Staff Notes Daily Calendar Events

Thursday, May 7, 2015 - 3:30pm

Janice Coen
Mesoscale and Microscale Meteorology Laboratory
National Center for Atmospheric Research

Large wildfires can cover hundreds of thousands of acres and continue for months, varying in intensity as they encounter different environmental conditions, which may vary dramatically in time and space during a single fire. They can produce extreme behaviors such as fire whirls, blow-ups, bursts of flame along the surface, and winds ten times stronger than ambient conditions, all of which result from the interactions between a fire and its atmospheric environment and are beyond the capabilities of current operational tools.

Coupled weather-wildland fire models tie numerical weather prediction models to wildland fire behavior modules to simulate the impact of a fire on the atmosphere and the subsequent feedback of these fire-induced winds on fire behavior, i.e. how a fire “creates its own weather”. The methodology uses one such coupled model, the Coupled Atmosphere-Wildland Fire Environment (CAWFETM) Model, which contains two-way coupling between two components: (1) a numerical weather prediction model formulated for and with numerical methods optimized for simulating airflow at 100s of m in complex terrain, and (2) a wildland fire component that is based upon semi-empirical relationships for surface fire rate of spread, post-frontal heat release, and a canopy fire model. The fire behavior is coupled to the atmospheric model such that low level winds drive the spread of the surface fire, which in turn release sensible heat, latent heat, and smoke fluxes into the lower atmosphere, in turn feeding back to affect the winds directing the fire. CAWFE been used to explain basic examples of fire behavior and, in retrospective simulations, to reproduce large wildland fire events. Over a wide range of conditions, model results show rough agreement in area, shape, and direction of spread at periods for which fire location data is available; additional events unique to each fire such as locations of sudden acceleration, flank runs up canyons, and bifurcations of a fire into two heads; and locations favorable to formation of phenomena such as fire whirls and horizontal roll vortices.

The duration of such events poses a prediction challenge, as meteorological models lose skill over time after initialization, firefighting may impact the fire, and processes such as spotting, in which burning embers are lofted ahead of the fire, are not readily represented with deterministic models. Moreover, validation data for such models is limited and fire mapping and monitoring has been done piecemeal with infrared imaging sensors producing 6-hourly maps of active fires with nominal 1 km pixels, complemented by sub-hourly observations from geostationary satellites at coarser resolution and other valuable but non-routine tools such as airborne infrared mapping. Thus, CAWFE has been integrated with spatially refined (375 m) satellite active fire data from the Visible Infrared Imaging Radiometer Suite (VIIRS), which is used for initialization of a wildfire already in progress in the model and evaluation of its simulated progression at the time of the next pass.

Case studies of landscape-scale wildland fires will be presented to illustrate our current capability to model the unfolding of large fire events -- foremost for research and understanding, but also to assess their suitability as a predictive tool. Results show that using a cycling forecasting approach, in which a sequence of CAWFE simulations initialize the fire 'in progress' with VIIRS data and updated atmospheric analyses can overcome several forecasting issues and allow good representation of fire growth from first detection until extinction.

This seminar will be webcast live at:
http://www.fin.ucar.edu/it/mms/fl-live.htm

Recorded seminar link can be viewed here:
https://www.mmm.ucar.edu/events/seminars

Thursday, 7 May 2015, 3:30 PM
Refreshments 3:15 PM
NCAR-Foothills Laboratory
3450 Mitchell Lane
Bldg 2 Main Auditorium, Room 1022

Presenter(s):
Janice Coen
Type of event:
Seminar/Symposium
Building:
FL2
Room:
1022
Will this event be webcast by NCAR/UCAR?

