Temperature Anomaly Calculator Formula
Understand the math behind the temperature anomaly calculator. Each variable explained with a worked example.
Formulas Used
Temperature Anomaly
anomaly_c = observed_temp - baseline_tempAnomaly (Fahrenheit)
anomaly_f = (observed_temp - baseline_temp) * 1.8Variables
| Variable | Description | Default |
|---|---|---|
observed_temp | Observed Temperature(°C) | 15.2 |
baseline_temp | Baseline Average Temperature(°C) | 14 |
How It Works
What Is a Temperature Anomaly?
A temperature anomaly is the difference between an observed temperature and a long-term baseline average for the same location and time period.
Formula
Anomaly = Observed Temperature - Baseline Average
Anomalies are preferred over absolute temperatures for tracking climate change because they remove local biases and allow meaningful comparisons across different locations and elevations.
Worked Example
The global mean temperature is observed at 15.2°C against a 20th-century baseline of 14.0°C.
- 01Anomaly = 15.2 - 14.0 = 1.2°C above baseline
- 02In Fahrenheit: 1.2 x 1.8 = 2.16°F above baseline
Frequently Asked Questions
Why use anomalies instead of actual temperatures?
Anomalies remove the effect of location, altitude, and local climate. A station at sea level and one on a mountain can both show +1°C anomaly, meaning both are equally warmer than usual.
What baseline period is typically used?
Common baselines include the 1951-1980 average (NASA) or the 1961-1990 average (WMO). The choice of baseline shifts the values but not the trend.
What is the current global temperature anomaly?
As of the mid-2020s, the global temperature anomaly is approximately +1.2 to +1.5°C above pre-industrial levels (mid-1800s baseline).
Ready to run the numbers?
Open Temperature Anomaly Calculator