Abstract. A long-lived gravity wave (GW) in the atmospheric boundary layer (ABL) is analysed during a field experiment Anqing, China (30∘37′ N, 116∘58′ E). Persistent GWs with periods ranging from 10 to 30 min over h ABL within 2 km height are detected by coherent Doppler lidar 4 5 September 2018. The amplitudes of vertical wind due these approximately 0.15–0.2 m s−1. lifetimes longer than 20 cycles. There no apparent phase progression altitude. and zonal perturbations 90∘ out phase,...

Abstract. Long-lived metallic ions in the Earth's atmosphere (ionosphere) have been investigated for many decades. Although seasonal variation ionospheric “sporadic E” layers was first observed 1960s, mechanism driving remains a long-standing mystery. Here, we report study of irregularities using scintillation data from COSMIC satellites and identify large-scale horizontal transport long-lived ions, combining simulations Whole Atmosphere Community Climate Model with chemistry metals...

Abstract This study reports an extreme ionospheric plasma depletion event over the Eastern Pacific from postmidnight to early morning during superstorm's recovery phase on 21 November 2003 observed by DMSP F13, ROCSAT‐1, GRACE, and CHAMP satellites, two ground‐based GPS receivers. The its interhemispheric geomagnetic conjugate effect occurred between ∼40°S 40°N latitudes. suggests a possible extremely long‐range flux tube connection with apex altitude exceeding 6,000 km equator. Notably, for...

Neutral metal layers such as Na, Mg, and Fe occur in the Earth's mesosphere lower thermosphere (80-120 km) region due to ablation of cosmic dust. These provide important tracers chemical dynamical processes within this region. Nonmigrating diurnal tides are persistent global oscillations atmospheric fields (e.g., wind, temperature, density) with a period 24 hours nonsynchronous propagation sun. A complex combination tidal forcing, chemistry, photochemistry drives cycle these meteoric atoms....

Abstract. The existing distribution of meteor radars located from high- to low-latitude regions provides a favorable temporal and spatial coverage for investigating the climatology global mesopause density. In this study, we report relative density estimated using multiyear observations nine radars, namely, Davis Station (68.6∘ S, 77.9∘ E), Svalbard (78.3∘ N, 16∘ E) Tromsø (69.6∘ 19.2∘ at high latitudes; Mohe (53.5∘ 122.3∘ Beijing (40.3∘ 116.2∘ Mengcheng (33.4∘ 116.6∘ Wuhan (30.5∘ 114.6∘ in...

Abstract Multiyear high‐frequency gravity wave (GW) momentum fluxes and variances in the mesosphere lower thermosphere region are revealed using four meteor radars along 120°E longitude at Northern Hemisphere midlatitudes for first time, which located Mohe (53.5°N, 122.3°E), Beijing (40.3°N, 116.2°E), Mengcheng (33.3°N, 116.5°E), Wuhan (30.5°N, 114.2°E), respectively. The seasonal latitudinal variations of GW midlatitude discussed. directions monthly mean zonal mostly against background...

Abstract. The NCAR Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension (WACCM-X) v2.1 has been extended to include the neutral ion–molecule chemistry dynamics of three metals (Mg, Na, Fe), which are injected into upper mesosphere–lower by meteoric ablation. Here we focus on self-consistent electrodynamical transport metallic ions in both E F regions. model full ion significantly improves simulation global distribution seasonal variations Mg+, although peak...

Abstract In this study we analyze the lightning data obtained by World‐Wide Lightning Location Network (WWLLN) and hourly ionospheric observed ionosondes located at Sanya Beijing, to examine changes in electron density response underlying thunderstorms investigate possible connection between discharges enhancement of sporadic E ( s ) layer. We identify a statistically significant decrease altitude layer station, agreement with results found Chilton, UK. However, lightning‐associated...

Abstract We present the migrating tidal winds decomposed jointly from multiple meteor radars in four longitudinal sectors situated equatorial mesosphere and lower thermosphere. The are located Cariri, Brazil (7.4°S, 36.5°W), Kototabang, Indonesia (0.2°S, 100.3°E), Ascension Island, United Kingdom (7.9° S, 14.4° W), Darwin, Australia (12.3°S, 130.8°E). Harmonic analysis was used to obtain amplitudes phases for diurnal semidiurnal solar tides between 82 98 km altitude during period 2005–2008....

Abstract Atomic sodium (Na) is one of the major meteoric species existing as layers atoms in mesosphere/lower thermosphere (MLT) at altitudes 80–105 km and atomic ions higher altitudes. As boundary between neutral atmosphere ionosphere, MLT region particular interest because it influenced by mesoscale convective weather thunderstorms from below exposed to solar photons above. There has been great on atmosphere‐ionosphere coupling, numerous studies have reported connection ionosphere....

