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Impact of 1.5°C and 2.0°C global warming on aircraft takeoff performance in China

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Science Bulletin 2018年第11期63卷 700-707页

作者： Tianjun Zhou Liwen Ren Haiwen Liu Jingwen Lu LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Department of aviation meteorology Civil Aviation University of ChinaTianjin 300300China

Associated with global warming, climate extremes such as extreme temperature will significantly increase. Understanding how climate change will impact the airflights is important to the planning of future flight operations. In this study, the impacts of 1.5 and 2 degree's global warming on the aircraft takeoff performance in China are investigated using a unique climate projection data from an international collaboration project named HAPPI. It is found that the mean summer daily maximum temperature, which is a major factor that affects the flight through changing the aircraft's takeoff weight, will increase significantly with magnitude less than 1.5℃ over most parts of China except for the Tibetan Plateau. The half a degree additional global warming will lead to higher extreme temperature in the arid and semi-arid western China, the Tibetan Plateau and the northeastern China, while the change in eastern China is weak. Five airports including Beijing, Shanghai, Kunming, Lasa and Urumqi will see ～1.0°-2.0℃(1.4°-3.0℃) higher daily maximum temperature under 1.5℃(2.0℃) scenario. The half-degree additional warming will lead to a shift toward higher extreme temperature in these five sites. For both1.5° and 2.0℃ scenarios, the number of weight-restriction days will increase significantly at 3 airports including Beijing, Shanghai, and Lasa. Urumqi will witness an increase of weight-restriction days only in 2.0℃ future.

关键词： Extreme temperature 1.5 and 2 degree's global warming Airflight Weight-restriction days

Study on Moist Potential Vorticity and Symmetric Instabilityduring a Heavy Rain Event Occurred inthe Jiang-Huai Valleys

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Advances in Atmospheric Sciences 1999年第2期16卷 314-321页

作者：寿绍文李耀辉 Nanjing institute of meteorology Nanjing

In the light of the theory on moist potential vorticity (MPV) investigation was undertaken of the 700 hPa vertical (horizontal) component MP1 (MPV2) for the heavy rain event occurring in July 5–6, 1991. Results show that the distribution features of the two components were closely related to the development of a mesoscale cyclone as a rainstorm-causing weather system in the lower troposphere in such a way that the ambient atmosphere of which MPV1 > 0 and MPV2 < 0 with |MPV1| ≥ |MPV2| favored the genesis of conditional symmetric instability (CSI) and that, as indicated by calculations, a CSI sector was really existent in the lower troposphere during the heavy rain happening and contributed greatly to its development.

关键词： Heavy rain Moist potential vorticity (MPV) Conditional symmetric instability

Short-range Climate Prediction Experiment of the Southern Oscillation Index Based on the Singular Spectrum Analysis

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Advances in Atmospheric Sciences 2001年第5期18卷 873-881页

作者：刘健文董佩明 Beijing aviation institute of meteorology Beijing China

The Southern Oscillation Index (SOI) time series is analyzed by means of the singular spectrum analysis (SSA) method with 60-month window length. Two major oscillatory pairs are found in the series whose periods are quasi-four and quasi-two years respectively. The auto-regressive model, which is developed on the basis of the Maximum Entropy Spectrum Analysis, is fitted to each of the 9 leading components including the oscillatory pairs. The prediction of SOI with the 36-month lead is obtained from the reconstruction of these extrapolated series. Correlation coefficient between predicted series and 5 months running mean of observed series is up to 0.8. The model can successfully predict the peak and duration of the strong ENSO event from 1997 to 1998. It's also shown that the proper choice of reconstructed components is the key to improve the model prediction.

关键词： Southern Oscillation Index singular spectrum analysis principal component reconstruction

Conversion Characteristics between Barotropic and Baroclinic Circulations of the SAH in Its Seasonal Evolution

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Advances in Atmospheric Sciences 2000年第1期17卷 129-139页

作者：刘宣飞朱乾根郭品文 Nanjing institute of meteorology Nanjing

In the context of 1958–1997 NCEP/ NCAR re-analyses, the South Asia high (SAH) was divided into two components, barotropic and baroclinic, the former based on mass weighed vertical integration and the latter on the difference between the measured circulation and the barotropic component counterpart, whereupon the barotropic and baroclinic circulation conversion features were addressed of the research SAH during its seasonal variation. Evidence suggests that i) in summer (winter), the SAH is a thermal (dynamical) system, with dominant baroclinicity (barotropicity), either of the components accounting for approximately 70% of the total contribution; ii) as time progresses from winter to summer, accompanied by the barotropic SAH evolving into its baroclinic analog, the SAH is moving under the “ thermal guidance” of its baroclinic component circulation, suggesting that the component circulation precedes the system itself in variation; iii) the reversal happens when it goes from summer to winter, with the SAH displacement under the “ dynamic steering” of its barotropic component circulation. Key words SAH (South Asia high) - Barotropic circulation - Baroclinic circulation - Seasonal variation (1)This work is supported by the National Natural Sciences Foundation of China under Grant No.49735170.

