Research aircraft HALO: New insights into the climate of the Southern Ocean!

Research aircraft HALO: New insights into the climate of the Southern Ocean!

The HALO research aircraft, used for important atmospheric and climate studies, will embark on a significant mission over the Southern Ocean in September 2025. The mission, known as HALO-South, will take place from early September to mid-October 2025 and will focus on studying cloud conditions in this unique region. Loud DLR The research fleet will operate from Christchurch, New Zealand and will complete approximately 176 flight hours over the five weeks.

A central point of the HALO South mission is the goal of closing knowledge gaps in climate models. The interaction between clouds, aerosols and radiation is examined in order to improve our understanding of atmospheric conditions. A fascinating discovery could result from this: In the region around Antarctica, the atmosphere is particularly clean, which is characteristic of conditions with lower emissions.

Technological equipment

HALO has various state-of-the-art instruments available for comprehensive measurements. The most important measuring probes include the PCASP-100X (Passive Cavity Aerosol Spectrometer Probe) and the PIP probe (Precipitation Imaging Probe). While the PCASP-100X examines aerosol size distributions in the range of 0.12 to 3.5 micrometers, the PIP probe images cloud particles between 100 and 6,400 micrometers. The mission is also supported by data from the Japanese weather satellite HIMAWARI-9, which provides classifications for cloud types.

The research mission is part of a larger international project in which around 50 scientists from different institutions are involved. Loud HALO Research The measurements also include carbon monoxide, nitrogen oxides, methane and ozone. These and other measurements such as aerosol size distributions, particle volatility and properties of cloud condensation nuclei will provide valuable data for climate research.

The most important measuring instruments

The instruments used include:

• SMART-Albedometer, das die spektrale Strahlungsintensität im Bereich von 350-2200 nm misst.
• DLR-intern entwickelte Geräte wie das AMTEX-2 zur Messung von NO, NOy, und das SOPAMA zur Analyse von schwarzen Kohlenstoffpartikeln.
• Forschungseinrichtungen wie TROPOS leisten mit unterschiedlichsten Geräten, wie dem miniCCNC, ebenfalls wertvolle Beiträge zur Messung von Aerosoleigenschaften.
• Zusätzlich wird die Anzahl der Eiskeime parallel zu Wolkenpartikeln erstmals erfasst, was einen innovativen Ansatz darstellt, die Wechselwirkungen in der Atmosphäre besser zu verstehen.

The first measurement flights are planned for the second week of September 2025, while the HALO research aircraft will be converted for use by the end of August. Experts fear that in the southern hemisphere, where there are fewer particles, there will also be less cloud formation. This could have significant impacts on climate developments in this region.

Overall, the HALO South mission promises to provide promising insights into climate research by focusing on aspects that have so far been insufficiently investigated. The combination of advanced technology and international cooperation is a crucial factor in deepening our understanding of the influence of human activities on the climate.