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MIDDLE ATMOSPHERE RESEARCH. HIRDLS: The High Resolution Dynamics Limb Sounder Future potential in remote sensing for the UT/LS region. Benefit to the community UT/LS Research Initiative Building upon existing strength, anticipation of new capabilities (HIAPER)
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MIDDLE ATMOSPHERE RESEARCH • HIRDLS: The High Resolution Dynamics Limb Sounder • Future potential in remote sensing for the UT/LS region. • Benefit to the community • UT/LS Research Initiative • Building upon existing strength, anticipation of new capabilities (HIAPER) • opportunity for the greater role for university community. • WACCM: Whole Atmosphere Community Climate Model • An inter-Divisional Community modeling effort that benefits from a National Center setting.
Atmospheric Chemistry DivisionNational Center for Atmospheric Research 24-26 October 2001 NSF Review The High Resolution Dynamics Limb Sounder (HIRDLS) A Joint US-UK Experiment John Gille – US PI John Barnett – UK PI University of Colorado/NCAR Oxford University Objectives: Measure temperature, 10 species, aerosols and PSC’s from 8-80 km with SPECIAL EMPHASIS ON UT/LS. BETTER VERTICAL AND HORIZONTAL RESOLUTION THAN PREVIOUSLY AVAILABLE GLOBALLY. The High Resolution Dynamics Limb Sounder (HIRDLS) Experiment
HIRDLS Science Team U.S.U.K. Principal InvestigatorsJ. Gille, CU/NCAR J. Barnett, OXF Instrument Design, Management M. Coffey, NCAR C. Mutlow, RAL W. Mankin, NCAR J. Seeley, Reading J. Whitney, OXF Dynamical modeling and Analysis B. Boville, NCAR R. Harwood, Edinburgh J. Holton, UW D. Andrews, OXF C. Leovy, UW M. McIntyre, Cambridge H. Muller, Cranfield G. Vaughan, Aberystwith A. O’Neill, Reading Chemical Measurements & modeling L. Avallone, CU J. Pyle, Cambridge G. Brasseur, MPI Aerosol Science O. B. Toon, CU Radiative Transfer F. Taylor, OXF Data Handling, Retrieval, Gridding K. Stone, CU C. Rodgers, OXF E. Williamson, OXF The High Resolution Dynamics Limb Sounder (HIRDLS) Experiment
HIRDLS Science Objectives • Understand stratosphere-troposphere exchange of radiatively and chemically active constituents (inc. aerosols) down to small spatial scales • Understand chemical processing, transports and mixing in the upper troposphere/lowermost stratosphere/lower overworld • Understand budgets of quantities (momentum, energy, heat and potential vorticity) in the middle atmosphere that control stratosphere-troposphere exchange • Determine upper tropospheric composition (with high vertical resolution) • Provide data to improve and validate small scales in models • Measure global distributions of aerosols and PSC’s and interannual variations The High Resolution Dynamics Limb Sounder (HIRDLS) Experiment
Summary of Measurement Requirements Temperature <50 km 0.4 K precision 1 K absolute >50 km 1 K precision 2 K absolute Constituents O3, H2O, CH4, H2O, HNO3, NO2, N2O5, 1-5% precision ClONO2, CF2Cl2, CFCl3, Aerosol 5-10% absolute Geopotential height gradient 20 metres/500 km (vertical/horizontal) (Equivalent 60oN geostrophic wind) (3 m s-1) Coverage: Horizontal - global 90oS to 90oN (must include polar night) Vertical - upper troposphere to mesopause (8-80 km) Temporal - long-term, continuous (5 years unbroken) Resolution: Horizontal - profile spacing of 5o latitude x 5o longitude (approx 500 km) Vertical - 1-1.25 km Temporal - complete field in 12 hours } The High Resolution Dynamics Limb Sounder (HIRDLS) Experiment
