ARC-IONS Workshop, U of T – 7-8/01/ ARC-IONS - First results from a North American Strategic Network David W. Tarasick Experimental Studies, Air Quality Research Division A.M. Thompson (PSU), S.J. Oltmans (NOAA), G. Forbes (EC-MSC), J. Merrill (UNH) NASA Aura Validation (M.J. Kurylo; K.W. Jucks); ARCTAS (J. Crawford) J. Davies, R. Mittermeier, W. Hocking, J. Witte G. Liu, C. Sioris, H. He, M.K. Osman, T. Carey-Smith L.B.J. McArthur, C. Banic & K. Puckett (EC); The Green Horse Society, and most especially all the many observers who obtained the ozonesonde measurements at the ARC-IONS sites.

ARC-IONS Workshop, U of T – 7-8/01/ Rationale Ozone soundings are the major source of information on ozone amounts in the free troposphere, capable of precise (3-5%) measurements of ozone with ~100m vertical resolution. While regular network soundings (typically weekly) produce valuable data, such soundings are often too sparse, both in space and time, to answer some scientific questions. Strategic networks are designed to answer specific scientific questions, typically with dense networks of daily launches that have sufficient resolution in space and time to resolve atmospheric dynamic variability. Launches can be coordinated, often with collocated aircraft or satellite measurements.

ARC-IONS Workshop, U of T – 7-8/01/ ARC-IONS Sites Largest ozonesonde intensive ever in Canada 13 sites in Canada 5 in US 1 in Greenland

ARC-IONS Workshop, U of T – 7-8/01/ TES / ARCIONS comparison. Summary of stare results for Bratt’s Lake, April 18 th, Cloud is optically thin. Sonde results show % bias at Barrow and 15% bias at Bratt’s Lake. 15% bias is consistent with lidar results.

ARC-IONS Workshop, U of T – 7-8/01/ Walsingham windprofiler radar

ARC-IONS Workshop, U of T – 7-8/01/ Double tropopause An example of a double tropopause observed at Churchill on April 18th, This event is due to a large poleward intrusion of subtropical tropospheric air and was forecast by the START08 project at NCAR (L. Pan, personal communication).

ARC-IONS Workshop, U of T – 7-8/01/ Arctic Intensive Ozonesonde Network Study (ARC-IONS) 2008 Cooperation with NASA project Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS), in April and July 2008 over northern Canada. Objectives: studies of boundary layer ozone depletions resulting from halogens released from sea salt deposited on Arctic sea ice; evaluation of the role of stratosphere/troposphere exchange (STE) in the spring buildup of tropospheric ozone; the contribution to the tropospheric ozone budget from boreal forest fires and the extent of fire emission influence on a trans-continental scale and beyond; validation of Aura (TES, OMI) at high latitudes; of GEM- MACH, for ozone & STE, and forest fire models.

ARC-IONS Workshop, U of T – 7-8/01/ Arctic Surface Ozone Depletions Arctic sites showed modest ozone depletion in the surface boundary layer throughout the spring campaign

ARC-IONS Workshop, U of T – 7-8/01/ This was occasionally severe. Arctic Surface Ozone Depletions

ARC-IONS Workshop, U of T – 7-8/01/ Tarasick and Bottenheim, ACP, 2, 197–205, 2002.

ARC-IONS Workshop, U of T – 7-8/01/ Sea ice? Temperature trends?

ARC-IONS Workshop, U of T – 7-8/01/ Backtrajectories for the sonde launches of April 17 th, These appear to correlate with the large amounts of BrO observed by the OMI instrument on April 16th, However, in other examples this relationship is less clear.

ARC-IONS Workshop, U of T – 7-8/01/ Do O 3 depletions correlate with satellite BrO?

ARC-IONS Workshop, U of T – 7-8/01/ Do O 3 depletions correlate with satellite BrO?

ARC-IONS Workshop, U of T – 7-8/01/ Do O 3 depletions correlate with satellite BrO?

ARC-IONS Workshop, U of T – 7-8/01/ Do O 3 depletions correlate with satellite BrO?

ARC-IONS Workshop, U of T – 7-8/01/ Ozone from the stratosphere? M.K. Osman, UWO

ARC-IONS Workshop, U of T – 7-8/01/ FLEXPART modeling seems to show good correspondence with apparent intrusions T. Carey-Smith, NIWA Intrusions associated with jumps in tropopause height

ARC-IONS Workshop, U of T – 7-8/01/ TES Measurements: Eureka H. He, UWO/ARQX

ARC-IONS Workshop, U of T – 7-8/01/ Radar tropopause height vs Brewer ozone H. He, UWO/ARQX

ARC-IONS Workshop, U of T – 7-8/01/ T. Carey-Smith NIWA

ARC-IONS Workshop, U of T – 7-8/01/ Ozonesonde Climatology G. Liu, ARQX Hysplit forward and back- trajectories applied to ozone soundings fill in the NA map

ARC-IONS Workshop, U of T – 7-8/01/ Ozonesonde Climatology G. Liu, ARQX +- 3 hrs, Mar-May, hrs, Aug 2006 Correlations between OMI and trajectory-mapped ozone soundings at different altitudes

