What they discover will be used to improve climate models, which routinely underestimate how much solar energy bounces off clouds in that region. Simulating how much solar energy is absorbed or reflected on Earth is key to calculating the future of the planet under climate change.

The Southern Ocean Clouds, Radiation, Aerosol Transport Experimental Study, or , could also help scientists understand the very nature of how clouds interact with aerosols 鈥� natural or human-made particles that are suspended in the atmosphere. Aerosols can cause clouds to form, change their structure and affect precipitation, all of which affect the amount of energy that reaches the surface.

During the mission, which runs from mid-January through Feb. 25, the scientists are collecting data from air and sea. Observations are being taken from the High-performance Instrumented Airborne Platform for Environmental Research, or HIAPER, a operated by the NSF and the National Center for Atmospheric Research, and the , an Australian deep-ocean research vessel.

“Much of what we currently know about Southern Ocean cloud, aerosol and precipitation properties comes from satellite-based estimates, which are uncertain, and have undergone few comparisons against independent data,” said team member , a 91探花research associate professor of atmospheric sciences. 鈥淭he data collected during SOCRATES will also enable us to evaluate current satellite data over the Southern Ocean, as well as potentially help in the design of better satellite-based techniques.鈥�

The research aircraft based out of Hobart, Tasmania, will make about 16 flights over the Southern Ocean. Instruments will measure the size and distribution of cloud droplets, ice crystals and aerosols. The data will help test the theory that climate models may not be producing enough water 鈥� droplets that stay liquid even when the temperature is below freezing.

Measurements will also provide a look back in time to see how the atmosphere behaved in a time when it contained fewer human pollutants.

“It can be difficult to find truly pristine conditions in the Northern Hemisphere,鈥� said , a 91探花professor of atmospheric sciences. 鈥淏y studying the more pristine Southern Ocean region, we hope to be able to learn about what conditions may have been like in the Northern Hemisphere in the pre-industrial period.”

The measurements taken from the sky will be complemented by data collected from the R/V Investigator. 聽The ship’s team will launch soundings every six hours, and sometimes more often, throughout the campaign.

The U.S. portion of SOCRATES is largely funded by the National Science Foundation.

鈥淭he Southern Ocean is famously remote and stormy and it’s hard to imagine a worse place to do a field campaign. But a vast, stormy ocean is a great laboratory for studying clouds, and it’s clear from our models that we have a lot to learn about them,鈥� said Eric DeWeaver, program director in NSF鈥檚 geoscience directorate.

SOCRATES investigators will also incorporate other ocean measurements and data from that 91探花scientists installed in 2016.

“SOCRATES will allow for some of the best observations of clouds, aerosols, radiation, and precipitation that have ever been collected over the Southern Ocean,” said principal investigator , at the University of Oklahoma. “These data will provide us with critical insight into the physics of cloud formation in the region, information we can use to improve global climate models.”

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Based on a National Center for Atmospheric Research . For more information, contact Marchand at rojmarch@uw.edu.

The vast Southern Ocean circling Antarctica soaks up a large portion of the carbon emissions taken up by the oceans and stores some of the extra heat trapped by the carbon emissions that remain in the air. Clouds play a key role, influencing the transfer of heat and light to the surface, but knowledge of these clouds’ properties and their impacts on the surface is hazy.

A 91探花 atmospheric scientist is leading a project to study the clouds above the Southern Ocean. Seeing how the cloud droplets, small bits of dust, sea spray, and other materials on which cloud droplets form, and the ocean and sun interact will help improve global climate models.

, a 91探花research associate professor of atmospheric sciences, is leading the 2-year project sponsored by the Department of Energy. The Macquarie Island Cloud and Radiation Experiment, or , will collect new data for clouds and precipitation in the southernmost seas. The instruments were installed on the island in late March, and are now beginning to collect data.

“We want to study the properties of the clouds, aerosols and precipitation over the remote Southern Ocean, and there are very few land sites where we can take continuous measurements for two years,” Marchand said. “Macquarie is one such place, and is ideal in several respects.”

The instruments, provided by the U.S. Department of Energy’s Climate Research Facility, will measure variables such as surface precipitation, solar energy reaching the surface, heat radiated by the sky and surface, water vapor, cloud water and cloud base height.

“The properties of low-altitude clouds appear to be different here, with much larger amounts of supercooled liquid water and smaller droplets than over Northern Hemisphere oceans,” Marchand said. is below its freezing point while remaining a liquid.

The field experiment hopes to learn why low-cloud properties are different in this region. It will also provide new measurements of the daily and seasonal changes in cloud cover, and help ground-truth measurements coming from satellites 鈥� something that has not been done much for the stormy, inhospitable Southern Ocean.

Marchand hopes that the project will become part of the larger Southern Ocean Cloud Rainfall and Aerosol Transport experiment, or , which if funded will put him and colleagues from the 91探花and elsewhere aboard ships and aircraft to get more firsthand measurements of Southern Ocean clouds.

MICRE is an international collaboration between the U.S. Department of Energy, the Australian Bureau of Meteorology and the Australian Antarctic Division, which operates a research station on Macquarie Island. After weather-related delays, a French ship was able to deliver the instruments to the island in late March.

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For more information, contact Marchand at 206-616-0620 or rojmarch@uw.edu. Note: He will be out of town April 11-15.

See also a from the Department of Energy.