Anomalous changes of temperature and ozone QBOs in 2015−2017 from radiosonde observation and MERRA-2 reanalysis

Abstract. Several works concerning the dynamical and thermal structures and inertial gravity wave activities in the troposphere and lower stratosphere (TLS) from the radiosonde observation have been reported before, but these works were concentrated on either equatorial or polar regions. In this paper, background atmosphere and gravity wave activities in the TLS over Wuhan (30° N, 114° E) (a medium latitudinal region) were statistically studied by using the data from radiosonde observations on a twice daily basis at 08:00 and 20:00 LT in the period between 2000 and 2002. The monthly-averaged temperature and horizontal winds exhibit the essential dynamic and thermal structures of the background atmosphere. For avoiding the extreme values of background winds and temperature in the height range of 11-18km, we studied gravity waves, respectively, in two separate height regions, one is from ground surface to 10km (lower part), and the other is within 18-25km (upper part). In total, 791 and 1165 quasi-monochromatic inertial gravity waves were extracted from our data set for the lower and upper parts, respectively. The gravity wave parameters (intrinsic frequencies, amplitudes, wavelengths, intrinsic phase velocities and wave energies) are calculated and statistically studied. The statistical results revealed that in the lower part, there were 49.4% of gravity waves propagating upward, and the percentage was 76.4% in the upper part. Moreover, the average wave amplitudes and energies are less than those at the lower latitudinal regions, which indicates that the gravity wave parameters have a latitudinal dependence. The correlated temporal evolution of the monthly-averaged wave energies in the lower and upper parts and a subsequent quantitative analysis strongly suggested that at the observation site, dynamical instability (strong wind shear) induced by the tropospheric jet is the main excitation source of inertial gravity waves in the TLS.

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An Observational and Model Characterization of Vertical Structure of Wind Fields over Eastern United States: A Case Study of Sterling, Virginia

Advances in Meteorology ◽

10.1155/2016/2020379 ◽

2016 ◽

Vol 2016 ◽

pp. 1-15

Author(s):

Sium Gebremariam ◽

Belay Demoz ◽

Churchill Okonkwo ◽

Ricardo K. Sakai

Keyword(s):

Wind Speed ◽

Vertical Distribution ◽

Interannual Variability ◽

Signal To Noise Ratio ◽

Coupled Model ◽

Cmip5 Models ◽

Eastern United States ◽

Wind Fields ◽

Reanalysis Dataset ◽

Radiosonde Observation

The performance of twenty GCMs that participated in the Coupled Model Intercomparison Phase 5 (CMIP5) is evaluated at Sterling, Virginia, by comparing model outputs with radiosonde observational dataset and reanalysis dataset. We evaluated CMIP5 models in their ability to simulate wind climatology, seasonal cycle, interannual variability, and trends at the pressure levels from 850 hPa to 30 hPa. We also addressed the question of the number of years required to detect statistically significant wind trends using radiosonde wind measurements. Our results show that CMIP5 models and reanalysis successfully reproduced the observed climatological annual mean zonal wind and wind speed vertical distribution. They also capture the observed seasonal zonal, meridional, and wind speed vertical distribution with stronger (weaker) wind during the winter (summer) season. However, there is some disagreement in the magnitude of vertical profiles among CMIP5 models, reanalysis, and radiosonde observation. Overall, the number of years to obtain statistically significant trend decreases with increasing pressure level except for upper troposphere. Although the vertical profile of interannual variability of CMIP5 models and reanalysis agree with the radiosonde observation, the wind trend is not statistically significant. This indicates that detection of trends on local scale is challenging because of small signal-to-noise ratio problems.

