Support Observing Needs of Research Programs at a level that Serves NSF, University and NCAR Program Needs
In FY 2011 EOL organized, conducted or otherwise participated in eight field programs that spanned a variety of scientific inquiry: the fourth and fifth campaigns of HIAPER Pole-to-Pole (HIPPO) (June-July 2011, August-September 2011); Western Airborne Mercury Observations (WAMO) (October 2010); Concordiasi (August - November 2010); the Persistent Cold Air Study (PCAPS) (December 2010 - February 2011); the Winter Storms and Pacific Atmospheric Rivers (WISPAR 2011) (January - March 2011); the Deep Convective Clouds and Chemistry (DC3) – TEST (May 2011); and the Ice in Clouds Experiment - Tropical (ICE-T) (July 2011).
HIPPO, a massive three-year, five-mission global research campaign, ended in September 2011 and is already revealing exciting new details about the latitudinal and vertical distribution of greenhouse gases and other atmospheric constituents. EOL and the HIPPO research team completed five multi-leg missions from Arctic to Antarctic latitudes, and from near the surface to the lower stratosphere. These missions, carried out in 2009, 2010 and 2011, sampled over one hundred chemical, aerosol, and state variables with sensors aboard the NSF/NCAR GV aircraft. These measurements are of significance to the climate community because they help track the movement of greenhouse and related gases through the atmosphere and improve our ability to resolve emissions associated with human activities, indirect effects of climate change, and natural variations. A strategy similar to that used by Stephens et al. (2007) can now be used with a much more extensive dataset that spans the vertical extent of the troposphere.
During HIPPO, scientists measured cross sections of atmospheric concentrations, approximately pole-to-pole, from the surface to the tropopause at different times of the year to see how seasonal changes affect atmospheric chemistry. For all five missions, EOL deployed the NSF/NCAR GV with a comprehensive suite of instrumentation to measure carbon cycle tracers and related species throughout the campaign. During the research flights the GV repeatedly climbed as high as 8.5 miles and dipped down to several hundred feet above sea level as it sampled more than 100 atmospheric constituents, including greenhouse gases, aerosols and a suite of natural and industrial chemicals.
In FY 2011 EOL conducted HIPPO Phase IV and the final Phase V, in June-July and August-September 2011, respectively. All Phases of HIPPO were successful in terms of data acquisition, and have been heavily covered by the news media, sparking an impressive amount of public interest in the project. The education and outreach components of HIPPO have been especially successful (see Imperative V).
In October 2010 the NSF/NCAR C-130 and EOL scientists participated in ICARE, an international conference hosted by Meteo France and the European Facility for Airborne Research (EUFAR) in Toulouse, France. During ICARE, scientists and aircraft operators involved in airborne geosciences research were invited to share experiences at specialized workshops and to contribute to a look ahead at user requirements and operator development strategies. The conference was a chance for researchers to compare notes on aircraft developments and operational issues (e.g. aircraft certification and airspace issues), as well as open doors for opportunities for international scientific collaboration.
More than 10 aircraft from agencies all over the world participated in the conference, affording a unique opportunity to compare and inter-calibrate airborne instruments through a series of inter-comparison flights. Data from those flights were made available in real time to researchers and students at the conference. It is envisioned that the inter-comparisons will improve the data quality for future airborne research, and it will likely result in publications describing the results. The conference was an opportunity for EOL to showcase the NSF/NCAR C-130 along with other international airborne research capabilities, to connect with scientists, operators of aircraft, and instrument developers on an international scale, and to facilitate future research collaborations with our international partners studying the Earth System.
WAMO was conducted on the ferry to ICARE.
Bioaccumulation of mercury is a problem with global and national significance; however there are large gaps in our understanding of the atmospheric mercury cycle. The information obtained in this project will significantly expand our knowledge of the chemical processing of Hg in the atmosphere and increase our understanding of the sources and sinks of mercury in the U.S. The project was a collaborative effort between the Universities of Washington and Nevada on atmospheric mercury, and built capabilities that will be critical for a larger project, proposed for 2013, to assess mercury sources, sinks and processing across North America.
The Concordiasi project was a joint US/French initiative that used a constellation of stratospheric superpressure balloons deployed from McMurdo Station, Antarctica to study the atmosphere over that continent and answer critical questions on chemistry and microphysics. EOL’s participation in Concordiasi was funded by NSF’s Office of Polar Programs and provided dropsonde observations using the EOL Driftsonde system. The main goal for the data gleaned from Concordiasi was to provide validation data for polar-orbiting satellite instruments over Antarctica whose measurements will be used to improve our understanding of the link between the Polar Regions and climate change. EOL staff deployed to McMurdo in late 2010 to prepare gondolas and assist scientists from Centre National d’Etudes Spatiales (CNES, France's equivalent to NASA) in launching balloons during the program.
Thirteen Driftsonde flights were successfully completed, with typical durations exceeding 50 days, up to five Driftsondes circling in the polar vortex at once, and over 650 dropsonde profiles collected. This exceptional operational success is expected to result in a reanalysis dataset that will be used to better assess precipitation and the mass budget of the Antarctic ice sheet, test and improve assimilation of infrared and microwave satellite observations over high latitudes, and help improve understanding of the relationship among ozone depletion, polar stratospheric clouds, and stratospheric dynamics. Lagrangian ozone and particulate measurements gathered at the balloons’ flight level, dynamics seen with dropsondes, and model output are being used together to constrain uncertainties in the rates of catalytic reactions involved in ozone depletion and to perform assimilation experiments of stratospheric ozone. The dense coverage of soundings (see figure, left) is the first time in history there has been this many soundings in such a short period of time in such a wide spatial density over Antarctica, and the data will keep scientists busy for years to come.
