Van Allen Probes Project has New Journal Publication in Space Weather

Van Allen Probes Project has New Journal Publication in Space Weather

The Van Allen Probes Project has a new journal publication accepted by Space Weather. The publication titled Defining Radiation Belt Enhancement Events Based on Probability Distributions, is authored by Geoff Reeves, LANL scientist and New Mexico Consortium affiliate, along with colleagues Elizabeth M. Vandegriff, Jonathan T. Niehof, Steven K. Morley, Gregory S. Cunningham, Michael G. Henderson and Brian A. Larsen.

Earth’s radiation belts are dynamic regions of space filled with highly energetic charged particles that are trapped by the planet’s magnetic field. The intensity of these particles can vary dramatically over time, particularly during periods of increased solar and geomagnetic activity. Understanding these changes is important because enhanced radiation belt activity can pose risks to satellites, spacecraft electronics, communications systems, and other technologies that operate in space.

Electron fluxes within the radiation belts often undergo periods of rapid enhancement followed by more gradual decay. These intervals of elevated particle activity are commonly referred to as radiation belt enhancement events and can persist for days or even weeks. Despite decades of research, however, scientists have faced challenges in establishing a standard definition for these events. Differences in measurement techniques, event magnitudes, and observational criteria have made it difficult to consistently identify and compare radiation belt enhancements across studies.

To address this challenge, Reeves and his colleagues developed a new methodology for identifying and categorizing radiation belt enhancement events. Their approach uses probability distributions to establish objective thresholds that distinguish between different levels of space weather activity.

The study introduces a framework for classifying radiation belt enhancement events as moderate, strong, or intense based on statistical analysis rather than subjective criteria. This methodology can be applied directly to measurements of relativistic electron fluxes collected by the Los Alamos National Laboratory geosynchronous satellite instruments (LANL-GEO), providing a more consistent and quantitative way to characterize space weather events.

By establishing standardized definitions, researchers can more easily compare results across different studies, improve event forecasting, and better understand the physical processes that drive changes in Earth’s radiation environment. The methodology also provides a foundation for future investigations into how radiation belt enhancements develop and evolve over time.

This work represents an important step toward improving the scientific community’s ability to monitor and characterize hazardous space weather conditions. As society becomes increasingly dependent on satellite-based technologies, a better understanding of radiation belt dynamics is essential for protecting critical infrastructure and improving space weather prediction capabilities.

To learn more about radiation belt enhancement events, their importance in space weather research, and the methodology developed in this study, readers are encouraged to explore the full publication, Defining Radiation Belt Enhancement Events Based on Probability Distributions.

Figure at top of page: This figure is taken from the paper with caption explaining: “Relativistic electron fluxes in 1994 and 2004 during the declining phases of solar cycles 22 and 23, respectively. Moderate events (100/cycle) are identified in green, strong events (10/cycle) are in blue, and intense events (1/cycle) are in red.”