Study of the market for organic vegetables

This project was led and conducted by HDRA, in collaboration with the Soil Association, Elm Farm Research Centre and The Institute of Rural Studies, Aberystwyth. Data was collected from UK packers and wholesalers of organic vegetables on the amounts, value and source of organic vegetables traded during the 2001/02 season. This was supplemented with crop area data from the organic certification bodies on the area of organic vegetable crops grown in the season. All data was cross-referenced with other published sources of information for the same season. Results and conclusions For a range of twenty-five organic vegetables, which can be grown commercially in the UK, levels of self-sufficiency, or market share, have risen from previous reported levels of 30-40% to an average of 57% for all vegetables. When considered on a crop by crop basis, however, there are large variations of UK market share, ranging from 96% for swedes to 33% for onions. For staple crops such as potatoes, carrots and cabbage the UK share is 65%. Within the main marketing season, for most staple crops, it is estimated that the UK is self sufficient for two-thirds of organic produce with the remainder being imported. Levels of imports rise during the time when UK produce is not in season. Packers and wholesalers estimate that on average there is potential to increase UK market share by 10-15%, although again there are variations on a crop by crop basis. If this were achieved this would put organic production at similar UK market share levels to that achieved in conventional production, namely 70%, which is the target set by the English government’s organic action plan. In order to increase supplies UK growers will have to compete with imports on quality, continuity of supply and in some cases on price. Much of the challenge for UK growers is to increase production at the beginning and end of the season, a time when there is greatest risk from pest, diseases, poor nutrient supply and variable economic returns. The need for organic growers to use organic seed, for which supplies are not always available, could in the short-term act as a constraint to UK growers expanding their production levels. In the EU, the largest markets for organic vegetables are in Germany, France and the UK, these three are major importers of organic vegetables. On the other hand Spain, Italy and the Netherlands are major exporters of organic vegetables. The UK has the lowest level of self-sufficiency in both vegetables and potatoes compared to other EU countries. Many EU countries have increased their levels of production to meet the growing UK market, and for some crops there is oversupply at the EU level. In the future the UK market is predicted to grow at a slower rate, 10-15% per annum. Future growth will be related to a wide range of factors such as the growth of the economy, and education of the consumer to the benefits of organic food. According to retail analysts 8% of the ‘committed’ organic shoppers buy 60% of the organic food. It is a challenge, firstly to encourage the committed consumers to buy more organic food and secondly to entice the other 71% of so called ‘dabblers’, who only currently buy organic food occasionally, to buy more regularly. Commitment to buying organic grows as consumers become more aware of the benefits of organic farming. Recommendations Farmers, policy-makers and other market actors must react swiftly to the changing conditions of the new environment that will evolve in coming years. But in order to do this, government must continue to give clear policy support to the sector. Growers and marketers need a clear picture of the market and knowledge about the supply levels of crops at different times of the year and precisely where there are opportunities for innovation, processing and expanding production. Hence there is an imperative for market information to be collected annually, so future projections could be more easily and accurately mapped. However conversion period time lags will inevitably act to slow the response of farmers to changes in market conditions or consumer behaviour. Growers should also be encouraged to innovate and differentiate their produce, to invest in suitable facilities for storage and processing of crops, such as washing carrots, and to increase their marketing awareness and marketing skills. Co-operation and communication must be fostered within the supply chain. Ideally the food chain should be short, fast, transparent, seamless and collaborative, with all partners in the chain taking equal responsibilities and sharing risks, too often the food chain is complex, price driven, confrontational, disjointed and opaque. An increased UK supply can only be successful if organic market actors join forces to realise the potential of the advantages arising from the economies of scale associated with growing supply. The easiest way to secure long-term growth in UK production is through long-term contracts between partners in the supply chain

Regime Change Behaviour During Asian Monsoon Onset

This is the final version of the article. Available from American Meteorological Society via the DOI in this record.As the ITCZ moves off the equator on an aquaplanet, the Hadley circulation transitions from an equinoctial regime with two near symmetric, significantly eddy-driven cells, to a monsoon-like regime with a strong, thermally direct cross-equatorial cell, intense low-latitude precipitation, and a weak summer hemisphere cell. Dynamical feedbacks appear to accelerate the transition. This study investigates the relevance of this behavior to monsoon onset by using primitive-equation model simulations ranging from aquaplanets to more realistic configurations with Earth’s continents and topography. A change in the relationship between ITCZ latitude and overturning strength is identified once the ITCZ moves poleward of about ∼ 7 ◦ . Monsoon onset is associated with off-equatorial ascent, in regions of non-negligible planetary vorticity, and this is found to generate a vortex stretching tendency that reduces upper level absolute vorticity. In an aquaplanet, this causes a transition to the cross-equatorial, thermally direct regime, intensifying the overturning circulation. Analysis of the zonal momentum budget suggests a stationary wave, driven by topography and land-sea contrast, can trigger a similar transition in the more realistic model configuration, with the wave extending the ascent region of the Southern Hemisphere Hadley cell northward, and enhanced overturning then developing to the south. These two elements of the circulation resemble the East and South Asian monsoons.The work was supported by the UK-China Research & Innovation Partnership Fund, through the Met Office Climate Science for Service Partnership (CSSP) China, as part of the Newton Fund. GKV also acknowledges support from the Royal Society (Wolfson Foundation), the Leverhulme Trust, and NERC

