Southern Ocean Challenges Workshop Seattle, 18-19 March 2014

1. Southern Ocean Challenges Workshop Seattle, 18-19 March 2014 The CAPRICORN Project: Clouds, Aerosols, Precipitation Radiation and atmospherIc Composition Over the southeRN ocean Australian Participants : Alain Protat, Peter May, Eric Schulz, Hongyan Zhu (CAWCR / BOM) Charmaine Franklin, Melita Keywood (CAWCR / CSIRO) Christian Jakob, Steve Siems, Michael Reeder, Danijel Belusic (Monash University) Todd Lane, Robyn Schofield (The University Of Melbourne) Simon Alexander, Andrew Klekociuk (Australian Antarctic Division) Murray Hamilton (The University of Adelaide) International Participants : Yong Hu (NASA) Christopher Hoyle (Paul Scherrer Institute, Switzerland) Thomas Peter (ETH, Switzerland)

2. Why do we care ? Courtesy of J. Haynes

3. Why do we care ? Mace et al. 2009 Hypothesis : Not enough low-level clouds in models and / or inaccurate microphysics ? 90-95% !

4. Why do we care ? Trenberth and Fasullo (2010) Radiation biases correlate with global climate sensitivity Net TOA radiation over SH Climate sensitivity [K for 2xCO2] CloudSat-CALIPSO : pervasiveness of SLW in the SHB Impact on radiative budget & cloud processes ? Ceppi et al. (2012) SH jet latitude biases in CMIP5 linked to SW cloud forcing Causal connection of the cloud bias to SH dynamics ? J. Delanoë (unpublished) The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

5. Why do we care in Australia? ACCESS climate model evaluation work Z. Sun (BOM): Net SW surface radiation and LWP biases H. Zhu (BOM): DJF Rainfall bias DJF C. Franklin (CSIRO): cloud biases with COSP CloudSat Too much optically thin clouds Not enough optically thick clouds Too much drizzle LWP largely underestimated Not enough non-precip clouds Cloud - rain conversion too efficient ISCCP The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

6. Regime dependence of model skills in the SO C. Jakob, S. Mason, J. Fletcher (Monash), A. Protat (BOM) The ACCESS climate model doesn’t produce any mid-topped clouds ! But loves his fronts and cirrus a bit too much … S4 S5 S7 S8 The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

7. CAPRICORN Science Plan • Southern Ocean critical to global and Australian climate and weather. • Climate models poorly represent the energy balance in that region. • Southern Ocean is a very unique "pre-industrial" (?) environment (pristine air, SLW occurrence, high low-level shear, complex boundary layer, S. Siems's talk) • Also a data sparse area – satellite observations and products are critical to investigate processes at regional scale. But require thorough evaluation. • The main objective of CAPRICORN is therefore to acquire a comprehensive database about Southern Ocean cloud systems in order to : • Characterize the cloud (macrophysics, microphysics, radiative effect) , aerosol (microphysics and chemistry), precipitation, and boundary layer properties of SO cloud systems and their variability as a function of the large-scale forcing (using regimes); • Evaluate A-Train cloud macrophysics, microphysics, CALIPSO-derived ocean products, aerosol / cloud discrimination, and CloudSat / GPM rainfall properties; • Evaluate the current skill of the suite of ACCESS models at different scales (from high-resolution models to NWP to climate models) to reproduce these properties of the Southern Ocean cloud systems. • Run and analyze sensitivity experiments on model parameterizations to improve models

8. CAPRICORN Strategy • We propose to address the CAPRICORN objectives using • Regular cruises over the Southern Ocean to get regional-scale samples (MNF Investigator) • Long-term ground-based observations at Macquarie Island to get high-resolution high-quality measurements (but at a single point), • (Validated) satellite observations to study SO processes at regional + seasonal + interannual scales. • Missing bit: aircraft in-situ data for process studies and verification of remote sensing retrievals from ground, ship, and space ! • The ISCCP “cloud regimes” over the Southern Ocean will be used as a framework to better understand the relationship between the large-scale state and the cloud-aerosol-radiation-precipitation processes, and for model evaluation and improvement.

