Queen's Printer Research Articles

A Simple and Rapid Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry Method for the Quantitation of Pharmaceuticals and Related Compounds in Mussels and Oysters.

A simple, rapid ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been developed and optimized for the quantitation of a range of pharmaceuticals, metabolites, and related bioactive compounds in the bivalve mollusc species mussels (Mytilus edulis) and Pacific oysters (Crassostrea gigas). Shellfish tissues were extracted using a simple solvent-based extraction method prior to concentration and purification by pass-through solid-phase extraction and quantified using stable isotope dilution MS/MS. The analytes covered a range of therapeutic classes including antidepressants, anticonvulsants, beta-blockers, and antiplatelets. Of the 34 compounds included in the present study initially, 28 compounds were found to demonstrate acceptable performance. Performance was assessed by examining extraction efficiencies, matrix effects, sensitivity, and within- and between-batch precision. The results show that as indicated by acceptable HorRat and accuracy values, the method is fit for purpose. Application of this method to environmental mussel and oyster samples revealed the presence of 12 compounds at quantifiable concentrations, with the antidepressant sertraline being present at the highest level, reaching a concentration of 6.12 ng/g in mussel tissue. © 2021 Crown copyright. Environmental Toxicology and Chemistry 2021;40:3263-3274. © 2021 SETAC. This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

Pregnancy-Related Change in pQCT and Bone Biochemistry in a Population With a Habitually Low Calcium Intake.

In pregnancy, changes in maternal calcium (Ca) economy occur to satisfy fetal Ca demand. It is unclear whether maternal mineral reserves facilitate these requirements and no data exist from sub-Saharan Africa. The aim was to determine skeletal changes with peripheral quantitative computed tomography (pQCT) and bone biochemistry between early second and third trimesters. Pregnant rural Gambians aged 18 to 45 years (n=467) participating in a trial of antenatal nutritional supplements (ISRCTN49285450) had pQCT scans and blood collections at mean (SD) 14 (3) and 31 (1) weeks' gestation. Outcomes were pQCT: radius/tibia 4% total volumetric bone mineral density (vBMD), trabecular vBMD, total cross-sectional area (CSA), 33%/38% radius/tibia cortical vBMD, bone mineral content (BMC), total CSA; biochemistry: collagen type 1 cross-linked β-C-telopeptide (β-CTX), type 1 procollagen N-terminal (P1NP), parathyroid hormone (PTH), and 1,25(OH)2 D. Independent t tests tested whether pooled or within-group changes differed from 0. Multiple regression was performed adjusting for age. Data for change are expressed as mean (confidence interval [CI] 2.5, 97.5%). Radius trabecular vBMD, cortical vBMD, and BMC increased by 1.15 (0.55, 1.75)%, 0.41 (0.24, 0.58)%, and 0.47 (0.25, 0.69)%. Tibia total and trabecular vBMD increased by 0.34 (0.15, 0.54)% and 0.46 (0.17, 0.74)%, while tibia cortical vBMD, BMC, and cortical CSA increased by 0.35 (0.26, 0.44)%, 0.55 (0.41, 0.68)% and 0.20 (0.09, 0.31)%, respectively. CTX, PTH, and 1,25(OH)2 D increased by 23.0 (15.09, 29.29)%, 13.2 (8.44, 19.34)%, and 21.0 (17.67, 24.29)%, while P1NP decreased by 32.4 (-37.19, -28.17)%. No evidence of mobilization was observed in the peripheral skeleton. Resorption, although higher in late versus early gestation, was lower throughout pregnancy compared with non-pregnant non-lactating (NPNL) in the same community. Formation was lower in late pregnancy than in early, and below NPNL levels. This suggests a shift in the ratio of resorption to formation. Despite some evidence of change in bone metabolism, in this population, with habitually low Ca intakes, the peripheral skeleton was not mobilized as a Ca source for the fetus. © 2021 crown copyright . Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). The article published with the permission of the Controller of HMSO and the Queen's Printer of Scotland..