Limb Technique and Coverage IR Limb Scanning Technique Infrared radiance emitted by the earth’s atmosphere, seen at the limb, is measured as a function of relative altitude. Technique previously applied by LIMS and ISAMS HIRDLS measures in 21 spectral channels. 12-hour coverage The High Resolution Dynamics Limb Sounder (HIRDLS) Experiment
Measurement Capabilities A L T I T U D E The High Resolution Dynamics Limb Sounder (HIRDLS) Experiment
HIRDLS Retrievals of 1 Orbit of Data Simulated from MOZART 3 Model The High Resolution Dynamics Limb Sounder (HIRDLS) Experiment
Future Plans • Oversee completion of Instrument Integration • Participate in EM calibration development • Participate in PFM testing and calibration • Oversee integration and testing on spacecraft and launch • Complete algorithms, include additional features • Finalize and test operational codes • Intensify planning for use of data in science studies • LAUNCH (Scheduled June 2003) • Process data, find and correct artifacts • Validate data • Apply data to studies, notably of the UT/LS The High Resolution Dynamics Limb Sounder (HIRDLS) Experiment
Atmospheric Chemistry DivisionNational Center for Atmospheric Research Upper Troposphere Lower Stratosphere (UT/LS) Sue Schauffler Associate Scientist IV Stratosphere/Troposphere Measurements Project 24-26 October 2001, NSF Review UT/LS
Importance of the UT/LS region • “The tropopause region exhibits a complex interplay between dynamics, transport, radiation, chemistry, and microphysics. This is particularly highlighted in the case of ozone and water vapor, which provide much of the climate sensitivity in this region.” (SPARC Tropopause Workshop, April, 2001). • Transition region between the troposphere and stratosphere, both of which have mechanisms of ozone production and loss that are fundamentally different. • Strong gradients in many trace constituents including water vapor and ozone. • Transport processes occur on a multitude of scales including global, synoptic, and subsynoptic. UT/LS
UT/LS ChemistryProduction and Destruction of Ozone • Seasonal variations in ozone and water vapor • HOx and NOx budgets • ClOx and BrOx budgets • PAN, organic nitrates, HNO3 contributions to NOy • Heterogeneous processes associated with aerosols and cirrus clouds • Aerosol formation and composition • Influence of the summer monsoon and convection on UT/LS chemistry UT/LS
Seasonal Variation in Water Vapor Randel et al., JGR, 106, 13, 14,313, 2001 Pan et al., JGR, 105, 21, 26,519, 2000 Figure 8. Horizontal structure of water vapor at 390K in July. Dark and light shading denote maxima (>4.6 ppmv) and minima (<3.6 ppmv) in water vapor, respectively. Plate 2. Comparisons of middle world water vapor from SAGE II, MLS, and ER-2 in-situ measurements for 350 K. UT/LS
UT/LS Annual Cycle in Ozone Logan: JGR, 104, 13, 16,115, 1999 An Analysis of Ozonesonde Data for the Troposphere Figure 8. Annual cycle at the tropopause (middle), 1 km below the tropopause (bottom) and 2 km above the tropopause (top) for four Canadian stations. Monthly median values are shown. UT/LS
TOPSE: NOy UT budget Frank Flocke: TOPSE NOy balance during TOPSE, north of 58 degrees, upper troposphere (>6km flight altitude) A. Weinheimer, NCAR B.A. Ridley, NCAR B. Talbot, UNH J. Dibb, UNH D. Blake, UC Irvine R. Cohen, UC Berkeley UT/LS
UT/LS Transport • Processes that maintain sharp gradients in constituents across the tropopause. • Influence of various transport processes, such as convection, on gradients of VOCs, halogens, nitrogen compounds, and other constituents. • Magnitude of irreversible exchange from transient baroclinic waves and large/small scale transport in midlatitudes. UT/LS
