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Observational studies suggest that part of the North Atlantic Oscillation (NAO) variability may be attributed to the spectral ultra-violet (UV) irradiance variations associated to the 11-year solar cycle. The observed maximum surface pressure response in the North Atlantic occurs 2–4 years after solar maximum, and some model studies have identified that atmosphere–ocean feedbacks explain the multi-year lag. Alternatively, medium-to-high energy electron (MEE) precipitation, which peaks in the declining phase of the solar cycle, has been suggested as a potential cause of this lag. We use a coupled (ocean–atmosphere) climate prediction model and a state-of-the-art MEE forcing to explore the respective roles of irradiance and MEE precipitation on the NAO variability. Three decadal ensemble experiments were conducted over solar cycle 23 in an idealized setting. We found a weak ensemble-mean positive NAO response to the irradiance. The simulated signal-to-noise ratio remained very small, indicating the predominance of internal NAO variability. The lack of multi-annual lag in the NAO response was likely due to lagged solar signals imprinted in temperatures below the oceanic mixed-layer re-emerging equatorward of the oceanic frontal zones, which anchor ocean–atmosphere feedbacks. While there is a clear, yet weak, signature from UV irradiance in the atmosphere and upper ocean over the North Atlantic, enhanced MEE precipitation on the other hand does not lead to any systematic changes in the stratospheric circulation, despite its marked chemical signatures.

Sophisticated managers know that reams of data cannot take the place of important information. Planning is necessary to ensure that what is being reported in an organization is necessary and useful and that data are not assembled just because the computer makes it possible. (MLF)

The stratospheric, tropospheric and surface impacts from the 11 year ultraviolet solar spectral irradiance (SSI) variability have been extensively studied using climate models and observations. Here, we demonstrate using idealized model simulations that the Pacific Decadal Oscillation (PDO), which has been shown to impact the tropospheric and stratospheric circulation from sub-decadal to multi-decadal timescales, strongly modulates the solar-induced atmospheric response. To this end, we use a high-top version of the coupled ocean–atmosphere Norwegian Climate Prediction Model forced by the SSI dataset recommended for Coupled Model Intercomparison Project 6. We perform a 24-member ensemble experiment over the solar cycle 23 in an idealized framework. To assess the PDO modulation of the solar signal, we divide the model data into the two PDO phases, PDO+ and PDO−, for each solar (maximum or minimum) phase. By compositing and combining the four categories, we hence determine the component of the solar signal that is independent of the PDO and the modulation of the solar signal by the PDO, along with the solar signal in each PDO phase. Reciprocally, we determine the PDO effect in each solar phase. Our results show that the intensification of the polar vortex under solar maximum is much stronger in the PDO− phase. This signal is transferred into the troposphere, where we find a correspondingly stronger polar jet and weaker Aleutian Low. We further show that the amplification of the solar signal by the PDO− phase is driven by anomalous meridional advection of solar-induced temperature anomalies over northern North America and the North Pacific, which contributes to a decreased meridional eddy heat flux and hence to a decreased vertical planetary wave flux into the stratosphere.

Presents information on the significance of the small mucosal polyps of the rectum. Description of small mucosal polyps; Prevalence of cancer in mucosal polyps; Importance of total excisional-biopsy in identifying mucosal carcinoma.

Introduction: High levels of sick leave and disability pension are significant public health problems with serious consequences for individuals, families and society as a whole. Physical activity and exercise training has many health benefits and is used in both the prevention and treatment of various health complaints and chronic diseases. However, the relationship between physical activity and sickness absence is unresolved. Main part: This article is based on searches in PubMed. Only prospective population studies that examined the association between physical activity/capacity and sickness absence/disability pension were included. Twelve studies reported that physically active persons had a reduced risk of absenteeism or disability pension. Three of these reported stronger associations by vigorous activity compared to moderate activity. Three studies showed that good aerobic capacity reduced the risk of sickness absence. A study reported a positive association between muscular strength and absenteeism. Physically active jobs increased risk of sickness absence, while leisure-time physical activity reduced the risk in one study. However, it varied to what extent studies had adjusted for potential confounding variables. Ending: Prospective population studies indicate that endurance capacity and leisure-time physical activity reduces the risk of sickness absence/disability pension. Vigorous activity appears to reduce the risk more than moderate and light activity, which may be due to a greater impact on health and on physical capacity - which can provide lower relative workloads. Hence, rehabilitation and preventive measures should emphasize regular participation in physical activity and exercise training that includes vigorous physical activity. We propose a model of how physical activity can reduce sickness absence and disability pension.