Staff Notes Daily Calendar Events

Monday, November 27, 2017 - 4:30pm

ACOM SEMINAR

Title: What happens to air pollution when it is cold and dark? Insights from the Wintertime INvestigation of Transport, Emissions, and Reactivity (WINTER) Campaign

Presenter: Joel Thornton, Professor of Atmospheric Sciences -University of Washington

Abstract: Emissions of primary pollutants occur year round. Episodes of significantly degraded air quality can occur during wintertime in mid-latitude urban areas. Yet, the rates and mechanisms by which primary pollutants are transformed under the darker and colder conditions of winter remain poorly understood. I will present on forthcoming results obtained from the Wintertime INvestigation of Transport, Emissions, and Reactivity (WINTER) Campaign, which utilized the NSF/NCAR C-130 aircraft to study trace gas and particulate emissions and chemistry across the eastern U.S. during February - March 2015. These observations suggest significant photochemical oxidation occurs, driven by radical precursors not commonly incorporated in chemical transport models, that are strongly linked to local and regional anthropogenic emissions of nitrogen oxides and short-lived VOC. We find that by reconciling model representations of multiphase reactive nitrogen chemistry, related radical precursors and formaldehyde emission sources are consistent with observations.  This allows for an accurate description of secondary nitrate and sulfate aerosol formation and reactive nitrogen partitioning and deposition, which in turn allows for more robust predictions of responses to future changes in emissions.

Joel Thornton is a Professor of Atmospheric Sciences at the University of Washington.   He received his PhD from the University of California Berkeley in 2002 and was than a postdoctoral fellow at the University of Toronto from 2002 – 2004,   His research focuses on understanding the atmospheric chemistry of reactive nitrogen and organic compounds, with an emphasis on aerosol formation and multiphase chemistry.   His group uses a combination of  mass spectrometry, method and instrumentation development, laboratory process studies, in situ observations, and modeling.

Monday, November 27, 2017
Refreshments 3:15pm, Seminar 3:30pm 

NCAR Foothills Laboratory
FL2-1022, Large Auditorium
Live webcast: http://ucarconnect.ucar.edu/live

Type of event:
Seminar/Symposium
Building:
FL2
Room:
1022

Posted by Bonnie Slagel (bonnie@ucar.edu) at x8318
Hosting lab/division or program:
ACOM
Will this event be webcast?
Tuesday, November 28, 2017 - 11:00am

Title: Interpreting precession driven delta-O-18 variability in the South Asian monsoon region

Speaker: Clay Tabor, NCAR

Tuesday, November 28, 2017 - 11:00 a.m.
Mesa Lab, Main Seminar Room

Abstract:
Speleothem records suggest that there has been significant long-term climate variability in the South Asian Summer Monsoon (SASM) region related to precession in Earth's orbit. These records are difficult to interpret because their oxygen isotopic signals can represent several different climate responses. Here, we use CESM with water isotope tracers to directly simulate the isotopic data captured in the speleothems. From these model simulations, we show that a large portion of the orbital signal found in the speleothem records is due to changes in the amount of water vapor coming from different sources. When India receives relatively less insolation in the summer months, most of the local precipitation sources from the nearby ocean. Conversely, when India receives relatively more insolation in the summer months, a greater portion of the local precipitation sources from farther away. Changes in the amount of local evaporation compared to precipitation also have an important effect on the isotopic signals found in the SASM speleothem records.

Type of event:
Seminar/Symposium
Building:
Mesa Lab
Room:
Main Seminar Room

Posted by Barbara Middlebrook (bmiddleb@ucar.edu) at x1366
Will this event be webcast?
Yes - ML-Main Seminar Room - http://ucarconnect.ucar.edu/live
Wednesday, February 7, 2018 - 2:00pm

Studies of Wave Activity in the Thermosphere-Ionosphere System Using Dynasonde Techniques

Dynasonde approach to ionospheric radio sounding capitalizes on high precision of physical parameters and rich statistics of recognized echoes phase-based methods can provide. As has been recently demonstrated, the Dynasonde profiles of the electron density and of the horizontal gradients, complemented with profiles of the Doppler speed, carry comprehensive quantitative information about Atmospheric Gravity Waves, a ubiquitous feature of the space weather that has become an important objective of atmospheric modeling. Being combined into a time series, and without additional processing, the profiles allow visualization of the time fronts of the Traveling Ionospheric Disturbances (TIDs). They also provide high-resolution input data for calculating the complete set of parameters (both vertical and horizontal) of TID activity in the upper atmosphere between the base of the E layer and the maximum of the F layer. Application of the Lomb-Scargle periodogram technique to the tilt data provides unique insight into the dynamics of spectral composition of the TIDs. A similar technique applied to longer time series allows determining characteristics of thermospheric tides. Single sounding sessions allow observations of ionospheric manifestations of acoustic waves produced by ground-based sources. All the mentioned products of the Dynasonde data analysis require a common, standard ionogram mode of radar operation. Therefore, information about standard parameters of the ionospheric E, F regions, possibility to obtain vector velocities characterizing movement of plasma contours, and quantitative parameters of the km-scale irregularity spectrum are not lost and contribute into comprehensive description of wave activity in the thermosphere-ionosphere system. In this presentation we will touch the following topics:

