Study of the level of total electron content disturbance in

the middle-latitudeand Arctic regions by GPS data

Natalia P. Perevalova (1), Ilya K. Edemskiy (1), Olga V. Timofeeva (1, 2), Darya D. Katashevtseva (1, 2), Anna S. Polyakova (1)

(1) Institute of Solar-Terrestrial Physics, SB RAS

(2) Irkutsk State University

Bolshie Koty, Russia

2

𝑰= ∫𝑺𝒃𝒐𝒕

𝑺𝒕𝒐𝒑

𝑵𝒆𝒅𝒔

𝑰= 𝟏𝟒𝟎 .𝟑𝟎𝟖

𝒇 𝟏𝟐 𝒇 𝟐

𝟐

𝒇 𝟏𝟐− 𝒇 𝟐

𝟐 [ (𝑳𝟏𝝀𝟏−𝑳𝟐𝝀𝟐)+𝒄𝒐𝒏𝒔𝒕𝟏 ,𝟐+𝝈 𝑳]

Baikal School, 2015

Total Electron Content (TEC)

The total electron content I is the electron density Ne integrated along a

beam:

TEC calculation using the phase measurements at two GNSS frequencies:

where и is the phase path increments of the radio signals; and , phase measurements by GNSS-receiver made at frequencies of f1 and f2 ; ambiguity of phase measurements; , phase measurement error.

TEC

3Baikal School, 2015

WTEC index GPS/GLONASS station

exercises control of TEC variations in a radius of 500-1000 km;

The time observation of a GPS satellite at the station is about 2-6 hours.

WTEC is multi-day series of averaged TEC disturbance

[Berngardt O.I., Voeykov S.V., Ratovsky K.G. Using a single GPS/GLONASS receiver for estimating the level of ionospheric disturbance // XXXI URSI General Assembly and Scientific Symposium. Beijing, China. August 16-23, 2014: abstracts. 2014. GP2.31]

4Baikal School, 2015

Measurement data for 2013

Filtration period:01-10 minutes -

medium-scale ionospheric disturbances;

01-40 minutes- large-scale ionospheric

disturbances.

Planetary geomagnetic indexes:AE characterizes high latitudes; Dst, low latitudes;

Kp, middle latitudes.

5Baikal School, 2015

WTEC variations in March and June, 2013

The WTEC variations for two ranges of periods (01-10 min, 01-40 min) at the NRIL, MOND, ORDA stations and behavior of Dst, Kp, AE geomagnetic indexes. The vertical dashed lines indicate sudden storm commencements.

middle-latitudes

high-latitudes

geomagnetic indexes

6

ST at 100 km ST at 300 km

Baikal School, 2015

Diurnal-seasonal WTEC variations

The Diurnal-seasonal WTEC variations for ranges of periods of 01-10 min (a, c) and 01-40 min (b, d) at the NRIL (a, b) and MOND (c, d) stations. The black lines mark sunrise time at 100 km (solid) and 300 km (dashed). ST stands for the solar terminator.

7

CONCLUSIONS

Baikal School, 2015

In Arctic region The minimal level of disturbance intensity does not depend on the

season. WTEC behavior correlates well with the variations in AE index and

does less with the behavior of the Dst index. WTEC variations caused by the solar terminator are absent.

In middle latitudes Diurnal WTEC variations are particularly pronounced over the year

and have also some seasonal features. The minimal level of disturbance intensity in summer is higher than in

winter. The solar terminator generates intense large-scale ionospheric

disturbances, but does not cause medium-scale ones.

8

THANK YOU FOR YOUR ATTENTION!

Baikal School, 2015

9

Day of the year (UT)

Tim

e (t

)

nT

Baikal School, 2015

10

Solar terminator

2013, days

LT

, h

Baikal School, 2015

11

Solar terminator

Baikal School, 2015

12

Все спутники GPS передают сигналы на двух одинаковых частотах:

f1 = 1575.42МГц и f2= 1227.60МГц

Спутники ГЛОНАСС передают сигналы на разных частотах в двух диапазонах.

Первый диапазон имеет центральную частоту f01= 1602 МГц, частота передачи спутников определяется по формуле:

f1k=f01+k*Δf1 где Δf1=0,5625 МГц, k - номер частотного канала (k=-7,-6,-5,...0,...).

Второй диапазон имеет центральную частоту f02 = 1246 МГц,частота передачи спутников определяется по формуле:

f2k=f02+k* Δf2 где Δf2=0.4375 МГц, k - номер частотного канала (k=-7,-6,-5,...0,...).

Радиосигналы в ГНСС GPS и ГЛОНАСС

Baikal School, 2015