Laser Research Launches to Explore Aerosol Impact on Climate

A research initiative focusing on the atmospheric impact of aerosols has commenced at the MetService site near Invercargill Airport in New Zealand. The project, named goSouth-2, is a collaborative effort between German and New Zealand institutions, aiming to deepen understanding of how aerosols influence climate and weather patterns.

The German collaborators include the Meteorological Institute of the University of Leipzig and the Leibniz Institute for Tropospheric Research (TROPOS), while New Zealand partners consist of MetService, the University of Canterbury, and The Air Quality Collective. On-site preparations are currently underway, with five staff members from TROPOS setting up equipment in anticipation of the project’s official launch on September 3, 2023.

Researchers, including Dr. Patric Seifert from TROPOS, emphasize the significance of aerosols—tiny airborne particles that originate from various natural and anthropogenic sources such as sea salt, dust, pollen, and smoke. These particles play a crucial role in cloud formation by serving as nuclei for moisture to condense upon. Dr. Seifert stated, “The less aerosol particles are available, the less cloud particles can form, and vice-versa.”

The geographical location of Invercargill, situated at the northern edge of the Southern Ocean, provides a unique setting for this research. Dr. Seifert noted that the atmosphere in this region can be exceptionally clean when air masses flow in from Antarctica. Conversely, the arrival of continental air masses from Australia results in higher aerosol concentrations. By studying these variations, researchers aim to enhance their understanding of how clouds respond to differing aerosol levels.

Addressing Gaps in Climate Models

Current atmospheric and climate models exhibit less accuracy in predicting cloud behavior over the Southern Ocean compared to the northern hemisphere. Dr. Seifert mentioned that the discrepancies may stem from the differences in aerosol levels between the two hemispheres. The northern hemisphere tends to have more data available due to its higher pollution levels, leaving gaps in understanding for the southern hemisphere.

Invercargill’s suitability for this research extends beyond its unique atmospheric conditions. The area offers logistical support for operating equipment and accommodating researchers. MetService has already established a comprehensive observational framework at the site, including long-term records of weather balloon soundings, precipitation measurements, and data on solar and thermal radiation.

The project utilizes land-based instruments, but residents in the vicinity may observe a green laser beam in the sky, which is part of the lidar (light detection and ranging) systems used to study aerosols. Dr. Seifert confirmed that the airport staff have been informed about the laser’s presence, ensuring safety protocols are in place. Additionally, radar systems will be employed to monitor and analyze cloud formations and precipitation patterns.

TROPOS personnel will remain on-site for a duration of 18 months, while a team of approximately 15 researchers in Germany will be involved in data analysis. This initiative builds on the previous goSouth-1 study conducted in 2022 at Pahia, located 50 kilometers from Invercargill, which provided foundational insights using more limited equipment.

Through the efforts of the goSouth-2 project, scientists aim to bridge existing gaps in climate research, enhance atmospheric models, and ultimately contribute to a better understanding of the relationship between aerosols and climate systems.