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THE N ORTH A MERICAN M ONSOON E XPERIMENT ( NAME ). Briefing for the CLIVAR SSC July 17, 2002 NAME Science Working Group. NAME Science and Implementation Plan: http://www.joss.ucar.edu/name/. U.S. CLIVAR ISSUES FOR NAME.
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THE NORTH AMERICAN MONSOON EXPERIMENT (NAME) Briefing for the CLIVAR SSC July 17, 2002 NAME Science Working Group • NAME Science and Implementation Plan: http://www.joss.ucar.edu/name/
U.S. CLIVAR ISSUES FOR NAME • What is the relative balance of activities between CLIVAR and GEWEX? • How will NAME contribute to the improvement of global climate models? • How will advances in seasonal prediction be pursued? • Has NAME developed partnerships between observationalists and climate modelers to improve the representation of key processes in coupled climate models? • How will NAME address regional-scale (Tier 2) and continental-scale (Tier 3) warm-season precipitation variability and predictability?
OUTLINE • OVERVIEW • What is NAME? • Balance of Activities • CLIVAR/PACS interests in NAME • GEWEX/GAPP interests in NAME • Project Structure/Timeline • NAME MODELING AND DIAGNOSTIC STUDIES • Predictive Capabilities / Science Issues / Observational Needs • Global Modeling – Observations Team • Regional Modeling – Observations Team • Additional Issues and Opportunities • Satellite Precipitation Estimation (TRMM/GPM) and NAME • NAME FIELD CAMPAIGN • Observational Network • International Partnerships
WHAT IS NAME? NAME is an internationally coordinated, joint CLIVAR – GEWEX process study aimed at determining the sources and limits of predictability of warm season precipitation over North America.
NORTH AMERICAN MONSOON EXPERIMENT (NAME) HYPOTHESIS The NAMS provides a physical basis for determining the degree of predictability of warm season precipitation over the region. Topographic and Sea-Land Influence • OBJECTIVES: • Better understanding and • simulation of: • warm season convective • processes in complex terrain • (TIER I); • intraseasonal variability of • the monsoon (TIER II); • response of warm season • circulation and precipitation • to slowly varying boundary • conditions (SST, soil • moisture) (TIER III); • monsoon evolution and • variability (TIER I, II, III). Intraseasonal Variability Boundary Forcing? YEAR (2000+) 00 01 02 03 04 05 06 07 08 Planning --------------| Preparations --------------| Data Collection - - - ----------------| Principal Research ----------------------------------| Data Management -----------------------------------------|
NAME IMPLEMENTATION • Empirical and modeling studies that carry forward the joint PACS/GAPPWarm Season Precipitation Initiative (2000 onward), and initiate new elements. • NAME Field Campaign (JJAS 2004) including build-up, field, analysis and modeling phases.
NAME STATUS • NAME has been endorsed by the WCRP/CLIVAR Variability of the American Monsoons (VAMOS) Panel as the North American Implementation of VAMOS. • The US CLIVAR Pan American Panel has formally recommended that US CLIVAR join with US GEWEX/GAPP and VAMOS to implement NAME as a warm season process study of the North American Monsoon. • NAME is a part of the GEWEX/GAPP Science and Implementation plan, with emphasis on topographic influences on precipitation, hydrology and water resources, and land-surface memory processes.
CLIVAR / PACS NAMS Research • Established enhanced PIBAL upper air sounding network in Mexico and Central America; • Developed improved satellite and in-situ surface climate, precipitation, and upper air data sets; • Implemented real time monsoon monitoring at CPC; • Investigated monsoon climatology and SST-monsoon relationships.
PACS/GAPP North American Warm Season Precipitation Projects • Examining the relative influence of ocean and land surface processes; • Investigating the inverse relationship between precipitation in core monsoon region and over central US*; • Studying antecedent winter influence on monsoon strength*; • Evaluating influence of InterAmericas Seas warm pool variability; • Establishing enhanced raingauge network in Mexico.
CLIVAR/PACS Interests in NAME • To obtain a better understanding and more realistic simulation of the continental-scale NAM and its variability (emphasis on b.c’s); • To demonstrate that observed connections between the leading patterns of climate variability (e.g. ENSO, MJO) and the monsoon are captured in climate models; • To develop partnerships between NAME observationalists and model development experts to improve the representation of key processes in coupled climate models; • To advance the development of the climate observing system in southwestern North America and Central America.
