The Twentieth Century Reanalysis Project
Tóm tắt
The Twentieth Century Reanalysis (20CR) project is an international effort to produce a comprehensive global atmospheric circulation dataset spanning the twentieth century, assimilating only surface pressure reports and using observed monthly sea‐surface temperature and sea‐ice distributions as boundary conditions. It is chiefly motivated by a need to provide an observational dataset with quantified uncertainties for validations of climate model simulations of the twentieth century on all time‐scales, with emphasis on the statistics of daily weather. It uses an Ensemble Kalman Filter data assimilation method with background ‘first guess’ fields supplied by an ensemble of forecasts from a global numerical weather prediction model. This directly yields a global analysis every 6 hours as the most likely state of the atmosphere, and also an uncertainty estimate of that analysis.
The 20CR dataset provides the first estimates of global tropospheric variability, and of the dataset's time‐varying quality, from 1871 to the present at 6‐hourly temporal and 2° spatial resolutions. Intercomparisons with independent radiosonde data indicate that the reanalyses are generally of high quality. The quality in the extratropical Northern Hemisphere throughout the century is similar to that of current three‐day operational NWP forecasts. Intercomparisons over the second half‐century of these surface‐based reanalyses with other reanalyses that also make use of upper‐air and satellite data are equally encouraging.
It is anticipated that the 20CR dataset will be a valuable resource to the climate research community for both model validations and diagnostic studies. Some surprising results are already evident. For instance, the long‐term trends of indices representing the North Atlantic Oscillation, the tropical Pacific Walker Circulation, and the Pacific–North American pattern are weak or non‐existent over the full period of record. The long‐term trends of zonally averaged precipitation minus evaporation also differ in character from those in climate model simulations of the twentieth century. Copyright © 2011 Royal Meteorological Society and Crown Copyright.
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Tài liệu tham khảo
Adam WK, 2005, Lange Messreihen zur Wetter‐ und Klimaforschung am Meteorologischen Observatorium Lindenberg, Promet, 31, 159
AlpertJC.2004.‘Sub‐grid scale mountain blocking at NCEP’. InProceedings of 20th Conference on WAF 16th conference on NWP Seattle WA 10–15 January 2004 P2.4. Amer. Meteorol. Soc: Boston.
Bengtsson L, 1982, FGGE four‐dimensional data assimilation at ECMWF, Bull. Amer. Meteorol. Soc., 63, 29
Brunet M, 2008, MEDARE: Proceedings of the international workshop on rescue and digitization of climate records in the Mediterranean basin
Climate Change Science Program.2003.Strategic Planfor the US Climate Change Science Program.US Climate Change Science Program: Washington DC. Available fromhttp://www.climatescience.gov/Library/stratplan2003/final/ccspstratplan2003‐all.pdf.
Climate Change Science Program.2008a.Revised ResearchPlan for the US Climate Change Science Program. US Climate Change Science Program: Washington DC. Available fromhttp://www.climatescience.gov/Library/stratplan2008/.
Climate Change Science Program, 2008, Reanalysis of Historical Climate Data for Key Atmospheric Features: Implications for Attribution of Causes of Observed Change., 156
CompoGP WhitakerJS SardeshmukhPD.2008. ‘The 20th Century Reanalysis Project.’ InProceedings of theThird WCRP International Conference on Reanalysis TheUniversity of Tokyo Japan. 28 Jan–1 Feb 2008.Available athttp://wcrp.ipsl.jussieu.fr/Workshops/Reanalysis2008/Documents/V5‐511_ea.pdf.
Daley R., 1991, Atmospheric Data Analysis
Diamond H, 1938, Comparison of soundings with radio‐meteorographs, aerographs and meteorographs, Bull. Amer. Meteorol. Soc., 19, 129, 10.1175/1520-0477-19.4.129
Easterling DR, 2008, Weather and Climate Extremes in a Changing Climate. Regions of Focus: North America, Hawaii, Caribbean, and US Pacific Islands
GCOS.2010.Implementation plan for the globalobserving system for climate in support of the UNFCCC(2010 Update). WMO‐IOC‐UNEP‐ICS GOOS‐184 GTOS‐76 GCOS‐138 WMO TD‐1523. World Meteorological Organization: Geneva Switzerland. Available athttp://www.wmo.int/pages/prog/gcos/Publications/gcos‐138.pdf.
Gibson JK, 1997, ‘ERA description’.
