Laser Research Project Launches to Examine Aerosols in Atmosphere

A new atmospheric research project using lasers has been initiated at the MetService site near Invercargill Airport, New Zealand. The project, known as goSouth-2, aims to gather critical data on how aerosols—tiny airborne particles—affect the atmosphere. This collaborative effort involves institutions from both Germany and New Zealand, including the Meteorological Institute of the University of Leipzig and the Leibniz Institute for Tropospheric Research (TROPOS), along with New Zealand’s MetService, the University of Canterbury, and The Air Quality Collective.

On September 3, 2023, the project will officially commence with five TROPOS researchers setting up essential equipment at the Invercargill site. According to Patric Seifert, a researcher with TROPOS, aerosols come from various sources, including the sea and land, and can include substances like salt, dust, pollen, and smoke particles from natural events such as volcanic eruptions.

Understanding Aerosols and Cloud Formation

Dr. Seifert emphasized the crucial role of aerosols in cloud formation. These particles act as nuclei for cloud droplets to form around. “The less aerosol particles are available, the less cloud particles can form, and vice-versa,” he stated. This unique research location at the southern tip of New Zealand allows scientists to study the atmospheric conditions influenced by contrasting air masses. When air approaches from the Antarctic, the atmosphere can be exceptionally clean, whereas air masses from Australia can bring higher levels of aerosols.

The project aims to investigate how variations in aerosol levels impact cloud formation and behavior. Dr. Seifert pointed out that atmospheric and climate models have traditionally struggled to accurately simulate clouds over the Southern Ocean compared to the northern hemisphere. He believes the disparity in aerosol levels between the two hemispheres may be a significant factor in this discrepancy. Data collection in the northern hemisphere has been more extensive, revealing a more polluted atmosphere.

Research Equipment and Community Involvement

Invercargill was selected for its logistical support, which facilitates the operation of equipment and accommodation for staff. The MetService has already conducted vital observations at the site, including long-term weather balloon soundings, precipitation measurements, and solar and thermal radiation assessments. While the majority of the information-gathering instruments will be land-based, residents near Invercargill Airport may notice a green laser beam in the sky as part of the research.

“Our lidar [light detection and ranging] systems emit laser pulses to investigate the aerosols,” Dr. Seifert explained. The laser beam is fixed in position, and airport personnel have been informed about its presence. In addition to lidar, radar systems will also be employed to detect and analyze clouds and precipitation. The TROPOS team will remain on-site for 18 months, while a group of approximately 15 researchers will analyze the collected data in Germany.

Previously, in 2022, the goSouth-1 project was conducted about 50 kilometers from Invercargill, albeit with less equipment and for a shorter duration. This new phase promises to deepen understanding of aerosol impacts on atmospheric dynamics and cloud formation, contributing valuable insights to the field of atmospheric sciences.