Posted by Michelle Menard (menard@ucar.edu) at x8189
Lab/division hosting the event:
NCAR, MMM
Affiliation or organization:
Tuesday, May 19, 2015 - 11:00am

Energy exchange across the tropical air-sea interface plays a fundamental role in moist convection initiation, organization, and propagation.  Our understanding of these processes and their representation in global climate models is hampered by the complexities of moist convection, insufficient model grid resolution, and the small but growing amount of observational data.  Results from two air-sea interaction modeling projects are presented.  In the first, an atmosphere-only version of SPCAM highlights the response of the mean atmospheric state and MJO to prescribed SST perturbations associated with the Indian Ocean Dipole (IOD).  Unexpectedly, the MJO is largely insensitive to IOD SST anomalies within the Indian Ocean region, but it weakens significantly when the model is forced with IOD SST anomalies that occur contemporaneously in the Pacific basin.  Insights into this behavior and its implications will be discussed.  The second project leverages a modified configuration of 0.25° CESM coupled to an oceanic mixed-layer model (a 1D version of POP; “CESM-1dPOP”) developed through a partnership between Berkeley Lab and NCAR.  A suite of CESM-1dPOP runs designed to isolate effects of mesoscale air-sea interaction on tropical cyclones and the MJO will be introduced and preliminary results presented.

Presenter(s):
Jim Benedict
Type of event:
Seminar/Symposium
Building:
Mesa Lab
Room:
Main Seminar Room
Will this event be webcast by NCAR/UCAR?
Yes - ML-Main Seminar Room - http://ucarconnect.ucar.edu/live

Posted by Gaylynn Potemkin (Potemkin@ucar.edu) at x1618
Lab/division hosting the event:
NCAR, CGD
Affiliation or organization:
Friday, May 8, 2015 - 12:00pm

Abstract: 

When computational methods or predictive simulations are used to model complex phenomena such as dynamics of physical systems, researchers, analysts and decision makers are not only interested in understanding the data but also interested in understanding the uncertainty present in the data. In such situations, using ensembles is a common approach to accounting for the uncertainty or, in a broader sense, exploring the possible outcomes of a model. Visualization, as an integral component of data analysis task, can significantly facilitate the communication of the characteristics of an ensemble including uncertainty information. Designing visualization schemes suitable for exploration of ensembles is specifically challenging if the quantities of interest are derived feature-sets such as isocontours or streamlines rather than fields of data. 

In this talk, I will introduce novel ensemble visualization paradigms that use a class of nonparametric statistical analysis techniques called data depth to derive robust statistical summaries from an ensemble of feature-sets (from scalar or vector fields). This class of visualization techniques is based on the generalization of conventional univariate boxplots. Generalizing boxplots provides an intuitive yet rigorous approach to studying variability while preserving the main features shared among the members. It also aids in highlighting descriptive information such as the most representative ensemble member (median) and potential outlying members. The nonparametric nature and robustness of data depth analysis and boxplot visualization make such ensemble visualization schemes an advantageous approach to studying uncertainty in various applications ranging from image analysis to fluid simulation to weather and climate modeling.

Presenter(s):
Mahsa Mirzargar
Type of event:
Seminar/Symposium
Building:
Mesa Lab
Room:
Damon Room
Will this event be webcast by NCAR/UCAR?
No

Posted by Carolyn Mueller (cmueller@ucar.edu) at x2491
Lab/division hosting the event:
NCAR, CISL, IMAGe
Affiliation or organization:
Wednesday, May 27, 2015 - 1:30pm

Global 3D density, temperature, and vector magnetic field coronal structure derived from coronal observations

Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal phenomena at all scales. A significant progress has been recently achieved here with deployment of the Coronal Multichannel Polarimeter (CoMP) of the High Altitude Observatory (HAO). The instrument provides polarization measurements of Fe xiii 10747 A forbidden line emission. The observed polarization are the result of a line-of-sight (LOS) integration through a nonuniform temperature, density and magnetic field distribution. In order resolve the LOS problem and utilize this type of data, the vector tomography method has been developed for 3D reconstruction of the coronal magnetic field. The 3D electron density and temperature, needed as additional input, have been reconstructed by tomography method based on STEREO/EUVI data. We will present the 3D coronal magnetic field and associated 3D curl B, density, and temperature resulted from these inversions.

Webcast at https://ucarconnect.ucar.edu/live?room=cg12126

Presenter(s):
Maxim Kramar
Type of event:
Seminar/Symposium
Building:
CG1
Room:
2126
Will this event be webcast by NCAR/UCAR?

