Abrupt transitions of regional climate in response to the gradual rise in atmospheric greenhouse gas concentrations are notoriously difficult to foresee. However, such events could be particularly challenging in view of the capacity required for society and ecosystems to adapt to them. We present, to our knowledge, the first systematic screening of the massive climate model ensemble informing the recent Intergovernmental Panel on Climate Change report, and reveal evidence of 37 forced regional abrupt changes in the ocean, sea ice, snow cover, permafrost, and terrestrial biosphere that arise after a certain global temperature increase. Eighteen out of 37 events occur for global warming levels of less than 2°, a threshold sometimes presented as a safe limit. Although most models predict one or more such events, any specific occurrence typically appears in only a few models. We find no compelling evidence for a general relation between the overall number of abrupt shifts and the level of global warming. However, we do note that abrupt changes in ocean circulation occur more often for moderate warming (less than 2°), whereas over land they occur more often for warming larger than 2°. Using a basic proportion test, however, we find that the number of abrupt shifts identified in Representative Concentration Pathway (RCP) 8.5 scenarios is significantly larger than in other scenarios of lower radiative forcing. This suggests the potential for a gradual trend of destabilization of the climate with respect to such shifts, due to increasing global mean temperature change.abrupt climate change | critical transitions | CMIP5 | IPCC | climate change

Coronavirus, uses the Angiotensin Converting Enzyme-2 Receptor to enter airway cells. Viral endocytosis is mediated by several factors, including clathrin, the adaptor protein-2 complex (AP2) and the adaptor-associated kinase-1 (AAK1). 2 According to a recent report, 3 COVID-19, the disease caused by SARS-CoV-2, is characterized by three clinical patterns: no symptoms, mild to moderate disease, severe pneumonia requiring admission to Intensive Care Unit (ICU) in up to 31% of the patients. 3 Thus far, there is no specific therapy for COVID-19 infection. No benefit of lopinavir-ritonavir treatment resulted in a recent trial. 4 Hydroxychloroquine, currently used in view of its "in vitro" observed effect of reduction of viral replication, seems unsatisfactory. 5 Elevated proinflammatory cytokine/chemokine responses seem associated with respiratory failure. 3 Recently, tocilizumab, an interleukin-6 inhibitor, was reported as effective in patients with severe COVID-19 pneumonia. 6 Baricitinib, another inhibitor of cytokine-release, seems an interesting anti-inflammatory drug. It is a Janus kinase inhibitor (anti-JAK) licensed for the treatment of rheumatoid arthritis (RA) with good efficacy and safety records. 7 Moreover it seems to have anti-viral effects by its affinity for AP2-associated protein AAK1, reducing SARS-CoV-2 endocytosis. 8 On this basis, we assessed the safety of baricitinib therapy combined with lopinavir-ritonavir in moderate COVID-19 pneumonia patients and we evaluated its clinical impact.All consecutive hospitalized patients (March 16th −30th) with moderate COVID-19 pneumonia, older than 18 years, were treated for 2 weeks with baricitinib tablets 4 mg/day added to ritonavir-lopinavir therapy. The last consecutive patients with moderate COVID-19 pneumonia receiving standard of care therapy (lopinavir/ritonavir tablets 250 mg/bid and hydroxychloroquine 400 mg/day/orally for 2 weeks) admitted before the date of the first baricitinib-treated patient served as controls. Antibiotics were scheduled only in the case of suspected bacterial infection.Inclusion criteria were: a. SARS-Co-V2 positivity in the nasal/oral swabs; b. presence of at least 3 of the following symptoms: fever, cough, myalgia, fatigue; c. evidence of radiological pneumonia . After discharge, patients treated with baricitinib were planned to be followed for additional 6 weeks. Exclusion criteria: history of thrombophlebitis (TP), latent tuberculosis infection (QuantiFERON Plus-test positivity, Qiagen, Germany 9 ), pregnancy and lactation.Mild to moderate COVID-19 disease definition: presence of bilateral pneumonia with or without ground glass opacity and in absence of consolidation, not requiring intubation at enrollment; arterial oxygen saturation (SpO2) > 92% at room-air, and ratio arterial oxygen partial pressure/fractional inspired oxygen (PaO2/FiO2) 10 0-30 0 mmHg. Parameters daily accessed were: fever, pulmonary function, Modified Early Warning Score (MEWS), 10 pulse rate, blood pressure. After the initial execution, r...

Observations over the 20th century evidence no long-term warming in the subpolar North Atlantic (SPG). This region even experienced a rapid cooling around 1970, raising a debate over its potential reoccurrence. Here we assess the risk of future abrupt SPG cooling in 40 climate models from the fifth Coupled Model Intercomparison Project (CMIP5). Contrary to the long-term SPG warming trend evidenced by most of the models, 17.5% of the models (7/40) project a rapid SPG cooling, consistent with a collapse of the local deep-ocean convection. Uncertainty in projections is associated with the models’ varying capability in simulating the present-day SPG stratification, whose realistic reproduction appears a necessary condition for the onset of a convection collapse. This event occurs in 45.5% of the 11 models best able to simulate the observed SPG stratification. Thus, due to systematic model biases, the CMIP5 ensemble as a whole underestimates the chance of future abrupt SPG cooling, entailing crucial implications for observation and adaptation policy.