The phrase "a decrease in the magnitude of" is correct and usable in written English.
It can be used in contexts where you want to describe a reduction in size, intensity, or significance of something.
Example: "The study showed a decrease in the magnitude of the earthquake's impact over the years."
Alternatives: "a reduction in the extent of" or "a decline in the intensity of".
These earthquakes led to a decrease in the magnitude of stress in the Kamaishi regions after 1 year following the mainshock.
Local regions of enhanced flexibility or chain compaction are characterized by a decrease in the magnitude of the residual dipolar couplings.
This is attributed to a decrease in the magnitude of roughness-induced crack closure and the effective stress intensity range ΔKeff,th in the harmonic structured Ti 6Al 4V alloy due to the presence of fine grains.
During La Niña events 71% of models actually show a decrease in the magnitude of the NINO3.4 SST anomalies in E20C, while increases of 50, 58, and 67% are evident for the later periods (with E21C and L21C values again obtained under the RCP8.5 scenario).
In order to incorporate this climate mechanism, the TCM now includes the warming due to the vapor condensation by GCR, which causes a decrease in the magnitude of the WR.
Repetitive CSDs led to a decrease in the magnitude of long-term potentiation (LTP) in the hippocampus.
Additionally, a decrease of C eq results in a decrease in the magnitude.
Decreasing the packing pressure produced a significant decrease in the magnitude of residual stresses.
The decrease in width of the isotherms with increasing Zr concentration is due to a decrease in film thickness, leading to a decrease in the amount of hydrogen absorbed and hence the magnitude of the optical change.
Confirming this suggestion, we found that decreases in sequence frequency of the founder epitopes were associated with decreases in the magnitude of corresponding CTL responses.