Tibial Macrostructure and Microarchitecture Adaptations in Women During 44 Weeks of Arduous Military Training.

Bone adapts to unaccustomed, high-impact loading but loses mechanosensitivity quickly. Short periods of military training (≤12 weeks) increase the density and size of the tibia in women. The effect of longer periods of military training, where the incidence of stress fracture is high, on tibial macrostructure and microarchitecture in women is unknown. This observational study recruited 51 women (age 19 to 30 years) at the start of 44 weeks of British Army Officer training. Tibial volumetric bone mineral density (vBMD), geometry, and microarchitecture were measured by high-resolution peripheral quantitative computed tomography (HRpQCT). Scans of the right tibial metaphysis (4% site) and diaphysis (30% site) were performed at weeks 1, 14, 28, and 44. Measures of whole-body areal bone mineral density (aBMD) were obtained using dual-energy X-ray absorptiometry (DXA). Blood samples were taken at weeks 1, 28, and 44, and were analyzed for markers of bone formation and resorption. Trabecular vBMD increased from week 1 to 44 at the 4% site (3.0%, p < .001). Cortical vBMD decreased from week 1 to 14 at the 30% site (-0.3%, p < .001). Trabecular area decreased at the 4% site (-0.4%); trabecular bone volume fraction (3.5%), cortical area (4.8%), and cortical thickness (4.0%) increased at the 4% site; and, cortical perimeter increased at the 30% site (0.5%) from week 1 to 44 (p ≤ .005). Trabecular number (3.5%) and thickness (2.1%) increased, and trabecular separation decreased (-3.1%), at the 4% site from week 1 to 44 (p < .001). Training increased failure load at the 30% site from week 1 to 44 (2.5%, p < .001). Training had no effect on aBMD or markers of bone formation or resorption. Tibial macrostructure and microarchitecture continued to adapt across 44 weeks of military training in young women. Temporal decreases in cortical density support a role of intracortical remodeling in the pathogenesis of stress fracture. © 2021 Crown copyright. Journal of Bone and Mineral Research © 2021 American Society for Bone and Mineral Research (ASBMR). This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

Pregnancy-Related Bone Mineral and Microarchitecture Changes in Women Aged 30 to 45 Years.

ABSTRACTAt birth, the neonatal skeleton contains 20 to 30 g calcium (Ca). It is hypothesized maternal bone mineral may be mobilized to support fetal skeletal development, although evidence of pregnancy‐induced mineral mobilization is limited. We recruited healthy pregnant (n = 53) and non‐pregnant non‐lactating (NPNL; n = 37) women aged 30 to 45 years (mean age 35.4 ± 3.8 years) and obtained peripheral quantitative computed tomography (pQCT) and high‐resolution pQCT (HR‐pQCT) scans from the tibia and radius at 14 to 16 and 34 to 36 weeks of pregnancy, with a similar scan interval for NPNL. Multiple linear regression models were used to assess group differences in change between baseline and follow‐up; differences are expressed as standard deviation scores (SDS) ± SEM. Decreases in volumetric bone mineral density (vBMD) outcomes were found in both groups; however, pregnancy‐related decreases for pQCT total and trabecular vBMD were −0.65 ± 0.22 SDS and −0.50 ± 0.23 SDS greater (p < .05). HR‐pQCT total and cortical vBMD decreased compared with NPNL by −0.49 ± 0.24 SDS and −0.67 ± 0.23 SDS, respectively; trabecular vBMD decreased in both groups to a similar magnitude. Pregnancy‐related changes in bone microarchitecture significantly exceeded NPNL change for trabecular number (0.47 ± 0.23 SDS), trabecular separation (−0.54 ± 0.24 SDS), cortical thickness (−1.01 ± 0.21 SDS), and cortical perimeter (0.78 ± 0.23 SDS). At the proximal radius, cortical vBMD and endosteal circumference increased by 0.50 ± 0.23 SDS and 0.46 ± 0.23 SDS, respectively, compared with NPNL, whereas cortical thickness decreased −0.50 ± 0.22 SDS. Pregnancy‐related decreases in total and compartment‐specific vBMD exceed age‐related change at the distal tibia. Changes at the radius were only evident with pQCT at the cortical‐rich proximal site and suggest endosteal resorption. Although the magnitude of these pregnancy‐related changes in the appendicular skeleton are small, if they reflect global changes across the skeleton at large, they may contribute substantially to the Ca requirements of the fetus. © 2020 Crown copyright. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

