plasma effects on transionospheric propagation of radio waves...

21
International Summer School for Ionospheric Physics, Erice, 24-29 September 2004 R. Leitinger, Univ. Graz, I. of Physics, I. for Geophysics, Astrophysics and Meteorology Transionospheric propagation of radio waves Plasma effects on transionospheric propagation of radio waves II Plasma effects on Plasma effects on transionospheric transionospheric propagation of radio waves II propagation of radio waves II R. Leitinger

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Page 1: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Plas

ma

effe

cts

on tr

ansi

onos

pher

icpr

opag

atio

n of

radi

o w

aves

IIPl

asm

a ef

fect

s on

Pl

asm

a ef

fect

s on

tran

sion

osph

eric

tran

sion

osph

eric

prop

agat

ion

of ra

dio

wav

es II

prop

agat

ion

of ra

dio

wav

es II

R. L

eitin

ger

Page 2: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

•G

ener

al re

mar

ks•

Rem

inde

r on

(tran

sion

osph

eric

) wav

e pr

opag

atio

n•

Rem

inde

r of p

ropa

gatio

n ef

fect

s•

GPS

as

a da

ta s

ourc

e•

Som

e el

ectr

on c

onte

nt e

xam

ples

Seco

nd le

ctur

e: M

oder

n ap

plic

atio

ns

•TE

CTE

C m

appi

ng, a

dapt

ive

mod

ellin

g, (d

ata

inge

stio

n in

to m

odel

s, d

ata

assi

mila

tion)

•In

vers

ion

Tom

ogra

phy

3D a

nd 4

D im

agin

g (fi

lling

vox

els

with

dat

a)

Iono

sphe

ric R

adio

Occ

ulta

tion

•Th

e im

port

ance

of a

sses

smen

t stu

dies

Page 3: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

GPS

as

a da

ta s

ourc

eTh

e “c

lass

ical

” TEC

sou

rces

pro

vide

dor

fixe

d ge

omet

ry a

nd h

igh

tem

pora

l res

olut

ion

(GEO

Far

aday

bea

cons

)or

nea

rly c

onst

ant L

ocal

Tim

e an

d hi

gh s

patia

l (la

titud

inal

) res

olut

ion

(LEO

Diff

.D

oppl

er b

eaco

ns)

true

sign

al a

mpl

itude

and

pha

seG

PS (M

EO o

rbit;

12

hour

per

iod,

incl

inat

ion

53 d

egre

es)

mix

es te

mpo

ral a

nd s

patia

l dep

ende

nce

(diu

rnal

cur

ves

of T

EC fo

r a g

iven

loca

tion

are

alw

ays

com

posi

tes,

etc

.)N

eeds

com

plic

ated

“cal

ibra

tion”

pro

cedu

res

(CO

DE

= G

roup

Del

ay n

eeds

kno

wle

dge

of tr

ansm

itter

and

rece

iver

del

ays

and

cann

otpr

ovid

e su

ffici

ent r

esol

utio

n fo

r sci

ence

app

licat

ions

, PH

ASE

= D

iff. D

oppl

er s

uffe

rsfro

m 2

am

bigu

ity

CO

DE

and

PHAS

E co

mbi

natio

n ne

eded

for a

ll sc

ienc

eap

plic

atio

ns)

Am

plitu

de a

nd p

hase

are

“re

cons

truc

ted”

in th

e re

ceiv

erG

PS-s

TEC

is th

e su

m o

f ion

osph

eric

plu

s pl

asm

asph

eric

con

tent

Ther

efor

e: T

EC m

appi

ng, a

dapt

ive

mod

ellin

g, d

ata

inge

stio

n in

to m

odel

s, …

Page 4: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Exam

ple

for F

arad

ay o

bser

vatio

ns o

n th

e si

gnal

s of

the

geos

tatio

nary

sat

ellit

e M

ETEO

SAT-

2 m

ade

at F

irenz

e on

25 a

nd 2

6 M

ay, 1

991.

TEC

in u

nits

of 1

015 m

− 2 v

s.U

nive

rsal

Tim

e in

hou

rs. D

iurn

al c

urve

; str

ong

day

toda

y va

riatio

ns; v

ery

stro

ng T

ID a

ctiv

ity o

n 25

May

.

