# Presentation: 897614

## HIRDLS Validation Status

- _(v2.04.09)_
- B. Nardi, J. Gille & HIRDLS Team
- AURA, Science Meeting
- Pasadena, Oct 1-5, 2007

## Overview

- Temperature validation
- Ozone validation
- Nitric Acid validation
- Cloud counting/height validation
- Summary

## Temperature

## Temperature Lidar 

- _MLO_
- _[19.5__o__N, 156__o__W]_

- _TMF_
- _[34.5__o__N, 118__o__W]_

- _Temperature Lidar _
- _Profile Comparisons_

**Notes:**
Illustrate T Vertical Resolution and Accuracy

## Temperature Lidar comparisons – Statistical Differences

- _Temperature Lidar comparisons – Statistical Differences_

- _Mauna Loa Observatory [19.5__o__N, 156__o__W]_

- _Table Mountain Facility [34.5__o__N, 118__o__W]_

- Coincidence = 560 km, 12 hrs

**Notes:**
Illustrate T Vertical Resolution and Accuracy:   Consolidate with previous

## Mean Differences

- Mean difference, HIRDLS-COSMIC, for the Double COSMIC+HIRDLS coincidences. The solid line gives the difference, the outer dashed lines give the difference +/- the standard deviation of comparisons about the mean, and the inner dashed lines give the 1 standard deviation error bars of the mean.

**Mean Differences**

**Temperature comparison with COSMIC/GPS, **
**on small vertical distance scales.**

- _COINCIDENCE: Profiles were required to be within 0.75o great circle and 500 sec of each other_, giving 888 pairs.HIRDLS and COSMIC profiles were separately smoothed using a cosine bell filter of 2.8 km full width at half height (high pass filtered). The deviations from these profiles were then intercorrelated over the range 2.0 to 4.75 pressure scale height.

- J.J. Barnett

- The FORMOSAT-3/COSMIC constellation of six satellites,
- launched 14 April 2006, carries GPS receivers. Resolution = 1 km.

## Sonde Temperature Comparisons

**Individual Profiles**

- Gille et al, 2007

- _Sonde Temperature Comparisons_

**Statistical Differences**

- -2          2

- -2            2

- Pressure (hPa)

- Pressure (hPa)

- Temperature (K)

- Temperature (K)

- -2            2

- -2            2

**Notes:**
Illustrate T Accuracy ( & Vertical Resolution?)

## Temperature Comparison with ACE-FTS

- _Temperature Comparison with ACE-FTS_

- Average temperature differences (solid, HIRDLS-ACE) and standard deviation (dashed).

**Notes:**
T Accuracy at high latitudes

## Predicted: L2 retrieved parameter, f(radiance error, a priori error, Jacobians)

- Observed: Standard Deviation of differences at orbit-crossover.

- _Temperature: Estimated Precision_

- Empirically determined precision for HIRDLS determined from differences of paired profiles (dashed line) at latitude cross-over points at 80°N for 2 days in March and 2 days in September, compared total precision calculated by the retrieval code (solid line).   The total variation of the GMAO and HIRDLS data for those situations are also shown.