Tropopause Folding Event Tropopause fold observed during TOPSE: Browell et al., NASA Langley. J. Atmos. Sci., 37, 994, 1980 Shapiro, M.A. J. Beuermann, et al., 2001, Julich. PV (PVU) Potential Temp. (K) UT/LS
Evidence of Convective Transport: E. Atlas (NCAR), H. Selkirk (NASA) WB-57 Flight Convection Figure 1. Back-trajectories calculated along the WB-57 flight track intersect regions of strong convection in the tropical Pacific Ocean. Figure 2. CO – Methyl nitrate relationship observed during ACCENT (23 April) over the Gulf of Mexico (blue dots), and same relationship from PEM TROPICS (over tropical Pacific Ocean (red dots). The measurements and modeling of the Gulf data suggest convective redistribution over the Pacific followed by 2 day transport to the east. UT/LS
NCAR Aircraft Current: NSF/NCAR C-130 up to 7-8 km Future: NSF/NCAR HIAPER up to 14-15 km UT/LS
Tropopause Location Holton et al., Reviews of Geophysics, 33, 4, 403, 1995 (figure courtesy of C. Appenzeller) UT/LS
Tools in ACD for UT/LS Studies • Aircraft Instruments: Apel - Oxygenated hydrocarbons; Atlas - Halocarbons, Hydrocarbons, Alkyl nitrates, Oxygenated hydrocarbons; Cantrell – RO2; Coffey/Mankin – N2O, CO, FTIR; Eisele – OH, HNO3, Sulfur species; Fried – Formaldehyde; Ridley – NOx, NOy, Fast O3; Shetter – SAFS; Flocke/Weinheimer – PAN, PPN, MPAN, PiBN, APAN; Guenther – VOCs; Campos/ATD CO2, O3, CO, H2O, and aerosol instruments. • Models: Garcia/ Kinnison – WACCM/MOZART; Madronich – MM, TUV; McKenna – CLaMS; Hess - HANK • Satellite observations and analysis: Gille – HIRDLS, MOPITT; Randel – HALOE, TOMS; Massie - UARS • Ground based remote sensing: Mankin/Coffey – FTIR spectrometer; Newchurch - RAPCD UT/LS
UT/LS Field Campaign • Initial field campaign to study Photochemistry at mid to high latitudes out of Jeffco using HIAPER. To formulate details of the field campaign, ACD will convene a community workshop to solicit ideas and input from colleagues at universities and other government sponsored agencies. • Integrate aircraft measurements, satellite observations, and modeling efforts. • Use simultaneous observations of key active and tracer species as constraints for testing and improving atmospheric models. UT/LS
Atmospheric Chemistry DivisionNational Center for Atmospheric Research WACCM: Whole Atmosphere Community Climate Model Rolando Garcia Senior Scientist, Modeling Group (special thanks to D. Kinnison) NSF Review, 24-26 October 2001 WACCM: Whole Atmosphere Community Climate Model
WACCM MotivationRoble, Geophysical Monographs, 123, 53, 2000 • Coupling between atmospheric layers: • Waves transport energy and momentum from the lower atmosphere to drive the QBO, SAO, sudden warmings, mean meridional circulation • Solar inputs, e.g., auroral production of NO in the mesosphere and downward transport to the stratosphere • Stratosphere-troposphere exchange • Climate Variability and Climate Change: • What is the impact of the stratosphere on tropospheric variability, e.g., the Artic oscillation or “annular mode”? • How important is coupling among radiation, chemistry, and circulation? (e.g., in the response to O3 depletion or CO2 increase) Jarvis, “Bridging the Atmospheric Divide” Science, 293, 2218, 2001 WACCM: Whole Atmosphere Community Climate Model
