UNITED STATES DEPARTMENT OF THE INTERIOR

GEOLOGICAL SURVEY

PRELIMINARY GEOMAGNETIC DATA COLLEGE OBSERVATORY

FAIRBANKS, ALASKA

v FEBRUARY 1984 OPEN FILE REPORT 84-O3OOB

T H I S REPORT WAS PREPARED UNDER THE D I R E C T I O N O F JOHN B , TOWNSHEND, C H I E F OF THE C O L L E G E OBSERVATORY, W I T H THE ASSISTANCE OF THE OBSERVATORY STAFF MEMBERS: J n E , PAPP, E I A , SAUTER, L I Y n TORRENCE, P n A , F R A N K L I N AND I N COOPERATION W I T H THE GEOPHYSICAL I N S T I T U T E OF THE U N I V E R S I T Y OF A L A S K A , THE C O L L E G E OBSERVATORY I S A PART OF THE BRANCH OF GLOBAL SEISMOLOGY AND GEOMAGNETISM OF THE UaSn GEOLOGICAL SURVEY 1

Explanation of Data and Repurts

Magnetic Activity Report

Outstanding Magnetic E f f e c t s

P r i n c i p a l Magnetic Storms

Preliminary Calibration Data and Monthly Mean Absolute Values

Magnetogram Hourly Scalings

Sample For11,at for Normal and Storm hhgnctoerxams

Normal Magnetograms

Storm Magnetograms (When Normal is too disturbed to read )

Ul l FGF OBSFRVATOSY PRFI IMIPlASY GFOMAGNFTIC DATA

W I A N A T I O N OF DATA AND REPORTS

INTRODUCTION OBSERVATORY LOCATION

The preliminary geomagnetic data included here is m a e avai iable t o s c i e n t i f i c personnel and organizations as ? a r t of a cooperative e f f o r t and on 2 6ata exchange bas is because of the ear ly need by some users. To avoid delay, a l l of the data i s copied from o-iginal f o m s processed a t the observatory; therefore it should be regarded as preliminary. Inquir ies about t h i s report o r about t he College Observatory should be addressed to:

Chief, College Observatory U.S. Geological Survey 800 Yukon Drive Fairbanks, Alaska 99'701

Requests f o r copies of the magnetograms except f o r the current month should be addressed to :

Yiorld h t a Center A NOAA D63, 325 Broadway Boulder, Colorado 80303

GEOMAGNETIC DATA

Normal, Storm and Rapid Run magnetogrms and approsr ia te ca l ib ra t ion data a r e processed da i ly a t the observatory and a r e ava i l ab l e f o r analys is or copying. Also available, a r e mean hourly scalings, K-Indices, se lec ted magnetic phenomena repor ts and on a r e a l - t h e bas is a r e recordings from a 3-compo- nent f luxgate magnetometer and F-component proton mgnetometer.

The College Observatory, operated by the U.S. Geological Survey, i s located a t the University of Alaska, Fairbanks, Alaska. It i s near the Auroral Zone and the northern l i m i t of the w r l d ' s g rea t e s t earthquake b e l t , the circum-Pacific Seismic b e l t . Although the observatory's basic operation i s i n geo- magnetism and seismology, it cooperates wLth other s c i e n t i s t s and organizations i n areas where the f a c i l - i t y and personnel can be of service.

The observatory is one of three operated by the USGS i n Alaslg. The o thers a r e located a t Barrow and Si tka .

The pos i t ion of the observatory s i t e i s : Geographic l a t i t u d e ....... 64'51.6'N Geographic longitude. . . . . -1Z')O 50.2'W Geomagnetic l a t i t ude . . . . . .+64.@ Geomagnetic longitude .....* 256.43 Elevation ................. 200 meters

:Eagne?ic Act iv i ty The K-Index: The K-Index is a logarithmic measure-

ment of the ranne of the most disturbed comwnent (D or H ) of the geomagnetic f i e l d f o r e ight in tervals beginning O00QO300, 0300-0600.. .2100-2400 UT. I t i s a measure of the dif ference between the highest and lowest deviation from a smooth curve t o be emected f o r a comuonent on a magnetically quie t day, within a ti-ree hour in t e rva l .

The Equivalent h i l y Amplitude, AX: The K-Index i s converted i n t o an equivalent range, ak, which i s near the cen te r of the 1imitir.q gamma ranges f o r a given K. The average of the eight values i s ca l led equivalent d a i l y amplitude AK. The u n i t 10Y has been chosen so a s r,ot to give the i l l u s ion of an accuracy not j u s t i f i ed .

