Gubbins D., Herrero-Bervera E. Encyclopedia of Geomagnetism and Paleomagnetism

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Dutch customers involved in aeronautical and topographic mapping

continued to request declination information over the Netherlands after

the closure of the Dutch magnetic service so that from 1999 onward,

the team from DOU performs yearly repeat measurements at several

Dutch stations, including former Witteveen Observatory, for producing

the isogonal maps.

Future perspect ives

The Belgian observatories DOU and MAB will remain open for the fore-

seeable future—especially as there is demand from the socioeconomic

sector for magnetic products and services in the Benelux. There is a

search going on for a new site in Belgium with reduced noise, espe-

cially as space weather research and forecasts needs clean short period

signals.

There are no plans in the Netherlands to resume the operation of

Witteveen Observatory. The TNG Observatory is in need of a better

observation site and improved instrumentation; international collabora-

tion with the Indonesian Meteorological and Geophysical Agency is

attempting this now.

There are talks between the Democratic Republic of Congo and

Belgium to resume operation in Binza, whose magnetic pavilions are

reported to be in good condition. A new Belgian Antarctic base might

also host a magnetic observatory 200 km south of RBD as part of a

contribution to the IPY in 2007–2008.

Jean L. Rasson

Bibliography

Flick, J.A., and Stomp, N., 2002. Sciences de la Terre au Luxem-

bourg—Réminiscences. Luxembourg: Musée National d’Histoire

Naturelle et ECGS.

Schreutelkamp, F.H., 2001. Het aardmagnetische veld ontrafeld. Zenit,

28: 136–141, 186–190.

De Vuyst, A., 1962. La variation de la Déclinaison Magnétique en

Belgique de 1828 à 1960.5. Contributions de l’Institut Royal

Météorologique de Belgique, 68.

Cross-references

Bemmelen, Willem van (1868–1941)

Geomagnetism, History of

Observatories, INTERMAGNET

OBSERVATORIES IN CANADA

The origin of the Canadian Magnetic Observatory Network (CANMON)

can be traced backto the founding of the Toronto Magnetic Observatoryin

1839. Except for a few temporary magnetic observatories, such as those

established during the First International Polar Year (1882–1883), Tor-

onto (later Agincourt) was the only magnetic observatory operating in

Canada until 1916, when Meanook was established. The network grew

substantially during the years preceding and following the International

Geophysical Year (1957–1958) and now consists of 13 observatories,

operated by the Geological Survey of Canada, Natural Resources

Canada (GSC).

Distribution of observatories

The CANMON extends over 40



of magnetic latitude, from 54.3



to 86.4



N, and includes three zones of differing magnetic activity:

subauroral, auroral, and polar cap. The distribution of observatories

relative to the three zones is shown in Figure O12. All observatories,

including those that are no longer in operation, are listed in Table O2.

Inuvik should be in operation by 2007.

Although the stations shown in Figure O12 are the only true mag-

netic observatories in Canada, several other magnetic variometer net-

works have been established to measure the unusual magnetic

conditions that result from the presence of the polar cap and auroral

zone. These include the CANOPUS (now CARISMA) network, the

MACCS network, and the THEMIS network, as well as several other

minor networks and single stations. In all, more than 80 permanent or

semipermanent magnetometers are currently operating in Canada.

Instrumentation

All magnetic observatories in the CANMON except Alert are part of

INTERMAGNET and are operated to INTERMAGNET standards

(see Observatories, INTERMAGNET ). Each observatory is equipped

with CANMOS (Canadian Magnetic Observatory System), a modular

system whose various components are controlled by a desktop PC, which

also serves as the data-acquisition system. The system is equipped with

two magnetometers: a three-component ring-core fluxgate for recording

variations in the X (north), Y (east), and Z (vertical) components, and an

Overhauser magnetometer for recording total intensity. The sensor of

the three-component magnetometer is mounted on a novel tilt-compensat-

ing suspension (Trigg and Olson, 1990), and both sensor and electronics

are housed in a temperature-controlled enclosure to minimize drift. The

system transmits 1-min data via the GOES satellite to downlinks located

at Ottawa and Golden, Colorado. At some observatories, 1-s data are

transmitted in real time via the Internet. The system is also accessible

via telephone modem, allowing remote monitoring and diagnosis of any

problems.

Each observatory is also equipped with a declination-inclination

magnetometer (DIM), consisting of a steel-free theodolite equipped with

a single-axis fluxgate sensor used for weekly absolute observations.

Data availability

Both preliminary and definitive data are available, filtered over the fol-

lowing intervals: 1 s, 5 s, and 1 min. Definitive data undergo rigorous

quality control and are calibrated using information derived from the

DIM and Overhauser magnetometers. Preliminary data are checked for

major spikes only. Preliminary 1-min data are available within 24 min.

For those observatories that transmit data via the Internet, the delay

Figure O12 Distribution of Canadian observatories: currently

operating (large squares); closed (circles); planned (triangle).

726 OBSERVATORIES IN CANADA

is at most a few minutes. Minute data may be plotted and down-

loaded from either the GSC Geomagnetic Laboratory’ s Web site

(www.gsc.nrcan.gc.ca/geomag/) or from the INTERMAGNET site

(http://www.intermagnet.org).

One- and 5-s data that are transferred in real time are available

almost instantly from the geomagnetic laboratory site. They are also

available from the Canadian Geospace Monitoring Program data portal

(ssdp.ca). Definitive data are normally available about 3 months after

year’s end. They replace the preliminary data at all sampling intervals

on all the above-mentioned Web sites. In addition, 1-min definitive

data are available on the INTERMAGNET CD and from World Data

Center Web sites.

Innovation

Magnetic observatories must evolve and adapt to meet the needs of the

scientific community that they serve. In addition to this scientific

imperative, development of the CANMON has been influenced by

the logistical, environmental, and economic challenges brought about

by the remoteness of many sites in this vast network. The presence

of the auroral zone and the proximity of the north magnetic pole also

present challenges in instrument design. These factors have provided

impetus for innovation. Many instrumental and procedural develop-

ments that are now considered common place were pioneered or

quickly adopted for use in CANMON. Most notable were the use of

the DIM as an absolute instrument, which began in the mid-1950s

(Serson and Hannaford, 1956; Loomer, 1961) and the development

of a semiautomated, digital network, which began in 1969 with the

installation of the AMOS system at St. John’s (Delaurier et al., 1974).

Lawrence R. Newitt and Richard Coles

Bibliography

Delaurier, J.M., Loomer, E.I., Jansen van Beek, J., and Nandi. A., 1974.

Editing and evaluating recorded geomagnetic components at Cana-

dian observatories. Publication of the Earth Physics Branch, 44(9):

235–242.

Loomer, E.I., 1961. Record of observations at Resolute Bay Magnetic

Observatory 1957–1956 with a summary of earlier observations.

