port PTTTEpT Try prrtrypt rrr rt i Pty rrr

1!

0800
0800

0400

0000
+ 6 January, 1968——_|

0400

TT TT

T

2000
2000

|
°
i
H
1
|
i
i
H
1
|
f
i
+
i
|
|
|
i
i
H
i
\
|
H
'
f
|
H
H
;
+
f
is

i:

i
I
nm
H
i
i

©
2
2
S
5
=
“
=
3
2
3
3
&
=
gS
s
fd
uw
3
2

No F-Regio
3

T

1600

0000
}/}——-28 December, 1967 (75° W Time) +2 December, 1967-——|
T T T T T T
rift Dota Until 4 March, 1968

T
4—t :
i L i _
0800 1600
}———5 January 1968 (75° W Time)

(200
—

|
1200

L 4 L.
drititiiiis Lissitisii) Lil Bi itiidits itititit} | Nl
& _ 38 © 38 2 8 2 8 ° 88 _ 8
(9es/w) (9887) Ss J Pd a (9@s/w) (998/W) 7
4414Q [D91448A, 4440 M-3 ca) yibuays platy HUQ [DoIEA, WG M-3 (4) yjbuays pjaiy
uoibay -4 uo!Bay-9 oyeuBbby uolbay- 4 uo|bay-3 * oyeubpy,


TTTT TTT ry] | TTT ]TTTt l { TTTT] TiTtt T TT i o TTTT TTT TM" [ TTTT TTTT ] [ TTTT | TTTT | TT T
- rel g
8
g 8
< =
2e ef
=3 ss
XN o
nN
2 g
8s 3s
L 2 4 rF 2
| 8 +4 | 8 ®
= 2 = =
L 3 ; 4 L & f
< mo lorw 5
- 3 | j22 | 3 aa
& E @
i _- Fog | ES
re ae t a 4 = 2 a CN NY AO =
4] & | a
[ loa [ £
L jg 2 L 8
3 8 | 3 8
z lg [ €
f i 72 5 e
7 | 4 3 r =
[. jgo L. su
| 4 L
[ | Wyo
L » L
roottisti) Lireetivii} Lin not} rottisii} Lerirtiiii| s
ss G8 °S 328 8 § g© # = Bg > 6 =
(2as/w) (oasyw) os s S S (9as7w) (9987) ‘
ON uu M-3 (4) Wibuadis pial 434Q 194A Wd M-3 4) yibuanis play

uoibay-4 uoibay-3 oyaubow, uoibay- 4 uolbay-3 oyeubow,


Trrt

0800

0400

2000 0000
1968. (75° W Time) —————+-—13. December , 1968 ———|

1600

1200

b= !2 December

yt

Litt
8

(9as/w)
4414q [091449A,
uojbay - 4

so

riiit
=
8

(2as/w)
Ud M-3
uoibay-3

8
(4) y6uarys

0800

~500

HQ |DOHZBA,

0800

0400

}/-————- 8 January, 1969 (75° W Time) ————-+-9 January, 1969

1600 2000 0000

1200

3
Ss 8 38 =
= = s oS
4%) WibuARS Plats

oueaubby

35


TT

Ss
B

TREE TTT Paya pet TO pe pepo
[ q del £ tg
Lf H
a a
= . a
gL dg
° SN 0
48 L s
r I s a1
Ls + Ls 4
8 4 a | 3 _
5 a s & yle
| @ | 8 JF [ @ » ay
Sie SS SRE Sie IEEE cecaaiens tae Po 8 44
a nD Cs Oa “eT s }----2 —-
L | ? | ®
eg |.
s
- + ) fae + g
L + 2 |. -
7 =
L 41 ¢é L
2
L 4 4 § L
L dgo g
oF = sg
+ —4 L I
L ae a L
petitive s) Lisietriies Lie tides uiilg piitiiiis Lisis tiiii | s
= 88 ° 88 2 s 3 8 = 8B = 8 °
(908/w) (998/w) "3 g S S (99s) (oasyw)
HQ [OO EA, 40 M-3 4) yybueas platy ASG [B91] 418A, 444 M-3 x
uojbey-4 uolbey-3 oeuboy, uolbay- 4 uoibey-3 oyauboyy

_

i]
+|

{3 March ,1970

s1970 (75° W Time)

}——2 March

44


0800

0400

——_—-+—— 22 September, 1967 ——|

i
1200
[+2 September, 1967 (75° W Time)

a roy perp a TTT] peeery rrr yr ray
EL ne] [- § mo
ee q ee Cee tS
Foon aR =, : a 8
L : = q
t =, me
L R °
a @
L 8 ; 4
2 s
t ¢ 2 Lz
[ =
Lo = 4
=
| 5
2
L 8 a
| = £
ga -
| fF fo
| 3 ~
L 8
L a
3
3
1 2 L 44
L 2 |
¢
L as + 4
roittiisi} Lirertiiiid | wills retitisit) Lisette} Led ls
8 ° 8B > 38 ° 8 ° 8 8 . 883 8 82 8
(29s/w) (sasyw) ] S (098/wW) (oasyuw) = S x
HUQ {O9N49A, 44d M-3 xf 4) yjbuays pjaty HUG |DOHJEA, HUQ M-3 4) yybuaas plats
uolbay- 4 uolbey-3 oaubpy) uo}6ay- 4 uo1bay-3 oyeubpy

0800

12


TTT]

prt

TITTY]

2
L 3
LS
_--§ --.
_—
fia
—
+ 2
+
potitiviit Liriitiiiy
es = 8g > 8
(98S/W) (9as/w) ‘
4H 1DOI48A, HHO M-4
uolbay-4 uojbey-3

pa

28,100

TTT yt

i
0000 0400 0800
5 March,!968

2000

1600

1200

}-———14 March, 1968 (75° W Time)

0800

2 ¢
a 8

(4) yibuexs plaid

27,800

* oaubpy)

16 March, 1968-4

1600
» 1968 (75° W Time)

1200

-+———— {5 March,

PTTTT TTT] PTTTTyT Trt] prt
r 2
| 3
| &
5
L &
«
fo
Liitiiiil Litttiiiii)
i BB ° g
(08s/w) (98s/w) x
ASC 1D9}148A, 434 M-3 (4) yibuads pjaty
uolbay-4 uoifay-3 * ouauBoyy

0800

22


i PUTT tyr
© |

TTTT TT TTT] frerrytr try pert

0800
0800

0400

2000 0000
29 May,I969_ (75° W Time) + 30 May, {9692 |
40

0400

ee ce i

T
n
+

1600

2000 0000
--———28 May, 1969 (75° W Time) +29 May 1969 ———|
T T T T T T
i + 2 +

1600

1200
1200

ro

T T T
3—+—-3—_+-—3

pitttisii) Lipiitiiny 3 peiPliret) Line vet} Lb tiwile
8 _ 8 8 ° s 8 = 88 _ 88 3 = 8°
(9@s/w) (98s/w) (9887) (988/W) "3 S 7
4444Q |D9} eA, HUQ M-3 ¥ HUG [Dd14eA, UG M-3 ie) yjbuasg pjal4

uoibay~ 4 uo!bay-3 oyaubpy uo)Bay-4 uolbay-3 oyeuboyy


The vertical axis for the F-region data is scaled between 450 m/sec; the positive values corre-
spond to upward drifts while the negative values represent downward drifts. The horizontal~dashed
lines that appear occasionally at the -50 m/sec leyel of the F-region curves indicate times of system
outage. The shaded horizontal strips that appear on the zero m/sec line indicate periods of occur-
rence of equatorial spread F at some height over the observatory. When these irregularities occurred
outside of the 300-400 km region (where the average F-region drifts are obtained), both types of data
(F-region drift velocities and spread-F occurrence) are shown. When the irregularities occurred with-
in this height range, the normal drift measurements were not possible. In these instances, if it was
possible to obtain a representative drift velocity value from a higher region, these results are plot-
ted as dashed lines. If the irregularities were very strong and/or occurred throughout the entire F
region, then no data are plotted.