Posted by Sheryl Shapiro (sheryls@ucar.edu) at x1567
Lab/division hosting the event:
NCAR, HAO
Affiliation or organization:
Wednesday, May 6, 2015 - 1:30pm

Structure and Dynamics of Quiescent Prominences

Solar prominences are spectacular features. They are highly dynamic, and consist of relatively cool and dense material compared to the surrounding corona. On the solar limb, they appear as huge sheets of plasma, extending up to heights of several hundreds of Mm above the chromosphere. They are referred to as filaments on the solar disk. Prominence plasma is embedded in the dips of helical magnetic fields. High resolution observations are needed for a better understanding of prominence structure and for verifying theoretical models. In this talk, I will present the results of 3D observations (SDO and STEREO views) of three different types of prominences:

  1. We investigate flows in a polar crown prominence observed by SDO on the limb, and find upflows originating from on-disk brightenings seen in STEREO images.
  2. We investigate the triggering mechanism of a giant solar tornado, and suggest that the tornado is the dynamical response of the helical prominence field to expansion of the overlying coronal field (cavity).
  3. We diagnose the dynamics of a prominence/filament cavity system during a series of eight homologous flares. The repeated homologous flares gradually destabilized the prominence/filament system, removed the coronal field above the active region, leading to the CME via the ‘lid removal’ mechanism.
Presenter(s):
Navdeep Panesar
Type of event:
Seminar/Symposium
Building:
CG1
Room:
2126
Will this event be webcast by NCAR/UCAR?

Posted by Sheryl Shapiro (sheryls@ucar.edu) at x1567
Lab/division hosting the event:
NCAR, HAO
Wednesday, June 24, 2015 - 8:00am, Thursday, June 25, 2015 - 8:00am, Friday, June 26, 2015 - 8:00am
NCAR GIS Program BRIGHTE Workshop Series

Extreme weather and climate change impacts vary among different communities and populations, therefore addressing these problems requires spatial thinking and knowledge on integration of climate science and meteorology with Geographic Information Systems (GIS).  Significant progress has been made in the past several years in linking GIS with atmospheric and related sciences and their datasets. There is growing recognition among college and university-level meteorology educators that GIS is an extremely useful tool for atmospheric research and analysis. The intersection of GIS, weather, climate and societal impacts becomes essential when students are learning about interdisciplinary problems that their communities face. However, there is a noticeable lack of not only specific courses that teach the integration of GIS with atmospheric sciences, but perhaps more importantly the resources, such as lab manuals or published exercises, which demonstrate these concepts.

The goal of a 3-day NCAR-sponsored workshop is to provide university/college faculty from meteorology/atmospheric science departments with necessary knowledge to teach introductory GIS concepts and tools in their classrooms. "Incorporating GIS into the Atmospheric Science Curriculum" workshop will consist of hands-on GIS exercises, lectures, discussions, review of published and on-line materials, and working group projects. All data used in the lab exercises will consist of weather, climate, hydrologic, and socio-economic data, making the content not only interesting but very relevant to meteorology/atmospheric science majors. The workshop hands-on training will include: Introduction to GIS Concepts and Methods; Introduction to Esri’s ArcMap and ArcCatalog; Exploring Spatial Data Formats in ArcGIS; Data Symbology and Classification; Cartographic Mapping; Working with Coordinate Systems; and Working with Multidimensional Atmospheric Data.

Climate change adaptation, preparedness for weather extremes, and developing sustainable solutions and practices are important topics for every community in the United States. These complex, interdisciplinary problems require that representatives from all communities are engaged in the sciences and the decision-making process. We invite meteorology/atmospheric science faculty who are interested in incorporating GIS concepts and tools into meteorology, climatology or atmospheric science curriculum. Faculty from U.S. junior colleges, Historically Black Colleges and Universities, Tribal Colleges, and Hispanic-Serving institutions are encouraged to apply.

Application deadline is May 22, 2015. Selected participants will be notified of their acceptance by May 29th, 2015. All selected participants will receive travel support and per diem.