Publications of the Dominion Observatory, 34(2): 25–131.

Serson, P.H., and Hannaford, W., 1956. A portable electrical magnet-

ometer. Canadian Journal of Technology, 34: 232–243.

Trigg, D.F., and Olson, D.G., 1990. Pendulously suspended magnet-

ometer sensors. Review of Scientific Instruments, 61: 2632–2636.

Cross-references

Observatories, Automation

Observatories, INTERMAGNET

Observatories, Overview

OBSERVATORIES IN CHINA

At present, there are 43 magnetic observatories in China’s mainland.

Forty of them are sponsored by the China Earthquake Administration

(CEA), formally China Seismological Bureau (CSB) and State Seis-

mological Bureau (SSB). Three others are sponsored by the Institute

of Geology and Geophysics, Chinese Academy of Sciences

(IGGCAS), formally the Institute of Geophysics, Chinese Academy

of Sciences (IGCAS). Among the 40 sponsored by the CEA, 3 new

ones are under construction and are expected to operate in 2007. All

of the CEA observatories will be equipped with at least two sets of

triaxial fluxgate magnetometers, one fluxgate theodolite, and one pro-

ton precession magnetometer in 2007. For the most important observa-

tories, an additional fluxgate theodolite and continuous recording of

total field by the Overhauser effect magnetometer will also be

deployed.

History

There were four major periods for the development of the magnetic

observatories in China’s mainland.

Table O2 Canadian magnetic observatories

Name IAGA code Geographic Geomagnetic First year Status

Alert ALE 82.497 297.647 86.89 23.2 1961 Operating

Mould Bay MBC 76.315 240.638 79.90 275.2 1962 Closed, 1995

Resolute Bay RES 74.690 265.105 82.90 302.9 1952 Operating

Cambridge Bay CBB 69.123 254.969 76.53 303.0 1972 Operating

Baker Lake BLC 64.318 263.988 73.17 322.1 1951 Operating

Iqaluit IQA 63.753 291.482 73.99 5.2 1994 Operating

Yellowknife YKC 62.820 245.518 69.25 299.0 1975 Operating

Fort Churchill FCC 58.759 265.912 67.94 328.4 1957 Operating

Poste-de-la-Baleine

(Great Whale River)

PBQ GWC 55.277 282.255 65.46 351.8 1967 Operating, will close

2007 (relocated, 1985)

Sanikiluaq SNK 56.536 280.769 67.23 350.6 2006 Replaces PBQ

Meanook MEA 54.616 246.653 61.57 306.2 1916 Operating

Brandon BRD 49.875 260.025 58.60 324.2 2006 Operating

Glenlea GLN 49.645 262.880 58.66 327.6 1982 Variometer since 1997;

closed 2005

Whiteshell WHS 49.700 264.75 58.89 330.1 1976 Closed, 1980

Victoria VIC 48.420 236.580 54.04 297.6 1956 Operating

St. John’s STJ 47.595 307.323 57.15 24.0 1968 Operating

Ottawa OTT 45.403 284.448 55.64 355.3 1968 Operating

Agincourt (Toronto) AGN TOR 43.783 280.733 53.94 350.8 1839 Closed, 1968

(relocated 1899)

OBSERVATORIES IN CHINA 727

Before the International Geophysical Year (IGY)

1957–1958

The first magnetic observatory in China was constructed in Beijing in

1870 by Russia. It ceased working in 1882. There had been other six

magnetic observatories with different periods of operation but all of

them had ceased working before 1944. One exception was Sheshan

(SSH) Observatory which was constructed in 1874 by French mission-

aries and is still in operation now.

During the IGY

During the IGY, construction of seven magnetic observatories includ-

ing Beijing (BJI), Changchun (CNH), Wuhan (WHN), Guangzhou

(GZH), Lanzhou (LZH), Lhasa (LSA) and Urumqi (WMQ) observa-

tories was initiated. Together with SSH, these eight observatories

became the backbone of the Chinese magnetic network.

From 1966 to 1979

The 1966 Xingtai Earthquakes triggered the beginning of the Chinese

research on earthquake prediction. Various observation methods were

utilized including magnetic observation. More than 200 magnetic

stations were set up around the country in the following years.

These stations were sponsored by different organizations and/or insti-

tutions with a variety of observational procedures and quality controls.

After 1979

In 1979, all of the magnetic observatories and stations were put under

the administration of the SSB. An organization (now the Geomagnetic

Network of China) in the Institute of Geophysics, SSB (IGSSB, now

IGCEA) was responsible for the technical support and data manage-

ment of the magnetic network. The network was readjusted several

times taking into account the distribution and the observational envir-

onment of the stations. Half of the stations ceased working. Mean-

while, instrumentation at 29 of the stations was improved to make

them operate as observatories. Later on, three other observatories were

set up in Mohe (1989), Beijing Mingtomb (BMT, 1993), and Sanya

(1995) by the IGCAS (now the IGGCAS).

Activities

All of the existing observatories have been producing yearbooks,

K-indices, and catalogs of magnetic storms. The Geomagnetic Net-

work of China is in charge of the quality control and dissemination

of the data from the CEA observatories. These magnetic observations

have been widely used in research work and applications related to

geomagnetic field.

The relatively short distances among the observatories have had

advantages. For example, the detection of errors in data by using

the method of interobservatory comparison is justifiable if the

observatories are close together. It also helps the scientists in research

work on earthquake prediction and regional characteristics of the

magnetic field.

Data from more than 15 observatories have been archived in the World

Data Center system. Some of the observatories have been participating in

international projects such as the Sino-American, Sino-Japanese, and

Sino-French projects. Three observatories have participated in INTER-

MAGNET (see Observatories, INTERMAGNET). With the improve-

ment of the instrumentation at the observatories, it is believed that there

will be more INTERMAGNET magnetic observatories from China’s

mainland in the near future.

Dongmei Yang

Cross-reference

Observatories, INTERMAGNET

OBSERVATORIES IN EAST AND

CENTRAL EUROPE

The first systematic magnetic observations in Central and Eastern Eur-

ope were made in Prague in 1839 by Karl Kreil (1798–1862), who

was assistant director, and from 1845 director of the Prague Observatory

and professor of astronomy at the Prague University. Measurements of

declination started in 1830. Kreil constructed and improved magnetic

instruments (using, among others, Gauss’s method of measuring the

horizontal component) and organized a rational system of magnetic

observations. From 1843 he also carried out a magnetic survey of the

Austrian Empire. In 1851, he was appointed the first Director of

the Central Institute of Meteorology and Geomagnetism (ZAMG) in

Vienna. The geomagnetic observatory started operating there in 1852.

