scholarly journals The solar-cycle variation of M(3000)F2 and its correlation with that of f0F2

1998 ◽  
Vol 41 (4) ◽  
Author(s):  
S. S. Kouris

Using hourly monthly-median measured values from nine long-standing ionospheric sounding stations with data sets extending over several decades, best-fit empirical relationships are established for M (3000)F2 with different solar and ionospheric indices representative of state of the solar cycle. The statistical analysis shows that there is no difference in the degree of correlation in using one index over another. Comparisons are also made with similar relationships for monthly median f0F2 determined from the corresponding measurement data sets and the degree of correlation between the two ionospheric parameters is established.

2014 ◽  
Vol 565 ◽  
pp. A44 ◽  
Author(s):  
S. J. Platten ◽  
C. E. Parnell ◽  
A. L. Haynes ◽  
E. R. Priest ◽  
D. H. Mackay

2011 ◽  
Vol 11 (10) ◽  
pp. 5045-5077 ◽  
Author(s):  
K. Semeniuk ◽  
V. I. Fomichev ◽  
J. C. McConnell ◽  
C. Fu ◽  
S. M. L. Melo ◽  
...  

Abstract. The impact of NOx and HOx production by three types of energetic particle precipitation (EPP), auroral zone medium and high energy electrons, solar proton events and galactic cosmic rays on the middle atmosphere is examined using a chemistry climate model. This process study uses ensemble simulations forced by transient EPP derived from observations with one-year repeating sea surface temperatures and fixed chemical boundary conditions for cases with and without solar cycle in irradiance. Our model results show a wintertime polar stratosphere ozone reduction of between 3 and 10 % in agreement with previous studies. EPP is found to modulate the radiative solar cycle effect in the middle atmosphere in a significant way, bringing temperature and ozone variations closer to observed patterns. The Southern Hemisphere polar vortex undergoes an intensification from solar minimum to solar maximum instead of a weakening. This changes the solar cycle variation of the Brewer-Dobson circulation, with a weakening during solar maxima compared to solar minima. In response, the tropical tropopause temperature manifests a statistically significant solar cycle variation resulting in about 4 % more water vapour transported into the lower tropical stratosphere during solar maxima compared to solar minima. This has implications for surface temperature variation due to the associated change in radiative forcing.


2016 ◽  
Vol 458 (4) ◽  
pp. 3691-3704 ◽  
Author(s):  
Justyna M. Sokół ◽  
Maciej Bzowski ◽  
Marzena A. Kubiak ◽  
Eberhard Möbius

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