Strong Geomagnetic Storms Research Articles

Magnetic Field Evolution of the Solar Active Region 13664

On 2024 May 10–11, the strongest geomagnetic storm since 2003 November occurred, with a peak Dst index of −412 nT. The storm was caused by NOAA active region (AR) 13664, which was the source of a large number of coronal mass ejections and flares, including 12 X-class flares. Starting from about May 7, AR 13664 showed a steep increase in its size and (free) magnetic energy, along with increased flare activity. In this study, we perform 3D magnetic field extrapolations with the NF2 nonlinear force-free code based on physics-informed neural networks (R. Jarolim et al.). In addition, we introduce the computation of the vector potential to achieve divergence-free solutions. We extrapolate vector magnetograms from the Solar Dynamics Observatory’s Helioseismic and Magnetic Imager at the full 12 minute cadence from 2024 May 5 00:00 to 11 04:36 UT, in order to understand the AR’s magnetic evolution and the large eruptions it produced. A decrease in the calculated relative free magnetic energy can be related to solar flares in ∼90% of the cases, and all considered X-class flares are reflected by a decrease in the relative free magnetic energy. Regions of enhanced free magnetic energy and depleted magnetic energy between the start and end times of major X-class flares show spatial alignment with brightness increases in extreme-ultraviolet observations. We provide a detailed analysis of the X3.9-class flare on May 10, where we show that the interaction between separated magnetic domains is directly linked to major flaring events. With this study, we provide a comprehensive data set of the magnetic evolution of AR 13664 and make it publicly available for further analysis.

Prediction of geomagnetic storms associated with interplanetary coronal mass ejections

Geomagnetic storms have a significant impact on the performance of technical systems both in space and on Earth. The sources of strong geomagnetic storms are most often interplanetary coronal mass ejections (ICMEs), generated by coronal mass ejections (CMEs) in the solar corona. The ICME forecast is based on regular optical observations of the Sun, which make it possible to detect CMEs at the formation stage. It is known that the intensity of geomagnetic storms correlates with the magnitude of the southern component of the magnetic field (Bz) of the ICME. However, it is not possible yet to predict the sign and magnitude ofBzfrom solar observations for the operational forecast of an arbitrary CME. Under these conditions, a preliminary forecast of the magnetic storm probability can be obtained under the assumption that the strength of the storm is related to the magnitude of the magnetic flux from the eruption region, observed as dimming. In this paper we examine the relationship between the integral magnetic flux from the dimming region and the probability that CMEs associated with them will cause geomagnetic storms, using a series of 37 eruptive events in 2010–2012. It is shown that there is a general trend toward an increase in the ICMEs geoefficiency with an increase in the magnitude of the magnetic flux from the dimming region. It has been demonstrated that the frequency of moderate and severe storms observation increases in cases of complex events associated with the interaction of CMEs with other solar wind streams in the heliosphere.

Investigating the 17 March 2013 Geomagnetic Storm Impacts on the Wholly Coupled Solar Wind‐Magnetosphere‐Ionosphere‐Thermosphere System‐Of‐Systems

AbstractIn this study, we investigate the impacts of the 17 March 2013 strong geomagnetic storm on the wholly coupled Solar Wind‐Magnetosphere‐Ionosphere‐Thermosphere system‐of‐systems. Obtained from multipoint observations, our new results show (1) the solar‐wind Alfven waves propagating antisunward in the sheath region and (2) oscillating solar wind interplanetary magnetic field (IMF) and electric (E) field (IEF EY) that powered (3) rigorous dayside and nightside flux transfer events (FTEs) when (4) the nightside‐reconnection‐related short circuiting led to fast‐time Subauroral Ion Drifts (SAID) and Subauroral Polarization Streams (SAPS) E field development across the inner‐magnetosphere plasmapause where the solar‐wind Alfven waves (4) transitioned into kinetic Alfven waves (5) fueling the hot zone. Also, the antisunward solar‐wind Alfven waves (6) drove enhanced large‐scale region‐1 field‐aligned currents creating (7) undershielding conditions (8) allowing the dawn‐to‐dusk convection E field's earthward penetration, and (9) generated increased solar‐wind kinetic energy, which became deposited (10) to the ionosphere increasing the ionospheric electron temperature (by the downward flowing suprathermal electron fluxes) and (11) to the thermosphere oscillating the neutral winds and increasing the neutral temperature, and finally leading to (12) the development of bright stable auroral red (SAR) arcs in (13) the enhanced SAID/SAPS flow channels (FCs) developed during FTEs, (14) demonstrated with FC‐2 and FC‐3 events, in the enhanced polar convection that (15) the Rice Convection Model could reproduce. Finally, we conclude the antisunward‐propagating large‐amplitude solar‐wind Alfven waves' ultimate significant role in creating the favorable conditions for the various phenomena documented with the new observational results (1–14).

Parameter Study of Geoeffective Active Regions

Geomagnetic storms (GSs) are major disturbances in the terrestrial atmosphere caused by the reconnection process between the incoming plasma ejecta in the solar wind and the planetary magnetosphere. The strongest GSs can lead to auroral displays even at lower latitudes, and cause both satellite and ground-based infrastructure malfunctions. The early recognition of geoeffective events based on specific features on the solar photosphere is crucial for the development of early warning systems. In this study, we explore 16 magnetic field parameters provided by the Space-weather HMI Active Region Patch (SHARP) database from the SDO/HMI instrument. The analysis includes 64 active regions that produced strong GS during solar cycle (SC) 24 and the ongoing SC25. We present the statistical results between the SHARP and solar parameters, in terms of Pearson and Spearman correlation coefficients, and discuss their space weather potential.

Establishment and Application of an Interplanetary Disturbance Index Based on the Solar Wind–Magnetosphere Energy Coupling Function and the Spectral Whitening Method

We develop a preliminary interplanetary disturbance index (J sW ) by applying the spectral whitening method to an energy coupling function with solar wind measurements during the years 1998–2014 as the input, which can be used as an indicator of perturbations in the near-Earth solar wind. The correlation and temporal variation between J sW and the geomagnetic disturbance index (J pG ) constructed from the same method have been analyzed in detail for 167 geomagnetic storms with the minimum D st index less than or equal to −50 nT. The time delay between J sW and J pG is clearly observable and varies for different events, according to which J sW is shifted backward with respect to J pG . We obtain a fairly good negative correlation between the shifted J sW and the J pG indices for the majority of events, and the significance level for 88% of the events (i.e., 147 events) does not exceed 0.05. A statistical analysis of the shifted J sW and the J pG indices for 147 selected events reveals that larger values of J sW and smaller magnitudes of J pG are commonly accompanied by enhanced southward magnetic fields, which implies that more solar wind energy is entering the magnetosphere and thus causing strong geomagnetic storms. Furthermore, a linear fit of the two indices suggests that the evolution of J pG can be predicted about 2 hr in advance based on J sW , indicating that J sW can provide early warnings of possible disturbances in the geomagnetic fields, which is crucial for space weather monitoring and operational forecasting.

New Anisotropic Cosmic-Ray Enhancement (ACRE) Event on 5 November 2023 Due to Complex Heliospheric Conditions

The variability of galactic cosmic rays near Earth is nearly isotropic and driven by large-scale heliospheric modulation but rarely can very local anisotropic events be observed in low-energy cosmic rays. These anisotropic cosmic-ray enhancement (ACRE) events are related to interplanetary transients. Until now, two such events have been known. Here, we report the discovery of the third ACRE event observed as an increase of up to 6.4% in count rates of high- and midlatitude neutron monitors between ca. 09 – 14 UT on 5 November 2023 followed by a moderate Forbush decrease and a strong geomagnetic storm. This is the first known observation of ACRE in the midrigidity range of up to 8 GV. The anisotropy axis of ACRE was in the nearly anti-Sun direction. Modeling of the geomagnetic conditions implies that the observed increase was not caused by a storm-induced weakening of the geomagnetic shielding. As suggested by a detailed analysis and qualitative modeling using the EUHFORIA model, the ACRE event was likely produced by the scattering of cosmic rays on an intense interplanetary flux rope propagating north of the Earth and causing a glancing encounter. The forthcoming Forbush decrease was caused by an interplanetary coronal mass ejection that hit Earth centrally. A comprehensive analysis of the ACRE and complex heliospheric conditions is presented. However, a full quantitative modeling of such a complex event is not possible even with the most advanced models and calls for further developments.

Dynamics and solar wind control of the recovery of strong geomagnetic storms

Dynamics and solar wind control of the recovery of strong geomagnetic storms

A Statistical Analysis of the Morphology of Storm‐Enhanced Density Plumes Over the North American Sector

AbstractThe storm‐enhanced density (SED) is a large‐scale midlatitude ionospheric electron density enhancement in the local afternoon sector, which exhibits substantial spatial gradients and thus can impose detrimental effects on modern navigation and communication systems, causing potential space weather hazards. This study has identified a comprehensive list of 49 SED events over the continental US and adjacent regions, by examining strong geomagnetic storms occurring between 2000 and 2023. The ground‐based Global Navigation Satellite System (GNSS) total electron content and data from a new TEC‐based ionospheric data assimilation system were used to analyze the characteristics of SED. For each derived SED events, we have quantified its morphology by employing a Gaussian function to parameterize key characteristics of the SED, such as the plume intensity, central longitude, and half‐width. A statistical analysis of SEDs was conducted for the first time to characterize their climatological features. We found that the SED distribution exhibits a higher peak intensity and a narrower width as geomagnetic activity strengthens. The peak intensity of SED has maximum values around the equinoxes in their seasonal distribution. Additionally, we observed a solar cycle dependence in the SED distribution, with more events occurring during the solar maximum and declining phases compared to the solar minimum. SED plumes exhibit a sub‐corotation feature with respect to the Earth, characterized by a westward drift speed between 50 and 400 m/s and a duration of 3–10 hr. These information advanced the current understanding of the spatial‐temporal variation of SED characteristics.

3‐D Ionospheric Imaging Over the South American Region With a New TEC‐Based Ionospheric Data Assimilation System (TIDAS‐SA)

AbstractThis study has developed a new TEC‐based ionospheric data assimilation system for 3‐D regional ionospheric imaging over the South American sector (TIDAS‐SA) (45°S–15°N, 35°–85°W, and 100–800 km). The TIDAS‐SA data assimilation system utilizes a hybrid Ensemble‐Variational approach to incorporate a diverse set of ionospheric data sources, including dense ground‐based Global Navigation Satellite System (GNSS) line‐of‐sight Total Electron Content (TEC) data, radio occultation data from the Constellation Observing System for Meteorology, Ionosphere, and Climate‐2 (COSMIC‐2), and altimeter TEC data from the JASON‐3 satellite. TIDAS‐SA can produce a reanalyzed three‐dimensional (3‐D) electron density spatial variation with a high time cadence, yielding spatial‐temporal resolution of 1° (latitude) × 1° (longitude) × 20 km (altitude) × 5 min. This allows us to reconstruct and study the 3‐D ionospheric morphology with multi‐scale structures. The performance of the data assimilation system is validated against independent ionosonde and in situ measurements through an experiment for a strong geomagnetic storm event on 03–04 November 2021. The results demonstrate that TIDAS‐SA can provide detailed and altitude‐resolved information that accurately characterizes the storm‐time ionospheric disturbances in vertical and horizontal domains over the equatorial and low‐latitude regions of South America.

Investigating the heliosphere, magnetosphere, atmosphere, and properties of cosmic rays during the 2018 Aug 25–26 strong geomagnetic storm

We investigated the conditions of the heliosphere, magnetosphere, and atmosphere from cosmic ray (CR) observations during the 2018 Aug 25–26 strong geomagnetic storm. The analysis involved the global survey (GS) and the spectrographic global survey (SGS) methods created and developed at the Yu.G. Shafer Institute of Cosmophysical Research and Aeronomy of the Siberian Branch of the Russian Academy of Sciences (ShICRA SB RAS) and at the Institute of Solar-Terrestrial Physics of the Siberian Branch of the Russian Academy of Sciences (ISTP SB RAS). Also, in our analysis, we used the data on direct measurements of the interplanetary medium parameters from the known OMNI database, CR measurements at the GOES geostationary satellites, from the global network of neutron monitors and muon detectors, from the Sayan spectrograph, and from the A.I. Kuzmin Yakutsk spectrograph of CR. When analyzing this event, the SGS enabled to obtain the data on the orientation of the mean interplanetary magnetic field, on the geomagnetic cutoff rigidity and its variations during the geomagnetic storm. Also, this method allowed us to estimate the bulk temperature over the point of recording CR, the ring current and the magnetopause current, as well as their contributions to the Dst-index, and also to establish differential rigidity spectra of CR at different stages of the magnetic storm evolution. Through the GS method, we determined the value and the directions for the first two spherical harmonics of CR distribution, and the direction to their anisotropy source. The results obtained through two different global survey methods are shown to be agree and mutually supplement each other. Using the Yakutsk spectrograph records enabled to determine the index for the power energy spectrum of variations in CR intensity during the investigated event.

ON THE DELAY OF THE ADDITIONAL MORTALITY LINKED TO THE GEOMAGNETIC DISTURBANCES

The geomagnetic disturbances, mainly geomagnetic storms (GMSs), but also low frequency resonances, touch some people susceptible to cerebrovascular diseases (CVDs). Sometimes the geomagnetic effect is overestimating speculatively. Against this concept we compare the changes of geomagnetic indexes (GMIs) with the changes of additional mortality rate (AMR). We compare by means of cross-correlation functions (CCFs) and use the Wolf number (WN) as referent time scale. We suspect that strong GMSs, like these in 2003, increase the relative common MR 3–4 years later with up to 4×10-5. Otherwise, the typical GMS linked AMR seems to be less than 10-5. Even if these values are overestimated, generally they are small. Analyzing data about Bulgaria and 5 its regions for the last solar cycles, we confirm that the lag of the maxima of the GMS linked ANR behind the WN maxima is ~5 years. We confirm also that the lag of the GMSs maxima behind the WN maximum is 1–2 years. Especially, we found that the lag of the maxima of the CVD linked AMR behind the maxima of the GMSs is 3–4 years. So, we consider the 5 years lag of the AMR linked to the GMSs behind the WN maximum appears a sum of two above mentioned delays, 1–2 years and 3–4 years. In principle, the typical duration of CVDs may be derived if the beginnings are known. In the medicine they are usually unknown. However, suspecting the GMSs as triggers of a part of the CWD linked AMR, we should suppose that these CWDs finish with lethal outcome after 3–4 years.

Changes in the energy density of the Earth's magnetic field at the PIA, Slovenia, observatory during the G5 Geomagnetic Storm on May 11, 2024

Geomagnetic storms are the largest disturbance in the Earth's magnetic field. On May 11, 2024, a geomagnetic storm occurred at the peak of the 25th solar cycle, reaching the highest level (G5) on the planetary scale. On that day, a geomagnetic storm was also measured at the PIA geomagnetic observatory (Piran, Slovenia), reaching the maximum possible value of the geomagnetic index K = 9. Such strong geomagnetic storms occur on average every 40 to 60 years. A geomagnetic storm with an index of K = 9 represents an important reference for all disturbances in the local magnetic field from different sources and different intensities. Therefore, an analysis of accelerations in the energy density of the local magnetic field during the first 150 days in 2024 was made. The identified effects of geomagnetic storms with different K indices will serve to better analyse disturbances in the local magnetic field that have occurred in the past years and will happen in the future.

Ground and Space-based response of the ionosphere during the geomagnetic storm of 02–06 November 2021 over the low-latitudes across different longitudes

The strong geomagnetic storm of class G3 that occurred on 03 November 2021 (Dst min = −118 nT, Kp = 8) was the first of this class recorded during the ascending phase of solar cycle 25. In this study, we examined the response of the ionosphere during the geomagnetic storm period from 02–06 November 2021 using the Total Electron Content (TEC) observations from a chain of Global Navigation Satellite System (GNSS) receiver stations in five longitudinal sectors i.e, Asian, East-African, West-African, South-American, and Pacific-west sectors, in the low-latitudes and space-based Swarm satellite electron density, Ne and TEC measurements. The Rate of Change of TEC Index (ROTI) was derived from the ground and space based TEC measurements to examine the occurrence of ionospheric irregularities. The Rate of change of electron density index (RODI) was also derived from Swarm Ne measurements to identify the occurrence of ionospheric irregularities at Swarm altitudes. A positive ionospheric storm effect was observed in all the longitudinal sectors considered in this study. A clear hemispherical asymmetry, with higher VTEC in the northern hemisphere was observed. The determining factors for ionospheric responses to this storm are; local time of the storm’s onset, local time of storm’s minimum SYM-H, and changes in thermospheric O/N2 ratio. These geomagnetic storm effects were discussed in terms of the Prompt Penetration Electric Field (PPEF) storm induced wind lifting effect and Disturbance Dynamo Electric Field (DDEF). The geomagnetic storm inhibited the occurrence of ionospheric irregularities in all the sectors, during the main phase, except for three IGS receiver stations in South American sector. Overall, a longitudinal dependence of the enhancement/inhibition of ionospheric irregularities was observed. The generation of post-sunset irregularities was attributed to the local time occurrence of maximum ring current, PPEF and DDEF.

Ionospheric response characteristics and PPP accuracy analysis at different latitudes during strong geomagnetic storms

Ionospheric response characteristics and PPP accuracy analysis at different latitudes during strong geomagnetic storms

Automatic sunspot detection through semantic and instance segmentation approaches

The solar influence on space weather and terrestrial environment is substantial. Strong geomagnetic storm activity can significantly affect astronauts in orbit, communications and GPS systems and disrupt Earth’s power distribution networks, making continuous monitoring and forecasting of solar activity vital. Sunspots are magnetic disturbances in the photosphere characterized by their dark appearance in the solar disk, being directly related to phenomena that contribute to these intense storms, namely solar flares and coronal mass ejections. This article lies at the intersection between solar surveillance and computer vision by applying state-of-the-art deep learning algorithms in the automatic detection of sunspots and sunspot groups. Based on two techniques, semantic segmentation and instance segmentation, two algorithms are implemented to tackle both purposes, U-Net and Mask R-CNN respectively. The ground-truth dataset was built from the available Debrecen Heliographic Observatory (DHO) space-borne sunspot catalogues from 2010 to 2014. The best U-Net implemented model presented a 74.2% IoU, surpassing the detection results evidenced by the Automated Solar Activity Prediction System (ASAP). The instance segmentation approach, a novelty application technique for sunspot group detection and still a challenging task in computer vision, achieved 51.7 bounding box AP and 78.6% accuracy in predicting the number of sunspot groups.

Effects of Strong Geomagnetic Storms on the Ionosphere and Degradation of Precise Point Positioning Accuracy during the 25th Solar Cycle Rising Phase: A Case Study

Approaching the peak year of the 25th solar activity cycle, the frequency of strong geomagnetic storms is gradually increasing, which seriously affects the navigation and positioning performance of GNSS. Based on the globally distributed GNSS station data and FORMOSAT-7/COSMIC-2 occultation data, this paper explores for the first time the effects of the G4-class geomagnetic storm that occurred on 23–24 April 2023 on the global ionosphere, especially the ionospheric equatorial anomalies and F-layer perturbations. It reveals the precise point positioning (PPP) accuracy degradation during a geomagnetic storm. The results show that the ionospheric rate of total electron content index (ROTI) and near high latitude GNSS phase scintillations index have varying levels of perturbation during geomagnetic storms, with the maximum ROTI and phase scintillations index exceeding 0.5 TECU/min and 0.8, respectively. The equatorial ionization anomaly (EIA) shows an enhanced state (positive ionospheric storms) during geomagnetic storms, and the cause of this phenomenon is most likely the equatorward neutral wind. The variation of the S4 index of the FORMOSAT-7/COSMIC-2 satellite reveals the uplift of the F-layer during geomagnetic storms. During geomagnetic storms, the PPP accuracy degrades most seriously at high latitudes, the maximum MAE exceeds 2.3 m, and the RMS in the three-dimensional (3D) direction exceeds 2.0 m. These investigations can provide case support for space weather and GNSS studies of the impact of geomagnetic storms during peak solar activity years.

Large regional variability in geomagnetic storm effects in the auroral zone

A digital society is fragile and vulnerable to space-originated electromagnetic disturbances. Global geomagnetic conditions have been actively monitored since the invention of the magnetometer in 1833. However, regional changes in the magnetic environment have been widely left unstudied because of the sparsity of the observing networks. The Scandinavian Magnetometer Array (SMA) was the densest magnetometer network in history, and it was in operation in Fennoscandia during the International Magnetospheric Study (IMS) in 1976–1979. The data has been left mainly unstudied because it was recorded on 35 mm films, which are difficult to use for scientific studies. We used the DigiMAG digitization method to digitize magnetic data from all 32 SMA stations for a geomagnetic storm on 10–12 December 1977. Using these digitized values and modern magnetic data, we found large regional differences about up to 2 nT/km during strong geomagnetic storms (Dst 100–200 nT) and 7 nT/km for major scale Halloween geomagnetic storm, which correspond to 400 and 1400 nT difference for a typical 200 km station separation, respectively. The average size of substorms is 400 nT in the auroral zone. We conclude that the sparse magnetometer network can cause an underestimation of the regional magnetic disturbances and their effects. Misestimation of regional disturbances during extreme storms like the Carrington event may lead to insufficient planning of mitigation procedures and strategies.

