Climate, Environmental Change, and Resources of the African Mountains from the Mediterranean to the Equator

Messerli, Bruno; Winiger, Matthias

doi:10.2307/3673683

Cited by 73 publications

(22 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, much of the lower-lying terrain (below 1000 m) remains semi-arid, given the rain shadow effects of mountains, the cool upwelling water off the Somali coast and frictionally induced subsidence of the Somali jet paralleling the coast. The complexity of regional mountain climate is also apparent in North Africa, where conditions along the Mediterranean differ drastically from those in the Atlas to the west (Messerli and Winiger, 1992). Cold Atlantic Ocean temperatures also suppress precipitation over the Sahel region.…”

Section: Climatementioning

confidence: 90%

“…Episodes of mountain glaciation herald entire ecosystem alterations at lower elevations, and understanding the Quaternary climate evolution of Africa was recognised to be important for ecology and evolutionary biology (Livingstone, 1975). Highland regions also play a disproportionately important role in water and ecological resources for Africa, and evidence of changes in these regions over the last 20 ka has instigated research about climatic impacts on human civilisation and natural resources (Messerli and Winiger, 1992). Tracing glacial changes over time in African mountains thus delimits important local-to-regional responses to global-scale climate forcings.…”

Section: Introductionmentioning

confidence: 99%

“…This paper falls in succession to a number of comprehensive reviews of Quaternary glaciation (Rosqvist, 1990;Kaser and Osmaston, 2002;Osmaston and Harrison, 2005), hydrology (Gasse, 2000), climate dynamics and variability (Nicholson, 1996), vegetation changes (Olago, 2001), late Quaternary climatic change (Livingstone, 1975;Kiage and Liu, 2006), mountain climate and environmental change (Messerli and Winiger, 1992) and equatorial glaciers of East Africa (Hastenrath, 1984;Mahaney, 1989Mahaney, , 1990. To complement and update these previous efforts, this work characterises spatial and temporal dimensions of glacial activity with regard to climate context; it both synthesises the regional patterns and documents chronological and geographical details for palaeoglacier-specific localities.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Quaternary glaciation in Africa: key chronologies and climatic implications

Mark

Osmaston

2008

J Quaternary Science

View full text Add to dashboard Cite

Multiple episodes of Quaternary glaciation are evidenced on >10 distinct mountain localities throughout Africa, with the best dated sites from Kilimanjaro and Mt Kenya in equatorial East Africa. A general paucity of radiogenic dates constrains the glacial chronology, and regional sequences have largely been based on correlations by relative weathering of features. Excellent glacial moraine preservation and other features of erosion put limits on the spatial extent of palaeoglaciers, and have facilitated advances in palaeo-equilibrium line altitude (ELA) analyses. All radiocarbon dates (n < 30) provide minimum ages of deglaciation, and are consistent with a widespread synchronous advance during the Last Glacial Maximum (LGM, 21 AE 2 ka). K-Ar dates on Kilimanjaro lava flows initially recognised up to three glaciations prior to the LGM. Over 100 cosmogenic radionuclide (CRN) 36 Cl exposure ages on glacial erratics and bedrock from Kilimanjaro and Mt Kenya date 16 landforms, confirming maximum glacial extent prior to Marine Isotope Stage (MIS) 10. No glacial geological features have been dated to MIS 6. While on Kilimanjaro the CRN ages confirm a clear LGM (MIS 2) maximum, Mt Kenya lacks definitive LGM moraines. Lateglacial advances or stillstands on both mountains are suggested by low-relief moraines dating to 14.6 AE 1.2 ka (two boulders) on Mt Kenya and 16.3 AE 1.9 ka and 15.8 AE 2.5 ka on Kilimanjaro. Multiple moraines upvalley have early Holocene ages ranging from 11.2 AE 0.8 to 8.6 AE 0.2 ka. Isolated and equivocal dates on both mountains also provide speculative evidence that the maximum extent since MIS 5e may have occurred close to 30 ka, similar to sites in South America. New palaeoclimatic understanding from lake and ocean proxies suggests hypotheses for the source of low-latitude climate changes causing the advances that can be tested with improved dates. A high degree of intra-regional variance in ELA is observed, with differences by aspect reflecting precipitation gradients. Future work should include more CRN dates, improved mapping and inverse climate-mass balance modelling.

show abstract

Section: Climatementioning

confidence: 90%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Quaternary glaciation in Africa: key chronologies and climatic implications

Mark

Osmaston

2008

J Quaternary Science

View full text Add to dashboard Cite

show abstract

“…Mikesell 1960;Ajbiloua et al 2006;Esteban et al 2010). Moreover, the Moroccan landscape is subject to land degradation, desertification and ecosystem degradation (Barbero et al 1990;Messerli and Winiger 1992;Puigdefábregas and Mendizabal 1998;Parish and Funnell 1999;Sobrino and Raissouni 2000;McGregor et al 2009). Morocco has a number of protected terrestrial areas that are divided under several designations; National Park (11), Biological Reserve (5), Nature Reserve (13), Reserve (4), Natural Park (2), Botanical Park (1) and Forest Sanctuary (1) (World Database of Protected Areas [WDPA] Consortium 2009 version).…”

Section: Study Areamentioning

confidence: 96%

Area prioritization and performance evaluation of the conservation area network for the Moroccan herpetofauna: a preliminary assessment

et al. 2010

View full text Add to dashboard Cite

show abstract

“…Areas closer to the equator will have a longer wet season that tends to be bimodal, caused by the annual movement of the Intertropical Convergence Zone (O'Hare et al, 2005). The rainfall distribution in the Simien Mountains shows two maxima around 1800 and 3600 m (Messerli and Winiger, 1992), but detailed rainfall information about the study area is still lacking. Glacier limits reached lower on western slopes in East Africa (On the Kilimanjaro, Mt.…”

Section: Study Areamentioning

confidence: 99%