The goal of PCAPS was to study the persistent temperature inversions that occur each winter in the Salt Lake valley. Both the initiation and breakup of these persistent inversions, which occur frequently in the western US and throughout the world, are difficult to forecast. Air pollution can reach unacceptably high levels in persistent inversions in urban basins, and the breakup can carry pollution vertically to produce regional-scale air pollution and climate impacts. Because of poor mixing, fog and stratus can build up in the inversion, leading to hazardous episodes of persistent freezing rain, drizzle or fog and interfering with ground transportation and aviation.
PCAPS was a collaboration between the University of Utah, Michigan State University and NCAR/EOL and ran from December 1, 2010 to February 7, 2011. EOL deployed the ISS (Integrated Sounding System) and the Integrated Surface Flux System (ISFS) to the field for PCAPS.
EOL often leverages resources by incorporating technical developments into overall field project planning, and PCAPS was a perfect example of this. A prototype 449 MHz 3-antenna wind profiler was tested in Salt Lake City during the field campaign and its sensitivity and altitude coverage exceeded that of our co-located 915 MHz profiler. Further discussion of this prototype 449 MHz profiler system can be found in Frontier III.
Another example of the interdependent nature of EOL's deployment and development efforts is EOL's support of the WISPAR project. From January to March 2011 the EOL dropsonde team deployed to Edwards Air Force Base, CA in support of NOAA’s WISPAR field campaign. The focus of the research was to improve understanding of how Atmospheric Rivers (ARs) form and behave, and to evaluate the operational use of unmanned airborne systems (UAS), in this case NASA's Global Hawk, for studying these phenomena.
EOL used this opportunity to test our autonomous dropsonde launcher for the Global Hawk, which has been in development in a partnership with NOAA since 2009. There were three test flights in January 2010 to verify operations and identify technical issues with the system and for NASA to certify safe operations of the launcher. During the first two test flights, an F-18 jet flew alongside the Global Hawk to film the sonde ejections to verify safe separation from the UAS. The system also made history during the final test flight as it launched its 70th dropsonde from the Global Hawk over the Pacific ocean, the largest number of dropsondes ever deployed during a single flight.
Over the Pacific Ocean ARs transport large amounts of water vapor – about seven times the average daily flow of water from the Mississippi River into the Gulf of Mexico. The ability to monitor offshore ARs is expected to give researchers the ability to predict all manner of precipitation along the west coast, from storms that could produce beneficial increases in snowpack, to rainfall that could cause damaging floods. The long endurance of the Global Hawk coupled with the capability of deploying many sondes will enable unprecedented research into atmospheric river events and the forecasting of winter storms.
In May 2011 EOL conducted flights with the NSF/NCAR GV to test instruments required for The Deep Convective Clouds and Chemistry (DC3) field campaign, which will occur in summer 2012. Most instrumentation being flown on the GV for this project is new and nearly 20 cabin or wing-mounted instruments were tested during the 20 hours of flight time. The test flights also marked the passage and subsequent certification of the final three of the HAIS instrument suite: the Chemical Ionization Mass Spectrometer (CIMS), the Trace Organic Gas Analyzer (TOGA), and the Time of Flight Aerosol Mass Spectrometer (ToF-AMS).
The focus of the DC3 campaign will be to study the impact of continental, midlatitude deep convection on the upper troposphere and lower stratosphere (UTLS) composition and chemistry above the continental U.S. during the lifetime of the storm itself and during the period 12-48 hours after active convection.
The UTLS is an important region for Earth’s climate because water vapor, ozone, cirrus clouds and aerosols in this region strongly contribute to radiative forcing of the climate system. The UT and LS have very different chemical compositions resulting in strong gradients across the tropopause. The UTLS is also a highly dynamic region influenced by a broad range of scales, from deep convection and gravity waves, to tropospheric weather systems and the stratospheric large-scale circulation.
For DC3, the NSF/NCAR GV aircraft will be the primary platform to study the high altitude outflow of the storms, and will be instrumented to measure a variety of gas-phase species, radiation, and cloud particle characteristics. The GV will also document the downwind chemical evolution of the convective plume. The NASA DC8 aircraft will complement the GV via in situ observations to characterize the convective storm inflow and provide remote sensing to aid in flight planning and column characterization.
In addition, ground-based radar networks will be used to depict the physical and kinematic characteristics of storms and provide guidance to the aircraft operations. Also, measurements from ground-based VHF lightning mapping arrays will help constrain the impact of lightning on outflow composition.
EOL's NSF/NCAR C-130 supported ICE-T, led by NCAR's Andy Heymsfield, in July 2011 to provide in-situ instrumentation measuring the chemical, physical, and cloud activating properties of aerosols. The objective of the Ice in Clouds - Tropical (ICE-T) experiment is to show that under given conditions, direct ice nucleation measurements, or other specific measurable characteristics of the aerosol, can be used to predict the number of ice particles forming by nucleation mechanisms in selected clouds. The PIs also seek improved quantitative understanding of the roles of thermodynamic pathway, location within the cloud, and temporal dependency.
The ICE-T study, based in the US Virgin Islands, drew on lessons learned in ICE-L (2007), but extended the investigations to towering warm cumulus clouds, where both primary and secondary ice formation processes occur.
In addition to learning how ice particles form and affect clouds, ICE-T researchers are also hoping to improve measurement techniques for future airborne research campaigns. For example, graduate students compared three types of inlets to find out which design is able to most effectively capture the air inside of a cloud.