GEWEX / GAPP Components Hydrometerology Orographic Systems Predictability in Monsoonal Systems Predictability in Land Surface Processes Integration of Predictability Into Prediction Systems CEOP: Data and Studies for Model Development Testing of Models in Special Climate Regimes Use of Predictions for Water Resource Management
GAPP-NAME GOAL The GAPP-NAME goal is to determine the sources and limits of predictability of warm season precipitation over North America, with emphasis on the role of the land surface.
GAPP INTERESTS IN NAME • Fine resolution, gauge-only and satellite/gauge merged precipitation products (e.g. for LDAS, Regional Reanalysis and model validation studies); • The role of land in the onset and intensity of the monsoon; • The role of NAMS in the variability of the water budget components over the US and Mexico; • Improved understanding of summer orographic precipitation processes.
NAME PROJECT STRUCTURE • 3-Pronged • NAME Science Working Group (Science Focus) • VAMOS / NAME Project Office (Field Implementation, Data Management, Logistics) • NAME Program Management (Agencies that fund NAME)
NAME SCIENCE WORKING GROUP • NAME science is managed by a SWG that has been approved by the CLIVAR/VAMOS and CLIVAR Pan American panels in consultation with U.S. GEWEX. • The SWG Develops and leads research to achieve NAME objectives • The NAME SWG members: Jorge Amador, Univ. of Costa Rica Rene Lobato, IMTA, Mexico Hugo Berbery, UMD José Meitín, NOAA/ NSSL Rit Carbone, NCAR Chet Ropelewski, IRI Miguel Cortez, SMN,Mexico Jae Schemm, NOAA/CPC Art Douglas, Creighton Univ. Siegfried Schubert, NASA Michael Douglas, NOAA/NSSL Jim Shuttleworth, UAZ Dave Gutzler, UNM Dave Stensrud, NOAA/NSSL Wayne Higgins, NOAA/CPC (Chair) Chidong Zhang, RSMAS
VAMOS / NAME PROJECT OFFICE (Leader:C. B. Emmanuel) 1. Program Planning and Field Implementation: Provide the infrastructure for effective design and implementation of the NAME Field Campaign, including management of field operations. 2. Scientific Data Management: Provide all facets of data collection and dissemination of information for the NAME Program. 3. Logistics: Provide specialized logistics support specifically for the effective implementation of the NAME Field Campaign, including administrative support, workshop coordination and outreach (e.g. webpage, logo)
NAME TIMELINE PHASE 00 01 02 03 04 05 06 07 08 Planning -------------| Build-Up -------------| Data Collection - - - - ------------| Principal Research ------------------------------| Data Management -------------------------------------| Workshop/Conf. Planning (25th CDPW) X SWG (26th CDPW) X SWG (VPM5) X SWG (27th CDPW) X * * Science Workshop X Science Conference X
NAME MODELING AND DIAGNOSTIC STUDIES • GOALS: • Help specify a “ramp-up” strategy for the NAME • Field Campaign. • Provide guidance on needs and priorities for NAME • field observations. • Identify sustained observational requirements for • climate models. • Identify additional process studies necessary to reduce • uncertainties in climate models.
NAME TEAMS • The predictive capabilities, science issues and observational needs of the global and regional/hybrid modeling communities are different. [NEXT] • In response to this, NAME has organized two teams that preserve the modeling-observations linkage for both communities. • This is a strategy to integrate modeling needs for improved warm season precipitation prediction into the planning for NAME observational efforts. • The teams consist of observationalists and modelers with vested interests in specific high-priority issues. • These teams are flexible and can evolve with the CPT concept. • The NAME teams are small and relatively focused. Currently setting goals tied to the 2004 NAME Field Campaign.
GENERAL CIRCULATION MODELS • PREDICTIVE CAPABILITIES: • Some descriptive / predictive ability has been demonstrated in the core monsoon region, but with significant shortcomings. • SCIENCE ISSUES: • To understand why some models give predictability in the core monsoon region. • To diagnose / correct weaknesses. • OBSERVATIONAL NEEDS: • Document basic climatology [esp. precipitation] at appropriate spatial / temporal scales (including the mean diurnal cycle). • Give guidance on weaknesses in convective / boundary layer parameterizations [radar / radiosondes / profilers].