Page 5: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Exam

ple

for a

str

ong

posi

tive

stor

m e

ffect

in io

nosp

heric

ele

ctro

n co

nten

t: Su

dden

Com

men

cem

ent o

f the

geo

mag

netic

stor

m (S

SC) o

n 4

Febr

urar

y, 1

983,

16:

15 U

T, D

st-m

inim

a: -1

59 n

T on

4 F

eb.,

20 U

T, -1

69 n

T on

5 F

eb.,

11 U

T. F

arad

ay e

ffect

on g

eost

atio

nary

sat

ellit

e si

gnal

rece

ived

at H

amilt

on, M

A, U

SA (4

00 k

m io

nosp

h. p

oint

: 39°

N, 2

89°E

; geo

mag

n. la

t. 50

°).

Ord

inat

e: e

lect

ron

cont

ent i

n un

its o

f 1015

m− 2

, abs

ciss

a: U

nive

rsal

Tim

e (U

T). 3

Feb

ruar

y; q

uiet

refe

renc

e da

y (A

p=7)

.In

term

edia

te le

vel o

f sol

ar a

ctiv

ity (m

onth

ly m

ean

suns

pot n

umbe

r R=5

1).

Page 6: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Exam

ple

for a

str

ong

nega

tive

stor

m e

ffect

in io

nosp

heric

ele

ctro

n co

nten

t: Su

dden

Com

men

cem

ent o

f the

geo

mag

netic

stor

m (S

SC) o

n 11

Apr

il, 1

981,

13:

39 U

T, D

st-m

inim

a: -1

67 n

T on

12

April

, 6 U

T, -2

91 n

T on

13

April

, 7 U

T. F

arad

ay e

ffect

on

geos

tatio

nary

sat

ellit

e si

gnal

rece

ived

at M

adrid

, Spa

in (4

00 k

m io

nosp

h. p

oint

: 37°

N, -

4°E;

geo

mag

n. la

t. 41

°). O

rdin

ate:

elec

tron

cont

ent i

n un

its o

f 1015

m− 2

, abs

ciss

a: U

nive

rsal

Tim

e (U

T). 1

1 Ap

ril w

as a

slig

htly

dis

turb

ed d

ay (A

p=39

). Th

e ne

gativ

est

orm

effe

ct w

as p

rono

unce

d in

the

long

itude

zon

e ar

ound

0° o

nly.

Hig

h so

lar a

ctiv

ity (m

onth

ly m

ean

R=1

56).

Page 7: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Exam

ple

for l

atitu

dina

l pro

files

of v

ertic

al e

lect

ron

cont

ent f

rom

NN

SS o

bser

vatio

ns m

ade

at G

raz

dem

onst

ratin

g th

e po

tent

ial

of c

ombi

ned

obse

rvat

ions

for t

imes

of h

igh

sola

r act

ivity

. Dat

aof

1 N

ovem

ber,

1990

. Ele

ctro

n co

nten

t in

units

of 1

015 m

− 2 v

s.ge

ogr,

latit

ude

in d

eg. N

(N to

S).

Upp

er p

anel

: tra

ces

of th

eio

nosp

heric

poi

nts

(in 4

00 k

m h

eigh

t) in

a g

eogr

aphi

c sy

stem

.Ev

en fo

r mid

latit

udes

the

equa

toria

l ano

mal

y is

impo

rtan

t!

Page 8: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Exam

ple

for l

atitu

dina

l pro

files

of v

ertic

al e

lect

ron

cont

ent f

rom

NN

SS o

bser

vatio

ns m

ade

at G

raz

dem

onst

ratin

g th

e po

tent

ial

of c

ombi

ned

obse

rvat

ions

for t

imes

of h

igh

sola

r act

ivity

.Af

tern

oon/

even

ing

of 2

Nov

embe

r, 19

90. E

lect

ron

cont

ent i

nun

its o

f 1015

m− 2

vs.

geo

gr, l

atitu

de in

deg

. N (N

to S

). U

pper

pane

l: tra

ces

of th

e io

nosp

heric

poi

nts

(in 4

00 k

m h

eigh

t) in

age

ogra

phic

sys

tem

. In

the

early

eve

ning

the

effe

ct o

f the

equa

toria

l ano

mal

y is

eve

n m

ore

pron

ounc

ed!

