From e07a553414967d3a090c9b2feea2d1fdfab082a7 Mon Sep 17 00:00:00 2001
From: Matthias Nott <mnott@mnsoft.org>
Date: Thu, 09 Apr 2026 18:01:16 +0200
Subject: [PATCH] Graphic updates.
---
SPL Exam Questions EN/50 - Meteorology.md | 444 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
1 files changed, 426 insertions(+), 18 deletions(-)
diff --git a/SPL Exam Questions EN/50 - Meteorology.md b/SPL Exam Questions EN/50 - Meteorology.md
index 181bc51..94cb6c7 100644
--- a/SPL Exam Questions EN/50 - Meteorology.md
+++ b/SPL Exam Questions EN/50 - Meteorology.md
@@ -566,7 +566,12 @@
#### Explanation
-QNH is the altimeter setting adjusted to make the instrument read the elevation above mean sea level at the station. It is calculated by reducing the airfield QFE to sea level using the ISA temperature gradient. With QNH set, the altimeter reads the airfield elevation on the ground and true altitude above MSL in the air (assuming ISA conditions). Note that "true altitude" (answer A) accounts for actual temperature deviations from ISA — QNH gives indicated altitude, which may differ from true altitude in non-ISA conditions.
+QNH is the altimeter setting adjusted so the instrument reads the airfield elevation above mean sea level (MSL) when on the ground. It is calculated by reducing the airfield QFE to sea level using the ISA temperature gradient. With QNH set, the altimeter shows **indicated altitude above MSL** — this is height referenced to MSL, which is why answer A is correct.
+
+However, indicated altitude is not the same as true altitude. In non-standard temperature conditions, the actual height above MSL can differ from the indicated reading. Answer D ("True altitude above MSL") is therefore wrong — QNH does not correct for temperature deviations from ISA.
+
+- **Option B** describes what QFE gives (height above airfield), not QNH.
+- **Option C** describes what happens with the standard setting 1013.25 hPa (flight levels), not QNH.
#### Key Terms
@@ -1045,11 +1050,11 @@
- **QFE** = Atmospheric pressure at aerodrome elevation
- **ISA** = International Standard Atmosphere
-### Q57: What does the following symbol mean? (Arrow with one long barb and one short barb) ^t50q57
+### Q57: What does the following wind barb symbol mean? ^t50q57
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q57) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q57)
-> 
+
- A) Wind from NE, 30 knots.
- B) Wind from SW, 30 knots.
@@ -1062,7 +1067,19 @@
#### Explanation
-The arrow points towards the wind's origin. One long barb = 10 kt, one short barb = 5 kt. Total = 15 kt from the NE.
+A wind barb is the standard meteorological symbol for wind direction and speed. It has two ends: a **station end** (the dot) and a **barbed end** (the staff with feathers). The **feathers point toward where the wind is coming FROM** — i.e., the barbed end is upwind.
+
+Speed is read off the feathers:
+
+- Pennant (filled triangle) = 50 kt
+- Long barb (full feather) = 10 kt
+- Short barb (half feather) = 5 kt
+
+In this symbol the staff goes from the dot to the **NE**, with one **long barb (10 kt)** and one **short barb (5 kt)** = **15 kt**. So the wind is **from the NE at 15 kt**.
+
+
+
+Reference: [Wikipedia — Station model § Wind](https://en.wikipedia.org/wiki/Station_model#Wind)
### Q58: What are the wind speed and direction in the following METAR? LSZB 131220Z 28015G25KT 9999 SCT035 BKN075 10/06 Q1018 NOSIG= ^t50q58
@@ -1126,7 +1143,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q61) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q61)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
> **Synoptic chart:**
> 
@@ -1155,7 +1171,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q62) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q62)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
- **A)** Stratiform cloud cover.
- **B)** Convective cloud development.
@@ -1176,7 +1191,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q63) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q63)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
- **A)** A few scattered cumuliform clouds, rare precipitation, light turbulence, and excellent visibility.
- **B)** Extensive stratiform clouds with a gradually lowering cloud base and continuous rainfall.
@@ -1199,7 +1213,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q64) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q64)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
- **A)** Continental tropical air.
- **B)** Maritime tropical air.
@@ -1221,7 +1234,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q65) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q65)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
> **Synoptic chart Switzerland/Alps:**
> 
@@ -1249,7 +1261,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q66) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q66)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
> **Low Level Significant Weather Chart (OGDD70)**
> 
@@ -1289,7 +1300,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q67) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q67)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
- A) Crosswind from the left.
- B) Headwind.
