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Develop and maintain high-quality instruments and field campaign serviceObservations are needed to test theories, substantiate model development, and, in general, provide data to help advance science and contribute to discoveries. Within ESSL the HAO maintains and operates the Mauna Loa Solar Observatory which captures solar data through a bevy of instruments and provides this data to the community. ESSL also provides the community with a variety of instrumentation for sampling and analyzing the chemical constituents in the atmosphere. ESSL participates in, and in some cases, leads field experiments, such as the Megacities Impact on Regional and Global Environment (MIRAGE) and the future Deep Convective Clouds and chemistry Experiment (DC3) experiments. Below are projects that develop and maintain high-quality instruments and field campaign services. Mauna Loa solar observatory and data [Highlight]
- HAO Mauna Loa solar observatory and data
Observations of the lower solar atmosphere, such as those acquired at MLSO, are needed to understand the heating of the solar corona, the continual outflow of material that comprises the solar wind, and the causes of solar activity and space weather. Conditions in the solar atmosphere vary dramatically from those that exist in the solar photosphere. The million-degree coronal plasma is highly electrically conducting and `frozen' onto magnetic field lines. Unlike the solar photosphere, the energy of the low corona is dominated by the magnetic field, which organizes the corona into magnetically `closed' and `open' regions that are the sources of the solar wind. The solar wind ultimately determines the conditions in interplanetary space at Earth and throughout the solar system. The Earth's magnetic field and associated current systems are continually reacting to changing conditions in the solar wind, driven by processes occurring at the Sun. During periods of high solar activity, highly energized particles, accelerated by CMEs and flares can stream toward Earth and pose hazards to astronauts and satellites. CMEs can generate severe geomagnetic storms, which can damage power grids, satellites and affect GPS and other important navigation and communication systems. Understanding the causes of such magnetic activity in the Sun's corona, the propogation of the disturbances it produces through interplanetary space, and the occurrence and impacts of associated space weather events on the Earth's magnetosphere and upper atmosphere are among the highest scientific priorities of HAO, ESSL, and NCAR. Recent observations using the instruments comprising the Advance Coronal Observing System (ACOS) at MLSO have yielded valuable insights concerning the coronal conditions that prevail prior to the initiation of a CME, the phenomena related to the occurrence of a CME, and the acceleration of CMEs in the low corona following eruption. For example, observations with the Mark 4 Coronameter have revealed that coronal cavities are ubiquitous, stable features in the low corona that erupt as part of a CME. Such cavities are consistent with the presence of magnetic flux ropes in pre-CME magnetic configurations, and observations of them them therefore provide information about the state of corona prior to the occurrence of a CME. MLSO neutral helium observations show that transient coronal holes are also associated with CMEs. These features form during the impulsive phase of solar flares and are co-spatial and co-temporal with transient coronal holes observed in extreme ultraviolet light, suggesting that they are a manifestation of the decrease in coronal density that results from the occurrence of a CME. Similarly, MLSO neutral helium observations of chromospheric waves, also connected with CMEs and flares, demonstrate that they are co-spatial with waves observed in the extreme ultraviolet. Multiple waves are observed during each CME event, an indication that a slow-mode wave compression in the chromosphere is followed by a slow-mode wave rarefaction, and that multiple drivers (e.g. CMEs, and flares) may be present for a given event. MLSO observations have furthermore shown that nearly all (80 to 90%) CMEs are linked with an active or erupting prominence and that CME acceleration peaks in the low corona (below 3 solar radii). Moreover, the CMEs with the largest accelerations (and highest speeds) are found to be strongly associated with solar energetic particle events, while the prominence accelerations appear to be correlated with the speed of the overlying CME. In addition to continued daily monitoring of the physical state of the low corona, future activities will include support of efforts to develop the COronal Solar Mangetism Observatory (COSMO), a community facility for studying the magnetic structure and dynamics of the outer solar atmosphere. This facility will house the next generation of coronal instrumentation, and will make possible coronal and prominence magnetic field measurements that will further understanding of the coronal responses to changes in photospheric magnetic flux on both short and long time scales.