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Evaluation of the GOES-R ABI LAP Retrieval Algorithm Using the GOES-13 Sounder

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-13-00028.1 ◽

2014 ◽

Vol 31 (1) ◽

pp. 3-19 ◽

Cited By ~ 15

Author(s):

Yong-Keun Lee ◽

Zhenglong Li ◽

Jun Li ◽

Timothy J. Schmit

Keyword(s):

Microwave Radiometer ◽

Precipitable Water ◽

Retrieval Algorithm ◽

Earth Observing System ◽

Radiosonde Observation ◽

Global Positioning ◽

Atmospheric Radiation Measurement ◽

Atmospheric Profile ◽

Infrared Radiances ◽

Environmental Prediction

Abstract A physical retrieval algorithm has been developed for deriving the legacy atmospheric profile (LAP) product from infrared radiances of the Advanced Baseline Imager (ABI) on board the next-generation Geostationary Operational Environmental Satellite (GOES-R) series. In this study, the GOES-R ABI LAP retrieval algorithm is applied to the GOES-13 sounder radiance measurements (termed the GOES-13 LAP retrieval algorithm in this study) for its validation as well as for potential transition of the GOES-13 LAP retrieval algorithm for the operational processing of GOES sounder data. The GOES-13 LAP retrievals are compared with five different truth measurements: radiosonde observation (raob) and microwave radiometer–measured total precipitable water (TPW) at the Atmospheric Radiation Measurement Cloud and Radiation Testbed site, conventional raob, TPW measurements from the global positioning system–integrated precipitable water NOAA network, and TPW measurements from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E). The results show that with the GOES-R ABI LAP retrieval algorithm, the GOES-13 sounder provides better water vapor profiles than the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) forecast fields at the levels between 300 and 700 hPa. The root-mean-square error (RMSE) and standard deviation (STD) of the GOES-13 sounder TPW are consistently reduced from those of the GFS forecast no matter which measurements are used as the truth. These substantial improvements indicate that the GOES-R ABI LAP retrieval algorithm is well prepared to provide continuity of quality to some of the current GOES sounder products, and the algorithm can be transferred to process the current GOES sounder measurements for operational product generation.

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The Layered Structure of the Winter Atmospheric Boundary Layer in the Interior of Alaska

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-12-01.1 ◽

2013 ◽

Vol 52 (4) ◽

pp. 953-973 ◽

Cited By ~ 19

Author(s):

John A. Mayfield ◽

Gilberto J. Fochesatto

Keyword(s):

Boundary Layer ◽

Statistical Analysis ◽

Atmospheric Boundary Layer ◽

Layered Structure ◽

High Latitude ◽

Meteorological Conditions ◽

Formation Mechanisms ◽

Observation Data ◽

Interior Alaska ◽

Radiosonde Observation

AbstractThe high-latitude winter atmospheric boundary layer of interior Alaska continually exhibits a complex layered structure as a result of extreme meteorological conditions. In this paper the occurrence of elevated inversions (EI), surface-based inversions (SBI), and stratified layers in the sub-Arctic from January 2000 to December 2009 is reported. This statistical analysis is based on radiosonde observation data from the Fairbanks National Weather Service station complemented by Winter Boundary Layer Experiment observations in the period 2010–11. This study found that SBIs occurred 64% of the time. An SBI occurred in combination with one, two, three, or four simultaneous EIs 84.86%, 48.49%, 21.23%, and 7.99% of the time, respectively, in 2326 total cases. The calculated mean SBI height was 377 m; EIs occurred at 1231, 2125, 2720, and 3125 m, respectively. This analysis was able to discriminate between locally controlled inversion layers and synoptic-dependent inversions and to identify their formation mechanisms. It was found that, in the presence of an SBI layer, the first EI layer formed 35.8% of the time under anticyclonic conditions at a mean height of 1249 m and 22% of the time in warm-air-advection situations at a mean height of 1049 m. The remaining 23.4% resulted from combined synoptic situations, and 18.8% were unclassified.

