Washington, June 13 : Scientists are deploying an advanced research aircraft to study a remote atmospheric region that influences climate change by affecting the amount of solar heat that reaches Earth's surface.
Findings from the project, based at the National Center for Atmospheric Research (NCAR) in the US, will be used by researchers worldwide to improve computer models of global climate in preparation for the next report by the Intergovernmental Panel on Climate Change (IPCC).
The project, running from April to June, is known as START 08 (Stratosphere-Troposphere Analyses of Regional Transport).
It focuses on a remote boundary zone of the atmosphere called the tropopause, which sits at the bottom of the stratosphere.
Scientists are increasingly interested in the tropopause, because of both its importance in the global climate system and because the buildup of greenhouse gases has altered this atmospheric region in ways that are not yet fully understood.
"This region of the atmosphere is a weak link in climate research," explained NCAR scientist Laura Pan, a principal investigator on the project.
"In order to understand climate change, we need to have accurate computer models of the planet. In order to have accurate models, we need to understand what's going on in the tropopause," she added.
The research team is deploying the NSF/NCAR Gulfstream-V, a cutting-edge aircraft with high-altitude capabilities that will fly about a dozen missions above much of North America, ranging up to about 47,000 feet.
The flight paths will take the aircraft through the top of the troposphere, which is the lowest layer of the atmosphere, and into the stratosphere.
Focusing on the tropopause, the boundary between these two layers, scientists will take samples of air to determine the movements and concentrations of a number of gases.
One of their goals is to learn more about water vapor and ozone, which act as potent greenhouse gases by trapping solar radiation in the atmosphere, thereby warming the planet.
As Earth's tropical regions have grown, the highest part of the tropopause has extended farther north and south.
These changes are setting off a chain reaction that affects both weather patterns and long-term global climate.
The research team wants to determine how weather patterns stir up chemicals in the tropopause and, in turn, how the tropopause's changing chemical composition influences global climate, including the location of the jet stream.
According to Elliot Atlas, a principal investigator on the project and professor of marine and atmospheric chemistry at the University of Miami, "We want to collect data that will help map out the chemical composition of this dynamic boundary region."