TY  - JOUR
A1  - Maslin, Mark A.
A1  - Brierley, Chris M.
A1  - Milner, Alice M.
A1  - Shultz, Susanne
A1  - Trauth, Martin H.
A1  - Wilson, Katy E.
T1  - East African climate pulses and early human evolution
JF  - Quaternary science reviews : the international multidisciplinary research and review journal
N2  - Current evidence suggests that all of the major events in hominin evolution have occurred in East Africa. Over the last two decades, there has been intensive work undertaken to understand African palaeoclimate and tectonics in order to put together a coherent picture of how the environment of East Africa has varied in the past. The landscape of East Africa has altered dramatically over the last 10 million years. It has changed from a relatively flat, homogenous region covered with mixed tropical forest, to a varied and heterogeneous environment, with mountains over 4 km high and vegetation ranging from desert to cloud forest. The progressive rifting of East Africa has also generated numerous lake basins, which are highly sensitive to changes in the local precipitation-evaporation regime. There is now evidence that the presence of precession-driven, ephemeral deep-water lakes in East Africa were concurrent with major events in hominin evolution. It seems the unusual geology and climate of East Africa created periods of highly variable local climate, which, it has been suggested could have driven hominin speciation, encephalisation and dispersal out of Africa. One example is the significant hominin speciation and brain expansion event at -1.8 Ma that seems to have been coeval with the occurrence of highly variable, extensive, deep-water lakes. This complex, climatically very variable setting inspired first the variability selection hypothesis, which was then the basis for the pulsed climate variability hypothesis. The newer of the two suggests that the long-term drying trend in East Africa was punctuated by episodes of short, alternating periods of extreme humidity and aridity. Both hypotheses, together with other key theories of climate-evolution linkages, are discussed in this paper. Though useful the actual evolution mechanisms, which led to early hominins are still unclear and continue to be debated. However, it is clear that an understanding of East African lakes and their palaeoclimate history is required to understand the context within which humans evolved and eventually left East Africa. (C) 2014 The Authors. Published by Elsevier Ltd.
KW  - Human evolution
KW  - East Africa
KW  - Palaeoclimatology
KW  - Palaeoliminology
KW  - Tectonics
KW  - Hominin
KW  - Orbital forcing
KW  - Cenozoic climate transitions
KW  - Pulsed climate variability hypothesis
Y1  - 2014
U6  - https://doi.org/10.1016/j.quascirev.2014.06.012
SN  - 0277-3791
VL  - 101
SP  - 1
EP  - 17
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Comas-Bru, Laia
A1  - Harrison, Sandy P.
A1  - Werner, Martin
A1  - Rehfeld, Kira
A1  - Scroxton, Nick
A1  - Veiga-Pires, Cristina
A1  - Ahmad, Syed Masood
A1  - Brahim, Yassine Ait
A1  - Mozhdehi, Sahar Amirnezhad
A1  - Arienzo, Monica
A1  - Atsawawaranunt, Kamolphat
A1  - Baker, Andy
A1  - Braun, Kerstin
A1  - Breitenbach, Sebastian Franz Martin
A1  - Burstyn, Yuval
A1  - Chawchai, Sakonvan
A1  - Columbu, Andrea
A1  - Deininger, Michael
A1  - Demeny, Attila
A1  - Dixon, Bronwyn
A1  - Hatvani, Istvan Gabor
A1  - Hu, Jun
A1  - Kaushal, Nikita
A1  - Kern, Zoltan
A1  - Labuhn, Inga
A1  - Lachniet, Matthew S.
A1  - Lechleitner, Franziska A.
A1  - Lorrey, Andrew
A1  - Markowska, Monika
A1  - Nehme, Carole
A1  - Novello, Valdir F.
