Sea level rise resulting from global warming is now a widely publicized concern with strategies being implemented to address it. However, global sea levels have fluctuated by several hundred meters from current sea levels and this essay proposes to examine the mechanisms of past and present sea level change as well as its geomorphological impacts on coasts. . causes of sea level change, it is important to define the different types of sea level change. Eustatic sea level, relative sea level, and water depth all have specific meanings (see Figure 1 below). Eustatic sea level is the global sea level and is measured between the sea surface and a fixed reference, which has always been the center of the Earth. Relative sea level is the distance between the sea surface and a local datum, such as the top of basement rocks in a sedimentary basin. Water depth is the distance between the sea floor and the sea surface (Coe et al 2005). The main causes of eustatic sea level change are due to variations in ocean water volume and changes in ocean volume. basins. Changes in seawater volume are controlled by the formation and melting of ice sheets and glaciers. When water accumulates as ice on land surfaces, it causes sea levels to fall, while during interglacial periods the opposite happens and sea levels begin to rise (Pethick 1984). This is called glacio-eustasy. In terms of the volume of water involved in this process, Pethick (1984) estimates that if all the world's ice melted, current sea level rise would increase by 40 to 60 meters, with Rothery (1998) and Coe et al (2005), suggesting that this height could reach 80 meters. Changes in the middle of paper ......ts and bedforms and thirdly, this relies on obsolete concepts (Cooper et al 2004). Global and local sea levels have varied considerably throughout Earth's history and are primarily controlled by glacio-eustasis, thermal expansion, and tectonic activity. Oxygen isotope records have helped to establish sea level changes over recent geological history and it is now known that sea levels in the British Isles have risen over the past 18,000 years, creating the beaches and coastline we see today. Current sea level rise is exacerbated by anthropological causes, which is a concern due to the millions of people living on coasts. Predicting the geomorphological effects of sea level transgression is difficult, although Bruun's rule of sea level change provides some, albeit limited, insight into predicting shoreline geomorphological changes...