Impacts of CME‐induced geomagnetic storms on the midlatitude mesosphere and lower thermosphere observed by a sodium lidar and TIMED/GUVI

Yuan, Tao; Zhang, Yongliang; Cai, Xuguang; She, C. Y.; Paxton, L. J.

doi:10.1002/2015gl064860

Cited by 36 publications

(39 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Li et al (2018) carried out first-principles simulations of MLT neutral temperature (T n ) response at middle latitudes using the Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIMEGCM). They showed that the simulated MLT temperature changes similar to the lidar observations (40°N, 105°W) at this place (Yuan et al, 2015). They found through diagnostic analysis of model outputs that storm-time MLT T n changes at middle latitudes are produced mainly by adiabatic heating/cooling and heat advection associated with vertical wind changes.…”

Section: Introductionmentioning

confidence: 61%

A Modeling Study of the Responses of Mesosphere and Lower Thermosphere Winds to Geomagnetic Storms at Middle Latitudes

Wang

et al. 2019

JGR Space Physics

View full text Add to dashboard Cite

Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIMEGCM) simulations are diagnostically analyzed to investigate the causes of mesosphere and lower thermosphere (MLT) wind changes at middle latitudes during the 17 April 2002 storm. In the early phase of the storm, middle‐latitude upper thermospheric wind changes are greater and occur earlier than MLT wind changes. The horizontal wind changes cause downward vertical wind changes, which are transmitted to the MLT region. Adiabatic heating and heat advection associated with downward vertical winds cause MLT temperature increases. The pressure gradient produced by these temperature changes and the Coriolis force then drive strong equatorward meridional wind changes at night, which expand toward lower latitudes. Momentum advection is minor. As the storm evolves, the enhanced MLT temperatures produce upward vertical winds. These upward winds then lead to a decreased temperature, which alters the MLT horizontal wind pattern and causes poleward wind disturbances at higher latitudes.

show abstract

Section: Introductionmentioning

confidence: 61%

A Modeling Study of the Responses of Mesosphere and Lower Thermosphere Winds to Geomagnetic Storms at Middle Latitudes

Wang

et al. 2019

JGR Space Physics

View full text Add to dashboard Cite

show abstract

“…This may explain the lidar observed stronger solar flux index of the LM, which is mostly controlled by the adiabatic circulation, compared to the HM. Indeed, the evidence of MLT temperature response to solar activity is recently revealed by the lidar observations (Yuan et al, ) and the associated studies by the recent Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIME‐GCM) simulation during a coronal mass ejection event (Li et al, ). These studies have demonstrated the change of adiabatic flow in middle latitude MLT during these extreme solar events, which induced the corresponding temperature enhancement in the upper atmosphere.…”

Section: Discussionmentioning

confidence: 96%

The Long‐Term Trends of Nocturnal Mesopause Temperature and Altitude Revealed by Na Lidar Observations Between 1990 and 2018 at Midlatitude

et al. 2019

Self Cite

View full text Add to dashboard Cite

The mesopause, a boundary between mesosphere and thermosphere with the coldest atmospheric temperature, is formed mainly by the combining effects of radiative cooling of CO2, and the vertical adiabatic flow in the upper atmosphere. A continuous multidecade (1990‐2018) nocturnal temperature data base of an advanced Na lidar, obtained at Fort Collins, CO (41°N, 105°W), and at Logan, UT (42°N, 112°W), provides an unprecedented opportunity to study the long‐term variations of this important atmospheric boundary. In this study, we categorize the lidar‐observed mesopause into two categories: the “high mesopause” (HM) above 97 km during nonsummer months, mainly formed through the radiative cooling, and the “low mesopause” (LM) below 92 km during nonwinter months, generated mostly by the adiabatic cooling. These lidar observations reveal a cooling trend of more than 2 K/decade in absolute mesopause temperature since 1990, along with a decreasing trend in mesopause height: The HM is moving downward at a speed of ~ 450 ± 90 m/decade, while the LM has a slower downward trend of ~ 130 ± 160 m/decade. However, since 2000, while the height trend (‐ 470 ± 160 m/decade for the HM and 150 ± 290 m/decade for the LM) is consistent, the temperature trend becomes statistically insignificant (‐ 0.2 ± 0.7 K/decade and ‐1 ± 0.9 K/decade for the HM and the LM, respectively). A long‐term study by Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension (WACCM‐X) also indicated the similar mesopause changes, mostly caused by stratosphere‐lower mesosphere cooling and contraction.

show abstract

“…They found that particle precipitation enhanced the temperature above 100 km but cannot modify the temperature below 100 km. More recently, by analyzing the nighttime temperature measured by a sodium lidar at Fort Collins, Colorado (41°N), and then transferred to Logan, Uath (42°N), Yuan et al (2015) presented a significant warming above 95 km (as much as 55 K at 105 km) during the peaks of the four coronal mass ejection-induced geomagnetic storms.…”

Section: 1029/2018gl078039mentioning

confidence: 99%

Responses of Lower Thermospheric Temperature to the 2013 St. Patrick's Day Geomagnetic Storm

Xiao

Yue

Wang

et al. 2018

Geophysical Research Letters

View full text Add to dashboard Cite

The altitude‐ and latitude‐dependent responses of neutral temperature in the lower thermosphere to the 2013 St. Patrick's Day geomagnetic storm have been studied using neutral temperature measurements from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument onboard the TIMED satellite and the Solar Occultation For Ice Experiment (SOFIE) instrument onboard the AIM satellite. Both SABER and SOFIE observations revealed that both temperature increase (having peaks of ~15–25 K) and decrease (having peak of ~15 K), which were associated with the storm, occurred in the two hemispheres. The magnitudes of temperature variations changed with latitude, altitude, and the phase of the storm. The peaks of the temperature increase occurred 0.5–1.5 days later than the peak of the AE index, depending on latitude and height. Global circulation changes initiated due to heating and ion drag in the auroral region are likely responsible for the temperature increases or decreases in the lower thermosphere.

show abstract

Impacts of CME‐induced geomagnetic storms on the midlatitude mesosphere and lower thermosphere observed by a sodium lidar and TIMED/GUVI

Cited by 36 publications

References 27 publications

A Modeling Study of the Responses of Mesosphere and Lower Thermosphere Winds to Geomagnetic Storms at Middle Latitudes

A Modeling Study of the Responses of Mesosphere and Lower Thermosphere Winds to Geomagnetic Storms at Middle Latitudes

The Long‐Term Trends of Nocturnal Mesopause Temperature and Altitude Revealed by Na Lidar Observations Between 1990 and 2018 at Midlatitude

Responses of Lower Thermospheric Temperature to the 2013 St. Patrick's Day Geomagnetic Storm

Contact Info

Product

Resources

About