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The development of small unmanned aerial systems (sUAS) with a variety of sensor packages, enables in situ and proximal remote sensing measurements of volcanic plumes. Using Costa Rican volcanoes as a Natural Laboratory, Dr diaz un collaboration with 4 NASA centers have started an initiative to develop low-cost, field-deployable airborne platforms to perform volcanic gas & ash plume research and in-situ volcanic monitoring in general, in conjunction with orbital assets and state-of-the-art models of plume transport and composition.

Several gas sensors including a miniature mass spectrometer, and an electrochemical SO₂ sensor, combined with temperature, pressure, relative humidity, and GPS sensors, have been deployed into the active plume of Turrialba Volcano. Several different airborne platforms such as manned research aircraft, unmanned aerial vehicles, tethered balloons, as well as man-portable in–situ ground truth systems are being used for this research. Remote sensing data is also collected from the ASTER and OMI spaceborne instruments and compared with in situ data. The deployments demonstrated a path to study and visualize gaseous volcanic emissions using mass spectrometer and gas sensor based instrumentation in harsh environment conditions to correlate in situ ground/airborne data with remote sensing satellite data for calibration and validation purposes The deployment of such technology improves on our current capabilities to detect, analyze, monitor, model, and predict hazards presented to aircraft by volcanogenic ash clouds from active and impending volcanic eruptions.

Host Simon Carn

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Over the past twelve years, the speaker and collaborators have developed a new method for simulating circulations in geophysical fluids. A body of water or an atmosphere is represented as a collection of conforming fluid parcels whose motions are predicted using Newtonian mechanics. The method employs a unique convective parameterization, referred to as Lagrangian Overturning (LO), in which overlapping fluid parcels exchange vertical positions in convectively unstable regions. This talk will introduce the Lagrangian method, present idealized tests that illustrate its advantages, and summarize lake, ocean and atmosphere applications completed to date, which include simulations of large lake upwelling, Atlantic meridional overturning, and tropical convective systems.

Host Raymond Shaw

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This talk will have two segments. The first one will cover the results of five years of observations using a suite of instruments over Pune (18° 32′ N, 73° 48′ E, 559 m amsl), India. The second will discuss the results of a camping carried out over an Oceanic region (Bay of Bengal: 80°–100°E, 5°–22°N), surrounded by densely populated and industrialized countries. In particular, I will discuss the optical and chemical properties and the size of atmospheric particulate (Aerosols). Aerosol, although very small in size(less than a micron), pose serious challenges to achieve accurate modelling projections of the future climate of our planet. The difficulty in accurately model the effects of aerosol on the Earth radiative balance is also due to the fact that their properties like size distribution, single scattering albedo, asymmetry factor etc., have shown to have large variability from region to region over globe. This talk will highlight some of these complexities and the importance that these observations have for climatic studies.

Host Claudio Mazzoleni

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Over the last 30 years, tremendous progress has been made in our understanding of the processes that govern the evolution of the Earth System and specifically the climate system. The influence of the human enterprise has been so large that we are entering in a new period of our geological history dominated by human impacts, now called the Anthropocene. The talk will review some of the major impacts of human activities on the Earth System. It will highlight key challenges that have been posed to the scientific community in the last century (predicting weather, projecting climate, improving air quality, etc.), and discuss successes and failures. The challenges for the future are very different; they will be directly related to the major issues facing our society under climate change: a transformation of the energy system, the need to ensure food security and water availability, the improvement of the health and education systems and the eradication of poverty. Government and international organizations have attempted to address a number of major environmental issues, but successes have been limited. Planetary stewardship requires new interdisciplinary approaches, two-way communication between scientists and stakeholders. The science will play a fundamental role in addressing these issues, but the traditional climate and environmental research much be complemented by a well designed approach to adaptation to planetary changes.

Guy Brasseur is with the Climate Service Center Helmholtz Center, Geesthacht, Germany and Advanced Study Program National Center for Atmospheric Research Boulder, CO.

READ MORE about the Honrath Memorial Lecture for Fall 2012.

Host Will Cantrell - Honrath Lecture

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An enhanced TIMESAT algorithm was developed for retrieving vegetation phenology metrics from 250m and 500m spatial resolution Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation indices (VI) over the North American continent. MODIS VI data were pre-processed using snow-cover and land surface temperature data, and temporally smoothed with the enhanced TIMESAT algorithm. An objective third derivative test was applied to define key phenology dates and retrieve a set of phenology metrics. This algorithm has been applied to two MODIS VIs: Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). The comparison between the retrieved phenology metrics and the ground reference indicates satisfied result. All data sets are available through a web-based data distribution system. The phenology metrics has been applied to produce the potential nectar flow date map over the Eastern United States. This set of maps shows the annual variation of 50% nectar flow date. They could be a direction of hunting honeys.

