Browsing by Subject "Weather"

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    The formulation of a classification procedure for specific use on cumulus cloud weather modification experiments
    (1980) Erasmus, David Andre; Keen, Cecil
    The central theme of this study concerns the use of classification schemes on weather modification experiments designed to investigate the possibility of increasing rainfall from individual cumuli or cumulus cloud systems. The principal objectives of these experiments are the evaluation of treatment effects and the identification of situations where seeding with artificial ice-nuclei is likely to have positive results. The classification of experimental units into categories that are associated with significantly different physical processes aids the evaluation process and the formulation of seeding strategies in the desired manner. As part of this study a classification scheme, which stratifies convective events on the basis of the synoptic situations which give rise to and maintain the convection, is formulated. In chapter seven and eight this scheme and another scheme presently being employed on a cumulus cloud weather modification experiment are examined statistically. Investigations show that the formulated scheme attains the objectives of classification to a greater degree. Certain attributes of the second scheme, permit the development of a classification procedure whereby the most effective stratification of experimental units can be accomplished.
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    Navigating extreme weather events: An anthropological investigation
    (2025) Perin, Ridah; Morreira, Shannon
    The aim of this study was to investigate how do people respond to extreme weather events (EWEs), paying special attention to heavy rainfall. The data and literature gathered unearths strategies and tactics embedded in the social structure of the area of Crawford. These strategies and tactics are either manipulated or reconfigured in patterns of individuality, to gauge what necessary actions are required to mitigate the impacts of heavy rainfall. These approaches were used to answer the foundational question of this study, what roles do existing social relationships play in people's perceptions and responses to extreme weather events? By utilising qualitative research techniques, this study argues that residents of a middle-income neighbourhoods like Crawford respond, adapt and prepare for extreme rainfall in individualised manners. Contrary to areas of less socioeconomic standing who utilise communal strategies such as conviviality to address the challenges heavy rainfall brings.
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    Open Access
    The effect of weather on critic ratings and auction prices for Stellenbosch Bordeaux blends from 2001-2021.
    (2025) Everts, Charl Jan; Conradie, Beatrice
    Growing season conditions are crucial in determining the quality of grapes in a vineyard. Identifying the climate variables with the greatest effect is therefore of interest to viticulturists and winemakers. Continued warming is evident for Stellenbosch since 2001, especially the last ten years. This study models the effect of temperature and rainfall variables on wine quality, represented by wine ratings and auction prices for Stellenbosch Bordeaux-style red wines. Findings indicate that, in terms of the relationship between weather and wine quality, Stellenbosch aligns more closely with Australia than Bordeaux. Growing season temperatures and harvest rainfall play a significant role in determining the outcome of a vintage. An optimal growing season temperature is estimated at 20.5°C. A climate-based vintage heuristic suggests that vintages with growing season temperatures near 20.5°C and January-February rainfall below 60mm are more likely to be exceptional. The heuristic suggests that the 2008 and 2011 vintages are undervalued, and a great 2024 vintage is to be expected. Rating inflation is evident for the portfolio of wines assessed. Similarly, inflation-adjusted auction prices for these wines have increased more than 5% annually. This price growth represents real value appreciation, suggesting that rating inflation may be attributed to objectively better wines. Proven adaptation strategies will be critical as warming and rainfall variability intensify. The increase in ratings and auction prices may already reflect successful farmer adaptation. While Stellenbosch winemakers have demonstrated resilience, increasing water scarcity may elevate the importance of winter rainfall effects, mirroring trends seen in Bordeaux.