On August 2, 2022, former Speaker of the House Nancy Pelosi became the highest-ranking U.S. official to visit Taiwan in more than 25 years. The trip triggered an unprecedented military response from Beijing. That month, the People’s Liberation Army (PLA) flew 446 sorties into Taiwan’s self-declared air defense identification zone (ADIZ).

Beijing has increasingly demonstrated its willingness to make incursions into Taiwan’s airspace, actions the Commander of the U.S. Indo-Pacific Command, Samuel Paparo, has characterized as “rehearsals.” These gray-zone operations achieve more than to train Beijing’s forces. According to China expert Craig Singleton, they also serve to erode confidence in Taiwan’s leaders, increase skepticism of U.S. support for Taiwan, and convince Taiwanese that “resistance is futile.”

Greater transparency and accessibility of the data Taiwan’s Ministry of National Defense (MND) publishes may serve to bring clarity and encourage data-centered discussions about the direction of Taiwan’s security policy. To date, there is no known tracker that consolidates the geospatial data available across multiple datasets related to the Taiwan Strait into one single interactive map. This project plants the seed for a powerful tool with potential research and early-warning applications.

Background

In September 2020, the MND began releasing 24-hour reports on incursions into Taiwan’s ADIZ by PLA aircraft and vessels. These updates, which include textual data and map visualizations, provide valuable insight into PLA activity in the waters and airspace around Taiwan, including the quantity, time frame, and general coordinates of ADIZ violations.

Objectives

This project is an attempt to build an interactive map that visualizes data published by the MND on an aggregate level. It serves as an exploratory model and isolates five unique political events from 2024 to study PLA response over a 10-day period. The short-term goal of the project is to create a visual tracker that is updated in real time and retroactively maps all information published by the MND since September 2020.

This will enable civilian analysts to: (1) identify significant peaks and clusters in PLA activity by ADIZ sector, (2) observe patterns and trends in PLA activity surrounding Taiwan, and (3) select specific time frames for further spatial analysis.

There is a longer-term objective to introduce additional parameters, including weather, aircraft type, and textual data drawn from political speeches, to obtain insights into the interplay among these variables.

Data Description

This prototype relies on open-source data published on a daily basis by the MND, and aggregated and organized by Gerald C. Brown and Benjamin Lewis into the Taiwan ADIZ Violations dataset. The approximate coordinates of the ADIZ sectors were estimated using maps created by Louis Martin-Vézian of CIGeography due to challenges with obtaining precise coordinates as defined by the MND.

The following events in 2024 were selected for their political significance: (1) President Xi Jinping’s New Year’s Address delivered on December 31, 2023, (2) Taiwan’s Presidential Election on January 13, 2024, (3) the Inauguration of President Lai Ching-te on May 20, 2024, (4) President Xi Jinping’s National Day Address delivered on September 30, 2024, and (5) President Lai Ching-te’s Double Ten Address delivered on October 10, 2024.

Methodology

This project was developed in the R programming environment using Positron. The visualization is structured around three blocks of code, each of which map Taiwan’s ADIZ with increasingly levels of detail and interactivity.

1. The first block creates an overlay of ADIZ sector polygons onto a map of Taiwan.

2. The second block populates each ADIZ sector with the total number of PLA aircraft reported over a 10-day period following each political event.

3. The third block uses interactive sliders to animate PLA aircraft activity day-by-day across the ADIZ sectors over a 10-day event window.

Results

Taiwan’s ADIZ Sectors

Cumulative PLA Aircraft Activity by ADIZ Sector, 10 Days Post-Event

Daily PLA Aircraft Activity by ADIZ Sector, 10 Days Post-Event

Discussion

A preliminary observation of the model leads to several key findings. First, the pattern suggests Beijing uses the PLA’s incursions into Taiwan’s ADIZ as a response to events in Taipei rather than as a means to project its power. Second, China often delays its military reactions with varying lengths, a finding that is consistent with previous literature on the subject. Third, the PLA’s ADIZ violations occur most often in Taiwan’s Southwest ADIZ sector. The inclusion of additional data points would facilitate greater insight into China’s decision-making calculus on PLA exercises around Taiwan.

Limitations

Any map is only as reliable as its underlying data. Citing the sensitive nature of the information, the MND leaves important gaps in the data it makes available to the public. This includes PLA flight paths, the time of the incursions, data collected before September 2020, and the delineations of the ADIZ sectors.

More work is needed before this tool can become functional and reliable for public use. Over time, technology may have the potential to automate the process of reading reports published by the MND and other organizations, updating datasets, and mapping data points onto the visual tracker.

Implications

This tool, when paired with the timeline of political events, locations of critical infrastructure, PLA activity near other countries, or other relevant datasets, provides a foundation for addressing broader questions concerning Beijing’s objectives in the region. With more historical and future data points, it can begin to answer questions like: Are there blackout periods when the PLA refrains from performing exercises? Which regions see the most PLA activity, and why? What do long-term patterns reveal about Beijing’s capabilities and motives?

Conclusion

By virtue of being self-declared, Taiwan’s ADIZ may not be enforceable. But if the data suggest a rise in military activity in Taiwan’s airspace and waters, then Beijing will have succeeded in changing the status quo with few consequences. That will have far-reaching implications for security in the region.

Taipei is now faced with the unenviable task of making its population aware of the military threat it faces without sending its people into a panic. Outside observers have often marveled at the indifference or absence of concern many Taiwanese seem to show toward China’s frequent military flyovers. At the end of the day, Taiwanese attitudes towards Beijing’s incursions should not be equated with their will to fight, considering the Chinese threat has been a persistent issue to which many have grown desensitized but not oblivious.

Acknowledgements

The author would like to extend her gratitude to Professor Jeffrey Jacobs for his guidance and support, without which this project would not have been possible.

About the Author

Sherry Hsiao is a Master of Public Policy student at Georgetown University. Since 2025, she is also a Policy Fellow at the consultancy Safe Spaces.

References

China Power Team. “Tracking the Fourth Taiwan Strait Crisis” China Power. August 5, 2022. Updated November 8, 2023. Accessed November 18, 2025. https://chinapower.csis.org/tracking-the-fourth-taiwan-strait-crisis/

Gerald C. Brown, Benjamin Lewis, Taiwan ADIZ Violations, PLATracker, Taiwan ADIZ Violations Tracker, 2024, https://docs.google.com/spreadsheets/d/1qbfYF0VgDBJoFZN5elpZwNTiKZ4nvCUcs5a7oYwm52g/edit?usp=sharing

Shattuck, T. J., & Lewis, B. (2024, October 9). Breaking the Barrier: Four Years of PRC Military Activity Around Taiwan. Foreign Policy Research Institute. https://www.fpri.org/article/2024/10/breaking-the-barrier-four-years-of-prc-military-activity-around-taiwan/