#Japan #Hokkaido #Earthquake #Ionosphere #HiSR

Signs of the 2026 Tokachi Earthquake Detected by HiSR Corporation

On April 27, 2026, at approximately 5:24 AM, the Tokachi region of Hokkaido experienced a significant earthquake measuring M6.1, which recorded a maximum intensity of Shindo 5 Upper in Urakawa Town and Shindo 5 Lower in Niikappu Town. Notably, the depth of the earthquake was reported to be between 80 to 83 km, and it was not categorized under the aftershock advisory system.

Recent analysis from HiSR Corporation, a startup associated with Chiba University and led by CEO Nobuhiko Hirooka, suggests that unusual ionospheric electron density fluctuations were observed in Hokkaido and Northeast Japan two to three days prior to the earthquake. The unusual increase in total electron content (TEC) was measured at nearly a 3σ level, indicating a highly atypical occurrence. Historical data suggests that earthquakes exceeding magnitude 6 and occurring at depths of less than 40 km have a 65-70% chance of affecting ionospheric stability, thus linking the events.

Solar activity is widely recognized for causing variations in ionospheric electron levels. However, during the time leading up to the earthquake, only minor disturbances were noted following solar flare activity, suggesting no significant solar influence. The depth of the earthquake being between 80–83 km adds complexity to interpreting precursor signals, which exhibited notable spatial dispersion and ambiguity.

HiSR Corporation continues to focus on earthquake disaster prevention and mitigation strategies using AI and various geophysical data aimed at both business-to-business (BtoB) and business-to-government (BtoG) sectors. The objective is to raise awareness of our efforts amongst the public and gather continued support through our innovative work.

From April 27 to May 11, 2026, we are actively pursuing funding through equity crowdfunding for our short-term earthquake prediction endeavors. We are making significant enhancements to our current AI system, driven by the goal of pulling together resources to save even one individual from the impacts of earthquake disasters.

For more information, please check our official website: HiSR Corporation.

Additionally, we have laid out a dedicated funding page: Funding Page. For investors interested in a tailored application process, we offer a priority examination via this registration link: Investor Registration.
Special investor programs are currently being prioritized, especially for high-net-worth individuals, business executives, and corporate entities requiring an investment application of 500,000 yen or more, which can be found here: Specific Investor Program.

The provided images illustrate the daily variations in ionospheric total electron content anomalies using GPS technology. Areas marked in light blue indicate normal levels, while red highlights regions showing significant increases. The seismic data shown in the lower right was referenced from the Japan Meteorological Agency’s website.