Interactions radiation-cloud-aerosols

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2 Interactions radiation-cloud-aerosols Maria Assunção Faus da Silva Dias Departamento de Ciências Atmosféricas Universidade de São Paulo

3 Summary Aerosol cloud microphysics Aerosol - radiation

4 Aerosol layer topped by thermal inversion, absoption and scattering of radiation Shading by aerosol layer impact surface energy budget, change low level stability, change cloud features and rainfall Ingestion of parcels with high concentration of CCN impact cloud features and rainfall Changes on cloud features and rainfall impact cloud dynamics, cloudenvironment interactions, teleconnections, global energy budget

5 Radiation budget for Planet Earth

6 KOREN ET AL 2004

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8 Koren et al 2008

9 Biomass burning aerosol effect on rainfall

10 CO conc. (ppb)

11 Biomass Burning Emissions > 5000 fires GOES-8 WF_ABBA Local smoke plume (deforestation fires) (picture from M. Andreae) smoke smoke smoke Regional smoke plume ~5 millions km 2 (Prins et al. 1998) 15:31

12 Aerosol optical thickness 500 nm AOT 500 nm Nov-98 Jan Dec-98 Mar Feb-99 Aeronet measurements in Alta Floresta and Rondonia Artaxo et al 31-Mar-99 May-99 Alta Floresta AERONET Aerosol Optical Thickness Jan 99 - Nov May-99 Jul Jul Aerosol Optical Thickness Aeronet Abracos Hill Rondonia 500 nm Sep Aug-99 Nov Oct Dec-99 Jan Jan-00 Mar Mar-00 May May Jun-00 Jul Aug-00 Sep Oct-00 Nov Nov-00 Jan Jan Feb-01 Mar Apr-01 May Jun-01 Jul Jul Sep-01 Sep Nov-01 Nov Dec-01 Jan Feb-02 Mar Apr May-02 May Jul-02 Jul Sep-02 Sep Oct Dec-02 Nov-02

13 Rainfall accumulation Aerosol effects Longo et al, 2003 Radiation Radiation budget in aerosol layers Colder surface, warmer lower troposphere =stabilizing effect less clouds less rainfall? Cloud microphysics Cloud albedo Cloud lifetime Inhibit rainfall in warm clouds Deep clouds? Warm clouds Aerosol Concentration Scheme of aerosol effects on precipitation Accumulated rain Maritime & moderate (wet) continental clouds (like GATE and PRESTORM) Khain et al, 2003 Dry unstable situation (like Texas clouds) Aerosol concentration Cold clouds

14 Freitas S.., Longo. Silva Dias, M. A. F., Chatfield, R., Silva Dias, P., Artaxo, P., Andreae, Grell, Rodrigues, Fazenda, Panetta, J (CATT- BRAMS) Atmos. Chem. Phys. meio_ambiente

15 AOT (550 nm) from model (40 km resolution)

16 Solar radiation 16Z19sep2002 without and with the aerosol effect

17 Δtemperature 16Z19sep2002 T2 = temperature with aerosol T1 = temperature without aerosol 3 Km Surface layer 3 km

18 3: (lat,lon)= (-12.5, -55) aot(550)=3.9

19 Reduction on the Convective precipitation (mm) DP = (P - P aer ) GOES-8 IR :45Z

20 Where are the Most Intense Thunderstorms on Earth? Zipser et al 2006 BAMS

21 Camponogara, Silva Dias, Carrió 2013 ACPD, 2014 ACP (accepted)

22 North cases Sep-Dec Data from Mesoscale Convective Systems fed by Northerly winds with variable aerosol concentration TRMM 3B42 v.7 3 hr data added up to daily values (mm/day)- RR Aerosol Optical Depth - AOD from AERONET daily level 2, 400 nm NCEP Reanalysis 2

23 Combined EOF using RR mm/day AOD for different AERONET stations For the MCS region: RR daily rainfall ω 500 avg RH mb AOD

24 Direct radiation effect of the aerosol plume AOT 550 nm Solar radiation at the suface aot(550)=3, 9 o Possible effect of biomass burning delaying the onset of the rainy season? T = -3.5 o C

25 Li & Fu, 2004 Transition of the Large-Scale Atmospheric and Land Surface Conditions from the Dry to the Wet Season over Amazonia as Diagnosed by the ECMWF Re-Analysis. J. Climate Lower LH in the observations: may be an indication of the aerosol effect ECMWF LH OBS Rebio Jaru

26 Zhang et al 2009 Impact of biomass burning aerosol on the monsoon circulation transition over Amazon (GRL) Ensemble simulation with RegCM3 September 2002 AERO radiative effects of biomass burning aerosol CONT no aerosol AERO-CONT a) Diff rainfall b) Diff lapse pot temp lapse-rate lower atm c) Diff surf pressure and moisture flux 925 hpa d) Diff vertical velocity 65 W

27 PM10 Concentration [ug/m³] LBA-Dry to Wet Season Campaign Aerosol Concentration TEOM PM 10 SMOCC 2002 Pasture Site FNS /set 06/set 11/set 16/set 21/set 26/set 01/out 06/out 11/out Date and GMT Time 16/out 21/out 26/out 31/out 05/nov 10/nov 15/nov