Page 9: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Latit

ude

depe

nden

ce o

f TEC

from

Diff

. Dop

pler

on

the

150/

400

MH

z si

gnal

s of

NN

SS. R

ecei

ving

sta

tions

Gra

z(4

7.1°

N, 1

5.5°

E) a

nd U

ppsa

la (5

9.8°

N, 1

7.6°

E). T

ypic

aleq

ujin

ox/w

inte

r nig

ht p

rofil

e. M

ain

troug

h w

ith m

inim

umar

ound

60°

N. I

ndic

atio

n of

TEC

incr

ease

tow

ards

the

equa

toria

l ano

mal

y in

the

Sout

h. 1

8 O

ctob

er, 1

989

arou

nd 2

1:10

UT.

TEC

in u

nits

of 1

015 m

− 2 v

s ge

ogra

phic

latit

ude.

Upp

er p

anel

: tra

ces

of th

e io

nosp

heric

poi

nts

(in40

0 km

hei

ght)

in a

geo

grap

hic

syst

em. H

igh

sola

r act

ivity

(mon

thly

mea

n R

=159

, mon

thly

mea

n 10

.7 c

m s

olar

radi

oflu

x: 2

09 u

nits

).

Page 10: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Latit

ude

depe

nden

ce o

f TEC

from

Diff

. Dop

pler

on

the

150

/ 400

MH

z si

gnal

s of

NN

SS. R

ecei

ving

sta

tion

Dio

nyso

s (3

8.1°

N,

23.0

°E) a

nd U

ppsa

la (5

9.8°

N, 1

7.6°

E). T

EC in

uni

ts o

f 1016

m− 2

vs

geog

raph

ic la

titud

e. 8

Apr

il, 1

981,

aro

und

11:4

0 U

T.M

onth

ly m

ean

R=1

56, m

onth

ly m

ean

10.7

cm

sol

ar ra

dio

flux:

223

uni

ts).

Geo

mag

netic

ally

nea

rly q

uiet

(Ap=

11).

Very

hig

h va

lues

of

TEC

Page 11: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Elec

tron

con

tent

(TEC

) map

s g

loba

l (bi

-hou

rly)

regi

onal

(30

min

utes

)(s

omeh

ow) b

ased

on

mod

els

glob

al m

aps

need

dat

a in

terp

olat

ion

(dire

ctly

or i

ndire

ctly

by

mod

el)

Inte

rnat

iona

l GPS

Ser

vice

(IG

S): 6

glo

bal m

aps

(by

thei

r reg

iona

lce

nter

s) +

one

offi

cial

pro

duct

(= a

vera

ge !!

)

La P

lata

map

s

DLR

Neu

stre

litz

regi

onal

map

s (b

ased

on

adap

tive

mod

el)

Page 12: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

tom

ogra

phy

occu

ltatio

n in

vers

ion

com

bine

d sp

ace-

grou

ndto

mog

raph

y

Iono

sphe

ric R

adio

Occ

ulta

tion

Page 13: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

„Occ

ulta

tion“

rays

from

the

GN

S to

the

LEO

. Sla

nt e

lect

ron

cont

ent (

sTEC

)co

nsis

ts o

f thr

ee p

arts

: ion

osph

ere

(P to

P’),

upp

erm

ost i

onos

pher

e (P

’ to

U in

2000

km

hei

ght),

pla

smas

pher

e (U

to G

). Ea

ch ra

y ca

n be

cha

ract

eris

ed b

y its

perig

ee (t

ange

nt p

oint

). In

real

ity th

e ra

ys a

re n

ot c

o-pl

anar

and

the

loca

tion

ofth

eir p

erig

ees

form

s a

3D c

urve

. Its

pro

ject

ion

to th

e su

rface

of t

he E

arth

is th

e„s

ink

path

“. U

seab

le („

good

“) o

ccul

tatio

ns h

ave

a io

nosp

heric

sin

k pa

th le

ngth

of

< 10

° (gr

ound

occ

ulta

tion

poin

t to

perig

ee o

f the

hig

hest

pos

sibl

e ra

y).

Page 14: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Iono

sphe

ric u

se o

f Rad

io O

ccul

tatio

n•

Prim

ary

info

rmat

ion

are

(unc

alib

rate

d) G

NS

to L

EO e

lect

ron

cont

ent v

alue

s I s

usua

lly g

aine

d by

mea

ns o

f car

rier p

hase

diff

eren

ces.

