Very useful video! On question 4 of the bubble quiz (11:00) , wouldn't A also be a correct answer? From my understanding, let's say there was a building blocking an air canyon in an urban area which will therefore force wind to scale the wall and go over the top or around the side of this building. After the air has travelled over the top of the building, it can be sucked down due to the difference in pressure as this area is sheltered from the wind meaning there is less air traffic, compared to above the building which has a fast flowing movement of the air. When the air is pulled down behind the building, the majority of it is goes down at an angle a few metres past the building, this pushes the air on the ground to the face of the back of the building which then makes a smaller amount of air go up the backside of the building. when this smaller airflow reaches the top of the building, it is met with the much stronger current of air which then pushes it down at a shallower angle effectively making a vortices or swirling air. I can sometimes see this with dust or leaves. Hopefully the explanation makes sense. I read an article a few months ago however that was articulated much better.
Very useful video! On question 4 of the bubble quiz (11:00) , wouldn't A also be a correct answer? From my understanding, let's say there was a building blocking an air canyon in an urban area which will therefore force wind to scale the wall and go over the top or around the side of this building. After the air has travelled over the top of the building, it can be sucked down due to the difference in pressure as this area is sheltered from the wind meaning there is less air traffic, compared to above the building which has a fast flowing movement of the air. When the air is pulled down behind the building, the majority of it is goes down at an angle a few metres past the building, this pushes the air on the ground to the face of the back of the building which then makes a smaller amount of air go up the backside of the building. when this smaller airflow reaches the top of the building, it is met with the much stronger current of air which then pushes it down at a shallower angle effectively making a vortices or swirling air. I can sometimes see this with dust or leaves. Hopefully the explanation makes sense. I read an article a few months ago however that was articulated much better.