On the spatial and temporal variability of atmospheric heat transport in a hierarchy of models

This is the final version of the article. Available from American Meteorological Society via the DOI in this record.The aquaplanet and heton model data are available upon request to the authors. The wavelet analysis was performed using code from C. Torrence and G. Compo, available at http://atoc.colorado.edu/research/wavelets/.The present study analyzes the spatial and temporal variability of zonally integrated meridional atmospheric heat transport due to transient eddies in a hierarchy of datasets. These include a highly idealized two-layer model seeded with point geostrophic vortices, an intermediate complexity GCM, and the European Centre for Medium-Range Weather Forecasts interim reanalysis (ERA-Interim) data. The domain of interest is the extratropics. Both the two-layer model and the GCM display a pronounced temporal variability in the zonally integrated meridional transport, with the largest values (or pulses) of zonally integrated transport being associated with extended regions of anomalously strong local heat transport. In the two-layer model these large-scale coherent transport regions, termed "heat transport bands," are linked to densely packed baroclinic vortex pairs and can be diagnosed as low-wavenumber streamfunction anomalies. In the GCM they are associated with both the warm and cold sectors of midlatitude weather systems. Both these features are also found in ERA-Interim: the heat transport bands match weather systems and occur primarily in the storm-track regions, which in turn correspond to planetary-scale climatological streamfunction anomalies. The authors hypothesize that the temporal variability of the zonally integrated heat transport is partly linked to oscillatory variations in the storm-track activity but also contains a background red noise component. The existence of a pronounced variability in the zonally integrated meridional heat transport can have important consequences for the interplay between midlatitude dynamics and the energy balance of the high latitudes.During this research, G. Messori has been funded by the U.K.’s Natural Environment Research Council (RAPID–RAPIT project), Sweden’s Vetenskapsrådet (MILEX project; Grant 2012-40395-98427-17), and the Department of Meteorology of Stockholm Universit

Processes and Timescales in Onset and Withdrawal of 'Aquaplanet Monsoons'

This is the final version. Available from American Meteorological Society via the DOI in this record.Data availability: The research materials supporting this publication can be accessed by contacting Ruth Geen ([email protected]).Aquaplanets with low heat capacity slab ocean boundary conditions can exhibit rapid changes in the regime of the overturning circulation over the seasonal cycle, which have been connected to the onset of Earth’s monsoons. In spring, as the ITCZ migrates off the Equator, it jumps poleward and a sudden transition occurs from an eddy-driven, equinoctial regime with two weak Hadley cells, to a near angular momentum conserving, solstitial regime with a strong, cross-equatorial winter hemisphere cell. Here, the controls on the transition latitude and rate are explored in idealised moist aquaplanet simulations. It is found that the transition remains rapid relative to the solar forcing when year length and slab ocean heat capacity are varied, and, at Earth’s rotation rate, always occurs when the ITCZ reaches approximately 7°. This transition latitude is, however, found to scale inversely with rotation rate. Interestingly, the transition rate varies non-monotonically with rotation, with a maximum at Earth’s rotation rate, suggesting that Earth may be particularly disposed to a fast monsoon onset. The fast transition relates to feedbacks in both the atmosphere and the slab ocean. In particular, an evaporative feedback between the lower-level branch of the overturning circulation and the surface temperature is identified. This accelerates monsoon onset and slows withdrawal. Lastly, comparing eddy-permitting and axisymmetric experiments shows that, in contrast with results from dry models, in this fully moist model the presence of eddies slows the migration of the ITCZ between hemispheres.UK-China Research and Innovation Partnership FundRoyal SocietyLeverhulme Trus

The effects of increasing humidity on heat transport by extratropical waves

This is the final version of the article. Available from AGU via the DOI in this record.The data for the simulations discussed are available from the authors on request. The radiation scheme used is described in supporting information Text S1.This study emphasizes the separate contributions of the warm and cold sectors of extratropical cyclones to poleward heat transport. Aquaplanet simulations are performed with an intermediate complexity climate model in which the response of the atmosphere to a range of values of saturation vapor pressure is assessed. These simulations reveal stronger poleward transport of latent heat in the warm sector as saturation vapor pressure is increased and an unexpected increase in poleward sensible heat transport in the cold sector. The latter results nearly equally from changes in the background stability of the atmosphere at low levels and changes in the temporal correlation between wind and temperature fields throughout the troposphere. Increased stability at low level reduces the likelihood that movement of cooler air over warmer water results in an absolutely unstable temperature profile, leading to less asymmetric damping of temperature and meridional velocity anomalies in cold and warm sectors.Ruth Geen was funded by the Grantham Institute. Additional funds for mobility and consumables were provided by Climate‐KIC