UK annual weather summary

WeatherVolume 74, Issue 2 p. 59-59 Seasonal Weather Summary UK annual weather summary National Climate Information Centre, National Climate Information Centre Met Office, ExeterSearch for more papers by this author National Climate Information Centre, National Climate Information Centre Met Office, ExeterSearch for more papers by this author First published: 05 February 2019 https://doi.org/10.1002/wea.3458 This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume74, Issue2February 2019Pages 59-59 RelatedInformation

UK seasonal weather summary Summer 2018

WeatherVolume 73, Issue 10 p. 321-321 Seasonal Weather Summary UK seasonal weather summary Summer 2018 National Climate Information Centre, National Climate Information Centre Met Office, ExeterSearch for more papers by this author National Climate Information Centre, National Climate Information Centre Met Office, ExeterSearch for more papers by this author First published: 09 October 2018 https://doi.org/10.1002/wea.3414 This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland. Comparisons/maps are based upon provisional data. Temperature and rainfall series from 1910, and sunshine from 1929. See http://www.metoffice.gov.uk/climate for updates and further information Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume73, Issue10October 2018Pages 321-321 RelatedInformation

UK seasonal weather summary Autumn 2017

WeatherVolume 73, Issue 1 p. 19-19 Seasonal Weather Summary UK seasonal weather summary Autumn 2017 First published: 10 January 2018 https://doi.org/10.1002/wea.3209 This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume73, Issue1January 2018Pages 19-19 RelatedInformation

Foreword

Nutrition BulletinVolume 36, Issue 4 p. 415-415 Foreword Professor Sir John Beddington CMG, FRS, Professor Sir John Beddington CMG, FRS Chief Scientific Adviser to HM Government, and Head of the Government Office for ScienceSearch for more papers by this author Professor Sir John Beddington CMG, FRS, Professor Sir John Beddington CMG, FRS Chief Scientific Adviser to HM Government, and Head of the Government Office for ScienceSearch for more papers by this author First published: 08 November 2011 https://doi.org/10.1111/j.1467-3010.2011.01930.x This article ‘Foreword’ was written by Professor Sir John Beddington of the Goverment Office for Science. It is published with the permission of the Controller of HMSO the Queen's Printer for Scotland. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume36, Issue4Special Issue: Achieving a healthy sustainable diet: an integrated approach. Guest Editor - H RileyDecember 2011Pages 415-415 RelatedInformation

Topography effects and monatomic ion sputtering of undulating surfaces, particles and large nanoparticles: Sputtering yields, effective sputter rates and topography evolution

AbstractAn analysis is provided of the change in topography and consequent apparent change in sputtering yields of surfaces as a result of ion sputtering using Yamamura et al.'s model for the angular dependence of the sputtering yield for monatomic primary ions. This is extended to provide a general scheme for any monatomic primary ion and any amorphous elemental solid target. Details are provided of the topographic changes for surfaces with an undulating cosine profile sputtered with primary ions normal to, and at 45° to, the average surface and also for spherical particles. Smoothing occurs at normal incidence and both smoothing and roughening can occur at 45°. Predictions show how the sputtering rate of the material varies with the depth sputtered as a result of the topographical changes, the rate either increasing or decreasing. The effect of roughening usually increases the sputtering rate with values increasing up to four times. The effect of sample rotation is a fast smoothing. Conditions are described for the optimal profiling of particles with a layered structure and calculated profiles are evaluated. The effect of rotation on particles is discussed in relation to different instrumental geometries. In this work, recoil mixing, redeposition, diffusion and the topographic effects at the size of the individual ion cascade are ignored. © Crown copyright 2011. Reproduced by permission of the Controller of HMSO and the Queen's printer for Scotland.