The first Hungarian magnetic observatory was founded in Buda in

1871, but had to be closed in 1889 due to increased industrial activity,

which rendered the measurements unreliable. The magnetic observa-

tions continued in O’Gyalla under the auspices of the Royal Hungarian

Meteorological Institute. The geomagnetic observatory at O’Gyalla was

officially opened in 1900. The observatory was a witness of the turbu-

lent political development in Central Europe. Whereas many observa-

tories had to change their locations due to industrial noise, O’Gyalla,

having kept its original location, changed its name twice (Stará Ďala

in 1924 and Hurbanovo in 1948) and the country it belonged to five

times. In spite of this, Hurbanovo (IAGA code HRB) is the oldest oper-

ating observatory in Central and Eastern Europe.

Another geomagnetic observatory was established in 1880 in Pola

(Istria Peninsula) under the auspices of the Hydrographical Institute

of the Austro-Hungarian Imperial and Royal Navy. The data were also

used for reducing Italian magnetic surveys. The observatory was in

operation till 1925.

Before World War I, magnetic observations were made at several

other places, but the operation was usually short (less then 10 years)

and the only measured element was declination. Five observatories

were founded between the wars: Swider near Warsaw (1920, SWI)

and Hel (1932, HLP) in Poland, Wien Auhof (1929, WIA) in Austria,

Jassy (1931, JSS) in Romania, and Panagyurishte (1937, PAG) in Bul-

garia. On the other hand, Prague Observatory, located in the city center

since 1839, was finally closed down in 1926.

The present shape of the observatory network was formed after

World War II in a climate of increased interest in geosciences, also

supported by the International Geophysical Year in 1957/1958. Due

to the growth of industrial and urban magnetic noise more attention

was paid to the choice of the sites. Of course, it was not easy to foresee

future development. As regards the older observatories, only Hel,

Hurbanovo, and Panagyurishte were able to keep their original sites.

The Vienna Observatory was moved in 1955 from Auhof to Wien

Kobenzl (WIK). As this location is also not perfect, transfer to a qui-

eter place is being considered. The Prague Observatory was replaced

in 1946 by Pruhonice near Prague (PRU) but rapid expansion of the

city and construction of DC-powered railways resulted in a deteriora-

tion of this location. The observatory was moved to Budkov (BDV)

in south Bohemia, to a sparsely populated area, in 1967. Two observa-

tories were built in Hungary. The Tihany (THY) Observatory was

founded in 1953 in a protected area on the northern shore of Lake

Balaton. The tourism boom brought more traffic to this area than

had been expected; nevertheless, the conditions are still satisfactory.

Another observatory was built in 1956–1957 in Nagycenk (NCK) near

Sopron. Although the primary aim of the observatory was for the study

of the Earth’s electromagnetic field of external origin, it produces stan-

dard geomagnetic data. The Swider Observatory was affected by mag-

netic noise from Warsaw. An appropriate location was found in a rural

region about 50 km south of Warsaw in Belsk (BEL) and regular mea-

surements started in 1965. The Institute of Geophysics of the Polish

Academy of Sciences has also been operating the Hornsund (HRN)

Observatory in Spitsbergen since 1978. The Romanian observatory,

728 OBSERVATORIES IN EAST AND CENTRAL EUROPE

Surlari (SUA), was established in 1943 north-east of Bucharest. The

Serbian observatory, Grocka (GCK), began its operations during the

International Geophysical Year in 1957.

Most of the observatories joined the INTERMAGNET network

(number in brackets shows the first year the data were presented on

INTERMAGNET CD-ROM): Tihany (1991), Belsk (1993), Nagycenk

(1993), Budkov (1994), Hurbanovo (1997), Hel (1998), Surlari (1999),

and Hornsund (2002).

Two research groups are active in geomagnetic instrumentation

development. Torsion photoelectric magnetometers (TPM), based on

Bobrov-system quartz variometers, are being constructed in Belsk

since 1977. In these magnetometers, angular deflections of variometer

magnet mirrors are converted, by means of photoelectric convertors,

into electric voltage changes in a system with a strong negative feed-

back. The Tihany Observatory is developing digital data acquisition

systems DIMARS and DIMARK. They are designed for geomagnetic

observatories to measure and process output signals of vector fluxgate

and Overhauser proton precession magnetometers according to

INTERMAGNET standards.

Pavel Hejda

Cross-reference

INTERMAGNET

OBSERVATORIES IN GERMANY

Introduction

The tradition of geomagnetic observations in Germany spans back to the

16th century. In the early beginning, only the declination was observed

for the purposes of navigation and mining by means of compasses. Dur-

ing the 19th century the theories and measurement methods of geomag-

netic intensities were developed in Germany by Gauss and Weber.

The first “real” magnetic observatories in Germany were established

by Gauss and Weber in Göttingen; by Alexander von Humboldt in

Berlin and by Johann von Lamont in Munich. Today, three geomagnetic

observatories are in operation in Germany: Fürstenfeldbruck, Niemegk,

and Wingst, which all participate in the worldwide INTERMAGNET

network. Table O3 includes essential information about the German

observatories.

Development and international contribution

Early time series may be reconstructed from the notations by mining engi-

neers or sailors, inscriptions in old instruments and maps, and by correct-

ing these series with more recent observations. In Knothe (1987), the

declination observation series of Krakau (today Krakow, Poland), Danzig

(today Gdansk, Poland), Freiburg, Munich, and Clausthal are plotted

together with those of Prague, Böckstein (Austria), Copenhagen, Paris,

and London. Of course, these series are affected with large uncertainties,

but they are the earliest certificates of magnetic observations in Germany.

The German universal scientist Alexander von Humboldt (1769–

1859) initiated from 1827 onward with own studies and by inspiring

others progress in terrestrial magnetism in Germany. The mathematician

Carl Friedrich Gauss (1777–1855), inspired by Humboldt, formulated

the general theory of earth magnetism, developed the measurement

method for the absolute determination of the intensity and introduced

a system of physical units for geomagnetism from 1829 onward. When

Wilhelm Weber (1804–1891) came to Göttingen in 1831, one of the

most fruitful collaborations devoting to science started. In 1833, they

initiated the construction of a nonmagnetic house for geomagnetic

measurements in Göttingen. This magnetic observatory soon became

the center of the “Göttinger Magnetischer Verein (Göttingen Magnetic

Union).” This union, initiated by Humboldt, Gauss, and Weber, was

the first worldwide geomagnetic observatory network, which existed

from 1836 to 1841 and included 53 observatories, 18 of them non-Eur-

opean ones. All observatories took readings from their magnetometers

all 5 min during appointed days. The results were published by Gauss

and Weber together with scientific articles.

Observatories

Table O3 includes those German observatories that were in operation

for long periods, and which provided vector data of the Earth magnetic

induction vector. Table O4 shows general information about these

observatories, while Table O5 contains the used main instruments.