The schedule for converting gamma range to K , and K t o a k i s a s follows:

Gsmmn Range K - Index - ak O < 25 0 0

3 7

15 27 48 80

110 2L 0 LOO (ICY)

The Mafpetic Daily Character Figure, C: To each Universal day a character i s assigned on the bas is C=O, i f it is quie t ; C = l , i f it i s moderately disturbed; C=2, i f i t is g rea t ly disturbed. The method used t o assign characters a t the College Observatory is based on AX a s follows:

AK Range C 0-11 Ti

11-50 1 5Dc 2

Routine assignment of C was discontinued a t College on January 1, 1976.

Selected Phenomena & Outs t and lz ?Aagnetic Effec ts R i o r t o January 1, lW6, the Normal and Rapid

Run records were reviewed a t the observatory fo r selected magnetic phenomena and the events i den t i f i ed were forwarded t o the IUGG Gomission on Magnetic Variations and Disturbances. This was discontinued on January 1, 1976, but a report on Outstanding Ehgnetic Effec ts i s prepared monthly f o r t h i s repor t .

Pr inc ipal Magnetic Storns Gradual and sudden commencement magnetic d i s tu r -

bances with a t l e a s t one K-Index of 5 or grea ter , which a r e believed to be par t of a world-wide disturbance. a r e c l a s s i f i ed as pr inc ipal magnetic storms. The time of the storm beginning and ending; d i rec t ion and amplitude of sudden commencements; period of maximum a c t i v i t y ; and storm range a re reported. Monthly repor ts of these data a r e forwarded t o the World Data Center A i n Zoulder, Colorado.

Magnetogram Hourly Scaling's Magnetogram hourly scalings a r e averages f o r

successive periods of one hour fo r the D, H and Z elements. The Value i n the column headed "01" is the average fo r t he hour beginning 0000 and ending 0100. Note t h a t the values on the scaling sheets a r e i n tenths of rnm with the decimal point srnizted. The user of these sca l ings should keep in mind tha t the tabular values a r e hourly means and i f he i s interested i n the deta i led morphology of the magnetic f i e l d , he should r e f e r d i r e c t l y to the magnetograms.

k ~ e t o g r a m s The normal magnetograms in t h i s report a r e repro-

duced a t about oneIthird the s i ze of the or ig inals . Preliminary base-line values and sca le values adopted fo r use with the o r ig ina l magnetograms a re included. For days when the magnetic f i e l d i s too i i s turbed fo r t he Normal magnetogram t o be readable, Storm mgnetograms a r e reproduced.

Absolutes, Base-lines and Scale Values To determine the absolute value of the magnetic

f i e l d from the hourly means or from point scalings t he following equations should be used:

D=EL,+d.SD; H=++h*%; Z=B '2-3 whehe D, H and 2 a re absofute values; $, BH and BZ a r e base-line values; SD, % and SZ a r e sca le values; and d , h and z a r e scalings i n mill imeters.

U. S. DEPARTMENT OF COMMERCE ijuAA 76-133 NATIONAL OCEANIC AND ATMOSPHERIC ADMlNlSTRATlON (9-72)

MAGNET lC ACT l V l T Y (Greenwich c iv i l t imr, countad from midnight to midnight)

I K-INDICES

OBSERVATORY

COLLEGE, ALASKA

I TIME SCALE ON MAGNETOGRAMS

SUDDEN COMMENCEMENTS

24 1 d 16 h m

POSSIBLE SOLAR-FLARE EFFECTS BASED ON

INSPECTION OF GRAMS ALONE (WITHOUT

R E F E R E N C E T O D A T A FROM OTHER SOURCES)

16 1 d

APPROVED JOHN B. TOWNSiXEND, CHIEF, COLLEGE OBSERVATORY

O B S E R V E R I N CHARGE

N O A A FORM 70- is* SUPERSEDES c a t s FORM a t 5 * U.S. GOVERNMENT PRINTING OFFICE: 1973.761-847

K S C A L E USED:

LOWER LIMIT FOR K = 9.. . . . . . . . CURRENT SCALE VALUE... . . . . .

LOWER LIMIT FOR K = 9 ... .. .. .

B E G IN

d 11 m

END

d h r n

SCA L I N G S AND COMPUTATIOHS HAVE BEEN CHECKED.

D

675.7 3.72

2510

X H

322.2 7.76

2500

(rnm

(Y/rnm)

(to nearest 10Y)

Data from Individual Observatories: PRINCIPAL MAGNETIC STORMS

COLLEGE OBSERVATORY, COLLEGE, ALASKA February 19 - 8d

I I

WDC-A FOR BOUR-TCRRE.TRlAL C W Y S I W L N V l l l O N M l N T A L DATA S IRVICE, NOAA 8OULDEII. COLORADO 10101 U .S.A.