The E-region curves are scaled between + 500 m/sec; positive for westward drift yelocities. As
in the F-region curves, the horizontal-dashed lines at the -500 m/sec level indicate periods of system
outage. The horizontal-dashed lines that appear occasionally at the 4360 m/sec levels show the nomin-
al critical drift velocity (V,_,) for the generation of the two-stream irregularities. Finally, the
small circles'that replace the E-region curves when the drift velocity approaches +500 m/sec indicate
that determination of the drift velocity is precluded by the presence of strong two-stream echoes.

The vertical-dashed lines indicated by SR, SS, SR', SS' indicate the approximate times of local
ground sunrise (SR) and sunset (SS), and sunrise (SR') and sunset (SS') at a height of 100 km (the
approximate height of the equatorial electrojet). These data were obtained from Colin and Myers
[1966].

The horizontal component of the Huancayo magnetogram has been plotted assuming a baseline of
27,750 y for all records. This baseline value was taken from the 1967 Huancayo magnetic records.
The actual baseline values during the 1967-1970 observation period increased gradually by about
13 y (the pronounced decrease in the nighttime level apparent during the period ts much larger than
this and is due to secular variations in the earth's magnetic field [Campbell, 1971]). Reference
should be made to the original records if accuracies comparable to variations of this magnitude are
desired, particularly since the magnetic field strength curves shown here are merely handsmoothed
rescalings of the actual data, and are meant mainly for visual comparison with the other data.

For further convenience, the three-hour averaged values of the Huancayo K indices are shown at
the bottom of each figure. These values were obtained from the actual scalings made at the Huancayo
Observatory, which were included in the standard magnetic records.

Acknowledgements

We are pleased to acknowledge the help of the staff of the Jicamarca Radar Observatory in
obtaining the ionospheric drift data included in this report. The Huancayo magnetic data were
provided by Mr, William Paulishak of the World Data Center A, Geomagnetism, of the National Oceanic
and Atmospheric Administration, Boulder, Colorado. We are also indebted to the staff of the World
Data Center A, Upper Atmosphere Geophysics, NOAA, Boulder, Colorado, for their cooperation in the
preparation of this report.

REFERENCES

BALSLEY, B. B. 19698 Some Characteristics of Non-two-Stream Irregularities in
the Equatorial Electrojet, J. Geophys. Res., 74, 2333-2347.

YBALSLEY, B. B. 1969 Measurement of Electron Drift Velocities in the Nighttime
Equatorial Electrojet, J. Atmosph. Terrest. Phys., 31,
415-478.

BALSLEY, B. B. 1970a A Longitudinal Variation of Electron Drift Veloctty in the
Equatorial Electrojet, J. Geophys. Res., 75, 4291-
4297.

BALSLEY, B. B. 1970b The Equatorial Electrojet: Seasonal Variation of the
Reversal Times, J. Geophys. Res., 75, 4369-4371.

CAMPBELL, W. He Private communication,

COLIN, LAWRENCE and 1966 Computed Times of Sunrise and Sunset in the Tonosphere,

MARILY A, MYERS NASA Technical Memorandum X-1233.

FARLEY, D. T. 1963 A Plasma Instability Resulting in Field-aligned Trregular-

ities in the Ionosphere, J. Geophys. Res., 68, 6083.



TTTTy]Trrt TTXTTTTTt TTTTYT TIX] TTT TTT TT TT TTTTYT TITTY. VTTT] tT
| y 1] lf T T Ml e] [ \ lf 1 of ] gs
8 8
L +
—— ee 51 eeeeeeeeeeeeeaeion S| @
a ee rn a tls8 3
| Se s
L Is
«| 8
| | 2
I “ £ i s
L 4
|_ “a ae et Ss
a a Re =
ac Live
b-- [ocoouremkes specs
b+ ~ ----|----------=----4}-- 2 as
a| &
[ 1e8
t 42 3
L IW gs
|. 4 €£
t {8s g
4 S
if
L 1 _|
[ va [
bititiiit Hoi) Loitii tis bititisit} Lirritiiiitd Liriil
a ~, #8 8 & 8° ee BU UB S
(98s/W) (98s/) "8 ] a 7 (98s/w) (9as/w) s gS Es} fi
4y}4d [DOH 4EA, 4340 M-2 x*) yrbuedts plaid 444d [ooysEA, WUC M-3 x4) MbuEUS pial
uoibay- 4 uoibey-3 oyeubpyy uo}Bay - 4 uolbay-3 oyeubow

———}— 27 November, 1968-—-—|

33

[+ 26 November, 1968 (75° W Time)


Orift Data Until 4 Morch, 1968

TT T1734
No F-Region

0800

0400

"2000

0000
[+18 January, 1968 (75° W Time) —————+—— 19 January, 1968 -——|
T T T T T
Drift Data Until 4 March, 1868.

No F-Region

1600

1200

ee ee TrTTy Tar

—_ “ff

v

0800

bos
© 74

n
+
i
0400

2 + 2 +
1 L 1 1 i 1
0000
+20 January 1968 ——4

S
LL.
2000

19

4
t
i
1600

L
1200

F-3—+—5
j 1
0800
|—19 January,1968 (75° W Time)

roittisiis Lisi tiie 3 Lotitiiis roritiiiid Lh visit
S Ss BS = Es 3 = = 2s 3 a 8
(9as/w) (098/W) (98s/w) (9as/W) " 3 = 5 S
HUQ 1D9ILEA, HUG M-3 x HQ |DOWIEA, 444d M-3 (4) ybuads play
uobay - 4 uolbay-3 oleubpy uoibay- 4 uoibey- 3 oeuboy


TIT] prey yr

Ss
B

=

(988 /w)
40 M-3
uoibay -3

HUQ 1D 489A,

S
s
?

28,100

s 8
s =e

(4) yibuas platy

* olyaubp)

0800

0400
lO May ,1968

0400
9 May, 1968

0000

2000

—Vieg
2000

25

na

1600

}-_—8 May, 1968 (75° W Time)

1600

1200
1200

[+ 9 May, 1968 (75° W Time)

0800
50
0800

28,10

Ss S
HIG [D911 48A, (4) ysbuaas plats


TTTTTTTITT] f

TTTT

0800

0400
5 March. 1968

1600 2000 0000

(200

TTTTYTTTT] Perry er yyy part

rrryprr yr

a

b+ 4 March, 1968 (75° W Time)

w-| | +4
potrtivitt Liriitiiis| Liriil Luiils miTititii) Lisi tiriis Liviel mn
Faw ae PE 2 8 & F § Be = Be EB g &
(ess) (9as/w) a) s S es] (98S/ul) (9as7w) 7 s S 7
4JU4Q JOOHeA, HQ M-3 xo) unbuads platy 4344Q [DOH eA, UC M-3 x4) Wibuadis plat
uoibay-4 uoiBay -3 oyeubo,) uolbey -4 uolhay-3 oljeubpy)

1200 1600 2000 0000 0400 0800
——_—+—6 March, 1968 ——

|} 5 March, 1968 (75° W Time

0800

)

2l


T

TTT] TTT]

PUTT yr] opty ttt

0800

0400

}+-27 November ,1968 (75° W Time)-—-+—-28 November , 18968 ——|

2000 0000

1600

TTT TTT Tt ry

2
L 413 |.
Lo) , | + |* |
| } 1 L_
L ; \ = L
Litt Lit pois} Lirisl rill Litt wil
z= - 3s € § g= =s 5 &
(28s/w) (9as/us) " 3 s S 5 (998/u)
4414 [001148 44140 M-3 (4) ybuads piers 444d 109148,
uolbay- 3 uolbay-3 * oysuboyy uoibay-4

prt yt tT

3

oc 3

B

(9as/w) ‘
Hud M-3
uo}bay-3

pot TTT

es
=
s
&

S 3

14) Hua play
oaubow,

0800

0000 0400

————+-— 29 November, 1968 ——

2000

+28 November, 1968 (75° W Time)

