Dynamics of beryllium-7 specific activity in relation to meteorological variables, tropopause height, teleconnection indices and sunspot number

TL;DR

This study investigates the periodic behavior of beryllium-7 activity in surface air over 1987-2011 and its relation to meteorological variables, using wavelet and tdDMA analyses to reveal shared periodicities and autocorrelation patterns.

Contribution

It introduces a combined wavelet and tdDMA approach to analyze beryllium-7 activity and its connection to climate variables over multiple time scales.

Findings

Beryllium-7 activity exhibits periodicities at 1 month, 3 months, 1 year, and 3 years.

Strong autocorrelation of beryllium-7 activity at one-year and shorter intervals.

Shared periodicities and similar dynamics between beryllium-7 activity and teleconnection indices.

Abstract

The dynamics of the beryllium-7 specific activity in surface air over 1987--2011 is analyzed using wavelet transform (WT) analysis and time-dependent detrended moving average (tdDMA) method. WT analysis gives four periodicities in the beryllium-7 specific activity: one month, three months, one year, and three years. These intervals are further used in tdDMA to calculate local autocorrelation exponents for precipitation, tropopause height and teleconnection indices. Our results show that these parameters share common periods with the beryllium-7 surface concentration. tdDMA method indicates that on the characteristic intervals of one year and shorter, the beryllium-7 specific activity is strongly autocorrelated. On the three-year interval, the beryllium-7 specific activity shows periods of anticorrelation, implying slow changes in its dynamics that become evident only over a prolonged period of time. A comparison of the Hurst exponents of all the variables on the one- and three-year intervals suggest some similarities in their dynamics. Overall, a good agreement in the behavior of the teleconnection indices and specific activity of beryllium-7 in surface air is noted.