@@ -1312,7 +1322,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q68) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q68)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
- **A)** At the centre of an anticyclone.
- **B)** In a transition zone between two air masses.
@@ -1334,7 +1343,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q69) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q69)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
- **A)** It will increase by 50%.
- **B)** It will remain constant.
@@ -1357,7 +1365,6 @@
[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q70) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q70)
-> *Source : BAZL/OFAC Série 1 - Branches Communes*
- **A)** At 11:00 LT conditions on this route will be difficult.
- **B)** At 09:00 LT conditions on this route will be critical.
@@ -1392,11 +1399,22 @@
#### Explanation
-Wind barb symbols point in the direction the wind blows from, with barbs on the upwind end indicating speed: a long barb equals 10 kt, a short barb equals 5 kt, and a pennant (triangle) equals 50 kt. The symbol shown points from the SW with two long barbs and one short barb, giving 10 + 10 + 5 = 25 kt from the southwest.
+A wind barb has two ends: a **station end** (the dot) and a **barbed end** (the staff with feathers). The **feathers point toward where the wind is coming FROM** — i.e., the barbed end is upwind.
+
+Speed is read off the feathers:
+
+- Pennant (filled triangle) = 50 kt
+- Long barb (full feather) = 10 kt
+- Short barb (half feather) = 5 kt
+
+Here the staff goes from the dot toward the **SW**, with **two long barbs (2 × 10 = 20 kt)** and **one short barb (5 kt)** = **25 kt**. So the wind is **from the SW at 25 kt**.
- **Options B and D** overstate the wind speed dramatically.
-
- **Option A** has the direction reversed — NE is the direction the wind blows toward, not from.
+
+
+
+Reference: [Wikipedia — Station model § Wind](https://en.wikipedia.org/wiki/Station_model#Wind)
### Q72: At what time of day or night is radiation fog most likely to form? ^t50q72
@@ -2027,10 +2045,22 @@
#### Explanation
-Wind barbs point in the direction the wind blows from, with speed indicated by barbs and pennants on the upwind end: a pennant = 50 kt, a long barb = 10 kt, a short barb = 5 kt. The symbol shows a wind from SSW with one pennant (50 kt) and two long barbs (20 kt), totalling 70 kt.
+A wind barb has two ends: a **station end** (the dot) and a **barbed end** (the staff with feathers). The **feathers point toward where the wind is coming FROM** — i.e., the barbed end is upwind.
-- **Options A and B** incorrectly identify the direction as NNE — wind barbs point FROM the wind source, not toward it.
+Speed is read off the feathers:
+
+- Pennant (filled triangle) = 50 kt
+- Long barb (full feather) = 10 kt
+- Short barb (half feather) = 5 kt
+
+Here the staff goes from the dot toward the **SSW**, with **one pennant (50 kt)** and **two long barbs (2 × 10 = 20 kt)** = **70 kt**. So the wind is **from the SSW at 70 kt**.
+
+- **Options A and B** have the direction reversed — wind barbs point FROM the wind source, not toward it.
- **Option D** overstates the speed to 120 kt.
+
+
+
+Reference: [Wikipedia — Station model § Wind](https://en.wikipedia.org/wiki/Station_model#Wind)
### Q102: What is the name of the fog that develops when a moist air mass moves horizontally over a colder surface? ^t50q102
@@ -4288,3 +4318,381 @@
- **Option B** describes the synoptic pressure setup only partially.
- **Option A** places the Ns on the north (lee) side, which is incorrect.
+### Q212: Which meteorological element is most important for the safety of a VFR flight? ^t50q212
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q212) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q212)
+
+- A) Wind direction and strength
+- B) Air temperature
+- C) Horizontal visibility
+- D) Amount and height of clouds above 1500 m/GND
+
+#### Answer
+
+C)
+
+#### Explanation
+
+For visual flight rules (VFR), horizontal visibility is the most critical element: below the regulatory minimum, the pilot can no longer maintain separation from terrain, obstacles, and other aircraft by sight alone. Wind direction, temperature, and cloud cover above 1500 m are important, but it is low clouds and reduced visibility that directly trigger VFR restrictions. The amount and height of clouds below 1500 m/GND (ceiling) is also critical, as a low ceiling can trap the pilot.
+
+---
+
+### Q213: Which meteorological situation reduces visibility the most? ^t50q213
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q213) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q213)
+
+- A) The approach of a polar air mass
+- B) High pressure
+- C) Fog
+- D) Foehn
+
+#### Answer
+
+C)
+
+#### Explanation
+
+Fog can reduce visibility to a few meters, or even less than 100 m, making it by far the most severe visibility reduction in surface meteorology. Foehn is generally associated with excellent visibility. High pressure often favors clear skies, except in winter where inversions can produce fog or stratus. A polar air mass can bring snow showers, but these reduce visibility less drastically than thick fog.