**Notes:**
T precision. Source of Observed precision ??? 

## Ozone

## OZONE Lidar 

- _MLO_
- _[19.5__o__N, 156__o__W]_

- _TMF_
- _[34.5__o__N, 118__o__W]_

- _OZONE Lidar _
- _Profile Comparisons_

**Notes:**
Illustrate T Vertical Resolution and Accuracy

## OZONESONDE Profile Comparisons

_**OZONESONDE Profile Comparisons**_

**Notes:**
Illustrate O3 Vertical Resolution

## OZONE Lidar comparisons – Statistical Differences

- _Mauna Loa Observatory [19.5__o__N, 156__o__W]_

- _Table Mountain Facility [34.5__o__N, 118__o__W]_

**Notes:**
Illustrate T Vertical Resolution and Accuracy:   Consolidate with previous

## OZONESONDE Comparisons – Statistical Differences

_**OZONESONDE Comparisons – Statistical Differences**_

**Notes:**
Illustrate O3 Accuracy

## Ozone: INTEX-B AROTAL Lidar

_**Ozone: INTEX-B AROTAL Lidar**_

## Ozone

- V. Lynn Harvey

- Anticyclone
- border

- HIRDLS
- v2.04.09

- MLS
- v2.2

- Polar Vortex
- border

_**Ozone**_

## Ozone Estimated Precision

- Cora Randall

_**Ozone Estimated Precision**_

- December

- June

- ~50 km, ~1 hPa --

- ~15 km, ~120hPa  --

## Nitric Acid

## HNO3: ACE-FTS comparisons

- Cora Randall

- NH

- SH

- ΔVMR

- %Difference

## Percent Difference [10o zonal mean]

_**MLS v2.2: Mean Percent Difference**_

- Cora Randall

- Solid = Mean difference
- Dashed = Std Dev of Difference

- ST23 only = current Scan Table
-                      (since May 2006)

- Over 278,000 coincidences within 1 latitude and 4 longitude. Theoretical precision criteria of 30% used.

## Airborne profile comparisons - Houston AVE [June 2005]

- Kinnison et al, 2007

- _Airborne profile comparisons - Houston AVE [June 2005]_

- HIRDLS (red)
- NOAA CIMS (blue)

- For this flight, HIRDLS HNO3 is broadly consistent with the NOAA CIMS instrument in the 100 hPa - 75 hPa region. Below this region, HNO3 filaments as measured by CIMS are not captured. The reason for this is currently not understood.

## HNO3 Estimated Precision

- December

- June

_**HNO3 Estimated Precision**_

- ~32 km, ~10 hPa -

- ~17 km, ~100hPa  -

## Clouds

## Detection of Sub-Visual Cirrus Layer (12 μm, channel #6)

_**Cirrus Layer Extinction Profile **_

- S. Massie

_**Tropical Cirrus Layer**_

**700 %**
**Radiance**
**Perturbation**

_**Detection of Sub-Visual Cirrus Layer (12 μm, channel #6)**_

**Notes:**
This observation corresponds to 13.6 S and 314.78 E on May 18, 2006, the same profile as in
the previous slide.

## Cloud Top Pressure Determinations

- S. Massie

**Compare the cloud counting capability of the HIRDLS with HALOE.**

## Cirrus Frequency of Occurrence

- S. Massie

- Derived from
- Multi-spectral
- Extinction (all clouds)

- Derived from
- Radiance-based
- cloud detection
- algorithm. (types 1,2)

- Longitude

- Latitude

- Latitude

**Notes:**
The HIRDLS geographical distribution of clouds are similar to those observed by the HALOE experiment.

Cloud types 1,2,and 4 are for the unknown cloud type, cirrus layer, and opaque cloud types.

The most appropriate comparison is between the HALOE values and the middle panel (cloud types 1 and 2),
since the HALOE experiment will not be able to retrieve extinction for the opaque cloud types.

## Seasonal Variations of Cirrus Layers

_**Seasonal Variations of Cirrus Layers**_

- S. Massie

_**CALIPSO**_

_**HIRDLS**_

**Winter**
**NH**

**Spring**
**NH**

**Summer**
**NH**

**Fall**
**NH**

**Notes:**
Note that the frequency of occurrence of cirrus layers is mapped here on a smaller range ( 0 – 18 )
than that of the previous slide for all clouds (0 – 90).

## Summary of quality of validation products

- Temperature:
- 	P-Range:	1-300 hPa
- 	Precision: 0.5K at 10-100 hPa;  1K @ 1 hPa (v2.02.07)
- 	Accuracy: ±2K at 1-100 hPa
- Ozone:
- 	Range: 	1-100+ hPa (mid-high Lat), 1-50 hPa (tropics)
- 	Precision: 5-10%
- 	Accuracy: 2-10% at 1-10 hPa; biased generally low
- 		5% high bias ~10-30 hPa
- 		0-20% low bias, ~30-100+ hPa (mid & high latitudes)
- Nitric Acid:
- 	Range: 	10-100 hPa, 10-50 hPa (tropics)
- 	Precision: 10-35% at 100-10hPa
- 	Accuracy: ~10% (at 10hPa) to 30% (at 100hPa); biased low [ACE-FTS]
- Clouds/Aerosol:
- 	Range: 	400 hPa- 10 hPa
- 	Correlation with other instruments:
- 		SAGE & HALOE (cloud-top pressure): 0.85 - .93
- 		CALIPSO horizontal cloud scale: 0.99
- 	Extinction retrieval successful at rate 70%: needs improvement
- Vertical Resolution: 1-2 km