WACCM Motivation • Response to Solar Variability: • Recent satellite observations have shown that solar cycle variation is: • 0.1% for total Solar Irradiance • 5-10% at 200nm • - Radiation at wavelengths near 200 nm is absorbed in the stratosphere • => Impacts on global climate may be mediated by stratospheric chemistry and dynamics • • Satellite observations: • There are several satellite programs that can benefit from a comprehensive model to help interpret observations • e.g., UARS, TIMED, EOS Aura UARS / SOLSTICE WACCM: Whole Atmosphere Community Climate Model
Chronology of Model Development • 1999: Scientists in ACD, CGD, HAO agree on the need for a comprehensive ground-to-thermosphere model • 1999-2001: NCARDirector’s fund provides “seed money”to support 1.3 new FTE’s. Allows software development and “proof of concept” • 2001: Initial work on model completed (chemistry calculations are currently “offline”) • 2001: Preliminary scientific results presented at the CCSM Workshop in Breckenridge, CO, and at the IAMAS Assembly in Innsbruck, Austria • 2001: Responsibility for support of 1.5 new FTEs transferred to the scientific divisions. Leveraged by proposals to NASA (LWS, ROSS Theory and Modeling) • 2002: WACCM workshop in connection with CEDAR meeting; model released to community
WACCM ComponentsCollaboration between 3 NCAR Divisions TIME GCM HAO R. Roble B. Foster ACD R. Garcia D. Kinnison S. Walters Mesospheric + Thermospheric Processes MOZART + WACCM Chemistry (currently offline) Dynamics + Physical processes plus additonal collaborators from all three divisions MACCM3 CGD B. Boville F. Sassi (Middle Atmosphere CCM)
WACCM and the NCARCommunity Climate System Model ICE + Atmosphere OCEAN WACCM LAND dynamics, chemistry WACCM uses the software framework of the NCAR CCSM. May be run in place of the standard CAM (Community Atmospheric Model) WACCM: Whole Atmosphere Community Climate Model
Dynamics Module Additions to the original MACCM3 code: • A parameterization of non-LTE IR (15 m band of CO2 above 70 km) merged with CCSM IR parameterization (below 70 km) • Short wave heating rates (above 70 km) due to absorption of radiation shortward of 200 nm and chemical potential heating • Gravity Wave parameterization extended upward, includes dissipation by molecular viscosity • Effects of dissipation of momentum and heat by molecular viscosity (dominant above 100 km) • Diffusive separation of atmospheric constituents above about 90 km • Simplified parameterization of ion drag WACCM: Whole Atmosphere Community Climate Model
WACCMZonal Winds, Temperature Gross diagnostics (zonal mean behavior) Complete climatological analysis is planned WACCM: Whole Atmosphere Community Climate Model
Solstice Temperature Distribution (K) July January note cold Antarctic winter stratosphere WACCM: Whole Atmosphere Community Climate Model
Chemistry Module(50 species; 41 Photolysis, 93 Gas Phase, 17 Heterogeneous Rx) • Our goal was to represent the chemical processes considered important in the: • Troposphere, Stratosphere, and Mesosphere: • Ox, HOx, NOx, ClOx, and BrOx • Heterogeneous processes on sulfate, nitric acid hydrates, and water-ice aerosols • Thermosphere (limited): • Auroral NOx production • Currently do not include ion-molecule reactions (Taken from Brasseur and Solomon, 1986) WACCM: Whole Atmosphere Community Climate Model
WACCM Chemical Species • Long-lived Species: (17-species, 1-constant) • Misc: CO2, CO, CH4, H2O, N2O, H2, O2 • CFCs: CCl4, CFC-11, CFC-12, CFC-113 • HCFCs: HCFC-22 • Chlorocarbons: CH3Cl, CH3CCl3, • Bromocarbons: CH3Br • Halons: H-1211, H-1301 • Constant Species: N2 • Short-lived Species:(32-species) • OX: O3, O, O(1D) • NOX: N, N(2D), NO, NO2, NO3, N2O5, HNO3, HO2NO2 • ClOX: Cl, ClO, Cl2O2, OClO, HOCl, HCl, ClONO2, Cl2 • BrOX: Br, BrO, HOBr, HBr, BrCl, BrONO2 • HOX: H, OH, HO2, H2O2 • HC Species: CH2O, CH3O2, CH3OOH WACCM: Whole Atmosphere Community Climate Model
