Download
Cite as:
Lemma, B.; Seifu Kebede, G.; Nemomissa, S.; Otte, I.; Glaser, B. &amp; Zech, M. (2020): <b>Spatial and temporal 2H and 18O isotope variation of contemporary precipitation in the Bale Mountains, Ethiopia</b>. <i>Isotopes in Environmental and Health Studies</i> <b>56</b>(1), 1-14.

Resource Description
Title: Spatial and temporal 2H and 18O isotope variation of contemporary precipitation in the Bale Mountains, Ethiopia
FOR816dw ID: 135
Publication Date: 2020-02-03
License and Usage Rights:
Resource Owner(s):
Individual: Bruk Lemma
Contact:
Individual: Gurmessa Seifu Kebede
Contact:
Individual: Sileshi Nemomissa
Contact:
Individual: Insa Otte
Contact:
Individual: Bruno Glaser
Contact:
Individual: Michael Zech
Contact:
Abstract:
East Africa is an underrepresented region in respect of monitoring<br/> the stable isotopic composition of precipitation (δ18Oprec and<br/> δ2Hprec). In 2017, we collected precipitation samples from ten<br/> weather stations located along an altitudinal transect ranging<br/> from 1304 to 4375 m a.s.l. The δ18Oprec and δ2Hprec values varied<br/> from –8.7 to +3.7‰ and –38 to +29‰, respectively. The local<br/> meteoric water line is characterised by a lower slope, a higher<br/> intercept and more positive d-excess values (δ2H = 5.3 ± 0.2<br/> * δ18O + 14.9 ± 0.9) compared to the global meteoric water line.<br/> Both altitude and amount of precipitation clearly correlate with<br/> our isotope data. However, the δ18Oprec and δ2Hprec values show<br/> at the same time a seasonal pattern reflecting rainy versus dry<br/> season. More enriched isotope values prevailed shortly after the<br/> end of the dry season; more depleted isotope values coincided<br/> with high precipitation amounts recorded in May, August and<br/> September. Moreover, HYSPLIT trajectories reveal that during the<br/> dry season water vapour originates primarily from the Arabian<br/> Sea, whereas during the wet season it originates primarily from<br/> the Southern Indian Ocean. These findings challenge the<br/> traditional amount effect interpretation of paleoclimate isotope<br/> records from East Africa and rather point to a previously<br/> underestimated source effect.
Keywords:
| water | p5 | isoptopes | precipitation | geochemistry |
Literature type specific fields:
ARTICLE
Journal: Isotopes in Environmental and Health Studies
Volume: 56
Issue: 1
Page Range: 1-14
Metadata Provider:
Individual: Luise Wraase
Contact:
Online Distribution:
Download File: http://vhrz669.hrz.uni-marburg.de/bale/publications.do?citid=135


Quick search

  • Publications:
  • Datasets:

Keywords

Datasets / Publications
afroalpine vegetation archaeology biomarker ecology Erica Ericaceous vegetation fauna geochemistry glacial chronology High-altitude habitation isoptopes lake sediment Late Pleistocene p5 paleoclimatic paleovegetation pollen sediment Settlement history vegetation