1600

1200

0800

2
3
s
=
a

34


pTTrry

ift Dota Until 4 March, 1968

pttt

PT TTT]

Pry yr ray

wo

0800

Vi-g

Vio

0400

0000

2000

ca

1600

1200

TI

}+-_——14 December, 1967 (75° W Time) ———+—15 December, 1967

TIT] fr

No F-Region Drift Data Until 4 March, 1968

TTT]

TTTT TTT

0800

2000

1600

0000
, 1967 (75° W Time) +16 December, 1967 ——|
16

1200

at At rT 3

a i i
0800
+5 December,

a |
pititisit} Lireitiiiis Git diidits ritiliiis| Lire J Loves Mabel |
s = s =
* * 8 $2 8 58 = a ey UU UBUD
(98s7us) (98s7w) Ed co] & Pi (98S/W) (9es/w) ] = S Ri
43144 [DIIEA, 4340 M-3 4) yibuads pial HUQ [OIE 4Ud M-3 Ga) ybueHs plal4
uojbey - 4 uolbay-3, olyaubpyw uolbay - 4 uoibay-3 oyeuboy


PTT Ty TTT 71 Perret
a

prrrryp rity) fTTTTTTTTT]

port TTTT TITTY

aE

Time) + 22 July, 1967 |
8

i jt i
0800 1200
[21 uly, 1967 (75° W

8
L & 3 L ©
4 HH —
a ce ns: Senn SO ae a an
Bel BOL
H es |
$3
doa L_
0
; 8 H r 8
® 4s 2
Lg vPy és
; = 1 ro
Lo + 4 Lo+
= =
| 5 4 L 5
2 = 2
= By té
S > 2 =
ee es BT) & pe
a ne ee ane EY OU 0 ae
& g Bs = @
fou i. b Po
| 3 432 L 2
L | & L
i) 2
L 4 os L
3
| 4 3 |
L e®@ 4
iy |
L no L 4
rittisit) Lira mot} Li Niriitidiig pooetiticd Loree teeis | Love Noi tails
e o 3 e = 2 = S
# 8 #2 8 § g= & Bg $5 € & &
(9as/w) (98s/w) Eo = a i (99s/w) (98s/w) as = S
4$44Q [DOH4eA, 440 M-3 4 ybueys pjal4 444d [DOH48A, 440 M-3 f4) ysbueys platy
uolbay- 4 uoifey-3 oyaubbyy uoibey -4 uoibey -3 oneubpy)


0800

0400

0000

2000

1600

1200

TTT TTT. TTTTYyTIrtyT TTTT T TTTT TT TTT TTTTy Tyr
[ 1 | 1 f s poy } opm T 7]
8
i. >
8 Sa —
ee
33
S$ 3
De
3+ L
gi [
No
a.
a nD Sak
Bo fb Pe
°
ie) J.
et
[ eB | ;
| go oL |
EI
3 |
7 < r |
r 5s r |
[ [ |
r L
|. Ae |
roottvise) Liptay bowtiihiihts. rittisiel Liriitia
B - 38 = gS 8 a 8 8 = BB ©
(98s/w ) (98s/w) ‘s x Pi S (99s/w) (998/W) s x S &
HQ [B91 149A, HH M-3 4) yjbuays plats 444d JOO 48, Hud M-3 4) yibuadjs pjaty
uoibay- 4 uoibey-3, oyauboyy uolbey-4 oyaubpy

uoibay-3

f/————— 2 August 1968 (75° W Time) ——_———13 August, i968

3!


TTT

TITTY] TITTY]

|
+

0400 0800
20 June ,1968

000

2000

3 +
|}-————19 June, 1968 (75° W Time)

1600

1200

L 9
potty) Lod Lit
8 = Bes s 2s Z Ss  gs&
* BS 8 3 S
(98s/W) (99S/w) “8 s 5 5
AJC [DOH 4aA, 44d M-3 4) ybuens plals
uolbey- 4 uoibey-3 oneubpy

TTT

B

TTTTTTTT]

Listilisii)

o BS

(998/W)
434 [DON48A,
uoiBay-4

ft TT

(99s/w)
wud M-3
uo}Bey-3

500

0

500
28,100

*

=
2 8
3 2

(4) yjBueds pjaty

o1auboyWy

2000 0000 0400 0800
2 July, 1968

1600

1200

i
-

}+-————- | duly, 1968 (75° W Time)

28


TTTT

re |

| Drift Data Until 4 March, 1968

H
i

or
i
i

T

T T T H
i
No F-Regi
fi
H

_

TTTT] PUTT Ty rrTr yr) prt PUTT yr Ty T
|

s
3

S

Littl
2

“

(9asyw)
ASU [09H] 49,
uoibey - 4

Loositiiii)

=

3B

S

(oes)
444 M-3
uo}Bey-3

3
e

0800

t
0400
T July, 1967

I 3S
2000

i
1600

TT

TT
No F-Region Drift Data Until 4 March, 1968

THTTyPT TTT] prrrt

\

i

re
Han

4
t
i

0400 0800

_
8 July, 1967

1
ms
T

_—_t
2000

FE
[4 i jo
1200
}+—_——_-7 uuly, 1967 (75° W Time)

Lt
1600

28,100 —

arian
0800 1200
[+ 6 uly, 1967 (75° W Time)

bititiriitiy titttiisi) Loriitiiist) Lil s
= = B = S
2 2 & ® eS gs 8 3°
8 S oi (90S8/u) (98S/u) xs Ss S ee
4) yibuais pjal4 HY |DOIHEA, 40 M-3 Co) yibuars piely
‘o1eubDA) uolBay - 4 uol Bay -3 oyeuboy,


FARLEY, D. T., 1970 Equatorial Spread F: Implications of VHF Radar Observations,

B. B. BALSLEY, J. Geophys. Re -
R. F. WOODMAN and + Seophys. Res., 75, 7199-7216.

J. P. MC CLURE

SUGIURA, MASAHISA and 1966

A Model Equatorial EL j . .
JOSEPH C. CAIN ‘1 ria. ectrojet, Bs Geophys. Res., 71, 1869

TARPLEY, J, D., Jr. 1969 Tonospheric Wind Dynamo, Ph.D. Thesis, University of
Colorado.

WOODMAN, R. F. and 1969 Methods for the Measurement of Vertical Ionospheric Motions

T. HAGFORS Near the Magnetic Equator by Incoherent Scattering, J. Geo~

phys. Res., 74, 1205-1212.