Subt

ract

ion

of th

e el

ectro

n co

nten

ts o

f “u

pper

mos

t ion

osph

ere”

and

“pla

smas

pher

e” le

ads

to th

e “i

onos

pher

ic”

elec

tron

con

tent

whi

ch is

sub

ject

edto

inve

rsio

n

I I = I s

- I U

- I P

•R

efra

ctio

n (ra

y be

ndin

g) is

neg

ligib

le

⇒ s

traig

ht li

ne p

ropa

gatio

n is

ass

umed

⇒ c

ontin

uous

sol

utio

ns a

re u

niqu

e ev

en if

refra

ctiv

ity is

not

incr

easi

ng /

decr

easi

ng m

onot

onou

sly

(ver

y im

porta

nt b

ecau

se o

f ele

ctro

n de

nsity

pro

files

with

F2 m

axim

um (a

nd E

max

imum

).

⇒ d

iscr

ete

prob

lem

has

stra

ight

forw

ard

trian

gula

r des

ign

mat

rix (c

onsi

sts

of p

ath

leng

th e

lem

ents

)

⇒ (“

onio

n pe

elin

g”) s

olut

ions

are

inhe

rent

ly s

tabl

e w

ith e

rror a

ccum

ulat

ion

in th

ebo

ttom

of t

he e

lect

ron

dens

ity p

rofil

e

Page 15: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Iono

sphe

ric u

se o

f Rad

io O

ccul

tatio

n•

We

shou

ld d

istin

guis

h be

twee

na)

“hig

h” L

EO o

rbit

( hLE

O>7

00 k

m) (

HL)

and

b) “l

ow” L

EO o

rbit

( hLE

O<7

00 k

m) (

LL) c

ases

LL e

xper

ienc

e fro

m C

HAM

P ( C

HA

lleng

ing

Min

isat

ellit

e Pa

yloa

d):

h

LEO

> h m

F2 i

s a

nece

ssar

y co

nditi

on fo

r “io

nosp

heric

” inv

ersi

on!

•H

L: M

odel

ass

ista

nce

of a

dvan

tage

in re

mov

ing

I U a

nd I P

LL: M

odel

ass

ista

nce

and/

or “h

igh

elev

atio

n” e

lect

ron

cont

ent d

ata

(LEO

toad

ditio

nal G

NS)

nec

essa

ry in

rem

ovin

g I U

and

I P•

Mod

el a

ssis

tanc

e ca

n st

rong

ly im

prov

e th

e re

liabi

lity

of in

vers

ion

resu

lts in

the

vici

nity

of i

onis

atio

n rid

ges

(max

ima

in th

e TE

C d

istr

ibut

ion)

and

trou

ghs

(min

ima

in th

e TE

C d

istr

ibut

ion)

An

othe

r typ

e of

mod

el a

ssis

tanc

e w

as v

ery

succ

essf

ul in

CH

AM

Pin

vers

ion

(N. J

akow

ski e

t al.

at D

LR N

eust

relit

z) (a

dapt

ive

mod

els

for t

he io

nosp

here

[and

pla

smas

pher

e] a

bove

the

CH

AM

P or

bit)

Page 16: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Exte

nsiv

e ca

lcul

atio

ns w

ere

carri

ed o

ut o

n th

e ba

sis

of th

e th

ree

dim

ensi

onal

and

time

depe

nden

t ion

osph

ere/

plas

mas

pher

e m

odel

NeU

oG-p

las

(Hoc

hegg

eran

d Le

iting

er, 2

000)

. Th

e fo

llow

ing

four

par

amet

ers

of e

lect

ron

dens

ity h

eigh

tpr

ofile

s w

ere

inve

stig

ated

:

- pea

k he

ight

hm

F2,

(bes

t – e

rror <

20 k

m in

mor

e th

an 5

0% o

f the

cas

es)

- pea

k el

ectro

n de

nsity

Nm

F2, (

seco

nd –

for f

ar m

ore

than

50%

of t

he c

ases

erro

r <15

%.

- top

side

sca

le h

eigh

t or t

opsi

de s

lab

thic

knes

s,

- a s

hape

par

amet

er fo

r the

bot

tom

side

iono

sphe

re (n

ot re

ally

goo

d).

