Secretion of severe acute respiratory syndrome coronavirus 2 in urine

PURPOSE OF REVIEW: Despite the plethora of publications discussing the severe respiratory coronavirus 2 (SARS-CoV-2), evidence of viral secretion in urine is sparse. RECENT FINDINGS: We could identify 34 publications including a total of 2172 patients. Among those, 549 patients were tested for SARS-CoV-2 secretion in urine, which was detected in only 38 patients (6.9%). Within the seven studies displaying positive results, the majority of positive patients (86.8%) was from not yet peer-reviewed studies including weak data and heterogeneous techniques for sample testing. Furthermore, none of the studies available in the literature addressed the virulence of detected viral RNA in urine. SUMMARY: Overall, only seven studies were able to detect SARS-CoV-2 secretion in urine, all of them with a considerably low rate of positivity. However, these studies were of rather low quality considering their methodology. Despite this, as SARS-CoV-2 has been detected in urine, it is of importance to discuss safety and urinary hygiene protocols. Until further research provides valid data on viral shedding and virulence in urine, potential risk of transmission through urine cannot be ruled out. Therefore, safety and hygiene measures need to be discussed

Multidecadal signal of solar variability in the upper troposphere during the 20th century

Studies based on data from the past 25–45 years show that irradiance changes related to the 11-yr solar cycle affect the circulation of the upper troposphere in the subtropics and midlatitudes. The signal has been interpreted as a northward displacement of the subtropical jet and the Ferrel cell with increasing solar irradiance. In model studies on the 11-yr solar signal this could be related to a weakening and at the same time broadening of the Hadley circulation initiated by stratospheric ozone anomalies. Other studies, focusing on the direct thermal effect at the Earth’s surface on multidecadal scales, suggest a strengthening of the Hadley circulation induced by an increased equator-to-pole temperature gradient. In this paper we analyse the solar signal in the upper troposphere since 1922, using statistical reconstructions based on historical upper-air data. This allows us to address the multidecadal variability of solar irradiance, which was supposedly large in the first part of the 20th century. Using a simple regression model we find a consistent signal on the 11-yr time scale which fits well with studies based on later data. We also find a significant multidecadal signal that is similar to the 11-yr signal, but somewhat stronger. We interpret this signal as a poleward shift of the subtropical jet and the Ferrel cell. Comparing the magnitude of the two signals could provide important information on the feedback mechanisms involved in the solar climate relationship with respect to the Hadley and Ferrel circulations. However, in view of the uncertainty in the solar irradiance reconstructions, such interpretations are not currently possible

Prediction from Weeks to Decades

This white paper is a synthesis of several recent workshops, reports and published literature on monthly to decadal climate prediction. The intent is to document: (i) the scientific basis for prediction from weeks to decades; (ii) current capabilities; and (iii) outstanding challenges. In terms of the scientific basis we described the various sources of predictability, e.g., the Madden Jullian Ocillation (MJO); Sudden Stratospheric Warmings; Annular Modes; El Niño and the Southern Oscillation (ENSO); Indian Ocean Dipole (IOD); Atlantic “Niño;” Atlantic gradient pattern; snow cover anomalies, soil moisture anomalies; sea-ice anomalies; Pacific Decadal Variability (PDV); Atlantic Multi-Decadal Variability (AMV); trend among others. Some of the outstanding challenges include how to evaluate and validate prediction systems, how to improve models and prediction systems (e.g., observations, data assimilation systems, ensemble strategies), the development of seamless prediction systems