CAESAR

Cold Air Outbreak Experiment in the Sub-Arctic Region

PROJECT DATES
02/22/2024 - 04/07/2024
Project Location
Kiruna, Sweden
PROJECT DESCRIPTION

CAESAR Field Program Logo

One of Earth's most intense air mass transformations happens when cold Arctic air flows out over the much warmer open oceans in so-called Cold-Air Outbreaks (CAOs). The surface heat fluxes are among the highest observed on Earth, supporting highly convective clouds capable of producing heavy snowfall and occasionally spawning intense "polar lows." Surprisingly little is known about their Lagrangian evolution, the relationship between up- and downstream conditions, and between the surface fluxes, boundary-layer structure, cloud and precipitation properties, and mesoscale circulations. These clouds provide a powerful modeling test bed for improving the representation of mixed-phase cloud processes in large eddy simulations, numerical weather prediction, and global climate models. 

Thus, the PI team proposes a dedicated field campaign, Cold Air Outbreak Experiment in the Sub-Arctic Region (CAESAR), to examine the structure of marine boundary layer clouds during CAOs. CAESAR will deploy the NSF/NCAR C-130 aircraft, with in situ and remote sensors sampling Arctic air masses from the CAO origin at the ice edge throughout their transformation downstream. A rich array of airborne radars and lidars, aerosol, cloud, precipitation, and trace gas probes, deployed during CAO events over the open waters between northern Sweden and the Arctic ice edge for 45 days in early 2024, will provide a detailed characterization that will form the backbone of modeling studies across a range of scales and form a long-lasting legacy dataset.

CONTACT INFORMATION

Scientific Steering Committee:

Paquita Zuidema, University of Miami

Bart Geerts, University of Wyoming

Greg McFarquhar, University of Oklahoma

Investigators (listed alphabetically)

Adriana Bailey - U of Michigan

Paul DeMott/Russell Perkins - CSU

Jim Doyle - NRL

Jeff French - U of Wyoming

Markus Petters/Jefferson Snider - NCSU/U of Wyoming

Yonggang Wang - SUNY-Oswego

Zhien Wang/John Cassano - SUNY-Stonybrook/U of Colorado

Project Manager

Cory Wolff, NCAR/EOL/RAF

To be added to the CAESAR Ops Email List, please contact Cory Wolff.

Data Manager

EOL Archive NCAR/EOL/DMS