDominic A. Hodgson
Dominic A. Hodgson
AGAlastair G.C. Graham
Alastair G.C. Graham
SRStephen Roberts
Stephen Roberts
MBMichael J. Bentley
Michael J. Bentley
CCColm Ó Cofaigh
Colm Ó Cofaigh
JSJames A. Smith
James A. Smith
This paper is the maritime and sub Antarctic contribution to the Scientific Committee for Antarctic Research (SCAR) Past Antarctic Ice Sheet Dynamics (PAIS) community Antarctic Ice Sheet reconstruction. The overarching aim for all sectors of Antarctica was to reconstruct the Last Glacial Maximum (LGM) ice sheet extent and thickness, and map the subsequent deglaciation in a series of 5000 year time slices. However, our review of the literature found surprisingly few high quality chronological constraints on changing glacier extents on these timescales in the maritime and sub Antarctic sector. Therefore, in this paper we focus on an assessment of the terrestrial and offshore evidence for the LGM ice extent, establishing minimum ages for the onset of deglaciation, and separating evidence of deglaciation from LGM limits from those associated with later Holocene glacier fluctuations. Evidence included geomorphological descriptions of glacial landscapes, radiocarbon dated basal peat and lake sediment deposits, cosmogenic isotope ages of glacial features and molecular biological data. We propose a classification of the glacial history of the maritime and sub Antarctic islands based on this assembled evidence. These include: (Type I) islands which accumulated little or no LGM ice; (Type II) islands with a limited LGM ice extent but evidence of extensive earlier continental shelf glaciations; (Type III) seamounts and volcanoes unlikely to have accumulated significant LGM ice cover; (Type IV) islands on shallow shelves with both terrestrial and submarine evidence of LGM (and/or earlier) ice expansion; (Type V) Islands north of the Antarctic Polar Front with terrestrial evidence of LGM ice expansion; and (Type VI) islands with no data. Finally, we review the climatological and geomorphological settings that separate the glaciological history of the islands within this classification scheme

1 August 2020 in Science of The Total Environment
Verified
Journal Article
Closed access
HWHaoxian Wang
Haoxian Wang
XLXuming Li
Xuming Li
YCYang Chen
Yang Chen
ZLZibo Li
Zibo Li
DHDavid William Hedding
David William Hedding
JCJun Chen
Jun Chen

1 September 2020 in Science of The Total Environment
Verified
Journal Article
Closed access
WWWeihua Wu
Weihua Wu
SQShuyi Qu
Shuyi Qu
WNWerner Nel
Werner Nel
JJJunfeng Ji
Junfeng Ji

5 September 2002 in Earth Surface Processes and Landforms
Verified
Journal Article
Closed access
PDF file
PSPaul Sumner
Paul Sumner
WNWerner Nel
Werner Nel