The

low

latit

udes

exc

eptio

n re

gion

: vic

inity

of o

ne o

f the

cre

sts

of th

eeq

uato

rial a

nom

aly

and

(to a

less

er d

egre

e) th

e re

gion

aro

und

the

dip

equa

tor

– m

odel

ass

ista

nce

can

impr

ove

situ

atio

n su

bsta

ntia

lly

Page 17: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Nec

essi

ty o

f Ass

essm

ent s

tudi

es o

n th

e ba

sis

of re

alis

tic m

odel

s•

Cal

cula

te a

rtific

ial t

rans

mitt

er to

rece

iver

ele

ctro

n co

nten

ts (s

TEC

)

•Su

bjec

t sTE

C s

erie

s to

retri

eval

/ in

vers

ion

met

hod

•C

ompa

re re

triev

al /

inve

rsio

n re

sults

with

“m

odel

trut

h”

Page 18: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Elec

tron

dens

ity fr

om N

eUoG

-pla

s3

GN

S to

LEO

rays

: gro

und

occu

ltatio

n(ta

ngen

t hei

ght h

t = 0

km

), ne

ar F

laye

r pea

k(h

t = 3

00 k

m),

“hig

h” ra

y (h

t = 3

00 k

m).

Page 19: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

heig

ht p

rofil

es o

f ele

ctro

n de

nsity

;bl

ack:

giv

en p

rofil

e, b

lue:

dire

ctin

vers

ion,

red:

mod

el a

ssis

ted

inve

rsio

n.

Hor

izon

tal d

istri

butio

n of

Nm

ax(c

onto

urs

over

geo

grap

hic

syst

ems)

in th

e oc

culta

tion

regi

on; b

lue

low

valu

es, r

ed h

igh

valu

es; o

ccul

tatio

nra

ys (t

hin

red)

and

occ

ulta

tion

path

(thic

k re

d).

Nm

ax d

istri

butio

n al

ong

the

grou

ndoc

culta

tion

ray

botto

m: s

ymm

etric

(red

) and

ant

imet

ric (l

ight

blu

e) p

art.

Dat

a ba

se: a

rtific

ial s

TEC

val

ues,

cal

cula

ted

by m

eans

of N

eUoG

-pla

s w

ith o

ne G

PS to

LEO

scen

ario

shi

fted

in g

eogr

aphi

c la

titud

e, s

easo

n an

d lo

cal t

ime

to e

ncou

nter

cre

st a

nd v

alle

yco

nditi

ons.

Page 20: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

heig

ht p

rofil

es o

f ele

ctro

n de

nsity

;bl

ack:

giv

en p

rofil

e, b

lue:

dire

ctin

vers

ion,

red:

mod

el a

ssis

ted

inve

rsio

n.

Hor

izon

tal d

istri

butio

n of

Nm

ax(c

onto

urs

over

geo

grap

hic

syst

ems)

in th

e oc

culta

tion

regi

on; b

lue

low

valu

es, r

ed h

igh

valu

es; o

ccul

tatio

nra

ys (t

hin

red)

and

occ

ulta

tion

path

(thic

k re

d).

Nm

ax d

istri

butio

n al

ong

the

grou

ndoc

culta

tion

ray

botto

m: s

ymm

etric

par

t (re

d) a

nd m

odel

for i

t (bl

ue).

Dat

a ba

se: a

rtific

ial s

TEC

val

ues,

cal

cula

ted

by m

eans

of N

eUoG

-pla

s w

ith o

ne G

PS to

LEO

scen

ario

shi

fted

in g

eogr

aphi

c la

titud

e, s

easo

n an

d lo

cal t

ime

to e

ncou

nter

cre

st a

nd v

alle

yco

nditi

ons.

Page 21: Plasma effects on transionospheric propagation of radio waves IIlegacy.ingv.it/roma/convegni-seminari/ericesept2004/... · 2009-01-21 · R. Leitinger, Univ. Graz, I. of Physics,

Inte

rnat

iona

l Sum

mer

Sch

ool f

or Io

nosp

heric

Phy

sics

, Eric

e, 2

4-29

Sep

tem

ber 2

004

R. L

eitin

ger,

Uni

v. G

raz,

I. o

f Phy

sics

, I. f

or G

eoph

ysic

s, A

stro

phys

ics

and

Met

eoro

logy

Tran

siono

sphe

ric p

ropa

gatio

n of

radi

o wa

ves

Than

k yo

u fo

r you

r atte

ntio

nTh

ank

you

for y

our a

ttent

ion