DA_Team 3
Track and Central Pressure Error Analysis
Comparison of JTWC and RSMC best-track data for Typhoon Hinnamnor,
focusing on positional track error and central pressure difference.
This page analyzes differences between RSMC and JTWC best-track datasets for Typhoon Hinnamnor. The comparison focuses on two main aspects: track position and central pressure. Track differences are calculated using the Haversine distance between corresponding 6-hourly positions, and intensity differences are compared using the central pressure values reported by RSMC and JTWC.
1. Track Comparison Map
The interactive map visualizes the 6-hourly best-track positions from RSMC and JTWC.
The blue line represents the RSMC track,
while the red line represents the JTWC track.
White dashed lines connect corresponding positions at the same time, showing the spatial difference between the two agencies.
2. Track Error Analysis
The spatial and directional bias analysis shows where and in which direction JTWC positions differ from RSMC positions. The radial plot indicates that the errors are distributed around the RSMC center without a clear one-directional bias.
The track error time series shows that most positional differences remain below 20 km. The mean track error is 13.33 km, suggesting that the two agencies generally produced similar track estimates during most of Hinnamnor’s life cycle.
3. Central Pressure and Intensity Difference
This time-series comparison shows central pressure estimates from RSMC and JTWC. Because lower central pressure indicates stronger typhoon intensity, the y-axis is reversed to emphasize intensification and weakening.
The pressure difference is calculated as JTWC minus RSMC. Negative values indicate that JTWC analyzed Hinnamnor as stronger, while positive values indicate that RSMC analyzed it as stronger.
The mean pressure bias is only +0.84 hPa, indicating that there is almost no overall systematic intensity bias between the two agencies. However, the sign of the pressure difference changes over time, meaning that the stronger-intensity interpretation alternates between RSMC and JTWC depending on the storm stage.
4. Error Characteristics and Distribution
This figure summarizes the relationship between typhoon intensity and track error, as well as the statistical distributions of track and pressure differences.
The scatter plot suggests that stronger typhoon intensity is associated with smaller track error. This may be because a well-developed typhoon has a clearer center, making the center position easier to identify consistently. In contrast, during the early or weakening stages, the center can become more ambiguous, increasing differences between agencies.
The track error distribution is right-skewed, with most errors concentrated at low values and a few larger outliers. The mean track error is 13.3 km, while the median is 11.1 km. The pressure difference distribution is centered near 0 hPa, supporting the interpretation that there is no strong overall intensity bias.