NAME GCM-OBS TEAM In response to these needs, NAME has organized a team (Siegfried Schubert, chair) that links NAME observational efforts to climate model development at GFDL/NASA/NOAA. This team preserves the modeling-observations linkage for NAME and forms the core of a "Climate Process Team”.Currently unfunded; proposal submitted. INITIAL FOCUS: Warm Season Diurnal Cycle over the US and Mexico in AGCM’s PI’s Affiliation Key role ------------------------- ---------- -------- Siegfried Schubert (lead) NASA/GSFC lead and link to NAME Max Suarez NASA/GSFC focus on NSIPP model Arun Kumar NOAA/CPC focus on NCEP model Isaac Held NOAA/GFDL focus on GFDL model
NAME GCM-OBS TEAM STRATEGY: (1) Assess quality of diurnal cycle in several AGCMs; focus on convective / PBL parameterizations. (2) Examine relationships between diurnal circulation and monsoon precipitation: * behavior of the parameterizations (3) Assess the impact of resolution (from 2° lat/lon to about ¼° lat/lon). (4) Carry out process-oriented sensitivity experiments * role of convection and PBL in shaping the diurnal cycle. (5) Exploit observations from NAME as well as ARM and NASA Aqua (especially profile information) to validate parameterizations. (6) Define new observational requirements for improving the parameterizations.
Correlation between ensemble mean and observed precipitation anomalies (JJA 65-97) NCEP-MRF9 GSFC-NSIPP CCM 3.2 • Conclusion: global models have some worthwhile predictive capability in the core monsoon region, but we need to understand why. • These models were driven with observed SST, so this is potential predictability given SST. It does not include any potential predictability one my gain from knowing the land surface boundary conditions.
ANALYZED AND SIMULATED (850-MB WIND AND 200-MB STREAMLINES) Schemm, Zhou and Higgins (2002) EXPERIMENT: Ensembles of 10 / 6 month simulations (May-Oct 1979-2000) with climatological (left) and NCEP reanalysis II (right) soil moisture IC’s using NCEP/MRF; May IC’s. CONCLUSION:The location of the monsoon anticyclone is sensitive to initialized soil moisture.
REGIONAL / HYBRID MODELS • PREDICTIVE CAPABILITIES: • Significant descriptive / predictive ability in “predictive” mode. • Substantial ability to document the NAM when operating in “analysis” mode. • SCIENCE ISSUES: • To improve the representation of convective precipitation, especially in • complex terrain. • OBSERVATIONAL NEEDS: • Improved precipitation observations [gauge, remote sensing] that resolve the diurnal cycle, that sample the topographic influence and that are distributed and integrated. • Investigate topography-induced circulations [radar]. • Document the low-level wind / moisture fields [radiosondes 4-6 times per day] NAMAP is the basis for a second NAME team focused on the modeling-observations link for the regional / hybrid models.
NAME RMM-OBS TEAM • STRATEGY: • Document ability of models to simulate the life cycle and intensity of the monsoon - NAMAP. • Examine topographic influence on convective precipitation. * behavior of the parameterizations • Compare existing parameterization schemes and models using NAME observations for validation. • (4) Improve physical parameterizations (e.g. convection/boundary layer) • that influence precipitation, with a focus on defining the relationship of such parameterizations to topography. • (5) Define new observational requirements for improving the parameterizations
NORTH AMERICAN MONSOON ASSESSMENT PROJECT (NAMAP) STRATEGY: • NAMAP Phase I (D. Gutzler, Chair) • Document ability of models to simulate the NAMS (JJAS 1990). • Protocols (domain, boundary conditions, output format, simulated variables) defined by the modeling community during 2001. • Hosted by the NAME Project Office at UCAR/JOSS: http://www.joss.ucar.edu/name/namap • NAMAP is currently unfunded and voluntary. Current Participants: • Liang (MM5, WRF) Schemm (NCEP MRF) • Mo (RSM) Schubert (NASA NSIPP) • Mitchell / Yang (ETA) Liz Ritchie / Dave Gutzler (MM5) • Kanamitsu (ECPC/RSM) Peter Fawcett • Fox Rabinovitz (NASA Hybrid) • Hahmann (MM5) • Castro / Pielke (RAMS) • Preliminary results will be presented at 27th Climate Diagnostics and Prediction Workshop, George Mason University.
