Open Access
Evaluation of Atmospheric Precipitable Water from Reanalysis Products Using Homogenized Radiosonde Observations over China
Tianbao Zhao,Juanhuai Wang,Aiguo Dai,Aiguo Dai +3 more
- Vol. 2015
Reads0
Chats0
TLDR
In this paper, the authors evaluated the reliability and consistencies of multidecadal atmospheric reanalysis products and found that most of the reanalyses reproduce well the observed long-term atmospheric precipitable water (PW) changes and interannual variations over China.Abstract:
Many multidecadal atmospheric reanalysis products are available now, but their consistencies and reliability are far from perfect. In this study, atmospheric precipitable water (PW) from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR), NCEP/Department of Energy (DOE), Modern Era Retrospective-Analysis for Research and Applications (MERRA), Japanese 55 year Reanalysis (JRA-55), JRA-25, ERA-Interim, ERA-40, Climate Forecast System Reanalysis (CFSR), and 20th Century Reanalysis version 2 is evaluated against homogenized radiosonde observations over China during 1979–2012 (1979–2001 for ERA-40). Results suggest that the PW biases in the reanalyses are within ∼20% for most of northern and eastern China, but the reanalyses underestimate the observed PW by 20%–40% over western China and by ∼60% over the southwestern Tibetan Plateau. The newer-generation reanalyses (e.g., JRA25, JRA55, CFSR, and ERA-Interim) have smaller root-mean-square error than the older-generation ones (NCEP/NCAR, NCEP/DOE, and ERA-40). Most of the reanalyses reproduce well the observed PW climatology and interannual variations over China. However, few reanalyses capture the observed long-term PW changes, primarily because they show spurious wet biases before about 2002. This deficiency results mainly from the discontinuities contained in reanalysis relative humidity fields in the middle-lower troposphere due to the wet bias in older radiosonde records that are assimilated into the reanalyses. An empirical orthogonal function (EOF) analysis revealed two leading modes that represent the long-term PW changes and El Nino–Southern Oscillation-related interannual variations with robust spatial patterns. The reanalysis products, especially the MERRA and JRA-25, roughly capture these EOF modes, which account for over 50% of the total variance. The results show that even during the post-1979 satellite era, discontinuities in radiosonde data can still induce large spurious long-term changes in reanalysis PW and other related fields. Thus, more efforts are needed to remove spurious changes in input data for future long-term reanalyses.read more
Citations
More filters
Recent Changes in Tropospheric Water Vapor over the Arctic
TL;DR: In this paper, changes in tropospheric water vapor over the Arctic were examined for the period 1979 to 2010 using humidity and temperature data from nine high latitude radiosonde stations north of 70°N with nearly complete records, and from six atmospheric reanalyses.
Journal Article
An Intercomparison between NCEP Reanalysisand Observed Data over China
TL;DR: In this article, an intercomparison and analysis by interpolation is made between the two types of NCEP reanalysis dataset (NCEPI and nCEPII) and station observed monthly land surface mean temperature and precipitation data over China during the period 1989~1998.
Reliability Analyses of Anomalies of NCEP/NCAR Reanalyzed Wind Speed and Surface Air Temperature in Climate Change Research in China
TL;DR: In this paper, the authors describe a dense-in-eastern-and-sparse-inwestern (DINW) scenario, where dense environments are dense and sparse in nature.
References
More filters
Journal ArticleDOI
The NCEP/NCAR 40-Year Reanalysis Project
Eugenia Kalnay,Masao Kanamitsu,Robert Kistler,William D. Collins,D.G. Deaven,L. S. Gandin,M. Iredell,Suranjana Saha,Glenn H. White,John S. Woollen,Yuejian Zhu,Muthuvel Chelliah,Wesley Ebisuzaki,Wayne Higgins,John E. Janowiak,Kingtse C. Mo,Chester F. Ropelewski,Julian X. L. Wang,Ants Leetmaa,Richard W. Reynolds,Roy L. Jenne,Dennis Joseph +21 more
TL;DR: The NCEP/NCAR 40-yr reanalysis uses a frozen state-of-the-art global data assimilation system and a database as complete as possible, except that the horizontal resolution is T62 (about 210 km) as discussed by the authors.
Journal ArticleDOI
The ERA-Interim reanalysis: configuration and performance of the data assimilation system
Dick Dee,S. Uppala,Adrian Simmons,Paul Berrisford,Paul Poli,Shinya Kobayashi,Ulf Andrae,Magdalena Balmaseda,Gianpaolo Balsamo,Peter Bauer,Peter Bechtold,Anton Beljaars,L. van de Berg,Jean Bidlot,Niels Bormann,C. Delsol,Rossana Dragani,Manuel Fuentes,Alan J. Geer,Leopold Haimberger,Sean Healy,Hans Hersbach,Elías Hólm,Lars Isaksen,P. Kallberg,Martin Köhler,Marco Matricardi,A. P. McNally,B. M. Monge-Sanz,Jean-Jacques Morcrette,B.-K. Park,Carole Peubey,P. de Rosnay,Christina Tavolato,Jean-Noël Thépaut,Frederic Vitart +35 more
TL;DR: ERA-Interim as discussed by the authors is the latest global atmospheric reanalysis produced by the European Centre for Medium-Range Weather Forecasts (ECMWF), which will extend back to the early part of the twentieth century.
Journal ArticleDOI
Estimates of the Regression Coefficient Based on Kendall's Tau
TL;DR: In this article, a simple and robust estimator of regression coefficient β based on Kendall's rank correlation tau is studied, where the point estimator is the median of the set of slopes (Yj - Yi )/(tj-ti ) joining pairs of points with ti ≠ ti.
Journal ArticleDOI
The ERA‐40 re‐analysis
S. Uppala,Per Kållberg,Adrian Simmons,U. Andrae,V. da Costa Bechtold,M. Fiorino,J. K. Gibson,J. Haseler,A. Hernandez,Graeme Kelly,Xiaoming Li,Kazutoshi Onogi,Sami Saarinen,N. Sokka,Richard P. Allan,Richard P. Allan,Erik Andersson,Klaus Arpe,Magdalena Balmaseda,Anton Beljaars,L. van de Berg,Jean Bidlot,Niels Bormann,S. Caires,Frédéric Chevallier,A. Dethof,M. Dragosavac,Michael Fisher,Manuel Fuentes,Stefan Hagemann,Elías Hólm,Brian J. Hoskins,Lars Isaksen,Peter A. E. M. Janssen,Roy L. Jenne,A. P. McNally,Jean-François Mahfouf,Jean-Jacques Morcrette,Nick Rayner,Roger Saunders,P. Simon,Andreas Sterl,Kevin E. Trenberth,A. Untch,Drasko Vasiljevic,Pedro Viterbo,John S. Woollen +46 more
TL;DR: ERA-40 is a re-analysis of meteorological observations from September 1957 to August 2002 produced by the European Centre for Medium-Range Weather Forecasts (ECMWF) in collaboration with many institutions as mentioned in this paper.