Community "chemistry" instruments
ACD scientists, in collaboration with EOL staff, developed, maintain, and operate several instruments that are available to the community for use on NSF aircraft operated by NCAR. These instruments measure CO, CO2, and water vapor. The instruments are requested for a particular campaign as a part of the procedure for requesting the aircraft facility. Two instruments were purchased, certified, and integrated onto the NSF Gulfstream-V for two G-V research projects during this year. Instruments to measure CO and H 2 O supported the CHAPS, START, DOCIMS and New Particle Formation subprojects of the Progressive Science mission. The START and New Particle Formation flights explored dynamics and transformations in the UT/LS region. In particular, START characterized gas phase and thermodynamic tracers in the area of mid-latitude stratospheric intrusions. The CHAPS flight hours were directed at G-V instrumentation testing and validation, and the objective of the DOCIMS flights were to characterize lower tropospheric dynamics of marine stratocumulus clouds. For the G-V Terrain-induced Rotors Experiment (T-REX), the CO and H 2 O measurements also contributed valuable in situ tracer data. The campaign was designed to study factors influencing Rotor formation and orographic wave formation and propagation. The study area targeted a region of the Sierra Nevadas near Bishop, CA, although the G-V operated out of Jefferson County Airport. Additionally, the payload also included a test version of the HAIS O 3 instrument. The mission scientists have acknowledged the hope that these additional measurements may enhance their ability to probe the impact of orographic waves on local dynamical processes. In support of the MILAGRO/MIRAGE project, which examined regional and global impacts of pollution from Mexico City, observations of CO, water vapor, and CO 2 were made from the C-130 during the March, 2006, field intensive. The C-130 was based in Veracruz, Mexico. The same observations were applied to explore the impact of Asian transport of pollutants on the northwestern North America during INTEX-B (April-May, 2006). The C-130 was based in Seattle, WA. For both experiments, the combination of CO and CO 2 observations can be used as an indicator of air mass history. FY2007 work will include data analysis from T-REX, MIRAGE, and INTEX-B as well as ongoing calibration efforts for each instrument. This work is funded by NSF/NCAR wit supplemental funding from NASA for INTEX-B. Planning of DC3 field program
The DC3 Field Experiment will characterize the effect of midlatitude, continental convection on the transport and transformation of ozone and its precursors. Along with measurements of hydrogen oxide radicals, their precursors, and nitrogen oxides in both the inflow and outflow regions of deep convection, measurements of cloud microphysical properties, storm kinematics, and lightning discharges will be conducted. These measurements are planned for the central United States during summer 2009 where remote continental regions can be contrasted to anthropogenically-influenced regions. A planning workshop was held in April, 2006 at NCAR to discuss and refine the science program and experimental design of DC3, and to form DC3 working groups to help plan the field experiment. Approximately 50 people attended the two day workshop. The field experiment is proposed to occur in summer 2009 over the central United States (Colorado-Kansas-Oklahoma) with an extension to northern Alabama. The primary goals of DC3 are:
The participants were in favor of these goals and had comments on specific issues. These comments included a) identifying types of convection that would be best in addressing the scientific goals, b) quantifying the (20- 30%) effects of certain processes via models when the model-measurement agreement is of the same order (20-30%), c) examining the scavenging (wet deposition) of soluble species from different types of convection and via tracer ratio analysis, and d) finding the convective outflow plume via forecasts, and the practicalities of sampling downwind convective outflow with the same aircraft that is sampling the active convection. These issues were discussed during the workshop breakout sessions. Ancillary goals of DC3 are to investigate halogen chemistry, mass fluxes of trace gases, lightning discharge and electrification processes, the water budget, and aerosol-cloud particle connections. Specific issues commented on during the workshop were a) the effect of lightning on halogens – this may also be of interest to other radical species such as OH, b) mass flux studies are of particular interest but there is a challenge of sampling storms that continually evolve with time, c) the transport of water vapor (and other trace gases) into the stratosphere via deep convection, d) the need for satellite data analysis for guiding the field experiment, and e) the importance of aerosol nucleation in cloud outflow regions. It is proposed to conduct DC3 at multiple locations in regions where sufficient groundbased facilities are already in place. The consensus from the workshop was to base the aircraft near Oklahoma City to sample deep convection in northeast Colorado, central Oklahoma, and northern Alabama. By having a multiple location sampling strategy, the likelihood of convection occurring in one of the three locations is high while the costs of the ongoing measurements at the ground-based facilities are minimized. Sampling convection in these three regions gives us the ability to contrast the influences of the different cloud physics and dynamics environments on the chemistry and composition of the convective outflow. The dry environment in northeast Colorado tends to produce high cloud bases and convection dominated by ice microphysics, while convection in Oklahoma and Alabama becomes progressively moister with lower cloud bases and more liquid phase cloud particles. Sampling multiple locations also allows us to contrast different chemical environments, which progressively increase in surface emissions of nitrogen oxides and biogenic hydrocarbons from west to east. Additional information on the meeting may be found at http://utls.tiimes.ucar.edu/Science/dc3.shtml FY2007 work will involve continued planning of DC3 with possible town meetings to be held at the annual Fall AGU and AMS meetings. This planning work is funded by NSF/NCAR. |
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A major research goal of ESSL is to understand the Sun's continuous and dynamic release of plasma and energy and to ultimately predict its impacts on the interplanetary environment. To support this goal, HAO, a division of ESSL, operates the Mauna Loa Solar Observatory (MLSO) on the island of Hawaii. MLSO instruments routinely record unique images of the solar chromosphere (in the neutral hydrogen alpha and neutral helium 1083 nanometer lines) and low corona every 3 minutes for approximately 9 hours/day (weather permitting). These data are essential for detecting the formation and occurrrence of solar activity such as Coronal Mass Ejections (CMEs), prominence eruptions, flares, and related phenomena. MLSO has been in operation since 1965, providing the longest extant record of changes in the density structure of the solar corona over multiple, 11-year solar cycles. MLSO data are available via the internet at: 
