Questions tagged [planetary-boundary-layer]

The tag has no usage guidance.

2
votes
0answers
25 views

Is there a conceptual diurnal model for ozone profile?

So i know that there are diurnal patterns for virtual potential temperature that can be described conceptually (such as $\frac{\partial \theta_v}{\partial z}\approx 0$ in the mixed layer and $\frac{\...
4
votes
3answers
4k views

Is it less windy in a valley than on a hill?

Assume we have a mountain landscape without trees. Would it be less windy in a valley than on a hill, or would the wind just be the same? Or in other words, which of the two images below describe ...
4
votes
0answers
74 views

What timescales do eddies operate at in the planetary boundary layer?

What are the largest eddies within the planetary boundary layer? What timescales do the operate on? Edit: I'm talking about atmospheric eddies over land. So, eddies that are measured in [eddy ...
6
votes
2answers
706 views

SST and air temperature differences

I'm trying to understand what causes the sea-surface temperature (in the open ocean and coastal areas) and the air temperature immediately above it to be different. I know very little about the ...
11
votes
3answers
316 views

Wind profile below the aerodynamic roughness length

The vertical profile of horizontal windspeed is often given by the so-called "log-law": $$u(z)=(u^*/k)\ln(z/z_0),\ \mathrm{for}\ z>z_0,$$ which can be found here. As can be seen from the ...
13
votes
1answer
4k views

What is the difference between roughness length and zero plane displacement?

Both roughness length $z_0$ and zero plane displacement $d$ seemed to be defined as the height above the ground at which wind speed theoretically becomes zero. But wind speed is also supposed to go to ...
10
votes
1answer
89 views

Does within-canopy wind direction correlate with wind above the planetary bounday layer?

Wind above the planetary boundary layer (PBL) tends to be fairly smooth and constant over short periods of time. Below the planetary boundary layer, the smoothness is broken by eddies caused by ...