- (See posters, Wednesday)

## Status of HIRDLS data products

- 1. Temperature, Ozone, HNO3, clouds – Released [v2.04.09]
- 2. H2O, CFC-11, CFC-12 – Not ready to release; 			      now most promising for future releases
- 3. CH4, NO2, N2O, ClONO2, N2O5 – Not ready to release.

## List of Validation & related publications

- Alexander et al, Global Gravity Wave Momentum Flux, JGR, In Review.
- Coffey et al, Ozone observations during the Polar Aura Validation Experiment (PAVE) 	in support of EOS Aura validation, JGR, In Review.
- Coffey et al, Airborne Fourier transform spectrometer (FTS) observations 	in support of EOS Aura validation, JGR, In Review.
- Gille et al, The High Resolution Dynamics Limb Sounder (HIRDLS): Experiment Overview, 	Results and Validation Of Initial Temperature Data, JGR, In Review.
- Kinnison et al, Global Observations of HNO3 from the High Resolution Dynamics Limb Sounder (HIRDLS) – First results, JGR, In Review.
- Massie et al, HIRDLS Observations of Clouds, JGR, *Accepted*.
- Nardi et al, Validation of HIRDLS Ozone Measurements, JGR, In Review.
- _Other relevant HIRDLS publications_
- Khosravi et. al. (2007) Retrieval Algorithm and Characterization for the High Resolution Dynamics Limb Sounder (HIRDLS), in preparation for submission to *IEEE Trans. Geosci. Remote Sens.*
- Eden, T., J.J.  Barnett, J.C. Gille,  C.L.  Hepplewhite, C.W.P.  Palmer, J.G.  Whitney (2007), Spectral Characterization of the HIRDLS Flight Instrument from Pre-launch Calibration Data, in preparation.
- Barnett, J.J., J.N. Bracken, K. Djotni, C.L. Hepplewhite, J.L. Moorhouse, O.O. Oduleye, C.W.P. Palmer, D.M. Peters, L.A. Rokke, T.W. Walton, R.E.J. Watkins, J.G. Whitney, J.C. Gille, P.I. Arter, T.D. Eden, B. Nardi (2003), Pre-launch calibration of the NASA AURA HIRDLS instrument, *Proc.* *SPIE ***5152,** 172-180.
- Gille, J.C., J.J. Barnett, J.C.  Whitney, M.A.  Dials, D.M. Woodard, W. Rudolf, A. Lambert, W. Mankin (2003), The High Resolution Dynamics Limb Sounder (HIRDLS) Experiment on Aura,* Proc.* *SPIE ***5152, **162-171.
- Hepplewhite, C.L., J.J. Barnett, J.C. Whitney, C.W.P. Palmer, O.O. Oduleye, T. Walton, M.A. Dials, J.C. Gille, T. Eden, B. Nardi (2005), HIRDLS Functional Performance in Orbit – A summary, Proc. SPIE **5883**, J1-10.
- Moorhouse, J.L., J.J. Barnett, K. Djotni, C.L. Hepplewhite, C.W. P. Palmer, O.O. Oduleye, T. Walton, R.E.J. Waktins, J.G. Whitney, J.C. Gille, P. Arter, B. Nardi (2003), HIRDLS field of view calibration techniques and results, *Proc*. *SPIE*, **5152**, 193-203.

## Slide 31

## Ozone Comparison with ACE-FTS

- Cora Randall

_**Ozone Comparison with ACE-FTS**_

- NH

- SH

- ΔVMR

- %Difference

## Ozone

_**Comparisons with MLS v2.2 Ozone on pressure surfaces [Mercator]**_

**O****3**** **Percent Diff (%)

**O****3**** **Percent Diff (%)

_**Ozone**_