EDAS 925-hPa MOISTURE FLUX AND NASA 3-H PRECIPITATION (JAS 1998-2001) • The GOC LLJ may often be located over the coastal plain, not over the GOC. However, the LLJ may be mixed with the sea-breeze circulation, so semantics may be involved. • This may be a useful hypothesis to test with the NAME in situ sounding network Berbery et al. (2002)
Cumulative Rainfall-Runoff in SMO Basin Gochis and Shuttleworth (2002) (MM5 simulations; July 1999; Chen and Dudhia land surface ) GRELL KAIN-FRITSCH precip precip runoff runoff • Surface runoff is more correlated with individual precip events of sufficient intensity than monthly total precipitation. • This is a critical issue for those seeking to enhance monthly-to-seasonal predictability of water resources. NAME will investigate.
KEY QUESTIONS FOR NAME TEAMS • How well is the life cycle of the monsoon (onset, maintenance and demise) simulated and predicted? • What are the links, if any, between the strength of the monsoon in SW North America and summertime precipitation over the central US? • Can models reproduce the observed summertime precipitation in average years and years with ENSO influence? • How is the evolution of the warm season precipitation regime related to the seasonal evolution of continental and oceanic boundary conditions?
CONTINENTAL-SCALE PRECIPITATION PATTERN • The continental-scale precipitation pattern is characterized by • an out-of-phase relationship between the U.S. Southwest and the U.S. Great Plains. • an in-phase relationship between the U.S. Southwest and the U.S. Southeast. • Phase reversals in this pattern are related to the onset and decay of the monsoon
ONSET OF THE SUMMER RAINS(July – June 1971-2000) • Changes in the tropospheric circulation and divergence (mean vertical motion) are broadly consistent with changes in the continental-scale precipitation pattern: • SW: enhanced DIV, VVEL and PRECIP • GP: suppressed DIV, VVEL and PRECIP CHANGE IN OBSERVED PRECIPITATION [MM DAY-1] CHANGE IN 200 hPA WIND [MS-1] AND DIV[10-6 S-1] H Higgins et al. (1997)
INTERANNUAL VARIABILITY(OBSERVATIONS) • Simultaneous • The continental-scale precipitation pattern is a continental-scale pattern of interannual variability. Anomalously wet (dry) summers in the Southwest U.S. tend to be accompanied by dry (wet) summers in the U.S. Great Plains. • Antecedent • Wet (dry) summers in the Southwest U.S. often follow winters characterized by dry (wet) conditions in the Southwest U.S. and wet (dry) conditions in the Northwest U.S.
COMPOSITE MEAN PRECIPITATION OVER AZ AND NM FOR WET, DRY AND ALL MONSOONS (1963-2000) Higgins et al. (1998) Note: No signal Higgins e t al. (1998) WINTER SPRING ONSET SUMMER
COMPOSITE SUMMER (JJAS) 200-MB WIND, 200-MB STREAMFUNCTION AND PRECIPITATION ANOMALIES* El Niño features: upper-level easterly wind anomalies southward shifted ITCZ upper-level anticyclonic couplet enhanced local Hadley circulation lower-level westerly wind anomalies dry conditions over Mexico Higgins et al. (1999) * Shading indicates anomalies greater than 0.25 mm day-1 10
ADDITIONAL ISSUES / OPPORTUNITIES • POTENTIAL ROLE OF NAME IN TRMM/GPM • ISSUE: • Satellite estimates of precipitation in complex terrainare often inaccurate. • OPPORTUNITIES: • NAME will collect new precipitation data [gauge, radar], so it is a “campaign of opportunity” for TRMM and GPM validation of satellite estimates of precipitation in complex terrain. • TRMM/GPM can leverage NAME observations for algorithm development. • OBSERVATIONAL NEEDS: • Orographic influences on precipitation [gauge, radar]. • Radar estimates of precipitation over the Gulf of California and nearby areas of the Pacific.
