The atmospheric charged kaon/pion ratio using seasonal variation methods

Observed since the 1950's, the seasonal effect on underground muons is a well studied phenomenon. The interaction height of incident cosmic rays changes as the temperature of the atmosphere changes, which affects the production height of mesons (mostly pions and kaons). The decay of these mesons produces muons that can be detected underground. The production of muons is dominated by pion decay, and previous work did not include the effect of kaons. In this work, the methods of Barrett and MACRO are extended to include the effect of kaons. These efforts give rise to a new method to measure the atmospheric K/$\pi$ ratio at energies beyond the reach of current fixed target experiments. These methods were applied to data from the MINOS far detector. A method is developed for making these measurements at other underground detectors, including OPERA, Super-K, IceCube, Baksan and the MINOS near detector.Comment: 15 pages, 4 figures, submitted to Astropart. Phy

Climate response to a variable gravity-wave source

An investigation examining the response of numerical models containing one of several gravity wave parameterisations to changes in a prescribed tropospheric gravity wave source has been completed. It has been found that the unique interaction between orographic waves and those comprising a broad spectrum, exhibit tell-tale features in an offline environment. The response to these from within the confines of a mechanistic computer model persist and show a significant effect about the southern winter stratosphere. Offline comparisons of the three parameterisations has highlighted significant differences between two of the schemes (Doppler Spread Parameterisation, Medvedev and Klaassen) and the Ultra-Simple Spectral Parameterisation. These are due to; (1) the way in which the latter models wave dissipation and (2) the makeup of the source used. These cannot be resolved by an adjustment of tunable parameters. Comparisons inside a mechanistic model indicate the shortcomings of these offline analyses, as those schemes which showed little difference previously, now differed significantly. The modelled climatic response to changes in the boundary source of gravity waves was largely predictable; warmer/cooler winter/summer polar mesosphere with a reduction in the stratospheric wind jets during times of solstice. These were attributable to circulation changes caused by differing amounts of mesospheric wave drag. However, the extent of the sensitivity of the southern hemisphere winter circulation was unexpected. Other dynamical differences seen included changes in resolved large-scale wave propagation, which in turn affected the nature of sudden warmings and the onset of final warmings. The modulation of a source of vertically propagating gravity waves by stationary planetary scale winds was seen to force similarly sized planetary scale winds within the mesosphere. The modulation of this tropospheric source of gravity waves appears linked with the Tibetan Low during the Asian monsoon season. Similar anomalous winds have been seen in observations and just such a mechanism has been proposed to help explain the existence of these. This has been the first study where such a result has been forced without the introduction of a contrived signal in the source below

Performance Modelling for Climate Models

Peer reviewe

Investigating practice integration of independent prescribing by community pharmacists using normalization process theory: a cross-sectional survey.

Independent prescribing (IP) has not been extensively investigated in community pharmacy (CP). Normalization Process Theory (NPT) constructs help explain how interventions are integrated into practice and include: 'coherence' (understanding), 'cognitive participation' (what promotes engagement), 'collective action' (integration with existing systems), 'reflexive monitoring (evaluation). The aim of this study was to use NPT to investigate the integration of pharmacist IP in CP. NHS Scotland Pharmacy First Plus (PFP) is a community pharmacy IP service. Questionnaire items were developed using the NPT derived Normalisation MeAsure Development (NoMAD) tool for an online survey of all PFP IP pharmacists. Demographic data were analysed descriptively and scale scores (calculated from item scores for the 4 NPT constructs) were used for inferential analysis. There was a 73% (88/120) response rate. Greater than 90% 'strongly agreed' / 'agreed' to NoMAD items relating to most NPT constructs. However, responses to 'collective action' items were diverse with more participants answering 'neither agree nor disagree' or 'disagree'. A statistically significant difference in NPT construct scale scores with significant p-values (ranging from p<0.001 to p=0.033) was shown on all the NPT constructs for the variable 'On average, how often do you consult with patients under the PFP service?'. This theory-based work offers perspectives on IP integration within CP. Despite its geographic focus this work offers insights relevant to wider contexts on IP integration. It shows 'collective action' focused 'organisation' and 'group process' challenges with a need for further work on staff training, resource availability and utilisation, working relationships, communication and management

Tapinoma nigerrimum as safeguard for Italian myrmecofauna against Argentine ant

The Hurst effect plays an important role in many areas such as physics, climate and finance. It describes the anomalous growth of range and constrains the behavior and predictability of these systems. The Hurst effect is frequently taken to be synonymous with Long-Range Dependence (LRD) and is typically assumed to be produced by a stationary stochastic process which has infinite memory. However, infinite memory appears to be at odds with the Markovian nature of most physical laws while the stationarity assumption lacks robustness. Here we use Lorenz's paradigmatic chaotic model to show that regime behavior can also cause the Hurst effect. By giving an alternative, parsimonious, explanation using nonstationary Markovian dynamics, our results question the common belief that the Hurst effect necessarily implies a stationary infinite memory process. We also demonstrate that our results can explain atmospheric variability without the infinite memory previously thought necessary and are consistent with climate model simulations

