Pathway from the boundary layer to the UTLS

Transcription

1 Pathway from the boundary layer to the UTLS over the Asian summer monsoon region Outline 1. TP ASM (E to W) 2. O 3 H 2 O, cirrus & aerosol Jianchun Bian LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences bjc@mail.iap.ac.cn 3. Dynamics microphysics, chemistry & radiation 4. Extra-tropical TL TTL 5. Sat. & simulation in situ obs. 6. Summary 1

2 1. From Tibetan Plateau to the ASM! TP has been a long-lasting Zhou et al., 1995 topic for atmospheric research (Yeh, 1949, 1950; Yin, 1949; Bolin, 1950).! TOMS measurements show a summertime total ozone valley over TP (Zhou et al., 1995)! Guess: BL pollutants converge to TP, and then are transported to UTLS by ASM updraft, which is induced by the huge elevated heat source (Yeh et al., 1957; Flohn, 1957).! Mechanisms: dynamics, chemistry 2

3 In view of Asia region, ozone valley is a phenomenon of terrain: Good agreement between total O 3 and terrain! Total ozone anomaly (DU) in JJA ( ) JJA OMI total ozone (DU) N Ozone Terrain DU Longtitude (E) Terrain in pressure (hpa) ! Total ozone decreases DU per 100 hpa elevation change! TP terrain causes a reduction of ~20 DU total ozone. Bian et al., AAS, 2010

4 TP & IP share the same ozone profile, but have lower ozone in UTLS relative to non-asm region. 1 Blue Tibet P. (45E-75E) Red Iran P. (75E-105E) Green non-asm Pressure (hpa) Non-ASM Lower O 3 in UTLS SAGE II ozone partial pressure (nb) Bian et al., AAS, 2010

5 267DU = 300 DU + 7 DU 20 DU 20 DU TP Non-ASM Higher trop. Lower_UTLS Terrain +60% 1 (45E-75E) 20% +60% (75E-105E) Budget Pressure (hpa) Non-ASM TP: 267DU Non-ASM: 300 DU ASM UTLS 20DU Terrain 20DU SAGE II ozone partial pressure (nb) Bian et al., AAS, 2010

6 1. From Tibetan Plateau to the ASM! Focus shifts from the TP to the whole ASM region. 6

7 2. From O 3 to H 2 O, cirrus, and aerosol H 2 O! Maximum H 2 O within anticyclone (Rosenlof et al., 1997)! Maximum cirrus & enhanced aerosol (Vernier et al., 2011) H 2 O! H 2 O, cirrus & aerosol are critical for chemistry, radiation Cirrus Bian et al., Chinese JAS,

8 Asian tropopause aerosol layer (ATAL) Anticyclone Anticyclone CALIPSO km ATAL ATAL o N average Vernier et al, GRL, 2011! ATAL impacts also on microphysics. 8

9 Impact on global climate ~ 17 km Lelieveld et al., ACP, 2007 Upward flux! Simulations: the upward water mass flux associated with ASM accounts for 75% of global flux during boreal summertime (Gettelman et al., 2004)

10 3. From dynamics to microphysics, chemistry & radiation! Dynamics: 2 key processes 1. Deep convection (Randel et al., JGR, 2006; Fu et al., GRL, 2007): convective transport + emission source = pathway destination (Yan et al., AAS, 2015) 2. Anticyclone trapping effect (Li et al., GRL, 2005; Park et al, JGR, 2007): bi-mode (Yan et al, AOSL, 2011) 3. Many issues to be investigated: main outflow level, wet scavenge,! Microphysics, chemistry, radiation: 1. formation of cirrus & aerosol 2. super-saturation 3. inhomogeneous/homogeneous nucleation & chemistry 10

11 Tracing CO-maxima within ASM anticyclone by WRF-Chem Indian C. E. China! CO emission: Global Fire+ Asia Anthropogenic! Period: ; no chemistry! Wind:FNL(1 1 ); chemical initial & boundary condition:mozart4 Yan et al., 2015, AAS

12 Simulation and contribution of different emission I-O =30ppb I-O =20ppb I-O =13ppb I-O =2ppb Yan et al., 2015, AAS

13 Pathway of emission from Indian continent Yan et al., 2015, AAS

14 Pathway of emission from Eastern China Yan et al., 2015, AAS

15 Effect of the bimodality of ASM anticyclone! ASMA center has bi-peak distribution zonally (Zhang et al, 2002) Center no. in the longitude during summer Iran mode Tibet mode IM: E TM: E Yan et al., 2011, AOSL

16 Water vapor distribution for different mode Composite analysis Iran mode Tibet mode Yan et al., 2011, AOSL

17 Composition distribution for different mode! IM: Climate ave. IM TM Higher trop. tracers over IP, lower strat. tracers over IP, Opposite over the TP H 2 O(ppmv) CO(ppbv) O 3 (ppbv) Yan et al., 2011, AOSL

18 4. From extra-tropical transition layer to TTL! Although ASM anticyclone locates at sub-tropics (ExTL), it has TTL mixing structure (Pan et al., JGR, 2014). However, somewhat different from TTL, such as TIL, higher top boundary level.! Unknowns: 1. Top & bottom boundary 2. Physical & chemical processes related to cirrus, dehydration, aerosol, and so on; micro-scale waves related to in situ formation of cirrus 3. How to get into tropical pipe or stratosphere from ASM anticyclone?

