资源环境科技发展态势分析平台

Changes in electron flux in Earth's outer radiation belt can be modeled using a diffusion‐based framework. Diffusion coefficients xmltex \beginMathtotextDxmltex \endMathtotext for such models are often constructed from statistical averages of observed inputs. Here we use stochastic parameterization to investigate the consequences of temporal variability in xmltex \beginMathtotextDxmltex \endMathtotext. Variability timescales are constrained using Van Allen Probe observations. Results from stochastic parameterization experiments are compared with experiments using xmltex \beginMathtotextDxmltex \endMathtotext constructed from averaged inputs, and an average of observation‐specific xmltex \beginMathtotextDxmltex \endMathtotext. We find that the evolution and final state of the numerical experiment depends upon the variability timescale of xmltex \beginMathtotextDxmltex \endMathtotext; experiments with longer variability timescales differ from those with shorter timescales, even when the time‐integrated diffusion is the same. Short variability timescale experiments converge with solutions obtained using an averaged observation‐specific xmltex \beginMathtotextDxmltex \endMathtotext, and both exhibit greater diffusion than experiments using the averaged‐input xmltex \beginMathtotextDxmltex \endMathtotext. These experiments reveal the importance of temporal variability in radiation belt diffusion.