Presenter(s):
NCAR GIS Program
Type of event:
Workshop
Building:
Foothills Labs
Will this event be webcast by NCAR/UCAR?
No

Posted by Lara Ziady (ziady@ucar.edu) at x8442
Lab/division hosting the event:
NCAR, GIS, RAL, CSAP
Affiliation or organization:
Wednesday, June 24, 2015 - 8:00am, Thursday, June 25, 2015 - 8:00am, Friday, June 26, 2015 - 8:00am
NCAR GIS Program BRIGHTE Workshop Series

Extreme weather and climate change impacts vary among different communities and populations, therefore addressing these problems requires spatial thinking and knowledge on integration of climate science and meteorology with Geographic Information Systems (GIS).  Significant progress has been made in the past several years in linking GIS with atmospheric and related sciences and their datasets. There is growing recognition among college and university-level meteorology educators that GIS is an extremely useful tool for atmospheric research and analysis. The intersection of GIS, weather, climate and societal impacts becomes essential when students are learning about interdisciplinary problems that their communities face. However, there is a noticeable lack of not only specific courses that teach the integration of GIS with atmospheric sciences, but perhaps more importantly the resources, such as lab manuals or published exercises, which demonstrate these concepts.

The goal of a 3-day NCAR-sponsored workshop is to provide university/college faculty from meteorology/atmospheric science departments with necessary knowledge to teach introductory GIS concepts and tools in their classrooms. "Incorporating GIS into the Atmospheric Science Curriculum" workshop will consist of hands-on GIS exercises, lectures, discussions, review of published and on-line materials, and working group projects. All data used in the lab exercises will consist of weather, climate, hydrologic, and socio-economic data, making the content not only interesting but very relevant to meteorology/atmospheric science majors. The workshop hands-on training will include: Introduction to GIS Concepts and Methods; Introduction to Esri’s ArcMap and ArcCatalog; Exploring Spatial Data Formats in ArcGIS; Data Symbology and Classification; Cartographic Mapping; Working with Coordinate Systems; and Working with Multidimensional Atmospheric Data.

Climate change adaptation, preparedness for weather extremes, and developing sustainable solutions and practices are important topics for every community in the United States. These complex, interdisciplinary problems require that representatives from all communities are engaged in the sciences and the decision-making process. We invite meteorology/atmospheric science faculty who are interested in incorporating GIS concepts and tools into meteorology, climatology or atmospheric science curriculum. Faculty from U.S. junior colleges, Historically Black Colleges and Universities, Tribal Colleges, and Hispanic-Serving institutions are encouraged to apply.

Application deadline is May 22, 2015. Selected participants will be notified of their acceptance by May 29th, 2015. All selected participants will receive travel support and per diem.

Presenter(s):
NCAR GIS Program
Type of event:
Workshop
Building:
Foothills Labs
Will this event be webcast by NCAR/UCAR?
No

Posted by Lara Ziady (ziady@ucar.edu) at x8442
Lab/division hosting the event:
NCAR, GIS, RAL, CSAP
Affiliation or organization:
Wednesday, June 24, 2015 - 8:00am, Thursday, June 25, 2015 - 8:00am, Friday, June 26, 2015 - 8:00am
NCAR GIS Program BRIGHTE Workshop Series

Extreme weather and climate change impacts vary among different communities and populations, therefore addressing these problems requires spatial thinking and knowledge on integration of climate science and meteorology with Geographic Information Systems (GIS).  Significant progress has been made in the past several years in linking GIS with atmospheric and related sciences and their datasets. There is growing recognition among college and university-level meteorology educators that GIS is an extremely useful tool for atmospheric research and analysis. The intersection of GIS, weather, climate and societal impacts becomes essential when students are learning about interdisciplinary problems that their communities face. However, there is a noticeable lack of not only specific courses that teach the integration of GIS with atmospheric sciences, but perhaps more importantly the resources, such as lab manuals or published exercises, which demonstrate these concepts.