WOODMAN, R. F. 1970 Vertical Drift Velocities and East-West Electric Fields at
the Magnetic Equator, J. Geophys. Res., 75, 6249-6259.

|
i

|



0800

0400

0000

+ 2 December, 1967 ——_|

2000

L
1200

[20 December , i967 (75° W Time)

0800

TTTT TTTtT l f TTTT TT mT] | TTTT | TTTT T TT 7 TTT TT TT] [ TTTT TYTTT l ft TTT T TTTT T T
LL Aan al |
8
S - | +4
©
aL | |
5 coated Ge eee A ena At Sane |
se | |
= 5 . +
28
8
fa) - | 4
8 L | 4
iim
| ¢ > » |S | ¢ a |
r 2 4 | & J
- < | - o£ 4
| 2 4 ro3 4
| 8 Vise L 8 i
= SE =
a a a L§----|
tren Gonos n v re ono nn pon nnn n nnn enone ee 2 == - = mao § 4
- 4 ° - &
fied 0 io é
L * 4k | ¢ 4
3 en 2
2 430 LL 2 +43
L 2 L 9 4
+ 5 = m
= 2 L | 4
8
| | 8 L 44
fa}
} 4B om ie
» /=2 Pa
L \ L H
pioitiritt Lorie tiiis boli tits pot) DR | mn
Fey "8 a BE E EB Be ag Se tee g
(o9s/w) (98S/w) s s be =<] (98s/W) (99S/u) “3 S aS BS
4d [Od 48A, HUG M-3 4) yybueas pats Hug [DoH48A, WG M-3 ce) yjbuaas pjels

uoibay - 4 uoiBay-3 olauboyy uolbay- 4 uoibay-3 oyeuboy

I7


14 July, 1967 (75° W Time)

TTTT TTTT TTTT TTTT ] T rt T
| | { i} ee port yr prrry PrTTy TTTTT ETAT]
8 y3
L. d 44 L
re es: my~ ------ ee td pone
a es a ae a ae
F ( we F
b . 5 ss
- i Wze3 7
L . : Los |
|
L i +4 L »
cy H s Ey
l ¢ ole, | ¢
+ & | | t 2
+ = = 44 L +
Ls ha i | 5
2 2
| 8 . js | 8
= sy ; R =
= < ate £38
ne nie 2 eines ie: hee ai e cs
pop \ corres ae an
bok J & Fe
| 3 H fight L 2
i 25
1 oO
| i 4 8 |
H 0 =
= H 4 a =
L g i 3
L : 43
. ] : ;
ab : i i. »-
otis) Ling mo Lr Nii s rititisiss Litertiriss | mois
es 5 88 5 gs € § §© =e = Be ° Bs 8 gg g8
{oes/w) (9asyw) a) xs x] ~~] (98s/wW) (998/W) ro] & 7 I
HUG 1DaIEA, Hud M-3 4) yiBuars plats HL DOEA, HUG M-3 4) yjbueys piety

uoibey-4 uojBay-3 oyeuboy uolbey- 4 uolbey-3 oneuboy

(5 July, 1967

7


poy poy] pot ToT TIT op TTT] py
f------~4-—-----~-------~-L --------------~--------- @} © ]=---------
P----- fy & en
[ ® L
seoL
L ES 5
| 5 L
LL s |
3+
| f 2
| | 3
8 es &§ 2
+ 8 Si +e g
tb 5 rs Fou
L---5 -- F a a nN A
H FF
Lf % |.
| ge ob 3
ZO s
| © L
2
z -
L. 2 L
| zy) + g
L a-| | _
ceitisitt Leristrrii} Lively Liolts portivit} Liviediriid Lol g
es 5 8g S 88 € § g© & > B38 * Be B
(98s/w) (9es/w) " 3 gS Bu Ps (98s/w) (988/wW) = & NX Ru
§Uq |DOJEA, 44440 M-3 404) uibuavis platy 444 [DOHEA, Wud M-3 yA*) UibuadS pray
uojbay-4 uo|bay-3 oyeauboy) uolbay-4 uoibay -3 oyeuboy

27 April, 1968

-}-————26 April, 1968 (75° W Time)

23


WORLD DATA CENTER A

Upper Atmosphere Geophysics

REPORT UAG - 17

IONOSPHERIC DRIFT VELOCITY MEASUREMENTS
AT JICAMARCA, PERU (JULY 1967 - MARCH 1970)

by
Ben B. Balsley
Aeronomy Laboratory
National Oceanic and Atmospheric Administration
Boulder, Colorado 80302
and
Ronald F. Woodman
Jicamarca Radar Observatory
Instituto Geofisico del Peru!
Lima, Peru "q

Prepared by World Data Center A, Upper
Atmosphere Geophysics, NOAA, Boulder, Colorado
and published by

U.S. DEPARTMENT OF COMMERCE
NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION

ENVIRONMENTAL DATA SERVICE
Asheville, North Carolina, USA 28801

October 1971

SUBSCRIPTION PRICE: $9.00 a year; $2.50 additional for foreign mailing; single
copy price varies.* Checks and money orders should be made payable to the

Superintendent of Documents, and orders should specify the Catalog order number.
Orders, remittances, and correspondence regarding subscriptions should be sent |

4 the Superintendent of Documents, Government Printing Office, Washington, D.C.
8402,

*Price this issue $.35 (Catalog Order Number C55.220:17) |



Upper Atmosphere Geophysics Report UAG-14, "An Experimental Comprehensive Flare Index and its
Derivation for 'Major' Flares 1955-1969", by Helen W. Dodson and E. Ruth Hedeman, McMath-
Hulbert Observatory, University of Michigan, July 1971, single copy price 30 cents. [Catalog
No. €55.220:14)

Upper Atmosphere Geophysics Report UAG-15, "Catalogue of Data on Solar-Terrestrial Physics",
prepared by Research Laboratories, NOAA, Boulder, Colorado, July 1971, single copy price
$1.50. (Supersedes Report UAG-11, June 1970.) [Catalog No. C55.220:15]

Upper Atmosphere Geophysics Report UAG-16, "Temporal Development of the Geographical Distri-
bution of Auroral Absorption for 30 Substorm Events in each of IQS¥ (1964-65) and TASY (1969)"
by F, T. Berkey, V. M. Driatskiy, K. Henriksen, D. H. Jelly, T. 1. Shchuka, A. Theander and
J. Yliniemi, September 1971. [Catalog No. 55.220:16]

Upper Atmosphere Geophysics Report UAG-17, “Ionospheric Drift Velocity Measurements at Jicamarca,
Peru (July 1967 ~ March 1970)," by Ben B. Balsley, Aeronomy Laboratory, National Oceanic and
Atmospheric Administration, Boulder, Colorado, and Ronald F. Woodman, Jicamarca Radar Observatory
Instituto Geofisico del Perd, Lima, Peru, October 1971. [Catalog No. C55.220:17]

USCOMM-NOAA-ASHRVILLR-10-20-71~~500



TTTT TTTT]ttry TT TT 7 TTT TPT Try TTT TTTTYy TT Try tt ir
LT lf s [ 1 J +f Thr
8
ad
& ea
a ®
= 6 |4
a
gs 43
a Iq 8
- 2 J | [.
3 Vy 3 &
[ ¢ i 1 (8 | ¢
r 2 P | t 3
L = ly J L =
g Soh z
[ 2 ¥ al [ 2
3 H 3
= a) fe fé
L & H » +4 t 4
FS aaa eneennneeneeeecnnees a ne oo BT fa 3-4
to rr i rs aan ga] = Ee
| ¢ fj ® FE
- 2 48 5 + 2
= 4 a }—
9 =
L 41 @ L
: 3
g
L 4+ 2 L
+
L. 438 L
| ~ L
L. et | L
vithiiii} Lisiritiriid | Lroooihiihts roittiieet Lepriteviit Loseitbiiiy
s Ss = = =
% rn 2 i 28 ee
(99s/w) (9asyw) x 8 Ss a (99S/w) (98S/wW) s 8 RS
HUG [DoWZeA, 4d M-3 4) yibuadys pats 444d }DOH IEA, HUG M-3 4) yibuaas pial
uolBay -4 uoibay-3 oyeubpyy uolbay-9 oueuboy,

t
0800

1967 (75° W Time) —————++——9 August, 967 ———_|

10

|} 8 August


TTTT PTET} PTTTT ETT rT frrrrp rrr tyr ry PreTyr Tey] prrrrpr rrr] prrtrytrt
L »48 |
. 3 : 5]
acc nn CS Wa =
r yy 5 74 2
=
‘ Ve:
L J i] a
}- | \ 4
1 H 44 |_
: rr el (8
[ € wf/BT fog
| 2 al [ 3
+ = +4 - =
_ 5 | 7 | 5
g 5 - g
L 38 = 48 } 3
L § 2 Ls
or) : e [8]
a 2 Qo
[é 2 [Le
L to a
9 iS 3
| & | 3
&
L + 8 |
9 ~
L 4 os L.
3
|. 44 3 L
oN
L 43 L
41s
| i: | | wo
boitdisiiy Litt dds rottirir} Lirittiiirt poids
ee, FR 6S £ & f 8 5 Re = & g 8
(98s/W) (9as/w) g c] Po i (988/w) (988/) fi &
AUG [O91 8A, 440 M-3 4) yybuays platy AJUQ |DOWIeA, 44d M-3 4) yibue.g plaid

uolbay -4 uo|bay-3 oneuboy) uolbay~4 uoiBay-3 oNeuBDy)

