**5. Radiative effects of ice clouds: CNIR versus C**

The calculations of model domain mean simulation data show that *PEWV* is insensitive to radiative effects of ice clouds on 4 June, whereas the exclusion of radiative effects of ice clouds decreases *PEH* (Table 1). The removal of radiative effects of ice clouds increases *PEWV,* but it barely affects *PEH* on 5 June. The elimination of radiative effects of ice clouds decreases *PEWV* and *PEH* on 6 June. The exclusion of radiative effects of ice clouds increases *PEWV* but it decreases *PEH* on 7 June. On 4 June, the water vapor realted surface rainfall budgets reveal that all rainfall processes contribute to rain rate in C and CNIR (Table 2), which leads to 100% of *PEWV* in the two experiments. The thermally related surface rainfall budgets show that rainfall is associated with heat divergence and radiative cooling in the two experiments (Table 3). Thus, local atmospheric cooling (*SHT*<0) makes PEH less than 100% in the two experiments.



Table 1. (a) *PEWV* and (b) *PEH* calculated data averaged daily and over model domain, convective regions, and raining stratiform regions in C, CNIR, and CNIM. Unit is %.

Thermodynamic Aspects of Precipitation Efficiency 87

*PEWV* and *PEH* on 5 and 6 June. On 7 June, the exclusion of radiative effects of ice clouds increases *PEWV* through the local atmospheric change from moistening in C to drying in CNIR associated with the decrease in water vapor convergence while the two experiments have similar transport rates of hydrometeor concentration from convective regions to raining stratiform regions. The two experiments have similar *PEH* because of similar thermal processes. Note that radiative cooling is negligibly small over convective regions. Over raining stratiform regions, the removal of radiative effects of ice clouds decreases *PEWV* through the enhanced local atmospheric moistening on 4 June. Because the increase in rainfall from C to CNIR is similar to the increase in rainfall source that is from the heat divergence and the transport of hydrometeor concentration from convective regions to raining stratiform regions, the increase in stratiform rainfall from C to CNIR leads to the increase in *PEH*. On 5 June, the elimination of radiative effects of ice clouds decreases *PEWV* because the local water vapor is barely changed in C and the local atmospheric moistening occurs in CNIR. The two experiments have similar *PEH* due to similar rainfall sources from thermal and cloud processes. On 6 June, the exclusion of radiative effects of ice clouds leads to the decreases in *PEWV* through the local atmospheric change from drying in C to moistening in CNIR and reduces *PEH* through the enhanced local atmospheric cooling. On 7 June, the removal of radiative effects of ice clouds increases *PEWV* through the slowdown in water vapor divergence. Because the decrease in rainfall is similar to the decrease in the rainfall source from heat divergence and transport of hydrometeor concentration from convective regions to raining stratiform regions as a result of similar local atmospheric cooling rate in the two experiments, the decrease in stratiform rainfall from C to CNIR leads

to the decrease in *PEH*.

weakened.

**6. Microphysical effects of ice clouds: CNIM versus CNIR** 

The calculations of model domain mean simulation data show the decreases in *PEWV* and *PEH* from CNIR to CNIM during the life span of pre-summer heavy rainfall event (Figs. 9a-10a). On 4 June, the exclusion of microphysical effects of ice clouds decreases *PEWV* and *PEH* through the hydrometeor change from loss in CNIR to gain in CNIM and the weakened local atmospheric cooling (Figs. 11a-17a). On 5 June, the decrease in *PEWV* is associated with the intensification in local atmospheric moistening and the hydrometeor change from loss in CNIR to gain in CNIM. The reduction in *PEH* is related to the hydrometeor change from loss in CNIR to gain in CNIM. On 6 June, the decrease in *PEWV* corresponds to the strengthened hydrometeor gain. *PEH* is barely changed in the two experiments because of similar rates of rainfall source from thermal processes. On 7 June, the decreases in *PEWV* and *PEH* result from the hydrometeor change from loss in CNIR to gain in CNIM although water vapor divergence and local atmospheric cooling are

