05-17-2017, 05:43 AM
Thanks for all the good responses. (Glad to see your voice more prominent, glinda)
I believe the rate of flow is significantly dependent on relief (steepness); with a gradual relief causing flow to spread and stall. I believe 1984 flow toward Hilo did this. Other flows have almost “galloped” downhill, e.g., the flow down the giant pali above chain of craters road.
So some threatened areas might be subject only to possibly manageable 1-3 meter high flow. It seems, as in the case of the Pahoa telephone poles wrapped in protection 2 years ago, increasing efforts are being made to identify ways to survive flows.
(Of course a flow hardened in a few several weeks and then followed another flow in the same place creates a bigger problem, though if the 1st flow is higher than the surrounding land, the subsequent flow will tend to avoid it and travel to the lower area.)
* * *
Sorry to pursue a question that is premised on the extreme outcome of telescopes being removed from Mauna Kea, but where would those low altitude sites be (for telescope construction)? (TomK mentioned this.)
Waimea plain (about 3,500 ft)? Kohala Mountain (5,480 ft.)? Saddle road (6,632 ft at highest point)? (A discussion point is how higher altitude improves observational capacity, a concept often cited by astronomers. How does top of Mauna Kea compare to say 6,600 feet at Saddle Rd? Is there a percentage figure on this?)
(I presume that telescope removal might mean that they could not be built on lower Mauna Kea slopes (e.g. above Mana Road or north side of Saddle Road on the mountain’s lower slope.)
I believe the rate of flow is significantly dependent on relief (steepness); with a gradual relief causing flow to spread and stall. I believe 1984 flow toward Hilo did this. Other flows have almost “galloped” downhill, e.g., the flow down the giant pali above chain of craters road.
So some threatened areas might be subject only to possibly manageable 1-3 meter high flow. It seems, as in the case of the Pahoa telephone poles wrapped in protection 2 years ago, increasing efforts are being made to identify ways to survive flows.
(Of course a flow hardened in a few several weeks and then followed another flow in the same place creates a bigger problem, though if the 1st flow is higher than the surrounding land, the subsequent flow will tend to avoid it and travel to the lower area.)
* * *
Sorry to pursue a question that is premised on the extreme outcome of telescopes being removed from Mauna Kea, but where would those low altitude sites be (for telescope construction)? (TomK mentioned this.)
Waimea plain (about 3,500 ft)? Kohala Mountain (5,480 ft.)? Saddle road (6,632 ft at highest point)? (A discussion point is how higher altitude improves observational capacity, a concept often cited by astronomers. How does top of Mauna Kea compare to say 6,600 feet at Saddle Rd? Is there a percentage figure on this?)
(I presume that telescope removal might mean that they could not be built on lower Mauna Kea slopes (e.g. above Mana Road or north side of Saddle Road on the mountain’s lower slope.)