7

0800

1200 1600 2000 0000 0400
Time) ————+——— 4 August, 1967 ———|
9

[+3 August 1967 (75° W

0800


ee TITTY Tr tt] prt
[ zg L na 3
EOE 2
ol 8 foo
ee =
|. , Se + =
L 3 |
L. N L
| r |
' By s+ fF 3
[ fF Ls
|. f £ 2 3 } =
_ x & s
i - Sn Ct
a come Tp OUTS Se en ee
| a)
L | R |
t | Bo oF i 2
| aD |
L | 3 =
| =
1 3 |
eq
L ; & © L 8
tL. | | )
i
rithtirii} LiviiNiers} Lines | roritiiii} Liver tiiis 3
as S 838 5 B88 s es 5 “sg 5 S
(988/U) (988/W) "= s x (988/us) (98s)
4J44Q IDOI AeA, Hd M-3 A) uyibueds pjal4 HG [DEA Hd M-3
uoibey- 4 uolbay-3, olyeubpyy uoibey-4

uo|6ey-3

————+—_6 October 1969 ———|

[I October, 1969 (75° W Time)

42


prot]

0400 0800

0000

2000

(600

1200

+_——— 18 July, 1968 (75° W Time) —————+—- 19 uly, 1968 ———

Losi tiiis

0800

27,800

NS
4344 JO1A9 A, (A) yBuedg platy

HQ [O1H48A,

o

-500'—

(pasyw)

4140 M-3
uol6ey-3

0800

0400

2 August, (968

Lt
0000
a.
+

jot

{——+—_1—_4+—1

2000

30

4

Jojo} oj) it 4
1600

1200

_t

2—+—— 24+ 4. 0.

27,800 Lt

|} 1 August, 1968 (75° W Time)

0800

(4) yjbueds plal4


rit

TTT TTT TTT

rr a

pititiiit

3—+—4

TTTT]

0400
3 July, 1968

0000
J.
+
T

2000
T

No F-Region Drift Dato

1600

Lo Hl
0800 1200
+2 duly, 1968 (75° W Time)
T T T T

biiiiiiit|

ma

TTTT] (trTTyy

Litt

jitt

iw
S ro

aa
(99s/w)

4} [DOI EA,
uoibey-3

|
s
8

=
(998/w)

440 M-3
uoibay -3

27,900 }-—

(4) ysbuaag pyatg
*
oyeubpy)

s o
3S

8

27,800

(98s/us)
44l4q [DOEA,
uolbay -4

l
s
8

=

8

(988/u)
444g M-3

uojbey-3 *

oyauboyy

(4) yibuaas platy

0800

0400

0000

1200

I7 July, 1968 (75° W Time) a 18 July, 1968 ———+

29


i preempt T TTTT 0 T

| n-

L « +4 L 4-4
«
+--+ my -----------------}.-----@.-.|-4 aan H 9.

0800
T
3
1
080

T

+

it
0400

12 July, 1967
T
+
|
0400
13 July, 1967,

wi
+
as
0000
T T
Ver
1 i
0

A

iad
1

2000
T
!

2000

T

i
i
in
1
i
H
1
{
'
:
‘
H
1
1
1
i
'
t
1
Hl
1
'
'
'
i
1
i
i
H
1
i
'
\
F
1
T
Hl

T
1
1
gio
i
i
1
1
1
i
1
t
i
i
i
i
i
if
T
I
'
i
'
i
i
i}
i
iT
if
1
1
1
1
i
1
1
1
1
i
H
i
L

TT
No F-Region Drift Data Until 4 March, 1968
1
a
+
{_t
TT
No F-Region Drift Data Until 4 March, 1968
4
t
14

il
i
1
i
t
I
I
i
H
i
i
i
i
H
1
—TM),
1
i
1600

L
1600

i
0800 1200
+12 duly, 1967 (75° W Time)

T

3

Liit boii L Liit

TOT TT
0800 1200
-————11 duly, 1967 (75° W Time)
TT T_T

| | | cittiiiil pitititret foi corel Levee bare e lay
$= Be " Be g 8 s ° @8 ° #8 € &

28,100 —
27,800!
27,90
27,800

0
»-
(998/w) (98s/w) Ri (98s/wW) (9asyw) * x
434d JDOLEA, HHO M-3 (4) ysbuedys plats 44 [O91 49A, 4340 M-3 (4) yjbueds pjais

uoibay - 4 uo1bay-3 * oyeuboW) uoibay-4 uolbey-3 * oeuboy)


No F-Region Drift Data Until 4 March, [968

TTTTPT TTT)

PUTT PTT TT]

ptr

ao

(600

J}

2—-—_ 2-34 4.
jt |

0400
1968 (75° W Time) ————-++—26 January, 1968 ——|

0000

2000

1200

}--——25 January,

TTT] TTT Ty}

pitititiit Liiitiii! Lot Xvi lids roils
s 5 88 ° 88 g€ ¢€ g & © &B
(99s/w) Qvasyw) es] 5 <o (99s/W)
444Q [DD 489A, Hud M-3 (A) ysbuays pjet4 4440 1091 }48A,
uoibay -4 uoibay-3 * oiaubbyy uoibay-4

Lisi tiiii)

uoibey-3

fTrTy ttt] (PTT

4]

° 8

(oasyw) |

28,00

¥ oaubDy

1600

0400 0800
27 January 1968——

0000

es

2000

1200

se = &

Ud M-3 (4) ybuars pies

0800

20

+26 January, 1968 (75° W Time)


0400 0800

|} 30 January, 1969 (75° W Time) —_—3 January, 1969 ——4

0000

2000

PTTTYTTTT] frTrry rrr yy

[TUUTPTTTT Try

-----~-5] Po an ae wen nn nnn nn fe fan nnn nen ry
a
Ta u
3 a |
[_ s L 4
4 | ©
; | | |
L o- F wo
votttivis} Liriitiviid | | wills bitthitir) Lopes tiriy} Coppi dared Pils
3
8 = 8 = se 8 8 83 3 = Bs = es 8 8 8
7 8 Be = g eB Bs s S 3
(99s/w) (09s/w) & ] i] Ps (93S/W) (98s/w) gs & S PN]
UUG [DoE HG M-3 4) yybuays plats HUG [DINE 4440 M-3 i) yibuadig play
uoibay ~ 4 uoibay - 3 oyaubow uoibay -4 uolbey-3 oeuBDyy

0800

0400

| |2 February, 1969 ——|

1600 2000 0000

1200

}-——___ Il February, 1969 (75° W Time)

37


TTT]

aetna a
|

TTT

TT TT]

pUETTyTT tt

TTT

0800

e
7s

o
©
cy
=
&
2
5
ira
0
o
£
=
S
&
XK
o
©
®
S
&
2
3
its
a

t
1200

TTT

TTTT]

am

seer ee =

TTT]

Pry rp

Lites ti} Liars te) Ladd iis itil Ly root} Lil
- 88 jc" 88 8 8 = a Cc 88 5 B88 8
(98/1) (98s/w) “ 3 Pf nu (988/W!) (988/W) " = i x
434Q [D9 48A, HUG M-3 4) yybuays play MUG |DOABA, WMG M-3 (4) yibuayg piais
uoibay ~4 uolbay-3 onjauboy uoifay-4 uoiBey-3 * oyeubpyy

