A method to estimate concentrations of surface-level particulate matter using satellite-based aerosol optical thickness

We propose a new method to estimate surface-level particulate matter(PM)concentrations by using satellite-retrieved Aerosol Optical Thickness(AOT).This method considers the distribution and variation of Planetary Boundary Layer(PBL)height and relative humidity(RH)at the regional scale.The method estimates surface-level particulate matter concentrations using the data simulated by an atmospheric boundary layer model RAMS and satellite-retrieved AOT.By incorporation MODIS AOT,PBL height and RH simulated by RAMS,this method is applied to estimate the surface-level PM 2.5 concentrations in North China region.The result is evaluated by using 16 ground-based observations deployed in the research region,and the result shows a good agreement between estimated PM 2.5 concentrations and observations,and the coefficient of determination R2 is 0.61 between the estimated PM 2.5 concentrations and the observations.In addition,surface-level PM 2.5 concentrations are also estimated by using MODIS AOT,ground-based LIDAR observations and RH measurements.A comparison between the two estimated PM 2.5 concentrations shows that the new method proposed in this paper is better than the traditional method.The coefficient of determination R2 is improved from 0.32 to 0.62.     

CLDASSD: Reconstructing Fine Textures of the Temperature Field Using Super-Resolution Technology

Before 2008,the number of surface observation stations in China was small.Thus,the surface observation data were too sparse to effectively support the High-resolution China Meteorological Administration’s Land Assimilation System(HRCLDAS)which ultimately inhibited the output of high-resolution and high-quality gridded products.This paper proposes a statistical downscaling model based on a deep learning algorithm in super-resolution to research the above problem.Specifically,we take temperature as an example.The model is used to downscale the 0.0625°×0.0625°,2-m temperature data from the China Meteorological Administration’s Land Data Assimilation System(CLDAS)to 0.01°×0.01°,named CLDASSD.We performed quality control on the paired data from CLDAS and HRCLDAS,using data from 2018 and 2019.CLDASSD was trained on the data from 31 March 2018 to 28 February 2019,and then tested with the remaining data.Finally,extensive experiments were conducted in the Beijing-Tianjin-Hebei region which features complex and diverse geomorphology.Taking the HRCLDAS product and surface observation data as the"true values"and comparing them with the results of bilinear interpolation,especially in complex terrain such as mountains,the root mean square error(RMSE)of the CLDASSD output can be reduced by approximately 0.1℃,and its structural similarity(SSIM)was approximately 0.2 higher.CLDASSD can estimate detailed textures,in terms of spatial distribution,with greater accuracy than bilinear interpolation and other sub-models and can perform the expected downscaling tasks.     

Adaptive filter in SAR interferometry derived DEM

IntroductionRadar interferometry (InSAR) has been suc-cessfully applied to measure the surface topogra-phyin the past two decades[1-4].Since InSARisa coherent technology ,the most i mportant con-straint for the radar echo is coherence . Howev-er ,decorrelation is al ways inevitably introducedby the thermal noise , geometric decorrelation,Doppler centroid decorrelation, volume scatter-ing decorrelation,temporal decorrelation, orbiterror , at mospheric delay , and data processingnoise[5-6]. …     

Decision support for integrated river basin management—Scientific research challenges

Integrated River Basin Management(IRBM)has been a long discussed way to sustainably manage water and land resources;yet,very few examples of effective IRBM are found because there is a lack of sufficient scientific support,as well as institutional accommodation,to successfully implement it.This paper overviews the major challenges with IRBM,the promising scientific approaches for the implementation of IRBM,and the areas of needed research,with considerable issues and experiences from China.It is expected that novel research will draw together disparate disciplines into an integrated scientific framework,upon which better modeling tools,stakeholder involvement,and decision-making support can be built.Cutting-edge new technologies will bring ideas of IRBM forward to theory and finally to practice.The paper will prompt scientists to undertake research to fill in the gaps in the current IRBM knowledge base and provide practitioners guidance on how to incorporate scientifically based information within the IRBM decision process.     

Starch grains from dental calculus reveal ancient plant foodstuffs at Chenqimogou site, Gansu Province

Chenqimogou site, located at the south bank of Tao River, is comprised of a large group of graves dated to ~4000 a BP. For its large scale, unique mortuary system, and abundant of typical artifacts, the site was named one of Top Ten Archaeological Discoveries of 2008 in China. Many intact human skeletons have been excavated from the graves. Three teeth from two adult skeletons excavated from graves M187 and M194 were examined. Forty-eight starch grains were retrieved from dental calculus of three teeth. Six...     

东南亚地区生物体燃烧影响华南地区对流层臭氧垂直分布的个例分析

2001年3月7日与8日在香港与昆明用电化学臭氧探空仪探测到了对流层低层异常的高浓度臭氧分布. 本文使用NCEP（美国环境预报中心）分析资料、中尺度数值模式MM5模拟的大气环流数据、卫星观测的东南亚地区的生物体燃烧状况、气溶胶指数等资料,分析了这段时间的天气形势、大气环流、空气的后向轨迹以及生物体燃烧产生的烟尘的轨迹,结果发现高浓度的臭氧空气来源于有生物体燃烧的中南半岛地区. 燃烧烟尘的轨迹还表明生物体燃烧地区的下风方的对流层低层臭氧的分布会受到上游地区生物体燃烧产物的影响.     

Along-track Calibration of the Zhurong Rover Magnetometer

As part of the Chinese Tianwen-1 mission, the Zhurong Rover began its scientific investigation in the southern Utopia Planitia after its successful landing in 15 May, 2021. The Zhurong Rover magnetometer(RoMAG), one of the six payloads onboard the rover, includes two identical high-sensitivity triaxial fluxgate magnetometers and can implement mobile magnetic measurements on the surface of Mars. Although a rover magnetic compensation procedure was conducted to remove the magnetic interferences pr...     

Long-term seismic network in South China Sea by floating MERMAIDs

Seismic data coverage in ocean regions is sparse, and it is highly challenging to build long-term continuous seismic networks in the oceans due to the restrictions related to the shortage of instruments and great costs. The lack of data coverage limits effective seismic imaging of deep mantle structures beneath the oceans, which cover 70% of the Earth’s surface. The newly developed Mobile Earthquake Recorder in Marine Areas by Independent Drivers(MERMAID) can drift with ocean currents at a speci...