BAIRS II: The Second Buffalo Area Icing and Radar Study

BAIRS II: The Second Buffalo Area Icing and Radar Study*

The second Buffalo Area Icing and Radar Study (BAIRS II) field campaign occurred during the winter of
2017 through a partnership of the National Research Council of Canada, Environment and Climate
Change Canada, and the Massachusetts Institute of Technology Lincoln Laboratory (MIT LL). BAIRS II in
situ microphysical data were collected to support continued development of a NEXRAD dual‐polarimetric-based
icing hazard detection algorithm for the U.S. Federal Aviation Administration. The suite of
collected data makes possible additional icing hazard verification and NEXRAD hydrometeor
classification algorithm (HCA) validation that started with the original 2013 BAIRS field campaign. BAIRS
II and BAIRS are the only campaigns focused on icing with in situ probing specifically guided by
operational NEXRAD dual polarization and hydrometeor classification data.

A first‐version of the icing hazard levels (IHL) algorithm product is deployed in NEXRAD’s operational
baseline. It identifies icing hazard regions through a combined interpretation of the graupel HCA class
with meteorological model data. It has been validated against icing pilot reports and original BAIRS
data. The BAIRS II science objectives focus on the in situ probing of non‐graupel‐related radar features
signaling an icing hazard. Automated detection (no human‐in‐the‐loop) of those features will be added
to a future version of IHL to expand the radar‐based icing hazard coverage. A description of the
missions will be provided. Examples will be discussed that connect the science objectives to the
campaign successes and relate them to a future IHL algorithm.

*DISTRIBUTION STATEMENT A. Approved for public release: distribution unlimited. This material is based upon
work supported by the Federal Aviation Administration under Air Force Contract No. FA8721‐05‐C‐0002 and/or
FA8702‐15‐D‐0001. Any opinions, findings, conclusions or recommendations expressed in this material are those of
the author(s) and do not necessarily reflect the views of the Federal Aviation Administration.