The up and down sides of rotors relative to ridges

On 4/7/2016 7:54 PM, son_of_flubber wrote:
On Thursday, April 7, 2016 at 8:56:48 PM UTC-4, BobW wrote:
On 4/7/2016 6:26 PM, son_of_flubber wrote:
...
But what about my assumption that the lift side of the rotor is
generally found between the sink side of the rotor and the upwind
ridge? Or does this depend on the particular ridge and the particular
day?

I'll be surprised (shocked?) if anyone can point to a rotor that ever
lies UPwind of the wave-generating geographic feature, if that's what
you're wondering about,...

No. I'm only talking about rotor that is formed downwind of the
wave-generating topographic feature (aka Ridge A).

My thinking is that for a wind blowing towards the east, the top of the
rotor is also blowing east and the bottom of the rotor is blowing west, so
the lift side of the rotor is to the west of the sink side. This is
idealized because if the feature causing the wave is convoluted and
irregular, all sorts of chaotic interactions can result in unpredictable
patterns.


I may still not be fully understanding what you're puzzling over, but...yes,
rotors revolve with their "top" moving in the same direction of the overall
prevailing stream flow, their "bottom" moving against the large-scale stream
flow, their "back edge" (relative to the prevailing stream flow) moving down
toward the ground, and their "front edge" (relative to the prevailing stream
flow) moving up. Rotor "organization" in my experience is useful more as a
mental concept than as PIC-reality, though - situation/geography permitting -
if you believe yourself in rotor and averaging the wrong direction (i.e.
toward the ground below), moving upwind, against the overall stream flow is
often a useful tactic in striving to change "averagely down" to "averagely
up." In the Boulder, CO, region, some days that was a practical proposition,
others "surely you jest!"

Bob W.