| Summary: | In order to assess the impact of sea level rise on Water Management, it is useful to understand the mechanisrns that determine the level of the sea. In this study, a literature survey is executed to analyze these mechanisms. Climate plays a centra! role in these mechanisms, Climate mainly changes due to a disturbance in the balance of incoming and outgoing energy. The disturbance in the balance is accomplished when a.o. the concentration of trace gases (called together the Greenhouse gases or the effective C02 concentration) alters. Before the Industrial Revolution, natural processes only determined the effective CO2-concentration. However, since the Industrial Revolution the effective CO2-concentration has rapidly increased because of human activities, and has thus enhanced the global warming. This mechanism of global warming is called the greenhouse effect. Some feedback mechanisms such as ice and snow, water vapour and permafrost (permanently frozen soils) have amplified the greenhouse effect, while on the other hand a feedback mechanism such as oceans has counteracted the greenhouse effect. A doubling of effective CO2-concentration in the atmosphere is to be expected by the middle or end of the next century, depending on changes in emissions. It is generally expected that this doubling of the CO2-concentration will enhance the greenhouse effect. Consequently, the atmospheric temperature will rise some degrees. If the temperature rises, sea level rises due to the following processes: thermal expansion of ocean water; meltingof mountain glaciers and small icecaps; and ablation (melting and runoff, evaporation) of the polar ice sheets of Greenland and Antarctica. It is even possible that a great part of the West Antarctic lee Sheets may disintegrate, and thus, sea level may rise several meters. The sea level can change tens of meters within a geologically short time (in the order of millennia). This can be seen when sea level changes in the past are analyzed. However, since the present era is an interglacial, ...
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