User Manual
Use Jishinwatch to explore recent earthquake activity in Japan, North America, Europe & Mediterranean, East & Southeast Asia, the Middle East, South America, Africa, and Australia & Oceania on a live map, replay events in sequence, inspect maximum reported intensity, and understand where shaking was reported.
Map overview
The main map shows recent earthquakes in the selected region. Larger circles generally represent larger magnitudes, while each marker color follows the magnitude color scale. Click a quake marker to hold its tooltip and show available intensity reporting points. Click elsewhere on the map to clear that held view.
Save and share a map image
Arrange the map, enable the layers you want, and select any earthquake or location tags you want to include. Select the camera icon to the left of Share in the header to open an image preview. The capture includes the current map view, visible map layers and tags, with Jishinwatch branding, a capture timestamp and data attribution; navigation controls and menus are left out. Animated layers are captured as a still image, not a video. Check the preview, then choose Save Image to download it, Share Image to open your device’s sharing options when supported, or Close to return to the map. On phones the preview adapts to the available screen height. Share Image appears only when the browser supports file sharing, normally on HTTPS; it may be absent during local-network HTTP testing. Save Image remains available. Review any personal location tags before sharing. Unlike a shared map link, an image is a fixed snapshot and does not update with new data.
Sharing
Use the header or event Share button to copy the current region and map view, including the selected earthquake when present. See Sharing your region above.
Settings
Use Settings to change language, refresh cycle, map style, and access the User Manual, FAQ, and About pages. View preferences are stored locally so a browser refresh can keep the map experience consistent.
South America coverage
Select South America in Settings to load the past 30 days of USGS earthquake reports within 60°S–15°N and 95°W–25°W. This includes Chile, Peru, the Andes and a broad offshore margin, as well as nearby border areas. The regional window is not a country boundary. Location names are currently English-only and times remain JST. Sharing uses region=sa. Japan-only weather and tsunami features remain hidden; earthquake selection, playback and location tools work as in the other non-Japan regions.
Africa and Australia & Oceania
Africa covers 40°S–38°N, 25°W–65°E, including Madagascar and nearby waters. Australia & Oceania covers 55°S–30°N, from 110°E eastward across the date line to 120°W, including New Zealand and Pacific islands. Both use the past 30 days of USGS reports; smaller earthquakes may be missing. These broad windows overlap neighboring regions. Names are English-only, times are JST, and Japan-only weather and tsunami features remain hidden. Shared URLs use region=af and region=oc.
Middle East coverage
Choose Middle East in Settings for EMSC earthquake data covering 12–43°N and 25–65°E: Türkiye, the Levant, the Arabian Peninsula, Iraq, Iran, and nearby waters and border areas. This view uses the past 30 days of available reports, without merging feeds. Location names remain in English and times are shown in JST. The earthquake list, timeline, location tools, and sharing work as in other regions; Japan-only features remain hidden. Regional boundaries intentionally overlap Europe & Mediterranean.
Region and data sources
In Settings, choose Japan, North America, Europe & Mediterranean, East & Southeast Asia, Middle East, South America, Africa, or Australia & Oceania independently of the interface language. Europe & Mediterranean uses the EMSC catalogue (25–72°N, 25°W–45°E, including nearby offshore areas). East & Southeast Asia uses USGS within 12°S–55°N, 73–150°E, including Japan, Vietnam, the Philippines, and nearby offshore and border areas. It does not merge feeds; the separate Japan view may show smaller events absent from USGS. East & Southeast Asia location names remain in English. Each non-Japan feed covers the past 30 days. Coverage of smaller earthquakes varies by country. The app loads separate earthquake datasets rather than merging them: Japan uses the P2PQuake API; the North America view uses the USGS GeoJSON feed. North America coverage includes Canada, the United States, Mexico, Central America, the Caribbean, Alaska, Hawaii, and nearby waters. Boundaries are broad geographic windows, not country borders. Times remain Japan Standard Time (JST) in every region.
