which does not cover the whole range of observed ice number density (0.005-0.2 cm-3) (see Fig 5.19). Figure 5.19 model result of ice number density and relative humidity versus time. The cirrus model is forced with the balloon observed temperature fluctuations with IN concentration of 0.005 cm-3. Summary and conclusion In this chapter, we have shown the effect of single and multiple gravity waves on cirrus clouds through investigations using the Advanced Particle Simulation Code cirrus model. We progressively moved to more complex and realistic gravity wave simulations resulting in the work in which we use balloon observations of temperature fluctuations taken from months of balloon observations of TTL conditions. Our model results using these gravity wave forcings show many results but most importantly we show that the commonly observed TTL cirrus properties are consistent with gravity wave forcings only when glassy nucleation is present. This suggests that glassy or a similar common and abundant aerosol nucleator must be present to explain observations. I now present the more specific results of the chapter: Single gravity waves with different amplitude and time periods of 20-100 cm/sec and 90s respectively have been implemented in our cirrus model for both homogeneous and heterogeneous runs. The freezing threshold and cloud properties are determined by the amplitude and frequency of gravity waves. Forming cirrus cloud along the homogeneous pathway needs higher wave amplitude and lower wave frequency than cloud formed on glassy aerosol particles.
which does not cover the whole range of observed ice number density (0.005-0.2 cm-3) (see Fig 5.19). Figure 5.19 model result of ice number density and relative humidity versus time. The cirrus model is forced with the balloon observed temperature fluctuations with IN concentration of 0.005 cm-3. Summary and conclusion In this chapter, we have shown the effect of single and multiple gravity waves on cirrus clouds through investigations using the Advanced Particle Simulation Code cirrus model. We progressively moved to more complex and realistic gravity wave simulations resulting in the work in which we use balloon observations of temperature fluctuations taken from months of balloon observations of TTL conditions. Our model results using these gravity wave forcings show many results but most importantly we show that the commonly observed TTL cirrus properties are consistent with gravity wave forcings only when glassy nucleation is present. This suggests that glassy or a similar common and abundant aerosol nucleator must be present to explain observations. I now present the more specific results of the chapter: Single gravity waves with different amplitude and time periods of 20-100 cm/sec and 90s respectively have been implemented in our cirrus model for both homogeneous and heterogeneous runs. The freezing threshold and cloud properties are determined by the amplitude and frequency of gravity waves. Forming cirrus cloud along the homogeneous pathway needs higher wave amplitude and lower wave frequency than cloud formed on glassy aerosol particles.
sardar_thesis_Aug_23.docx