Monitored U.S. Volcanoes

This dataset shows the status of all volcanoes tracked by the USGS Volcano Hazards Program. As incidents occur, volcano status will be updated to reflect the latest watch, warning, or advisory for each tracked volcano from the USGS National Volcano Early Warning System (NVEWS) program. For more details, see: Volcano Hazards Program The data provided in this dataset is sourced from the USGS, in partnership with the Smithsonian Institution Global Volcanism Program (GVP). For more details, see: Smithsonian Institution Global Volcanism Program Dataset Summary Phenomenon Mapped: Status of all volcanoes monitored by the USGS Volcano Hazards Program. Geographic Extent: This dataset covers USGS monitored volcanoes located in the Ring of fire (Pacific RIM), and Continental U.S. Source: USGS Volcano Hazards Program Update Frequency: Events are updated daily from data provided by USGS using the Aggregated Live Feed Methodology Publication Date: March 2025 This map is provided for informational purposes and is not monitored 24/7 for accuracy and currency. Always refer to the USGS source for official guidance. Attributes Key fields were taken directly from the USGS Volcano Hazards Program api. Source: USGS Volcano Hazards Program API Symbology The USGS alert-level system for volcanic activity has two parts: ranked terms to inform people on the ground about a volcano's status, and ranked colors to inform the aviation sector about airborne ash hazards. When the volcano alert level is changed, USGS issues a Volcano Activity Notice (VAN). When the volcano color code changes, USGS issues a Volcano Observatory Notification for Aviation (VONA). : Unassigned - insufficient monitoring to make assessment. : Normal - volcano is in typical background, noneruptive state or, after a change from a higher level, volcanic activity has ceased and volcano has returned to noneruptive background state. : Advisory - volcano is exhibiting signs of elevated unrest above known background level or, after a change from a higher level, volcanic activity has decreased significantly but continues to be closely monitored for possible renewed release. : Watch - volcano is exhibiting heightened or escalating unrest with increased potential of eruption, timeframe uncertain OR eruption is underway but poses limited hazards. : Warning - hazardous eruption is imminent, underway, or suspected. For more details, see: Volcanic alert-levels characterize conditions Revisions Mar 25, 2025: Updated symbology to scale with zoom level. Questions? Please leave a comment below if you have a question about this layer, and we will get back to you as soon as possible.本数据集展示了美国地质调查局（USGS）火山灾害项目所追踪的全部火山的实时状态。当相关事件发生时，系统将更新各火山的状态，以反映美国地质调查局国家火山早期预警系统（National Volcano Early Warning System, NVEWS）针对每座受追踪火山发布的最新警戒、预警或咨询信息。 如需了解更多细节，可参阅：火山灾害项目。本数据集的数据由美国地质调查局联合史密森学会全球火山活动项目（Global Volcanism Program, GVP）共同提供，更多细节可参阅：史密森学会全球火山活动项目。 数据集摘要： 映射现象：美国地质调查局火山灾害项目所监测的全部火山的状态。 地理覆盖范围：本数据集涵盖环太平洋火山带（Ring of Fire，太平洋沿岸区域）以及美国本土境内由美国地质调查局监测的火山。 数据来源：美国地质调查局火山灾害项目 更新频率：每日基于美国地质调查局提供的聚合实时数据流方法（Aggregated Live Feed Methodology）进行更新。 发布日期：2025年3月。 本地图仅用于提供信息参考，并未全天候监测以确保其准确性与时效性。如需获取官方指导，请始终参考美国地质调查局的官方来源。 属性字段：关键字段直接取自美国地质调查局火山灾害项目应用程序编程接口（Application Programming Interface, API），数据来源：美国地质调查局火山灾害项目API。 符号体系：美国地质调查局的火山活动警戒等级体系包含两部分：一是用于向地面人员告知火山状态的分级术语，二是用于向航空业通报空中火山灰灾害的分级色标。当火山警戒等级变更时，美国地质调查局会发布《火山活动通知》（Volcano Activity Notice, VAN）；当火山色标更新时，美国地质调查局会发布《航空火山观测站通知》（Volcano Observatory Notification for Aviation, VONA）。 各警戒等级说明如下： 未分配（Unassigned）：监测数据不足，无法开展评估。 正常（Normal）：火山处于典型的背景非喷发状态，或从更高等级状态回落至喷发停止、恢复至非喷发背景状态。 咨询（Advisory）：火山表现出超出已知背景水平的异常活跃迹象；或从更高等级状态回落，火山活动已显著减弱，但仍需持续密切监测，以排查是否存在再次喷发的可能。 警戒（Watch）：火山呈现加剧或升级的异常活跃状态，喷发可能性提升，但喷发时间尚不明确；或喷发已发生，但仅构成有限灾害风险。 预警（Warning）：危险喷发即将发生、正在进行或已被疑似确认。 更多细节可参阅：火山警戒等级所表征的状态。 修订记录：2025年3月25日：更新符号体系，使其可随缩放层级自适应调整。 若您对本图层存在任何疑问，请在下方留言，我们将尽快为您解答。