关键词： SAH (South Asia high) Barotropic circulation Baroclinic circulation Seasonal variation

Influence of ENSO Event on the Maintenance of Pacific Storm Track in the Northern Winter

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Advances in Atmospheric Sciences 1999年第4期16卷 630-640页

作者：朱伟军孙照渤 Nanjing institute of meteorology Nanjing

An influence of ENSO event on the maintenance of Pacific storm track in the Northern winter is studied based on the NCEP/ NCAR daily re-analysis data. The result shows that in El Ni?o (La Ni?a) year an increase (decrease) of baroclinicity over the storm track, extension (withdrawal) eastward and southward (westward but northward for its east end) of its position and augmentation (debilitation) of its strength are closely in response to the enhancement (abatement) of eddy heat flux and momentum flux that are associated with the development of the storm track. It thus indicates that ENSO event exerts an important impact on its maintenance and development in the Pacific Ocean.

关键词： ENSO Storm track Baroclinicity

Refractivity estimations from an angle-of-arrival spectrum

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Chinese Physics B 2011年第2期20卷 586-591页

作者：赵小峰黄思训 institute of meteorology PLA University of Science & Technology

This paper addresses the probability of atmospheric refractivity estimation by using field measurements at an array of radio receivers in terms of angle-of-arrival spectrum. Angle-of-arrival spectrum information is simulated by the ray optics model and refractivity is expressed in the presence of an ideal tri-linear profile. The estimation of the refractivity is organized as an optimization problem and a genetic Mgorithm is used to search for the optimal solution from various trial refractivity profiles. Theoretical analysis demonstrates the feasibility of this method to retrieve the refractivity parameters. Simulation results indicate that this approach has a fair anti-noise ability and its accuracy performance is mainly dependent on the antenna aperture size and its positions.

关键词： refractivity estimation angle-of-arrival spectrum ray optics model genetic algorithm

Variational assimilation in combination with a regularization method for sea level pressure retrieval from QuikSCAT scatterometer data Ⅱ:simulation experiment and actual case study

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Chinese Physics B 2011年第12期20卷 510-516页

作者：张亮黄思训沈春施伟来 institute of meteorology PLA University of Science and Technology

The sea level pressure field can be computed from sea surface winds retrieved from satellite microwave scatterometer measurements, based on variational assimilation in combination with a regularization method given in part I of this paper. First, the validity of the new method is proved with a simulation experiment. Then, a new processing procedure for the sea level pressure retrieval is built by combining the geostrophic wind, which is computed from the scatterometer 10-meter wind using the University of Washington planetary boundary layer model using this method. Finally, the feasibility of the method is proved using an actual case study.

关键词： scatterometer sea level pressure variational assimilation regularization QuikSCAT

Ray tracing/correlation approach to estimation of surface-based duct parameters from radar clutter

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Chinese Physics B 2010年第4期19卷 484-491页

作者：赵小峰黄思训盛峥 institute of meteorology PLA University of Science and Technology

This paper describes a technique to estimate surface-based duct parameters by using a simple ray tracing/correlation method. The approach is novel in that it incorporates the Spearman rank-order correlation scheme between the observed surface clutter and the surface ray density for a given propagation path. The simulation results and the real data results both demonstrate the ability of this method to estimate surface-based duct parameters. Compared with the results obtained by a modified genetic algorithm combined with the parabolic wave equation, the results retrieved from the ray tracing/correlation scheme show a minor reduction in accuracy but a great improvement on computation time. Therefore the ray tracing/correlation method might be used as a precursor to more sophisticated and slower techniques, such as genetic algorithm and particle filters, by narrowing the parameter search space and providing a comprehensive and more efficient estimation algorithm.

关键词： ray tracing Spearman rank correlation surface-based duct radar clutter

Application of Tikhonov regularization method to wind retrieval from scatterometer data Ⅱ: cyclone wind retrieval with consideration of rain

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Chinese Physics B 2011年第6期20卷 263-268页

作者：钟剑黄思训费建芳杜华栋张亮 institute of meteorology PLA University of Science and Technology

According to the conclusion of the simulation experiments in paper I, the Tikhonov regularization method is applied to cyclone wind retrieval with a rain-effect-considering geophysical model function （called CMF＋Rain）. The CMF＋Rain model which is based on the NASA scatterometer-2 （NSCAT2） GMF is presented to compensate for the effects of rain on cyclone wind retrieval. With the multiple solution scheme （MSS）, the noise of wind retrieval is effectively suppressed, but the influence of the background increases. It will cause a large wind direction error in ambiguity removal when the background error is large. However, this can be mitigated by the new ambiguity removal method of Tikhonov regularization as proved in the simulation experiments. A case study on an extratropical cyclone of hurricane observed with SeaWinds at 25-km resolution shows that the retrieved wind speed for areas with rain is in better agreement with that derived from the best track analysis for the GMF＋Rain model, but the wind direction obtained with the two-dimensional variational （2DVAR） ambiguity removal is incorrect. The new method of Tikhonov regularization effectively improves the performance of wind direction ambiguity removal through choosing appropriate regularization parameters and the retrieved wind speed is almost the same as that obtained from the 2DVAR.

关键词： scatterometer Tikhonov regularization cyclone wind retrieval rain effects