North America quick views
Overview, Alaska, and Hawaii buttons reposition and zoom the map without filtering the earthquake list or timeline or changing the selected earthquake. On desktop they sit below the previous/next event controls; they are hidden on phones. These shortcuts are exclusive to the North America view.
Regional features and location names
When any non-Japan region is selected, earthquake marker location names are currently available only in English, even with the Japanese interface. North American event details link to the original USGS report; Japanese shindo and tsunami-status fields are not displayed. Japan-only typhoon, radar, lightning, wind, five-day forecast, and Weather timeline controls are hidden in every non-Japan region. North America, East & Southeast Asia, South America, Africa, and Australia & Oceania reports link to USGS; Europe & Mediterranean and Middle East reports link to EMSC. Returning to Japan restores its controls and saved layer/timeline choices. Automatic JMA tsunami coastlines are available only in Japan mode.
Sharing your region
Header and event share links include the region, map style, zoom, map center, supported weather-layer states, and selected earthquake when present. The shared map position takes priority over centering on the selected earthquake. Region selection is also remembered in this browser.
Timeline replay
The timeline plays the currently displayed earthquakes in the order they occurred. Use play to start, stop to end playback, and loop to continuously replay the sequence. The timeline settings menu includes Show Info and playback speed controls.
Show or hide earthquakes
Earthquakes are visible by default on each page load. On desktop, the top control with concentric circles toggles the earthquake layer. On phones, Earthquakes is the first item in the Layers menu; the eye indicates whether it is visible. Hiding earthquakes removes their circles, details tags, magnitude labels, reporting points, and the location measurement line from the map, but leaves the event list available. Turn the layer on again or click an event in the list to restore it; selecting a list event also focuses that earthquake. Background refreshes continue but do not restore hidden earthquakes or move the map to new events.
Earthquake list
The list can show recent earthquakes by time window or by latest event count. Use the selector to choose ranges such as the last hour or the latest five events. Sort the table by magnitude, date and time, or depth. Click a row to expand extra details, including coordinates, tsunami status, and maximum reported intensity.
Viewing a single earthquake
Open the earthquake list and click an event row to center the map on that quake. The map opens the event tooltip, displays the quake details, and shows available intensity reporting stations.
Refreshing data
The refresh button checks for new earthquake data immediately. Settings also include a refresh cycle selector so the app can check automatically. When the feed refreshes, current filters and ordering remain applied to the new data set.
Your location
The location button requests browser location permission and shows your position as a blue dot. It measures the approximate distance to the latest earthquake in the displayed dataset, not the nearest earthquake, with a green connecting line. Selecting another earthquake updates the distance and line. Click empty map space to turn measurement off; dragging preserves it. The acquired position is reused in memory until you refresh or close the page. While locating, “Locating Your Position” stays visible. Temporary failures retry for up to 30 seconds; permission denial stops immediately. If unsuccessful, check location permissions and try again later. Mobile location access generally requires HTTPS. The last successful coordinates are also saved locally in browser settings; clear site data to remove them. Review location tags before sharing links or images.
Magnitude key
The magnitude key explains the marker color scale. Magnitude is the size of the earthquake at its source, so it is different from how strongly shaking was felt at each reporting location.
Tectonic overlays
The layers button lets you choose plate boundaries and major trenches. When an overlay is enabled, a matching key appears to explain the displayed line styles. These layers are useful for learning how recent earthquakes relate to nearby tectonic features.
Typhoon overlay
The tornado button toggles current JMA typhoon data when available. The red dot shows the current storm center, dotted lines connect projected forecast centers, forecast circles show possible future position areas, and the key includes the JMA issue time in JST.
Weather radar
The cloud rain button toggles current JMA weather radar data. When radar is enabled, the radar timeline can replay recent and near-future radar frames, and the radar slider adjusts the precipitation layer transparency. This layer is for quick visual reference only; always use official JMA information for weather warnings and decisions.
