Energetic Particle Data From the Global Positioning System Constellation

Abstract

Since 2000, Los Alamos National Laboratory (LANL) Combined X‐ray and Dosimeter (CXD) and Burst Detector Dosimeter for Block II‐R (BDD‐IIR) instruments have been fielded on Global Positioning System (GPS) satellites. Today, 21 of the 31 operational GPS satellites are equipped with a CXD detector and a further 2 carry a BDD‐IIR. Each of these instruments measures a wide range of energetic electrons and protons. These data have now been publicly released under the terms of the Executive Order for Coordinating Efforts to Prepare the Nation for Space Weather Events. The specific goal of releasing space weather data from the GPS satellites is to enable broad scientific community engagement in enhancing space weather model validation and improvements in space weather forecasting and situational awareness. The time period covered by this data release is approximately 16 years, which corresponds to more than 167 satellite years of data. The large number of GPS satellites, distributed over six orbital planes, will provide important context for ongoing and historical science missions, as well as enabling new types of research not previously possible.

Cross Calibration of the GPS Constellation CXD Proton Data With GOES EPS

“… Note . Modified from Morley et al (). GPS = Global Positioning System; CXD= Combined X‐ray Dosimeter; SVN = space vehicle number.…”

“…While there have been (and continue to be) many missions that monitor the near‐Earth energetic particle fluxes, the ability to combine measurements reliably is hampered by a lack of crossover in operations and energy coverage. With the release of Global Positioning System (GPS) energetic particle data to the general public (Executive Order 13744, ; Morley et al, ) there is now more than 187 years of satellite data available dating back to 2001 with more being collected every day. This data set encompasses an entire solar cycle and provides measurements across a broad range of energies and latitudes, including regions previously not well sampled (e.g., Adriani et al, ; Crosby et al, ; Leske et al, ).…”

“…Red bars indicate Combined X‐ray Dosimeter coverage, magenta represents Geostationary Operational Environmental Satellite Energetic Particle Sensor (GOES EPS) coverage, and blue shows the National Aeronautics and Space Administration Van Allen probes. Modified from Figure 1 of Morley et al ().…”

Measures of Model Performance Based On the Log Accuracy Ratio

“…Although the variability in electron fluxes at a given location and energy can be large (e.g., Friedel et al, 2002;Selesnick & Blake, 1997), scale-dependent measures could still be appropriate. However, there can be several orders of magnitude difference between electron fluxes at L ≃ 4 and geosynchronous orbit, with each location displaying different levels of variability (e.g., Li et al, 2005;Morley et al, 2017;Reeves et al, 2011). Thus, comparing scale-dependent accuracy measures can be problematic.…”

Maintaining a Strong Signal and Strong Impact

“…As noted in Lanzerotti (), “The papers in Space Weather attempt to build bridges between the science of space research and the applications of this research.” To that end SWE has a healthy component (~20%) of feature, commentary and news article that keep readers informed about the hot topics in the space weather discipline and inform policy makers. During the last year SWE manuscripts have ranged from the details of radiation‐measuring platforms in the atmosphere (Aplin et al, ) and at the International Space Station (Dachev et al, ), to a review of heliospheric imaging (Harrison et al, ), to scintillation of interplanetary spacecraft signals (Molera Calvés et al, ) to description and release of a decade‐plus of in situ particle data from Global Positioning System satellites (Morley et al, ).…”