Chemical Composition and Dynamics of the Upper Troposphere and the Lower Stratosphere

(CCD-UTLS), Id. 10577

Viktoria Sofieva, and the CCD-UTLS team European:

Finnish Meteorological Institute

Chinese: Institute of Atmospheric Physics (IAP), CAS

National Satellite Meteorological Center (NSMC), CMA

1. Assessment of satellite data on chemical composition in UTLS 2. Dynamical and chemical structures of the UTLS and its variability 3. Multi-scale variability of stratospheric ozone 4. Climatology of the stratospheric aerosol layer and its variability 5. Updated ozone climatology and its relation to tropopause/multiple tropopauses

Overview of the results

Objective 1: Assessment of satellite data in the UTLS

Summary of the validation against ozonesondes

Hubert et al., AMTD, 2015 Hubert et al., Ozone_cci PVIR, 2014

• Usually, biases are within ± 20% • Large positive bias for GOMOS V6 is not observed in advanced (alternative) retrievals • Data from OSIRIS, ACE-FTS and MIPAS have already been used for scientific studies in the

UTLS

Cortesy of D.Hubert, BIRA

Satellite measurements

+ retrieval

WACCM model

Objective reality Theory

Distortions Approximations

Better understanding of data Better understanding

of model accuracy

E. Kyrölä et al.: Comparison of GOMOS measurements with the simulations by the WACCM model

Presentation by Erkki Kyrölä

Best star in the sky: Sirius, in Arctic Ozone

WACCM GOMOS

year-2000

Presentation by Erkki Kyrölä

Development of GOMOS retrievals in the UTLS • Motivation from validation:

Operational GOMOS v6 has a bias up to 100% in the UTLS (especially large in tropics)

• Validation against NDACC ozonesondes: dramatic reduction of UTLS biases

• The main effect comes from the change in the aerosol model.

• The new UTLS dataset show similar geophysical features as other satellite instruments.

• Comparison against OSIRIS profiles show better agreement.

Poster by Janne Hakkarainen

Animation of comparisons against OSIRIS profiles

Lower Stratosphere

Upper Troposphere

Strat. intrusion of PV and O3

Convective transport of CO and H2O

Data

Models

Effects of convective vertical transport on distribution of atmospheric composition in UTLS

On 21 July 2012, Beijing was hit by an unprecedented extreme torrential rainfall event.

AIRS, OMI and other instruments are used to monitor the effects of convective vertical transport on changes of atmospheric composition in the UTLS.

Presentation by Fuxiang Huang

35 -75% increase in H2O

10-30% decrease in UTLS ozone

UTLS response to Asian Summer Monsoon www.nc-climate.ncsu.edu http://www.sciencedaily.com

• The ASM contains a strong anti-cyclonic vortex in the UTLS, spanning from Asia to the Middle East

• The ASM has been recognized as a significant transport pathway for water vapor and pollutant to enter the stratosphere

• There are still several open questions related the ASM influence

ASM influence on ozone as seen by satellite instruments

Ozone mixing ratio (ppb) at 100 hPa in Jun-Aug, all available years

Comparison with new models covering the troposphere and the stratosphere

MIP

AS

SIL

AM

v 5

.5

ozone mixing ratio (ppb) at 100 hPa

June 2010 July 2010 August 2010

Seasonal cycle in the tropical UTLS

• Approx. factor-of-two variations in strength of upwelling and temperature changes up to 8 K Faster upwelling and colder temperatures during boreal winter

• Annual cycle is observed exclusively above ~15 km • Original explanation:

Tropical cycle is a response to the annual cycle of the stratospheric planetary wave forcing in winter-spring high latitudes

• Recent analyses Importance of extratropical waves dissipating in subtropics Planetary waves generated within the tropics

• Important consequence: vertical transport of trace constituents Especially important for ozone having a strong gradient across TTL

ECMWF temperature (K) 20S-20N

Seasonal cycle in the tropical UTLS ECMWF temperature (K)

OSIRIS ozone partial pressure (nbar)

20S-20N

20S-20N

Ozone seasonal cycle in the tropical UTLS

20S-20 N, 100 hPa

• Reproducing the seasonal cycle is the test for climate model intercomparison

• The figure is adapted from CCMVal report

Amplitude of annual cycle

Gettelman et al., 2010

Ozone seasonal cycle in the extra-tropical UTLS

Heg

glin

et a

l., 2

010

Hegglin et al., 2010

CCMVal report

diurnal (day/night)

synoptic scale (e.g., SSW)

intra-seasonal (e.g., MJO)

Seasonal (e.g., monsoon)

inter-annual (e.g. QBO/ENSO)

semi-annual (e.g., SAO)

decadal (e.g. solar cycle)

Small-scale (advection,

waves)

Satellite data

Models

DRAGON-2 and DRAGON-3

Started in DRAGON-3

Significant progress during DRAGON-3

Intra-Seasonal Variation in the Wintertime Stratospheric O3

Eastward propagation of enhanced convections

Date

Indian Ocean Pacific Ocean East

1 2

3

It takes the MJO ~1–2 months to travel around the Tropics.

Intra-Seasonal Variation in the Wintertime Stratospheric O3

Eastward propagation of enhanced convections

Date

Indian Ocean Pacific Ocean East

1. EQ Indian Ocean

2. Maritime Continent

3. EQ Western Pacific 1

2 3

1. EQ Indian Ocean 2. Maritme Continent 3. EQ Western Pacific

Three geophysical locations selected:

MJO-related disturbances of O3 column (200–20 hPa)

ERA-Interim (DJF, 2004-2010) It takes the MJO ~1–2 months to travel around the Tropics.

Presentation by Chuanxi Liu

Satellite Measurements of the Madden–Julian Oscillation in Wintertime Stratospheric Ozone over the Tibetan Plateau and East Asia

20-200 hPa MJO-related O3 anomalies and 200 hPa geopotential anomalies

Phase 3

Phase 4

Phase 5

Phase 6

Vertical distribution MJO-related O3 anomalies Poster by Yuli Zhang

Tropospheric ozone long-term changing trends and impacting factors over North China

1.28 DU/decade

-1.46 DU/decade

1979 –2013

Presentation by Fuxiang Huang

• Talk by Erkki Kyrölä: – GOMOS versus WACCM

• Talk by Chuanxi Liu – Influence of tropical intra-seasonal variations on stratospheric

ozone • Talk by Fuxiang Huang:

– Sateillite observation of the extreme rainfall event over China • Poster by Janne Hakkarainen:

– Optimized GOMOS retrievals in the UTLS • Poster by Yuli Zhang:

– Influence of Madden-Julian oscillation on wintertime stratospheric ozone over the Tibetan Plateau and East Asia