+
+---
+
+### Q214: From which altitude can the danger of gaseous embolism occur? ^t50q214
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q214) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q214)
+
+- A) From 10,000 m/AMSL
+- B) From 13,000 m/AMSL
+- C) From 16,000 m/AMSL
+- D) From 19,000 m/AMSL
+
+#### Answer
+
+B)
+
+#### Explanation
+
+Gaseous embolism (blood boiling) occurs when ambient pressure drops below the vapour pressure of human blood (approximately 47 hPa). This corresponds to about 19,000 m under standard conditions, but serious physiological problems related to extreme low pressure (outgassing of tissues) begin to manifest around 13,000 m/AMSL. This is why this altitude is used as the critical danger threshold in aviation regulations.
+
+---
+
+### Q215: In a mercury barometer, what is found in the tube above the mercury? ^t50q215
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q215) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q215)
+
+- A) Air
+- B) Nitrogen
+- C) A practically air-free space (Torricelli vacuum)
+- D) Water vapour
+
+#### Answer
+
+C)
+
+#### Explanation
+
+The mercury barometer works thanks to the partial vacuum created at the top of the sealed tube: when the tube is inverted in a mercury trough, atmospheric pressure supports a mercury column of approximately 760 mm, leaving a nearly vacuum space at the top (Torricelli vacuum). If there were air, nitrogen, or significant water vapour pressure, these would oppose the rise of mercury and distort the measurement.
+
+---
+
+### Q216: Which instrument is used to measure barometric air pressure? ^t50q216
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q216) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q216)
+
+- A) The thermometer
+- B) The mercury barometer
+- C) The psychrometer
+- D) The Magdeburg hemispheres
+
+#### Answer
+
+B)
+
+#### Explanation
+
+The mercury barometer measures atmospheric pressure by balancing the weight of a mercury column against air pressure. The thermometer measures temperature, the psychrometer measures relative humidity (by the difference between dry-bulb and wet-bulb thermometers), and the Magdeburg hemispheres were a historical demonstration of atmospheric pressure, not a standard measuring instrument.
+
+---
+
+### Q217: Which instrument is used to measure wind speed at a meteorological station? ^t50q217
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q217) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q217)
+
+- A) A weather flag
+- B) A windsock
+- C) A rotary cup anemometer
+- D) A kite
+
+#### Answer
+
+C)
+
+#### Explanation
+
+The anemometer (in particular the cup anemometer) is the standard instrument for measuring wind speed at meteorological stations. The windsock and weather flag give approximate visual indications but do not provide precise measurements. Kites were used historically by pioneers such as Benjamin Franklin but are not standard measuring instruments. Ultrasonic and hot-wire anemometers are modern variants.
+
+---
+
+### Q218: What is the chart commonly used to compile wind statistics for a given location (e.g., an airport)? ^t50q218
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q218) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q218)
+
+- A) The wind rose
+- B) The wind triangle
+- C) The wind polygon (frequency rose)
+- D) The isotachs
+
+#### Answer
+
+C)
+
+#### Explanation
+
+The wind polygon (frequency rose) shows, for each directional sector, the frequency and average speed of winds observed over a long period at a given location - very useful for planning runway orientation. The wind rose is the figure showing the 16 cardinal and intercardinal directions, but it is not a statistical chart. The wind triangle is an air navigation tool (drift calculation). Isotachs are lines of equal wind speed on a weather chart.
+
+---
+
+### Q219: What is meant by the "polar front jet stream"? ^t50q219
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q219) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q219)
+
+- A) A warm, strong ascending current ahead of the polar front
+- B) A zone of strong surface wind parallel to the polar front
+- C) A zone of very strong wind at the boundary of the tropopause
+- D) A strong descending wind after the passage of the polar front
+
+#### Answer
+
+C)
+
+#### Explanation
+
+The polar jet stream is a band of very strong winds (often 100-300 km/h) that forms at the boundary between cold polar air and warm subtropical air, in the upper troposphere (approximately 8-12 km altitude), near the tropopause. It results from the strong horizontal temperature gradient between these air masses. Its effect on the upper-level pressure gradient is significant and it guides the track of depressions at our latitudes.