Group on Earth Observations.2005.The Global Earth ObservationSystem of Systems 10‐year Implementation Plan. Available athttp://earthobservations.org/documents/10‐Year Implementation Plan.pdf.
HouY MoorthiS CompanaK.2002. ‘Parameterization of solar radiation transfer in NCEP models’. Office Note 441. NCEP: Washington DC. Available fromhttp://www.emc.ncep.noaa.gov/officenotes/FullTOC.html#2000.
JuangH‐M.2005. ‘Discrete generalized hybrid vertical coordinates by a mass energy and angular momentum conserving vertical finite‐differencing scheme’. Office Note 445. NCEP: Washington DC. Available fromhttp://www.emc.ncep.noaa.gov/officenotes/FullTOC.html#2000.
Kocin P, 2004, Northeast Snowstorms. American Meteorological Society, Meteorol. Monogr., 32, 2
LottN VoseR Del GrecoSA RossTF WorleyS ComeauxJ.2008.‘The Integrated Surface Database: Partnerships and progress.’InProceedings of 88th AMS Annual Meeting 20–25 January 2008 New Orleans Louisiana combined preprints (CD‐ROM) Amer. Meteorol. Soc: Boston MA. Available fromhttp://www1.ncdc.noaa.gov/pub/data/ish/ams‐isd‐jan08.pdf.
MoorthiS PanH‐L CaplanP.2001. ‘Changes to the 2001 NCEP operational MRF/AVN global analysis/forecast system’. Technical Procedures Bulletin 484 NOAA NWS: Silver Spring MD. Available fromhttp://www.nws.noaa.gov/om/tpb/484.htm.
National Antarctic Expedition, 1913, Meteorology Part II: Comprising daily synchronous charts 1 October 1901 to 31 March 1904
National Centers for Environmental Prediction.2010. ‘Model performance statistics’. NOAA NCEP: Washington DC.http://www.emc.ncep.noaa.gov/gmb/STATS/STATS.html.
PloshayJJ WhiteR MiyakodaK.1983.‘FGGE level III‐b daily global analyses Part I’. NOAA Data Report ERL GFDL‐1.
Przybylak R., 2009, The Polish Climate in the European Context: An Historical Overview.
RieneckerMM SuarezMJ TodlingR BacmeisterJ TakacsL LiuH‐C GuW SienkiewiczM KosterRK GelaroR StajnerI NielsenJE.2008.‘The GEOS‐5 data assimilation system—Documentation ofversions 5.0.1 and 5.1.0 and 5.2.0’. NASA Technical Report Series on Global Modeling and Assimilation NASA/T‐2008‐104606 27. NASA Goddard Space Flight Center: Greenbelt MA.
RoecknerE ArpeK BengtssonL ChristophM ClaussenM DümenilL EschM GiorgettaM SchleseU SchulzweidaU.1996.‘The atmospheric general circulation model ECHAM4: Model description and simulation of present‐day climate’. Report 218 Max‐Planck Institut für Meteorologie: Hamburg Germany.
SimmonsA UppalaS DeeD KobayashiS.2007.‘ERA‐Interim: New ECMWF reanalysis products from 1989 onwards’. Newsletter 110 ECMWF: Reading UK.
TaylorKE WilliamsonD ZwiersF.2000. ‘The sea surface temperature and sea‐ice concentration boundary conditions of AMIP II simulations’. Report 60 Program for Climate Model Diagnosis and Intercomparison. Lawrence Livermore National Laboratory: Livermore California. Available fromhttp://www‐pcmdi.llnl.gov/projects/amip/AMIP2EXPDSN/BCS/amip2bcs.php.
ThépautJ‐N.2006. ‘Assimilating only surface‐pressure observations in 3‐ and 4D‐Var’. InProceedings ofECMWF/GEO Workshop on Atmospheric Re‐analysis Reading UK. 19–22 June 2006. Available fromhttp://www.ecmwf.int/publications/library/ecpublications/_pdf/workshop/2006/Reanalysis/Thepaut.pdf.
Wexler H, 1947, Results of the Wartime Historical and Normal Map Program, Bull. Amer. Meteorol. Soc., 28, 175, 10.1175/1520-0477-28.4.175
YinX GleasonBE CompoGP MatsuiN VoseRS.2008. ‘The International Surface Pressure Databank (ISPD) land component version 2.2’. National Climatic Data Center: Asheville NC. Available fromftp://ftp.ncdc.noaa.gov/pub/data/ispd/doc/ISPD2_2.pdf.