Cloud detection in Meteosat Second Generation imagery at the Met Office

AbstractThe Met Office has been using data from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on board the Meteosat Second Generation (MSG) satellites for nowcasting, assimilation in numerical weather prediction (NWP) and for providing guidance to forecasters since September 2004. This paper describes the cloud mask derived from MSG imagery which is used by all downstream products. The Met Office SEVIRI mask is compared with that of the Nowcasting Satellite Applications Facility (SAFNWC), and with the Moderate Resolution Imaging Spectro‐Radiometer (MODIS) cloud mask. These comparisons show good agreement between the cloud masks: the Met Office and SAFNWC masks are in accord with the MODIS mask for 90.65% and 89.69% of SEVIRI pixels tested, respectively. © Crown Copyright 2011. Published with the permission of the Controller of HMSO and the Queen's Printer for Scotland

A comparison of SIMS and DESI and their complementarities

AbstractThe most prevalent of the ambient mass spectrometries, desorption electrospray ionisation (DESI), which provides highly sensitive mass spectrometry from surfaces without the constraint of vacuum, is compared with secondary ion mass spectrometry (SIMS). The potential of DESI has been demonstrated in a wide range of application areas, including forensics, homeland security, counterfeit detection of pharmaceuticals and biological analysis. As with all techniques, there are some disadvantages: DESI cannot generally desorb molecules that are strongly bound to surfaces; there are low signals from molecules with low ionisation efficiency; and the spatial resolution is currently limited to approximately 100 µm. For these studies, SIMS is more powerful, but the two mass spectrometries are highly complementary. DESI uses a gentler desorption mechanism to remove material from the surface than the sputtering involved in SIMS. In particular, large fragile molecules can be detected intact, rather than heavily fragmented as in SIMS. Here, we illustrate the complementarities of SIMS and DESI for the analysis of 18 industrially relevant organic molecules. © Crown copyright 2010. Reproduced by permission of the Controller of HMSO and the Queen's printer for Scotland.

Parametrization of area cloud fraction

AbstractComparisons of radiosonde data to model profiles show that the relative coarseness of the vertical grid can lead to poorly resolved changes in thermodynamic properties. This can lead to the model underestimating cloud cover. A parametrization for area cloud fraction, compatible with a prognostic cloud scheme, is developed and tested. The parametrization is then implemented in a general circulation model and used to produce a weather forecast and a climate simulation. The simulated cloud cover is improved in both models, whilst feedbacks within the climate model lead to an improvement in the surface temperature, particularly in the Northern‐Hemisphere winter. © Crown Copyright 2010. Published with the permission of the Controller of HMSO and the Queen's Printer for Scotland

A comparison of the climate impacts of geoengineering by stratospheric SO2 injection and by brightening of marine stratocumulus cloud

AbstractWe examine the climate impact of geoengineering via two different methods, namely, stratospheric SO2 injection and increasing reflectivity of marine stratocumulus clouds. Although both methods appear capable, in principle, of counteracting the global mean warming due to increases in greenhouse gas concentrations, significant changes in regional climate still result. The extent of this regional climate change appears linked to the location and degree of inhomogeneity of the radiative flux perturbations produced by each geoengineering method. © Crown Copyright 2010. Published with the permission of the Controller of HMSO and the Queen's Printer for Scotland

Alberta mercury regulation for coal-fired power plants

Alberta stakeholders, through the Province's Clean Air Strategic Alliance (CASA), identified mercury as the pollutant of highest priority for control from coal-fired power plants. Working with CASA, the Province finalized a new Mercury Emission from Coal-Fired Power Plants Regulation [ Mercury Emissions From Coal-fired Power Plants Regulation, March 2006, Alberta Regulation 34/2006, Alberta Queen's Printer, Regulation may be found at http://www.gov.ab.ca/qp.] [1]. The regulation places the province at the forefront of controlling mercury emissions from the sector on a global level by driving actions to reduce mercury emissions from existing coal-fired power plants in the province by at least 50% by 2010. Requirements also include continuous improvement provisions for further mercury reductions beyond 2010 based on technology advancement over the next 10 years. This paper summarises the regulation, the work the province undertook at the provincial and national level in its development, and status of implementation actions.

