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More than 64% of Namibia's land is occupied by the savanna ecosystems which are vulnerable to climate change and variability. These ecosystems partly consist of forest ecosystem patches which are prime sources of many livelihoods in the country. The effects of climate change are likely to drive the majority of the country's population to poverty if these resources are not sustainably managed. Therefore an understanding of forest dynamics and their responses to climate is important. Dendrochronology is a study that provides time-series data of climate change and variability, and the responses of trees to such changes. The data are used to reconstruct past events of climate and also to forecast possibilities. Dendrochronological studies have been carried out in Namibia, however, a review of such studies is lacking. This study thus aimed at closing this gap and carried out a literature review on the dendrochronological studies in Namibia. The review showed that the field of dendrochronology is relatively new and has been less applied in Namibia. There is a need for further dendrochronological studies in order to understand how the country can adapt better under the current and forecasted climate regimes. A focus on the marginal forests, encroachers and trees that are of indigenous use, is recommended. In cases of the absence of clear ring formation, which might be the case in arid to hyper arid, the use of staple isotopes is recommended.

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The global loss of biodiversity has led to relentless calls from conservationists to protect the environment and natural habitats. The objective of this study was to determine the effectiveness of crown diameter for prediction of canopy cover under national park conditions. The study was conducted in Etosha National Park, Namibia in 2015. Three tree species, namely Combretum imberbe, Colophospermum mopane and Terminalia prunioides were considered as representative members of the park species based on their relative population density. The study employed regression analysis to examine the nature of relationships between tree crown diameter (the dependent variable) and tree height, diameter at breast height (DBH) and distance from watering holes as independent variables. The regression coefficients for Combretum imberbe were not significant (P = 0.116; P = 0.431; P = 0.884, respectively), suggesting that crown diameter was not well estimated by these explanatory variables. On the other hand, there were significant relationships between DBH and crown diameter, as well as between crown diameter and tree height. Tree height emerged as the stronger predictor of crown diameter for both Terminalia prunioides and Colophospermum mopane. Therefore, the relationship between tree height and crown diameter as explained by cubic function can further be used to evaluate and estimate canopy cover under national park conditions.

Global Circulation Models (GCMs) are used to forecast climate change in Southern Africa, and the evidence shows that the region is going to warm up by up to 2° by the year 2050. Namibia is one of the driest countries in Southern Africa and is at a high risk of becoming much drier than current situation by 57%. Very few studies have been carried out in Southern Africa to show actual impacts of climate change. Practical applicability of GCMs at a local spatial scale remains limited due to the coarse nature of the models. Hence, improvement of the GCMs must begin with better understanding of the local microclimates and how they respond to regional circulation patterns. In many regions of Southern Africa, the lack of potential tools to access old climatic records precludes the estimation of climate trends beyond 100 years. In spite of these impediments, there are areas with excellent tree species such as Dichrostachys cinerea that are able to be used as climatic archives for specific time periods. In this chapter, the study shows that the combination of tree ring chronologies and precipitation records is a powerful methodology in climate modeling in the southern hemisphere and reveals nuances that show climate change. The evaluation of data from tree rings coupled with precipitation trends reveals signals that show that climate has indeed been changing over the past ten decades and will have a negative impact on livelihoods. These data can now be used in predictive models that can be used to project future scenarios and assist policy makers and planners to see how climate will evolve in the next 50–60 years.