Ranges UT End SC - I

I D(') I

. .

. .

P1.x.

day

04 05

14

amplitudes

H(Y)

I .

. I

Z(Y)

a +

I .

3 hr - index K

( 3 hr - period)

3 , 5 , 6 4

5

K

6 6

7

COLLECE O E E R Y A T ~ , c o w , W K A -- PFELIWXAKY C ~ O R DATA FOR: FEBRUARY 198y

RORHAt NkCNETOCRAPB

COMPCmErn

D

H

CALlBRATION 'PERI(ID'

2

B A S E m

37" /&.'9 &C

/a657 d

FRLW

0000 ~ , 7 , 2 -/-By

00- U.7, 2 -/-BY

SCAZE V A U E TO

2400 0.z 2 - 2 9 - B y

#OO U.7 9&2?- By

/. L / M ~

dm0 u.Z. 2 -i-Sr/

3.7~/m?

s m MAGRETOG-

78 ~/h@

U.T. 2-)9-BL/

C m P c m m

D

H

z

7;G ~ /m&

CALIBRATIDlO

55/83 f

PeRfM,

WID RUlP H A G m R A P B

BASELIRE

d Y 0 2 % k ~

/0770 Y

&40?s,

FROH

aom 12.7; 3 -/-BY

P b m U.T,, - 2 --/-8q

0066 v.7: 3 -/-BY ,

SCAIE VMBE

c(13PONEm

D

B

z

M

dyob 0. T, - 2 -211-8q

~ Y Q O C1.q 2 -2 9- 84'

9400 o . ~ 3 -a-BL/

?P/mm dS!&f/m&

MmTHIx MEAN ABS0U.m VAUlEs*

D H Z

/ s ? a ~ 5 5 3 6 L b-= * C ~ D F R ~ Z E f l Q ~ T ~ W J R T R ; ~ .

nNs usell: m - 6 - 7 - B - 7 , /=z 1 , /7 , /Y , - a0 22

43, ? y/k&

Y8,o 6/m

CALTBRATIW

SCAIE v m mXOD

ma4 TO

1

1 )

1

021320 1327 320 172 2q2

01 -

a 3 6 7 3f3

303 274 283 199

p , . ~ l ~ l . . ~

158 1391 240 1207

293 309

303 302 303

194 I

3118 327 2112

0s - 316 380 2%

318 297 321

238 308 370

233 329

289

3/3 297 311

280 300

c...-;I~.

=

Pa

)O

1 1

3/7 328 / ~ 7

lOMrHCY YE** 1 3 3 ~ O'T's r 'rM On-

btrr..l Bs~e-l ime 5c. te rJ Sigailic.at ponim d d ~.gneii.c rt-

Begiaaial Y n l u V.ilr b m imrerpohwd. <> m e e d di *hc.t fa p n

No record; or a- r.lut* = d l d b a n . il v . 1 ~ i*

m-nikbk * m u * d I... c m r * m .nti-trd

6.1q n r d . fa .:.k# prr

* * r i * d LI S*m Map&., e n - 4 R-l Ygl.

CnZCm LO OY

S*UU¶ MS. wnwro mv

N M C U L D .I

U A L C O **

320 181 19q 309 374 290 332 305 277 263

27-57 300

317 307 300 183 287 294

mnd

i

3rlG

303 380 1335

JEq £AS

ZfP

LYT

=303

300 n283

306 1.305

35Y 272

303 311

3q8 2r19

315

324' 306

291

306 291 317 175 301 293 398 2 6 0

286

3.92

2 8 9

302 282 190 311

280 302 268 300 256 284 J ~ o 366

300

376

256 296 167

281J 2 y7 293 206 39, 241 278

- 11

15

l a

14

297 267

3 0 , 30q 255

164

297

39.5

256 3 /8 300

3/5 306 303 309 1 0 1

1 2 0 246

3/8 3 ~ 7

m p r l . 5

-261/ g Y 172

3Yq 293 / 9 5 305

i s 2 2 0

4.393

298 367

301 306

2.54 166

a 9 2 8 8 288 383

311 303 2.YB 307 297

2 8 5 309

278 306 2GB 298 252 37L/ 351/ 317 277Y

3/2

m

11

310 2 ~ ? / 1 ~ ' % 7

330

E . 2 6 3

308 310

5183 296

3 0 Y

343 32% 306 299 213 289

387 = Y ~ L

331*411*3~/3 30032G

3071303 330

307

/46

3 0 7 3 0 3 ] 3 4 /

229

1 . 2 9 3

1 9 3 0 5

284 189

287

3YL/ 3 4 ~ 7 ~ 2 7 4

324 zzo 192 3 l l

238 174 3 0 5 298

202 1/59

2.33

303 297 3 C 380

352 260 322

332

26Y 234 310 41%

38'1' 3 s 30q 220 3 4 1 9 0

3 Y o

~5 273

337 33Y 218 334 306

317326 398 473

I i -IU..:

