NASA- ESPO TC4
Two Columns
TC4; Science Overview
The tropical tropopause transition layer (TTL) is one of the most mysterious regions of the atmosphere. Only a handful of research aircraft are able to reach the layer, which extends from about 12 km altitude to a few kilometers above the tropopause (the coldest point in the lower atmosphere), which is located at about 16-17 km altitude. Satellites have opened a new window into the TTL but they have difficulty observing it because there are often high clouds in the layer, which obscure the view, and because it has less mass than the underlying regions of the atmosphere. However, the TTL is of critical importance to the Earth's climate and atmospheric chemistry. The TTL is the gateway to the stratosphere. Deep convection sometimes penetrates the TTL to reach the stratosphere, while gentle upward motions within the TTL may also loft materials across the tropical tropopause. Hence the chemistry of the stratosphere may be affected in a significant way by processes that alter the transport across the TTL and by the chemicals in the TTL. Changes in water vapor in the stratosphere and upper troposphere can play an important role in modulating the climate since water is the most powerful greenhouse gas in the atmosphere. The TTL is the main dehydration region for air entering the stratosphere, and it is also an important reservoir for moisture lofted by tropical convection. Understanding how water behaves in the TTL is one key to better understanding the greenhouse effect, and global climate change. The TTL also contains cirrus clouds. One type of cirrus forms from anvils, the flattened tops of tropical cumulus clouds. Tropical cumulus pump vast quantities of air in just a few minutes from near the tropical surface to the TTL where they spill the air out into their anvils. The TTL also contains cirrus clouds that may be formed in situ. Many of these are so thin that they cannot be seen with the naked eye and so are called sub-visible cirrus. These clouds are easily seen by satellite however, and are now known to cover a large fraction of the tropics. Finally, the transport to and evolution of trace gases such as ozone in the TTL play an important role in determining what gases are carried into the stratosphere and upper troposphere globally. In order to learn more about the mysterious TTL NASA has designed the Tropical Composition, Clouds and Climate Coupling Experiment, TC4. Three NASA research aircraft will complement a suite of NASA Earth observing satellites during July and August of 2007 as part of TC4. There will also be ground based observing facilities and balloon launches. Participants will come from multiple NASA centers, NOAA, NCAR, numerous universities, and Costa Rica. more >>
ESPO News:
ICESCAPE NewsOIB Arctic Mar-May 2012
HS3 Aug-Sep 2012
OIB Antarctic, Oct-Nov 2011
HS3, Aug-Sep 2011
ATTREX Jan-Feb 2013
SEAC4RS Aug-Sep 2012
Seagrass Apr-May, Nov 2012 & Jan 2013
Aircraft: SIERRA
Location(s): Cedar Key, FL, Key West, FL and Republic of Trinidad and Tobago
Science Goals: High Resolution Assessment of Carbon Dynamics in Seagrass and Coral Reef Biomes; Science objectives are to image sea grass and coral for understanding carbon dynamics in addition to improving methodologies for calibrating orbital imagery in the littoral zone.
ESPO Role/Lead: ESPO is providing logistic support - Quincy Allison and Marshal Chaidez
Aircraft: NASA WFF P-3, LaRC HU-25 Falcon
Location(s): Thule and Kangerlussuaq Greenland, Fairbanks AK
Science Goals: Ongoing investigation of the thinning and movement of Antarctic Sea and Land Ice. Data collected during IceBridge will help scientists bridge the gap in polar observations between NASA's Ice, Cloud and Land Elevation Satellite (ICESat) -- in orbit since 2003 -- and ICESat-2, planned for late 2015. ICESat stopped collecting science data in 2009, making IceBridge critical for ensuring a continuous series of observations. IceBridge will use airborne instruments to map Arctic and Antarctic areas once a year.
ESPO Role/Lead: ESPO providing Deployment Management - Kent Shiffer (DM), Jhony Zavaleta (Deputy DM).
Others: Jhony Zavaleta returned once again to Thule Greenland at the end of May to complete wrap up the mission details with the Thule Air Base operations.