The goal of a 3-day NCAR-sponsored workshop is to provide university/college faculty from meteorology/atmospheric science departments with necessary knowledge to teach introductory GIS concepts and tools in their classrooms. "Incorporating GIS into the Atmospheric Science Curriculum" workshop will consist of hands-on GIS exercises, lectures, discussions, review of published and on-line materials, and working group projects. All data used in the lab exercises will consist of weather, climate, hydrologic, and socio-economic data, making the content not only interesting but very relevant to meteorology/atmospheric science majors. The workshop hands-on training will include: Introduction to GIS Concepts and Methods; Introduction to Esri’s ArcMap and ArcCatalog; Exploring Spatial Data Formats in ArcGIS; Data Symbology and Classification; Cartographic Mapping; Working with Coordinate Systems; and Working with Multidimensional Atmospheric Data.

Climate change adaptation, preparedness for weather extremes, and developing sustainable solutions and practices are important topics for every community in the United States. These complex, interdisciplinary problems require that representatives from all communities are engaged in the sciences and the decision-making process. We invite meteorology/atmospheric science faculty who are interested in incorporating GIS concepts and tools into meteorology, climatology or atmospheric science curriculum. Faculty from U.S. junior colleges, Historically Black Colleges and Universities, Tribal Colleges, and Hispanic-Serving institutions are encouraged to apply.

Application deadline is May 22, 2015. Selected participants will be notified of their acceptance by May 29th, 2015. All selected participants will receive travel support and per diem.

Presenter(s):
NCAR GIS Program
Type of event:
Workshop
Building:
Foothills Labs
Will this event be webcast by NCAR/UCAR?
No

Posted by Lara Ziady (ziady@ucar.edu) at x8442
Lab/division hosting the event:
NCAR, GIS, RAL, CSAP
Affiliation or organization:
Tuesday, May 5, 2015 - 11:00am

Past studies have shown that the feedback of extratropical sea surface temperature on the atmosphere is weak at the interannual time scale. However, some recent evidences suggest that the long-term variability of the North Atlantic SST may exert a significant influence on the Northern Hemisphere atmospheric circulation in winter. Although uncertain due to the shortness of record to examine multidecadal variability, an inverse relationship is found in the 20CR reanalysis between the polarity of the Atlantic Multidecadal Variability (AMV), that depicts the basin-wide fluctuations of the North Atlantic SST with a period of ~70 years, and the decadal trends of the North Atlantic Oscillation (NAO). In order to assess whether the AMV is active in this relationship by forcing the NAO, several perturbation experiments with different configuration of the Community Atmospheric Model version 5 (CAM5) are conducted. Our results suggest that the AMV-SST anomalies have the potential to drive the atmosphere since they induce a significant NAO response in winter, although the response is relatively small compared to atmospheric internal variability. To complete this picture, preliminary results from a multi-model analysis using the Climate Model Intercomparison Project (CMIP5) database are also presented.

Presenter(s):
Yannick Peings
Type of event:
Seminar/Symposium
Building:
Mesa Lab
Room:
Main Seminar Room
Will this event be webcast by NCAR/UCAR?
Yes - ML-Main Seminar Room - http://ucarconnect.ucar.edu/live

Posted by Gaylynn Potemkin (potemkin@ucar.edu) at x1618
Lab/division hosting the event:
NCAR, CGD
Affiliation or organization:
Monday, July 13, 2015 - 8:00am

July 13-16, 2015 | NCAR Foothills Laboratory, Boulder, Colorado

The 2015 NCAR/CDC Workshop on Climate and Health will focus on vector-borne diseases related to human health. This workshop will focus on a wide variety of vector-borne diseases, including dengue, Lyme, and plague, and their relationship to climate variability and change. The purpose of the workshop is to train health professionals and early career climate and health researchers (public health officials, graduate students, post-docs and early career scientists and faculty) in the development of robust interdisciplinary research projects in the complex area of climate and health. The four-day workshop will include lectures on relevant topics in climate and climate change and in public health and human health, vulnerability studies, modeling climate and health, and special tools for analysis (e.g., GIS). There will be multiple opportunities for discussions with experts in the field in order to bring public health practitioners and climate scientists together to examine the integration of epidemiology, ecology, behavioral science, modeling and atmospheric science.