Summary and outlook

The German scientists Alexander von Humboldt, Carl Friedrich Gauss,

and Wilhelm Weber initiated the establishment of the first magnetic

observatories in Germany during the 1930s. They created the scientific

basements of the measurement and mathematical description of terres-

trial magnetism and developed suitable instruments. Further essential

theoretical and instrumental contributions were performed by Johann

von Lamont (1805–1879) and Adolf Schmidt (1860–1944). The

“Göttinger Magnetischer Verein” (Göttingen Magnetic Union), initiated

by Humboldt, Gauss, and Weber was the first worldwide geomagnetic

observatory network.

Due to several reasons, the first magnetic observatories (Göttingen,

Berlin, and Munich) that were established in the frame of the Göttingen

Magnetic Union do not exist any more. Industrial and urban distur-

bances forced the movement of the observatories from their first

locations within the cities to places far away from scientific centers.

Today there are three observatories Fürstenfeldbruck (successor of

Munich and Maisach), Niemegk (successor of Potsdam and Seddin),

and Wingst (successor of Wilhelmshaven). The time series span back

to 1840 (Munich-Maisach-Fürstenfeldbruck), 1890 (Potsdam-Seddin-

Niemegk), and 1878 (Wilhelmshaven-Wingst). The observatories coop-

erate closely, though they are sponsored by different scientific institutions:

Fürstenfeldbruck by the Institute of General and Applied Geophysics of

Munich University, Niemegk by the GeoForschungsZentrum Potsdam,

and Wingst by the GeoForschungsZentrum Potsdam and the Bundesamt

für Seeschifffahrt und Hydrographie Hamburg (German maritime

authority).

All three observatories produce minute, hourly, daily, monthly, and

annual mean values and K-indices. They send reported data in quasi

real-time and definitive data to INTERMAGNET. The observations

contribute in the frame of the worldwide network of magnetic observa-

tories to the database for scientific research of the Earth interior and the

Table O3 German geomagnetic observatories

Observatory Latitude (North) Longitude (East) Existence

Berlin 52.515



13.393



1836–1872

Fürstenfeldbruck 48.165



11.277



1939–

Göttingen 51.533



9.950



1833–1902

Maisach 48.200



11.260



1927–1937

Munich 48.147



11.608



1841–1925

Niemegk 52.070



12.680



1930–

Potsdam 52.380



13.060



1890–1931

Seddin 52.280



13.010



1907–1931

Wilhelmshaven 53.530



8.150



1878–1919,

1931–1936

Wingst 53.750



9.070



1938–

OBSERVATORIES IN GERMANY 729

Table O4 General information about German observatories

Observatory

station

Observation

period

Observers in charge Buildings Other observations

Berlin – 1836 –1872 J.F. Encke (1836–1865) and J.G. Galle

(1836–1872)

One nonmagnetic house at

the Berlin Astronomical

Observatory

–

Fürstenfeldbruck Munich, Maisach Operated continuously since

1937

F. Burmeister (1937–1957), K. Wienert

(1957–1978), M. Beblo (1978–2003),

and J. Matzka (2003–)

Five nonmagnetic, five

others

Seismological,

telluric currents,

and air electricity

Göttingen – 1833–1902 C.F. Gauss (1833–1855), W. Weber

(1833–1867), E. Schering (1867–1897),

and E. Wiechert (1897–1902)

One nonmagnetic house at

the Göttingen

Astronomical

Observatory

Seismological

Maisach Munich 1927–1937 F. Burmeister (1927–1937) One nonmagnetic hut and

use of brewery basement

Seismological,

telluric currents,

and air electricity

Munich – 1836–1925; observing gaps

of several years

J. v. Lamont (1836–1879), C. Feldkirchner

(1879–1886), F. Schwarz (1898–1902),

J.B. Messerschmitt (1902–1912),

F. Bidlingmaier (1912–1914),

Lutz (1914–1919), and F. Burmeister

(1919–1925)

Three nonmagnetic houses

at the Munich

Astronomical

Observatory

Seismological,

telluric currents,

and air electricity

Adolf Schmidt

Observatory

Niemegk

Potsdam, Seddin Operated continuously since

1930, with a short break of

nine months 1945/1946

A. Nippoldt (1930–1936), R. Bock (1936–1939),

G. Fanselau (1939–1968), H. Schmidt

(1969–1979), K. Lengning (1980–1982),

A. Best (1983–1998), and H.-J. Linthe (1999–)

Seven nonmagnetic houses

and 10 others

Telluric currents

Potsdam – 1890–1931 M. Eschenhagen (1890–1901), A. Schmidt

(1901–1927), and A. Nippoldt (1927–1931)

Two nonmagnetic houses –

Seddin Potsdam 1907–1931 A. Schmidt (1901 –1927) and A. Nippoldt

(1927–1931)

Two nonmagnetic houses,

one other

–

Wilhelmshaven – 1878– 1919;

1931–1936

C. Börgen (1878–1909), F. Bidlingmaier

(1909–1912), and P. Meier (1931–1936)

One nonmagnetic house Meteorological and

hydrographical

observations

Wingst Wilhelmshaven 1938– O. Meyer (1938–1954), D. Voppel (1954–1974),

G. Schulz (1974–2004), and H.-J. Linthe

(2004–)

730 OBSERVATORIES IN GERMANY

solar terrestrial relations. The Adolf Schmidt Observatory, Niemegk

is further responsible for the repeat station measurements and the

construction of magnetic maps of Germany. Niemegk Observatory

further carries out the Kp service for the International Service of Geo-

magnetic Indices of the IAGA. Niemegk and Wingst are Kp stations.

Hans-Joachim Linthe

Bibliography

Knothe, C., 1987. Secular variations of the magnetic declination in

middle Europe during the last 500 years, derived mostly from mine

surveying. In Proceedings of the IAGA-Symposium Space-Time-

Structure of the Geomagnetic Field. HHI-Report No. 21 (1987),

Berlin, pp. 90–98.

Neunhöfer, H., Börngen, M., Junge, A., and Schweitzer, J., (eds), 1997.

Zur Geschichte der Geophysik in Deutschland Jubiläumsschrift

Deutsche Geophysikalische Gesellschaft 1922–1997, Hamburg:

Deutsche Geophysikalische Gesellschaft.

Schroeder, W., and Wiederkehr, K.-H., 2002. Geomagnetic research

in the 19th century. Acta Geodaetica, Geophysica et Hungarica,

37(4): 445–466.

