Michael J. Newchurch 1, Guanyu Huang 1, John Burris 2, Shi Kuang 1, Wesley Cantrell 1, Lihua Wang 1, Patrick I. Buckley 1, Brad Pierce 3

Transcription

1 Complementary Ground-based and Space-borne Profile Measurements for Air Quality presented at 1 st Workshop Satellite and Above-boundary-layer Observations for Air-Quality Management 9-10 May, 2011 Boulder, CO Michael J. Newchurch 1, Guanyu Huang 1, John Burris 2, Shi Kuang 1, Wesley Cantrell 1, Lihua Wang 1, Patrick I. Buckley 1, Brad Pierce 3 1 Atmospheric Science Department, University of Alabama in Huntsville 2 Goddard Space Flight Center, NASA 3 University of Wisconsin

2 Outline 1. Satellite kernels 2. The effect of initial and boundary conditions 3. Sondes and lidars and laminar structures 4. Birmingham ozone/aerosol plume 5. STE of ozone 6. Ozone lamina climatology 7. Modeling of laminar structures

3 Introduction Satellite observations of trace gases have progressed significantly in the last decade from total ozone column measurements by TOMS to ozone profiles by OMI and NO2, HCHO, CHOCHO by OMI, Gome, and SCIMACHY. Balloon borne ozone soundings at weekly intervals are now complemented by ground-based ozone DIAL measurements at sub-hourly intervals. Several intensive campaigns integrating space-borne, air-borne, balloon-borne, and ground-based in-situ campaigns and remote sensing techniques have significantly enhanced our understanding of the chemistry and physics controlling surface ozone and aerosol amounts. The next level of understand will derive from diagnosing the processes involved in forming and transporting the ubiquitous tropospheric layers we observe in the boundary layer and in the free troposphere. These tropospheric ozone layers have significant potential implications for a variety of dynamic, chemical atmospheric processes and energy budgets (Newell et. al,. 2001). However, we have little understanding of the mechanisms controlling ozone layers and the models don t reproduce the laminae very well. (Zhang and Rao, 1999, Stoller et al., 1999, Newell et al., 2001, Thouret et al., 2001, Colette et al., 2005a and 2005b,). We present the climatology of ozone laminar structure and its applications to models, satellite retrievals, and ground-level ozone amounts.

4 Courtesy of Owen Cooper/CU, ESRL

5 IR and UV Averaging Kernels

6 High-resolution PBL lidar observation suggests both UV and Vis radiances required to capture significant PBL signal for satellite Huntsville lidar observation on Aug. 4, 2010 Lidar obs. convolved with OMI UV averaging kernel---- unable to capture the highly variable ozone structure in PBL Lidar obs. Convolved with OMI UV-Vis averaging kernel- ---Captures the PBL ozone structure. X. Liu et al.

7 Theoretical retrievals from multi-spectral measurements Courtesy of Natraj, Liu, et al. True A priori UV retrieval Vis retrieval TIR retrieval UV + Vis UV + TIR UV + Vis + TIR

8 Ozone boundary conditions for CMAQ

9 HCHO boundary conditions for CMAQ

10 Lateral boundary transport is important

11 CMAQ/sonde at 5 sites. No boundary conditions

12 CMAQ/sonde at 5 sites. OMI Initial & boundary conditions

13 J O U R N A L O F A P P L I E D M E T E O R O L O G Y VOLUME 38 The Role of Vertical Mixing in the Temporal Evolution of Ground-Level Ozone Concentrations JIAN ZHANG AND S. TRIVIKRAMA RAO Department of Earth and Atmospheric Sciences, University at Albany, State University of New York, Albany, New York (Manuscript received 15 July 1998, in final form 19 February 1999) The results reveal that a greater reduction in the ground-level ozone concentration can be achieved by decreasing the concentrations of ozone and precursors aloft than can be achieved from a reduction of local emissions

14 Typical, large diurnal variability in the Boundary Layer Zhang and Rao, 1999

15 Laminar structure analyzed by CWT and the gradient method

16 Seasonal Variations Occur in Altitudinal Distributions- Layer Height WRT to Tropopause Height Gradient Wavelet Spring Low frequency of layers near tropopause Summer High frequency of layers below tropopause Trinidad Head 16

17 Fine structure in the temporal variations of layer attributes can be quantified by Wavelet and Gradient methods from Lidar observations. Layer A Max: 50.1 ppbv Mean Max-Min Min: 36.6 ppbv max-min : 2.5 ppbv / 10min +7.9 ppbv / 10min -2.4 ppbv / 10min A B Temporal variability from other layer attributes can be similarly quantified. For example: O3 peak altitude, mixing ratio at peak. Layer B Thickness Max: 4.8 km Mean Min: 3.0 km Thickness: 0.3 km /10min +0.9 km /10min -0.3 km /10min 17 17

18 Ozone in the free troposphere is not correlated with surface ozone Seasonal correlation of surface w/ ozone aloft Huntsville Ozonesonde Data P(R^2>0.5)= 10% 15% 19% 12%

19 Laminar structures cause anomalous behavior in correlations Huntsville Lidar Data EPA Surface Data

20 Correlation Lengths Definition: the altitude over which R^2 decreases from 1 to 0.5. Each line is a regression through the correlations of at least 0.5. Correlations >0.5 above the first occurrence of a statistically insignificant value (<0.5) are not considered. Two clusters Conclusion: Measurements of ozone above correlation length carries no info about surface ozone. Corollary: To determine surface ozone concentration, a measurement must contain info from within the correlation length.

