1. What is the Magnus Formula?

The Magnus formula is an empirical relationship that calculates the saturation vapor pressure of water over liquid water as a function of temperature. It provides accurate estimates for meteorological and scientific applications.

2. How Does the Calculator Work?

The calculator uses the Magnus formula:

Where:

• \( e_s \) — Saturation vapor pressure (hPa)
• \( T \) — Temperature (°C)
• 6.112 — Reference vapor pressure at 0°C (hPa)
• 17.67 and 243.5 — Empirical coefficients

Explanation: The formula describes the exponential relationship between temperature and the maximum amount of water vapor the air can hold at that temperature.

3. Importance of Vapor Pressure Calculation

Details: Vapor pressure calculation is essential for weather forecasting, humidity measurement, climate studies, and various industrial processes involving air-water interactions.

4. Using the Calculator

Tips: Enter temperature in degrees Celsius. The calculator will compute the saturation vapor pressure in hectopascals (hPa).

5. Frequently Asked Questions (FAQ)

Q1: What is the range of validity for the Magnus formula?
A: The formula is valid for temperatures between -45°C to 60°C, though it's most accurate between 0°C and 50°C.

Q2: How does vapor pressure relate to humidity?
A: Relative humidity is the ratio of actual vapor pressure to saturation vapor pressure at the same temperature, expressed as a percentage.

Q3: Why are there different vapor pressure formulas?
A: Different empirical formulas have been developed for specific temperature ranges and applications, with varying levels of complexity and accuracy.

Q4: How does altitude affect vapor pressure?
A: Vapor pressure depends primarily on temperature, not altitude. However, boiling point and atmospheric pressure change with altitude.

Q5: Can this formula be used for ice?
A: No, this formula is for liquid water. Different coefficients are used for calculating vapor pressure over ice surfaces.