Modelling the Performance of a Shallow Water Code

Peer reviewe

A momentum budget study of the semi‐annual oscillation in the Whole Atmosphere Community Climate Model

The representation of the semi‐annual oscillation (SAO) in climate models shows a common easterly bias of several tens of metres per second compared to observations. These biases could be due to deficiencies in eastward tropical wave forcing, the position or strength of the climatological summertime jet or the strength/timing of the Brewer–Dobson circulation. This motivates further analysis of the momentum budget of the upper stratosphere within models and a more detailed comparison with reanalyses to determine the origin of the bias. In this study, the transformed Eulerian mean momentum equation is used to evaluate the different forcing terms that contribute to the SAO in the MERRA2 reanalysis dataset. This is then compared with the equivalent analysis using data from a climate simulation of the Whole Atmosphere Community Climate Model (WACCM). The comparison shows that WACCM underestimates eastward forcing by both resolved and parameterised waves at equatorial latitudes when compared with MERRA2 and also has a weaker tropical upwelling above 1 hPa

An unexpected disruption of the atmospheric quasi-biennial oscillation

This is the author accepted manuscript. The final version is available from AAAS via the DOI in this recordWe thank the European Centre for Medium-Range Weather Forecasts for providing ERA-Interim and Operational Analysis data (www.ecmwf.int/en/forecasts) and the Freie Universität Berlin for providing radiosonde data (www.geo.fu-berlin.de/en/met/ag/strat/produkte/qbo). The CMIP5 data was obtained from the British Atmospheric Data Centre (browse.ceda.ac.uk/browse/badc/cmip5). A summary of data used in the study is listed in table S1.One of the most repeatable phenomena seen in the atmosphere, the quasi-biennial oscillation (QBO) between prevailing eastward and westward wind jets in the equatorial stratosphere (approximately 16 to 50 kilometers altitude), was unexpectedly disrupted in February 2016. An unprecedented westward jet formed within the eastward phase in the lower stratosphere and cannot be accounted for by the standard QBO paradigm based on vertical momentum transport. Instead, the primary cause was waves transporting momentum from the Northern Hemisphere. Seasonal forecasts did not predict the disruption, but analogous QBO disruptions are seen very occasionally in some climate simulations. A return to more typical QBO behavior within the next year is forecast, although the possibility of more frequent occurrences of similar disruptions is projected for a warming climate.S.M.O. was supported by UK Natural Environment Research Council grants NE/M005828/1 and NE/P006779/1. A.A.S., J.R.K., and N.B. were supported by the Joint UK Business, Energy and Industrial Strategy/Defra Met Office Hadley Centre Climate Programme (GA01101). A.A.S. and J.R.K. were additionally supported by the EU Seventh Framework Programme SPECS (Seasonal-to-decadal climate Prediction for the improvement of European Climate Services) project

Sudden stratospheric warmings seen in MINOS deep underground muon data

The rate of high energy cosmic ray muons as measured underground is shown to be strongly correlated with upper-air temperatures during short-term atmospheric (10-day) events. The effects are seen by correlating data from the MINOS underground detector and temperatures from the European Centre for Medium Range Weather Forecasts during the winter periods from 2003-2007. This effect provides an independent technique for the measurement of meteorological conditions and presents a unique opportunity to measure both short and long-term changes in this important part of the atmosphere. Citation: Osprey, S., et al. (2009), Sudden stratospheric warmings seen in MINOS deep underground muon data, Geophys. Res. Lett., 36, L05809, doi: 10.1029/2008GL036359

Understanding the mechanisms for tropical surface impacts of the quasi‐biennial oscillation (QBO)

The impact of the quasi-biennial oscillation (QBO) on tropical convection and precipitation is investigated through nudging experiments using the UK Met Office Hadley Center Unified Model. The model control simulations show robust links between the internally generated QBO and tropical precipitation and circulation. The model zonal wind in the tropical stratosphere was nudged above 90 hPa in atmosphere-only and coupled ocean-atmosphere configurations. The convection and precipitation in the atmosphere-only simulations do not differ between the experiments with and without nudging, which may indicate that SST-convection coupling is needed for any QBO influence on the tropical lower troposphere and surface. In the coupled experiments, the precipitation and sea-surface temperature relationships with the QBO phase disappear when nudging is applied. Imposing a realistic QBO-driven static stability anomaly in the upper-troposphere lower-stratosphere is not sufficient to simulate tropical surface impacts. The nudging reduced the influence of the lower troposphere on the upper branch of the Walker circulation, irrespective of the QBO, indicating that the upper tropospheric zonal circulation has been decoupled from the surface by the nudging. These results suggest that grid-point nudging mutes relevant feedback processes occurring at the tropopause level, including high cloud radiative effects and wave mean flow interactions, which may play a key role in stratospheric-tropospheric coupling