RESUMEN
Enhanced warm, salty subarctic inflows drive high-latitude atlantification, which weakens oceanic stratification, amplifies heat fluxes, and reduces sea ice. In this work, we show that the atmospheric Arctic Dipole (AD) associated with anticyclonic winds over North America and cyclonic winds over Eurasia modulates inflows from the North Atlantic across the Nordic Seas. The alternating AD phases create a "switchgear mechanism." From 2007 to 2021, this switchgear mechanism weakened northward inflows and enhanced sea-ice export across Fram Strait and increased inflows throughout the Barents Sea. By favoring stronger Arctic Ocean circulation, transferring freshwater into the Amerasian Basin, boosting stratification, and lowering oceanic heat fluxes there after 2007, AD+ contributed to slowing sea-ice loss. A transition to an AD- phase may accelerate the Arctic sea-ice decline, which would further change the Arctic climate system.
RESUMEN
Dropped head syndrome is a rare disorder involving an inability to hold the head upright. It may be caused by a variety of neuromuscular disorders and occasionally by pathological vertebral fractures. A 79-year-old man presented to a chiropractor with a two-year history of gradual-onset chin-on-chest posture and increased thoracic kyphosis, which had failed to respond to physical therapy. The chiropractor ordered whole spine computed tomography which revealed extensive mixed lytic and sclerotic changes and multiple thoracic compression fractures suggestive of metastasis. The chiropractor promptly referred the patient to an oncologist, who performed a biopsy confirming prostate adenocarcinoma. The patient's health deteriorated, and he expired three weeks later. This case highlights that chiropractors should be aware that patients may present to their office with symptoms related to undiagnosed cancer, such as spinal deformity and dropped head syndrome. Chiropractors should order advanced imaging when patients have red flag signs or symptoms (e.g., older age, progressive symptoms despite care) and refer to an oncologist when clinical features or testing are suggestive of metastasis.
RESUMEN
Arctic sea-ice loss is a leading indicator of climate change and can be attributed, in large part, to atmospheric forcing. Here, we show that recent ice reductions, weakening of the halocline, and shoaling of the intermediate-depth Atlantic Water layer in the eastern Eurasian Basin have increased winter ventilation in the ocean interior, making this region structurally similar to that of the western Eurasian Basin. The associated enhanced release of oceanic heat has reduced winter sea-ice formation at a rate now comparable to losses from atmospheric thermodynamic forcing, thus explaining the recent reduction in sea-ice cover in the eastern Eurasian Basin. This encroaching "atlantification" of the Eurasian Basin represents an essential step toward a new Arctic climate state, with a substantially greater role for Atlantic inflows.
