Large-scale growers need to supply large volumes of consistent high quality produce for consumers. To optimise their production they use weather data, and crop models to predict crop performance and irrigation scheduling. Limited or no access to accurate weather forecasts beyond 10 to 14 days result in supply-demand imbalances linked to food waste and overproduction linked to higher greenhouse gas emissions.
Field vegetables and salad productivity is intrinsically linked to rainfall, which impacts the supply and availability on our supermarket shelves. Since growers need better control over their water use, they choose to be based in the south and eastern regions that are dependent on summer irrigation. The expansion of the horticultural industry combined with climate change makes irrigation management and scheduling increasingly challenging to feed a growing population.
The UKSRI project has focussed on the vulnerabilities in the food system from mismatches between supply and demand for one of the UK’s largest salad growers. It has piloted the UK’s first reliable summer rainfall insights to inform decisions to mitigate potential crop losses and reduce food waste. Phase II will now see the development and automation of this service for wider delivery for UK growers and producers. Its impact will be an improvement in land-use efficiency, competitiveness for the horticultural industry, lower dependency on fresh produce imports and reductions in food waste in the field and the UK’s contribution to climate change.
Users and their needs
UKSRI service requirements were discussed with growers to improve the optimisation of their fresh produce supply (and demand) modelling in the UK. Our main user was the main European supplier of iceberg lettuces to supermarkets, and another grower supplying Nandos and the main supermarkets with courgettes and sweetcorn. UKSRI also explored the service potential for the potato industry through an intensive NIAB irrigation training workshop. The project team identified several challenges and explored the commercial and technical risks in the development of its proposed summer rainfall prediction service.
Growers need more accurate daily weather data at the field-level, and at seasonal timescales, since the main risk (B2B relationships, food waste, logistical / foreign import dependencies) results from not meeting buyer (grocery) quality or volumes for pre-arranged contracts. Supply shortfalls or surpluses can be mitigated in advance with all-year-round access to more accurate and reliable long-term weather data that must include:
- Daily-type insights
- Confidence estimates
- Weekly update frequency
- Field-level weather
Our long-term forecasts have now been demonstrated through a successful pilot for two key forecast variables (rainfall and temperature). The agricultural service concept and a technical demonstration of the summer rainfall prediction system were presented at an international drought conference hosted by Oxford University and at the UK-Taiwan business cooperation fair from March to April 2019.
Verification work is in progress using HPC facilities at the STFC Hartree Centre, due for completion in July 2019. This will see the delivery of a field-level assessment of temperature and rainfall forecast accuracy and reliability, an essential buying criterion for our key stakeholder.
Service/ system concept
Growers will be delivered with a fortnightly / monthly report updating them on the 2 to 15 week seasonal weather variability at the field-level. This data will be combined with reliability estimates (a forecast range) and access to historical forecast performance data to enable them to make cost-benefit / evidence-based decisions and confidently adjust crop decisions to optimise their production to meet quality standards and to meet grocery supply programmes.
The service will empower growers to make better-informed decisions on how to best adjust their crop propagation or sowing, ensuring an all-year-round supply less dependent on imports during volatile periods of weather. Other decisions such as site selection would enable growers to better match their cropping to soil texture / moisture availability and to select more suitable crop mixes, improve disease alert systems and develop more effective advisory services for preventative spraying. The outcome of our service would reduce greenhouse gas contributions from the UK agriculture sector and increase its resilience weather extremes linked to fresh produce supply shortages for supermarket shelves.
Space Added Value
Our summer rainfall system mainly exploits ECMWF Re-Analyses data (ERA-40, ERA-interim and ERA-5) and EC Copernicus Climate Change Service (C3S) seasonal forecast model data. ERA-5 data assimilation combines land-based observations with measurements from weather satellites (MeteoSat geosynchronous imagery / MetOp polar orbiting meteorological satellites forming part of the EUMETSAT Polar System (EPS). These are then subject to 4D-Var data assimilation pre-acquisition, providing initial conditions for seasonal climate forecast models. Weather Logistics’ algorithm automates the download and processing of this satellite derived data from the EC Copernicus / the Climate Data Store using ECMWF’s CDS Toolbox.
Weather Logistics’ uses numerical weather prediction (NWP) data from multiple European weather centres that include the European Center for Medium-range Weather Forecasts (ECMWF), the UK Meteorological Office and Météo-France. European weather centres use of about 20% of available satellite measurements for operational weather prediction.
UKSRI has demonstrated that the combination of these NWP outputs with Weather Logistics’ empirical forecast system, especially its unique Atlantic jet stream technique, improves the accuracy of UK seasonal rainfall prediction by up to 270%.
The ESA Kick Start activity was successfully concluded in May 2019. Weather Logistics presented its summer rainfall system at the Drought and Water Scarcity International Conference, Oxford University. An expression of interest was later signed with a global salad grower to proceed with Phase II development. This co-funded project will be implemented in partnership with a global business process and IT outsourcing firm. It will involve a forecast trial period over the next 6 to 12 months, with active stakeholder engagement, followed by commercial services by Q1 2020.