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People experience the consequences of a rapidly changing Arctic as the combined effects of physical conditions; responses of biological resources; impacts on infrastructure; decisions influencing adaptive capacities; and both environmental and international influences on economics and well-being. Living and innovating in Arctic environments over millennia, Indigenous Peoples have evolved holistic knowledge providing resilience and sustainability. Indigenous expertise is augmented by scientific abilities to reconstruct past environments and to model and predict future changes. Applying the combined understanding of Indigenous and scientific experts will be important if decision makers (from communities to governments) are to help mitigate and adapt to a rapidly changing Arctic. Considerable discussion among diverse collaborators suggests that addressing unprecedented Arctic environmental changes requires hearing one another, aligning values, and collaborating across knowledge systems, disciplines, and sectors of society. 

The Askaryan Radio Array (ARA) is an ultrahigh energy (UHE, >10^17  eV) neutrino detector designed to observe neutrinos by searching for the radio waves emitted by the relativistic products of neutrino-nucleon interactions in Antarctic ice. In this paper, we present constraints on the diffuse flux of ultrahigh energy neutrinos between 1016 and 1021  eV resulting from a search for neutrinos in two complementary analyses, both analyzing four years of data (2013–2016) from the two deep stations (A2, A3) operating at that time. We place a 90% CL upper limit on the diffuse all flavor neutrino flux at 1018  eV of EF(E)=5.6×10^−16  cm^−2 s^−1 sr^−1. This analysis includes four times the exposure of the previous ARA result and represents approximately 1/5^th the exposure expected from operating ARA until the end of 2022.