Projects:EASA PPL/Meteorology

Atmosphere

~~Thermosphere~~
~~Mesosphere~~
Stratosphere: Upper level, temperature constant
Tropopause:
- Boundary layer, Avg 36090ft, -56.5°C
- at equator: 55000ft, -75°C
- at polar: 25000ft, -45°C
Troposphere:
- Half the mass of atmosphere is in the lower 5km


	per 1000ft	per 100m
Absolute instability	>3°
Dry Adiabatic Lapse Rate	3°	1°
conditionally stable	2-3°
Average Environmental Lapse Rate (ISA) 15° @ MSL	1.98°	0.65°
Saturated Adiabatic Lapse Rate (Central Europe)	1.8°	0.6°
stable	<2°

Dew point	0.5°

Pressure altitude: Indicated altitude at 1013.25 hPa setting
Density altitude: pressure altitude corrected for non-ISA temperatures (120ft per 1°C change from ISA)
QNH: ..N.. nautical
True altitude:
Wind on hPa - Wind on height
Wind off hPa - Wind off height
High to low - beware below
Low to High - up in the sky
1) Correct altitude for pressure: 1hPa = 27ft
2) Correct altitude for Temp: 1% per 2.5°C change from ISA
- colder: indicated alt minus offset / warmer: indicated alt plus offset

Mountain-valley:
- Katabatic: at night down from the mountains
- Anabatic: up the mountain by day
Land-breeze: From land-to-water, during the night, weaker than sea-breeze
Sea breeze: From the sea to land, during the day
pressure gradient: diff between high and low
straight isobar: pressure gradient force + coriolis force
curved isobar: gradient wind: pressure gradient force + coriolis force + centrifugal force

Convective weather:
- Thunderstorms, hail, tornados, wind gusts, heavy showers, lightning strikes
Low pressure travelling in summer: between 45° - 70°