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Study of GPS Radiosonde observation system in Goa

MAUSAM ◽

10.54302/mausam.v63i2.1424 ◽

2021 ◽

Vol 63 (2) ◽

pp. 291-298

Author(s):

S.M. METRI

Keyword(s):

Navigation System ◽

Air Pressure ◽

Wind Data ◽

Observation System ◽

The Past ◽

Radiosonde Observation ◽

Gps Radiosonde

Meteorological Radiosonde in the past used to apply navigation system to rout to determine the upper air pressure, temperature, humidity and the wind data through Radars. In this paper GPS Radiosonde test has been recently introduced in IMD is studied. The observations taken from M2K2 Radiosonde have been discussed. GPS Radiosonde obtains wind data as well.

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Long-Term Change in Characteristics of Cloud Vertical Structures Over Sumatra from Radiosonde Observations

JURNAL ILMU FISIKA | UNIVERSITAS ANDALAS ◽

10.25077/jif.13.1.41-53.2021 ◽

2021 ◽

Vol 13 (1) ◽

pp. 41-53

Author(s):

Lismalini Lismalini ◽

Marzuki Marzuki ◽

Mohammad Ali Shafii

Keyword(s):

Relative Humidity ◽

Vertical Structure ◽

Ground Level ◽

Occurrence Rate ◽

Cloud Base ◽

Term Change ◽

Radiosonde Observation ◽

The One ◽

Layer Cloud

Study on the vertical structure of cloud in Indonesia in terms of climate change is still very limited. We investigated the long-term change in characteristics of cloud vertical structures over Sumatra from three radiosonde observation stations in this work. The cloud base height (CBH), cloud top height (CT), and the number of cloud layers were retrieved using relative humidity (RH) profiles from radiosonde observation. The height of the cloud base is determined by taking the height of the layer with relative humidity (RH) value > 84% with at least a 3% jump in the RH from the ground level. Sumatra’s most frequently observed cloud layer is a one-layer cloud with an average occurrence rate of > 60%, which is slightly larger than the one-layer cloud globally. The percentage of appearance values at the Padang station, Pangkal Pinang, and Medan are 63.58%, 69.50% and 66.05%. The appearance of low-level clouds also dominates in Sumatra compared to other cloud types. CT and CBH increase with the number of years including all seasons. This is in line with the increase in temperature in Indonesia reported by previous researchers. On the other hand, the clouds’ thickness, especially for the cloud with one layer, varies from one location to another. The thickness of clouds decreases at Padang station and does not change at Pangkal Pinang and Medan stations.

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Initial Assessment of the COSMIC-2/FORMOSAT-7 Neutral Atmosphere Data Quality in NESDIS/STAR Using In Situ and Satellite Data

Remote Sensing ◽

10.3390/rs12244099 ◽

2020 ◽

Vol 12 (24) ◽

pp. 4099

Author(s):

Shu-Peng Ho ◽

Xinjia Zhou ◽

Xi Shao ◽

Bin Zhang ◽

Loknath Adhikari ◽

...

Keyword(s):

