🎈Let's set sail and ride the waves of geography together!

Let's play with see-saws. Isostatic change is similar. It's about the change in land level relative to the sea level because of factors like tectonic uplift or ice sheet removal. Imagine your buddy Scandinavia and Canada going up at a rate of 20 mm/year!

Next, we have the roller coaster of sea level change. Imagine a world getting cold, glaciers advance, sea levels fall. Then it's so heavy, the land is pushed down. Suddenly, temperatures rise, ice melts, sea levels rise again and then the land bounces back up because the ice isn't heavy anymore.

According to the Valentin’s classification

• 🏖️Retreating coasts include submerged coasts and those where erosion beats emergence/deposition. Think of it like a chocolate bar getting eaten faster than it can be replenished!
• 🌄Advancing coasts include emerged coastlines and those where deposition happens rapidly. It's like you're adding more and more Lego bricks!

For instance, points A and X experienced uplift of around 100 m, but erosion at A reduced the effect of uplift. Think of it as trying to build a sandcastle while your naughty friend keeps knocking it down. Similarly, B and Y sank about 100m, but Y experienced deposition, so it didn’t change much relative to sea level.

Let's also note some features

• 🏞️Emerged coastlines have raised beaches (like Portland Raised Beach, UK), coastal plains, relict cliffs (like the Fall Line in the US), and raised mudflats (like the Carselands of the River Forth).
• 🌊Submerged coastlines have rias (drowned river valleys like River Fal, UK), fjords (drowned U-shaped valleys like Milford Sound, New Zealand), and fjards (drowned glacial lowlands).

Sand is a rebellious teenager, pushed around by the wind. The wind speed varies with height above a surface. The belt of no wind is only 1 mm above the surface. It's like being invisible in a crowd because you're short! If the sand grains stick out above this height, they are moved by a process called saltation.

Irregularities, like your messy room, cause the wind to speed up and move more material. On the leeward (or protected) side of irregularities, wind speed is lower, causing deposition to increase. It's like your clothes piling up behind the furniture!

Vegetation is the superhero who brings stability to the dunes. The oldest dunes are the furthest from the sea, while the youngest ones are closest to the shore. The dunes nearest the shore are harsher, windier, and saltier, called "yellow dunes." Plants like sea couch and marram can survive these tough conditions. Once the vegetation is established, it's like a shield against the wind. This makes the sand dune grow.

Over time, as the dune gets higher and the supply of fresh sand decreases, marram dies out and the soil becomes moister and more acidic. In the low points between the dunes (the slacks), conditions are wetter, and marsh vegetation may occur. Towards the back, "grey" dunes form due to the presence of humus in the soil.