OBSERVATORIES IN INDIA

Magnetic observatories have been running in India for more than 180

years. Three of the oldest observatories, namely Madras Observatory

(1822–1881), Shimla Observatory (1841–1845), and Trivandrum

Observatory (1841–1871) participated in the international collabora-

tion venture involving simultaneous magnetic measurements at 50

observatories all over the globe organized by the Göttingen Magnetic

Table O5 Instruments used in the German observatories

Observatory Absolute instruments Variometers

Berlin Magnetometer for intensity determination by Meyerstein,

Göttingen; inclinometer by Gambey; declinometer by

Baumann

–

Fürstenfeldbruck Magnetic theodolite (D, H) and oscillation box (H) and

earth inductor by Schulze, Potsdam; proton vector

magnetometer after Nelson (F, H, Z; 1964; Wienert);

DI-flux theodolite Zeiss 010B/Bartington MAG010H

(D, I; 1992); Overhauser proton magnetometer GSM19

(F; 1996)

Two sets of variometers with photographic recording

(H, D, Z) by Schulze, Potsdam, and Edelmann, Munich;

three-component fluxgate variometers by FGE and

MAGSON (H, D, Z; 1996)

Göttingen Declinometer (D), and magnetometer for intensity (H)

after Gauß by Meyerstein, Göttingen; inclinometers (I)

by Robinson (1840) and Meyerstein (1847); earth

inductor (I) after Weber by Meyerstein (1868)

–

Maisach Two magnetic theodolites (D, H) by Bamberg, Berlin and

Tesdorpf, Stuttgart; earth inductors by Schulze, Potsdam

and Edelmann, Munich

One set of variometers with photographic recording

(H, D, Z) by Edelmann

Munich Meyerstein (Göttingen), declinometer (D), and intensity

instrument (H); magnetic theodolite (D, H, Z; 1841) by

Lamont; magnetic theodolite (D, H) and inclinometer (I)

by Bamberg, Berlin (1899); earth inductor (I) by

Edelmann, Munich (1908)

Magnetograph (1847) by Lamont

Adolf Schmidt

observatory

Niemegk

Magnetic theodolites by Wanschaff, Berlin and after

A. Schmidt (D and H); oscillation box by Schulze,

Potsdam (H); earth inductor by Schulze, Potsdam (I);

self-made proton magnetometers (H. Schmidt, 1968);

DI-flux theodolite Zeiss 010B/Bartington MAG01H

(D, I; 1996)

Four sets of classical variometers (H, D, Z) by Schulze,

Potsdam and Mating and Wiesenberg, Potsdam;

three-component fluxgate variometers FGE and

MAGSON (H, D, Z; 1996)

Potsdam Magnetic theodolite by Edelmann, Munich (D, H);

inclinometer by Bamberg, Berlin and earth inductor by

L. Weber (I); magnetic theodolite by Wanschaff

(D, H; 1893); earth inductor by Schulze, Potsdam

(I; 1901); oscillation box (H) and theodolite after

A. Schmidt (D, H; 1923)

One set of variometers (H, D, Z) by Carpentier, Paris, with

photographic recording equipment by Wanschaff, Berlin

(main system); one set of variometers (H, D, Z) by

Wild-Edelmann, Munich with visual reading (auxiliary

system)

Seddin – One set of variometers (X, Y, Z) by Schulze, Potsdam

Wilhelmshaven Declinometer after Neumayer by Bamberg, Berlin (D);

magnetic survey theodolite by Lamont, Munich (H);

earth inductor after Weber and inclinometer

by Dover (I)

One set of variometers (H, D, Z), visually readable, by

Lamont, Munich; one set of variometers (H, D, Z) with

photographic recording of Kew type by Adie, London

Wingst Magnetic theodolite (D, H), oscillation box (H), earth

inductor (I) by Schulze, Potsdam; proton vector

magnetometer after Voppel (F, H, Z; 1969); DI-flux

theodolite Zeiss 010B/Bartington MAG01H (D, I;

1992) and Overhauser proton magnetometer GSM19

(F; 1992)

One set of variometers with photographic recording by

Schulze, Potsdam (H, D, Z); 2 three-component

fluxgate variometers FGE (H, D, Z; 1993)

OBSERVATORIES IN INDIA 731

Union 1836–1841. The Colaba Observatory (Geographic latitude



N; longitude 72



E) was started in 1823 by the East

India Company. Initially it was undertaking mainly meteorological

observations to support the function of the Bombay Harbor. The first

regular magnetic field observations from Colaba were started in the

year 1841. In view of the proposed introduction of electric trams run-

ning on direct current in Bombay city in the year 1900, the then Direc-

tor Dr. Nanabhai A.F. Moos could envisage its deleterious effect on the

accuracy of magnetic measurements at Colaba Observatory. He made

enormous efforts to choose an alternate site at Alibag (Geographic lati-

tude 18



N; longitude 72



E), free from possible electro-

magnetic noises and in proximity to Colaba. The location of Alibag

Observatory is at about 30 km south-south east of Bombay facing

the Arabian Sea. The two historic nonmagnetic buildings, built com-

pletely with nonmagnetic Porbunder sandstone, brass, or copper fit-

tings at Alibag, are still in good condition. Alibag Magnetic

Observatory became operational from April 1904. These records over-

lapped with the Colaba records for a period of two years (1904–1906)

and subsequently recordings at Colaba were stopped. Thus at present,

Colaba-Alibag magnetic observatory data form a long series of more

than 160 years.

At present there are 13 permanent magnetic observatories in

India (Figure O13), and the Indian Institute of Geomagnetism (IIG),

Mumbai, operates nine of these. The Alibag Magnetic Observatory

joined the INTERMAGNET in 1993 when a Narod Ring Core Flux-

gate magnetometer from USGS was installed there. Recently, analog

variation magnetometers have been supplemented with digital fluxgate

magnetometers manufactured by Dannish Meteorological Institute

(DMI) at Tirunelveli, Pondicherry, Nagpur, Vishakhapatnam, and

Jaipur observatories operated by IIG. Modern absolute instruments,

such as declination inclination magnetometer (DIM), have been

installed at most of the observatories, to record and maintain the stability

in the baseline, which is a crucial parameter in computing the final abso-

lute values from variation data. A brief description of the magnetic

observatories currently operational is given below. Also included is a

map showing the locations of the magnetic observatories in India.

Alibag Magnetic Observatory: ABG (Operated by IIG, Mumbai),

Geographic (18.63



N, 72.87



E), Geomagnetic (at 2000.0 10.03



145.97



E).

This is the prime magnetic observatory of India. It was established

in April 1904 as a successor to Colaba Magnetic Observatory,

Bombay. The absolute instruments are vector proton precession

magnetometer (VPPM), quartz horizontal magnetometer (QHM), zero

balance magnetometer (BMZ), Kew No. 7 Magnetometer, and a DIM.

The variometers used are Kew magnetometer, Askania magnetometer,

La Cour variometer, and Izmiran II variometer.

Ettaiyapuram Magnetic Observatory: ETT (Operated by National

Geophysical Research Institute, NGRI, Hyderabad), Geographic

(9.00



N, 78.00



E), Geomagnetic (0.04



S, 149.99



E).

