1. What is the Dry Adiabatic Lapse Rate?

The Dry Adiabatic Lapse Rate (DALR) is the rate at which the temperature of a parcel of dry air decreases as the parcel is lifted in the atmosphere under adiabatic conditions (no heat exchange with surroundings).

2. How Does the Calculator Work?

The calculator uses the DALR equation:

Where:

• \( g \) — Gravitational acceleration (9.8 m/s² on Earth)
• \( C_p \) — Specific heat capacity of dry air at constant pressure (1005 J/kg/K)

Explanation: The DALR represents the temperature change per unit altitude for a rising or sinking dry air parcel. The standard value on Earth is approximately 9.8°C per 1000 m (or about 5.4°F per 1000 ft).

3. Importance of DALR Calculation

Details: Understanding DALR is crucial in meteorology for predicting atmospheric stability, cloud formation, and weather patterns. It helps determine whether air parcels will continue rising (unstable) or resist vertical motion (stable).

4. Using the Calculator

Tips: Enter gravitational acceleration in m/s² (9.8 for Earth) and specific heat capacity in J/kg/K (1005 for dry air). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the typical value of DALR on Earth?
A: Approximately 9.8°C per 1000 m (or about 5.4°F per 1000 ft) when using standard values for g and Cp.

Q2: How does DALR differ from MALR (Moist Adiabatic Lapse Rate)?
A: MALR is lower (4-9°C/1000 m) because latent heat release from condensation partially offsets the cooling during ascent.

Q3: Why is DALR important in weather forecasting?
A: Comparing environmental lapse rate to DALR helps determine atmospheric stability and potential for thunderstorm development.

Q4: Does DALR vary on other planets?
A: Yes, it depends on the planet's gravity and atmospheric composition (which affects Cp).

Q5: How does altitude affect DALR?
A: The basic DALR equation assumes constant g and Cp, but at very high altitudes, these may vary slightly.