9. The Marine National Facility (MNF) New research vessel : the RV Investigator Some numbers : 93.9 m long, up to 300 days at sea per year (60 days max per voyage) It can accommodate 40 scientists onboard It is being constructed in Singapore – commissioning should start in 05 / 2014 (been delayed) Secured instrumentation : Dual-pol C-band Doppler radar (MNF/BOM) Cloud radar and lidar (BOM) Radiative and air-sea fluxes (BOM) Atmos. composition in-situ properties (CSIRO) Ozone and COBALD backscatter sondes We would need : A microwave radiometer (ideally 3-channel) Radiosonde launch facility (lease ? borrow ?) Wind profilers (?) The MNF is very open to hosting new instruments The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

10. The Marine National Facility (MNF) In-situ meteorological observations (Eric Schulz, BOM): Main objective is to calculate the 1-min bulk turbulent fluxes and then net fluxes of heat, mass & momentum Wind speed and direction Air temperature, humidity, pressure Precipitation SW and LW radiation SST On request the following parameters can also be measured: Total particulate organic carbon (POC) Phytoplankton physical/optical properties Photo synthetically-active-radiation, Sea surface salinity, Currents, Profiles of ocean temperature & salinity,   pCO2, ocean oxygen, biological indicators, waves … The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

11. The Marine National Facility (MNF) In-situ atmospheric composition observations (Melita Keywood, CSIRO): Permanent Scanning Mobility Particle Sizer (SMPS): 10 – 700 nm particle size distribution (5 min res.) MultiAngle Atmospheric Photometer- aerosol absorption at one l and multiple angles in real time and calculates BC Nephelometer – aerosol scattering at 520, 807 and 400 nm in real time Cavity ringdown – CO2, CH4, N2O and CO in real time Ozone monitor – Tropospheric ozone concentrations in real time NOx monitor – measures NO and NOx and calculates NO2 in real time Sun Photometer – measures AOD CMAR instrumentation for campaigns CCN counter –ability of a particle to act as a cloud condensation nuclei in real time Nano-SMPS: 3 – 150 nm nm particle size distribution (5 min res.) Aerosol Particle sizer (APS): 500 nm – 10 mm nm particle size distribution (5 min res.) Aerosol Chemical Speciation Monitor (ACSM-ToF) – measures the composition of particles between 250 nm and 2.5 microns at 5-10 minute resolution Cascade Impactor- collects size-resolved aerosol samples for post analysis. Proton Transfer Mass Spectrometer (PTRMS) – concentration of VOCs at 5-10 minute intervals On-line GC – measures concentration of VOCs at 30 minute intervals Sequencer- collection of VOC and carbonyl samples on absorbent tubes for post analysis CN counters –concentration of the number of particles greater than 3 and 10 nm in real time

12. Macquarie Island (ACRE Proposal) • ACRE: Antarctic Clouds and Radiation Experiment • Led by S. Alexander (AAD) – come to his talk ! • Component relevant to CAPRICORN : • Collection of a 1-year cloud / aerosol / precip dataset at Macquarie Island (54S). • IOP proposed for March 2016 to March 2017 • Proposal is to deploy : • CAWCR cloud radar, cloud and aerosol lidar, 2D video and / or impact disdrometer • CSIRO cloud condensation nuclei (CCN) counter (aerosols which form cloud droplets) • U.S. DoE ARM microwave radiometers, radiation package, sun photometer / MFRSR • Can consider additional, low-maintenance instruments if there is interest from the community • Waiting for AAD call for science applications The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

13. CAPRICORN Planning May – Jun. 2014 : First sea trial with the C-band dual-pol radar July – Dec. 2014 : Integration of CAWCR cloud radar / lidar/ radiometer. Dec. 2014 – March 2015 : many cruises over the Southern Ocean (not led by us) where the C-band radar will be operating (but no cloud instrumentation). Dec. 2015 – March 2016 (proposal granted), 1 month : dedicated cruise (led by us) with C-band radar, cloud radar, lidar, microwave radiometer, surface radiation and rainfall, radiosondes including polarsondes (liquid versus ice) and ozone sondes, aerosol lab Dec. 2016 – March 2017 (proposal granted), 1 month : same as above. CAWCR cloud radar / lidar could be at Macquarie Island for ACRE though … Dec. 2017 – March 2018 (proposal granted too !), 2 months : SOCRATES …

14. Some ongoing work • Franklin (CSIRO) + Sun (CAWCR): Sensitivity experiments with ACCESS • Changing to Franklin (2008) autoconversion scheme shows significant improvements – produces more optically thicker low and midlevel clouds. Overall SW bias reduced by 43%. Fletcher + Jakob (CAWCR): Sensitivity experiments with ACCESS Reducing autoconversion, ice fall speed, min T of heterogeneous nucleation … The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

15. Mason, Jakob, Fletcher (Monash) Protat (BOM) SO cloud regimes: 88% 20% 36% 41% Refined mid-topped regimes ω ω ω ω ω Meteorology, macrophysics & microphysics: Mason et al. 2014, sub. CTP-τ TOA CRESW (ACCESS1.3 - ISCCP): (ACCESS1.3 - ISCCP): ΔTCC=-20.1%

16. Thank you Alain Protat The CAPRICORN Project: Clouds, Aerosols, Precipitation Radiation and atmospherIc Composition Over the southeRN ocean Email: a.protat@bom.gov.au Thank you