A1  - Oster, Jessica
A1  - Perez-Mejias, Carlos
A1  - Pickering, Robyn
A1  - Sekhon, Natasha
A1  - Wang, Xianfeng
A1  - Warken, Sophie
A1  - Atkinson, Tim
A1  - Ayalon, Avner
A1  - Baldini, James
A1  - Bar-Matthews, Miryam
A1  - Bernal, Juan Pablo
A1  - Boch, Ronny
A1  - Borsato, Andrea
A1  - Boyd, Meighan
A1  - Brierley, Chris
A1  - Cai, Yanjun
A1  - Carolin, Stacy
A1  - Cheng, Hai
A1  - Constantin, Silviu
A1  - Couchoud, Isabelle
A1  - Cruz, Francisco
A1  - Denniston, Rhawn
A1  - Dragusin, Virgil
A1  - Duan, Wuhui
A1  - Ersek, Vasile
A1  - Finne, Martin
A1  - Fleitmann, Dominik
A1  - Fohlmeister, Jens Bernd
A1  - Frappier, Amy
A1  - Genty, Dominique
A1  - Holzkamper, Steffen
A1  - Hopley, Philip
A1  - Johnston, Vanessa
A1  - Kathayat, Gayatri
A1  - Keenan-Jones, Duncan
A1  - Koltai, Gabriella
A1  - Li, Ting-Yong
A1  - Lone, Mahjoor Ahmad
A1  - Luetscher, Marc
A1  - Mattey, Dave
A1  - Moreno, Ana
A1  - Moseley, Gina
A1  - Psomiadis, David
A1  - Ruan, Jiaoyang
A1  - Scholz, Denis
A1  - Sha, Lijuan
A1  - Smith, Andrew Christopher
A1  - Strikis, Nicolas
A1  - Treble, Pauline
A1  - Unal-Imer, Ezgi
A1  - Vaks, Anton
A1  - Vansteenberge, Stef
A1  - Voarintsoa, Ny Riavo G.
A1  - Wong, Corinne
A1  - Wortham, Barbara
A1  - Wurtzel, Jennifer
A1  - Zhang, Haiwei
T1  - Evaluating model outputs using integrated global speleothem records of climate change since the last glacial
JF  - Climate of the past : an interactive open access journal of the European Geosciences Union
N2  - Although quantitative isotope data from speleothems has been used to evaluate isotope-enabled model simulations, currently no consensus exists regarding the most appropriate methodology through which to achieve this. A number of modelling groups will be running isotope-enabled palaeoclimate simulations in the framework of the Coupled Model Intercomparison Project Phase 6, so it is timely to evaluate different approaches to using the speleothem data for data–model comparisons. Here, we illustrate this using 456 globally distributed speleothem δ18O records from an updated version of the Speleothem Isotopes Synthesis and Analysis (SISAL) database and palaeoclimate simulations generated using the ECHAM5-wiso isotope-enabled atmospheric circulation model. We show that the SISAL records reproduce the first-order spatial patterns of isotopic variability in the modern day, strongly supporting the application of this dataset for evaluating model-derived isotope variability into the past. However, the discontinuous nature of many speleothem records complicates the process of procuring large numbers of records if data–model comparisons are made using the traditional approach of comparing anomalies between a control period and a given palaeoclimate experiment. To circumvent this issue, we illustrate techniques through which the absolute isotope values during any time period could be used for model evaluation. Specifically, we show that speleothem isotope records allow an assessment of a model's ability to simulate spatial isotopic trends. Our analyses provide a protocol for using speleothem isotope data for model evaluation, including screening the observations to take into account the impact of speleothem mineralogy on δ18O values, the optimum period for the modern observational baseline and the selection of an appropriate time window for creating means of the isotope data for palaeo-time-slices.
Y1  - 2019
U6  - https://doi.org/10.5194/cp-15-1557-2019
SN  - 1814-9324
SN  - 1814-9332
VL  - 15
IS  - 4
SP  - 1557
EP  - 1579
PB  - Copernicus
CY  - Göttingen
ER  -