NRT Tropospheric and UTLS Ozone NRT Tropospheric and UTLS Ozone From OMI/MLSFrom OMI/MLS

NRT Tropospheric and UTLS Ozone NRT Tropospheric and UTLS Ozone From OMI/MLSFrom OMI/MLS

Mark A. OlsenMark A. OlsenUMBC/GESTUMBC/GEST

(At NASA/GSFC)(At NASA/GSFC)

olsen@code613-3.gsfc.nasa.govolsen@code613-3.gsfc.nasa.gov

Mark SchoeberlMark SchoeberlNASA/GSFCNASA/GSFC

Mark A. OlsenMark A. OlsenUMBC/GESTUMBC/GEST

(At NASA/GSFC)(At NASA/GSFC)

olsen@code613-3.gsfc.nasa.govolsen@code613-3.gsfc.nasa.gov

Mark SchoeberlMark SchoeberlNASA/GSFCNASA/GSFC

START08 WorkshopJanuary 9, 2008

MLS and OMI Ozone DataMLS and OMI Ozone DataMLS and OMI Ozone DataMLS and OMI Ozone Data

MLS Stratospheric O3 Column Map made from MLS measurement points shown

Data between tracks is interpolated. Assumes no structure between tracks.

Both MLS and OMI are on the Aura platform providing concurrent stratospheric ozone (MLS) and total column ozone (OMI) measurements.

Level 2 (along-track) MLS data reported at 316, 215, 147, 100 hPa and higher.

Tropospheric column ozone given by OMI column - MLS column as by Ziemke et al. [2006].

Both provide daily global coverage (14 orbits) but longitudinal resolution of MLS is ~25° compared to ~0.25° for OMI.

High Resolution Stratospheric Ozone MapsHigh Resolution Stratospheric Ozone MapsHigh Resolution Stratospheric Ozone MapsHigh Resolution Stratospheric Ozone Maps

High-resolution (1° x 1.25°) stratospheric ozone maps from MLS used with OMI column data to produce tropospheric ozone residual (TOR).

To increase the effective resolution of the MLS data, forward trajectories mapped from the previous 6 days on to the orbit track. Theoretical Improvement: 6 days of trajectory mapping gives ~ 2-3° horizontal resolution.

To increase the effective resolution of the MLS data, forward trajectories mapped from the previous 6 days on to the orbit track. Theoretical Improvement: 6 days of trajectory mapping gives ~ 2-3° horizontal resolution.

Comparison to Ziemke et al. Low Resolution TORComparison to Ziemke et al. Low Resolution TOR

June Trop. Column Ozone June Ziemke et al. [2006]

Monthly Mean

Differences between this product and Ziemke’s TOR.1) High resolution stratospheric column2) Tropopause height is computed using PV in the extra

tropics.

Even with monthly average, much more structure is seen using the high-res stratospheric column ozone.

Case ComparisonCase Comparison6 day average

Ziemke et al. 2006

800 ppbv

Air pollution transport?

Mean tropospheric ozone mixing ratio used to eliminate topographic effects. This day shows a high ozone region off the U. S. east coast. The fold identification scheme (white) shows that this feature appears to be due to a stratospheric ozone fold, not pollution. Daily ozone mean mixing ratios are usually high - much higher than the 6 day average.

Improved Time SynchronizationImproved Time SynchronizationImproved Time SynchronizationImproved Time Synchronization

In the previous example the all data is assumed to asynoptic - measurement times are ignored. This can create problems with rapid moving events like folds.

Synoptic TOR• Use OMI L2G with measurement time stamp• Forward trajectories are grouped in time for target day (1/10th

day resolution)• Tropopause is time interpolated from 6 hour DAS fields-----------• Product has same zonal mean as asynoptic TOR• Fold TOR anomalies are greatly reduced

In the previous example the all data is assumed to asynoptic - measurement times are ignored. This can create problems with rapid moving events like folds.

Synoptic TOR• Use OMI L2G with measurement time stamp• Forward trajectories are grouped in time for target day (1/10th

day resolution)• Tropopause is time interpolated from 6 hour DAS fields-----------• Product has same zonal mean as asynoptic TOR• Fold TOR anomalies are greatly reduced

Time Synchronized ProductTime Synchronized ProductTime Synchronized ProductTime Synchronized Product

Time SynchronizedTime Synchronized

Tropospheric ColumnTropospheric Column

Not Time SynchronizedNot Time Synchronized

June 26, 2005June 26, 2005June 26, 2005June 26, 2005

MeanTroposphericMixing Ratio

TropopausePressureAnomaly

(From OMI column -Hi-Res Strat. Column)

Note: Only 150°E to 0°

June 26, 2005June 26, 2005June 26, 2005June 26, 2005

MeanTroposphericMixing Ratio

TropopausePressureAnomaly

(From OMI column -Hi-Res Strat. Column)

Note: Only 150°E to 0°

More Mean Trop. Ozone and STEMore Mean Trop. Ozone and STEMore Mean Trop. Ozone and STEMore Mean Trop. Ozone and STE

June 28, 2005

July 1, 2005

Mean tropospheric ozone maxima tend to occur near locations of significant ozone STE.

However, not all STE maxima are associated with distinct maxima in the tropospheric ozone field. (Meteorology? Other???)

PV-Theta MappingPV-Theta MappingPV-Theta MappingPV-Theta Mapping

Currently assessing new product that uses stratospheric ozone mapped to PV and theta in the extratropics rather than trajectory mapping. (Trajectory mapping still used in tropics).

• PV and theta mapping from DAS and MLS ozone near target day

• Evaluation of this product with sondes and comparisons to trajectory mapping only is currently incomplete.

Currently assessing new product that uses stratospheric ozone mapped to PV and theta in the extratropics rather than trajectory mapping. (Trajectory mapping still used in tropics).

• PV and theta mapping from DAS and MLS ozone near target day

• Evaluation of this product with sondes and comparisons to trajectory mapping only is currently incomplete.

PV-Theta ProductPV-Theta ProductPV-Theta ProductPV-Theta Product

Mean Tropospheric Mixing RatioMean Tropospheric Mixing Ratio

In NH, overall structure is similar although small differences exist.

Gradients near fronts appear to be more well-defined.

Greatest differences seen in SH.

ComparisonsComparisonsComparisonsComparisons215 hPa ozone; June 30, 2005215 hPa ozone; June 30, 2005

PV-theta is used when LMS depth exceeds 1.8 km

SimpleInterpolation

Tropics are “flat”

SH notso good!

NRT CapabilityNRT Capability

MLS team plans to start producing NRT ozone for testing and interface purposes in Jan 08.

Online production stream in NRT in Feb 08.

How “Near to Real Time” is still uncertain. High resolution stratospheric ozone maps: less than 3 hours after availability of MLS data.

Currently checking availability of NRT OMI ozone data to produce high resolution tropospheric ozone in the same timeframe.

Products OverviewProducts Overview High resolution (1° x 1.25°) stratospheric ozone from MLS with trajectories.

Two levels below HIAPER ceiling (215 and 147 hPa).

Likely available with no more than two days lag (hopefully not more than one).

Tropospheric ozone column and mean mixing ratio at same resolution. Time frame dependant on OMI data availability.

Possibility of advecting stratospheric ozone field as passive tracer in model for forecasting purposes?

Best case scenario: Both mean tropospheric ozone and UTLS ozone can be used for forecasting/flight planning.

Worst case scenario: these can be used in post-flight analysis.