Host Shiliang Wu

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Langmuir cells are small (O(5-100m)), three-dimensional, circulations in the upper ocean. These cells often form into a jumbled array of cells called Langmuir Turbulence. Both Langmuir turbulence, and hence Langmuir cells, result from an interaction of surface waves and windstress. Submesoscale eddies are slightly larger (1-10 km) and result from instabilities caused by surface temperature fronts. While Langmuir turbulence dramatically mixes the ocean, submesoscale eddies act to reverse this mixing.

In this talk, possible impacts of each of these small-scale processes on the large scale ocean will be examined separately. To understand how submesoscale eddies and Langmuir turbulence interact, including how this combined interaction influences the larger ocean, unprecedented simulations have been conducted that resolve Langmuir turbulence and submesoscale eddies. These simulations have and will provide insight into upper ocean physics and guidance to ocean model development for years to come.

Host Raymond Shaw

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Liquid water is the most abundant condensed phase species in the atmosphere, 2-3 times aerosol dry mass and clouds cover roughly 60% of the Earth's surface at a given time. Muliphase and heterogeneous chemistry involving atmospheric waters is associated with critical air quality and climate issues, such as the deleterious ecosystem effects of acid deposition and stratospheric ozone depletion. Yet chemical mechanisms employed in atmospheric photochemical transport models largely neglect the impact of the aqueous medium, in particular for organic species. This hinders development of effective strategies for air quality management and climate mitigation because important processes and feedbacks are missing from model predictions. A solubility index is developed to describe the potential of organic gases to partition to liquid water in a common framework that takes into account spatial and temporal variability among organic gases and particle phase water. This framework contributes to the indication that anthropogenic pollution enhances formation of secondary organic aerosol (SOA) from biogenic VOC precursors, and provides mechanistic insight to an additional anthropogenic influence, namely the ability of sulfur pollution to increase the amount of particle phase liquid water in the atmosphere. The solubility index and partitioning potential may resolve a key discrepancy whereby biogenic SOA mass concentrations in the southeast U.S., where anthropogenic pollution and biogenic emissions routinely mix and particle phase liquid water concentrations are predicted to be high, are much greater than biogenic SOA mass concentrations in the Amazon.

Host Lynn Mazzoleni

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Distinct seismic and sonic signals accompany volcanic unrest. By analogy with light, these signals often exist on the lower frequency or red end of the spectrum. The identification and interpretation of low frequency signals poses a challenge for volcano monitoring, since earthquake processing systems are tuned to most reliably detect high frequency seismicity. In this talk, I present examples of low frequency seismicity observed during eruptions at Alaskan volcanoes and discuss the insights into magmatic systems derived from these signals. I further demonstrate long-range detection of low frequency sound waves, or infrasound, generated by volcanic explosions and its utility for real-time alarms. I end with an analysis of five unusual low frequency earthquakes recently observed at Little Sitkin Volcano, Alaska, that were precursory (4-6 days prior) to the beginning of a shallow earthquake swarm beneath the volcano.

Host Greg Waite

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Organic aerosol (OA) mass comprises a large fraction of atmospheric particulate matter. A large portion of OA is produced by physical and chemical processes in the atmosphere and is referred to as 'secondary organic aerosol' (SOA). Most current models describe SOA formation by condensation of low volatility and semivolatile compounds on preexisting organic particles (gasSOA).

While recent model studies have shown that SOA mass can sometimes be properly predicted, more detailed observation-model comparisons show that other distinct aerosol properties significantly diverge. These features include the modification of aerosol size distributions, product distribution, oxygen content (O/C ratio) of newly formed SOA mass. Many recent laboratory, field and model studies suggest that chemical processes in the aqueous phase of cloud (fog) droplets and deliquesced aerosol particles might also contribute to SOA (aqSOA) and could explain (partially) these discrepancies. In my talk, I will present specific aqueous phase mechanisms and contrast them to more traditional SOA formation pathways. In particular, I will discuss reaction pathways that do not occur in the gas phase and yield unique products such as oligomers and carboxylic acids.

I will show several examples of process model studies that predict aqSOA formation in clouds and aqueous particles at various locations. In addition, aerosol characteristics will be discussed that could be used to distinguish aqSOA and gasSOA in ambient data based on a unique 'aqSOA signature'. While such process models allow the implementation of explicit, complex chemical mechanisms, in larger scale models simplified expressions have to be used. I will share some ideas on the development of such parameterized expressions and the key parameters they need to include.

