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 an accurate approximation for meteorological and environmental calculations.

2. How Does the Calculator Work?

The calculator uses the Magnus formula:

Where:

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

Explanation: The formula describes how the maximum amount of water vapor that air can hold increases exponentially with temperature.

3. Importance of Vapor Pressure Calculation

Details: Saturation vapor pressure is crucial for understanding humidity, cloud formation, precipitation processes, and various meteorological phenomena. It's also important in industrial processes involving evaporation and condensation.

4. Using the Calculator

Tips: Enter the temperature in degrees Celsius. The calculator will compute the saturation vapor pressure in hectopascals (hPa). Valid temperature range is typically between -50°C and 60°C for accurate results.

5. Frequently Asked Questions (FAQ)

Q1: What is saturation vapor pressure?
A: Saturation vapor pressure is the maximum pressure of water vapor that can exist in equilibrium with liquid water at a given temperature.

Q2: Why use the Magnus formula specifically?
A: The Magnus formula provides a good balance between accuracy and computational simplicity, making it widely used in meteorological applications.

Q3: How does temperature affect vapor pressure?
A: Vapor pressure increases exponentially with temperature. Warmer air can hold significantly more water vapor than colder air.

Q4: What are typical vapor pressure values?
A: At 0°C: ~6.11 hPa, at 20°C: ~23.39 hPa, at 40°C: ~73.78 hPa. These values double approximately every 10-11°C.

Q5: Are there limitations to the Magnus formula?
A: The formula is most accurate between 0°C and 60°C. For supercooled water or ice, different formulations may be more appropriate.