Over convective regions, *PEWV* and *PEH* are increased from CNIR to CNIM during the life span of pre-summer heavy rainfall event (Figs. 9b-10b). The exclusion of microphysical effects of ice clouds increases *PEWV* and *PEH* through the weakened transport of hydrometeor concentration from convective regions to raining stratiform regions during 4-6 June (Figs. 11b-17b). The decrease in local atmospheric cooling also contributes to the increases in *PEWV* and *PEH* on 6 June. On 7 June, the removal of microphysical effects of ice clouds increases *PEWV* through the weakened transport of hydrometeor concentration from


Table 2. Water vapor related surface rainfall budget (*PSWV*, *QWVT*, *QWVF*, *QWVE*, and *QCM*) averaged daily and over model domain, convective regions, and raining stratiform regions in C, CNIR, and CNIM. Unit is mm h-1.

The removal of radiative effects of ice clouds decreases *PEH* from C to CNIR through the enhanced local atmospheric cooling associated with the enhanced radiative cooling because of similar heat divergence in the two experiments. On 5 June, the elimination of radiative effects of ice clouds increases *PEWV* through the reduced local atmospheric moistening (*QWVT*<0) associated with the decreased water vapor convergence (*QWVF*>0). The two experiments have similar *PEH* because of similar heat related rainfall processes. On 6 June, the exclusion of radiative effects of ice clouds decreases *PEWV* and *PEH* from C to CNIR through the enhanced hydrometeor gain (*QCM*>0) because water vapor and heat processes have similar contributions to rainfall (*QWVT+QWVF+QWVE SHT+SHF+SHS+SLHLF+SRAD*) in the two experiments. On 7 June, the removal of radiative effects of ice clouds increases *PEWV* through the decreased water vapor divergence, whereas it decreases *PEH* through the enhanced local atmospheric cooling associated with the enhanced radiative cooling.

Over convective regions, the exclusion of radiative effects of ice clouds decreases *PEWV* and *PEH* through the intensified transport of hydrometeor concentration from convective regions to raining stratiform regions (*QCM*<0) because water vapor and heat processes have similar contributions to rainfall in the two experiments on 4 June. Similar magnitudes of rainfall sources associated with water vapor, heat, and cloud processes lead to similar

*PSWV* 1.16 1.07 0.92 0.86 0.73 0.80 0.30 0.34 0.13 *QWVT* 0.22 0.19 0.16 0.52 0.46 0.31 -0.06 -0.17 -0.09 *QWVF* 0.87 0.86 0.84 0.57 0.60 0.64 0.09 0.18 0.13 *QWVE* 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 *QCM* 0.05 0.01 -0.09 -0.24 -0.33 -0.16 0.28 0.32 0.09

*PSWV* 1.54 1.59 1.27 0.92 0.99 0.93 0.62 0.59 0.35 *QWVT* -0.13 -0.03 -0.17 0.10 0.35 0.21 0.00 -0.06 0.10 *QWVF* 1.59 1.53 1.55 1.17 1.06 0.93 0.20 0.19 0.13 *QWVE* 0.03 0.04 0.02 0.00 0.01 0.00 0.01 0.02 0.00 *QCM* 0.05 0.04 -0.13 -0.37 -0.42 -0.22 0.41 0.44 0.12

*PSWV* 2.95 2.84 2.69 2.21 2.21 2.36 0.74 0.64 0.32 *QWVT* 0.34 0.41 0.31 0.77 0.92 0.87 0.03 -0.14 0.17 *QWVF* 2.57 2.51 2.62 1.92 1.80 1.83 0.23 0.38 0.03 *QWVE* 0.04 0.04 0.02 0.01 0.01 0.00 0.01 0.02 0.00 *QCM* -0.01 -0.11 -0.26 -0.49 -0.53 -0.34 0.47 0.38 0.12