Forecasting South China Sea Monsoon Onset Using Insight From Theory

This is the final version. Available on open access from Wiley via the DOI in this recordData Availability Statement: Data sets for this research are available in these in-text data citation references: Japan Meteorological Agency/Japan (2013); Japan Meteorological Agency (Ongoing); ECMWF (2016).Monsoon onset over the South China Sea occurs in April–May, marking the start of the wet season over East Asia. Skillful prediction of onset timing remains an open challenge. Recently, theoretical studies using idealized models have revealed feedbacks at work during the seasonal transitions of the Hadley cells and have shown that these are relevant to monsoon onset over Asia. Here, I hypothesize that monsoon onset occurs earlier in years when the atmosphere over the South China Sea is already in a state where these feedbacks are more easily triggered. I find that local anomalies in lower‐level moist static energy in the preceding January–March are well correlated with South China Sea Monsoon onset timing. This relationship remains relatively consistent on decadal timescales, while correlations with other teleconnections vary, and is used to develop a simple forecast model for onset timing that shows skill competitive with that of more complex models.Newton Fun

The energy and dynamics of trapped radiative feedback with stellar winds

In this paper, we explore the significant, non-linear impact that stellar winds have on H II regions. We perform a parameter study using three-dimensional radiative magnetohydrodynamic simulations of wind and ultraviolet radiation feedback from a 35 M⊙ star formed self-consistently in a turbulent, self-gravitating cloud, similar to the Orion Nebula (M42) and its main ionizing source θ1 Ori C. Stellar winds suppress early radiative feedback by trapping ionizing radiation in the shell around the wind bubble. Rapid breakouts of warm photoionized gas (‘champagne flows’) still occur if the star forms close to the edge of the cloud. The impact of wind bubbles can be enhanced if we detect and remove numerical overcooling caused by shocks crossing grid cells. However, the majority of the energy in the wind bubble is still lost to turbulent mixing between the wind bubble and the gas around it. These results begin to converge if the spatial resolution at the wind bubble interface is increased by refining the grid on pressure gradients. Wind bubbles form a thin chimney close to the star, which then expands outwards as an extended plume once the wind bubble breaks out of the dense core the star formed in, allowing them to expand faster than a spherical wind bubble. We also find wind bubbles mixing completely with the photoionized gas when the H II region breaks out of the cloud as a champagne flow, a process we term ‘hot champagne’

Scalable design of tailored soft pulses for coherent control

We present a scalable scheme to design optimized soft pulses and pulse sequences for coherent control of interacting quantum many-body systems. The scheme is based on the cluster expansion and the time dependent perturbation theory implemented numerically. This approach offers a dramatic advantage in numerical efficiency, and it is also more convenient than the commonly used Magnus expansion, especially when dealing with higher order terms. We illustrate the scheme by designing 2nd-order pi-pulses and a 6th-order 8-pulse refocusing sequence for a chain of qubits with nearest-neighbor couplings. We also discuss the performance of soft-pulse refocusing sequences in suppressing decoherence due to low-frequency environment.Comment: 4 pages, 2 tables. (modified first table, references added, minor text changes

Impact of local recharge on arsenic concentrations in shallow aquifers inferred from the electromagnetic conductivity of soils in Araihazar, Bangladesh

The high-degree of spatial variability of dissolved As levels in shallow aquifers of the Bengal Basin has been well documented but the underlying mechanisms remain poorly understood. We compare here As concentrations measured in groundwater pumped from 4700 wells <22 m (75 ft) deep across a 25 km2 area of Bangladesh with variations in the nature of surface soils inferred from 18,500 measurements of frequency domain electromagnetic induction. A set of 14 hand auger cores recovered from the same area indicate that a combination of grain size and the conductivity of soil water dominate the electromagnetic signal. The relationship between pairs of individual EM conductivity and dissolved As measurements within a distance of 50 m is significant but highly scattered (r2 = 0.12; n = 614). Concentrations of As tend to be lower in shallow aquifers underlying sandy soils and higher below finer-grained and high conductivity soils. Variations in EM conductivity account for nearly half the variance of the rate of increase of As concentration with depth, however, when the data are averaged over a distance of 50 m (r2 = 0.50; n = 145). The association is interpreted as an indication that groundwater recharge through permeable sandy soils prevents As concentrations from rising in shallow reducing groundwater