The Ettaiyapuram Magnetic Observatory was established in October

1979. The setup includes VPPM, QHM, BMZ, DIM, and a La Cour

variometer.

Gulmarg Magnetic Observatory: GUL (Operated by IIG, Mumbai),

Geographic (34.25



N, 74.41



E), Geomagnetic (25.56



N, 149.35



E).

Gulmarg Magnetic Observatory started functioning in September

1977. It has QHM, VPPM, DIM, and an Izmiran II variometer.

Hyderabad Magnetic Observatory: HYB (Operated by NGRI,

Hyderabad), Geographic (17.42



N, 78.55



E), Geomagnetic (8.29



151.29



E).

Hyderabad Magnetic Observatory was established in December 1964.

The setup has VPPM, QHM, BMZ, DIM, and a La Cour variometer.

Jaipur Magnetic Observatory: JAI (Operated by IIG, Mumbai),

Geographic (26.91



N, 75.80



E), Geomagnetic (17.98



N, 149.64



E).

The Jaipur Observatory was initially established in the year 1975 in

the Malvia Regional Engineering College Campus. The observatory

operations were discontinued from the year 1988. This observatory

was restarted in September 2002. The absolute instruments are VPPM,

QHM, BMZ, and DIM. The variation instrument is an Izmiran IV

variometer.

Kodaikanal Magnetic Observatory: KOD (Indian Institute of Astro-

physics, IIA, Bangalore), Geographic (10.23



N, 77.47



E), Geomag-

netic (1.23



N, 149.58



E).

Kodaikanal Magnetic Observatory was started in January 1949. The

setup includes Kew Magnetometer No. 3, galvanometer, Earth induc-

tor, La Cour variometer, and Watson’s variometer.

Nagpur Magnetic Observatory: NGP (Operated by IIG, Mumbai),

Geographic (21.15



N, 79.08



E), Geomagnetic (11.96



N, 152.14



E).

Nagpur Magnetic Observatory was commissioned in June 1991.

The setup has VPPM, DIM, and an Izmiran II variometer.

Pondicherry Magnetic Observatory: PON (Operated by IIG,

Mumbai), Geographic (11.92



N, 79.92



E), Geomagnetic (2.70



152.13



E).

Pondicherry Magnetic Observatory was established in January 1993

as a replacement for the Annamalainagar Observatory, Geographic

(11.40



N, 79.68



E), which operated from 1957 to 1993. Its location

is on the edge of the equatorial electrojet belt, which is a region under

the influence of ionospheric current systems associated with the dip

equator. The absolute instruments are DIM, PPM, VPPM, QHM, and

BMZ. The variometer is an Izmiran II variometer.

Sabhawala Magnetic Observatory: SAB (Operated by Survey of

India, SOI, Dehra Dun), Geographic (30.33



N, 77.80



E), Geomag-

netic (21.21



N, 151.86



E).

Sabhawala Magnetic Observatory was commissioned in January

1964. The setup includes QHM, BMZ, La Cour variometer, and Aska-

nia variometer.

Silchar Magnetic Observatory: SIL (Operated by IIG, Mumbai),

Geographic (24.93



N, 92.82



E), Geomagnetic (14.83



N, 165.38



E).

Silchar Magnetic Observatory was commissioned in November

1998. The setup has instruments DIM, PPM, VPPM, QHM, and

Izmiran II variometer.

Figure O13 Map showing the locations of permanent magnetic

observatories in India.

732 OBSERVATORIES IN INDIA

Shillong Magnetic Observatory: SHL (Operated by IIG, New Pan-

vel), Geographic (25.56



N, 91.88



E), Geomagnetic (15.69



164.72



E).

Shillong Magnetic Observatory started functioning from the middle

of the year 1975. It operates QHM, BMZ, VPPM, DIM, and Izmiran II

variometer.

Tirunelveli Magnetic Observatory: TIR (Operated by IIG, Mumbai),

Geographic (8.42



N, 77.48



E), Geomagnetic (0.57



S, 149.42



E).

The Tirunelveli Observatory started in March 1996 as successor

to IIGs Trivandrum Magnetic Observatory (Geographic: 8.48



76.95



E), which was in operation from 1957 to 1999. The absolute

instruments are DIM, PPM, BMZ, and QHM. The variation instrument

is an Izmiran II variometer.

Vishakhapatnam Magnetic Observatory: VSK (Operated by IIG,

Mumbai), Geographic (17.68



N, 83.32



E), Geomagnetic (8.17



155.89



E).

Vishakhapatnam Magnetic Observatory started functioning from

July 1994. The setup includes DIM, VPPM, QHM, and Izmiran II

variometer.

The observatory network in India is ideal for studying equatorial,

low- and midlatitude geomagnetic phenomena and space weather. The

Indian magnetic data is published by IIG. It is planned to preserve the

entire Colaba-Alibag unique data series by scanning and digitizing the

old magnetograms. In addition, IIG is operating World Data Center for

Geomagnetism, Mumbai. For more details, one can visit the Web site

of the Indian Institute of Geomagnetism, Mumbai, at iigs.iigm.res.in.

Gurbax S. Lakhina and S. Alex

Cross-references

Observatories, Instrumentation

Observatories, INTERMAGNET

OBSERVATORIES IN ITALY

Monitoring the Earth’s magnetic field is carried out by geomagnetic

observatories all over the world. In Italy, the first observatory was

founded in 1880, when Pietro Tacchini, the director of the Central

Meteorological Institute (Ufficio Centrale di Meteorologia), launched

an initiative to study the distribution of the Earth’s magnetic field over

the Italian territory. Prior to this, an initial attempt had been made by

Father Francesco Denza (1834–1894). In 1881, Tacchini proposed to

build an observatory in Rome, envisaging a nonmagnetic facility on

the Palatino hill. However this effort was hampered by administrative

difficulties. At the end of the 19th century, electromagnetic noise, gen-

erated mainly by the development of electrified transportation, affected

Rome as well as other Italian cities. Meanwhile the International Com-

mission for Terrestrial Magnetism was urging the Italian scientific

community to establish a magnetic observatory in southern regions

to facilitate the southern extension of the European network. The geo-

physical observatories in Catanzaro and in Messina, both located in

Southern Italy, were then proposed. However the strong earthquake

of 1905 in Sicily, which had dramatic consequences in Messina, scup-

pered plans to establish the magnetic observatory in the area.

In the meantime, repeat station measurements have been conducted

by Luigi Palazzo in several locations of the Italian territory. These sur-

veys indicated that satisfactory data reduction was achievable using the

magnetic data of the observatory of Pola, operating since 1881 in the

Istria Peninsula (Latitude 44.87



N, Longitude 13.85



S). At that time,

Istria belonged to the Austro-Hungarian Empire. When World War I

ended, Istria became part of Italy. Unfortunately, due to the electromag-

netic disturbances caused again by the city tramways, geomagnetic

recordings of the vertical component of the field were suspended. With

a further increase of the noise, in 1923, Pola was closed.

