TY - JOUR

T1 - Detecting atmospheric normal modes with periods less than 6 h by barometric observations

AU - Швед, Густав Моисеевич

AU - Ермоленко, Светлана Игоревна

AU - Jacobi, Christoph

N1 - Funding Information: Barometer data have been kindly provided by through the GGP project. S.I. Ermolenko acknowledges support by the German-Russian Interdisciplinary Science Center (G-RISC) funded by the German Federal Foreign Office via the German Academic Exchange Service (DAAD) . We would like to thank an anonymous reviewer for comments which significantly helped to improve the manuscript.

PY - 2018/4

Y1 - 2018/4

N2 - The theory of atmospheric normal modes (ANMs) predicts the existence of relatively short-period gravity-inertia ANMs. Simultaneous observations of surface air-pressure variations by barometers at distant stations of the Global Geodynamics Project network during an interval of 6 months were used to detect individual gravity-inertia ANMs with periods of ∼2–5 h. Evidence was found for five ANMs with a lifetime of ∼10 days. The data of the stations, which are close in both latitude and longitude, were utilized for deriving the phases of the detected ANMs. The phases revealed wave propagation to the west and increase of zonal wavenumbers with frequency. As all the detected gravity-inertia ANMs are westward propagating, they are suggested to be generated due to the breakdown of migrating solar tides and/or large-scale Rossby waves. The existence of an ANM background will complicate the detection of the translational motions of the Earth's inner core.

AB - The theory of atmospheric normal modes (ANMs) predicts the existence of relatively short-period gravity-inertia ANMs. Simultaneous observations of surface air-pressure variations by barometers at distant stations of the Global Geodynamics Project network during an interval of 6 months were used to detect individual gravity-inertia ANMs with periods of ∼2–5 h. Evidence was found for five ANMs with a lifetime of ∼10 days. The data of the stations, which are close in both latitude and longitude, were utilized for deriving the phases of the detected ANMs. The phases revealed wave propagation to the west and increase of zonal wavenumbers with frequency. As all the detected gravity-inertia ANMs are westward propagating, they are suggested to be generated due to the breakdown of migrating solar tides and/or large-scale Rossby waves. The existence of an ANM background will complicate the detection of the translational motions of the Earth's inner core.

KW - Atmospheric normal modes

KW - Earth's inner core oscillations

KW - Global atmospheric waves

UR - http://www.scopus.com/inward/record.url?scp=85040013937&partnerID=8YFLogxK

U2 - 10.1016/j.jastp.2017.12.007

DO - 10.1016/j.jastp.2017.12.007

M3 - Article

VL - 169

SP - 1

EP - 5

JO - Journal of Atmospheric and Solar-Terrestrial Physics

JF - Journal of Atmospheric and Solar-Terrestrial Physics

SN - 1364-6826

ER -