Heterogeneous Chemistry Module Sulfate Aerosols (H2O, H2SO4) - LBS Rlbs = 0.1 mm k=1/4*V*SAD* (SAD from SAGEII) >200 K Sulfate Aerosols (H2O, HNO3, H2SO4) - STS Rsts = 0.5 mm Thermo. Model (Tabazadeh) ? Nitric Acid Hydrate (H2O, HNO3) – NAD, NAT RNAH= 2-5 mm Rlbs = 0.1 mm 188 K (Tsat) ICE (H2O, with NAH Coating) Rice= 20-100 mm 185 K (Tnuc) WACCM: Whole Atmosphere Community Climate Model
Computational Demands • Using the MOZART3 framework: • Resolution of 2.8 x 2.8 degrees horizontal, ~2 km vertical • Calculations at >500,000 grid cells; time step of 20 minutes • Coded to run on massively parallel architectures (IBM Blackforest at NCAR) • 16 nodes x 4 processors per node (64 processors) • 1 model year = 1.25 wall clock days • Near Future… Advanced Research Computing System (ARCS) • Expect a 5-fold increase in computational resources • 4 model years = 1 wall clock day WACCM: Whole Atmosphere Community Climate Model
CH4 (ppmv), March UARS / HALOE+CLAES Data WACCM / MOZART3 WACCM: Whole Atmosphere Community Climate Model
NOx (ppbv), March UARS / HALOE Data WACCM / MOZART3 WACCM: Whole Atmosphere Community Climate Model
Total Column Ozone (Dobson Units) WACCM (daily) Earth Probe TOMS, 1999 (daily) WACCM: Whole Atmosphere Community Climate Model
Equatorial H2O (ppmv), UARS HALOE Strat / Trop Exchange of Water Vapor: A Key Question for Chemistry and Radiative Transfer The observed “tape recorder” signal in the lower stratosphere is shown at left (imprint of the sesonal cycle in tropopause temperature) WACCM: Whole Atmosphere Community Climate Model
Calculated Equatorial H2O (ppmv) Semi Lagrangian advection Lin and Rood advection (now used in WACCM) WACCM: Whole Atmosphere Community Climate Model
WACCM Science Application • Middle Atmosphere Variability due to Planetary Waves Propagating from the Troposphere: • Changes in tropical sea surface temperature (SST) alter the forcing of large-scale waves that propagate into the middle atmosphere • This can impact the structure and intensity of the winter polar night vortex • Model Simulation: • WACCM was run with time-dependentSSTfrom 1979 through 1998specified fromobservations • Model results grouped according to whether the SST distribution corresponds to El Niño or La Niña years WACCM: Whole Atmosphere Community Climate Model
Response in the Troposphere 500 mb Geopotential (JAN) Ensemble Difference El Niño – La Niña “canonical” tropospheric response (PNA pattern) WACCM: Whole Atmosphere Community Climate Model
Response in the Lower Stratosphere JAN DT (K) at 100 mb: El Niño – La Niña • ENSO effects extend into the stratosphere (and above) • At high latitudes, a large warm anomaly is shown which corresponds to a more disturbed polar vortex during El Niño years relative to La Niña years • A disturbed polar vortex is accompanied by polar temperatures colder by several degrees. • Could have significant impact on polar heterogeneous processes WACCM: Whole Atmosphere Community Climate Model
Future Work and Plans Interactive Dynamics and Chemistry Current (Offline Chemistry) Under development (Coupled Chemistry) Dynamics -------------------------------- Chemistry Dynamics -------------------------------- Chemistry Specified O3 drives Qsw Calculated O3 drives Qsw –> Coupled model allows feedbacks between Qsw and dynamics • Coming Attractions... • Community workshop will be organized for 2002 • WACCM to be released as community model WACCM: Whole Atmosphere Community Climate Model