Chapter 6 paragraph 3 rising sea levels & protection

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Slide 1: Slide
AardrijkskundeMiddelbare schoolmavo, havoLeerjaar 2

This lesson contains 10 slides, with interactive quiz and text slides.

time-iconLesson duration is: 45 min

Items in this lesson

Slide 1 - Slide

At the end of this lesson
why the sealevel is rising and how we protect the coast in the Netherlands

Slide 2 - Slide

Rising sea levels
Melting land ice + expanding sea water


Why does melting sea ice not make a difference?

Slide 3 - Slide

Relative sea level rise
subsidence + sea level rise


Subsidence makes the land lower in relation to the sea level

Slide 4 - Slide

Subsidence cause 1
During the ice age Scandinavia sank about 250 meters
--> cause: a kilometers thick layer of land ice
--> the ground in Scandinavia is now rising back up
--> the Netherlands is sinking from a 'see-saw' effect 

Slide 5 - Slide

Subsidence cause 2
Low-lying areas of the Netherlands: subsidence from dewatering: without dewatering the soil is too wet for agriculture
Especially in peatlands: 
- peat = soggy, spongy soil typ
 - composed from dead plant matter
- when you remove water: soil collapses 
- part of peat above water surface: exposed to oxygen: decomposition: soil sinks more

Slide 6 - Slide

Subsidence cause 3
Groningen: subsidence because of mineral extraction --> natural gas

Slide 7 - Slide

Sand as protection
  • Measures to protect the coast:
  • Dike improvement
  • Dune improvement with sand 

Sand suppletion: adding sand. Why? 1. The waves lose their destructive force, 2. Dunes become higher and wider because the wind blows the sand onto the dunes.  

Slide 8 - Slide

To work
  • Read paragraph 6.3 
  • Make assignments 5, 6 and 7
  • 8 minutes silence, after that you can discuss with your neighbour. 
timer
8:00

Slide 9 - Slide

Which three things cause subsidence in the Netherlands?

Slide 10 - Open question