Applications Open through April 30.

Participants will be notified in early May.

Sponsored By:

National Center for Atmospheric Research
Centers for Disease Control and Prevention

Presenter(s):
CDC and NCAR
Type of event:
Workshop
Building:
Foothills Labs
Will this event be webcast by NCAR/UCAR?
No

Posted by Lara Ziady (ziady@ucar.edu) at x8442
Lab/division hosting the event:
NCAR, RAL, CSAP
Affiliation or organization:
Wednesday, May 6, 2015 - 2:00pm

Date:       May 6, 2015
Time:       2pm
Place:       FL 2, Room 1001
Speaker:   Paul Roebber, Atmospheric Science Group and School of Freshwater Sciences
                University of Wisconsin at Milwaukee, Milwaukee, WI 53211
                roebber@uwm.edu

Probabilistic and Deterministic Forecasting using Evolutionary Program Ensembles

Charles Darwin wrote: “Can it … be thought improbable … that other variations useful in some way to each being in the great and complex battle of life, should sometimes occur in the course of thousands of generations? If such do occur, can we doubt … that individuals having any advantage, however slight … would have the best chance of surviving and of procreating their kind?” This is the conceptual basis of evolutionary programming (EP), a process in which simulated evolution is used to find solutions to problems as diverse as the sorting of numbers and forecasting minimum temperature. Despite a history in computer sciences dating back to the 1960s, the application of this idea to meteorological studies is relatively new. Recently, EP has been adapted to the weather domain in order to generate large member ensemble forecasts for minimum temperature, maximum temperature, wind power, and heavy rainfall (Roebber 2013; Roebber 2015abc). These studies have shown that the method can provide greater probabilistic and deterministic skill, particularly at the extremes, than post-processed numerical weather prediction (NWP) ensembles. Further research has shown that this skill advantage persists out to longer ranges, where the forecast signal is presumably weaker.

The method can be understood as follows. Suppose that we have a well-defined problem with a clear measure of success (e.g., root-mean-square-error), and for which we can construct solutions by performing various mathematical operations on a set of inputs. In this case, it is possible to develop a single computer program that generates algorithms which solve the defined problem by applying various operators and coefficients to the inputs. The level of success or "fitness" of a particular solution can then be measured. The idea of fitness invokes evolutionary principles and suggests that if one starts from a very large set of random initial algorithms and allows fit algorithms to propagate some portion of their components to the next generation, then it may be possible to produce improved algorithms over time. This culling of the population in favor of stronger individuals through maximizing fitness and the exchange of "genetic material" between fit algorithms drives the progress towards improved solutions. Since weather forecast problems are nonlinear with non-unique solutions, evolved programs are a new means for generating a set of skillful but independent solutions. The algorithms resemble multiple linear or nonlinear regression equations, but with conditionals that allow for special circumstances to be accounted for as a routine outcome of the data search (e.g., the impact of snow cover on temperature under conditions of clear skies and light winds; Roebber 2010).

In this talk, I will discuss the EP concept and its most recent meteorological forms, including examples from various applications of the method. Roebber (2015abc) modified the technique to incorporate various forms of genetic exchange, disease, mutation, and the training of solutions within ecological niches, and to produce an adaptive form that can account for changing local conditions (such as changing flow regimes) as well as improved forecast inputs – thus, once initial training is completed, the ensemble will adapt automatically as forecasts are produced. I will outline efforts to mitigate the tendency for EP ensembles to exhibit under dispersion as with NWP ensembles and the concept of balancing the minimization of root-mean-square error with the maximization of ensemble diversity. I will then conclude with a discussion of outstanding questions regarding the method and future research directions.

This seminar will be webcasted.

 UCAR Connect Link

http://ucarconnect.ucar.edu/live

Presenter(s):
Paul Roebber
Type of event:
Seminar/Symposium
Building:
FL2
Room:
1001
Will this event be webcast by NCAR/UCAR?