Barbara Ervens is with the Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, CO, Chemical Sciences Division, Earth System Research Laboratory, NOAA, Boulder, CO.

Host Lynn Mazzoleni

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As geoscientists and geo-educators, we strive to understand the Earth system and offer that understanding as a resource to help society manage its relation with the planet. This is getting harder because of eroding support for basic research, politicization of scientific knowledge (e.g. climate change), and changing national demographics that exacerbate our historic difficulty reaching diverse communities.

One way to approach these challenges is by engaging diverse communities as partners in science—working with communities to develop an integrated program of scientific research, education, and action that addresses their priorities and advances general understanding. This approach invites community participation at all stages of the research process including defining the question and methods, collecting and analyzing data, and sharing and applying the results. While this approach is relatively new to physical sciences, it has a longer and successful history in natural resource management, social science, and public health.

This talk will explore this approach through specific examples: collaborations with tribal communities around climate change adaptation, work in the Louisiana Delta concerning land loss, and explorations of the link between weather and disease in Africa. I will articulate some of the challenges of working this intensively with communities, and suggest a general framework for guiding this kind of community-based science. I'd also like to explore strategies for scaling up this approach, especially with respect to how we train and reward future scientists.

Host John Gierke

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The primary goal of this investigation is the development of new and improvement of the existing methods and models of terrain trafficability prediction based on a combination of several remotely sensed modalities. These include Hyperspectral Imaging (HSI), Synthetic Aperture Radar (SAR), Thermal Infra-Red (TIR), and LiDAR (Light Detection and Ranging) techniques. Two field campaigns have been undertaken so far, including a preliminary short exercise at the VA Coast Reserve and an extensive field effort in North Eastern Australia as part of joint US-AUS work. Remote (aircraft-based) data collection program was designed together with a ground-based campaign, which included proximity HSI studies, utilizing a new NRL Goniometer instrument, and a comprehensive geotechnical suite of field measurements and sample collection for subsequent laboratory analysis. This talk will focus on description and analysis of these experimental efforts, and the preliminary results obtained. Additionally, several important findings from laboratory studies of reflectance on field-collected and lab-reconstituted samples will be discussed.

Host Greg Waite

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The Northern Gulf of Mexico (NGOMEX) experiences extensive seasonal hypoxia that is predicted to cause declines in the production of commercially and recreationally valuable fish and shellfish. In order to understand the direct and indirect effects of hypoxia on food web dynamics and ecological and economically important species, we developed an Atlantis ecosystem model and compared the model results to the available satellite remote sensing data. The Atlantis framework is a three-dimensional biogeochemical and biophysical modeling system that uses hydrodynamic model output as a forcing function and simulates biochemical cycles and food web interactions. Nutrient and field observations from 2003-2008, and from Southeast Area Monitoring and Assessment Program (SeaMap) were used to initialize the Atlantis ecosystem-based model and the in situ data were also compared to salinity, temperature and chlorophyll values from the available satellite imagery. This included coincident satellite data from the Aquarius satellite (salinity) the Moderate-resolution Imaging Spectroradiometer (MODIS) and the MEdium Resolution Imaging Spectrometer (MERIS). The output of the NGOMEX Atlantis model helped define the extent and seasonal timing of hypoxia on predator-prey interactions and directional change in the food web components. Our overall goal is to use these results to forecast the effects of hypoxia on NGOMEX living resources by uniquely combining both satellite and ecosystem based model results.

Host Louisa Kramer

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Biomass burning is a major source of atmospheric trace gases and particles that impact air quality and climate at urban, regional, and global scales. Within minutes after emission, rapid, complex photochemistry within a smoke plume can cause large changes in smoke composition. In some plumes, this can lead to significant increases in the concentrations of ozone and aerosols after less than an hour of aging, while in other, generally boreal, plumes only small changes are observed. Being able to understand and simulate this rapid chemical evolution under a wide variety of conditions is thus a critical part of forecasting the impact of these fires on urban and regional air quality. In this talk, I will discuss how aircraft and satellite observations, when combined with state-of-the-art chemical transport models such as the Aerosol Simulation Program (ASP), can be used to evaluate the ozone and aerosol formation within smoke plumes. Focusing on biomass burning plumes recently sampled over California and the Yucatan, we will examine several potential explanations for the high levels of OH and ozone observed within these smoke plumes, such as (1) the photolysis of HONO emitted directly by the fires, (2) the secondary formation of HONO from NOx via heterogeneous chemistry within the smoke plume, and (3) the recycling of OH during the oxidation of some organic gases within the smoke plumes, as has been observed for isoprene.

Host Louisa Kramer