We report the results of a structured expert elicitation to identify the most likely types of potential food system disruption scenarios for the UK, focusing on routes to civil unrest. We take a backcasting approach by defining as an end-point a societal event in which 1 in 2000 people have been injured in the UK, which 40% of experts rated as “Possible (20–50%)”, “More likely than not (50–80%)” or “Very likely (>80%)” over the coming decade. Over a timeframe of 50 years, this increased to 80% of experts. The experts considered two food system scenarios and ranked their plausibility of contributing to the given societal scenario. For a timescale of 10 years, the majority identified a food distribution problem as the most likely. Over a timescale of 50 years, the experts were more evenly split between the two scenarios, but over half thought the most likely route to civil unrest would be a lack of total food in the UK. However, the experts stressed that the various causes of food system disruption are interconnected and can create cascading risks, highlighting the importance of a systems approach. We encourage food system stakeholders to use these results in their risk planning and recommend future work to support prevention, preparedness, response and recovery planning.

Record-breaking high temperatures were experienced across the United Kingdom during summer 2022. The impacts of these extreme climatic conditions were felt across the food system, including increased energy costs for cold storage, the failure of refrigeration systems in numerous retail facilities, and impacts on livestock including heat stress. Future climate projections indicate an increased likelihood and duration of extreme high temperatures like those experienced in 2022. Learning from the impacts of the 2022 heatwave on the United Kingdom food system can help identify adaptations that build resilience to climate change. We explore the impacts through two case studies (United Kingdom poultry and wheat sectors), discuss potential adaptation options required for a climate-resilient, net-zero United Kingdom food system and consider future research needs. United Kingdom chicken meat production was 9% lower in July 2022 than July 2021; in contrast, energy costs increased for both production and refrigeration. Potential heatwave adaptation measures for poultry include transitioning to heat tolerant chicken breeds, lower stocking density, dehumidification cooling and misting systems, nutritional supplements, and improving retail refrigeration resilience and efficiency. United Kingdom wheat yields were 8% higher in 2022 than the 2017–2021 average. Increases were observed in every United Kingdom region but were least in the South and East where the heatwave intensity was strongest. Future adaptation measures to avoid negative impacts of summer heat stress on winter wheat could include earlier maturing and heat/drought tolerant varieties, earlier autumn sowing, targeted irrigation for drought around anthesis, and soil and water conservation measures.

Sub-Saharan Africa is one of the most food-insecure regions in the world, and is particularly vulnerable to the impacts of extreme climate events and climate change. To gain a better understanding of the present-day likelihood of extreme seasonal temperature and rainfall events, and their joint occurrence, we apply the UNprecedented Simulated Extremes using ENsembles (UNSEEN) approach to a large ensemble of high-resolution initialised climate simulations in three countries of Sub-Saharan Africa: Tanzania, Zambia and South Africa. We assess the annual likelihood of unprecedented seasonal temperature and precipitation extremes during the maize growing season (October-April), as key variables for maize productivity , and investigate the large-scale dynamics of the climate system that govern their occurrence. We estimate that there is a 3-4% chance per year of exceeding the present-day seasonal temperature records in the maize growing regions of these countries, and a 1-3.5% chance per year of exceeding the present-day seasonal precipitation records. Conversely, whilst we find a 2% and 5% chance per year of subceeding the present-day seasonal precipitation records in Zambia and Tanzania respectively, we find a very low chance (0-1% per year) of subceeding the present-day seasonal precipitation records in South Africa. We also use the large ensemble to investigate the large-scale dynamics of the climate extremes, finding that high temperature extremes tend to be associated with El Niño and positive IOD/SIOD events and low temperature extremes with La Niña and negative IOD/SIOD events. The drivers of precipitation extremes, however, differ between the countries. In South Africa, high (low) precipitation extremes are associated with La Niña (El Niño) events but otherwise the influence on extremes of ENSO, and even more so the IOD/SIOD, is weak or not seen in the ensemble, which invites further investigation. To explore implications for growing maize in these regions, we convert our unprecedented seasonal temperature estimates to daily maximum temperatures and our seasonal precipitation estimates to monthly precipitation indices and compare to climatic thresholds for maize. Combined with projected changes to crop suitability in much of sub-Saharan Africa, our analysis suggests the need for significant adaptation strategies that build food system resilience in the near and longer term.