0800

0400

2000

0000
11969 (75° W_Time) —-—+——14 February {969 ———-|

38

1600

1200

0800
}/—_—_——13 February



TTTT

------L

T

TT

TTT NTT

ee eee

ag

LL I
L 3 -
¢ |
9
ee ae z
Sa nr Sl
| |
L |
|
positivist Liriitiiii)
s °c 82 > 8
(298/w) (9esyu)
§314Q [DOH IEA, 4340 M-3
uolbey -4 uolBey-3

PUTTryTr CTT

0400

W Time) ——_——-|__— 22 May, 1968 ——4|

0000

1200

+ 21 May 1968 (75°

Litiljtit

rot

(4) yibuaas pjiaty HQ [D914 49,

|
= 3
B
(98S/uw)) .
4§4Q M-3
uoibey-3

0400
4 June 1968

L

L

0000

+ 1+ 3
-

1

4

Lot
2000
26

Tt —2 +2

oe oe ee
1600

1200

PPS ors rt
0

}——_———3 June 968 (75° W Time)

moot lil
=

080

28,100 -—
8,001
27,800

s 5
(4) yibuadjs pals


in the F region. At F-region heights, collision frequencies are so low that ions and electrons
gyrate several times before they are affected by collisions. Thus, motions perpendicular to the
magnetic field are effectively Hall drifts of ions and electrons produced by the cross product of
the electric and magnetic fields. At Jicamarca the magnetic dip is only 2°, so measurements of
(nominally) vertical drift velocities can be taken as a measurement of the horizontal electric
field. The relationship between the drift velocity and the electric field is given by:

v= 10 E/B @

where V is the vertical drift velocity in m/sec, E is the electric field strength in mV/m, and
Bis the magnetic field strength expressed in gauss.

II, E-region measurements

The measurement technique for the E-region drifts has been coyered in a series of reports
[Balsley, 1969a,b; 1970a,b]. Briefly, the data are obtained by determining the mean Doppler shift
of oblique radar returns from a type of electron density irregularity embedded in the equatorial
electrojet, These irregularities drift with the electrons so that a measurement of the irregularity
drift velocity is equivalent to a measurement of the electron motion itself. The method is limited
to periods when the drift velocity is between about 50 m/sec and 360 m/sec (the ion-acoustic veloc-
ity): for yelocities below 50 m/sec, the irregularities are too weak to be reliably observed with
the existing radar system; for yelocities greater than the ion-acoustic velocity, the presence of
another type of irregularity (generated by the two~stream instability [Farley, 1963]) makes deter-
mination of the drift velocity somewhat difficult. It is possible to infer drift velocities up to
about 500 m/sec by making reasonable assumptions, and this has been done in the data presented here.
The above limitations are not too restrictive, since the observed drift velocities are less than
50 m/sec usually only for a short period when the electrojet current is reversing and exceed the
ion~acoustic velocity only for relatively short periods.

The possibility cannot be completely discounted that the E-region (as well as the F-region)
Measurements are contaminated during periods of intense spread F. For the E-region measurements,
the spread-F echoes could be received via a vertically-directed antenna sidelobe, so that the re—
sulting data might contain vertical motion of the spread-F irregularities. Although statistical
studies (unpublished three-year averages of E~ and F-region drift comparisons) show that this effect
is not important on the average, the reader should be aware of this possibility.

The E-region drift velocities which appear in this report represent time-average (2 minutes)
values of the average (over all heights) drift velocity in the electrojet region. The height aver-
aging arises because the mean Doppler shifts obtained from the oblique-echo spectra are a composite
of the shifts from irregularities over the complete height range of the echoing region (95-110 km).
Therefore, although the electron drift velocity is strongly height dependent within the region
[Sugiura and Cain, 1963], the resulting drifts represent a weighted average value for all heights.

The accuracy of the E-region drift measurements may be conveniently classified into three
divisions: (1) for velocities below about +50 m/sec the accuracy is probably no better than +20
m/sec; (2) for velocities in the range 50-360 m/sec, the accuracy is better than +15%'of the value
shown; (3) for velocities in excess of the ion-acoustic velocity (360 m/sec), the plotted values
should be considered only as indicative of the probable velocities (the only quantitative statement
that can be made for values in this category is that the drift velocity is equal to or greater than
the ion-acoustic velocity).

The electron drift velocity may be used to estimate a value for the horizontal electric field
responsible for the drift: Sugiura and Cain [1966] show that the electric field is related to the
drift velocity by:

fe = Ey(02 Cos 1)/B(a, Sin*I + 0, Cos?I) (2)

where V_ is the electron drift velocity (assumed to be equal to the irregularity drift velocity)
expressed in m/sec; 01 and 0, are the Pedersen and Hall conductivities, respectively; B is the
geomagnetic field expressed in Weber/m*; and E, is the imposed (east-west) electric field expressed
in V/m. For values pertinent to Jicamarca (B 2 27 x 10-°Weber/m*, and magnetic dip = 2°), and for
the most recent values of the conductivities [Tarpley, 1969], (2) may be written as:

E.

y = 75.9 x 10° v, V/n (3)
Data Format

All of the data presented in this report are displayed in one format: the curves representing
(1) the F-region (vertical) drift velocity, (2) the E-region (east-west) drift velocity, and (3)
the magnetic field strength (H trace) are shown in the time interval 0800 on a given day until 0800
on the following day (75°W. time), This format is adhered to even when only portions of a data day
are available, or when only one of the two drift measurements are made.



Publication Notice

WORLD DATA CENTER A ~ UPPER ATMOSPHERE GEOPHYSICS REPORT UAG
(Prepared by World Data Center A, Upper Atmosphere Geophysics, NOAA, Boulder, Colorado)

These reports are for sale through the Superintendent of Documents, Government Printing Office,
Washington, D. C. 20402. Subscription price: $9.00 a year; $2.50 additional for foreign mailing;
single copy price varies. These reports are issued on an irregular basis with 6 to 12 reports being
issued each year. Therefore, in some years the single copy rate will be less than the subscription
price, and in some years the single copy rate will be more than the subscription price. Checke and
money orders should be made payable to the Superintendent of Documents.

Upper Atmosphere Geophysics Report UAG-1, "IQSY Night Airglow Data" by L. L. Smith, F. E.
Roach and J. M. McKennan of Aeronomy Laboratory, ESSA Research Laboratories, July 1968,
single copy price $1.75. [Catalog.No. C52.16/2:1]

Upper Atmosphere Geophysics Report UAG-2, "A Reevaluation of Solar Flares, 1964-1966" by |
Helen W. Dodson and E. Ruth Hedeman of McMath-Hulbert Observatory, The University of Michigan, |
August 1968, single copy price 30 cents. [Catalog No. (52.16/2:24 I

Upper Atmosphere Geophysics Report UAG~3, "Observations of Jupiter's Sporadic Radio Emission
in the Range 7.6-41 MHz, 6 July 1966 through 8 September 1968" by James W. Warwick and George
A. Dulk, Department of Astro-Geophysics, University of Colorado, October 1968, single copy
price 30 cents. [Catalog No. €52.16/2:3]

i]
|
i
|

Upper Atmosphere Geophysics Report UAG-4, "Abbreviated Calendar Record 1966-1967" by J. Virginia
Lincoln, Hope I. Leighton and Dorothy K. Kropp, Aeronomy and Space Data Center, Space Disturb-
ances Laboratory, ESSA Research Laboratories, January 1969, single copy price $1.25. [Catalog
No, €52.16/2:4]

Upper Atmosphere Geophysics Report UAG-5, "Data on Solar Event of May 23, 1967 and its Geophys~
ical Effects" compiled by J. Virginia Lincoln, World Data Center A, Upper Atmosphere Geophysics,
ESSA, February 1969, single copy price 65 cents. [Catalog No. C52.16/2:5] i