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31 Andreae, Rosenfeld, Artaxo, Costa, Frank, Longo, Silva Dias 2004.Smoking rain clouds over the Amazon - Science

32 n n n t D D D D D N D n exp 1 ) ( ) ( 1 Shape parameter in cloud droplet diameter distribution Gonçalves, Martins, Silva Dias, 2008, Atmos Research

33 FREQUÊNCIA (%) Frequency of shape parameters for all flights CLEAN LIMPO POLUÍDO POLLUTED PARÂMETRO DE FORMA

34 Martins, Silva Dias, Gonçalves, 2009 JGR Vertical structure of cloud and ice water mixing rate observed at the time of maximum liquid water path CCN300 CCN450 CCN600 CCN900

35 0.3 Flashes/km 2 /month Flash Density (FL/km 2 /mo) TRMM-PR IWC (Z-M) 6.00 LIS Flash Density vs. 7-9 km IWC vs. LIS Flash Density 5.00 y = x R 2 = TRMM PR: WARM/WET SEASON 1998/99/00 Ice Water (g m 3 ) y = x x R 2 = LAND IWC g m OCEAN Height (km) Afr. Congo (D-F) Height (km) Sub-trop. Africa (D-F) N. Australia (D-F) Amazon (D-F) Brazil (M. Grosso) (D-F) Warm-pool (D-F) KWAJ. (J-A) G. Mexico (J-A) Florida (J-A) SE. US (J-A) Atlantic ITCZ (D-F) S India (J-A) N India (J-A) EPIC3 (6-12 N) (J-A) S. China Sea (J-A) Indian Ocean (S-N) Gulf Str. (J-A) Argentina (D-F) IWC (g/m 3 ) Wet Season ( ): LIS Flash Density vs. IWC (7-9 km) =AMZ/Monsoon =Ocean =Ocean/Coast =Land Cntrl. Brazil N. India S. India WP Warm-pool Sub-Congo Africa EPIC Congo AMZ AMZ (DJF) IWC (g/m 3 ) Florida AMZ (SON) Gulf Stream

36 Albrecht, Morales, Silva Dias 2011:Electrification of precipitating systems over the Amazon, J. Geophys. Res.

37 Williams et al 2002Contrasting convective regimes over the Amazon: Implications for cloud electrification JGR Wet Season Easterlies Wet Season Westerlies Dry Season Williams et al, 2002

38 Mean total aerosol concentration for each type of precipitating system when first detected by the radar. For LBA campaigns TRMM/LBA and SMOCC (SW Amazon) polluted clean

39 Reutter et al 2009, Atmos. Chem. Phys. An updraft-limited regime that is characterized by low w/n CN ratios (< 10 4 m s 1 cm 3 ), low maximum values of water vapour supersaturation (S max < 0.2%), low activated fractions of aerosol particles (N CD /N CN < 20%). In this regime N CD is directly proportional to w and practically independent of N CN. No sensitivity to number concentration of aerosol. An aerosol-limited regime that is characterized by high w/n CN ratios (> 10 3 m s 1 cm 3 ), high maximum values of water vapour supersaturation (S max > 0.5%), and high activated fractions of aerosol particles (N CN /N CN > 90%). In this regime N CD is directly proportional to N CN and practically independent of w. As the number concentration of aerosol increases there is a shift to ice phase microphysics. HIGH AEROSOL LOAD DRY SEASON AMAZON CLEAN WET SEASON AMAZON

40 Reutter et al 2009 INDOEX Ice phase INDOEX Amazon Dry season Amazon Wet season

41 The aerosol effect Aerosol absorb and scatter solar radiation changing the temperature structure of the lower atmosphere and surface Aerosol act as Cloud Condensation Nuclei (CCN) and change the processes of rainfall production Cloud droplets : water vapor condenses on CCN. Large numbers of CCN = competition for available water vapor

42 1) Koren et al 2004 Measurement of the Effect of Amazon Smoke on Inhibition of Cloud Formation. Science Smoke lowers cloud fraction BUT Subsidence also lowers cloud fraction and increases smoke concentration 2) Albrecht et (JGR) Electrification of precipitating systems over the Amazon: Physical processes of thunderstorm development. Journal of Geophysical Research increasing sinking motion with effects: - Reduced cloud fraction - Increases concentration of smoke particles (reduces dispersion) - Aerosol more effective in changing rainfall when atmosphere is not excessively polluted

43 Recent results from GoAmazon

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47 Obs and models indicate Radiative effect of aerosol may delay the onset of the rainy season (monsoon season) There is sensitivity to aerosol number concentration in the wet season More aerosol -> deeper convection, more ice, more ligthning In the dry season and transition seasons convection is updraft limited and shows no sensitivity to aerosol concentration Deep convection will be limited by the available thermodynamic instability and dynamic lifting mechanisms

48 Conclusion

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50 Betts and Silva Dias, 2010, JAMES Progress in Understanding Land-Surface-Atmosphere Coupling from LBA Research