British Columbia's Northern Interior Forests: Warren Root Collar Weevil Stand Establishment Decision Aid

Warren root collar weevil (Hylobius warreni) is a commonly occurring insect found in most of British Columbia and as far north as the Northwest Territories. This weevil affects many tree species and is found in forest stands of any age, although its impact as a disturbance agent is most important in lodgepole pine stands. Engelmann and white spruce are also common hosts, but incidence levels have not been high enough with these species to cause reforestation issues. Incidence levels in lodgepole pine stands commonly exceed 30%, although mortality levels are generally far less and occur in younger stands (5-20 years of age). Recent research suggests that a link exists between stands affected by mountain pine beetle (MPB) and root collar weevil. In one study, the incidence of weevil-attacked trees was elevated in young plantations adjacent to mature stands that had sustained high levels of MPB-caused mortality. An understanding of the weevil's biology and the identification of high-hazard stand conditions for both insect species are essential to successfully avoid regeneration issues. Most treatments involve mitigation measures applied during stand establishment. The Stand Establishment Decision Aid (SEDA) format has been used to extend information on a variety of vegetation and forest health concerns in British Columbia. The two-page SEDA presented in this extension note was developed to summarize information that northern forest managers will need to manage the impacts of the Warren root collar weevil. The following pages describe susceptible stand types, weevil biology, hazard ratings, forest productivity considerations, and appropriate management practices. A resource and reference list that readers can use to find more detailed information is also included. Most reference material that is not available online can be ordered through libraries or the Queen's Printer at: www.qp.gov.bc.ca

British Columbia's Forests White Pine Blister Rust Forest Health Stand Establishment Decision Aid

White pine blister rust (Cronartium ribicola) is an introduced disease affecting five-needle pines throughout North America. Like other non-native pests, its impact on the native hosts has been dramatic, decimating species such as western white pine in both number and distribution. Because of its prevalence, white pines have been removed from commercial forestry consideration in most areas. This is unfortunate as western white pine is an excellent substitute for Douglas-fir in areas prone to laminated root disease. It can also command a premium price. To mitigate disease impact and permit management, a good understanding of the biology of C. ribicola is necessary.The Stand Establishment Decision Aid (SEDA) format has been used to extend information on various vegetation and forest health concerns in British Columbia. This decision aid summarizes information that relates current management regimes to the spread and effects of white pine blister rust. The first page provides general information, hazard ratings for the biogeoclimatic zones and subzones of British Columbia, and biological considerations for white pine blister rust. The second page outlines the implications to silviculture and the various techniques used to manage the disease. This page also includes a resource and reference list to provide readers with more detailed information. Reference material that is not available online can be ordered through libraries or the Queen's Printer at: www.qp.gov.bc.ca

British Columbia's Northern Interior Forests Dothistroma Stand Establishment Decision Aid

Dothistroma needle blight, also known as red band needle blight, is caused by the fungus Dothistroma septosporum. It affects over 60 species of pine in 45 countries and is considered the most destructive pine needle disease in the world. All pine species native to British Columbia are susceptible and the fungus is widely distributed wherever host species can be found. Infection is caused by rain splash and air dispersal of the spores. In the southern hemisphere, it has been a major problem for decades. In British Columbia, however, damage levels from this pathogen have historically been low. Recent widespread defoliation, mortality (including mature tree mortality), and plantation failure caused by Dothistroma in the northwest portion of the province may be a result of changing climatic conditions that allow the fungus to develop in a way that was not previously possible.The Stand Establishment Decision Aid (SEDA) format has been used to extend information on a variety of vegetation and forest health concerns in British Columbia. The two-page SEDA presented in this extension note was developed to summarize information that provincial forest managers will need to mitigate the impacts of Dothistroma needle blight. The first page provides information on susceptible stand types, disease biology, hazard ratings, and appropriate management practices. The second page outlines forest productivity considerations and risks to human health. A resource and reference list that readers can use to find more detailed information is also included. Most reference material that is not available online can be ordered through libraries or the Queen's Printer at: www.qp.gov.bc.ca

