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Use of Total Precipitable Water Classification of A Priori Error and Quality Control in atmospheric Temperature and Water Vapor sounding Retrieval

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Advances in atmospheric Sciences 2012年第2期29卷 263-273页

作者： Eun-Han KWON Elisabeth WEISZ School of Earth and Environmental Sciences Seoul National University Seoul 151-747 Korea Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-Madison1225 West Dayton Street Madison WI 53706 USA

This study investigates the use of dynamic a priori error information according to atmospheric moistness and the use of quality controls in temperature and water vapor profile retrievals from hyperspectral infrared （IR） sounders. Temperature and water vapor profiles are retrieved from atmospheric InfraRed Sounder （AIRS） radiance measurements by applying a physical iterative method using regression retrieval as the first guess. Based on the dependency of first-guess errors on the degree of atmospheric moistness, the a priori first-guess errors classified by total precipitable water （TPW） are applied in the AIRS physical retrieval procedure. Compared to the retrieval results from a fixed a priori error, boundary layer moisture retrievals appear to be improved via TPW classification of a priori first-guess errors. Six quality control （QC） tests, which check non-converged or bad retrievals, large residuals, high terrain and desert areas, and large temperature and moisture deviations from the first guess regression retrieval, are also applied in the AIRS physical retrievals. Significantly large errors are found for the retrievals rejected by these six QCs, and the retrieval errors are substantially reduced via QC over land, which suggest the usefulness and high impact of the QCs, especially over land. In conclusion, the use of dynamic a priori error information according to atmospheric moistness, and the use of appropriate QCs dealing with the geographical information and the deviation from the first-guess as well as the conventional inverse performance are suggested to improve temperature and moisture retrievals and their applications.

关键词： atmospheric sounding AIRS total precipitable water a priori error quality control

Sunglint Impact on atmospheric soundings from Hyperspectral Resolution Infrared Radiances

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Advances in atmospheric Sciences 2012年第3期29卷 455-463页

作者：姚志刚 Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-Madison1225 West Dayton StreetMadisonWI 53706USA

The mid-wave infrared band （3-5 #rn） has been widely used for atmospheric soundings. The sunglint impact on the atmospheric parameter retrieval using this band has been neglected because the reflected radiances in this band are significantly less than those in the visible band. In this study, an investigation of sunglint impact on the atmospheric soundings was conducted with atmospheric InfraRed Sounder ob- servation data from 1 July to 7 July 2007 over the Atlantic Ocean. The impact of sunglint can lead to a brightness temperature increase of 1.0 K for the surface sensitive sounding channels near 4.58 #m. This contamination can indirectly cause a positive bias of 4 g kg-1 in the water vapor retrieval near the ocean surface, and it can be corrected by simply excluding those contaminated channels.

关键词： atmospheric sounding hyperspectral resolution infrared radiances sunglint

Preliminary Study on Direct Assimilation of Cloud-affected Satellite Microwave Brightness Temperatures

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Advances in atmospheric Sciences 2017年第2期34卷 199-208页

作者： Sibo ZHANG Li GUAN Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University of Information Science and TechnologyNanjing 210044China

Direct assimilation of cloud-affected microwave brightness temperatures from AMSU-A into the GSI three-dimensional variational （3D-Var） assimilation system is preliminarily studied in this paper. A combination of cloud microphysics param- eters retrieved by the 1D-Var algorithm （including vertical profiles of cloud liquid water content, ice water content, and rain water content） and atmospheric state parameters from objective analysis fields of an NWP model are used as background fields. Three cloud microphysics parameters （cloud liquid water content, ice water content, and rain water content） are ap- plied to the control variable. Typhoon Halong （2014） is selected as an example. The results show that direct assimilation of cloud-affected AMSU-A observations can effectively adjust the structure of large-scale temperature, humidity and wind anal- ysis fields due to the assimilation of more AMSU-A observations in typhoon cloudy areas, especially typhoon spiral cloud belts. These adjustments, with temperatures increasing and humidities decreasing in the movement direction of the typhoon, bring the forecasted typhoon moving direction closer to its real path. The assimilation of cloud-affected satellite microwave brightness temperatures can provide better analysis fields that are more similar to the actual situation. Furthermore, typhoon prediction accuracy is improved using these assimilation analysis fields as the initial forecast fields in NWP models.

关键词： atmospheric sounding microwave remote sensing data assimilation cloudy radiances GSI

A Miniature Robotic Plane Meteorological sounding System

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Advances in atmospheric Sciences 2004年第6期21卷 890-896页

作者：马舒庆陈洪滨汪改潘毅李强 atmospheric Observation Experimental Base China Meteorological Administration Beijing 100796 Institute of atmospheric Physics Chinese Academy of Sciences Beijing 100029 Institute of Meteorology Sciences Meteorology Bureau of Jiangxi Province Nanchang 330046

This article presents a miniature robotic plane meteorological sounding system (RPMSS), which consists of three major subsystems: a miniature robotic plane, an air-borne meteorological sounding and ?ight control system, and a ground-based system. Take-o? and landing of the miniature aircraft are guided by radio control, and the ?ight of the robotic plane along a pre-designed trajectory is automatically piloted by an onboard navigation system. The observed meteorological data as well as all ?ight information are sent back in real time to the ground, then displayed and recorded by the ground-based computer. The ground-based subsystem can also transmit instructions to the air-borne control subsystem. Good system performance has been demonstrated by more than 300 hours of ?ight for atmospheric sounding.

关键词： miniature Unmanned Aerial Vehicle atmospheric sounding Flight test

Analysis and Test on Influence Factors of Dew Drop Condensation in Dew Point Hygrometer

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Journal of Quantum Computing 2019年第1期1卷 29-39页

作者： Shijun Zhao Xiaoying Chen Xiaolei Wang Wenming Ji Zhonghua Dai Institute of Meteorology and Oceanography National University of Defense TechnologyNanjing211101China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters University of Information Science&TechnologyNanjing210044China College of Mechanical&Electrical Engineering Sanjiang UniversityNanjing210012China No.95875 of PLA Jiuquan735018China

The condensation process of dew droplets is influenced by many factors. Adew point condensation image observation system was built to improve the responsespeed of dew point detector under different measuring conditions. The basic mechanismof dew drop condensation growth was studied and the influence of various factors on thedew drop growth rate were analyzed. And the accuracy of the influence results wasverified based on the improved Hough transform circle detection. The results show thatthe growth rate of dew droplets is affected by ambient temperature, dew pointtemperature, mirror temperature and air velocity. The observed variation of the averageradius of dew droplets is consistent with the theoretical calculations. The maximumradius error is less than 4 μm, the initial error is larger, and the error oscillates in themiddle and late stages of condensation. The establishment of condensation mechanism ishelpful to solve the problem in fast determination of dew point temperature under thecold start of dew point meter, and to improve the response speed.

关键词： atmospheric sounding dew point hygrometer dew droplet condensationgrowth mechanism