| Summary: | Stable isotope ratios of oxygen (δ18Op) and hydrogen (δDp) record information about the hydrological cycle. These signals are preserved in natural archives, such as speleothems, stalagmites, ice cores, and pedogenic carbonates. Recent studies have used these proxy records of water isotopologues to reconstruct the evolution of paleoclimates, paleoenvironments, and even tectonic-related changes in surface elevations. However, such reconstructions require information about the atmospheric dynamics that drive the spatial variability of isotopic ratios. δ18Op and δDp are known to reflect the history of air masses, surface temperature, precipitation, and synoptic-scale atmospheric teleconnection patterns like the North Atlantic Oscillation (NAO). Climate-driven variations in these data can complicate their interpretation of geologic processes. The NAO is the predominant mode of inter-annual and seasonal variability that controls the weather and climate system across the North Atlantic region and continental Europe. The influence of the NAO on the Global Network of Isotopes in Precipitation (GNIP) stations records of δ18Op and δDp across Europe was previously studied in the winter season when the NAO impacts are well defined. Here we build upon previous work by (1) investigating the present-day NAO-δ18Op and -δDp relationships and their associated atmospheric dynamics and causal mechanism in all seasons, and (2) studying the NAO’s influence on the δ18O and δD in precipitation in the late Cenozoic. We focus on the latter since many δ18Op- and δDp-based studies tackle problems in the Late Cenozoic. In addition, important characteristics of such pressure systems (e.g., the location of the centers of maximum and minimum pressures and axis of polarity) may change over longer (centennial to geological) time scales in response to different forcings such as atmospheric CO2, paleogeography, orbital changes, and land-surface cover. To achieve the study’s first goal, we explore the NAO-δ18Op and -δDp link by tracking the NAO in ...
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