Department of Energy
An anvil cloud looms over the Southern Great Plains where DOE and NASA climate scientists are headed to study the physics of convective clouds in a bid to improve models of the global climate.
As spring storms rumble across the Great Plains in the coming weeks, government scientists will have their heads in the clouds hoping to gain a better understanding of the dynamics at play so they can improve models of the global climate.
"One of the real areas of hot debate in our field these days is what happens to the strength of storms as the climate warms," Michael Jensen, a meteorologist with the Department of Energy's Brookhaven National Laboratory, told me today.
Jensen is leading a six week field campaign beginning Friday in Oklahoma to study why these storms form where they do, how they grow over time and what causes them dissipate. The data, to be collected with state-of-the-art radars, wind profilers, NASA aircraft and weather balloons, will allow scientists to improve models they use to predict how these storms will change as the climate warms.
Current models are unable to accurately to reproduce these convective clouds. For example, the models tend to start forming them earlier in the day and produce really big storm clouds at the expense of the more common intermediate storms.
Convective clouds, or systems, are the towering masses formed by rising heat that can produce thunderstorms and other severe weather, including tornadoes such as those that swept across the southeast last weekend, killing several dozen people.
These so-called convective processes play a critical role in Earth's energy balance by redistributing heat and moisture in the atmosphere and triggering precipitation.
Although these are the processes that build up the storms that lead to severe weather, such as tornadoes, Jensen's team is most interested in "the much more typical afternoon spring and summer type thunderstorms that you experience in the plains," he said.
The experiment will employ a range of atmospheric measuring equipment on the DOE's Atmospheric Radiation Measurement Southern Great Plains site in Oklahoma, such as a suite of radars to study the properties and evolution of clouds in three dimensions. Other instruments at the facility will measure winds and precipitation.
NASA participants will fly aircraft within and above the cloud systems to collect complementary data on the amount of moisture and structure of the clouds. "Now we need the weather to cooperate a little bit. We need it to rain some while we are out there," Jensen noted.
The suite of instruments all running at the same time should give the scientists a holistic view of convective processes including:
- the atmospheric conditions in which a convective cloud forms,
- how air motions within the cloud impact the subsequent growth and formation of precipitation,
- what types and sizes of cloud and precipitation occur within the different stages of the cloud life cycle
- and how the cloud system impacts the background atmosphere
The end goal is to provide the most complete characterization of convective cloud systems and their environment that has ever been obtained, providing information that has never before been available for representing these processes in global climate models.
"We know that one of the biggest uncertainties in the climate models is the representation of clouds and the feedbacks they have within the climate system," Jensen told me. "This is just one of the cloud types that we need to continue to understand better to improve the climate models even further."
More on climate and clouds:
- How do clouds affect Earth's climate?
- Warming experts stick their heads in the clouds
- Are mystery clouds of Venus a warning sign for Earth's climate?
- Photoblog: Tracks in the sky
John Roach is a contributing writer for msnbc.com. Connect with the Cosmic Log community by hitting the "like" button on the Cosmic Log Facebook page or following msnbc.com's science editor, Alan Boyle, on Twitter (@b0yle).