ARC-IONS Workshop, U of T – 7-8/01/ Ozonesonde Climatology G. Liu, ARQX

ARC-IONS Workshop, U of T – 7-8/01/ Ozonesonde Climatology G. Liu, ARQX

ARC-IONS Workshop, U of T – 7-8/01/ ARCTAS Data Workshop, January 27-30, Virginia Beach Spring AGU Meeting May, 2009 (Toronto) Session A10: Processes over Midlatitude North America and the Arctic (2008) Observed from Satellite and Field Campaigns Abstract deadline: 4 March 2009, 2359 UT. MST12 (Radar) Workshop: May, 2009 London, Ontario: Session: Tropopause processes and Stratospheric/Tropospheric Exchange Abstract deadline: Friday January 23,

ARC-IONS Workshop, U of T – 7-8/01/ Thank you!

ARC-IONS Workshop, U of T – 7-8/01/ Highlights of three IONS campaigns: IONS-04: 2004, mostly eastern North America; 275 profiles, largest single set of free tropospheric ozone measurements ever compiled (as of 2004) for this region. Coordinated AQ model comparison, aircraft & surface measurements. IONS-06: 2006, three phases with 23 sites; 740 profiles. Coordinated AQ model comparison, aircraft & surface measurements. Validation of TES, OMI, MLS, ACE measurements; coordination with Aura & ACE overpasses. ARC-IONS (2008): Canada, Alaska and the lower U.S.. Two phases with 18 sites, mostly daily profiles. Coordination with NASA aircraft flights. Validation of TES, OMI, MLS, ACE measurements; coordination with Aura & ACE overpasses. Coordination with special TES “Step-and-stare” observations. Also new tropospheric ozone lidars in operation at Egbert (Toronto) and Eureka; aerosol optical depth (AOD) measurements from the Canadian AERONet and Brewer networks, and an aerosol lidar deployed near Yellowknife. Radar measurements of tropopause height to detect stratospheric intrusions, and to measure wave activity and turbulence strengths associated with intrusion events. Modeling studies using GEM-MACH, GEM-FLEXPART and other systems, in order both to validate the models and to interpret the data.

ARC-IONS Workshop, U of T – 7-8/01/ H. He, UWO/ARQX

ARC-IONS Workshop, U of T – 7-8/01/ M.K. Osman, UWO

ARC-IONS Workshop, U of T – 7-8/01/ Ozonesonde Climatology G. Liu, ARQX

ARC-IONS Workshop, U of T – 7-8/01/ IONS Publications (>24 to date): Unique data sets provided by coordinated intensive ozone profile measurements tropospheric ozone processes & contribution to ozone budget; model comparisons (Cooper et al., 2006; 2007; Thompson et al., 2007a,b; Tarasick et al., 2007; Pfister et al., 2008; Tang et al., 2008) pollution plumes from boreal forest fires (Morris et al., 2006), New York City (Mao et al., 2006). stratospheric intrusions & the tropopause behaviour preceeding them (Hocking et al., 2007). validation of satellite measurements (Parrington et al., 2007; Stajner et al., 2007; Schoeberl et al., 2007; Nassar et al., 2007; Jiang et al., 2007; Dupuy et al., 2007; Livingston et al., 2007; Nardi et al., 2007) and of models (Chai et al., 2007; Pierce et al., 2007; Yu et al., 2007).

ARC-IONS Workshop, U of T – 7-8/01/ Sea ice? Temperature trends?

ARC-IONS Workshop, U of T – 7-8/01/ Ozonesonde Climatology G. Liu, ARQX

ARC-IONS Workshop, U of T – 7-8/01/ EC Regional AQ models AURAMS & CHRONOS compared with IONS-04 sonde data forecast errors 25-75% low bias in upper troposphere GEM-MACH: global, full stratosphere

ARC-IONS Workshop, U of T – 7-8/01/ Comparison of GEOS-Chem with Ozonesonde Data Assimilation improves the O 3 distribution in the UTLS region O 3 plume is redistributed throughout column in assimilation Sonde Assimilation GEOS-Chem Ozone (ppb) Eureka (85°W, 80°N) 20 July 2005 Churchill (95°W, 58°N) 20 July 2005 Wallops (76°W, 38°N) 26 July 2005 Wallops (76°W, 38°N) 19 July 2005 Pressure (hPa)

ARC-IONS Workshop, U of T – 7-8/01/ Stratosphere-Troposphere Exchange Stratospheric intrusion at 40ºN more pronounced in both models following assimilation AM2-Chem ozone (120°W 21:00 GMT, July 26) AM2-Chem ozone analysis GEOS-Chem ozone (120°W 21:00 GMT, July 26)GEOS-Chem ozone analysis

ARC-IONS Workshop, U of T – 7-8/01/ Tropospheric Ozone DIAL - First Results ARC-IONS Campaign Generated a DIAL ozone profile for full day and 2 hours centred at ozonesonde launch time Generally not much difference between full and coincident profiles DIAL shows similar features to ozonesonde profile, does not show an increase in ozone concentration with altitude

ARC-IONS Workshop, U of T – 7-8/01/ H. He, UWO/ARQX