It was then in 1932 that a section of the Italian Navy, the Istituto

Idrografico della Marina, initiated regular absolute geomagnetic

measurements at Castellaccio (near Genova, Latitude 44.83



N, Long-

itude 8.93



E) along with variational recording using Pola Observa-

tory’s equipment. Castellaccio Observatory operated regularly and

published annual bulletins until 1962.

In the early fifties, the National Geophysical Institute (Istituto

Nazionale di Geofisica—ING) undertook the task to identify a suitable

location, from a geological and an environmental standpoint, for a

national geomagnetic observatory. Accurate surveys conducted in the

area of Preturo (Latitude 42.38



N, Longitude 13.32



E) near the city

of L’Aquila in central Italy, indicated an appropriate site. Funding

was secured in 1958 from Franco Molina. Preturo had been working

for two years as a variometer station. In 1960, absolute measurements

started to be carried out on a regular basis allowing the calculation of

the absolute values of the Earth’s magnetic field. This observatory is

known internationally as L’Aquila.

Although in different epochs, the three geomagnetic observatories

(Pola, Castellaccio, and L’Aquila) operated regularly during the last

century for a number of years, allowing the secular variation of declina-

tion and the horizontal component in Italy to be determined since 1881.

Another magnetic observatory was then installed by ING in the

north of the country, at Castello Tesino (Latitude 46.05



N, Longitude

11.65



E), and fitted with automatic recording equipment. Qualified

personnel perform absolute measurements regularly on a monthly

basis, guaranteeing the quality of the data.

Both L’Aquila and Castello Tesino are currently operating and

recording field values every minute, with regular transmission of data

to the data center at Rome.

Under the auspices of the Italian National Antarctic Research Pro-

gram, ING built and currently operate the Antarctic Italian Geomag-

netic Observatory Terra Nova Bay (Latitude 74.69



S, Longitude

164.12



E) located on the coast of the Ross Sea.

Massimo Chiappini

OBSERVATORIES IN JAPAN AND ASIA

Magnetic observations in Japan

Modern geomagnetic observation in Japan began on March 15, 1883,

in Tokyo, as an initiative of the Japanese government to join the First

Polar Year. In conjunction, a geomagnetic survey over all Japanese

islands was conducted. A well-equipped observatory in Tokyo was

started in 1897 by the meteorological agency and continued until

1917. Unfortunately, most of the records were burnt during the 1923

Tokyo earthquake. Because of the magnetic noise due to the construc-

tion of a DC train system in Tokyo, the observatory was moved. A

standard magnetic observatory in Kakioka, near Tokyo, was estab-

lished in 1913 and the observations are continuing.

There are currently four agencies conducting geomagnetic observa-

tions in Japan.

1. The Meteorological Agency of Japan operates three magnetic

observatories: Kakioka, Kanoya, and Memambetsu. These observa-

tories provide continuous geomagnetic data with precise absolute

measurements. There is also one unmanned observatory, Chichijima.

The main purpose of these observatories is for monitoring volcanic

or earthquake activity, and it also deploys instruments for tempor-

ary observations during a volcanic eruption or strong earthquake.

The observations are also used for research.

OBSERVATORIES IN ITALY 733

2. The Geographical Survey Institute of Japan operates three magnetic

observatories—Kanozan, Mizusawa, and Esashi—and 11 unmanned

continuous observation sites. They conduct magnetic surveys at

repeat stations and publish magnetic charts of Japan every 10 years.

3. The Hydrographic and Oceanographic Department has one obser-

vatory, Hatizyo. They conduct surveys by ship or airplane over

the sea around the Islands of Japan and publish magnetic charts.

4. The National Institute of Advanced Industrial Science and Technol-

ogy (AIST) conducts Aeromagnetic surveys over the Islands of

Japan and publishes magnetic charts.

Other than the observatories mentioned above (see also Table O6),

there are many observation sites for scientific research that mainly

belong to universities or national institutions.

Magnetic observation in Indonesia

The Indonesian Meteorological and Geophysical Agency (IMGA) oper-

ates three geomagnetic observatories: Tondano Geomagnetic Observa-

tory (TND, 1.29



N, 124.95



E) in North Sulawesi, Tangerang

Geomagnetic Observatory (TNG, 6.17



S, 106.63



E) in Jakarta, and

Tuntungan Geomagnetic Observatory (TTG, 3.50



N, 98.56



E) in North

Sumatra. Geomagnetic observations at TNG started in 1964 using the

Ruska type photographic paper variograph. TNG was upgraded in 1991

with a digital magnetometers. The observatory Tondano began collecting

observations in 1991 with digital fluxgate and proton magnetometer.

Tuntungan Geomagnetic Observatory (TTG) has been observing the

geomagnetic field since 1980 using a La Cour photographic variograph,

and after 2003 was equipped with a digital magnetometer.

Magnetic observation in Vietnam

The Hanoi Institute of Geophysics, National Centre for Natural

Science and Technology of Vietnam currently operates four geomag-

netic observatories in Vietnam; Cha Pa (CPA, 22.35



N, 103.83



E),

Bac Lieu (BCL, 9.3



N, 105.7



E), Phu Thuy (PHU, 21.03



105.95



E), and Dalat (DLT, 11.93



N, 108.48



E). The magnetic obser-

vations at CPA and PHU began in 1957 and 1978, respectively.

Toshihiko Iyemori and Heather McCreadie

OBSERVATORIES IN LATIN AMERICA

Introduction

During colonial times, geomagnetism in Latin American countries

was restricted to declination measurements for cartography and the

definition of borders. A large survey was performed by E. Halley

(see Halley, Edmond), in 1700, when he prepared his famous magnetic

chart of the South Atlantic. Following Halley’s work, it was not until

1880 that a large field survey was made by the Dutch scientist Van

Rickjervosel in the Brazilian coastal area. That observational work

was completed by the publication of the first Brazilian magnetic chart.

Since no observatories existed in those times, they could be considered

as the prehistoric phase of geomagnetism in Latin America.

Birth and development of Latin American magnetic

observatories

In the first half of the 20th century a considerable effort was made by

the Carnegie Institution of Washington (see Carnegie Institution of

Washington, Department of Terrestrial Magnetism ) to improve geo-

magnetism in South America. Observatories were installed in Peru

and Argentina. Local efforts were made in various countries, some-

times with the assistance of the Inter-American Geodetic Survey, and

the Pan-American Institute of Geography and History (PAIGH), to

install other observatories. This phase lasted from 1920 to 1960. Chir-

ipa Magnetic Observatory in Costa Rica is a good example of that

international cooperation.

