El Nino southern oscillation based rainfall forecasts in southern Africa. 1. seasonal forecasts can help communal farmers manage drought

Drought is the single most important natural disaster affecting some parts of southern Africa virtually every year. Because of the region's heavy dependence on rain-fed agriculture, drought is usually associated with widespread crop failure, livestock deaths, environmental degradation, famine and socio-economic stress. Reliable seasonal rainfall forecasts could lead to proactive drought mitigation strategies. In this study, the utility of probabilistic seasonal forecasts was examined in terms of forecast skill and timeliness for decision making. The Southern Oscillation Index (SOI) in spring was a useful indicator of summer rainfall (Nov-Mar) for c. 50% of stations in southern Africa and of drier than normal conditions for c. 20% of stations. The SOI average would have been useful to forecast severe droughts in parts of southern Africa between 1930 and 1992. The El Nino Southern Oscillation (ENSO) signal was greatest in central South Africa, Zimbabwe, Tanzania and Kenya. Forecast lead-times were 0-2 months, which was considered adequate for decision making by communal farmers - provided the forecasts were relevant and tailored for the local area. The climate analysis package Rainman International with international data is a useful forecasting tool on subcontinental and local scales. Training of agricultural extension officers in the use of climate analysis software like Rainman International is necessary to ensure effective dissemination to, and application of forecasts by, communal farmers

El Nino southern oscillation based rainfall forecasts in southern Africa. II. daily forecasts could help summer planting decisions in Zimbabwe

Analysis of historical data of daily rainfall for Harare showed that El Nino Southern Oscillation (ENSO) impacts on the timing of break-of-dry season and follow-up rainfall as well as the frequency of rain events during summer (Nov-Mar). The Southern Oscillation Index (SOI) was a useful indicator of the timing and frequency of these events, defined as 40mm of rainfall in 3 days. Median dates for the first and second events were 1 December and 17 December respectively; ENSO contributed to a shift in these dates of about 2 weeks. The percent chance of receiving break-of-season rainfall by 1 December during La Nina years was 67% compared to 30% in El Nino years. Maize is a staple food in Zimbabwe and delaying planting after 1 December can result in lower yields. Communal farmers could benefit from this apparent ENSO signal in Zimbabwe by adjusting crop variety, planting time and fertilizer rate. However, poor spatial coverage of long-term (>80 years) daily rainfall data in Zimbabwe limits widespread application

Theoretical framework for applied climate education: 2. Training development and delivery for building knowledge and skills to apply seasonal climate forecasts in agriculture

Workshops were held in Australia, India, Indonesia and Zimbabwe between January 1999 to September 2002 to enhance understanding of climate variability, ENSO and seasonal forecasts, particularly as they impact on agriculture systems in these countries. These workshops were delivered to a range of participants including agriculture department staff, farmers, researchers, bureau of meteorology staff and food security personnel. A range of resource materials were customised in Australia for these other countries and adapted for workshops. During previous visits to these countries, there were meetings with researchers, extension officers, farmers, meteorologists, policy makers and other project members and as a result, a set of workshop aims and criteria for participants attending the workshops was developed. Educational course-ware has been developed for a range of stakeholders including secondary schools, vocational and tertiary education, formal and informal materials for workshops. This material has been developed not only in booklet format but also multimedia format so as to appeal to the changing face of education and learning styles of students. A structured program for workshops were proposed but had to in-build flexibility so as to cope with different needs of participants. The workshops consisted of sessions on the climate of their country, tools to assist forecasting, application of forecasts, communication, evaluation and future work. This is an edited version of the paper presented at the International Conference on Applying seasonal climate forecasts in agriculture, 24-26 September 2002., Tamil Nadu Agricultural University, Tamil Nadu, INDIA