Open AccessDetermining long‐term change in the ionosphere
Author(s) -
Ulich Thomas,
Clilverd Mark A.,
Rishbeth Henry
Publication year - 2003
Publication title -
eos, transactions american geophysical union
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.316
H-Index - 86
eISSN - 2324-9250
pISSN - 0096-3941
DOI - 10.1029/2003eo520002
Subject(s) - ionosphere , ionosonde , thermosphere , term (time) , global warming , ionogram , meteorology , longitude , environmental science , climate change , climatology , geography , geology , geodesy , physics , geophysics , astronomy , oceanography , electron density , quantum mechanics , latitude , electron
Contemporary studies of long‐term changes in the ionosphere stem mostly from the suggestions by Roble and Dickinson [1989] that “global warming” in the lower atmosphere is accompanied by “global cooling” of the thermosphere, and subsequently, from the suggestion by Rishbeth [1990] that the resulting thermal contraction lowers the height of the ionospheric F2‐peak hm F2. The subject is attractive to study because decades of ionosonde data exist from dozens of stations worldwide, the data are well organized in a consistent format, and the analysis requires no great computing power. However, the trends from different stations are far from consistent and often show interruptions or reversals. There are tantalizing details, such as opposite trends of rising hm F2 at places east of longitude 30°E, falling hm F2 west of 30°E [ Bremer, 1998]. We have to ask: Are these real? Indeed, we should ask the more general question: “What is needed to make reported trends “believable”?