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The day/night differences seem less drastic in the European examples. In fact, for January in both European examples the night temperatures decline faster with altitude than the days. Perhaps because both of these places sit in a deep valley so the low elevation location is unusually cold for its elevation.
Precipitation increases much more with elevation for the American locations. Either there was something atypical about my European locations, or the east-west direction of European mountain ranges mean they don't catch as much precipitation.
Figure is 3 is interesting; all the mountains follow the same profile. Mt. Washington isn't cold for its altitude and region, just especially high. The diurnal lapse rate cycle is shown in Figure 6.
From the latter paper on the low treeline in the Northeast US:
Within the Appalachian Mountain chain, Cogbill and White (1991) reported that treeline correlated with the 13°C July isotherm, whereas Daubenmire (1954) found that treeline locations in western North America correlated well with the 10°C July isotherm. Even taking in to account the fact that, in the northeastern United States, July 2002 was roughly one-half a degree warmer than normal (based on the 1961–1990 station norms for the six NOAA stations used here), these data support the idea that air temperatures at treeline in this region are warmer than those in the western USA. Treeline thus occurs at a lower elevation than would be expected on the basis of air temperature alone.
So the transition to no trees happens at a higher annual temperature in the Northeast US than the West.
Another interesting tidbit I found for those with an interest in the mountains of the Northeast US.
In the northern Appalachians, cloud ceiling is thought to control the boundary (Fig. 4) between low-elevation
deciduous and high-elevation coniferous forests frequent fog immersion is thought to also control the extent of spruce-fir forests in coastal Maine.
So, in other words the average elevation of the base of clouds on overcast days corresponds well to the transition between deciduous forest and conifer forest. In a sense, they're "cloud forests".
Two British examples. Fort William (100? feet) and Ben Nevis (4400 feet):
Jan Day: -3.5°F / 1000 ft (-6.4°C / km)
Jan Night: -3.2°F / 1000 ft (-5.9°C / km)
Jul Day: -4.4°F / 1000 ft (-8.1°C / km)
Jul Night: -3.2°F / 1000 ft (-5.9°C / km)
Precipitation: +20.1 in / 1000 ft (1677 mm / km)
The July daily lapse rate is high, similar to Mt. Washington. The precipitation increase is enormous, and the summit sounds exceptionally foggy and cloudy. For a short altitude range, Morecambe (3 m), and Malham Tarn (391 m)
Jan Day: -3.3°F / 1000 ft (-5.9°C / km)
Jan Night: -3.8°F / 1000 ft (-7.0°C / km)
Jul Day: -3.3°F / 1000 ft (-5.9°C / km)
Jul Night: -4.7°F / 1000 ft (-8.5°C / km)
Precipitation: +15.5 in / 1000 ft (1292 mm / km)
Some high night lapse rates, maybe because the sea level location gets a mild night influence from the ocean. Same high precipitation lapse rate, also similar to the Washington (Paradise) example.
I've heard that too about altitude having less of an impact on temperatures when the land around it is also fairly high up, but I can't remember the reasoning behind it. Doesn't altitude also make more of a difference in winter than in summer, and also at nighttime rather than daytime?
Perhaps the logic is:
1) Heating happens at the surface and warms the surrounding air
2) It's not just altitude but also the height above the surface
3) If the local air is mixed with air that arrived from an area where the surface is at low elevation, it will follow a normal profile. But if not mixed, it will be hotter than usual for the altitude.
For many mountain ranges, only a small amount of land is actually high, so the altitude-temperature difference follows normally. But if it's a plateau, the air might be warmer than one expect given the altitude if it's unmixed with the atmosphere from further away.
For places like Colorado, places at the foot of the mountains are clearly too hot for their elevation compared to places say 5000 feet up in the atmosphere above a sea level location. Taking Denver and using a typical lapse rate would give you a climate unrealistically hot, hotter than Texas for daytime temperatures. The daytime temperatures at the plateaus seem too hot more than the nights, which make sense given surface heating happens at the day. The mountain west looks like it has the hottest 700 mb level (around 10000? feet) temperatures in the country:
Effect looks weakest at night. 500 mb temperature have no pattern of being hotter in the Rockies, as 500 mb is well above the height of the terrain. 850 mb has an even stronger terrain, but for much of the mountain west, the surface pressure is lower than 850 mb, so the 850 mb temperatures are an extrapolation. And somewhere in Utah has a 45°C forecast 925 mb temperature...
Jan Day: -2.7°F / 1000 ft (-4.9°C / km)
Jan Night: -2.0°F / 1000 ft (-3.6°C / km)
Jul Day: -4.6°F / 1000 ft (-8.3°C / km)
Jul Night: -2.2°F / 1000 ft (-4.0°C / km)
Precipitation: +8.2 in / 1000 ft (680 mm / km)
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Sorry if I missed it but can you explain how you got the temp change with altitude which I assume these numbers are for. Are you saying Pinkham Notch has a 2.7 degrees colder average January during the day then Mt Washington? Or reversed? Even reversed that doesnt sound right from 2000' to 6300'. But maybe it is.
Sorry if I missed it but can you explain how you got the temp change with altitude which I assume these numbers are for. Are you saying Pinkham Notch has a 2.7 degrees colder average January during the day then Mt Washington? Or reversed? Even reversed that doesnt sound right from 2000' to 6300'. But maybe it is.
All the numbers I calculated are temperature per elevation change °F/1000 ft or °C/km. There's a negative sign in front of 2.7, so the number means increasing elevation = colder temperatures.
since it's -2.7°F / 1000 feet, you'd have to multiply by about 4.2 to get the total temperature change, since the elevation difference between the two stations is 4200 feet.
All the numbers I calculated are temperature per elevation change °F/1000 ft or °C/km. There's a negative sign in front of 2.7, so the number means increasing elevation = colder temperatures.
since it's -2.7°F / 1000 feet, you'd have to multiply by about 4.2 to get the total temperature change, since the elevation difference between the two stations is 4200 feet.
Thanks. Cool to see location comparisons but sounds like the general rule of thumb that every 1000' up temp drops about 3-5°. Good hiking rule to remember.
When flying into Kuwait City, I have noticed some interesting ambient temperature patterns (as indicated on passenger monitors).
During the summer, the lapse rate is very steep - much more than the average 1 degree C for 150 m. It could sometimes be 40 C on the ground and 0 C at 15,000 ft.
During the winter, the lapse rate is unusually small. On a clear night under a high pressure ridge, the difference between 5000 ft and sea level is almost nonexistent.
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