UK report says Africa lacks "political will to invest in the collection" of needed data.
July 2008, "
Rainfall and Water Resources Variability in Sub-Saharan Africa during the 20th Century," Tyndall Centre for Climate Change Research, University of East Anglia, UK
Abstract, p. 1, "
No consistent signals in rainfall and river flows emerge across the whole of SSA.p. 4, "
Detailed information on CRU TS 2.1 quality control and notes on data interpretation can be found in relevant publications, but we note here that Africa has generally poor spatial and temporal coverage
(Hulme, 1996; Nicholson, 1996) and this is true for the CRU TS 2.1 data, particularly before the 1930s and after about 1980. To explore the possible effects of changing station distribution on basin rainfall series and runoff relationships we use gridded time series of the number of stations within range of a grid box (Mitchell and Jones, 2005; www.cru.uea.ac.uk/~timm/grid/stns.html) and calculate a basin average series from all grid boxes in the basin. ...Because these series do not record the actual number of stations that have been used to generate rainfall values we concentrate on changes in their
- relative rather than their absolute number."...
p.6, (end) "Finally, the Horn of Africa, Ethiopia and Somalia, are poorly represented because of limited data availability, especially in eastern and southern Ethiopia where some very large river basins (e.g. Omo, Wabe Shebelle)
- remain sparsely instrumented and under-studied."...
p.8, (end), "Unfortunately it has not been possible to update most of these series beyond 2002, however, recent studies by L’Hôte et al. (2002) and Dai et al. (2004) note that rainfall conditions in the Sahel have not returned to those prior to the early 1970s. Rainfall and river flows certainly reached their lowest point in the mid-1980s and have stabilised and in most cases recovered somewhat."...- (More on lack of rainfall stations in Africa sufficient to charge the US with genocide and requirement to pay billions in 'reparations' to corrupt governments. ed.)
page 19, "Figure 10...
Correlations tend to strengthen moderately from the 1920s to the 1950s (as station density rises) and most records show a rapid (step-like) decay roughly around 1980 at which point data from the 1990s would just begin to feed into the relationships as data from 1970 are removed. This behaviour most likely reflects the dramatic decline in rainfall stations after 1990, with numbers in most cases dropping from over 50 to
- less than 10
- between the late 1980s and early 1990s."...
page 20, "
The time series of rainfall stations in Central Africa (Figure 9 Congo and Bangui) shows their extreme scarcity for this region during most of last century. The Congo shows a rainfall breakpoint in 1980 (1981 river flows) that is associated with a modest difference in the slope and marked reduction in the strength of the rainfall-runoff relationship. The running correlation is highly unstable until 1940 because no rainfall stations contributed to the basin until 1930; and from then on,
page 21, Discussion, "
The decline in the overall number of sites, their frequency of reporting and in some cases quality of measurements, are major concerns for the understanding of environmental change in SSA. Although this is part of a global phenomenon with hydrological data (Vörösmarty et al., 2001), the situation is particularly bad in SSA. The massive decline in rainfall stations used in CRU TS 2.1 from the 1980s onwards
- severely constrains efforts to accurately monitor climate variability and confidently model biophysical systems.
This is part of Africa’s wider financial, political and institutional challenges to climate research (Washington et al., 2006).
Halting this trend will not be straightforward, current efforts to re-engage African governments and donors through demonstrating the practical and economic value of such measurements (e.g. CLIMDEV) may founder due to
- lack of widespread support.
These calls follow on from many previous attempts to support and develop observations in Africa (Hydromet, 1982; World Bank, 1989, HYCOS and so on). Without political will to invest in the collection of such data and with the reluctance of donors to support recurrent costs indefinitely, a strategic and pragmatic approach is called for. This should be based on identifying a limited set of benchmark sites for long-term international support because of their significance for understanding global environmental change. To overcome some of the limitations of in situdata compilation, it would be useful to overlap and extend our river basin rainfall series using merged/ full satellite products. (page 21)...
page 22, "Future Climate Change"
"As already noted it may be some time before climate change signals can be reliably identified in African river flow series. Although we note that the floods in summer 2007 across SSA are unprecedented in their temporal and spatial scale since at least the end of the 19th century....Most projections of future climate and impacts on runoff when averaged across multiple climate models suggest relatively modest changes out to the 2050s vis-à-vis the variability observed during the 20th century."...--------------------------
Even the UN notes
crime and poor government in Africa increases likelihood of drought and other negative consequences.
"
"Human activities such as
deforestation and inappropriate management of land and water resources can contribute to the frequency and impacts of natural climatic events. For example,
clearing of tropical forests in Central and Western Africa alters local climate and rainfall patterns and increases the risk of drought. Clearing of vegetation increases run-off and soil erosion, and damming of rivers and draining of wetlands reduces the environment's natural ability to absorb excess water,
increasing the impacts of floods."...
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