The Last Glacial Maximum (LGM) ice extent in the western Danish North Sea remains unchartered, which impedes our understanding of the last glacial to Holocene transition in the region. Despite increasing interest in the shallow subsurface of the North Sea, there is still a knowledge gap concerning this transition. In this study, we describe the geological evolution of the southern part of the western Danish North Sea using high‐resolution seismic data, with emphasis on the LGM and the late Quaternary development. We have identified a large glaciotectonic complex that delineates the maximum extent of the LGM ice sheet and indicates a general NNW‐SSE ice flow direction. We describe the drainage history associated with a large ice‐dammed lake, which covered most of the southern North Sea, presumably lasting for more than 2000 years from the LGM until ~19 cal kyrs BP. Based on the interpreted seismic profiles and regional depositional and deformational patterns, we provide a model for how the deglaciation unfolded in the western Danish North Sea. The deglacial sequence of events is placed into a late Quaternary context and related to the existing stratigraphic models for the area. Our study sheds new light on the distribution of potentially challenging buried landscapes for offshore construction and windfarm development.
ABSTRACT The expansion of the Linearbandkeramik (LBK; ca. 5400–4950 BCE) represents one of the most significant episodes of prehistoric population movement during the Neolithisation of Europe. Although migration is widely accepted as the principal mechanism of this expansion, the roles of ecological adaptation, population pressure and environmental constraints remain debated. We investigate diachronic changes in LBK settlement suitability using the human existence potential (HEP) approach, a species distribution modelling framework, applied to archaeological settlement data from the earliest (eLBK) and full LBK. HEP models were generated using two independent palaeoclimatic reconstructions (PaleoClim and CHELSA) combined with a soil quality index (SQI). Across all model variants, the environmental structure associated with persistent LBK settlement remained remarkably stable through time. Although the environmental envelope and geographical distribution expanded, many landscapes incorporated during later phases already exhibited high suitability in the eLBK models. The results provide little support for repeated large‐scale ecological adaptation or for population pressure and limits of carrying capacity as primary drivers of dispersal. Instead, they indicate considerable environmental flexibility from the outset and suggest that environmental suitability structured, but did not determine, the expansion of the LBK.
ABSTRACT Mesoamerican seasonally dry tropical forests (SDTFs) are floristically differentiated, spatially discontinuous and affected by Quaternary climatic change; yet, effects on long‐term suitability, refugial persistence and environmental connectivity remain unresolved. We assessed whether climatic oscillations over the last 800 ka altered the extent and connectivity of suitable SDTF areas more strongly than core position (areas of high climatic suitability). Climatic suitability was modelled for 103 woody plant species from 25 families and projected at 1‐ka intervals. Palaeoclimatic suitability dynamics, candidate refugia and connectivity were evaluated using continuous and binary multispecies consensus models. Maximum binary overlap remained high (89–94 models) across 22 representative palaeoclimatic time slices, while the main high‐suitability core persisted along the Pacific slope of western and southern Mexico. The Yucatán Peninsula and northern Central America showed temporal variation in suitability and continuity. Seven candidate refugial nuclei were identified, six forming a discontinuous Pacific chain and one in north‐eastern Yucatán. Connectivity analyses identified five sectors of potential environmental connectivity, the largest spanning the Balsas Basin–southern Mexico. No connection was detected between the Pacific and Gulf slopes, and northern Central America remained disconnected from Mexico. Quaternary climatic oscillations reconfigured the extent and spatial continuity of suitable environments while preserving persistent high‐suitability cores.
ABSTRACT The hypothesis that temperate tree taxa survived the Last Glacial Maximum (LGM; 26.5–19 ka cal BP) in cryptic northern refugia has significant implications for European biogeography and postglacial vegetation history. Recently, sedimentary ancient DNA recovered from offshore sediment cores in the Southern River System of the North Sea Basin has been interpreted as evidence for the local persistence of temperate woodland taxa during the LGM. This review critically evaluates that hypothesis by synthesising the currently available palaeobotanical and sedimentary ancient DNA evidence from the North Sea Basin and adjacent terrestrial regions. Independent palaeoclimate reconstructions consistently indicate cold, dry conditions, continuous permafrost and temperatures well below the ecological requirements of temperate woodland trees. These reconstructions are broadly congruent with pollen, plant macrofossil, vertebrate and coleopteran records, which collectively indicate the persistence of low‐productivity arctic to subarctic steppe–tundra vegetation throughout the region during the LGM. This strong convergence among independent palaeoenvironmental datasets contrasts with limited support for the local persistence of temperate woodland communities throughout the LGM in the North Sea Basin.
ABSTRACT Understanding Earth‐surface processes along the fringes of large ice sheets is integral to deciphering cold‐region environmental variability and anticipating slope instability under climate change. We investigate the Meseta Chile Chico, a volcanic plateau in the central Patagonian Andes, located at the eastern margin of the former Patagonian Ice Sheet. Here, glacier retreat patterns are well‐constrained, while the influence of periglacial, paraglacial, and postglacial processes is not. We employ geomorphological mapping integrated with geological and palaeoclimate reconstructions to provide a spatio‐temporal model of landscape evolution. Enhanced erosion since the late Pliocene, caused by differential tectonic uplift and glacial isostatic rebound, produced the rugged morphology that characterizes the Meseta Chile Chico. During the Last Glacial Maximum, glaciers occupied surrounding valleys, while the surface of the plateau was reshaped by long‐lasting periglacial freeze‐thaw cycles and nivation. Postglacial landscape adjustment included intensified landslide activity along the edges of the plateau (linked to paraglacial de‐buttressing at its bordering valleys) and regional base‐level changes. During the Holocene, flow‐type landslides became increasingly controlled by climatic variability. The geomorphology of the Meseta Chile Chico reflects an interplay between inherited geology, (de)glaciation, and climate, highlighting the importance of an interdisciplinary approach for understanding recent landscape dynamics in deglaciating mountain regions.
