DOI: 10.5281/zenodo.18374164
title: Data for publication 'Inferring the Controlling Factors of Ice Aggregation from Targeted Cloud Seeding Experiments'

description: # Data for publication 'Inferring the Controlling Factors of Ice Aggregation from Targeted Cloud Seeding Experiments'


> **Authors:** Huiying Zhang , Fabiola Ramelli, Christopher Fuchs , Nadja Omanovic , Anna J. Miller , Robert Spirig, Zhaolong Wu , Yunpei Chu , Xia Li, Ulrike Lohmann , and Jan Henneberger

> **Affiliation:** ETH Zurich

> **Contact:** huiying.zhang@env.ethz.ch


## 📄 Overview


This repository contains post-processed cloud microphysics measurements from the **CLOUDLAB 2023** campaign.

The dataset focuses on ice crystal properties, aggregation processes, riming and irregularity diagnostics, and associated environmental and dynamical conditions.


All time-resolved statistics are recorded at **1-second resolution**, where each row represents an aggregated observation at a specific second within a given experiment (`time_label`).


---


## 📂 Repository Structure


```text

.

├── README.md

├── cloudlab2023_ice_properties_postprocessed.csv

├── merged_with_edr_postprocessed.csv

├── merged_with_edr_irregular_postprocessed.csv

└── merged_with_edr_rimed_postprocessed.csv

````


---


## 📑 File Descriptions


### 1️⃣ `cloudlab2023_ice_properties_postprocessed.csv`


**Particle-level ice crystal properties**


* Contains **individual ice crystal measurements** derived from image-based processing.

* Each row corresponds to **one detected ice particle**.

* Includes detailed geometric, morphological, and texture-related descriptors (e.g. size, aspect ratio, perimeter statistics, phase-related features).

* Intended for **particle-scale analysis** or custom re-aggregation.


⚠️ **Note**

This file is **not second-averaged** and is generally **not required** for bulk microphysical or aggregation-rate analysis unless particle-level diagnostics are needed.


**Key identifiers**


* `time_id`

* `time_label`

* `class` (e.g. `Column_aged`)

* `num_objects`


---


### 2️⃣ `merged_with_edr_postprocessed.csv`


**Core second-level microphysics dataset (recommended main file)**


* Second-averaged statistics aggregated from particle-level measurements

* Merged with turbulence (EDR) and environmental variables

* This is the **primary dataset** for most analyses


Each row represents **one second within one experiment**.


---


### 3️⃣ `merged_with_edr_irregular_postprocessed.csv`


**Second-level dataset with irregular ice diagnostics**


* Extension of `merged_with_edr_postprocessed.csv`

* Includes diagnostics related to **irregular ice monomers**


**Additional variables**


* `irregular_monomers`: Number of irregular monomers

* `irregular_ice_count`: Number of ice particles containing at least one irregular monomer


---


### 4️⃣ `merged_with_edr_rimed_postprocessed.csv`


**Second-level dataset with riming diagnostics**


* Extension of `merged_with_edr_postprocessed.csv`

* Includes statistics related to rimed ice particles


**Additional variables**


* `rimed_monomers`: Number of rimed monomers

* `rimed_ice_count`: Number of ice particles containing at least one rimed monomer


---


## 🔑 Key Variables (Second-Level Files)


### ⏱ Identifiers & Time


* `time`: Observation timestamp (1-second resolution)

* `time_label`: Experiment label (e.g. `SM048`)

* `Time_gps`: GPS time


---


### ❄️ Ice Crystal Properties


* `avg_ice`: Mean ice crystal number

* `num_ice_original`: Initial ice crystal count (at seeding time)

* `num_agg_events`: Number of ice aggregation events

* `asprat_mean`: Mean aspect ratio

* `majsiz_mean`: Mean major-axis length (m)

* `majsiz_std`: Standard deviation of major-axis length

* `majsiz_large_fraction`: Fraction of crystals larger than 200 μm

* `majsiz_cov`: Coefficient of variation of major-axis length

* `ice_volume`: Total ice volume (cm³)

* `ice_con`: Ice crystal number concentration (cm⁻³)


---


### 💧 Water-Related Properties


* `water_content`: Cloud water content (g m⁻³)

* `water_meanD`: Mean droplet diameter (m)

* `water_concentration`: Droplet number concentration (cm⁻³)

* `background_water_concentration`: Background droplet concentration (cm⁻³)

* `background_water_content`: Background liquid water content (g m⁻³)


---


### 🌡 Environmental & Dynamical Conditions


* `resi_time_remsens_s`: Residence time from seeding to measurement site (s)

* `seed_distance`: Distance between seeding and measurement sites (m)

* `seed_temp_degC`: Ambient temperature (°C)

* `ICNC_origin`: Initial ice crystal number concentration (cm⁻³)

* `R_agg`: Ice aggregation rate (cm⁻³ s⁻¹)

* `EDR (m^2 s^-3)`: Eddy Dissipation Rate (turbulence intensity)


---


## 📌 Usage Recommendations


* **General microphysics & aggregation analysis**

→ `merged_with_edr_postprocessed.csv`


* **Irregularity-related studies**

→ `merged_with_edr_irregular_postprocessed.csv`


* **Riming-related studies**

→ `merged_with_edr_rimed_postprocessed.csv`


* **Particle-level morphology analysis**

→ `cloudlab2023_ice_properties_postprocessed.csv`


---


## 📎 Notes


* All number concentrations are reported in **cm⁻³** unless otherwise stated.

* Aggregation rates are reported in **cm⁻³ s⁻¹**.

* Variable names are kept consistent across second-level files to facilitate comparison.


---


## 📬 Contact


For questions regarding data processing or usage, please contact the dataset author.


```