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New Data Types Working Document DAO Oce Note Oce Note Series on Global Mo deling and Data Assimilation Richard B Ro o d Head Data Assimilation Oce Goddard Space Flight Center Greenbelt Maryland New Data Typ es Working Do cument Joanna Joiner Rob ert Atlas Steve Blo om Genia Brin Stephen Cohn Arthur Hou Dave Lamich Dave Ledvina Richard Menard LarsPeter Riishjgarrd Richard Ro o d Arlindo da Silva Meta Sienkiewicz Jim Stobie Runhua Yang Data Assimilation Oce Goddard Laboratory for Atmospheres Goddard Space Flight Center Greenbelt Maryland This paper has not been published and should be regarded as an Internal Report from DAO Permission to quote from it should be obtained from the DAO Go ddard Space Flight Center Greenb elt Maryland June Abstract This working do cument describ es activities related to the New Data Typ es Group of the Go ddard Data Assimilation Oce DAO and how these activities are prioritized Included in this do cument are science drivers for new data typ es brief descriptions of assimilation metho dologies including advanced metho dologies b eing explored at the DAO a list of new data typ es b eing considered for assimilation and validation at the DAO and how these data typ es are roughly prioritized This do cument will b e up dated p erio dically Online versions of this do cument are available from ftpdaogsfcnasagovpubofficenotesonpsZ postscript Contents List of Tables Intro duction Scientic drivers Overview Hydrological Cycle LandSurfaceAtmosphere Interaction OceanSurfaceAtmosphere Interaction Radiation Clouds Aerosols and Greenhouse Gases Atmospheric Circulation Trop ospheric circulation and temp erature Stratospheric circulation and temp erature Constituents Assimilation Metho dology Statistical Analysis Direct radiance assimilation Traditional retrieval assimilation Consistent Assimilation of Retrieved Data CARD Physical Space Phase Space Implementation Data ow and Computational Issues Instrument Team Interaction Priorities Priorities group ed by science topic Temp erature Moisture Assimilation ConvectivePrecip Retrieval Assimilation Land Surface Ocean Surface Constituents Wind prole Aerosols Priorities group ed by satellite Priorities group ed by use in GEOS References App endix App endix A Acronyms App endix B Instruments and Satellites List of Tables Seminar Sp eakers for New Data Typ es Group Visitors Consultants and Collab orators Priorities for assimilating temp erature data Priorities for assimilating water vap or data Priorities for assimilating convective retrievals Priorities for assimilating landsurface data Priorities for assimilating o ceansurface data Priorities for assimilating ozone data Priorities for assimilating CO data Priorities for assimilating wind proles Priorities for use of aerosol data Highpriority data typ es from POES satellite Highpriority data typ es from UARS satellite Highpriority data typ es from TRMM satellite Highpriority data typ es from the ADEOS satellite Highpriority data typ es from EOS AM satellite Highpriority data typ es for rst lo ok system Highpriority data typ es for nal platform Highpriority data typ es for reanalysis andor p o cket analysis Intro duction The mandate of the Data Assimilation Oce DAO at NASAGo ddard is to provide highquality data sets to b e used by the Earth science community to study a numb er of Earth Systems problems As part of the DAO mandate a ma jor eort is b eing undertaken to assimilate new data typ es from current and future instruments Emphasis is given to instruments that will y as part of NASAs Mission to Planet Earth MTPE program particularly those on b oard the Advanced Earth Observing System ADEOS the Tropical Rainfall Measuring Mission TRMM and the Earth Observing System AM EOSAM scheduled for launches in and resp ectively currently this do cument only addresses satellites through EOSAM The instruments ab oard these satellites are de signed to measure quantities related to atmospheric and surface parameters of particular relevance to Earth Systems study More detailed information ab out comp onents of the DAOs GEOS system can b e found in Takacs et al Pfaendtner et al and Schub ert and Ro o d Do cumentation on the DAOs PhysicalSpace Statistical Analysis System PSAS can b e found in da Silva and Guo The eort required to assimilate new data typ es is nontrivial For example at other NWP centers the eort to incorp orate new data typ es has required approximately p ersonyears p er new data typ e and is an ongoing eort New data typ es currently b eing considered for assimilation at the DAO may b e classied into two categories Data typ es from instruments with an assimilation heritage at the DAO and other centers eg TOVS radiances Scatterometer measurements etc Data typ es that do not have a longterm op erational heritage eg precipitation surface wetness etc Data typ es in are considered to b e a higher risk than those in The DAO eort to assimilate new data typ es includes developing advanced assimilation metho dologies that will b e required in order to handle the large volume of data from future instruments Monitoring new data typ es b efore during and after assimilation will b e an imp ortant comp onent of the new data typ es eort The eort will also involve interacting with instrument teams as well as interfacing with other DAO groups such as the those concerned with covariance tuning quality control op erations and development This do cument attempts to dene and prioritize the activities of the DAOs New Data Types group This is a working do cument meaning that it will evolve as exp erience is gained with new data typ es Parts of the do cument are incomplete at this time and will b e revised in the future This do cument will b e used by DAO sta to guide decisions in how resources related to New Data Types will b e allo cated in the present and future It will also provide instrument teams with information ab out what will b e required from them in order to eectively utilize observations in the Go ddard Earth Observing System Data Assimilation System GEOSDAS Details on related topics such as the Kalman ltering eort Observation System Simulation Exp eriments OSSE Observation System Exp eriments OSE and bias correction will app ear elsewhere or will b e incorp orated into the do cument at a later time Do cumentation on related topics can b e found elsewhere monitoring can b e found in da Silva et al b quality control in Dee and Trenholme quality assurance in Schub ert and op erations in Stobie The outline of the do cument is as follows Section describ es the scientic goals that drive the eort to incorp orate new data typ es in the DAOs Data Assimilation System This section b egins with an overview and follows with subsections devoted the hydrological cy cle landsurfaceatmosphere interaction o ceansurfaceatmosphere interaction radiation clouds aerosols greenhouse gases atmospheric circulation and constituents For each scientic driver examples of relevant data typ es are given Section discusses traditional and advanced metho dologies for assimilating data and provides examples of relevant data typ es for each metho d Section describ es several topics related to implementation com putational issues data ow and instrument team interaction Finally new and existing data typ es are prioritized in section Crossreferences of instrument to data typ e scientic driver use in GEOS etc are provided Scientic drivers Overview The NASA Mission to Planet Earth MTPE is a program designed to make use of ground aircraft and satellitebased measurements in order to b etter understand the systems that govern the Earths climate their interactions and their variations NASAs Earth Observ ing System EOS and several other satellite systems are key comp onents of this program Driving the selection of new data typ es in the GEOSDAS is a subset of scientic ob jec tives outlined by the MTPE program the United States Global Change Research Program USGCRP and the Intergovernmental Panel on Climate Change IPCC These ob jectives include improving our understanding of the hydrological cycle interaction b etween the land and o cean surfaces with the atmosphere and transp ort of heat moisture and momen tum the interaction of clouds and aerosols with radiation and its impact on climate chemistry and transp ort of atmospheric constituents such as ozone in b oth the trop
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