A solut ion is given to the problem of r epresentin g the complex proper ties of ionospheri c cha racteristics on a worldwide scale, including their diurnal variation, by num eri cal analysis of ionospher ic data as t h ey a re obtained fr om a n etwork of so undin g statio ns, wit hout prior han d operations. The problem is co mpli cated by t wo bas ic diffi culties : (1) t he da ta ar e affected by noise (ran do m fiuctuation) an d (2) t he stations ar e irreg ularl y posit ion ed in t h e two s pace dim ens ions. The seco nd diffi culty is over co me by a gener al met hod for constructing fun ctions orthogonal relative to the dist ri bution of t he sta t ions . S pccial filterin g p ro cesses a re employed for t hc optimum separation of noise fr om real p hys ical var iat ions . The en d produ ct of t he a na lys is is a table of numerical coeffi cie nts de finin g a fun ction r (A, 0, I) of t hr ec variables, latit ud e (i--) , longitude (0) and ti me (I) , w hich can be used to compute t he io nospheri c characte ristic at a ny des ir ed location or instant of t ime. The method a pplies to a ny io nospheri c characte ristic; however, a s a means of illus tration we use in t h e p resent p a p er only t he characterist ic, monthly med ian of t he F2-laye r cri t ical fr eq uency (fo F,). _ 90' 80' 15 .BU~~~~AYA .2 9 ' 96 70' . 101 . 6' .49 .12 X 51. -55 f-.
No takes yet. Share an insight, caveat, or question.
Jones et al. (1962) studied this question.