By Chrysandra Medley
In June, the U.S. Department of Energy (DOE) announced $15 million in funding for 27 projects in atmospheric and ecological sciences in an effort to improve Earth systems models and better predict weather and climate. One of these projects includes AOSC-ESSIC professor Zhanqing Li’s research, “Investigation of the surface coupling of marine clouds and its interactions with aerosols over the Southern Ocean”.
The grant will utilize Atmospheric Radiation Measurement (ARM) data (from the Measurements of Aerosols, Radiation, and Clouds Over the Southern Ocean (MARCUS) campaign) along with large eddy simulation modeling to look at the dynamic coupling of clouds, aerosols, and the ocean surface in the Southern Ocean marine boundary layer.
Using a combination of data analysis and observation, the team hopes to gain a better overall understanding of cloud behavior, including how aerosols affect cloud heat exchange processes (warming).
“In principal, aerosols have two broad effects on the Earth’s climate by interacting with radiation and clouds to alter the earth’s energy and water cycles. Depending on their loading and properties, the two effects may work coherently or against each other, making it one of the most challenging problem in climate science,” said Li.
The newly funded study is a continuation of similar research that Li and his team began almost a decade ago in China where aerosol loading is much high due to intensive human activities that have drastically altered the environment and climate in the region, as found by the team.
“Clouds respond to aerosols in a dramatically different ways in polluted and pristine conditions. While the polluted clouds have been studied extensively, their clean counterparts have not,” said Youtong Zheng, a member of Li’s research team and post-doctoral associate at ESSIC.
Conversely, the air above the Southern Ocean is pure and unpolluted, free from the types of human activity that create pollution. The pristine environment provides the team with a unique opportunity to quantify how unaltered clouds respond to aerosols.
The team believes that clouds in the clean Southern Ocean environment are more likely to decouple from the ocean surface due to warm air masses travelling above cold sea surfaces, which frequently occurs in the Southern Ocean. Decoupling is when the moisture from the sea surface is cut, affecting the clouds’ moisture supply. This could affect the transport of aerosols to the cloud layer, as well as alter other cloud properties.
The project could have huge implications for future climate modeling and understanding of clouds.
“With this improved understanding, we could better represent [cloud-aerosol interaction] in climate models and have a more accurate prediction of our climate,” said Zheng.
Zhanqing Li is an AOSC-ESSIC professor who has engaged in a wide range of studies concerning climate change, atmospheric physics, and the terrestrial and atmospheric environment. He is deeply engaged in the cloud absorption anomaly debate, systematically studied China’s environmental and climate problems, and investigated aerosol properties and their direct and indirect effects. In 2008, he received a DOE grant for a similar project entitled, “Use of ARM Mobile Facility (AMF) Data to Study Aerosol Indirect Effects in China”.