An Interview with Dr. Olivier Crespo

All farmers, everywhere, face uncertainty as a result of seasonal weather variations. Successful farmers know how to cope and make decisions for selecting the best farming practices for the current season’s weather conditions. However, in recent years, decision-making has become more difficult because of the increasing frequency of extreme weather patterns that deviate from “normal” seasonal fluctuations.

Dr. Olivier Crespo

Recently, START staff members interviewed Dr. Olivier Crespo, the Principal Investigator (PI) of the 2011 START Grant for Global Environmental Change Research titled Improving Seasonal Forecast Information for Managing On-farm Decisions. In the proposal submitted to START by the collaborative team of Dr. Olivier Crespo, Dr. Mark Tadross, Dr. Peter Johnston and Professor Sue Walker included the following statement of intent: “We are seeking new ways of making the dissemination of the forecasts easier and more understandable. Our experience within the agricultural sector has highlighted the value of graduating from simple seasonal forecasts to include information on agricultural impacts and management options.”

Engaging with local farmers who have limited access to irrigation

This project is designed to help farmers make decisions for this season’s crops based on information from advanced crop models that were developed at Climate Systems Analysis Group at University of Cape Town, South Africa. One model, the APSIM (Agricultural Production System sIMulator ), allows users to improve their understanding of the impact of climate, soil types, and management on crop and pasture production. It is a powerful tool for exploring agronomic adaptations including: changes in planting dates, the selection of the proper crop variety, selections for fertilizer/irrigation management and timing, etc.

1. How is your research progressing? Have there been any interesting successes or challenges for the project thus far?

Since the official launch of the project in June 2011, scientific development has gone smoothly. The first step was to model the case study area in the Swartland (Western Cape, South Africa). This has been done for rain-fed winter wheat, which is the major cropping system in this region. The APSIM crop model now allows us to simulate the wheat outputs when subjected to a unique weather condition.

We are working with farmers to help them use the crop model by using weather data that are consistent with the types of seasonal forecasts provided by the Climate Systems Analysis Group (CSAG) in Cape Town.

At this stage, the major challenge is to define and transform a rather generic description of the next 3-month weather patterns into a detailed data set that will allow the crop model to simulate crop outputs. We are exploring different ways to communicate to farmers with sufficient simplicity to allow them to benefit from the information that has already been developed.

The next step will be to evaluate and improve a crop model for rain-fed maize in the Free State, beginning around New Year 2012.

2. How did your team decide to work together? What parts of this research project most interest you? Why did you decide to do this particular project?

The team of climatologists, agro-meteorologists and crop modelers has been collaborating since 2008. Each person on the team has distinct skills for using weather and seasonal forecasts, as well as a knowledge of the limitations of the models.

I am motivated to develop techniques that provide new perspective on existing or never-tested alternative cropping practices.

Even though scenarios for climate are uncertain, they provide information on projected long-term climate patterns. With an understanding of projected changes, it is possible to make long-term strategic decisions.

Seasonal forecasts, on the other hand, can help farmers to make decisions and improve their farming tactics for the current growing season. But monthly seasonal forecasts do not always provide the accuracy that the farmer needs to make daily and weekly decisions to assure that crop growth is optimal. It is our goal to “pull out” valuable information from seasonal forecasts to help farmers with time-sensitive tactical decision-making.

3. How do you feel your research will contribute to your stakeholders’ abilities to adapt to global environmental change? How will this project be relevant to broader regional and international GEC research?

This project will benefit the local community of stakeholders as follows: 1) The stakeholders will gain experience in using climate forecasts and will develop awareness and understanding of their climatic conditions, and will learn how to use predictions. 2) A major outcome of the project will be to provide the stakeholder community with new approaches and tools to allow them to use the modeling information that has already been developed by CSAG.

Even though we are working at the level of individual farms, the approach is expected to be useful elsewhere in South Africa. The skills learned here can be applied to models that have been developed for other crops. At a larger level, this project will improve knowledge on how to use seasonal forecasts to help improve agricultural practices and increase yields throughout Africa, and worldwide.