Motivation

The "Changma," the annual summer rainy season, has long been a familiar meteorological phenomenon in South Korea. However, we have recently been witnessing abnormal climate events such as heavy rains and landslides. Specifically, this summer of 2025, we experienced not a typical prolonged rainy season, but an on-and-off rain pattern that included record-breaking torrential rains. This shift from "rainy season" to "unpredictable extreme weather" has left many of us confused and anxious. We realized that the Changma is no longer just a seasonal inconvenience; it has evolved into an unidentifiable and dangerous system.

We are led to ask one question:

"Is Changma Precipitation becoming More Extreme due to Climate Change?"

Our Goal

This project begins with this question.

We aim to investigate the specific impacts of climate change on the Changma system of the Korean Peninsula.

The primary goal of this project is to predict the changes in the Changma resulting from climate change.

Objectives

To achieve this, we have established the following specific objectives:

Understanding the Changma

To investigate the fundamental background knowledge of the Changma, including its definition, characteristics, and formation processes.

Dynamic Factors of the Changma

To study the dynamical principles involved in the formation process of the Changma.

Predicting the Future of Changma

To find out how climate change will alter the Changma.

Methods & Data

Fundamental Equations and Components

Changma Analysis Basis:

Atmospheric Dynamics Equations: Continuity Eq, Moisture Flux Eq, Moisture Budget Eq

Climate Change Assessment Variables:

Thermodynamic Component: humidity (moisture availability)
Dynamic Component: wind, specifically Western North Pacific Subtropical High (WNPSH)

Data Sources and Modeling

Our research applied a secondary research method, utilizing data obtained from established sources:

Observational Data: Hourly rainfall data collected by Automated Synoptic Observing System (ASOS), from Korea Meteorological Administration (KMA)
Climate Modeling: Convection-Permitting Model (CPM) to project changes in Changma precipitation

*CPM: type of high-resolution regional climate model with improved performance in simulating short-duration extreme rainfall events