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Mapping floods due to Hurricane Sandy using NPP VIIRS and ATMS data and geotagged Flickr imagery

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International Journal of Digital earth 2016年第5期9卷 427-441页

作者： Donglian Sun Sanmei Li Wei Zheng Arie Croitoru Anthony Stefanidis Mitchell Goldberg Department of Geography and Geoinformation Science George Mason UniversityFairfaxVAUSA noaa JPSS Program Office LanhamMDUSA

In this study,we present an approach to estimate the extent of large-scale coastal floods caused by Hurricane Sandy using passive optical and microwave remote sensing *** approach estimates the water fraction from coarse-resolution VIIRS and ATMS data through mixed-pixel linear *** on the water fraction difference,using the physical characteristics of water inundation in a basin,the flood map derived from the coarse-resolution VIIRS and ATMS measurements was extrapolated to a higher spatial resolution of 30 m using topographic *** is found that flood map derived from VIIRS shows less inundated area than the Federal emergency Management Agency(FeMA)flood map and the ground *** bias was mainly caused by the time difference in *** is because VIIRS can only detect flood under clear conditions,while we can only find some clear-sky data around the New York area on 4 November 2012,when most flooding water already ***,microwave measurements can penetrate through clouds and sense surface water bodies under clear-or-cloudy *** therefore developed a new method to derive flood maps from passive microwave ATMS *** evaluate the flood mapping method,the corresponding ground observations and the FeMA storm surge flooding(SSF)products are *** results show there was good agreement between our ATMS and the FeMA SSF flood areas,with a correlation of ***,we compared our results to geotagged Flickr contributions reporting flooding,and found that 95%of these Flickr reports were distributed within the ATMS-derived flood area,supporting the argument that such crowd-generated content can be valuable for remote sensing ***,the methodology presented in this paper was able to produce high-quality and high-resolution flood maps over largescale coastal areas.

关键词： coastal flood hurricane water fraction high-resolution flood mapping VIIRS ATMS

Subseasonal features of the Asian summer monsoon in the NCeP climate forecast system

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Acta Oceanologica Sinica 2008年第3期27卷 88-103页

作者： Song YANG WeN Min R Wayne HIGGINS noaa＇s Climate Prediction Center Camp Springs Maryland 20746 USA Chinese Academy of Meteorological Sciences Beijing 100081 China

The operational climate forecast system （CFS） of the US National Centers for environmental Prediction provides climate predictions over the world, and CFS products are becoming an important source of information for regional climate predictions in many Asian countries where monsoon climate dominates. Recent studies have shown that, on monthly-to-seasonal time-scales, the CFS is highly skillful in simulating and predicting the variability of the Asian monsoon. The higher-frequency variability of the Asian summer monsoon in the CFS is analyzed, using output from a version with a spectral triangular truncation of 126 waves in horizontal and 64 sigma layers in vertical, focusing on synoptic, quasi-biweekly, and intraseasonal time-scales. The onset processes of different regional monsoon components were investigated within Asia. Although the CFS generally overestimates variability of monsoon on these time-scales, it successfully captures many major features of the variance patterns, especially for the synoptic timescale. The CFS also captures the timing of summer monsoon onsets over India and the Indo-China Peninsula. However, it encounters difficulties in simulating the onset of the South China Sea monsoon. The success and failure of the CFS in simulating the onset of monsoon precipitation can also be seen from the associated features of simulated atmospheric circulation processes. Overall, the CFS is capable of simulating the synoptic-to-intraseasonal variability of the Asian summer monsoon with skills. As for seasonal-tointerannual time-scales shown previously, the model is expected to possess a potential for skillful predictions of the high-frequency variability of the Asian monsoon.

关键词： Asian summer monsoon onset evolution synoptic-to-intraseasonal variability NCeP climate prediction system

COMPUTeR DeMODULATION TeCHNIQUe FOR A DUAL-CHANNeL MICROWAVe raDIOMeTeR

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Advances in Atmospheric Sciences 1986年第2期3卷 189-198页

作者：赵从龙,J. B. Snider,D. C. Hogg Institute of Atmospheric Physics Academia Sinica Beijing noaa/eRL/Wave Propagation Laboratory Boulder Colourado U.S.A. noaa/eRL/Wave Propagation Laboratory Boulder Colourado U.S.A.

The three stairstep output of the video amplifier has now been designed for the noaa/WPL dual-channel radiometer in order to provide an analog input to one A/D converter instead of to two phase-detectors, and the synchronous detection for data and AGC is done in software. We put the new system into the dual-channel radiometer which was set in Boulder Atmospheric Observatory (BAO) to make experiments for three weeks and found the processor reliable and flexible.

关键词： COMPUTeR DeMODULATION TeCHNIQUe FOR A DUAL-CHANNeL MICROWAVe raDIOMeTeR

MeSOSCALe SPeCTra OF THe FRee ATMOSPHeRIC MOTION IN MID-LATITUDe SUMMeR-UNIVeRSALITY AND CONTRIBUTION OF THUNDeRSTORM ACTIVITIeS

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Advances in Atmospheric Sciences 1987年第1期4卷 105-112页

作者：吕达仁,T.e. VanZandt,W.L. Clark Institute of Atmospheric Physics Academia Sinica Beijing noaa/Aeronomy Laboratory Boulder CO. 80303 U.S.A. noaa/Aeronomy Laboratory Boulder CO. 80303 U.S.A.

