Lakes, climate change

The problem of fluctuating lake levels is currently of major concern. The additional potential effects of climate change on water levels may further exacerbate the problem as will any major diversions of water out of the basin to support developments in the more arid regions of the continent. 

Here we revisit two important topics in limnology just to show that climate change studies that only include data from lakes are not applicable to reservoirs. Firstly, we show that temperature trends in reservoirs and lakes cannot be interpreted in the same way. Secondly, we show that drivers of the deep-water oxygen content in reservoirs and lakes can be very different. This last analysis will be used in the following section as the starting point for a new framework for climate change impact studies in reservoirs. 

O Reilly CM, Alin SR, Plisnier PD, Cohen AS, McKee BA (2003) Climate change decreases aquatic ecosystem productivity of Lake Tanganyika, Africa. Nature 424 766-768... 

Carvalho L, Kirika A (2003) Changes in shallow lake functioning response to climate change and nutrient reduction. Hydrobiologia 506 789-796... 

Many lakes in present-day arid regions were freshwater lakes in the wet period between 12,000 and 8,000 BP. Terraces and/or shorelines from that period extend well above the present lake or lacustrine plain. The same lakes were completely dry in the arid Late Pleniglacial period (20,000-13,000 BP). Even a comparatively minor climate change can upset sedimentation regimes in arid lands. 

Global climate change, air-quality degradation (coal, oil), lake acidification and forest damage (coal, oil), land disturbance and others, if hydrogen is produced by fossil fuels ... 

Fishes in Alpine floodplains are limited to cold stenothermic species such as the brown trout, and many alpine lakes are currently stocked to sustain the fishery. Water abstraction and flow regulation severely constrain the management of the fishery in Alpine waters today. The effects of climate change on the fishery are difficult to predict but could facilitate the upward migration of more cool water fishes in the future. The implications of these new fishes on aquatic food webs are not certain but could be substantial. 

Bajracharya SR, Mool P, Shrestha B (2007) Impact of climate change on Himalayan glaciers and glacial lakes Case studies on GLOF and associated hazards in Nepal and Bhutan. ICIMOD Publ, Kathmandu, p 119... 

Part 1, Alpine Water Resources, examines the hydrological basics, the impacts of climate change in the Swiss Alps, and human interventions in mountain waters. Part 11, Biogeochemistry and Pollution of Alpine Waters, deals with the chemistry of mountain rivers, the effects of acid deposition on high elevation lakes, the glaciers as archives of atmospheric deposition, and the occurrence of persistent organic contaminants. 

Varve or rhythmites chronology is another approach based on the examination of geological materials. In this model, the distribution of the laminated sediments formed in the bottom of the beds of dried-out lakes (as a consequence of the seasonal melting of glaciers and the subsequent deposition of coarse particles supplied by streams, followed by finer materials such as sand, silt, and clay) is analyzed and correlated with climate changes [64],... 

Cross SL, Seltzer GO, Fritz SC, Dunbar RB (2001) Late Quaternary climate change and hydrology of tropical South America inferred from an isotopic and chemical model of Lake Titicaca, Bolivia and Peru. Quat Res 56 1-9... 

Climate changes may also have significant effects on lake DOC concentrations. In a 20-year study of boreal lakes in the Experimental Lakes Area of northwestern Ontario, Schindler et al. (1997) reported that lake DOC concentrations declined by 15-25% as mean annual temperatures increased by 1.6°C, precipitation declined by 40%, and runoff declined by 70% due to increased evaporation and decreased precipitation. The primary reason for the decline in lake DOC was reduced inputs of DOC from terrestrial catchments, although in-lake removal of DOC also increased slightly via either increased acidification, UV light penetration, or microbial degradation. 

Water levels in the oceans were lower by over 150 m during the ice ages, and similar water level fluctuations occurred in lakes and inland seas due to climatic changes and tectonic events. The sea level changes influenced the near-shore regions in the following ways ... 

Johnson T. C. (1996) Sedimentary processes and signals of past climatic change in the large lakes of the East African Rift Valley. In The Limnology, Climatology, and Paleoclimatol-ogy of the East African Lakes (eds. T. C. Johnson and E. O. Odada). Gordon and Breach, Amsterdam. 

Ambrosetti W. and Barbanti L. (1999) Deep water warming in lakes an indicator of climatic change. J. Litnnol. 58, 1 -9. 

The discovery of hydrates in the natural environments initiated other hydrate monographs, with diverse topics of carbon dioxide sequestration," permafrost and oceanic environments," and seafloor stability and climate change." However, hydrate research proliferation has led to state-of-the-art records of the international hydrate community at three-year intervals at New York in 1993, Toulouse in 1996, Salt Lake City in 1999, and Yokohama in 2002. The fifth international meeting is scheduled on June 12-16, 2005 in... 

Anderson, R.Y. (1993) The varve chronometer in Elk Lake record of climatic variability and evidence for solar-geomagnetic 14C climate connection. In Bradbury, J.P. Dean, W. E. (Eds) Elk Lake, Minnesota Evidence for Rapid Climate Change in the North-central United States. Special Paper 276. Boulder, CO Geological Society of America, pp. 45-67. 

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