1. What is the Magnus Formula?

The Magnus formula is an empirical relationship that describes the saturation vapor pressure of water over liquid water as a function of temperature. It provides an accurate estimation of vapor pressure across a wide range of temperatures relevant to meteorological and environmental applications.

2. How Does the Calculator Work?

The calculator uses the Magnus formula:

Where:

• \( e_s \) — Saturation vapor pressure (hPa)
• \( T \) — Temperature in degrees Celsius (°C)
• \( \exp \) — Exponential function

Explanation: The formula calculates the maximum amount of water vapor that air can hold at a given temperature before condensation occurs.

3. Importance of Vapor Pressure Calculation

Details: Vapor pressure calculations are essential in meteorology for humidity measurements, in engineering for HVAC system design, and in environmental science for understanding evaporation processes and climate modeling.

4. Using the Calculator

Tips: Enter the 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, which covers most environmental conditions.

Q2: How accurate is the Magnus formula?
A: The formula has an accuracy of about ±0.1% for temperatures between 0°C and 50°C compared to more complex thermodynamic equations.

Q3: What units does the formula use?
A: The formula uses temperature in degrees Celsius and returns vapor pressure in hectopascals (hPa), which is equivalent to millibars.

Q4: Can this formula be used for ice?
A: No, this specific formula is for liquid water. Different coefficients are used for calculating vapor pressure over ice.

Q5: Why is vapor pressure important in weather forecasting?
A: Vapor pressure helps determine humidity levels, which affects cloud formation, precipitation, and overall weather patterns.