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  1. null (Ed.)
    Prior to 2004, geological sampling in the Arctic Ocean was mainly restricted to near-surface Quaternary sediments. Thus, the long-term pre-Quaternary geological history is still poorly known. With the successful completion of the Arctic Coring Expedition (ACEX) (Integrated Ocean Drilling Program Expedition 302) in 2004, a new era in Arctic research began. Employing a novel multivessel approach, the first mission-specific platform (MSP) expedition of the Integrated Ocean Drilling Program proved that drilling in permanently ice-covered regions is possible. During ACEX, 428 m of Quaternary, Neogene, Paleogene, and Campanian sediment on Lomonosov Ridge were penetrated, providing new and unique insights into Cenozoic Arctic paleoceanographic and climate history. Although it was highly successful, ACEX also had three important limitations. The ACEX sequence contains either a large hiatus spanning the time interval from late Eocene to middle Miocene (based on the original biostratigraphic age model) or an interval of strongly reduced sedimentation rates (based on a more recent Os-Re-isotope-based age model). This is a critical time interval, spanning the time when prominent changes in global climate took place during the transition from the early Cenozoic Greenhouse Earth to the late Cenozoic Icehouse Earth. Furthermore, generally poor recovery during ACEX prevented detailed and continuous reconstruction of Cenozoic climate history. Finally, a higher-resolution reconstruction of Arctic rapid climate change during Neogene and Pleistocene times could not be achieved during ACEX. Therefore, Expedition 377 (Arctic Ocean Paleoceanography [ArcOP]) will return to the Lomonosov Ridge for a second MSP-type drilling campaign with the International Ocean Discovery Program to fill these major gaps in our knowledge on Arctic Ocean paleoenvironmental history through Cenozoic times and its relationship to global climate history. The overall goal of this drilling campaign is to recover a complete stratigraphic sedimentary record of the southern Lomonosov Ridge to meet our highest priority paleoceanographic objective, the continuous long-term Cenozoic climate history of the central Arctic Ocean. Furthermore, sedimentation rates two to four times higher than those of ACEX permit higher-resolution studies of Arctic climate change. The expedition goal can be achieved through careful site selection, the use of appropriate drilling technology and ice management, and by applying multiproxy approaches to paleoceanographic, paleoclimatic, and age-model reconstructions. The expedition will complete one primary deep drill hole (proposed Site LR-11B) to 900 meters below seafloor (mbsf), supplemented by a short drill site (LR-10B) to 50 mbsf, to recover an undisturbed uppermost (Quaternary) sedimentary section. This plan should ensure complete recovery so scientists can construct a composite section that spans the full age range through the Cenozoic. 
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  2. Hannula, K. (Ed.)
    Active learning research emerged from the undergraduate STEM education communities of practice, some of whom identify as discipline-based education researchers (DBER). Consequently, current frameworks of active learning are largely inductive and based on emergent patterns observed in undergraduate teaching and learning. Alternatively, classic learning theories historically originate from the educational psychology community, which often takes a theory-driven, or deductive research approach. The broader transdisciplinary education research community is now struggling to reconcile the two. That is, how is a theory of active learning distinct from other theories of knowledge construction? We discuss the underpinnings of active learning in the geosciences, drawing upon extant literature from the educational psychology community on engagement. Based on Sinatra et al. engagement framework, we propose a model for active learning in the geosciences with four dimensions: behavioral, emotional, cognitive, and agentic. We then connect existing literature from the geoscience education community to the model to demonstrate the current gaps in our literature base and opportunities to move the active learning geoscience education research (GER) forward. We propose the following recommendations for future investigation of active learning in the geosciences: (1) connect future GER to our model of active learning in the geosciences, (2) measure more than content learning, (3) document research methods and outcomes with effect sizes to accumulate evidence, and (4) prioritize research on dimensions of active learning essential to the geosciences. 
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