Water Vapor ◽

Data Quality ◽

Signal To Noise Ratio ◽

Initial Assessment ◽

Observation System ◽

Neutral Atmosphere ◽

Satellite Mission ◽

Radiosonde Observation ◽

Satellite Applications ◽

The Mean

A COSMIC-1/FORMOSAT-3 (Constellation Observing System for Meteorology, Ionosphere, and Climate-1 and Formosa Satellite Mission 3) follow-on mission, COSMIC-2/FORMOSAT-7, had been successfully launched into low-inclination orbits on 25 June 2019. COSMIC-2 has a significantly increased Signal-to-Noise ratio (SNR) compared to other Radio Occultation (RO) missions. This study summarized the initial assessment of COSMIC-2 data quality conducted by the NOAA (National Oceanic and Atmospheric Administration) Center for Satellite Applications and Research (STAR). We use validated data from other RO missions to quantify the stability of COSMIC-2. In addition, we use the Vaisala RS41 radiosonde observations to assess the accuracy and uncertainty of the COSMIC-2 neutral atmospheric profiles. RS41 is currently the most accurate radiosonde observation system. The COSMIC-2 SNR ranges from 200 v/v to about 2800 v/v. To see if the high SNR COSMIC-2 signals lead to better retrieval results, we separate the COSMIC-2–RS41 comparisons into different SNR groups (i.e., 0–500 v/v group, 500–1000 v/v group, 1000–1500 v/v group, 1500–2000 v/v group, and >2000 v/v group). In general, the COSMIC-2 data quality in terms of stability, precision, accuracy, and uncertainty of the accuracy is very compatible with those from COSMIC-1. Results show that the mean COSMIC-2–RS41 water vapor difference from surface to 5 km altitude for each SNR groups are equal to −1.34 g/kg (0–500 v/v), −1.17 g/kg (500–1000 v/v), −1.33 g/kg (1000–1500 v/v), −0.93 g/kg (1500–2000 v/v), and −1.52 g/kg (>2000 v/v). Except for the >2000 v/v group, the high SNR measurements from COSMIC-2 seem to improve the mean water vapor difference for the higher SNR group slightly (especially for the 1500–2000 v/v group) comparing with those from lower SNR groups.

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Climatological Characteristics of Arctic and Antarctic Surface-Based Inversions

Journal of Climate ◽

10.1175/2011jcli4004.1 ◽

2011 ◽

Vol 24 (19) ◽

pp. 5167-5186 ◽

Cited By ~ 76

Author(s):

Yehui Zhang ◽

Dian J. Seidel ◽

Jean-Christophe Golaz ◽

Clara Deser ◽

Robert A. Tomas

Keyword(s):

Climate Models ◽

Climate Model ◽

Surface Ozone ◽

Climatic Variability ◽

Elevation Angle ◽

Climate Feedback ◽

The Arctic ◽

Spatial And Temporal Variability ◽

Seasonal And Diurnal Variations ◽

Radiosonde Observation

Surface-based inversions (SBIs) are frequent features of the Arctic and Antarctic atmospheric boundary layer. They influence vertical mixing of energy, moisture and pollutants, cloud formation, and surface ozone destruction. Their climatic variability is related to that of sea ice and planetary albedo, important factors in climate feedback mechanisms. However, climatological polar SBI properties have not been fully characterized nor have climate model simulations of SBIs been compared comprehensively to observations. Using 20 years of twice-daily observations from 39 Arctic and 6 Antarctic radiosonde stations, this study examines the spatial and temporal variability of three SBI characteristic—frequency of occurrence, depth (from the surface to the inversion top), and intensity (temperature difference over the SBI depth)—and relationships among them. In both polar regions, SBIs are more frequent, deeper, and stronger in winter and autumn than in summer and spring. In the Arctic, these tendencies increase from the Norwegian Sea eastward toward the East Siberian Sea, associated both with (seasonal and diurnal) variations in solar elevation angle at the standard radiosonde observation times and with differences between continental and maritime climates. Two state-of-the-art climate models and one reanalysis dataset show similar seasonal patterns and spatial distributions of SBI properties as the radiosonde observations, but with biases in their magnitudes that differ among the models and that are smaller in winter and autumn than in spring and summer. SBI frequency, depth, and intensity are positively correlated, both spatially and temporally, and all three are anticorrelated with surface temperature.

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Characteristics of gravity waves generated in a convective and a non-convective environment revealed from hourly radiosonde observation under CPEA-II campaign

Annales Geophysicae ◽

10.5194/angeo-29-2259-2011 ◽

2011 ◽

Vol 29 (12) ◽

pp. 2259-2276 ◽

Cited By ~ 5

Author(s):

S. K. Dhaka ◽

R. Bhatnagar ◽

Y. Shibagaki ◽

H. Hashiguchi ◽

S. Fukao ◽

...