Upper Atmosphere Geophysics Report UAG-6, "International Geophysical Calendars 1957-1969" by
A. H. Shapley and J. Virginia Lincoln, ESSA Research Laboratories, March 1969, single copy
price 30 cents. [Catalog No. C52.16/2:6]

Upper Atmosphere Geophysics Report UAG~7, “Observations of the Solar Electron Corona: February
1964-January 1968" by Richard T. Hansen, High Altitude Observatory, Boulder, Colorado and
Kamuela, Hawaii, October 1969, single copy price 15 cents. [Catalog No. C52.16/2:7]

Upper Atmosphere Geophysics Report UAG~8, "Data on Solar Geophysical Activity October 24~
November 6, 1968", Parts 1 and 2, compiled by J. Virginia Lincoln, World Data Center A,
Upper Atmosphere Geophysics, ESSA, March 1970, single copy price (includes Parts 1 and 2)
$1.75. Part 1 [Catalog No. (€52.16/2:8/1], Part 2 [Catalog No. C52.16/2:8/2]

Upper Atmosphere Geophysics Report UAG-9, "Data on Cosmic Ray Event of November 18, 1968 and
Associated Phenomena” compiled by J. Virginia Lincoln, World Data Center A, Upper Atmosphere
Geophysics, ESSA, April 1970, single copy price 55 cents. [Catalog No. €52.16/2:9]

Upper Atmosphere Geophysics Report UAG-10, "Atlas of Ionograms" edited by A. H. Shapley, BSSA
Research Laboratories, May 1970, single copy price $1.50. [Catalog No. 052.16/2:10}

Upper Atmosphere Geophysics Report UAG-11, "Catalogue of Data on Solar-Terrestrial Physics",
compiled by J. Virginia Lincoln and H. Patricia Smith, World Data Center A, Upper Atmosphere
Geophysics, ESSA, June 1970, single copy price $1.50. [Catalog No. C52.16/2:11]

Upper Atmosphere Geophysics Report UAG-12, "Solar-Geophysical Activity Associated with the
Major Geomagnetic Storm of March 8, 1970", Parts 1, 2 and 3, compiled by J. Virginia Lincoln
and Dale B. Bucknam, World Data Center A, Upper Atmosphere Geophysics, NOAA, April 1971,
single copy price (includes Parts 1-3) $3.00. [Catalog No. C55.220:12/Pt 1, Pt 2, Pt 3]

Upper Atmosphere Geophysics Report UAG-13, "Data on the Solar Proton Event of November 2, 1969
through the Geomagnetic Storm of November 8-10, 1969", compiled by Dale B. Bucknam and J. |
Virginia Lincoln, World Data Center A, Upper Atmosphere Geophysics, NOAA, May 1971, single
copy price 50 cents. [Catalog No. C55.220:13]



TTTTTTTTT] prt 2 PEPTTTUTT] fTrrryrr ery prrrryprrer prey
8 i . if
o _ fd
8 a Aaa Soutimoisstsc a
es | Ble
8 f HE
ra
3 r i
S - 4
el 10
ee of (48
ie L B44
F SE Ghteeiened Iain Weeieeaeeeeieemeeeee |
2 a Tt
= r 4
BQ + +18
co) L 4
= 0
L 3 L -
a2
2
[. 3 L 44
r Bo F 48
s is
L | LI
i: ~ mo
fa root} Lai 8 Lisittireed Levee tiriil Loree leiey uils
5 _ 8 i 88 a 8 _ 33 ° #3 8 3 83°
(98s/w) (98s/w) "8s E] x S (0as/w) (98s/w) "8 ES} N 5
43UQ [B91 49, 4340 M-3 ue) yybuads pjat4 HUG JOO1} 498A, 40 M-3 ce) yibuays plaid
uolbey-4 uoibay-3 oeuboy uoibsy-4 uoibay-3 oyauboy

————+— 18 October , 196g ——}

/+_——17 October , 1969 (75° W Time)

43


Drift Dota Until 4 March, {968

rititiiiy| Litirteii

TTTT TTT] prrttytttTy

PUTT yt 77

0800

0400

1600 2000

1200

0000
-}-—22 September, 1967 (75° W Time) ————-+—2 September, 1967 ——|

TTT TT TT]

No F-Region Drift Data Until 4 March, 1968

bititiriid

pitt

s © 8g ©
(das/w) (988/W)

4344 1091} 48,, 440 M-3
uoiBay - 4 uolBay-3

| it
S
3
2 5
(4) yjbuadys pla
o1auBoyy

s ° &

(288/w)
HUQ [DOH JEA,
uolbay- 4

s

B

(38S/W)
Ud M-3
uoiBey-3

Poy rrr yr

es
—
s
aS

a

se 8

s 8 &
4) wbuaas plat
oiaubow

2000 0000 0400 0800
—_—_+_ 25 September , 1967 —_-

1600

1200

24 September, 1967 (75° W Time

13


MrTTptrt Ty) prt prt TTT Tar

TTTTTTTTT] pretty rrr PETTITT Tyra
m4

o-

0800

0000 0400

2000

a
H
i
|
i
t
t
i
'
i
Jit io

1600

T TT
No F-Region Drift Dato Until 4 March, 1968
1
[3 October, 1967 (75° W Time) —————+—— | November, 1967 ———
T T T T
No F-Region Drift Dota Until 4 March, 1968,

1200

[tit {itt

é
8 = Bs = 3
‘ B

|
z= g g¢ 8 € &
(0as/w) (988/wW) xs 5 nS (988) (998/W) s 2 S S
444G [OO[L.8A, HUG M-3 oA) WbURUS PIaLy 444g [DdHIEA HHO M-3 64) BUDHS PIAL

uo}Bay -4 uo|Bay-3 oyauboy uolbay-4 uo|Bey-3 oyeuBbyy

0800

2000 0000 0400
15

1600

1200

-+-——3 November , 967 (75° W Time) —————+——— 4 November, 1967


TONOSPHERLC DRIFT VELOCITY MEASUREMENTS AT JICAMARCA, PERU (JULY 1967-MARGH 1970)
by

Ben B. Balsley
Aeronomy Laboratory
National Oceanic and Atmospheric Administration
Boulder, Colorado 80302

and

Ronald F, Woodman
Jicamarca Radar Observatory (JRO)
Instituto Geofisico del Peri
Lima, Peru

Introduction

This report is a collection of measurements of electron drift velocity in the E and F regions
of the equatorial ionosphere, made at the Jicamarca Radar Observatory (dip latitude =1°N). The data
consist of about eighty days of observations during the period July 1967 to March 1970, The measure-
ments consist of (1) the vertical component of the electron drift velocity in the F region, and (2)
the east-west component of the electron drift velocity in the E region. Other components of the
drifts have been measured but the data are sparse and have not been included here. The horizontal
component (H trace) of the magnetic field strength records of Huancayo, Peru, has also been included
for reference.

The purpose of this report is to make these data available to the scientific community. Com-
parison between these measurements and other geophysical phenomena should aid in the understanding
of a variety of ionospheric and magnetospheric processes. This type of data continues to be taken
at JRO from time to time. For information regarding the more recent data, we suggest contacting
either of the authors of this report, The data included in this report are also available in digital
form on magnetic tape and punched cards. Inquiries should be directed to the World Data Center A,
Upper Atmosphere Geophysics, NOAA, Boulder, Colorado 80302.

Data Description

I. Feregion measurements

The F-region drift-measurement technique has been described by Woodman and Hagfors [1968].
The method involves the determination of the Doppler shift of incoherently-scattered signals from
the F-region ionization when the propagation vector is directed normal to the earth's magnetic
field. (When “Looking” normal to the magnetic field, the Doppler shifts can be accurately deter-
mined because of the narrowness of the signal spectrum.) A presentation and discussion of the
F-region data is given in a paper by Woodman [1970]. .