21 Horizontal Variability 1/28/2011 UAHuntsville Campus Ozone Measured with ozonesonde Surface ozone of 24 sonde profiles compared with local EPA site: The variance in the surface ozone amounts at the ozonesonde/lidar site seen in the EPA HSV-Airport Rd. site (~10 km distant; Summer 2010) is about 75%. The other 25% is the HORIZONTAL variance. June 19 Inside ppbv Percent difference reaches ~30% for measurements away from buildings.

22 $800/ ozonesonde launch No more than 6 launch per 24 hours = 4-hour resolution $800/launch*6launch/day*365days/year=$1,752,000/year 22

23 sonde 4-hour temporal resolution vs. 10-minute resolution

24 Apr. 17 Apr. 23 What We Missed with the Weekly Ozonesonde Measurements? May 1 Apr. 27 Dry air Additional sonding on Tue. after the lidar detection of Stratosphere-troposphere exchange (STE) 24

25 Tropospheric ozone variability due to STE captured by the HSV lidar O3 lidar retrieval 500ppbv 10min resolution Cloud Cloud Cloud sonde

26 Different variation structures for ozone and aerosol suggest local photochemistry dominates the production Ozone mixing ratio, August 4, 2010 O3 diurnal variation The rapid aerosol variation in the PBL suggests the importance of a collocated aerosol measurement. Aerosol ext. coeff. at 291nm from O3 DIAL 26

27 Nocturnal ozone enhancement associated with low-level jet Lidar Oct. 4, 2008 Co-located wind profiler Low-level jet Aerosol ext.coeff. at 291nm from O3 lidar (a) Co-located ceilometer backscatter Positive correlation of ozone and aerosol due to transport Kuang et al. submitted to Atmospheric Environment Aerosol 27

28 RAQMS misses ozone layer at 2-4km over estimates depth of 6-8km layer May 3, 2010 Daytime PBL top collapsed shows collapse of PBL May 01 May 02 May 03 May 04 May 05 May 06 May 07 May 08

29 RAQMS shows diffuse free Tropospheric ozone May 7 Does not resolve thin filaments observed By lidar May 01 May 02 May 03 May 04 May 05 May 06 May 07 May 08 Saharan dust event O3 AQ event

30 Ozone Lidar Network 1. EPA/Las Vegas recognized value of ozone lidar in 1977 and began instrument research. 2. Technology developed to produce a/c instruments (Browell/NASA, Hardesty/NOAA) and ground-based (McDermid/NASA/TMF, Newchurch/UAH&NASA). A few other ozone lidars operate in Europe and Asia. 3. NASA has formed a working group to identify a pathway in science and technology to eventually create a network of ground-based ozone lidars. 4. Such an ozone lidar network would be very complementary to the NASA GEO-CAPE geostationary AQ/Ocean satellite planned for ~2020.

31 An example of NO2 lidar -RIVM mobile NO2 lidar in the Netherland S. Berkhoutet al., 2006 ILRC The mobile lidar system while measuring H. Volten et al JGR Interior of the mobile laboratory 31

32 Conclusions 1. Satellite observations of trace gases provide good spatial coverage with limited vertical resolution. These satellite obs are helpful for model ic/bc constraints. 2. Ozonesonde and lidar observations identify ubiquitous laminar structures. 3. Laminar transport from STE and NBL transport can be important for AQ. 4. Current regional models often do not resolve laminar structures of importance to surface AQ. 5. An ozone lidar network is a potential solution to acquire the vertical ozone information needed by AQ practitioners.

33 Formaldehyde/NO2 Ratio Duncan et al.

34 IONS ozonesonde network Thompson et al.

35 Continuous Wavelet Transform (CWT) The CWT coefficient is defined as: 1 zt z b W f ( a, b) = f ( z) Ψ( ) dz z a b a a is the spatial extent or dilation of the function. b is the location at which the wavelet function is centered the translation of the function. f(z) is the signal of interest, in this case, an ozone profile. Z t and Z bare the top and the bottom of the profile. Ψ(z) is the wavelet function.

36

37 IONS06 Sonde/EPA surface comparisons Correlating EPA surface ozone with the sonde measurements at 500m causes a 25% decrease in correlation. Using EPA surface data as the origin in the lidar case is not useful or accurate.

38 IONS06 Sonde/EPA surface comparisons The variance in the surface ozone amounts at the ozonesonde/lidar site seen in the EPA HSV- Airport Rd. site is about 75%. The other 25% is the HORIZONTAL variance.

39 Using difference quotients to find extreme points of ozone profiles Difference quotients are used to find extreme points of the mixing ratio. Local minima and maxima are filtered (max-min > 15%) to distinguish significant layers based on the threshold percent difference value. A 3-point boxcar average is applied to data before difference quotients are applied. Huntsville Ozonesonde Data

40 Same profiles as previous slide with correlation origin at 500m. (No EPA sfc data) Correlation improves when EPA data isn t used. Ozone at 500m is still very uncorrelated with aloft ozone

41 Correlations of EPA surface ozone with ozone aloft measured by Huntsville DIAL Time Period: May, Jul, Aug 88 hours of data ~ 500 profiles Ozone in FT is not correlated with surface. All correlations are in 2 hours intervals and then are averaged over the entire data set. Std Err of mean: Random Distribution

42 Timing of low upper tropospheric ozone minimum seems delayed (note RAQMS only every 6hrs) May 4, 2010 doesn t show surface O3 enhancement May 01 May 02 May 03 May 04 May 05 May 06 May 07 May 08

43 RAQMS is in good agreement with Huntsville Lidar above ~3km May 5 under estimates low level ozone enhancement May 01 May 02 May 03 May 04 May 05 May 06 May 07 May 08 O3 AQ event

44 RAQMS is in good agreement with Huntsville Lidar above ~3km May 6 (high PBL O3) under estimates low level ozone enhancement May 01 May 02 May 03 May 04 May 05 May 06 May 07 May 08 Saharan dust event O3 AQ event