Unsteady exact solutions of the flow equations for three‐dimensional spherical atmospheres

AbstractTime‐dependent, closed‐form solutions of the 3D Euler equations describing motion relative to a uniformly rotating coordinate frame are derived. The spherical geopotential approximation is applied but not the shallow‐atmosphere and hydrostatic approximations. The solutions correspond to cyclostrophically and hydrostatically balanced vortices that are steady in inertial space and whose symmetry axes do not coincide with the rotation axis of the coordinate frame. The inertial‐frame flow velocities are readily transformed to a precisely spherical rotating coordinate system in which the 3D Euler equations contain centrifugal as well as Coriolis terms. In this form the solutions may be used to test numerical models formulated in spherical coordinates under the spherical geopotential approximation, so long as the centrifugal terms are explicitly included as forcing terms. The development is repeated for the hydrostatic and non‐hydrostatic primitive equations (with the shallow‐atmosphere approximation) and for the shallow‐water equations. In the latter case, the required explicit centrifugal force may be provided by a zonally symmetric addition to the free surface height, with an identically equal orographic elevation to ensure conservation of mass. The solutions are then identical to the unsteady shallow‐water solutions of Läuter et al. that inspired this study. ©Crown Copyright 2008. Reproduced with the permission of the Controller of HMSO and the Queen's Printer for Scotland. Published by John Wiley &amp; Sons, Ltd.

British Columbia's Coastal Forests Variable Retention Decision Aid for Biodiversity and Habitat Retention

Variable retention (VR) refers to a strategy that is designed to retain biological legacies, such as large old trees, snags, and downed logs, at harvest to create and/or maintain structurally complex stands with a range of silvicultural systems. The retention system is a new silvicultural system (Forest Practices Code – Operational and Site Planning Regulations) designed for use under a VR strategy (Mitchell and Beese 2002). By retaining certain structural elements, habitat carrying capacity can be maintained and connectivity can be conserved over the landscape. The planning and implementation of VR is a complex process, with many potential risks that must be understood if one is to successfully achieve multiple management objectives. With the implementation of the retention system in coastal British Columbia, researchers have generated much information and learned many lessons. This Stand Establishment Decision Aid (SEDA) is intended to provide general guidance and points to consider when implementing the various structures (aggregated or dispersed) that are associated with the retention system in British Columbia's coastal forests. Additional information related to retention and variable retention can be found in the Resource and Reference list at the end of this document. It is important to note that the list provided in this reference section is not exhaustive and more information is available, but not necessarily cited. Reference material that is not available on-line can be ordered through libraries or the Queen's Printer at: http://www.qp.gov.bc.ca.

Operational NWP assimilation of GPS radio occultation data

AbstractSince 26 September 2006, refractivity profiles from the CHAMP and GRACE‐A satellites have been assimilated in the Met Office operational global numerical weather prediction system. This article presents the results of two experiments, which aim to determine the potential impact on the forecast resulting from the assimilation of this new dataset, and goes on to describe the Met Office operational implementation. Despite the limited number of occultations available for assimilation, the experiments show a significant positive impact on upper troposphere and lower stratosphere temperature and geopotential height fields, mid‐tropospheric geopotential heights and pressure at mean sea level in the Southern Hemisphere. © Crown Copyright 2008. Reproduced with permission of Controller of HMSO and Queen's Printer for Scotland. Published by John Wiley &amp; Sons, Ltd.