The data presented here are five-minute~average values of the average drift velocity between
300-400 km. This is achieved by averaging together the five simultaneous drift measurements (each
one representing a five-minute-average value) obtained in the five separate height ranges between
300-400 km.

The accuracy of the drift measurement is determined primarily by signal-to-noise levels of the
Feregion echoes, This is affected by a yariety of factors (transmitted power, antenna size, F-region
electron density, etc.). Under typical conditions, the drift measurements are accurate to within
about 42 m/sec.

One major obstacle in obtaining continuous (diurnal) drift velocity measurements is the occur—
rence of equatorial spread F (field-aligned irregularities in the F region that produce anomalously
Strong echo returns). Spread F [Farley, et al. 1970] is a frequent nighttime phenomenon, typically
beginning after F-region sunset and usually lasting until about local midnight. The presence of
strong spread-F irregularities in a given region effectively precludes drift measurements in that
region by standard techniques. (Doppler measurements during spread-F conditions can be made, but
the results do not describe the average behavior of the ambient ionization.) If the irregularities
do not occur within the 300-400 km height interval, then the drift measurements can be made; if they
Se occur within the interval, it is sometimes still possible to obtain a representative value of the
true drift velocity by hand-scaling non-affected points at other heights. The reason that this tech-
nique is useful is that the F-region drift velocity is roughly height independent under normal condi-

tions [Woodman’ 1970}.

These vertical drift velocities may be used to obtain a value for the (east-west) electric field
1



TT TTTT)

iz

PTV yp Trt

0400 0800

[+9 danuory, 1969 (75° W Time) —————+— 10 January, 1969 ——|

0000

2000

1600

TTT]

PUTT TTT TT]

rot

0
| 4
go | J
= ¢ ¢ ©
lL. | L 4
voi dliiii) pedvisie} Liritisiil 3 reoititiit Lisi tisiid Lovet itil |
Puy 8 oe #2 & & S 8 Be = ae EB &€ &
(9as/w) (9as/w) ' s = 5 Pd (998/W) (vas/w) s 3 S 5
$$ [DONEA, 40 M-3 4) yibuads pars AUC DIIEA HY M-3 4) yibuays play
uolbay - 4 uojbay-9 oeubow uoibay-4 uolbay-3 oyeubo,

1600 2000 0000 0400 0800

1969 (75° W Time) —— || January , 18969 ———|

1200

j-——_—_ 10 January

0800

36


prTr ry tty] PTT Trt] pry Tr ee
e
L 08 |
foo) [-------p ------ BL
§ aires te eeeneaeeneerien bee
sB oL
ea
ie) J
a
21 [
s
ge |
£
e
Jp = po—---
wenn gee b —-)--
n
3
Lao
© 2
@ =
=
L 4) 2 |
- 48 & - t t
L if . i | i
| i b | L
dotted) dit didi prtitiiris fitis} Lisi
rr 2 2 2
(998/w) (Qessw) x md S (ves/w) (vasywy s Pe
HQ [DOSA, BUG M-3 4) yibuanis piety 4444Q DOILEA, 440 M-3 4) yibuaas pat
uolbay-4 uoibay-3 oyeuboy uolBey- 4 uorbay-3 oyeuBDy

0400
29 April, 1968:

0000

2000

1600

i
1200

|} 28 April, 1968 (75° W Time)

27,800
0800

24


«



Vieg

E-3—+—4

Lit

puri

0800

0400

0000

2000

4

0800

pone nee enn. no 2a f------ === -------- 3 =

| G

Vi-g'

1600

4200

f}-———I3 August 1968 (75° W Time) ————-+——14 August 968 —-_—

Letortiriid Liniilivy

8

(99s/w)
HQ JOO! LA9,,
uoibay~4

28,100 -—

(4) yjbuexs play

0800
ors

3
3
fa
SN

ASQ [DON4aA,

= ss
(0as/w) S
40 M-3
uo}Gey-3

x64) Wbuans plats
oyeuboyy

0400

5S? W Time )————-}.— 14 November i96g——|

0000

2000

32

1600

1200

+13 November 1968 (7



i

PTT TPT TTT] fr rtry try prt

| b

0800
0800

0400

0000
1969 (75° W Time) ———+-———-31 May, 1969 ——4
~T TTT T T

0400

f+ 5 August, 1969 (75° W Time) ———_—-+— 6 August, i969 ———|
4)

0000

2000

2000

1200

es
r 3 r
r- L
L rz L
2
[ 7
|. 8 L
oe | Loi Wi | Li | corttiriet Lepittiiiyd Loti l
es = Bg ° Bs = @ 5 “sg s B28 2 &
(9as/W) (9as/w) a) (9as/u) (98S/W) 8 s S
HUG jDOWEA, 4uUd M-3 4) YyybueAls pyaig HG 100} 48, 444d M-3 4) yjbueds platy

uolbay-4 uoibay-9 oyaubow uoibay - 4 uolbay-3 oyaubo

1600


-|

pitty

0800

—Vi-o
0400
19 June, 1968

0000

2000

e7

| No F-Region Drift Data

1600

{600

. 1968 (75° W Time) ———-—-++— 5 June, 1968 ——_

1200

}_____. 4 June

1200

00

f+ |8 dune, 1968 (75° W Time)

Lroiittisiid

08

100

8,000 -—

28,
27,800

(98s/w)

Ea 5
IDO 4eA fA) uybuaas HUQ |DO1sEA, (A) ypbuaas piaiy


TTT]

Lititiiiys

prot

TTT yay

s-|

0800

L
0400

- Lt
2000 000
}-———— 9 August, 1967 (75° W Time) ————+——- 10 August, 1967 ——

TITTY]

No F-Region Drift Data Until 4 March, 1968

rittisiid

}iit

\
|

rit

Paty] ptt TTT Tyr
t4

ss’

SS;

ima
B

(99S/us)
441UQ 129148,
uo}bey-4

s
s
3B

° =
(288/w)
HUQ M-3
uoibay- 3

7,900 |-—-

rlins
s
=

5
x4) yibuaS plaid
oyauboy)

Ss
3B

L
= ae
2B
(998/W)
Hug 19449,

uoibay- 4

(988/W)

440 M-3
uoibey-3

3

27,8001

|
3
a

(A) ujbuaas
*
oyeuboyy

Plats

0800

0400
18 August,|967

1200 1600 2000 0000

0800

|} '7 August,I967 (75° W Time)


TETTy Terry perry prep TITT TITTY
| s48
18
L Jon L.
©
a Aen RO NO CS
[ Ee ee
L 486 L.
2a
3
|. 4+ 8 L.
L | *) SL
[ 8 | TI [ 3
} = 48 L 2
8 “ g
[ = 7 f =
} = | +4 . =
= i =
. 2 ,- 3
2 Ps “ =~ 2
L 8 * 42 Q | 8
L » °F io §
=  Na cui ba = as
é gw R |. é
rot q na aL
| 3 +48 9 }- 2
LL i g Ir
| 4 ¢ L
2
L 44 8 L
L j2e +
mI Nw
| + | L
rititirii} Lira mot Lon Pris boirtisiis
8 _ 38 ° gS 8 g 3 8 © 8
(pas/w) (2as/w) ‘8 = S S (998/u)
44440 1091 HUQ M-3 64) ysbuans plaid 414d [DOHA
uolbay-4 uoibay-3 oyjauboyy uoibay-4

prt

3 S
(998/w)
Wud M-3
uo}Gay-3

TITTY]

TTT

fom

Ty

0800

3-+—6.
jo}

-
I
iL

0400

, 1967 (75° W Time) —————+—— 3} October , I967 ———|

1600

1200

0800
}—————30 October

28,100

gl
2 8 8

2

64) wbuaNS Play
oeubDy

14