Warm-Air Advection Over Melting Sea-Ice: A Lagrangian Case Study

• Published in: Boundary-Layer Meteorology
• Main Authors: You, Cheng, Tjernström, Michael, Devasthale, Abhay
• Other Authors: Stockholm University
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Science and Business Media LLC 2020
• Subjects: Atmospheric Science; Arctic; Sea ice
• Online Access: http://dx.doi.org/10.1007/s10546-020-00590-1; http://link.springer.com/content/pdf/10.1007/s10546-020-00590-1.pdf; http://link.springer.com/article/10.1007/s10546-020-00590-1/fulltext.html

Abstract Observations from the 2014 Arctic Clouds in Summer Experiment indicate that, in summer, warm-air advection over melting sea-ice results in a strong surface melting feedback forced by a very strong surface-based temperature inversion and fog formation exerting additional heat flux on the surface. Here, we analyze this case further using a combination of reanalysis dataset and satellite products in a Lagrangian framework, thereby extending the view spatially from the local icebreaker observations into a Langrangian perspective. The results confirm that warm-air advection induces a positive net surface-energy-budget anomaly, exerting positive longwave radiation and turbulent heat flux on the surface. Additionally, as warm and moist air penetrates farther into the Arctic, cloud-top cooling and surface mixing eventually erode the surface inversion downstream. The initial surface inversion splits into two elevated inversions while the air columns below the elevated inversions transform into well-mixed layers.