Posted by Marybeth Zarlingo (zarlingo@ucar.edu) at x2751
Lab/division hosting the event:
NCAR, RAL - JNT/DTC
Affiliation or organization:
Wednesday, May 6, 2015 - 12:00pm

Wednesday, 6 May 2015, 12:00 -1:00 pm, ML245 Chapman Room, Mesa Lab, 1850 Table Mesa Drive, Boulder, CO

Modeling future high-resolution dynamic sea level changes

Henk Dijkstra, Utrecht University

Abstract:

Different studies have shown that resolving ocean eddies and boundary currents are of major importance when simulating changes in dynamic sea level on regional scales. In this study, we use the strongly eddying global  (GPU accelerated and multi-platform distributed) version of the Parallel Ocean Program to simulate high-resolution future (up to the year 2100) sea surface height variations (SSH) under the SRES-A1B  forcing scenario. The warming ocean leads to a strong reduction of the Atlantic Meridional Overturning Circulation. At several regions in the Atlantic, shifted eddy pathways cause changes in SSH variability, which have important consequences for regional sea level extremes.

See https://www.esciencecenter.nl/project/esalsa

   

Presenter(s):
Henk Dijkstra
Type of event:
Seminar/Symposium
Building:
Mesa Lab
Room:
ML245, Chapman Room
Will this event be webcast by NCAR/UCAR?
No

Posted by Teresa Foster (teresaf@ucar.edu) at x1741
Lab/division hosting the event:
NCAR, CGD
Affiliation or organization:
Thursday, May 14, 2015 - 3:30pm

Mel Nicholls
University of Colorado, Department of Atmospheric and Oceanic Sciences
Cooperative Institute for Research in Environmental Sciences
Boulder, Colorado

In this seminar a brief summary will be given of recent developments in tropical cyclogenesis research, predominantly from a numerical modeling perspective. This will be followed by a more detailed description of my own specific work in this area that includes investigation of: (1) two distinct pathways to tropical cyclogenesis found to occur in idealized simulations with a non-sheared environment, (2) the mechanisms leading to the formation of a strong mid-level vortex, (3) the development of positive vertical vorticity around the edges of surface cold pools when there is a large scale cyclonic flow present and the role this phenomenon may sometimes play in the formation of vortical hot towers, and (4) how radiation may cause accelerated rates of tropical cyclogenesis and diurnal cycles of convective activity.

This seminar will be webcast live at:
http://www.fin.ucar.edu/it/mms/fl-live.htm

Recorded seminar link can be viewed here:
https://www.mmm.ucar.edu/events/seminars

Thursday, 14 May 2015, 3:30 PM
Refreshments 3:15 PM
NCAR-Foothills Laboratory
3450 Mitchell Lane
Bldg 2 Main Auditorium, Room 1022

Presenter(s):
Mel Nicholls
Type of event:
Seminar/Symposium
Building:
FL2
Room:
1022
Will this event be webcast by NCAR/UCAR?

Posted by Michelle Menard (menard@ucar.edu) at x8189
Lab/division hosting the event:
NCAR, MMM
Affiliation or organization:
Tuesday, May 12, 2015 - 11:00am