*PSWV* 0.54 0.51 0.46 0.29 0.33 0.32 0.25 0.19 0.15 *QWVT* 0.64 0.59 0.67 -0.09 0.08 0.08 0.65 0.30 0.19 *QWVF* -0.32 -0.28 -0.23 0.52 0.39 0.32 -0.63 -0.32 -0.14 *QWVE* 0.16 0.17 0.10 0.01 0.01 0.00 0.02 0.04 0.01 *QCM* 0.05 0.03 -0.08 -0.15 -0.16 -0.09 0.20 0.17 0.09

Table 2. Water vapor related surface rainfall budget (*PSWV*, *QWVT*, *QWVF*, *QWVE*, and *QCM*) averaged daily and over model domain, convective regions, and raining stratiform regions

enhanced local atmospheric cooling associated with the enhanced radiative cooling.

Over convective regions, the exclusion of radiative effects of ice clouds decreases *PEWV* and *PEH* through the intensified transport of hydrometeor concentration from convective regions to raining stratiform regions (*QCM*<0) because water vapor and heat processes have similar contributions to rainfall in the two experiments on 4 June. Similar magnitudes of rainfall sources associated with water vapor, heat, and cloud processes lead to similar

The removal of radiative effects of ice clouds decreases *PEH* from C to CNIR through the enhanced local atmospheric cooling associated with the enhanced radiative cooling because of similar heat divergence in the two experiments. On 5 June, the elimination of radiative effects of ice clouds increases *PEWV* through the reduced local atmospheric moistening (*QWVT*<0) associated with the decreased water vapor convergence (*QWVF*>0). The two experiments have similar *PEH* because of similar heat related rainfall processes. On 6 June, the exclusion of radiative effects of ice clouds decreases *PEWV* and *PEH* from C to CNIR through the enhanced hydrometeor gain (*QCM*>0) because water vapor and heat processes have similar contributions to rainfall (*QWVT+QWVF+QWVE SHT+SHF+SHS+SLHLF+SRAD*) in the two experiments. On 7 June, the removal of radiative effects of ice clouds increases *PEWV* through the decreased water vapor divergence, whereas it decreases *PEH* through the

4 June

5 June

6 June

7 June

in C, CNIR, and CNIM. Unit is mm h-1.

Model domain mean Convective regions Raining stratiform

C CNIR CNIM C CNIR CNIM C CNIR CNIM

regions

*PEWV* and *PEH* on 5 and 6 June. On 7 June, the exclusion of radiative effects of ice clouds increases *PEWV* through the local atmospheric change from moistening in C to drying in CNIR associated with the decrease in water vapor convergence while the two experiments have similar transport rates of hydrometeor concentration from convective regions to raining stratiform regions. The two experiments have similar *PEH* because of similar thermal processes. Note that radiative cooling is negligibly small over convective regions. Over raining stratiform regions, the removal of radiative effects of ice clouds decreases *PEWV* through the enhanced local atmospheric moistening on 4 June. Because the increase in rainfall from C to CNIR is similar to the increase in rainfall source that is from the heat divergence and the transport of hydrometeor concentration from convective regions to raining stratiform regions, the increase in stratiform rainfall from C to CNIR leads to the increase in *PEH*. On 5 June, the elimination of radiative effects of ice clouds decreases *PEWV* because the local water vapor is barely changed in C and the local atmospheric moistening occurs in CNIR. The two experiments have similar *PEH* due to similar rainfall sources from thermal and cloud processes. On 6 June, the exclusion of radiative effects of ice clouds leads to the decreases in *PEWV* through the local atmospheric change from drying in C to moistening in CNIR and reduces *PEH* through the enhanced local atmospheric cooling. On 7 June, the removal of radiative effects of ice clouds increases *PEWV* through the slowdown in water vapor divergence. Because the decrease in rainfall is similar to the decrease in the rainfall source from heat divergence and transport of hydrometeor concentration from convective regions to raining stratiform regions as a result of similar local atmospheric cooling rate in the two experiments, the decrease in stratiform rainfall from C to CNIR leads to the decrease in *PEH*.