+
+---
+
+### Q220: At what height above an obstacle are mechanical turbulences strongest? ^t50q220
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q220) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q220)
+
+- A) 150 m/AGL (above the obstacle)
+- B) 500 m/AGL
+- C) 1000 m/AGL
+- D) 2000 m/AGL
+
+#### Answer
+
+A)
+
+#### Explanation
+
+Mechanical turbulence generated by airflow around an obstacle (building, tree, hill) is most intense in the immediate downstream zone, up to approximately 150 m above the top of the obstacle. In this zone, eddies and wind shear are at a maximum. Beyond this, turbulence gradually decreases with altitude. For approach and landing, it is therefore recommended to maintain a minimum altitude margin of 150 m above obstacles upstream of the runway.
+
+---
+
+### Q221: Under which conditions do the strongest thermal and mechanical turbulences occur at noon? ^t50q221
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q221) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q221)
+
+- A) Calm wind, hilly region, clear sky
+- B) Calm wind, flat region, 5/8 Cu
+- C) 25 kt wind, hilly region, clear sky
+- D) 25 kt wind, hilly region, 5/8 Cu
+
+#### Answer
+
+D)
+
+#### Explanation
+
+The strongest turbulence results from the combination of thermal and mechanical effects: strong wind (25 kt) generates significant mechanical turbulence over hilly terrain. The presence of 5/8 cumulus indicates active thermal convection. This combination - strong wind plus relief plus convection - produces turbulence far exceeding what either factor alone would generate. Calm wind produces only weak thermals, and a clear sky with strong wind gives mainly mechanical turbulence without thermal reinforcement.
+
+---
+
+### Q222: When is water described as supercooled in a cloud? ^t50q222
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q222) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q222)
+
+- A) When the cloud produces snow
+- B) When the cloud contains ice crystals
+- C) When water droplets remain liquid below 0°C
+- D) When the water temperature is around 0°C
+
+#### Answer
+
+C)
+
+#### Explanation
+
+Supercooled water is liquid water that remains in liquid state even when its temperature is below 0°C (down to approximately -40°C). This is possible because very pure droplets suspended in clouds lack freezing nuclei. Supercooled water is particularly dangerous for aviation because it freezes instantly on contact with the cold surface of an aircraft, producing rime or clear ice. It is encountered mainly in cumulus, altocumulus, and nimbostratus between 0°C and -20°C.
+
+---
+
+### Q223: What is the width of the precipitation zone in a cold front? ^t50q223
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q223) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q223)
+
+- A) 10-30 km
+- B) 90-100 km
+- C) 150-300 km
+- D) 500-1000 km
+
+#### Answer
+
+B)
+
+#### Explanation
+
+The precipitation zone associated with a cold front is narrow (approximately 90-100 km) but intense: the cold front advances rapidly, forcing warm air to rise violently. This produces cumulonimbus clouds with heavy showers, thunderstorms, and sometimes hail. In contrast, the warm front has a much wider precipitation zone (150-300 km) but more continuous and less intense. This width difference explains why cold front disturbances are brief and violent, while warm front ones are long and gradual.
+
+---
+
+### Q224: How does visibility change when flying VFR from a cold air sector toward a warm front? ^t50q224
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q224) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q224)
+
+- A) Visibility improves
+- B) Visibility deteriorates
+- C) Visibility remains the same
+- D) None of the answers is valid
+
+#### Answer
+
+B)
+
+#### Explanation
+
+Advancing from cold air (polar air mass with good visibility) toward a warm front, the pilot encounters a progressive deterioration: cirrus thickens to cirrostratus, then altostratus, the ceiling lowers, and precipitation begins (rain or drizzle). Visibility deteriorates as the cloud layer thickens and precipitation becomes continuous. This gradual degradation gradient is a typical characteristic of warm front approach, in contrast to the cold front which abruptly deteriorates then rapidly improves conditions.
+
+---
+
+### Q225: What is the width of the precipitation zone in a warm front? ^t50q225
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q225) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q225)
+
+- A) 10-30 km
+- B) 80-100 km
+- C) 150-300 km
+- D) 500-1000 km
+
+#### Answer
+
+C)
+
+#### Explanation
+
+The warm front is characterized by a gently sloping frontal surface (approximately 1:100 to 1:150), meaning warm air rises very gradually over cold air across a large horizontal distance. This creates a wide precipitation band (150-300 km) extending well ahead of the surface front position. Precipitation is generally continuous, less intense than for a cold front, and accompanied by nimbostratus and altostratus.