Accomplishments this past month: Operation IceBridge is now complete. The LaRC falcon has completed all of its expected flight lines and has returned to Langley. The WFF P-3 has also completed an unprecedented Cryospheric campaign and returned to the US on May 25th.. Flying over 328 total hours including 252 science hours at an estimated distance of 82,815 nautical miles over the arctic and island of Greenland. All P-3 and Falcon flight reports can be viewed on the ESPO OIB web site at: Web Site
Aircraft: NASA DC-8, NSF G-V
Location(s): Punta Arenas, Chile
Science Goals: Ongoing investigation of the thinning and movement of Antarctic Sea and Land Ice. Data collected during IceBridge will help scientists bridge the gap in polar observations between NASA's Ice, Cloud and Land Elevation Satellite (ICESat) -- in orbit since 2003 -- and ICESat-2, planned for late 2015. ICESat stopped collecting science data in 2009, making IceBridge critical for ensuring a continuous series of observations. IceBridge will use airborne instruments to map Arctic and Antarctic areas once a year.
ESPO Role/Lead: ESPO providing Deployment Management - Kent Shiffer (DM), Jhony Zavaleta (Deputy DM).
Other details: This is the first time the NSF G-V has joined the OIB team and will fly the LVIS instrument at high altitude. (Land, Vegetation, and Ice Sensor).
Web Site
Aircraft: 2 Global Hawks (AV-1 and AV-6)
Location(s): WFF (Wallops)
Science Goals: To investigate the processes that underlie hurricane formation and intensity change in the Atlantic Ocean basin.
ESPO Role/Lead: ESPO providing Project Management - Marilyn Vasques (PM), Bernie Luna (Deputy PM)
Other details: This will be the first deployment of the GH to a remote location and the first use of its 2nd ground set. It will also be the first time NASA will fly 2 GHs on the same mission. Both GHs will not fly a storm at the same time but shortly after one returns to base, the other can take off. The Payload Mobile Operations Facility (PMOF) is expected to transit to WFF July 6. More info at HS3Web site
Current plan
Integration begins: July 1
GH 872 (AV-6) transits to WFF: Aug 29
Science flights begin Sept 1
GH 871 (AV-1) transits to WFF Sept 7
Science flight complete Oct 5
Accomplishments this past month: Science team telecon conducted May 23rd. Preparations for integration and deployment continue. Science, operations, safety and E/PO telecons continue and operations, safety and budget documentation is in work. During a flight of the ongoing KQX/DARPA tests, the Global Hawk flew within 40 feet of each other. Although this is not a requirement for HS3, it is a major milestone for KQX. After a few weeks of analysis, they will fly again and attempt to connect the aircraft for air-to-air refueling. The two GHs were to be turned over to HS3 June 30. HS3 just got a request to explain the impact of giving KQX 2 more weeks. The impact will be severe and the justification will be presented by HS3 June 12.
Aircraft: Global Hawk AV-6
Location(s): DFRC
Science Goals: Further investigate the water vapor physics and the chemistry of the tropical tropopause
ESPO Role/Lead: ESPO providing Project Management - Dave Jordan (PM), Jhony Zavaleta (Deputy PM).
Other details: Web Site
Aircraft: NASA ER-2, DC-8, NSF G-V
Location(s): Utapao Thailand
Science Goals: This scientific experiment will address key science questions regarding the influence of Asian emissions on clouds, climate, and air quality as well as fundamental satellite observability of the system. SEAC4RS will facilitate progress in understanding and improving predictive capability for changes in the ozone layer, climate forcing, and air quality associated with changes in atmospheric composition.
ESPO Role/Lead: ESPO providing Project Management - Kent Shiffer (PM), Jhony Zavaleta (Deputy PM).
Other details: Other aircraft may join the SEAC4RS team including the Royal Thai Rainmaking operation. SEAC4RS Web Site
Accomplishments this past month: The DC3 NSF/NASA mission, (preliminary mission to SEAC4RS) is currently deployed with the NASA DC-8 and NSF G-V aircraft in Salina KS. ESPO team members Kent Shiffer and Sue Tolley are planning to visit Thailand again to finalize deployment site particulars on June 16th. They will be joined by an ER-2 pilot and will review the facilities and provide a safety briefing to the airport.