Wheat is a major crop worldwide, mainly cultivated for human consumption and animal feed. Grain quality is paramount in determining its value and downstream use. While we know that climate change threatens global crop yields, a better understanding of impacts on wheat end-use quality is also critical. Combining quantitative genetics with climate model outputs, we investigated UK-wide trends in genotypic adaptation for wheat quality traits. In our approach, we augmented genomic prediction models with environmental characterisation of field trials to predict trait values and climate effects in historical field trial data between 2001 and 2020. Addition of environmental covariates, such as temperature and rainfall, successfully enabled prediction of genotype by environment interactions (G × E), and increased prediction accuracy of most traits for new genotypes in new year cross validation. We then extended predictions from these models to much larger numbers of simulated environments using climate scenarios projected under Representative Concentration Pathways 8.5 for 2050-2069. We found geographically varying climate change impacts on wheat quality due to contrasting associations between specific weather covariables and quality traits across the UK. Notably, negative impacts on quality traits were predicted in the East of the UK due to increased summer temperatures while the climate in the North and South-west may become more favourable with increased summer temperatures. Furthermore, by projecting 167,040 simulated future genotype-environment combinations, we found only limited potential for breeding to exploit predictable G × E to mitigate year-to-year environmental variability for most traits except Hagberg falling number. This suggests low adaptability of current UK wheat germplasm across future UK climates. More generally, approaches demonstrated here will be critical to enable adaptation of global crops to near-term climate change.

A new method is employed to measure the neutral current cross section up to Bjorken-x values of one with the ZEUS detector at HERA using an integrated luminosity of 65.1 pb-1 for e+p collisions and 16.7 pb-1 for e-p collisions at sqrts=318 GeV and 38.6 pb-1 for e+p collisions at sqrts=300 GeV. Cross sections have been extracted for Q2 >= 648 GeV2 and are compared to predictions using different parton density functions. For the highest x bins, the data have a tendency to lie above the expectations using recent parton density function parametrizations.

Inclusive-jet and dijet differential cross sections have been measured in neutral current deep inelastic ep scattering for exchanged boson virtualities Q2 > 125 GeV2 with the ZEUS detector at HERA using an integrated luminosity of 82 pb-1. Jets were identified in the Breit frame using the kt cluster algorithm. Jet cross sections are presented as functions of several kinematic and jet variables. The results are also presented in different regions of Q2. Next-to-leading-order QCD calculations describe the measurements well. Regions of phase space where the theoretical uncertainties are small have been identified. Measurements in these regions have the potential to constrain the gluon density in the proton when used as inputs to global fits of the proton parton distribution functions.

The production of energetic neutrons in ep collisions has been studied with the ZEUS detector at HERA. The neutron energy and p(T)(2) distributions were measured with a forward neutron calorimeter and tracker in a 40 pb(-1) sample of inclusive deep inelastic scattering (DIS) data and a 6 pb(-1) sample of photoproduction data. The neutron yield in photoproduction is suppressed relative to DIS for the lower neutron energies and the neutrons have a steeper p(T)(2)distribution, consistent with the expectation from absorption models. The distributions are compared to HERA measurements of leading protons. The neutron energy and transversemomentum distributions in DIS are compared to Monte Carlo simulations and to the predictions of particle exchange models. Models of pion exchange incorporating absorption and additional secondary meson exchanges give a good description of the data. (c) 2007 Elsevier B.V. All rights reserved.

The photoproduction of dijet events, where the two jets with the highest transverse energy are separated by a large gap in pseudorapidity, have been studied with the ZEUS detector using an integrated luminosity of 39 pb^-1. Rapidity-gap events are defined in terms of the energy flow between the jets, such that the total summed transverse energy in this region is less than some value E_ T^ CUT. The data show a clear excess over the predictions of standard photoproduction models. This is interpreted as evidence for a strongly interacting exchange of a color-singlet object. Monte Carlo models which include such a color-singlet exchange are able to describe the data.

The cross section for high-E-T dijet production in photoproduction has been measured with the ZEUS detector at HERA using an integrated luminosity of 81.8 pb(-1). The events were required to have a virtuality of the incoming photon, Q(2), of less than 1 GeV2 and a photon-proton center-of-mass energy in the range 142 < W-gamma p < 293 GeV. Events were selected if at least two jets satisfied the transverse-energy requirements of E-T(jet1)> 20 GeV and E-T(jet2)> 15 GeV and pseudorapidity (with respect to the proton beam direction) requirements of -1

Bose-Einstein correlations of charged and neutral kaons have been measured in e(+/-) p deep inelastic scattering with an integrated luminosity of 121 pb(-1) using the ZEUS detector at HERA. The two-particle correlation function was studied as a function of the four-momentum difference of the kaon pairs, Q(12) = root -(P-1-P-2)(2), assuming a Gaussian shape for the particle source. The values of the radius of the production volume, r, and of the correlation strength lambda, were obtained for both neutral and charged kaons. The radii for charged and neutral kaons are similar and are consistent with those obtained at LEP. (c) 2007 Elsevier B.V. All rights reserved.

