1.2 evolve over climate change

• The physical factors that affect global temperatures and the volume of water in ocean 

  -variations in the hearts orbit around the sun 

  -variations in the amount of energy produced by the sun

  -changes in the composition of ​atmosphere due to volcanic eruptions which reduce incident solar radiation 

  -variations in the tilt of the earth's axis 
• Emergent landforms 

  Landforms shaped by wave processes during times of high sea level are left exposed when sea level falls 
• Raised beaches, marine terraces and abandoned cliffs- raised beaches are areas of former shore platforms that† are left at a highway level than the present sea level

  Behind the beach along emergent coastlines there may be abandoned cliffs with wave-cut notches, caves, arches and stacks 

  Marine terraces are formed similar to raised beaches, but it takes much longer. This means they are larger in extent
• Modification of landforms 

  In the post glacial period, warmer and wetter conditions have led to the development of vegetation cover on many such exposures making it more difficult to recognise. With further warming continued degrading is likely to occur with chemical weathering becoming more influential. Biological weathering on the raised beach may also become more significant with the colonisation of the surface by increasing numbers of marine organisms such as limpets and whelk.

  If temperatures increase sufficiently
• Climate change and sea level rise 

  An increase in global temperatures leads to higher rates of melting ice stored on the land in ice sheets, ice caps and valley glaciers. As a consequence there is a global increase in the volume of water in the ocean store and the sea levels will rise 

  As temperatures rise, water molecules expand and this also leads to an increased volume 
• Rias- are submerged river valleys, formed as sea levels rise. The lowest part of the rivers course and the floodplains may be completely drowned, but the higher land forming the tops of the valley sides and the middle upper part remains exposed

  In cross section rias they have shallow water becoming increasingly deep towards the centre, the exposed valley sides are gently sloping

  They are typically underlain by alluvial deposits in buried channels that were eroded by the rivers that flowed down to the lower sea  levels of glacial periods.
• Fjords- are submerged glacial valleys, they have steep almost cliff like valley sides and the water is uniformly deep. They consist of glacial rock basin with a shallowere section at the end known as the threshold, this results from lower rates of erosion at the seaward end of the valley where the ice thinned in warmer conditions

  They also have much straighter planforms than rias as the glacier would have truncated any interlocking spurs present
• Shingle beaches- when sea level falls as the volume of the land based ice gowns, the large areas of the new land emerge from the sea. Sediment accumulates on this surface deposited by rivers, meltwater streams and low energy waves. As sea levels rose at the end of the last glacial period, wave action pushes these sediments onshore, in some places they beaches at the base of former cliff lines, elsewhere they may form tombolos and bars
• Modification of landforms 

  Both rias and fjords may be modified by the wave processes acting on their sides at the present day sea level, the sides may also be affected by subaerial processes may eventually lead to a reduction in the steepness of the valley sides of fjords 

  Marine erosion is also likely to increase due to stormier conditions and larger waves 

  Shingle beaches being composed of unconsolidated material, are especially vulnerable to modification

  With further sea level rise predicted shingle may well be moved even further