Institute for Scientific Research
Boston College

 

 

 

 

 

 

AMBER is the name of a small town located in the northwestern part of Ethiopia

AMBER (African Meridian B-field Education and Research)

NASA IHY Funded Project

PIs: Endawoke Yizengaw (PI) and Mark Moldwin (Co-I) from Boston College and University of Michigan, respectively

It was quickly recognized that the observation of ionospheric processes over Africa represented the best opportunity for new science. In order to have a complete global understanding of equatorial ionosphere motions, deployment of ground-base magnetometers in Africa is essential. One focus of IHY is the deployment of networks of small instruments, including the development of research infrastructure in developing nations through the United Nations Basic Space Science (UNBSS) Small Instrument Array. Today over 30 new instrument installations are either installed or in process, and the NASA funded AMBER (African Meridian B-Field Education and Research) magnetometer array is one of those deployed in Africa. The AMBER magnetometer array is comprised of four magnetometers. All of them are already stationed in Adigrat in Ethiopia, Algiers in Algeria, Yaounde in Cameroon, and Tsumeb in Namibia. Recently, in colaboration with SAMBA project, the fifth magnetometer, known as AMBER-SAMBA magnetometer, has been deployed in Abuja, Nigeria. The Figure shows the location of AMBER and SAMBA-AMBER magnetometer network. The specific location of each stations is shown in Table 1. While polar-cap to equatorial coverage exist in the American meridian with the deployment of McMAC array linking the expanded Canadian CARISMA (formerly CANOPUS) and the SAMBA arrays, in Europe the coverage essentially ends with SEGMA in Italy. AMBER array is now connecting the European magnetometer array to low latitudes by filling the largest land-based gap in global magnetometer coverage in Africa, as is shown in the Figure. AMBER stations in Algiers, Abuja, Yaounde, and in Tsumeb will be used for connecting IMAGE-SAMNET-SEGMA array to low and dip-equator latitudes, and link up with South African Intermagnet and Antarctic magnetometers in the southern hemisphere so that we can have complete meridian observation in the region.

In addition to filling the largest land-based gap in global magnetometer coverage, the AMBER array will address two fundamental areas of space physics:

(1) the processes governing electrodynamics of the equatorial ionosphere as a function of latitude (or L-shell), local time, longitude, magnetic activity, and season, and

(2) ULF pulsation strength and its connection with equatorial electrojet strength at low/mid-latitude regions.

In coordination with GPS receivers in Africa, AMBER magnetometer array will provide a great opportunity to understand the electrodynamics that governs equatorial ionosphere motions. By combining AMBER in Adigrat (~6.0 N magnetic) and INTERMAGNET in Addis Ababa (~0.13 N magnetic) for east-african sector and AMBER in Yaounde (~5.9 S magnetic) and SAMBA-AMBER in Abuja (~0.55 S magnetic) for west-African sector, the strength of equatorial electrojet (EEJ) and thus vertical ExB drift is routinely estimated using a well known pair of magnetometers drift estimation technique. Therefore, while the magnetometers routinely observe the F region plasma drift mechanism (ExB drift), the GPS stations will monitor the structure of plasma at low/mid-latitudes in the African sectors. Such combined observations provide enormous opportunity to understand the unique equatorial ionospheric structures in the African sector that have been often detected by satellite observations.

In addition to new scientific discoveries and advancing the space science research into Africa by establishing scientific collaborations between scientists in the developing and developed nations, the AMBER project also contributes to the effort in developing the basic science of heliophysics through cross disciplinary studies of universal process. This includes the creation of sustainable research/training infrastructure within the African universities. This will then create opportunities for undergraduate students to enhance their inspiration to space science and perform research activities in the future within their own countries. Data from AMBER magnetometer array will be directly accessible to space weather forecasters and the space science community at large.

Recently, AMBER project received funding to expand (red dots in Figure shown here) the existing magnetometer network in order to address the following fundamental science problems: (1) What are the processes governing the formation of the four-cell pattern in a day-to-day basis as function of local time, magnetic activity, season, and solar cycle? (2) what are the longitudinal differences in the generation and development of plasma bubbles/irregularities, especially at the longitudes where the four-cell pattern peaks are located; Is there any connection between the dayside drifts and the formation of the bubbles/irregularities, primarily at the nodes of the four-cell pattern where the drifts are believed to be stronger?

Table 1: The geographic and geomagnetic locations of AMBER magnetometer stations

 

Name of Stations

Code

Geog. Lat

Geog. Long

Mag. Lat

Mag. Long

L-Shell

Status

Medea, Algeria

ALGR

36.85 N

2.93 E

27.98 N

77.67 E

1.3

Deployed

Adigrat, Ethiopia

ETHI

14.28 N

39.46 E

5.90 N

111.06 E

1.0

Deployed

Yaounde, Cameroon

CMRN

3.87 N

11.52 E

5.30 S

83.12 E

1.0

Deployed

Tsumeb, Namibia

NMBA

19.20 S

17.58 E

29.91 S

86.16 E

1.3

Deployed

Abuja, Nigeria

ABJA

10.5 N

7.55 E

0.55 S

79.63 E

1.0

Deployed

Belem, Brazil

BELM

1.45 S

48.50 W

1.05 S

25.34 E

1.0

Deployed

Petrolina, Brazil

PETA

9.4 S

40.5 W

6.95 S

30.21 E

1.0

Deployed

Conakry, Guinea

CNKY

10.5 N

13.71 W

0.46 S

60.37 E

1.0

Deployed

Abidjan, Cote d'Ivoire

ABAN

4.60 N

6.64 W

6.0 S

65.82 E

1.0

Deployed

Bangkok, Thailand

SONG

14.1 N

100.6 E

6.2 N

172.17 E

1.0

Deployed

Puhket, Thailand

PUKT

7.89 N

98.40 E

0.63 S

169.95 E

1.0

Deployed

Manila, Philippines

MNLA

14.58 N

120.90 E

7.02 N

167.86 W

1.0

Deployed

Davao, Philippines

DAVO

7.06 N

125.60 E

0.96 S

163.27 W

1.0

Deployed

Christmas Island

CHIS

1.87 N

157.40 W

1.4 N

86.39 W

1.0

To be Deployed

Kwajalein

KWJL

9.19 N

167.46 E

5.12 N

122.22 W

1.0

To be Deployed