The distribution of the azimuthal angle of charged and neutral hadrons relative to the lepton plane has been studied for neutral current deep inelastic ep scattering using an integrated luminosity of 45 pb -1 taken with the ZEUS detector. The kinematic range is 100<Q 2 <8000 GeV 2 , 0.2<y<0.8 and 0.01<x<0.1 where Q 2 is the virtuality of the exchanged boson, y is the inelasticity and x is the Bjorken variable. The measurements were made in the hadronic centre-of-mass system. The analysis exploits the energy-flow method, which allows the measurement to be made over a larger range of pseudorapidity compared to previous results. The dependence of the moments of the azimuthal distributions on the pseudorapidity and minimum transverse energy of the final-state hadrons are presented. Although the predictions from next-to-leading-order QCD describe the data better than do the Monte Carlo models incorporating leading-logarithm parton showers, they still fail to describe the magnitude of the asymmetries. This suggests that higher-order calculations may be necessary to describe these data.

Dijet and trijet production in deep inelastic ep scattering has been measured in the phase space region 10 < Q(2) < 100 GeV2 and 10(-4) < x(Bj) < 10(-2) using an integrated luminosity of 82 pb(-1) collected by the ZEUS experiment. The high statistics have made possible detailed studies of multijet production at low xBj. The dependence of dijet and trijet production on the kinematic variables Q(2) and x(Bj) and on the jet variables E-T,HCM(jet) and eta(jet)(LAB) is well described by perturbative QCD calculations which include NLO corrections. To investigate possible deviations with respect to the collinear factorisation approximation used in the standard pQCD approach, measurements of the correlations between the two jets with highest E-T,HCM(jet) have been made. At low x(Bj), measurements of dijet production with low azimuthal separation are reproduced by the perturbative QCD calculations provided that higher-order terms (O(alpha(3)(s))) are accounted for. Such terms increase the predictions of pQCD calculations by up to one order of magnitude when the two jets with the highest E-T,HCM(jet1,2) are not balanced in transverse momentum. This demonstrates the importance of higher-order corrections in the low-x(Bj) region.

The production of beauty quarks with a D*+- and a muon in the final state has been measured with the ZEUS detector at HERA using an integrated luminosity of 114 pb-1. Low transverse-momentum thresholds for the muon and D* meson allow a measurement of beauty production closer to the production threshold than previous measurements. The beauty signal was extracted using the charge correlations and angular distributions of the muon with respect to the D* meson. Cross sections for photoproduction and deep inelastic scattering are somewhat higher than, but compatible with, next-to-leading-order QCD predictions, and compatible with other measurements.

The first observation of d(d) in ep collisions in the DIS regime at HERA is presented. The production rate of d(d) is smaller than that for p(p) by three orders of magnitude, which is in broad agreement with other experiments.