  • Comparison of TID parameters to the ones predicted by the gravity wave dispersion relation;
  • Typical properties of the spectra of thermospheric wave activity;
  • Ocean as a major source of the thermospheric waves;
  • Dynasonde measurements of the momentum deposition by the gravity waves;
  • Concurrent observations of TIDs at two close locations;
  • Measurements of tidal harmonics at thermospheric altitudes;
  • Some special cases of wave activity (solar terminator, eclipse, etc.).
Type of event:
Seminar/Symposium
Building:
CG1
Room:
2126

Posted by Sheryl SHAPIRO (sheryls@ucar.edu) at x1567
Hosting lab/division or program:
HAO
Will this event be webcast?
Wednesday, November 29, 2017 - 1:30pm

Blending of Ground-based and Space-based Magnetograms: Applications to Solar Wind Modeling and L5 Mission Studies

Solar magnetogram data are the primary inputs to models of solar wind transport in the heliosphere. For example, the WSA/Enlil model commonly used for solar wind and CME transport predictions by operational space weather forecast offices relies on NSO/Global Oscillations Network Group (GONG) solar magnetic field measurements to estimate coronal flux tube expansion factors that determine the boundary conditions for the model. But because all current magnetograms are limited to the Sun-Earth line-of-sight, the full-Sun magnetic field is never accurately determined; so-called “synoptic maps” of the solar sphere are temporal averages from a single viewpoint that are at best rough estimates of the solar magnetic field. This has led to calls for magnetogram measurements off of the Sun-Earth line, for example at the L5 Lagrangian point, in order to increase the data available for synoptic map construction. However current plans for L1 missions do not include magnetogram instrumentation, based on the assertion that L5 data can be combined "accurately enough” with ground-based data to improve synoptic maps. In this seminar we discuss the technical challenges of cross-calibrating and combining magnetogram data from different instruments. We use magnetogram data from GONG and SDO/HMI to demonstrate typical issues in magnetogram cross-calibration and to show that unavoidable errors in polar field measurements lead to errors in the WSA/Enlil solar wind predictions, for example the unexpected High-Speed-Stream events of October 2016. Our results confirm that combining magnetogram data from different instruments, even with the same solar view, is very difficult and that cross-calibration of different instruments, with different spatial and spectral resolutions, over varying flux levels and view angles is impossible. The implication is that an accurate measurement of the true full-Sun magnetic field can only be achieved by identical instruments at multiple locations around the Sun, including out-of-the-ecliptic locations that can view the polar regions. A corollary conclusion is that combining space-based L5 magnetogram data with ground-based data to construct an improved synoptic map is likely not feasible. 

Type of event:
Seminar/Symposium
Building:
CG1
Room:
2126

Posted by Sheryl Shapiro (sheryls@ucar.edu) at x1567
Hosting lab/division or program:
HAO
Will this event be webcast?
Tuesday, January 23, 2018 - 8:30am

A Hurricane WRF Tutorial will be held on January 23-25, 2018 at the NOAA Center for Weather and Climate Prediction (NCWCP) in College Park, MD. This will be a three-day event organized by the Developmental Testbed Center (DTC) and by the NOAA Environmental Modeling Center (EMC). The Hurricane Weather Research and Forecast system (HWRF) is a coupled atmosphere-ocean model suitable for tropical cyclone (TC) research and forecasting in all Northern and Southern Hemisphere ocean basins.

Tutorial participants can expect to hear lectures on all aspects of HWRF, including model physics and dynamics, nesting, initialization, coupling with the ocean, postprocessing, and vortex tracking. Additionally, enrichment lectures on HWRF's multistorm capability, TC verification, HWRF ensemble system, and NCEP's future plans for TC numerical weather prediction will be presented. Practical sessions will give tutorial participants hands-on experience in running HWRF.

