2026-10-06T09:26:19Z https://api.figshare.com/v2/oai

oai:figshare.com:article/33971869 2026-09-28T09:59:26Z category_25729 category_25741 item_type_3 month_year_09_2026

<b>Impacts of cloud droplet identification criteria on aerosol-cloud interactions: A simulation study using the adiabatic cloud parcel model</b> yao jing ting (25077136) Atmospheric aerosols Cloud physics aerosol-cloud interaction cloud condensation nuclei activation adiabatic parcel model <p dir="ltr">Fixed cloud droplet identification criteria are widely adopted in aerosol–cloud interaction (ACI) analyses, though systematic biases introduced by this simplified treatment remain poorly constrained. This study employes an adiabatic cloud parcel model to investigate the modulation of ACI quantification by different cloud droplet identification criteria. Two representative schemes are examined: a dynamically varying critical radius (<i>R</i>_<em>c</em>) derived from Köhler theory, and a fixed critical radius (<i>R</i>_<em>c</em>_<em>,</em>_<em>f</em>₎ of 1 μm that has been widely adopted in previous studies. At the height of maximum supersaturation (<i>SS</i>_<em>max</em>) within cloud profile, the Köhler-based criterion producesa monotonic growth in cloud droplet number concentration (<i>N</i>_<em>c</em>) with rising aerosol number concentration (<i>N</i>_<em>a</em>) and updraft velocity (<i>w</i>), consistent with classical Twomey effect. By contrast, the fixed threshold generates pronounced artificial anomalies, including an anti-Twomey effect under high aerosol loading and reduced <i>N</i>_<em>c</em> under intensified<i> </i><i>w</i> for highly hygroscopic aerosols. These anomalies represent statistical artifacts, as newly activated droplets fail to grow beyond 1 μm at the <i>SS</i>_<em>max</em> height due to limited condensational growth. The two criteria produce substantially divergent cloud sensitivity estimates near the <i>SS</i>_<em>max</em> level: the fixed threshold overestimates cloud sensitivity under weak updrafts and markedly underestimates cloud sensitivity under strong updrafts. These discrepancies diminish significantly approximately 100 m above the SSmax level owing to sustained droplet condensational growth. The results demonstrate that fixed size thresholds introduce height-dependent biases in ACI quantification. Explicit consideration of droplet growth evolution and sampling altitude is therefore essential for robust characterization and interpretation of aerosol-modulated cloud variations.</p> 2026-09-28T09:59:26Z Dataset Dataset 10.6084/m9.figshare.33971869.v1 https://figshare.com/articles/dataset/_b_Impacts_of_cloud_droplet_identification_criteria_on_aerosol-cloud_interactions_A_simulation_study_using_the_adiabatic_cloud_parcel_model_b_/33971869 CC BY 4.0