John Sutcliffe

Water balance of Lake Victoria: update to 2000 and climate change modelling to 2100 / Bilan hydrologique du Lac Victoria: mise à jour jusqu’en 2000 et modélisation des impacts du changement climatique jusqu’en 2100

Abstract Abstract An annual water balance model of Lake Victoria is derived for the period 1925–2000. Regression techniques are used to derive annual inputs to the water balance, based on lake rainfall data, measured and derived inflows and estimated evaporation during the historical period. This approach acknowledges that runoff is a nonlinear function of lake rainfall. A longer inflow series is produced here which is representative of the whole inflow to the lake, rather than just from individual tributaries. The results show a good simulation of annual lake levels and outflows and capture the high lake level in 1997–1998. Climate change scenarios, from a recent global climate model experiment, are applied to the lake rainfall inflow series and evaporation data to estimate future water balances of the lake. The scenarios produce a potential fall in lake levels by the 2030s horizon, and a rise by the 2080s horizon. A discussion of the application of climate change data to this complex hydrological system is presented.

A water balance study of the upper White Nile basin flows in the late nineteenth century

Abstract A water balance model of the Nile is described, working in terms of dry season flows. The main use of the modelling studies was to extend flows back to the start of observations at Aswan in 1869, and hence to estimate the levels of Lake Victoria during the high flow event of the 1870s. New estimates of Lake Victoria levels and outflows for the period 1870–1895 are deduced, extending the length of the observed data for Lake Victoria by some 25%. Crucially, the analysis includes the major flood event of 1878, which historical evidence suggests was the highest since 1860 or earlier. The modelling results are compared with previous estimates and a detailed examination of historical evidence. Some prospects for future levels are considered, taking into account the reconstructed levels of the late nineteenth century.

Ancient Irrigation and Buddhist History in Central India: Optically Stimulated Luminescence Dates and Pollen Sequences from the Sanchi Dams

This paper presents the results of a recent pilot project aimed at obtaining optically stimulated luminescence (OSL) dates from a group of ancient irrigation dams in central India. The dams are all situated within an area of 750 km2 around the wellknown Buddhist site of Sanchi, the latter established in c. third century B.C. and having a continuous constructional sequence up to the twelfth century A.D. They were documented during earlier seasons of the Sanchi Survey, initiated in 1998 in order to relate the site to its wider archaeological landscape. The pilot project builds upon earlier hypotheses regarding the chronology and function of the Sanchi dams and their relationship to religious and political history in Central India. The principal suggestion is that the earliest phase of dam construction coincided with the rise of urbanization and the establishment of Buddhism in central India between c. third and second centuries B.C.; and that they were connected with wet-rice cultivation as opposed to wheat, the main agricultural staple today. Similarities with intersite patterns in Sri Lanka, where monastic landlordism is attested from c. second century B.C. onward, have also led to the working hypothesis that the Sanchi dams were central to the development of exchange systems between Buddhist monks and local agricultural communities. The pilot project focused on two out of a total of 16 dam sites in the Sanchi area and involved scraping back dam sections created by modern road cuttings. This cast new light on aspects of dam construction and allowed for the collection of sediments and ceramics for OSL dating. The results confirmed the suitability of local sediments to OSL dating methods, as well as affirming our working hypothesis that the dams were constructed—along with the earliest Buddhist monuments in Central India—in the late centuries B.C. Sediment samples were also collected from cores hand drilled in the dried-up reservoir beds, for supplementary OSL dating and pollen analysis, which shed useful insights into land use.

Ancient dams, settlement archaeology and Buddhist propagation in central India: the hydrological background

Abstract A group of ancient dams (c. second—first century BC) was located during an archaeological study of the Sanchi area in central India. Comparison of reservoir volumes with estimated inflows suggests that their design was based on hydrological understanding.

The water balance of Lake Kyoga, Uganda

Abstract The annual water balance of Lake Kyoga is estimated by a comparison of upstream and downstream flows in the Nile channel during a period of reliable measurements (1940–1977), supported by rainfall records over the basin. The relative contributions of net lake rainfall and tributary inflows are estimated. Changes in annual rainfall and seasonal distribution are examined. Editor Z.W. Kundzewicz Citation Brown, E. and Sutcliffe, J.V., 2013. The water balance of Lake Kyoga, Uganda. Hydrological Sciences Journal, 58 (2), 342–353.

Historical water resources in South Asia: the hydrological background

Abstract The development of historical water resources in the South Asian subcontinent has been largely dependent on the hydrological background. The runoff patterns are derived from climate statistics and the historical developments in different areas are related to these patterns. Citation Sutcliffe, J., Shaw, J. & Brown, E. (2011) Historical water resources in South Asia: the hydrological background. Hydrol. Sci. J. 56(5), 775–788.

Harold Edwin Hurst: The Nile and Egypt, past and future

ABSTRACT H.E. Hurst spent some 60 years studying the Nile for the Egyptian government, and laid the foundation for a monumental set of hydrological records and investigations. His studies of the size of over-year reservoirs needed to maintain a given yield from Nile flows showed that this was greater than that based on random series. This finding, known as the Hurst phenomenon, was confirmed by other natural series and led to important advances in practical and theoretical statistics. His work led to the design of the Aswan High Dam and to continued research in Egypt. Editor D. Koutsoyiannis; Guest editor E. Eris

Water losses from the Sudd

ABSTRACT Water losses in the Sudd wetlands of South Sudan have significant effects on water resources available to Sudan and Egypt. These losses increased greatly after the dramatic rise of Lake Victoria in 1961–1964, but investigation into the cause and location of these increased losses has been hindered by the shortage of records after 1963 and their cessation after 1983. By linking flow records at key points within the Sudd with the distribution of vegetation before the rise, analysis of vegetation after the rise can throw light on the distribution of resulting losses and their causes. Although the increased flooding in the upper reaches of the Sudd has been noted, this paper draws attention to greatly increased inundation in the lower reaches, apparently from backwater flooding, which would affect any future proposal for the Jonglei Canal project.