climate change and coasts

• isostatic change - refers to level of land. Occurs locally.

  • during an ice age , weight of ice forces the land to sink
  • when ice age has finished , melting of ice causes land to bounce back up
• tectonic change - where tectonic plates meet , land either rises or sinks at boundaries.

  • sudden change in movement of a plate can lead to a rise or fall in seabed , causing change in sea level
• eustatic change - rising and falling of sea levels , influenced by ice ages. Occurs globally.

  • water is stored in form of ie when world is experiencing an ice age , causes sea level to fall
  • as world moves out of ice age, ice melts , results in sea level rising
• evidence from IPCC indicates that between 1983-2012 , Northern Hemisphere experienced warmest 30 year period of the last 1,400 years
• changes in global temperature is causing thermal expansion in oceans , melting of glaciers and ice sheets
• effects on the coast due to climate change:

  • sea levels rise
  • increased energy of sea = more erosion
  • frequency of storm surges will increase and will reach further inland
• sea levels rising - 1901 to 2010 , sea levels increased by 0.19m
• higher sea levels = higher tides , increase frequency of coastal flooding
• higher tides could remove material from beaches , leaving cliffs less protected
• climate change is changing frequency and intensity of low-pressure depressions and tropical storms
• rising global temperatures causing oceans to warm , triggering low pressure systems - increases risk of coastal flooding and creates unusual weather conditions