338

338 427 5Y3

a4

367

310

( ) he~po1.t-d Scaling ==.mi. kc.-c

328

421 381 303 3 0 1

2 9 7

x 3 0 o

355 46(CY 383

304 337

578*570Y&507*~9

33Y

307 334 3 ~ 7 316

2 7 0

277 152

317 331

197

5 0 9

5%

337 "350 468

272 287

2 3 Y 261 301 27.5

u o * m c y

316

*a8

363

3111

248 361 ZL/o

32 /

300 310 338 341 317 256

371 238

3261°a

317 1 (11

4/27

270 305 280

fa

29

M

11

3 L z 353 2q+"

338

353 372

364 352 504 359 352

28q 290

137

Q

O-I

lo

l1

3/6 513*531Y

3/1

323*363*@37 381

185-

307 363 3LI

280 332

333 358

310 "EL23

466

370 410

351 348

316

336 31-1

308

7587 790.4

854.3 A

333 291 180 %2

239 303 3 7

310

331 318 381

312

IGI 292

308 306

31q 350 329

2 7 Y

335 353

3q3

376 3q3 352

357 328

502

417 3q2

1587*3171

308 338

6 7 y 8 I 4

330 353 286

336

319 3 3 r l 360

468 ?48q1528

334 317

32q 310

l a

595'539*5/0

3/3 163 31y

703 307 306 376

333

350 391

313 369

349 713

L/33

387

29Y 35'0 Y13 379

318

3 ~ 3 ~ ~ 4 332 316

387 333

rr

l*

381 314 313

3/54' 28y 3 1 1

318

7/18 7919 7713

383 324

~ ~ ~ j ~ . 5 ~ 5 * 5 ~ * ~ * ~ 9 0 ) * . ~ 7 ~ * ~ ~ ~ y

311 338 313

YI I

I36

fiq2

J f / q '370 1

rum 133423/

418

3oq 368

339 341

348 664

350 413

313 31.6

360 3 5 5 298

333. 299

421

362

359

36lf 353 330 342

4 1 1 331

430 313

1 * h 1

1 * 1 3 ~

393

427 311

2f8 3Y4 323

31q

3 3 Y

318 3 s

&/8*4%

6 0 1 * ~ _ 3 6 1

347 37q 378 3q6 3.55

3/q

352 333 33L/ 331

"

3/4 308 311

2 G L

278

* d l / 390

330

311

*a/ 7 3 3

614

3 4 /

3/7 372 36I 3G1 373

365 382

420 .?30

246 383

3 1 1

3118

307

305

176

408 333

330

6.52

-317

388 378

349 279

33/ 344 348 279 301 408

309 296

384 262

390

310 377

3Jo

331 325

S 8 351

373137~\232 308 )182 12~0

/LV 386

199

31q

7 6 4 5 7802 : 79q5 7 Y 8 7 7320

301

322

344 417

331

370 332 337 372 400

3.40 380

311 1336 297 1331

345

5u593y4*373

331 289

3/5 322

307 2 l o

370 379

7615

76 1 9

374 278

33L 39/ 347 171

30 378

96

/90

303 301 289

290

3581358

2qc 321

217

306 280 296 238 296 230

8490 9001

7703 7369

3 - f ~ 451 390

448

346 1 q 1

L//o 751/*509 401

371

308 -390

3ft' 220

2q2 If34 372

209 274 22-3

8133

171

275-

7456 7 L 1 5

7338 750/ 77/9 87t9

737f 80l8

;2N

300 7636 7212

FEB 7.19E4 I I

FEB 8 1984

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20 24 U.T. 4 16 - - - - - - ---dl L-V ---.-

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COUEGE. A U S K A I l l I , '

L a t FEE 9.1484 FEB 10. 1W *

20 24 U.T

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COUEGE, ALASKA

FEB ii. iw I I

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-.. -- 10 24 U.T. 4 8 12 1 b

&*rS.e--*-. -

-.-

~ o h ~ . A ~ W A FEB 12, lsaP

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24 U T 4 I3 12 16

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l i I l l I l l I 1 I I I I i l l I I Y I I l l

COLLEGE, AUSKA I FEB 27, 1-

I I FEB 28.1984

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20 24 U S 4

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STORM MAGNETOGRAMS