+
+---
+
+### Q226: How does the cloud base change when flying VFR from a cold air sector toward a warm front? ^t50q226
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q226) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q226)
+
+- A) The cloud base drops suddenly
+- B) The cloud base drops gradually
+- C) The cloud base rises suddenly
+- D) The cloud base rises gradually
+
+#### Answer
+
+B)
+
+#### Explanation
+
+Approaching a warm front, the typical cloud sequence begins with high-altitude cirrus (very high base), followed by cirrostratus, altostratus, and then nimbostratus whose base can be very low (a few hundred metres). This ceiling drops gradually as the pilot approaches the front - a progressive warning that allows time to react, in contrast to the cold front which abruptly deteriorates conditions.
+
+---
+
+### Q227: Which zone of an occlusion is most active? ^t50q227
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q227) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q227)
+
+- A) The zone away from where the warm and cold fronts meet
+- B) The zone near where the warm and cold fronts meet (triple point)
+- C) The occlusion produces the same activity throughout its length
+- D) None of the answers is valid
+
+#### Answer
+
+B)
+
+#### Explanation
+
+An occlusion forms when the cold front, which advances faster, catches up with the warm front and lifts the warm sector off the ground. The most active zone - with the strongest winds, most intense precipitation, and most likely thunderstorms - is near the triple point (occlusion point), where both fronts meet and available energy is at its maximum. At the extremities of the occlusion, activity decreases progressively.
+
+---
+
+### Q228: When is the term "mist" used? ^t50q228
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q228) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q228)
+
+- A) Visibility is between 1000 and 8000 m
+- B) Visibility is between 1000 and 5000 m
+- C) Visibility is between 1000 and 3000 m
+- D) Visibility is below 1000 m
+
+#### Answer
+
+A)
+
+#### Explanation
+
+By international meteorological convention, mist is reported when visibility is between 1000 m and 8000 m due to the presence of fine water droplets or ice crystals in suspension. Below 1000 m visibility caused by condensed water vapour, the phenomenon is called fog. Above 8000 m, visibility is considered good. This distinction is important for METARs and VFR conditions.
+
+---
+
+### Q229: How do temperature, dew point, and relative humidity behave in fog? ^t50q229
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q229) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q229)
+
+- A) High relative humidity but temperature remains well above dew point
+- B) Low relative humidity and temperature far from dew point
+- C) Temperature equals dew point and relative humidity is equal to or close to 100%
+- D) Temperature, relative humidity, and dew point are all three equal to each other
+
+#### Answer
+
+C)
+
+#### Explanation
+
+Fog forms when air is saturated, i.e., when air temperature drops to the dew point (or humidity increases to saturation). At this point, relative humidity reaches 100% and water vapour begins to condense into fine suspended droplets. Temperature and dew point therefore become practically equal, while relative humidity approaches 100%. Option D is incorrect because relative humidity is a different quantity from temperature.
+
+---
+
+### Q230: What are the different stages of a thunderstorm cloud? ^t50q230
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q230) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q230)
+
+- A) Build-up, mature, dissipation
+- B) Cumulus, cumulonimbus, rain
+- C) Beginning, cumulonimbus, dissolution
+- D) Early stage, middle stage, final stage
+
+#### Answer
+
+A)
+
+#### Explanation
+
+A cumulonimbus (thunderstorm cloud) passes through three well-defined stages. The build-up stage (or cumulus stage): dominant updrafts, the cell grows upward. The mature stage (stabilisation): intense updrafts and downdrafts coexist - this is the most dangerous stage with lightning, hail, violent gusts, and heavy precipitation. The dissipation stage: downdrafts dominate, the cloud gradually evaporates and the thunderstorm weakens.
+
+---
+
+### Q231: What effect does icing have on a glider passing through cold precipitation? ^t50q231
+
+[DE](../SPL%20Exam%20Questions%20DE/50%20-%20Meteorologie.md#^t50q231) · [FR](../SPL%20Exam%20Questions%20FR/50%20-%20M%C3%A9t%C3%A9orologie.md#^t50q231)
+
+- A) Carburetor icing only
+- B) No consequence on aerodynamic performance
+- C) Within minutes, the glider can lose the ability to fly
+- D) Only minor consequences due to weight overload
+
+#### Answer
+
+C)
+
+#### Explanation
+
+Icing is particularly critical for gliders: their performance depends on a very precise wing profile with thin margins. Ice accumulating on the leading edge deforms the aerofoil profile, increases drag and reduces lift, lowers the stall speed, and adds weight. These combined effects can make the aircraft uncontrollable within minutes. Unlike powered aircraft, gliders generally have no anti-icing systems, making them extremely vulnerable. Preventive avoidance is the only effective measure.
+
--
Gitblit v1.3.1