We study
Extreme weather and climate events such as hurricanes, heatwaves, flooding, and droughts cause tremendous societal, economic, and environmental losses all over the globe each year; one cannot overemphasize the importance of accurate weather and climate prediction. Our ability to forecast high-impact weather and climate events heavily rely on the quality of the computer programs that numerically solve the governing equations of the atmospheric and oceanic circulations, and of their interactions with the other components of the Earth system. Moist convection in the tropics plays a vital role in the Earth system as the heat engine of the large-scale atmospheric circulation and by modulating the water and energy cycles across the globe.
We are a research group who studies moist convection and large-scale variability in the tropics to improve their representation in the weather and climate forecast models. Besides their chaotic nature, cumulus clouds in the tropics organize at various spatial scales by means of interactions with circulation, surface flux, moisture, and radiation. Those emergent patterns of tropical convection have long been poorly represented in many weather and climate models, weakening their predictive capability. We are developing a systematic understanding of different types of organized tropical convection and identifying sources of model errors in simulating them. In doing so, we are taking part in the efforts to making predictions of future extreme weather and climate events more accurate.
Dynamics, modeling, and prediction of the Madden-Julian oscillation and its teleconnections
Madden-Julian Oscillation (MJO) is the dominant tropical intraseasonal variability that influences the global weather-climate-environment system. Despite that the MJO was discovered nearly five decades ago, fundamental questions about its nature have remained unanswered and it is poorly represented in many weather and climate models. With the goals of advancing our understanding and improving model representations of the MJO, we have looked at diverse types of observations to better understand the MJO’s behaviors (Kim et al. 2014b; Kim et al. 2017; Kang et al. 2020), developed a theoretical model of the MJO (Adames and Kim 2016), analyzed climate model simulations of current and future climates to evaluate model fidelity (Ahn et al. 2017; Ahn et al. 2020) and to understand MJO’s changes in the future climate (Adames et al. 2017, 2018; Rushley et al. 2018), and developed the process-oriented diagnostics for MJO simulation (Kim et al. 2014a; Kim et al. 2015). Our research has collectively demonstrated that the MJO can be understood as a moisture mode, a special type of wave in the tropics whose propagation and maintenance are explained by those of moisture in the columns of the atmosphere.
Moist thermodynamics of tropical cyclogenesis and tropical cyclone intensification in observations and in high-resolution global models
The objective of our TC research is to understand the key processes associated with TC genesis and intensification in model simulations as well as in observations.
Mechanism of mesoscale convective organization and its representation in global models
Despite its ubiquitous presence and critical roles in the Earth system, the mesoscale organized deep convection on the scale of ~10-100 km is not properly represented in most climate models and the mechanism through which individual cumulus clouds aggregate has not been fully understood.