Hydro-climatic trends and water resource management implications based on multi-scale data for the Lake Victoria region, Kenya

Abstract

Unreliable rainfall may be a main cause of poverty in rural areas, such as the Kisumu district by Lake Victoria in Kenya. Climate change may further increase the negative effects of rainfall uncertainty. These effects could be mitigated to some extent through improved and adaptive water resource management and planning, which relies on our interpretations and projections of the coupled hydro-climatic system behaviour and its development trends. In order to identify and quantify the main differences and consistencies among such hydro-climatic assessments, this study investigates trends and exemplifies their use for important water management decisions for the Lake Victoria drainage basin (LVDB), based on local scale data for the Orongo village in the Kisumu district, and regional scale data for the whole LVDB. Results show low correlation between locally and regionally observed hydro-climatic trends, and large differences, which in turn affects assessments of important water resource management parameters. However, both data scales converge in indicating that observed local and regional hydrological discharge trends are primarily driven by local and regional water use and land use changes.

Influences of shifts in climate, landscape, and permafrost on terrestrial hydrology

“…Nonintuitive R responses to P change have been found in different studies of hydroclimatic change, for catchments of different scales and in different parts of the world. Reported earlier findings include R change in the opposite direction than P due to concurrent natural or anthropogenic ET changes [ Shibuo et al , 2007], in the same direction but considerably more than P due to concurrent water storage changes, e.g., in the terrestrial cryosphere [ Bring and Destouni , 2011], or entirely unrelated to P change due to various parallel land and water use changes on different unresolved local regional scales [ Koutsouris et al , 2010]. Hence, linear assumptions of a projected P increase (decrease) leading directly to correspondingly wetter (drier) landscape conditions may in many cases be too simplistic.…”

Comparing global precipitation data sets in eastern Africa: a case study of Kilombero Valley, Tanzania

“…This is primarily because the choice of input data has a large impact on decision making in important areas such as water management and planning (Koutsouris et al, 2010). For these reasons, many studies exist whereby gridded precipitation data are evaluated against gauge data (e.g.…”

Quantifying hydrological responses of small Mediterranean catchments under climate change projections

“…While these projections can provide useful information for developing and supporting climatic change impacts adaptation and mitigation plans at regional level, they are not quantitatively and qualitatively sufficient for supporting practical water resources management at the catchment scale. Projected trends and magnitudes of change based on regional projections can significantly differ at the catchment scale (Pielke et al, 2002;Koutsouris et al, 2010). Indeed, as moving from regional to catchment scale the heterogeneity and natural variability in both climatic and hydrological processes increase making the assessment of hydrological impacts of climatic change more complex and uncertain.…”