Date: January 23-25, 2018 

Location: NOAA Center for Weather and Climate Prediction in College Park, MD

https://dtcenter.org/HurrWRF/users/tutorial/2018/

Type of event:
Tutorial/Training

Posted by Jessa Johnson (jessaj@ucar.edu) at x2751
Hosting lab/division or program:
DTC
Will this event be webcast?
No
Thursday, November 30, 2017 - 3:30pm

Joseph Olson
Global Systems Division
NOAA--Earth System Research Laboratory 

The Rapid Refresh (RAP) and High-Resolution Rapid Refresh (HRRR) are NOAA real-time operational hourly updating forecast systems run at 13- and 3-km grid spacing, respectively. Both systems use the Advanced Research version of the Weather Research and Forecasting (WRF-ARW) as the model component of the forecast system. During the second installment of the Wind Forecast Improvement Project (WFIP 2), the RAP/HRRR have been targeted for the improvement of low-level wind forecasts in the complex terrain within the Columbia River Basin (CRB), which requires much finer grid spacing to resolve important topographic features in/near the CRB. Therefore, this project provides a unique opportunity to test and develop the RAP/HRRR physics suite within a very high-resolution nest (∆x = 750 m) over the northwestern US. Special effort is made to incorporate scale-adaptive flexibility into the RAP/HRRR physics suite, with emphasis on the representation of subgrid-scale boundary layer and orographic drag processes.

Many wind profiling and scanning instruments have been deployed in the CRB in support the WFIP 2 field project, which spanned 01 October 2015 to 31 March 2017. During the project, several forecast error modes were identified, such as: (1) too-shallow cold pools during the cool season, which can mix-out more frequently than observed and (2) the low wind speed bias in thermal trough-induced gap flows during the warm season. Development has been focused on improving these common forecast failure modes with the criteria of achieving at least neutral impacts in all other operational forecast objectives. This presentation will highlight the testing and development of various model components, showing the improvements over original RAP/HRRR physics. Examples of case studies and retrospective periods will be presented to illustrate the improvements.  Ongoing and future challenges in RAP/HRRR physics development will be touched upon.

Refreshments: 3:15 pm

Type of event:
Seminar/Symposium
Building:
FL2
Room:
1022

Posted by Bobbie Weaver (weaver@ucar.edu) at x8946
Hosting lab/division or program:
MMM
Will this event be webcast?
Thursday, December 7, 2017 - 3:30pm

William Skamarock
NCAR/MMM 

One of the unsolved questions in atmospheric dynamics concerns the energetics responsible for the horizontal wavenumber k^(-5/3) scaling observed in the mesoscale portion of the atmospheric kinetic energy (KE) spectrum.  Model spectra qualitatively reproduce the observations-based spectrum in both the synoptic-scale k^(-3) and mesoscale k^(-5/3) regions, and given the limitations of the observations, modeling-based studies have become the primary approach for examining the mesoscale dynamics of the spectrum.  We are computing atmospheric spectra for global NWP forecasts using the atmospheric component of the Model for Prediction Across Scales (MPAS) to study these dynamics.  As in past studies, we find a mesoscale region in the model spectrum when resolution is sufficiently fine.  The first part of the present study examines the accuracy of model solutions, where we find that typical model configurations produce solutions that are significantly under-resolved vertically as revealed in convergence test results for KE spectra and examination of inertia gravity wave structure.  The second part of this study examines KE dissipation and its associated dynamics.  The mesoscale region is thought to be characterized as possessing a net downscale energy cascade, and the dynamics in the regions of energy dissipation should play a role in the downscale cascade.   Understanding these dynamics should help test existing theories for the mesoscale KE spectrum.  We will present results illustrating these points,  and we will discuss the implications of these results for current theories for the mesoscale KE spectrum.  We will also discuss the implications for atmospheric modeling applications in weather and climate given that current operational weather and climate model configurations do not resolve well the mesoscale KE, particularly in the upper troposphere and lower stratosphere.

Refreshments: 3:15 pm

Type of event:
Seminar/Symposium
Building:
Foothills Labs
Room:
1022

Posted by Bobbie Weaver (weaver@ucar.edu) at x8946
Hosting lab/division or program:
MMM
Will this event be webcast?
Thursday, November 30, 2017 - 2:00pm

This is the second All-Staff Town Hall on 11/30:

Foothills Lab 2, 1022 Large Auditorium, 2:00-3:00 p.m.

There is an earlier Town Hall at the Mesa Lab, Main Seminar Room, 12:30-1:30 p.m.

Building:
FL2
Room:
1022 - Large Auditorium

Posted by Joanna Schmitz (joanna@ucar.edu) at x1653
Hosting lab/division or program:
UCAR President's Office
Thursday, November 30, 2017 - 12:30pm

This is one of two All-Staff Town Halls on 11/30:

Mesa Lab, 12:30-1:30 PM in the Main Seminar Room.

There will be a second Town Hall this afternoon at Foothills Lab 2 at 2:00-3:00 p.m.

Building:
Mesa Lab
Room:
ML-132 Main Seminar Room

Posted by Joanna Schmitz (joanna@ucar.edu) at x1653
Hosting lab/division or program:
UCAR President's Office