Diffractive photoproduction of D(2010) mesons was measured with the ZEUS detector at the ep collider HERA, using an integrated luminosity of 78.6 pb. The D mesons were reconstructed in the kinematic range: transverse momentum pT (D ) > 1.9 GeV and pseudorapidity |η(D∗)| < 1.6, using the decay D → Dπ s followed by D → Kπ (+c.c.). Diffractive events were identified by a large gap in pseudorapidity between the produced hadronic state and the outgoing proton. Cross sections are reported for photon-proton centre-ofmass energies in the range 130 < W < 300 GeV and for photon virtualities Q < 1 GeV, in two ranges of the Pomeron fractional momentum xIP < 0.035 and xIP < 0.01. The relative contribution of diffractive events to the inclusive D(2010) photoproduction cross section is about 6%. The data are in agreement with perturbative QCD calculations based on various parameterisations of diffractive parton distribution functions. The results are consistent with diffractive QCD factorisation. The ZEUS Collaboration S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida Argonne National Laboratory, Argonne, Illinois 60439-4815, USA n M.C.K. Mattingly Andrews University, Berrien Springs, Michigan 49104-0380, USA M. Jechow, N. Pavel , A.G. Yagües Molina Institut für Physik der Humboldt-Universität zu Berlin, Berlin, Germany S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi University and INFN Bologna, Bologna, Italy e D. Bartsch, I. Brock, S. Goers, H. Hartmann, E. Hilger, H.-P. Jakob, M. Jüngst, O.M. Kind, E. Paul, R. Renner, U. Samson, V. Schönberg, R. Shehzadi, M. Wlasenko Physikalisches Institut der Universität Bonn, Bonn, Germany b N.H. Brook, G.P. Heath, J.D. Morris, T. Namsoo H.H. Wills Physics Laboratory, University of Bristol, Bristol, United Kingdom m M. Capua, S. Fazio, A. Mastroberardino, M. Schioppa, G. Susinno, E. Tassi Calabria University, Physics Department and INFN, Cosenza, Italy e J.Y. Kim, K.J. Ma Chonnam National University, Kwangju, South Korea g Z.A. Ibrahim, B. Kamaluddin, W.A.T. Wan Abdullah Jabatan Fizik, Universiti Malaya, 50603 Kuala Lumpur, Malaysia r Y. Ning, Z. Ren, F. Sciulli Nevis Laboratories, Columbia University, Irvington on Hudson, New York 10027 o J. Chwastowski, A. Eskreys, J. Figiel, A. Galas, M. Gil, K. Olkiewicz, P. Stopa, L. Zawiejski The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow, Poland i L. Adamczyk, T. Bo ld, I. Grabowska-Bo ld, D. Kisielewska, J. Lukasik, M. Przybycień, L. Suszycki Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Cracow, Poland p A. Kotański, W. S lomiński Department of Physics, Jagellonian University, Cracow, Poland

The production of D-*+/-: (2010) mesons in e(+/-) p scattering in the range of exchanged photon virtuality 0.05 < Q(2) < 0.7 GeV2 has been measured with the ZEUS detector at HERA using an integrated luminosity of 82 pb(-1). The decay channels D*+ -> D-0 pi(+) with D-0 -> K-pi(+) and corresponding antiparticle decay were used to identify D* mesons and the ZEUS beampipe calorimeter was used to identify the scattered electron. Differential D* cross sections as functions of Q(2), inelasticity, y, transverse momentum of the D* meson, p(T)(D*), and pseudorapidity of the D* meson, eta(D*), have been measured in the kinematic region 0.02 < y < 0.85, 1.5 < p(T)(D*) < 9.0 GeV and \eta(D*)\< 1.5. The measured differential cross sections are in agreement with two different NLO QCD calculations. The cross sections are also compared to previous ZEUS measurements in the photoproduction and DIS regimes. (c) 2007 Elsevier B.V. All rights reserved.

Received 5 September 2006DOI:https://doi.org/10.1103/PhysRevD.74.059906©2006 American Physical Society

Differential inclusive jet cross sections in neutral current deep inelastic ep scattering have been measured with the ZEUS detector. Three phase-space regions have been selected in order to study parton dynamics where the effects of BFKL evolution might be present. The measurements have been compared to the predictions of leading-logarithm parton shower Monte Carlo models and fixed-order perturbative QCD calculations. In the forward region, QCD calculations at order alpha_s^1 underestimate the data up to an order of magnitude at low x. An improved description of the data in this region is obtained by including QCD corrections at order alpha_s^2, which account for the lowest-order t-channel gluon-exchange diagrams, highlighting the importance of such terms in parton dynamics at low x.

Energetic neutrons produced in ep collisions at HERA have been studied with the ZEUS detector in the photoproduction regime at a mean photon-proton center-of-mass energy of 220 GeV. The neutrons carry a large fraction 0.64 < x(L) < 0.925 of the incoming proton energy, and the four-momentum transfer squared at the proton-neutron vertex is small, vertical bar t vertical bar < 0.425 GeV(2). The x(L) distribution of the neutrons is measured in bins of t. The (1 - x(L)) distributions in the t bins studied satisfy a power law dN/dx(L) proportional to (1 - x(L))(a(t)), with the powers a(t) following a linear function of t: a(t) = 0.88 +/- 0.09(stat.)(-0.39)(+0.34) (syst.) - (2.81 +/- 0.42(stat.)(-0.62)(+1.13) (syst.) GeV(-2))t. This result is consistent with the expectations of pion-exchange models, in which the incoming proton fluctuates to a neutron-pion state, and the electron interacts with the pion. (c) 2005 Elsevier B.V. All rights reserved.

Inclusive Λ, Λ and Ks0 production in deep inelastic ep scattering has been studied with the ZEUS detector at HERA using an integrated luminosity of 120pb−1. Differential cross sections, baryon to antibaryon production asymmetry and baryon to meson production ratios have been measured in the laboratory system for Q2 > 25GeV2.