Susannah Burrows 1,2 w ith contributions from : C. Hoose 3 , U. Pöschl 2 , M. G. Lawrence 2,4 - PowerPoint PPT Presentation

dirk
slide1 n.
Skip this Video
Loading SlideShow in 5 Seconds..
Susannah Burrows 1,2 w ith contributions from : C. Hoose 3 , U. Pöschl 2 , M. G. Lawrence 2,4 PowerPoint Presentation
Download Presentation
Susannah Burrows 1,2 w ith contributions from : C. Hoose 3 , U. Pöschl 2 , M. G. Lawrence 2,4

play fullscreen
1 / 9
Download Presentation
Susannah Burrows 1,2 w ith contributions from : C. Hoose 3 , U. Pöschl 2 , M. G. Lawrence 2,4
126 Views
Download Presentation

Susannah Burrows 1,2 w ith contributions from : C. Hoose 3 , U. Pöschl 2 , M. G. Lawrence 2,4

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. The potential influence of marine biological activity on ice nuclei concentrations over the Southern Ocean Susannah Burrows1,2 with contributions from: C. Hoose3, U. Pöschl2, M. G. Lawrence2,4 1 – Pacific Northwest National Laboratory 2 – Max Planck Institute for Chemistry 3 – Karlsruhe Institute of Technology 4 – Institute for Advanced Sustainability Studies Burrows, S. M., Hoose, C., Pöschl, U., and Lawrence, M. G.: Ice nuclei in marine air: biogenic particles or dust?, Atmos. Chem. Phys., 13, 245-267, doi:10.5194/acp-13-245-2013, 2013.

  2. Do biological / biogenic particles matter for ice nuclei (IN) populations? • Globally, the most-important and best-studied ice nuclei are dust (and soot), BUT: • Some biological / biogenic particles are more efficient IN than dust, particularly at warmer temperatures. • Might induce freezing earlier, changing cloud development • Emerging picture: a possible role for biological / biogenic particles as IN under certain conditions: • Possible role of organic / biological material in enhancing IN activity of dust (Schnell and Vali, 1972; Pratt et al., 2009; Conen et al., 2011, others) • Pristine, biologically active continental environments in absence of dust (“green ocean”) (Prenni et al., 2009) • Warm, low-altitude mixed-phase clouds (Spracklen and Heald, 2013) • Marine environments? (Bigg, 1973; Schnell and Vali, 1976; Burrows et al., ACP, 2013, Knopf et al., 2012, others)

  3. Measurements of IN concentrations in marine air

  4. IN concentrationscomparedtoChl-a distribution In situ data: Bigg, 1973; Chlorophyll: MODIS climatology Schnell and Vali (1976): Possible marine biological source of IN? Chl-a in µg m-3 B73 IN counts (different color scale) Burrows et al., ACP, 2013

  5. Marine biological IN estimate Satellite data: proxies for marine biological activity (POC, Chl-a) Model parameterization: Sea spray emissions In situ data: IN concentration in marine plankton bloom Intermediate result from simulations: Particulate organic matter in sea spray Result: IN estimate in sea spray Comparison with filter measurements and estimated dust IN concentrations Comparison at -15°C (from B73) Burrows et al., ACP, 2013 Satellite: POC

  6. Simulated POM concentrations Burrows et al. (2013) Vignati et al. (2010) Particulate organic matter (POM), μg m-3 Burrows et al., ACP, 2013

  7. Comparison of proposed marine biological IN distribution with estimated dust IN distribution Burrows et al., ACP, 2013

  8. Marine biological IN: percent contribution to total simulated IN(total = dust + marine biological) - compared at -15°C - in MBL - annual mean UPPER Upper bound: BIO-IN ∙10 {or dust IN ∕ 10 } BEST Burrows et al., ACP, 2013

  9. Moving sea spray chemistry forward Burrows et al., ACPD, 2014 Burrows et al., ACPD, 2014 Empirical parameterizations  semi-mechanistic Chl-a (correlated)  surfactants (causal) Extrapolate from blooms  Account for different chemistry in gyres Gantt et al., 2011