Sea Level Change

Question 1

Sea level change

Answer 1

Factors combine 2 increase the risk of sea level change which threatens the lives of ppl who live near coasts
3 key factors that have contributed towards sea level change over diff time periods plus CC

Question 2

Eustatic change

Answer 2

Rising + falling of sea levels influenced by ice ages
Water is stored in the form of ice when the world is experiencing an ice age which causes the sea level 2 fall
As the world moves out of an ice age the ice melts. This results in the sea level rising again

Question 3

Isostatic change

Answer 3

Refers to the level of the land which is also influenced by ice ages
During an ice age the weight of the ice forces that land to sink
When the ice age has finished the melting of the ice causes the land to rebound back up like a spring

Question 4

Tectonic change

Answer 4

Causes land 2 either rise/sink at the boundaries where tectonic plates meet
A sudden change = movement of a plate can lead 2 a rise/fall in the seabed causing a change = sea level
Earthquakes out at sea can trigger a tsunami causing devastating effects 4 people living along coastlines

Question 5

Emergent vs Submergent coastlines

Answer 5

Cause the formation of different landforms

Question 6

Emergent coastlines

Answer 6

Cause the formation of raised beaches + fossil cliffs caused by isostatic rebound
Raised beach + fossil cliff are formed when following an ice age the land rebounds
Causes the original height of land 2 increase
Leaves behind a beach + fossil cliff higher than their original position

Question 7

Submergent coastlines

Answer 7

Submergent coastlines cause the formation = rias, fjords, Dalmatian coasts

Question 8

Ria

Answer 8

Flooded river valley formed when rising sea levels flood the valley often creating an estuary

Question 9

Fjord

Answer 9

E.g. of a flooded glaciated valley formed when a glacier erodes vertically creating a u-shaped valley

Question 10

Dalmatian coasts

Answer 10

Formed because of the arrangement of alternating rock types parallel 2 the coast

Question 11

Global warming + sea level change

Answer 11

International panel on climate change (IPCC)
Acknowledge that sea levels are rising from past + present data collected. The IPCC links this to global warming. Coastal flooding is a consequence of this

Question 12

Increased frequency of storms

Answer 12

Strong winds caused by storms create high energy destructive waves which have considerable erosional power
Increased energy of the sea will mean ,ore material can be transported + for greater distances. Could leave some areas vulnerable 2 erosion if they’re left w/o much protection
Frequency of storm surges will Inc. when combined w/ sea level rise these surges will reach further inland + cause more damage.

Question 13

Rising sea levels

Answer 13

Data = IPCC indicated 1901-2010 average sea levels have increased by 0.19m
Some of the contributing factors being linked 2 the melting of glaciers + ice sheets
E.g. Greenland + Antarctic ice sheets have been decreasing rapidly
Higher sea levels could cause higher tides + this would increase the frequency of coastal flooding
Higher tides could also remove more material from beaches leaving cliffs less protected

Question 14

Global warming

Answer 14

Evidence = IPCC indicates that between 1983-2012 the northern hemisphere experienced the warmest 30 year period of the last 1,400 Years
Changes in the worlds atmospheric temps are causing thermal expansion = oceans, melting of glaciers + ice sheets
Global warming = largely because of anthropogenic green gas (GHG) emissions
The conc = gases has risen rapidly since industrialisation