Contrail Formation in Southeastern Michigan with Potential Regional and Global Impacts

Abstract:

This research attempted to determine the extent to which contrails formed by planes flying at high altitudes are affected by the presence or absence of large bodies of water such as the Great Lakes. Contrails are anthropogenic clouds that appear as streaks in the sky following the condensation of aircraft engine exhaust on aerosols at the cold, higher altitudes found in the atmosphere where many aircraft fly. Near daily cloud observations from August 2019 through February 2019 were made using GLOBE Cloud protocols and then the data was uploaded to GLOBE via the NASA-GLOBE Cloud Observer App and/or through direct data entry. This data was then compared with NASA satellite images using the information emailed to the researchers from LaRC-GLOBE-Clouds@mail.nasa.gov. Crestwood High School contrail data was then analyzed with data that other schools uploaded using the GLOBE Visualization System. The analyzed data showed that contrail formation was strongly correlated with cold upper altitude temperatures (as shown in satellite images). Upper-level temperatures also affected the number of contrails observed from the ground. Additionally, some sites along the northern portion of Lake Michigan reported a relatively large number of persistent contrails supporting the role that water vapor availability in the atmosphere plays in possible contrail formation. The ability to further match cloud observations from other locations around the Great Lakes was hampered by inconsistent reporting by other GLOBE observers. Future research will include global collaboration with a partnering school in Thailand. Scientists are still evaluating the impacts that contrails, particularly persistent contrails that remain in the sky for prolonged periods of time, have on local and global climates. This and future GLOBE ground-based cloud research will help to form a solid database that NASA and other scientists can use to unravel the potential implications and effects of contrails on climate change.