19 Pan et al., 2014, JGR Tropics 10 N KM 25 N Gettelman et al., 2011, RG Boulder 40N

20 5. From sat. & simulation to in situ measurement Vernier et al., 2015, JGR! ATAL formation mechanisms: 1. Anthropogenic SO 2 emissions (Neely III et al, JGR, 2014) 2. Carbonaceous and sulfate materials (Vernier et al, JGR, 2015) 3. Ammonium nitrate (NH 4 NO 3 ) (Liao et al, communication) True evidence?

21 ! Above and many other related studies have used satellite data and models.! Satellite product lacks of validation over this region, and the vertical resolution is low so many finer structures can t be seen.! We are trying to conduct coincident in situ measurements of water vapor, ozone and particle in the UTLS within the ASM anticyclone.! These observations will be significant for quantifying the moisture transport associated with the ASM, for identifying the transport pathway, and for understanding microphysical process in the ASM-TL. Scientific goals 21

22 Sounding Water vapor, Ozone and Particle (SWOP) campaign at Lhasa and Kunming during the Asian summer monsoon Thanks to Hongbin Chen, Daren Lu, Yuejian Xuan, Jinqiang Zhang, Zhixuan Bai (IAP/CAS) Holger Vömel (GRUAN, DWD), Frank Wienhold (ETH), Dale Hurst, Samuel Oltmans, Emrys Hall, Allen Jordan (NOAA) 22

23 Campaign Locations " ASM anticyclone spans subtropical Asian continent between 20 40N, higher tropopause " KM (25.0N, 102.6E) within southeast edge of anticyclone, influenced by the air mass from outside " LH (29.6N, anticyclone center and consistently within anticyclone limit 23 Bian et al. GRL, 2012

24 Balloon-borne sondes " Compact Optical Backscatter Aerosol Detector (ETH) " NOAA Frost Point Hygrometer (NOAA GMD) " Cryogenic Frost Point Hygrometer (Vömel-DMT) " Electrochemical Concentration Cell Ozonesonde (DMT) " Radiosonde: P, T, U, winds (u,v) (InterMet) CFH & FPH measure the water vapor concentration and RHi by detecting the frost point of the airmass. COBALD detects cloud particle and aerosol by emitting light at two wavelengths (455nm, 870nm), and receiving the back-scattered signal. 24

25 Six IOPs during Aug CFH/ECC 3 Cobald 2013 Aug CFH/ECC 18 Cobald LS 2009, Aug CFH/ECC 2011, Sep CFH/ECC 2012, Aug 11-Sep 6 21 CFH/FPH 38 ECC, 12 Cobald 2014, Aug CFH/ECC/Cobald KM 25

26 Balloon-borne Sondes & Timing " Ozone: ECC ozonesonde (99) " Water vapor: CFH-RS80 (11), CFH-iMet (54), FPH-iMet (15) " Cloud and aerosol: COBALD (43) " Once or twice daily " Kunming: Aug 7-13, 2009, CFH/ECC/RS80 (11 sets) Sep 12-15, 2011, CFH/ECC/iMet (4 sets) Aug 11-Sep 6, 2012, CFH (6), FPH (15), COBALD (12), ECC (38) Aug 13-22, 2014, CFH (10), COBALD (10), ECC(10) " Lhasa: Aug 22-28, 2010, CFH/ECC/iMet (9 sets), CFH/COBALD/ECC/iMet (3 sets) Aug 3-26, 2013, CFH/ECC/iMet (6 sets), CFH/COBALD/ECC/Imet (18 sets) 26

27 First in situ measurement of UTLS H 2 O and O 3 during ASM Bian et al, JGR, 2012 Kunming Lhasa H 2 O O 3 RHi - Supersaturation 27

28 RHi distribution changes with temperature

29 Aerosol and cirrus BSR H2O mixing ratio RHi BSR_Red BSR_Blue Altitude (km) RHi (%) Water vapor mixing ratio (ppmv) 29

30 Asian tropopause aerosol layer is indeed observed by in situ measurements! Vernier et al, JGR, 2015 True evidence? To be confirmed 30

31 To be confirmed by StratoClim aircraft campaign Russian M-55 Geophysica Rex et al, ACAM, 2013

32 Summary: # knowns << # unknowns Park et al, JGR, 2009 So, we come here to find the true evidence! Thank you very much 32