Keyword(s):

Gravity Waves ◽

Zonal Wind ◽

Wind Shear ◽

Radiosonde Data ◽

Strong Wind ◽

Mean Flow ◽

Vertical Wavelength ◽

Short Period ◽

Radiosonde Observation ◽

Wind Shears

Abstract. Analyses of hourly radiosonde data of temperature, wind, and relative humidity during four days (two with convection and two with no convection) as a part of an intensive observation period in CPEA-2 campaign over Koto Tabang (100.32° E, 0.20° S), Indonesia, are presented. Characteristics of gravity waves in terms of dominant wave frequencies at different heights and their vertical wavelengths are shown in the lower stratosphere during a convective and non-convective period. Gravity waves with periods ~10 h and ~4–5 h were found dominant near tropopause (a region of high stability) on all days of observation. Vertical propagation of gravity waves were seen modified near heights of the three identified strong wind shears (at ~16, 20, and 25 km heights) due to wave-mean flow interaction. Between 17 and 21 km heights, meridional wind fluctuations dominated over zonal wind, whereas from 22 to 30 km heights, wave fluctuations with periods ~3–5 h and ~8–10 h in zonal wind and temperature were highly associated, suggesting zonal orientation of wave propagation. Gravity waves from tropopause region to 30 km heights were analyzed. In general, vertical wavelength of 2–5 km dominated in all the mean-removed (~ weekly mean) wind and temperature hourly profiles. Computed vertical wavelength spectra are similar, in most of the cases, to the source spectra (1–16 km height) except that of zonal wind spectra, which is broad during active convection. Interestingly, during and after convection, gravity waves with short vertical wavelength (~2 km) and short period (~2–3 h) emerged, which were confined in the close vicinity of tropopause, and were not identified on non-convective days, suggesting convection to be the source for them. Some wave features near strong wind shear (at 25 km height) were also observed with short vertical wavelengths in both convective and non-convective days, suggesting wind shear to be the sole cause of generation and seemingly not associated with deep convection below. A drop in the temperature up to ~4–5 K (after removal of diurnal component) was observed at ~16 km height near a strong wind shear (~45–55 m s−1 km−1) during active period of convection.

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Simultaneous Observations of Cirrus Clouds with a Millimeter-Wave Radar and the MU Radar

Journal of Applied Meteorology ◽

10.1175/jam2191.1 ◽

2005 ◽

Vol 44 (3) ◽

pp. 313-323 ◽

Cited By ~ 5

Author(s):

Eiko Wada ◽

Hiroyuki Hashiguchi ◽

Masayuki K. Yamamoto ◽

Michihiro Teshiba ◽

Shoichiro Fukao

Keyword(s):

Millimeter Wave ◽

Three Dimensional ◽

Cirrus Clouds ◽

Vertical Shear ◽

Dimensional Structure ◽

Horizontal Wind ◽

Millimeter Wave Radar ◽

Mu Radar ◽

Wave Radar ◽

Radiosonde Observation

Abstract Observations of frontal cirrus clouds were conducted with the scanning millimeter-wave radar at the Shigaraki Middle and Upper Atmosphere (MU) Radar Observatory in Shiga, Japan, during 30 September–13 October 2000. The three-dimensional background winds were also observed with the very high frequency (VHF) band MU radar. Comparing the observational results of the two radars, it was found that the cirrus clouds appeared coincident with the layers of the strong vertical shear of the horizontal winds, and they developed and became thicker under the condition of the strong vertical shear of the horizontal wind and updraft. The result of the radiosonde observation indicated that Kelvin–Helmholtz instability (KHI) occurred at 8–9-km altitudes because of the strong vertical shear of the horizontal wind. The warm and moist air existed above the 8.5-km altitude, and the cold and dry air existed below the 8.5-km altitude. As a result of the airmass mixing of air above and below the 8.5-km altitudes, the cirrus clouds were formed. The updraft, which existed at 8.5–12-km altitude, caused the development of the cirrus clouds with the thickness of >2 km. By using the scanning millimeter-wave radar, the three-dimensional structure of cell echoes formed by KHI for the first time were successfully observed.

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