Meridional and vertical wind velocities of the free atmosphere were observed continuously in mid-latitude summer of 1981 by using Platteville ST radar in the eastern Colorado plains in order to obtain the mesoscale spectra. Power spectra were obtained for both meridional and vertical components at heights of 3.3-7.9 km for meridional and 3.3-17.7 km for vertical. Results show that the "-5/3 law" is a good fit to "meridional" spectra for wave periods ranging from3hr to 2 days which are consistent with other published observations and give further evidence to the existence of a universal -5/3 law in mesoscale atmospheric motions. Results also show that for wave periods shorter than 3 hr （to about 10 min）, the spectra obviously depart from the -5/3 law and reflect the significant contribution of thunderstorm activities which frequently happen in the mid-latitude summer. Mesoscale spectra of vertical velocity show some characteristics of gravity waves. The mechanism of the observed spectra is discussed.

关键词： MeSOSCALe SPeCTra OF THe FRee ATMOSPHeRIC MOTION IN MID-LATITUDe SUMMeR-UNIVeRSALITY AND CONTRIBUTION OF THUNDeRSTORM ACTIVITIeS

Changes in South Asian monsoon: New high-resolution paleoclimatic records from Tibet, China

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Chinese Science Bulletin 2000年第1期45卷 87-91页

作者： J.T.Overpeck LIU Kambiu J.T.Overpeck Department of Geography and Anthropology Louisiana State UniversityBaton RougeLA 70803USANOAA Paleoclimatology ProgramNational Geophysical Data CenterBoulderCO 80303USANOAA Paleoclimatology Program National Geophysical Data Center Boulder CO 80303 USA

High-resolution pollen records from 6 small lakes in the Tibetan Plateau provided the details of evolution of South Asian monsoon since the Last Glacial Maximum. Prior to 16 kaBP, the region was a desert-steppe characterized by cold and dry climates, the January temperature was 7 -10℃lower than that of present and the annual precipitation only accounted for 40% of the present. The temperature and precipitation increased gradually and trees began to live in the region after 12 kaBP, but during the interval from 9.2 to 6.3 kaBP, forest and forest-meadow appeared occasionally. From 8 to 5 kaBP, both January and July temperature was 2-3℃ higher and annual precipitation was also about 200 mm higher than that of the present. After 5 kaBP, temperature and precipitation decreased linearly and steppe vegetation began to degenerate.

关键词： South Asian monsoon pollen records paleovegetation and paleoclimate Tibet.

Wave parameters retrieval for dual-polarization C-band synthetic aperture radar using a theoretical-based algorithm under cyclonic conditions

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Acta Oceanologica Sinica 2019年第5期38卷 21-31页

作者： Yingying Ding Juncheng Zuo Weizeng Shao Jian Shi Xinzhe Yuan Jian Sun Jiachen Hu Xiaofeng Li Marine Science and Technology College Zhejiang Ocean University College of Meteorology and Oceanography National University of Defense Technology National Satellite Ocean Application Service Ministry of Natural Resources Physical Oceanography Laboratory Ocean University of China Global Science and Technology National Oceanic and Atmospheric Administration (NOAA) National Environmental Satellite Data and Information Service (NOAA)

Theoretical-based ocean wave retrieval algorithms are applied by inverting a synthetic aperture radar(SAR)intensity spectrum into a wave spectrum, that has been developed based on a SAR wave mapping mechanism. In our previous studies, it was shown that the wave retrieval algorithm, named the parameterized first-guess spectrum method(PFSM), works for C-band and X-band SAR at low to moderate sea states. In this work, we investigate the performance of the PFSM algorithm when it is applied for dual-polarization c-band sentinel-1(S-1) SAR acquired in extra wide-swath(eW) and interferometric wide-swath(IW) mode under cyclonic *** winds are retrieved from six vertical-horizontal(VH) polarization S-1 SAR images using the c-band crosspolarization coupled-parameters ocean(C-3 PO) model and then wave parameters are obtained from the image at the vertical-vertical(VV) polarization channel. significant wave height(SWH) and mean wave period(MWP) are compared with simulations from the WAVeWATCH-III(WW3) model. The validation shows a 0.69 m root mean square error(RMSe) of SWH with a –0.01 m bias and a 0.62 s RMSe of MWP with a –0.17 s bias. Although the PFSM algorithm relies on a good quality SAR spectrum, this study confirms the applicability for wave retrieval from an S-1 SAR image. Moreover, it is found that the retrieved results have less accuracy on the right sector of cyclone eyes where swell directly affects strong wind-sea, while the PFSM algorithm works well on the left and rear sectors of cyclone eyes where the interaction of wind-sea and swell is relatively poor.

