Valuation of Climate Services for Viticulturists: Tackling fungal diseases

Viticulturists developing adaptation strategies to mitigate the impact of climate change, which affects a grapevine's physiology and wine typicity, can benefit from climate services. Climate services translate physically based variables, such as temperature and precipitation, into actionable, decision relevant bioclimatic indicators, such as Spring Rain, Heat Stress Days, and Warm Spell Duration. These bioclimatic indicators enable the mitigation of fungal diseases, specifically downy and powdery mildew, as well as sunburn. Accurate seasonal forecasts of these bioclimatic indicators can help farmers with viticulture, labor, and stock management, as well as improve the yield and value of wine-quality grapes. Seasonal forecasts of these indicators are available on the MED-GOLD project's dashboard. This study determines an annual service fee to access these forecasts on the dashboard. The annual fee accounts for the seasonal forecast accuracy over part of the Douro wine region of Portugal, as well as the potential savings and losses of micro (te1 ha) holding grape growers. The revenue generated from this climate service fee exceeds the cost of dashboard maintenance by nearly 10 times, even with a fee which is less than half of the potential savings of the micro holding farmer.