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Atmospheric Pollution and Environmental Change is an introduction to the major pollutants causing concern today, a description of their sources and how their emissions and concentrations have changed through time. Approaching atmospheric change in the context of its effects on the natural environment, people and the global climate system, Atmospheric Pollution and Environmental Change examines: ·Atmospheric pollution at global, continental and local scales ·The development of policy at national and international levels ·The uses of computer models to help us understand and forecast the behaviour of pollutants and their impacts ·The success (or otherwise) of policies designed to reduce air pollution and the prospects for the future. With extensive references to useful web sites and further reading, Atmospheric Pollution and Environmental Change will be of great benefit to senior undergraduate and postgraduate students.

This paper presents the first extensive reconstruction of precipitation variability in the Lesser Antilles using historical documentary sources. Over 13 250 items of documentation pertaining to Antigua from the period 1769–1890 were consulted, including missionary, plantation and governmental papers as well as contemporary scholarly publications. Based on the predominant meteorological conditions observed throughout the island, each "rain-year" (December–November) was assigned one of five classifications (very wet, wet, "normal", dry and very dry). Local weather references relating to seven plantations in central-eastern Antigua were grouped according to dry (December–April) and wet seasons (May–November), each of which were also categorised in the aforementioned manner. Results comprise individual island-wide and central-eastern Antiguan chronologies of relative precipitation levels, spanning the rain-years 1769–70 to 1889–90 and 1769–70 to 1853–54 respectively. The former is compared with available instrumental data for the years 1870–1890. Significant dry phases are identified in the rain-years 1775–80, 1788–91, 1820–22, 1834–37, 1844–45, 1859–60, 1862–64, 1870–74 and 1881–82, while wet episodes were 1771–74, 1833–34, 1837–38, 1841–44, 1845–46 and 1878–81. Evidence for major wet and dry spells is presented and findings are evaluated within wider historical and palaeoclimatic contexts.

This paper presents the first extensive reconstruction of precipitation variability in the Lesser Antilles using historical documentary sources. Over 13 250 items of documentation pertaining to Antigua from the period 1769–1890 were consulted, including missionary, plantation and governmental papers as well as contemporary scholarly publications. Based on the predominant meteorological conditions observed throughout the island, each "rain-year" (December–November) was assigned one of five classifications (very wet, wet, "normal", dry and very dry). Local weather references relating to seven plantations in central-eastern Antigua were grouped according to dry (December–April) and wet seasons (May–November), each of which were also categorised in the aforementioned manner. Results comprise individual island-wide and central-eastern Antiguan chronologies of relative precipitation levels, spanning the rain-years 1769–70 to 1889–90 and 1769–70 to 1853–54 respectively. The former is compared with available instrumental data for the years 1870–1890. Significant dry phases are identified in the rain-years 1775–80, 1788–91, 1820–22, 1834–37, 1844–45, 1859–60, 1862–64, 1870–74 and 1881–82, while wet episodes were 1771–74, 1833–34, 1837–38, 1841–44, 1845–46 and 1878–81. Evidence for major wet and dry spells is presented and findings are evaluated within wider historical and palaeoclimatic contexts.

The period from 2013 to 2019 was one of relative continuity in policies for physical education (PE), school sport and physical activity (PESSPA) in England. Starting from the advent of the government's flagship PE and Sport Premium (PES Premium) initiative in 2013, the end of the period was reached 20 with renewed uncertainty in 2020 about the future of PESSPA policy. It is therefore an appropriate point for this article to 'take stock' of PESSPA policies and their consequences since 2013. The political science literature on policy design underpins the approach to considering the mix of both policy goals and those instruments used by governments to achieve them. To do so, a comprehensive set of policy documents, published reports, academic literature and empirical research on schools' use of the PES Premium was interrogated. Policy goals articulated by government since 2013 reinforced, rather than resolved, long-standing debates about the purpose of PESSPA. Health-related objectives rose in prominence, but sat uneasily alongside continued commitments to competitive sport. Only a narrow range of the policy instruments available to governments were used in pursuit of their policy goals. PES Premium funding was solely distributed to primary schools, with limited use of regulation and information systems to shape PESSPA provision. These aspects of policy design contributed to increasing reliance on external coaches in primary schools and indicators of a decline in secondary school provision and participation, resonant of prioritisation of short-term approaches over longer-term strategic development. Possibilities for improving future PESSPA policies are considered as a result.

Temporary Removal. ; Composite molten salt-ceramic membranes are promising devices for high-temperature CO2 separation. Intensive material properties impact on separation performance as do membrane geometry (thickness) and microstructure (pore volume fraction, size, connectivity, and tortuosity factor). Although controlling pore size is considered somewhat routine, achieving pore alignment and connectivity is still challenging. Here we report the production of the first gas separation membrane using a porous ceramic matrix obtained from a directionally-solidified magnesium-stabilised zirconia (MgSZ) – MgO fibrilar eutectic as the membrane support. MgO was removed from the parent material by acid-etching to create a porous matrix with highly aligned pores with diameters of ~1 μm. X-ray nano-computed tomography of a central portion (~32,000 μm3) of the support identified ~21% porosity, with all pores aligned within 10° and ~76% percolating along the longest sampled length. Employing the matrix as a support for a carbonate molten salt, a high CO2 permeability of 1.41x10-10 mol.m-1.s-1.Pa-1 at 815 °C was achieved, among the highest reported for supported molten-carbonate membranes (typically 10-12 to 10-10 mol.m-1.s-1.Pa-1 at similar temperatures). We suggest that the high permeability is attributable to the excellent pore characteristics resulting from directional solidification, namely a dense array of parallel, micron-scale pores connecting the feed and permeate sides of the membrane. ; The authors acknowledge the financial support from the Spanish Ministerio de Economía y Competitividad and Feder Funds under project MAT2016-77769R. L. Grima acknowledges financial support through grant BES-2017-079683 associated to the aforementioned project. The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement Number 320725 and from the Engineering & Physical Sciences Research Council (EPSRC) via grants EP/M01486X/1, EP/P007767/1 and EP/P009050/1. PRS acknowledges the Royal Academy of Engineering (CiET1718/59). PRS, DJLB, JJB and MDK acknowledge the support of The Faraday Institution (faraday.ac.uk; EP/ S003053/1). G. Mutch was supported by the Royal Academy of Engineering under the Research Fellowship Scheme and would like to thank the EPSRC for his Doctoral Prize Fellowship (EP/M50791X/1) and Newcastle University for a Newcastle University Academic Track (NUAcT) Fellowship. X-Ray CT acquisition and analysis was supported by UCL and EPSRC under EP/N032888/1. We thank the Servicio General de Apoyo a la Investigación-SAI (Universidad de Zaragoza) for technical support in X-ray diffraction and electron microscopy experiments, Rubén Gotor for technical assistance in sample preparation and R. Lahoz for laser-drilling the YSZ plate that serves as the membrane base. ; Peer reviewed