IGBP recently asked Will Steffen, the former IGBP Officer about his take on the meaning of the Anthropocene: “The Anthropocene is many things – a term, a concept, a narrative and a paradigm, depending on what area of research one comes from, or what area of interest one brings to bear on it. It is profoundly important, well beyond the research community, because it challenges perspectives and world views on the relationship between humans and the rest of nature.” Our past decisions, as a species, have helped define the Anthropocene and its environment. At first we were, by and large, unaware of the global cumulative impact of our decisions. We are now self aware of the general patterns of our human footprint — perhaps not in all aspects, as we continue to discover linkages, teleconnections, tipping points and thresholds. We continue to monitor and report on our collective earth-surface alterations, while we consider how to lessen our environmental degradation beyond today’s piecemeal approach and generate a more sustainable future. To many researchers, it would come as a surprise if humans were capable of altering the global hydrological cycle. After all, the earth is a water world, and the land surface is relatively small compared to our world oceans. Yet we have already substantively changed surface runoff both quantitatively and qualitatively. Much less water gets delivered to the oceans than just a few decades ago, and the remaining delivery is often delayed from weeks to months, with major consequences to coastal ocean properties and world ecosystems. We have built one large (15+ m high) dam every day, on average, for the last 130 years. Many of our rivers have become confined sluices, engineered with hardened riverbanks, barrages, and tall levees that often lead to a super-elevated river system above historical floodplains. Forensic analysis of recent high cost flood events suggests that infrastructure failures play an increasingly important role (e.g. 2008 Kosi R, India; 2010 Indus, Pakistan; 2011 Chao Phraya, Thailand).  State of the art observational systems allow us to examine “flood” events with unprecedented views — from optical orbital sensors, microwave radiometers, synthetic aperture radars, gravity measurements, time-lapse imagery, DGPS, human intelligence and numerical modeling. The presentation will provide a light romp across the earth using emotion-generating movies and images, as an impetus for the CGD audience to perhaps consider how our species might move forward with a lighter footprint and towards a more sustainable future.

Presenter(s):
James Syvitski
Type of event:
Seminar/Symposium
Building:
Mesa Lab
Room:
Main Seminar Room
Will this event be webcast by NCAR/UCAR?
Yes - ML-Main Seminar Room - http://ucarconnect.ucar.edu/live

Posted by Gaylynn Potemkin (potemkin@ucar.edu) at x1618
Lab/division hosting the event:
NCAR, CGD
Wednesday, May 13, 2015 - 3:30pm

This presentation introduces the characteristics, sources, dynamics and impacts of the gravity waves generated in the moist baroclinic jet-front systems. Firstly, a series of high-resolution cloud-permitting simulations of idealized moist baroclinic waves are performed to study  gravity waves among moist baroclinicjet-front systems with varying degree of convective instability, to examine the similarities and differences of wave characteristics, initiations and propagations among different simulations, and to understand the coupling and interactions of gravity waves with small-scale moist convection and large-scale background baroclinic waves. Secondly, four-dimensional linear ray-tracing experiments are employed to investigate the source mechanisms, propagating characteristics, life cycles, and wavenumber vector refraction budget analysis of the identified lower-stratospheric gravity waves. Thirdly, spectral characteristics are estimated with discrete Fourier transform to assess the wave-induced momentum fluxes and their impacts on the large-scale circulation. Understanding the dynamics,  propagations and impacts of these gravity waves may ultimately help us with better parameterizations of gravity waves associated with moist baroclinic jet-front systems. 

Presenter(s):
Junhong Wei
Type of event:
Seminar/Symposium
Building:
FL2
Room:
1022
Will this event be webcast by NCAR/UCAR?

Posted by Dianne Hodshon (dhodshon@ucar.edu) at x1401
Lab/division hosting the event:
NCAR, ACOM
Affiliation or organization:
Thursday, May 14, 2015 - 12:00pm
Planning, executing and dealing with change is not easy. When organizations or individuals experience unexpected changes, employees are faced with many uncertainties. As a result people often become confused, hurt, stressed and unproductive because coping mechanisms may not be working. Learn how to embrace change by using tools every day to become more calm, productive and less stressed. Upon completion of this session, participants will be able to use techniques and tools to get through the difficult times, and help to regain enthusiasm and energy.

Register at: EOD Training Catalog - https://www.fin.ucar.edu/hrisConnect/employee
(UCAS login>Training Catalog>Search by class>Details>Enroll)
Ensure popups are allowed for the site in your browser.

This session is designed for all employees involved in a changing work environment.

Bring own refreshments

Presenter(s):
Denny Kercher, DO Kercher Enterprises
Type of event:
Seminar/Symposium
Building:
FL2
Room:
Main Auditorium
Will this event be webcast by NCAR/UCAR?
No

Posted by Cheryl Cristanelli (cherylc@ucar.edu) at x8708
Lab/division hosting the event:
UCAR, F&A
Affiliation or organization: