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tokens: human beings in near-Earth space, and provides a certain reference value in designing spacecraft materials in future deep-space exploration missions. Figure 8. GCR radiation dose rates on the lunar surface measured by the LRO/CRaTER. The horizontal dashed–dotted line marks the peak value of does rate in the solar minimum P 24/25 . 4. Conclusions The Sun was extraordinarily quiet during the recently complete solar cycle 24, with very low sunspot numbers, an extremely flat HCS, a reduced CME eruption rate, and a weak interplanetary magnetic field and turbulence level. The observed GCR intensities (both in interplanetary space and at the ground level) are sensitive to the heliospheric conditions, the so-called solar modulation. In this work, we focus on the variations of the GCR intensities for the period from 1997 through 2020 with measurements from the ACE/CRIS instrument, and investigate the influence of inner heliospheric environments on the GCR intensities. In addition, the long-term variations of the ground-based NM count rates are also studied. The conclusions are summarized as follows. 1. The GCR intensities observed at 1 au reach the highest levels in the solar minimum P 24/25 since the launch of the ACE spacecraft, which is ∼25% higher than that in the solar minimum P 22/23 and ∼6% higher than that in the solar minimum P 23/24 . With the extension of IMP-8 measurements and BON2020 numerical simulation results, we find that the GCR intensities during the recent solar minimum are at the highest levels since the start of the space age, having particle energies from tens to several hundred MeV nuc −1 . The record-breaking GCR intensities at 1 au increase the radiation dose rates near the lunar surface by ∼5% in comparison to those of the solar minimum P 23/24 , from the measurements of LRO/CRaTER instrument. 2. The peak value of NM count rates in the solar minimum P 24/25 is lower than that in late 2009. The difference between GCR intensities in interplanetary space and NM count rates seems to be relevant to the different modulation processes of the high- and low-energy particles. We think that the high-energy GCR particles are not as heavily modulated as the low-energy ones, which means the low-energy GCR particles are more likely to be influenced by varying solar modulation. An alternate or additional possibility is that the NM count rates are sensitive to the conditions of the Earth’s magnetosphere and atmosphere. It remains to be further studied in a future work. 3. We find that during the solar minimum P 24/25 , the mean solar polar field strength remains weak and is close to the value in the 2009 solar minimum; the HCS tilt angle reaches a minimum value of ∼2.1° in 2020 April, which is ∼22% lower than that in the solar minimum P 22/23 and ∼53% lower than that in the solar minimum P 23/24 ; the CME eruption rate is very small, and is less than half of the CME rate during the solar minima P 22/23 and P 23/24 ; the strength and