Lately, Peruvian observatories (Huancayo and Ancón) received con-

siderable assistance from Japanese institutions, mainly from Tokyo

University. In spite of a good beginning, some observatories lost their

initial quality and some of them were closed.

In 1980, PAIGH started a campaign, under the leadership of the

National Observatory of Brazil, to reorganize and modernize all obser-

vatories in Latin America. The most important part of that campaign

was a series of Latin American geomagnetic schools, where the train-

ing of technicians and also the installation of modern instruments

transformed old and unproductive observatories into operational ones.

Important international contribution for these improvements came

from the action of two IAGA Divisions, Division V (observatories,

instruments, surveys, and analyses) and the Interdivision Commission

on Developing Countries (see IAGA, International Association of

Geomagnetism and Aeronomy). From this, the observatories of Trelew

(Argentina) and La Habana (Cuba) received new magnetic instru-

ments, such as digital fluxgate variometers and modern absolute

instruments.

Besides the observatories mentioned above and others included in

the summary below, there are some variation stations (where no abso-

lute observations are carried out) that are operated for specific research

projects. Among these stations the most important are located in

Brazil, Peru, and Mexico.

It is interesting to note the importance and responsibility of Latin

American magnetic observatories, not only for the great latitude range

of the group (66



), but also for the occurrence of two important geo-

magnetic phenomena in the region—the equatorial electrojet and the

South Atlantic magnetic anomaly.

Table O7 gives data for all observatories in the region.

Table O6 Listing of magnetic observatories, operated by the government in Japan

Station name Abb. GGLAT. Long. GMLAT. Elev. Year HD I

Chichijima CBI 27.10 142.18 18.47 155 2003 32609 –03.61 37.28

Esashi ESA 39.24 141.35 30.46 396 2000 29095 –06.87 52.68

Hatizyo HTY 33.08 139.82 24.21 220 2002 31346 –07.47 46.11

Kakioka KAK 36.23 140.19 27.37 36 2003 29980 –07.06 49.72

Kanoya KNY 31.42 130.88 21.89 107 2003 32776 –05.93 44.97

Kanozan KNZ 35.26 139.96 26.39 342 2000 30366 –06.71 48.57

Memambetsu MMB 43.91 144.19 35.35 42 2003 26182 –08.78 58.09

Mizusawa MIZ 39.11 141.21 30.32 130 2000 28646 –07.89 52.92

734 OBSERVATORIES IN LATIN AMERICA

Acknowledgments

Data for each observatory were furnished by the local person in charge

of the station.

Luiz Muniz Barreto

Cross-references

Carnegie Institution of Washington, Department of Terrestrial Magnetism

Halley, Edmond (1656–1742)

IAGA, International Association of Geomagnetism and Aeronomy

OBSERVATORIES IN NEW ZEALAND AND THE

SOUTH PACIFIC

New Zealand has been involved in five magnetic observatories over

the last century. In New Zealand, there has been a succession of three

observatories located at Christ-church, Amberley, and Eyrewell. The

others are Apia in Samoa and Scott Base in the Antarctic. The Apia

and Scott Base observatories were only intended to operate for limited

durations, but Apia has continued for over 100 years and Scott Base

for nearly 50 years.

Observatories in New Zealand

Dr. Schmidt had drawn attention to the desirability of an observatory

in New Zealand (Schmidt, 1897), and referring to this paper in his

presidential address to Section A of the Australasian Association

for the Advancement of Science Mr. Barrachi said, “The establish-

ment of a magnetic observatory in New Zealand seems to be a duty

that colony owes to the Scientific world” (Farr, 1916). With support

from the commander in chief of the Australian Naval Station and the

Shipmasters’ Association of New Zealand, government funding was

obtained for both a survey and the establishment of a magnetic

observatory.

The observatory was established in the botanic gardens in Christ-

church using Adie magnetographs and a new Kew magnetometer

(No. 1C.Sc.I.Co) and Dip Circle No.147 for absolute observations.

Christ-church soon became magnetically disturbed by electric trams.

A substation, which eventually replaced Christ-church, was established

at Amberley 43 km north of Christ-church using Eschenhagen magne-

tographs. In 1957, a set of La Cour variometers was installed at

Amberley (J. A. Lawrie, personal communication).

In the mid-1960s a DC power line was erected to transfer power

between the North and South Islands of New Zealand. It consists of

two independent conductors (mounted on the same pylons where the

line is over land) with a common earth return. Each conductor was

capable of independently carrying up to 1200 A (since increased to

1800 A). At the observatory, this produced a vertical field proportional

to the net current flowing in the two conductors. The maximum distur-

bance was 12 nT. A sensor was installed under the lines to measure the

net current flowing in the conductors and provide a correction field

around the Z variometer.

In 1977, development around Amberley forced the establishment of

a new observatory at Eyrewell, about 22 km northwest of the original

Christ-church Observatory. Digital recording instruments designed and

built by the author were introduced in June 1990 allowing it to become

an INTERMAGNET observatory in 1994.

Table O7 Summary

Country

Name of

observatory

Geographic coordinates

Year of installation Actual status

Latitude Longitude

Argentina Trelew 48.2



S 204.7



W 1957 Normal operation

INTERMAGNET station

Pilar 31.7



S 296.1



W 1905 Irregular operation

Orcadas 60.7



S 315.6



W 1904 Irregular operation

La Quiaca 22.1



S 294.4



W 1920 Closed in 1975

Las Acacias 35.0



S 302.3



W 1957 Not operating since 1997

Bolivia Patacamaya 17.3



S 292.1



W 1983 Irregular operation

Brazil Vassouras 22.4



S 316.4



W 1915 Classical instruments up to 1993

INTERMAGNET (1993)

Original

Instruments operation as backup

Tatuoca 1.2



S 311.5



W 1957(IGY) Classical instruments normal

operation

Brasilia 14.9



S 312.1



W Programmed for Dic.2005

São Martinho 29.4



S 53.8



W Programmed for Dic.2005

Chile Isla De Pascoa –– 1957(IGY) Closed

Costa Rica Chiripa 10.4



N 275.1



W 1984 Classical. Normal operation

Colombia Fuquene 5.5



N 280.3



W 1954 Classical. Normal operation

Cuba La Habana 23.1



N 277.5



W 1964 INTERMAGNET IN 1997

Mexico Teoloyucan 19.7



N 260.8



W 1914 moved in 1978 Classical instruments

INTERMAGNET 2002

Peru Huancayo 12.0



S 284.7



W 1922 by CIW Classical instruments

INTERMAGNET 2002

Ancon 11.7



S 282.9



W 1984 Digital variometer and modern

absolute instruments

Arequipa 16.4



S 288.5



W 1957 Classical instruments

Normal operation

OBSERVATORIES IN NEW ZEALAND AND THE SOUTH PACIFIC 735