Influence of geomagnetic disturbances on mean winds and tides in the mesosphere/lower thermosphere at midlatitudes

Jacobi, Ch.; Lilienthal, Friederike; Korotyshkin, D.; Merzlyakov, E. G.; Stober, Gunter

doi:10.5194/ars-19-185-2021

Cited by 2 publications

(3 citation statements)

References 39 publications

(62 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our results reveal an impact of geomagnetic activity on mesosphere wind in summer (Figures 5 and 6), with higher geomagnetic activity weakening the winds at both middle and high latitudes, except for the eastward wind at high latitudes, which strengthens under disturbed conditions. The results at middle latitudes agree with Jacobi et al (2021), who found weaker wind at a higher geomagnetic activity at two mid-latitude stations Collm and Kazan during the summers of 2016-2020.…”

Section: Impact Of Geomagnetic Activity On Trendssupporting

confidence: 91%

“…The Ap index varies between 0 and 400 and is the product of a conversion of the daily average of the 3-hour-mean Kp index (Matzka et al, 2021). Following the study at middle latitudes by Jacobi et al (2021), we extend the work to 33 years below 82 km at middle latitudes, and to high latitudes with the complete 19-year time series and investigate the response to disturbed and undisturbed geomagnetic conditions during summer. We divided the days of the years with low geomagnetic activity, Ap ≤ 5, and high geomagnetic activity, Ap≥ 20 for middle latitudes and Ap≥ 15 for high latitudes.…”

Section: Discussionmentioning

confidence: 99%

“…Andenes is located at 67 • N. Renkwitz and Latteck (2017) showed the response of the MLT to the change in the Kp index at the location of the radar. In the case of middle latitudes, we use the limits already established by Jacobi et al (2021). The time period used for the summer mean is 2004-2022, except for the zonal vertical profile (below 82 km) and meridional (below 80 km) at middle latitudes, where the time period used is 1990-2022.…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Long-term studies of the summer wind in the mesosphere and lower thermosphere at middle and high latitudes

Jaen

Renkwitz

Liu

et al. 2023

Preprint

View full text Add to dashboard Cite

Abstract. Continuous wind measurements using partial reflection radars and specular meteor radars have been carried out for nearly two decades (2004–2022) at middle and high latitudes over Germany (∼54° N) and northern Norway (∼69° N), respectively. They provide crucial data for understanding the long-term behavior of winds in the mesosphere and lower thermosphere. Our investigation mainly focuses on the summer season, characterized by the absence of intense planetary wave activity and relatively stable stratospheric conditions. This work presents the long-term behavior, variability and trends of the maximum velocity of the summer eastward, westward and southward winds. In addition, the geomagnetic influence on the summer zonal and meridional wind is explored at middle and high latitudes. The results show that a westward summer maximum is located around 75 km with velocities of 35–54 m/s, while the eastward wind maximum is observed at ∼97 km with amplitudes of 25–40 m/s. A weaker southward wind peak is found around 86 km ranging from 9–16 m/s. The findings indicate significant trends at middle latitudes in the westward summer maxima with increasing winds over the past decades, while the southward winds show a decreasing trend. On the other hand, only the eastward wind in July has a decreasing trend at high latitudes. Evidence of oscillations around 2–3, 4 and 6 years modulate the maximum velocity of the summer winds. Particularly a periodicity between 10.2–11.3 years found in the westward component is more significant at middle latitudes than at high latitudes, possibly due to solar radiation. Furthermore, stronger geomagnetic activity at high latitudes causes an increase in eastward wind velocity, whereas the opposite effect is observed in zonal jets at middle latitudes. The meridional component appears disturbed during high geomagnetic activity, with a notable decrease in the northward wind strength below approximately 80~km at both latitudes.

show abstract

Section: Impact Of Geomagnetic Activity On Trendssupporting

confidence: 91%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Long-term studies of the summer wind in the mesosphere and lower thermosphere at middle and high latitudes

Jaen

Renkwitz

Liu

et al. 2023

Preprint

View full text Add to dashboard Cite

show abstract

Long-term studies of the summer wind in the mesosphere and lower thermosphere at middle and high latitudes over Europe

Jaen,

Renkwitz,

Liu

et al. 2023

Atmos. Chem. Phys.

View full text Add to dashboard Cite

Abstract. Continuous wind measurements using partial-reflection radars and specular meteor radars have been carried out for nearly 2 decades (2004–2022) at middle and high latitudes over Germany (∼ 54∘ N) and northern Norway (∼ 69∘ N), respectively. They provide crucial data for understanding the long-term behavior of winds in the mesosphere and lower thermosphere. Our investigation focuses on the summer season, characterized by the low energy contribution from tides and relatively stable stratospheric conditions. This work presents the long-term behavior, variability, and trends of the maximum velocity of the summer eastward, westward, and southward winds. In addition, the geomagnetic influence on the summer zonal and meridional wind is explored at middle and high latitudes. The results show a mesospheric westward summer maximum located around 75 km with velocities of 35–54 m s−1, while the lower-thermospheric eastward wind maximum is observed at ∼ 97 km with wind speeds of 25–40 m s−1. A weaker southward wind peak is found around 86 km, ranging from 9 to 16 m s−1. The findings indicate significant trends at middle latitudes in the westward summer maxima with increasing winds over the past decades, while the southward winds show a decreasing trend. On the other hand, only the eastward wind in July has a decreasing trend at high latitudes. Evidence of oscillations around 2–3, 4, and 6 years modulate the maximum velocity of the summer winds. In particular, a periodicity between 10.2 and 11.3 years found in the westward component is more significant at middle latitudes than at high latitudes, possibly due to solar radiation. Furthermore, stronger geomagnetic activity at high latitudes causes an increase in eastward wind velocity, whereas the opposite effect is observed in zonal jets at middle latitudes. The meridional component appears to be disturbed during high geomagnetic activity, with a notable decrease in the northward wind strength below approximately 80 km at both latitudes.

show abstract

Influence of geomagnetic disturbances on mean winds and tides in the mesosphere/lower thermosphere at midlatitudes

Cited by 2 publications

References 39 publications

Long-term studies of the summer wind in the mesosphere and lower thermosphere at middle and high latitudes

Long-term studies of the summer wind in the mesosphere and lower thermosphere at middle and high latitudes

Long-term studies of the summer wind in the mesosphere and lower thermosphere at middle and high latitudes over Europe

Contact Info

Product

Resources

About