Abstract Atmospheric gravity waves (GWs) significantly influence global circulation. Deep convection, particularly that associated with typhoons, is believed to be an important source of waves. Stratospheric induced by Typhoon Mindulle (2004) were detected the Infrared Sounder (AIRS). Semicircular GWs horizontal wavelengths 100–400 km found over Taiwan through inspection AIRS radiances at 4.3 μm. Characteristics stratospheric generated investigated using Weather Research and Forecasting...

A meteor radar chain located along the 120°E meridian in Northern Hemisphere from low to middle latitudes provides long-term horizontal wind observations of mesosphere and lower thermosphere (MLT) region. In this study, we report a seasonal variation its latitudinal feature mean MLT region observed by 6 radars at Mohe (53.5°N, 122.3°E), Beijing (40.3°N, 116.2°E), Mengcheng (33.4°N, 116.5°E), Wuhan (30.6°N, 114.4°E), Kunming (25.6°N, 108.3°E) Fuke (19.5°N, 109.1°E) stations. addition, compare...

Abstract Background Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia worldwide; confers an increased risk of adverse outcomes and once diagnosed patients will require lifelong-treatment. Population-based studies AF incidence are needed to inform health-service planning. However, few reports refer a standard population estimates in high income countries vary by over 12-fold. Purpose We aimed assess trends crude standardised atrial sex, age, socioeconomic status region...

In this study, we present nearly 9 years of the quasi16-day wave (Q16DW) in mesosphere and lower thermosphere (MLT) wind at middle latitudes based on long-term observations between April 2014 December 2022 by Mengcheng (33.4°N, 116.5°E) meteor radar. There are two maxima Q16DW amplitude winter early spring (near equinox) a minimum during summer. The Q16DWs relatively weak meridional winds with no obvious seasonal variations. On average, phase zonal is larger than components mean difference...

This study presents the observations of midlatitude plasma irregularities over Eastern Asia during a moderate magnetic storm on 16 July 2003. Multi-instrumental observations, including ground-based ionosondes, GNSS networks, and CHAMP ROCSAT-1 satellites, were utilized to investigate occurrence characteristics irregularities. The strong spread F (SSF) mainly occurred in midnight–morning sector as observed by ionosondes Japan this storm. SSF was related depletions, which is also recorded...

Abstract. Ionospheric sporadic E layers (Es) are intense plasma irregularities between 80 and 130 km in altitude generally unpredictable. Reconstructing the morphology of is not only essential for understanding nature ionospheric many other atmospheric coupling systems, but also useful solving a broad range demands reliable radio communication sectors reliant on ionosphere-dependent decision-making. Despite efforts empirical theoretical models, predictive algorithm with both high accuracy...

Abstract National Center for Atmospheric Research Whole Atmosphere Community Climate Model (WACCM) with quasi‐uniform grid of ∼25‐km horizontal resolution can resolve gravity waves (GWs) scales down to ∼250 km. In this study, the scale interactions between GWs resolved by WACCM and those smaller scales, its potential impact on waves, dependence wave characteristics spatial are examined. The Weather Forecasting (WRF) simulations five different resolutions (25, 20, 15, 10, 4 km) performed,...

Abstract To investigate the response of meteoric metal layers in mesosphere and lower thermosphere regions to 27‐day solar rotational cycle, a long‐term simulation Whole Atmosphere Community Climate Model with chemistry three metals (Na, K, Fe) was analyzed. The correlation between variability forcing during different phases 11‐year cycle reveals that is much stronger maximum. altitude‐dependent sensitivity spectral irradiance demonstrates there significant increase increasing altitude....

Abstract Background Mepiquat chloride (MC) application and plant population density (PPD) increasing are required for modern cotton production. However, their interactive effects on leaf physiology carbohydrate metabolism remain obscure. This study aimed to examine whether how MC PPD affect the morpho-physiological characteristics, thus final yield. of three levels (D1: 2.25 plants·m −2 , D2: 4.5 D3: 6.75 ) dosage two (MC0: 0 g·ha MC1: 82.5 were combined create six treatments. The dynamics...

Abstract We present a multi-instrument experiment to study the effects of tropospheric thunderstorms on mesopause region and lower ionosphere. Sodium (Na) lidar ionospheric observations by two digital sounders are used variation in neutral metal atoms metallic ions above thunderstorms. An enhanced sporadic E layer with downward tidal phase is observed followed subsequent intensification Na number density an increase 600 cm −3 mesosphere. In addition, chemistry ion-molecule considered model...

The atmospheric temperatures and densities in the mesosphere lower thermosphere (MLT) region are essential for studying dynamics climate middle upper atmosphere. In this study, more than 9 years of mesopause relative estimated by using ambipolar diffusion coefficient measurements observed Mengcheng meteor radar (33.4°N, 116.5°E) presented. intercomparison between Thermosphere Ionosphere Mesosphere Energetics Dynamics/Sounding Atmosphere Broadband Emission Radiometry (TIMED/SABER) EOS...