5 Day Forecast
With Japan selected, enable Weather Radar, then select “5 Day Forecast” beneath the radar transparency slider. Location permission is requested when you first open the forecast, not when you enable radar. Allow access to show the next five days, starting tomorrow, for the JMA forecast area containing your current location. The panel slides beneath the header, covering the timeline and its toggle. It shows daily weather icons, high and low temperatures in °C, and rain probability; a dash means a value is unavailable. Yellow suns, white clouds, and light-blue rain indicate the forecast conditions. This is a regional forecast, with temperatures from a representative station, not a precise forecast for your street. The map centers on a blue location dot without changing zoom, and its tag confirms that the forecast is for your current location. Select the button again to close the panel and remove the forecast marker; turning radar off also closes it. If location access or forecast data is unavailable, follow the message and use Retry. Phone location access requires HTTPS. Forecasts are available within Japan only. Use the area’s JMA link for official forecast details.
Lightning activity
Use the lightning bolt button on desktop, or choose Lightning in the Layers menu on mobile, to toggle JMA lightning activity. Enabling this layer switches the timeline to Weather. Play, stop, loop, or drag the playhead to explore available frames from one hour before to one hour after the current observation time. Future frames are forecasts, not observed strikes. White lightning symbols with black outlines represent activity areas, not exact individual strike locations; they flash twice when a frame is displayed. There is no separate lightning key. If data is unavailable or the loaded frame contains no activity symbols, a notice appears on the map. Use official JMA information for warnings and safety decisions.
Wind
With Japan selected, use the Wind button below Lightning on desktop, or select Wind below Lightning in the mobile Layers menu. Toggling Wind leaves the timeline mode unchanged. Turning off both Radar and Lightning switches the timeline back to Earthquakes, even if Wind remains on. Moving particles illustrate interpolated forecast wind at 10 metres above ground from Open-Meteo, not live measurements; their screen speed is illustrative, not a precise speed scale. Movement continues while you pan the map. Wind can be shown alone or alongside radar and lightning, and the Weather timeline updates all enabled weather layers together. Play, stop, loop, or drag the playhead across the available one-hour-before to one-hour-after window. Stopping timeline playback holds the selected forecast time while wind particles continue moving. The collapsible Wind Key shows the forecast time in JST and attribution; on phones it starts closed. Wind is header-green on the Standard map and light-colored on other styles. Shared links include whether Wind is enabled. Coverage extends around Japan and nearby waters, but is not worldwide. When typhoon data is loaded, finer wind sampling around up to three active typhoons blends into the wider field; the key also shows their position times. Model differences, sampling and different timestamps can leave the wind circulation offset from JMA typhoon centers. Use official forecasts and warnings for safety decisions.
Zoom controls
Use the plus and minus buttons on the right side of the map to zoom in or out in smaller steps. These controls mirror the map interaction without requiring trackpad or mouse wheel gestures.
Tsunami warnings
Affected coastlines are highlighted automatically when active JMA tsunami warnings or advisories are available; there is no show/hide layer button. Yellow means a tsunami advisory, red means a tsunami warning, and purple means a major tsunami warning, from weakest to strongest. The outlines follow JMA coastal forecast areas, which may cover only part of a prefecture. Hover over a highlighted coastline, or tap it on a touch device, to see the warning level and expected tsunami height supplied by JMA. Heights may be given as numbers or as “High” or “Huge”; they are not inland inundation depths. The app checks for updates every minute while visible and when you return to it. Historical earthquake entries do not activate these warnings. If updates fail, the app shows an unavailable/out-of-date notice. This display is not an emergency alert service: check official JMA and local authority information and follow evacuation instructions.
Jishinwatch is an educational tool. For official warnings, advisories, evacuation information, and emergency guidance, always refer to the Japan Meteorological Agency and local authorities.