NAME FIELD CAMPAIGN Enhanced Precipitation Gauge Network R.V. Ron Brown Radiosondes/PIBALS Radar/Profiling/Radiosondes
BUILD-UP PHASE (1) Establish VAMOS / NAME Project Office for design and implementation of the NAME Field Campaign, data management, and logistics support. (2) Establish NAME cooperative teams for global model-observations and regional model – observations linkages. (3) Plan, integrate and implement NAME networks and conduct site surveys. “Ramp-up” activities in the region. (4) Build National and International NAME Partnerships. (5) Develop an effective education and training program in the region (US activities, International activities).
NAME ENHANCED OBSERVATION PERIOD (JJAS 2004) • Conduct EOP for a period of 4 summer months (JJAS) to coincide with the peak monsoon season and maximum diurnal variability. • Conduct Intensive Observing Period (IOP) of up to one month (mid-July to mid-August) within the EOP during which time all networks are operational.
RAINGAUGE NETWORK Shuttleworth, Watts, Garatuza-Payan, Gochis (2001) • 90 new event logging gauges, indicated by red and blue dots, in SW-NE transects to sample gradients in rainfall from the GOC to the SMO.
NAME RAINGAUGE NETWORK DESIGN(OBJECTIVES) • To improve estimates of the diurnal cycle and topographic variation of precipitation in the core region of the NAM. • To facilitate hydrologically relevant diagnostic studies, including • intensity-duration-frequency analyses • rainfall accumulation spatial structure • spatial structure of mean rainfall • To facilitate modeling studies that use the new data to investigate, validate and improve the parameterization of precipitation processes in models.
DIURNAL VARIABILITY (1) The amplitude of the diurnal cycle in the core monsoon region is larger than the amplitude of the annual cycle. (2) There are large-scale shifts in the regions of deep convection during the day from over land to over water. (3) There is large intraseasonal and interannual variability of the diurnal cycle, but it is not well understood. (4) Improved monitoring and modeling of the diurnal cycle will go a long way towards improved warm season precipitation forecasts not just for Tier 1, but for Tiers 2 and 3.
NAME SIMPLE RAINGAUGE NETWORK Current site in CPC real-time daily Precipitation analysis Transects of simple raingauges Approximate regions for network enhancements Lobato et al. (2002) • NW-SE transects are needed to help resolve Gulf surge / precipitation relationships
CURRENT SOUNDING NETWORK SMN Contribution to NAME • Operate all once-daily observation sites at 12 UTC (2003-04) • Operate twice-daily observations (May-Nov) in 8 sites (2003-04) • Add 2 sites (Altamira and Tapachula) (2003) • Maintenance of the upper-air sounding network (2003-04) • Observer training (2003-04)
NAME RADIOSONDE / PIBAL NETWORK Douglas et al. (2002)
MOISTURE BUDGET OF THE INTRA AMERICAS SEA Radiosonde NCDC Buoys PACS SONET Zhang et al 2001 • Estimates of the moisture budget of the IAS region are in progress using this network, which is routinely available (2x daily) during the NH warm season. • These estimates will be combined with new estimates over the core (and peripheral) monsoon regions (based on a new network of in situ soundings) to quantify the Q flux-precipitation relationship over the entire region (inc. U.S.).
PROPOSED RADAR-PROFILING-SOUNDING NETWORK Carbone et al. 2002
NAME RADAR-PROFILING-SOUNDING(OBJECTIVES) • To describe the daily evolution of “ordinary”convective rainfall over the SMO, the GOC coastal plain and the southern Gulf region. • To describe the principal mechanisms that force organized mesoscale rainfall systems within the diurnal cycle (organization to larger scales). • To clarify relationships between convection over the SMO and Q-flux from the GOC and the GOM. • To observe moisture surges and associated LLJ’s in the GOC in the broader regional context of tropical easterly waves and mid-latitude westerly trough passages. • To clarify relationships between GOC moisture surges and precipitation.
Proposed Use of the R/V Ronald H. Brown During NAME Steve Rutledge, Walt Petersen, and Rob Cifelli Department of Atmospheric Science, Colorado State University • Instruments • Radar (Scanning C-band Doppler; Vertically pointing Ka-band Doppler) • Rawinsonde • 915 MHz wind profiler • DIAL/Mini-MOPA LIDAR • Multi-spectral radiometers • Air-sea flux system • Meteorological observation (T,RH, P), rain gauges and ceilometer • Oceanographic measurements including SST, CTD and ADCP