The Contribution of Plasma Sheet Bubbles to Stormtime Ring Current Buildup and Evolution of Its Energy Composition

AbstractThe formation of the stormtime ring current is a result of the inward transport and energization of plasma sheet ions. Previous studies have demonstrated that a significant fraction of the total inward plasma sheet transport takes place in the form of bursty bulk flows, known theoretically as flux tube entropy‐depleted “bubbles.” However, it remains an open question to what extent bubbles contribute to the buildup of the stormtime ring current. Using the Multiscale Atmosphere Geospace Environment Model, we present a case study of the 17 March 2013 storm, including a quantitative analysis of the contribution of plasma transported by bubbles to the ring current. We show that bubbles are responsible for at least 50% of the plasma energy enhancement within 6 RE during this strong geomagnetic storm. The bubbles that penetrate within 6 RE transport energy primarily in the form of enthalpy flux, followed by Poynting flux and relatively little as bulk kinetic flux. Return flows can transport outwards a significant fraction of the plasma energy being transported by inward flows, and therefore must be considered when quantifying the net contribution of bubbles to the energy buildup. Data‐model comparison with proton intensities observed by the Van Allen Probes show that the model accurately reproduces both the bulk and spectral properties of the stormtime ring current. The evolution of the ring current energy spectra throughout the modeled storm is driven by both inward transport of an evolving plasma sheet population and by charge exchange with Earth's geocorona.

Trailing Equatorial Plasma Bubble Occurrences at a Low-Latitude Location through Multi-GNSS Slant TEC Depletions during the Strong Geomagnetic Storms in the Ascending Phase of the 25th Solar Cycle

The equatorial plasma bubbles (EPBs) are depleted plasma density regions in the ionosphere occurring during the post-sunset hours, associated with the signal fading and scintillation signatures in the trans-ionospheric radio signals. Severe scintillations may critically affect the performance of dynamic systems relying on global navigation satellite system (GNSS)-based services. Furthermore, the occurrence of scintillations in the equatorial and low latitudes can be triggered or inhibited during space weather events. In the present study, the possible presence of the EPBs during the geomagnetic storm periods under the 25th solar cycle is investigated using the GNSS-derived total electron content (TEC) depletion characteristics at a low-latitude equatorial ionization anomaly location, i.e., KL University, Guntur (Geographic 16°26′N, 80°37′E and dip 22°32′) in India. The detrended TEC with a specific window size is used to capture the characteristic depletion signatures, indicating the possible presence of the EPBs. Moreover, the TEC depletions, amplitude (S4) and phase scintillation (σφ) indices from multi-constellation GNSS signals are probed to verify the vulnerability of the signals towards the scintillation effects over the region. Observations confirm that all GNSS constellations witness TEC depletions between 15:00 UT and 18:00 UT, which is in good agreement with the recorded scintillation indices. We report characteristic depletion depths (22 to 45 TECU) and depletion times (28 to 48 min) across different constellations confirming the triggering of EPBs during the geomagnetic storm event on 23 April 2023. Unlikely, but the other storm events evidently inhibited TEC depletion, confirming suppressed EPBs. The results suggest that TEC depletions from the traditional geodetic GNSS stations could be used to substantiate the EPB characteristics for developing regional as well as global scintillation mitigation strategies.

Studying the Fixing Rate of GPS PPP Ambiguity Resolution Under Different Geomagnetic Storm Intensities

AbstractGlobal Positioning System (GPS) Precise Point Positioning (PPP) with correct fixing ambiguity resolution (AR) can reach cm‐mm level positioning accuracy. However, this accuracy can be degraded by the geomagnetic storm effects. To comprehensively investigate the ambiguity resolved percentage (ARP) of GPS kinematic PPP, referred to as PPP‐ARP, under different intensities of geomagnetic storms, based on the Natural Resources Canada's Canadian Spatial Reference System (CSRS) PPP, this study for the first time gives the correlation between the PPP‐ARP and storm intensity using 67 storms occurred in the past 5 years of 2018–2022. Experimental results indicate that the PPP‐ARP decreases gradually as the increase of geomagnetic storm intensity. Under quiet and low geomagnetic conditions (Dstmin > −50 nT), the PPP‐ARP of global GNSS stations can achieve more than 96%, while these during strong storms (Dstmin ≤ −100 nT) are generally lower than 90.0%, especially for the PPP‐ARP of some stations located at low latitudes which are lower than 40.0%. The mechanism of PPP‐ARP decrease under geomagnetic storms is mainly due to the cycle slips and even loss of lock of GNSS signals caused by the storms induced ionospheric disturbances and scintillations. In addition, different from many previous studies, we found that the CSRS‐PPP with AR can achieve good positioning accuracy (3D RMS <0.2 m) even under strong geomagnetic storms.