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2.
Nat Commun ; 13(1): 7866, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36543772

RESUMO

The variability of the northern westerlies has been considered as one of the key elements for modern and past climate evolution. Their multiscale behavior and underlying control mechanisms, however, are incompletely understood, owing to the complex dynamics of Atlantic sea-level pressures. Here, we present a multi-annually resolved record of the westerly drift over the past 6,500 years from northern Italy. In combination with more than 20 other westerly-sensitive records, our results depict the non-stationary westerly-affected regions over mainland Europe on multi-decadal to multi-centennial time scales, showing that the direction of the westerlies has changed with respect to the migrations of the North Atlantic centers of action since the middle Holocene. Our findings suggest the crucial role of the migrations of the North Atlantic dipole in modulating the westerly-affected domain over Europe, possibly modulated by Atlantic Ocean variability.


Assuntos
Clima , Vento , Europa (Continente) , Oceano Atlântico , Itália
4.
Nat Commun ; 13(1): 4898, 2022 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-35987980

RESUMO

The Little Ice Age (LIA; ca. 1450-1850 C.E.) is the best documented cold period of the past millennium, characterized by high-frequency volcanism, low solar activity, and high variability of Arctic sea-ice cover. Past studies of LIA Atlantic circulation changes have referenced the North Atlantic Oscillation (NAO), but recent studies have noted that LIA climate patterns appear to possess complexity not captured by an NAO analogue. Here, we present a new precipitation-sensitive stalagmite record from northern Italy that covers the past 800 years. We show that in the early LIA (1470-1610 C.E.), increased atmospheric ridging over northern Europe split the climatological westerlies away from central and northern Europe, possibly caused by concurrent Artic sea-ice reduction. With ongoing ice melting in the northern high latitudes and decreasing solar irradiance in the coming years, the early LIA may potentially serve as an analogue for European hydroclimatic conditions in the coming decades.


Assuntos
Clima , Camada de Gelo , Regiões Árticas , Mudança Climática , Europa (Continente)
5.
Sci Rep ; 7(1): 10074, 2017 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-28855634

RESUMO

The first "Out of Africa" migrations represent a seminal event in the history of humankind. At the gates of Europe, the first appearance of Hominins is recorded in Georgia, 1.8 million years ago (Ma); however, the picture of migration across the continent remains incomplete. Vallonnet Cave (France) is a Lower Paleolithic prehistoric site with traces of hominin activities including lithic remains and cut-marks on mammal bones. Here, we apply the uranium-lead (U-Pb) methods to two flowstones to date the intervening archaeological levels. The U-Pb data, coupled with paleomagnetic constraints, provide an age range from 1.2 to 1.1 Ma. The results conclusively demonstrate that Vallonnet Cave is one of the oldest European prehistoric sites in France with early hominin occupations associated with an Epivillafranchian fauna. Combined with data from other archaeological sites, the new precise chronology suggests a widespread occupation the Northern Mediterranean to Southwestern Europe at ~1.2 Ma.


Assuntos
Osso e Ossos/anatomia & histologia , Fósseis/anatomia & histologia , Hominidae/anatomia & histologia , Migração Humana/história , Datação Radiométrica/métodos , África , Animais , Arqueologia/métodos , Cavernas , Fósseis/história , França , Sedimentos Geológicos/análise , República da Geórgia , História Antiga , Humanos , Chumbo/química , Mamíferos/anatomia & histologia , Urânio/química
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