关键词： wave parameters synthetic aperture radar cyclonic condition

effects of clouds, sea surface temperature, and its diurnal variation on precipitation efficiency

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Chinese Physics B 2013年第9期22卷 456-464页

作者：沈新勇庆涛李小凡 Key Laboratory of Meteorological Disaster of Ministry of education Nanjing University of Information Science and Technology noaa/NeSDIS/Center for Satellite Applications and Research College ParkMaryland 20740USA

The effects of clouds, sea surface temperature, and its diurnal variation on precipitation efficiency are investigated us ing grid-scale data from nine equilibrium sensitivity cloud-resolving model experiments driven without large-scale vertical velocity. The precipitation efficiencies are respectively defined in surface rainfall, cloud, and rain microphysical budgets. We mathematically and physically demonstrate the relationship between these precipitation efficiencies. The 2 ℃ increases in spatiotemporal invariant sea surface temperature （SST） from 27 ℃ to 29 ℃ and from 29 ℃ to 31 ℃, and the inclusion of diurnal SST difference 1 ℃ and the 1℃ increase in diurnal SST difference generate opposite changes in the precipitation efficiency by changing ice cloud-radiation interactions. The radiative and microphysical processes of ice clouds have opposite effects on the precipitation efficiency because of the rainfall increase associated with the reduction in the saturation mixing ratio caused by the exclusion of radiative effects and the decrease in rainfall related to the reduction in net condensation caused by the exclusion of deposition processes. The radiative effects of water clouds on the precipitation efficiency are statistically insensitive to the radiative effects of ice clouds.

关键词： sea surface temperature diurnal variations clouds precipitation efficiency

Development of S-NPP VIIRS global surface type classification map using support vector machines

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International Journal of Digital earth 2018年第2期11卷 212-232页

作者： Rui Zhang Chengquan Huang Xiwu Zhan Huiran Jin Xiao-Peng Song Department of Geographical Sciences University of MarylandCollege ParkMDUSA Center for Satellite Applications and Research NESDIS/NOAACollege ParkMDUSA

With the launch of the Joint Polar Satellite System(JPSS)/Suomi National Polar-orbiting Partnership(S-NPP)satellite in October 2011,many of the terrestrial remote sensing products generated from Moderate Resolution Imaging Spectroradiometer(MODIS),such as the global land cover map,have been inherited and expanded into the JPSS/S-NPP mission using the new Visible Infrared Imaging radiometer Suite(VIIRS)*** this study,an improved algorithm including the use of a new classifier support vector machines(SVM)classifier was proposed to produce VIIRS surface type *** addition to the new classification algorithm,a new post-processing strategy involving the use of new ancillary data to refine the classification output is *** a result,the new global International Geosphere-Biosphere Programme(IGBP)map based on the 2014 VIIRS surface reflectance data was generated with a 78.5±0.6% overall classification *** new map was compared to a previously delivered VIIRS surface type map,and to the MODIS land cover *** results including the error matrix,overall accuracy,and the user’s and producer’s accuracy suggest the new global surface type map provides similar classification accuracy compared to the old VIIRS surface type map,with higher accuracy achieved in agricultural types.

关键词： Global surface type land cover VIIRS SVM

Using a mesoscale ensemble to predict forecast error and perform targeted observation

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Acta Oceanologica Sinica 2014年第1期33卷 83-91页

作者： DU Jun LI Jun YU Rucong CUI Chunguang National Centers for environmental Prediction(NCeP) National Oceanic and Atmosphereic Administration (NOAA) Chinese Meteorological Administration (CMA) Wuhan Institute of Heavy rain CMA

Using NCeP short range ensemble forecast（SReF） system,demonstrated two fundamental on-going evolutions in numerical weather prediction（NWP） are through ensemble *** evolution is the shift from traditional single-value deterministic forecast to flow-dependent（not statistical） probabilistic forecast to address forecast *** is from a one-way observation-prediction system shifting to an interactive two-way observation-prediction system to increase predictability of a weather *** the first part,how ensemble spread from NCeP SReF predicting ensemble-mean forecast error was evaluated over a period of about a *** result shows that the current capability of predicting forecast error by the 21-member NCeP SReF has reached to a similar or even higher level than that of current state-of-the-art NWP models in predicting precipitation,e.g.,the spatial correlation between ensemble spread and absolute forecast error has reached 0.5 or higher at 87 h（3.5 d） lead time on average for some meteorological *** demonstrates that the current operational ensemble system has already had preliminary capability of predicting the forecast error with usable skill,which is a remarkable achievement as of *** the good spread-skill relation,the probability derived from the ensemble was also statistically reliable,which is the most important feature a useful probabilistic forecast should *** second part of this research tested an ensemble-based interactive targeting（e-BIT） *** other mathematically-calculated objective approaches,this method is subjective or human interactive based on information from an ensemble of forecasts.A numerical simulation study was performed to eight real atmospheric cases with a 10-member,bred vector-based mesoscale ensemble using the NCeP regional spectral model（RSM,a sub-component of NCeP SReF） to prove the concept of this e-BIT *** method seems to work most effective for basic atmospheric st

关键词： NCeP SReF ensemble spread-skill relation targeted observation