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--- aerocom:indirect [2013-10-15 23:23:37]
steve.ghan@pnnl.gov
+++ aerocom:indirect [2014-03-25 14:56:22]
steve.ghan@pnnl.gov
@@ Line 26: / Line 26: @@
  *   fix_1850: as in fix_2000, but for pre-industrial emissions  \\
+== Motivation ==
+The proposed study is designed to address two key areas of uncertainty: 1) the sensitivity of cloud liquid water path to aerosol, and 2) the competition between heterogeneous and homogeneous nucleation of ice crystals.
+To address issue 1), we’ve added daily and monthly diagnostics that can be compared with CloudSat and MODIS retrievals of the relationship between the aerosol optical depth and the probability of precipitation (Wang et al., 2012).
+To address issue 2), we’ve added experiments in which heterogeneous nucleation is neglected for T%%<%%-37C, and in which ice nucleation for T%%<%%-37C is a prescribed function of temperature (Cooper, 1986).
+We also have added a requirement to nudge toward analyzed winds, which we’ve found greatly reduces the noise due to natural variability without significantly inhibiting the cloud response to the aerosol. (Kooperman et al., 2012). Simulations of six years duration each should be sufficient for all experiments.
+To facilitate analysis and comparison before the 2013 AeroCom meeting, the results should be submitted to the AeroCom repository by December 1, 2013. Please contact steve.ghan@pnnl.gov and xiaohong.liu@pnnl.gov when your results have been submitted.
+Cooper, W. A.: Ice initiation in natural clouds. precipitation enhancement – a scientific challenge, Meteor. Mon., 43, 29–32, 1986.
+Kooperman, G. J., M. S. Pritchard, S. J. Ghan, R. C. J. Sommerville, and L. M. Russell, 2012: Constraining the influence of natural variability to improve estimates of global aerosol indirect effects in a nudged version of the Community Atmosphere Model 5. J. Geophys. Res., 117, doi:10.1029/2012JD018588.
+Wang, M., S. Ghan, X. Liu, T. L’Ecuyer, K. Zhang, H. Morrison, M. Ovchinnikov, R. Easter, R. Marchand, D. Chand, Y. Qian, and J. E. Penner, 2012: Strong constraints on cloud lifetime effects of aerosol using satellite observations. Geophys. Res. Lett., 39, 15, doi:10.1029/2012GL052204.
@@ Line 51: / Line 70: @@
 (1) 2D diagnostics for evaluation with satellite data
-years (years 2006-2010) of 3-hourly data from the PD run
+years (years 2006-2010) of 3-hourly instantaneous data from the PD run
 ======
 ^ name 	^ long_name (CF if possible) ^	units ^	description ^
@@ Line 63: / Line 82: @@
 | clt | cloud_area_fraction | 1 | Fractional cover by all clouds |
 | lcc | liquid_cloud_area_fraction  | 1 | Fractional cover by liquid water clouds |
-| lwp | atmosphere_cloud_ice_content | kg m-2 | grid cell mean liquid water path for liquid water clouds |
+| lwp | atmosphere_cloud_liquid_path | kg m-2 | grid cell mean liquid water path for liquid water clouds |
-| iwp | atmosphere_cloud_ice_content | kg m-2 | grid cell mean ice water path for ice clouds |
+| iwp | atmosphere_cloud_ice_path | kg m-2 | grid cell mean ice water path for ice clouds |
 | icr | cloud-top_ice_crystal_effective_radius | m | grid cell mean effective radius of crystals at top of ice clouds |
 | icc | ice_cloud_area_fraction | 1  | Fractional cover by ice clouds |